KADALADI TALUK, RAMANATHAPURAM DISTRICT, TAMIL NADU

Transcription

1 KADALADI TALUK, RAMANATHAPURAM DISTRICT, TAMIL NADU MAY, 2016 CONSULTING ENGINEERS 191, ANNA SALAI, CHENNAI

2 FEASIBILITY REPORT FOR 5 X 800 MW KADALADI SUPER CRITICAL THERMAL POWER PROJECT AT KADALADI TALUK RAMANATHAPURAM DISTRICT TAMIL NADU I N D E X Section DESCRIPTION PAGE NO 1.0 INTRODUCTION AND EXECUTIVE SUMMARY Introduction TANGEDCO An Overview Executive Summary Project at a Glance NEED FOR THE PROJECT Power Scenario: Introduction Power Scenario in India Power Scenario in Southern Region Power Scenario in Tamil Nadu Justification of the Project BASIC REQUIREMENTS Introduction 31 5x800 MW-KSCTPP-FR-TANGEDCO INDEX

3 3.2 Land Area requirement & Availability Water Requirement Fuel Requirement Power Evacuation Other Infrastructural Requirements SITE FEATURES Introduction Justificaiton & Discussion on Selected Site Feasibility Consideration TECHNICAL FEATURES Introduction Thermodynamic Cycle Main Plant & Equipment Auxiliary System Electrical System & Equipment Control & Instrumentation Plant Layout Civil Engineering Aspects ENVIRONMENTAL ASPECTS Introduction Environmental Pollution from a Thermal Power Plant & Controlling Measures 127 5x800 MW-KSCTPP-FR-TANGEDCO INDEX

4 6.3 Basic Information for Environmental Clearance Ash Management Plan Gypsum Management Plan PROJECT MANAGEMENT Introduction Construction Facilities Organisation Set-up for Plant Construction Safety & Health Hazard Monitoring Security Labour Welfare & Statutory Regulations PROJECT IMPLEMENTATION & ORGANISATION (O&M) Project Implementation 150 Introduction Project Organisation of the owner Project Execution Project Monitoring, Co-ordination & Control Role of Consultant Project Implementation Schedule 8.2 Organisation Structure 160 Philosophy of Plant Design & Operation Organizational Set-up for Plant Operation Training of Personnel 5x800 MW-KSCTPP-FR-TANGEDCO INDEX

5 9.0 PROJECT COST ESTIMATE & FINANCIAL ASPECTS Basis of Estimates Project Cost Estimate Estimate of Cost of Generation Recommendations & Follow-up Actions 172 5x800 MW-KSCTPP-FR-TANGEDCO INDEX

6 Annexure Sea Water Analysis Annexure Estimation of Consumptive Water Requirement Annexure Analysis of Coal Annexure 4.1 Comparison of Alternate Sites Drawing No.15ZO3-004-DWG-M-001 Vicinity Map Drawing No.15ZO3-004-DWG-M-002 Site Location Map Drawing No.15ZO3-004-DWG-M-003 Plot Plan (2 Sheets) Drawing No.15ZO3-004-DWG-M-008 Coal Connectivity Route Map Annexure 5.1 Brief Technical Features of Major Systems & Equipment Drawing No.15ZO3-005-DWG-M-004 Heat Balance Diagram (Typical) Drawing No.15ZO3-005-DWG-M-005 Water Balance Diagram Drawing No.15ZO3-005-DWG-M-006 Flow Diagram Coal Handling System Drawing No.15ZO3-005-DWG-M-007 Flow Diagram Ash Handling System 5x800 MW-KSCTPP-FR-TANGEDCO INDEX

7 Drawing No.15ZO3-005-DWG-E-001 Single Line Diagram Electrical System Annexure 6.1 List of Basic Equipment/ Instruments for Environmental Monitoring & Testing Drawing No.15ZO3-006-DWG-M-009 Waste Water Management Scheme Drawing No. 15ZO3-007-DWG-M-010 Organisation Chart Drawing No. 15ZO3-008-DWG-M-011 Organisation Chart (O&M Team) Drawing No. 15ZO3-008-DWG-M-012 Project Schedule Annexure Annexure (2 sheets) Project Cost Estimate Financial Tables IDC 5x800 MW-KSCTPP-FR-TANGEDCO INDEX

8 INTRODUCTION AND EXECUTIVE SUMMARY 1.1 INTRODUCTION: M/s Tamil Nadu Generation and Distribution Corporation Limited (TANGEDCO) owns and operates a number of thermal power stations in the state of Tamil Nadu now propose to set up a thermal station of 5x800MW capacity in Kadaladi Taluk of Ramanathapuram district. The station would adopt supercritical technology. The proposed 5x800MW station would require about MTPA (Million tons per annum) (at 85% PLF) using 100% Imported coal (Best Coal), MTPA (at 85% PLF) using blended coal (Design Coal) with ratio of 30% Indigenous coal and 70% Imported coal and MTPA (at 85% PLF) using blended coal (Worst Coal) with ratio of 50% Indigenous coal and 50% Imported coal. The Imported Coal will be from Indonesia or any other country and Indigenous coal will be from Talcher, Odisha. Daily coal requirement at MCR is estimated at Metric Ton (considering Design coal) for the plant. The coal will be received at Thoothukudi sea port and from there it will be transported to project site by rail route. Consumptive water would be drawn from the Sea, the coastal line is at aerial distance of around 2.3 km on the Southern side of the proposed project. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

9 Development Consultants Private Limited has been entrusted by M/s Tamil Nadu Generation and Distribution Corporation Limited (TANGEDCO) to prepare Feasibility report and Detailed Project Report for establishing 5x800MW Kadaladi Super critical Thermal Power Project. 1.2 TANGEDCO AN OVERVIEW: On 1 st July 1957, Tamil Nadu Electricity Board came into being and has remained the energy provider and distributor all these years. During the period the Government have extended the electrical network to all the villages and towns throughout the state. After 53 years of journey on 1st of November 2010 it has restructured itself into TNEB Ltd; Tamil Nadu Generation and Distribution Corporation (TANGEDCO) Ltd; and Tamil Nadu Transmission Corporation (TANTRANSCO) Ltd. MISSION OF THE GOVERNMENT: Tamil Nadu Generation and Distribution Corporation limited is making progress in Generation and Distribution sector. It is happy to inform that the electrification of all villages and towns were completed and also electrification of all households are under progress. GENERATION: To satisfy the energy needs of the state, Tamil Nadu Generation and Distribution Corporation Limited has installed generating stations of capacity MW which includes State, Central 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

10 share and Independent power producers. Besides, the state has installations in renewable energy sources like windmill, Biomass and Cogeneration up to MW. Due to the astronomical increase in energy demand in future, the state has proposed new generation projects for the next 5 years. DISTRIBUTION: TANGEDCO has a consumer base of about lakh consumers ( ). 100% rural electrification has been achieved. Per Capita consumption of Tamilnadu is 1196 units ( ). To achieve the goal of electrification of all households, the Government has launched the Rajiv Gandhi Grameen Vidyutikaran Yojana (RGGVY) scheme. Where grid connectivity is not feasible or not cost effective, Decentralised Distributed Generation is permitted. To achieve reliable and quality power supply and minimise the loss of energy, MOP/GOI has launched the Restructured APDRP scheme under 11th five year plan and the same is being implemented by TANGEDCO. RESTRUCTURING OF ERSTWHILE TNEB: In the G.O Ms No 114 dated , Government of Tamil Nadu has accorded approval in-principle for the re-organisation of TNEB by the establishment of a holding company, by the name TNEB Ltd and two subsidiary companies, namely Tamil Nadu Transmission Corporation Ltd (TANTRANSCO) and Tamil Nadu Generation and Distribution Corporation Ltd (TANGEDCO) 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

11 with the stipulation that the aforementioned companies shall be fully owned by Government. 1.3 EXECUTIVE SUMMARY: M/s Tamil Nadu Generation and Distribution Corporation Limited (TANGEDCO), has proposed to establish 5x800MW Coal based Kadaladi Super Critical Thermal Power Project using imported coal from Indonesia. In Section-2 of the report, existing power situation of the country and the state have been discussed to ascertain the marketability of power from the proposed station. In Section-3 of the report, the basic requirement for setting-up a thermal power station namely land, water, fuel, power evacuation, transportation logistics and infra-structure are discussed. In Section-4 of this report, Salient features of the different sites are furnished. The selected Project Site is located in Tharaikkudi, Kannirajapuram and Narippaiyur villages of Kadaladi Taluk, Ramanathapuram District.. In Section-5 of the report, the technical features of the 800 MW set size outlining the design parameters of main plant and equipment are discussed. A reheat steam cycle with regenerative feed heating arrangement operating at supercritical range has been proposed. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

12 The station envisages supply of imported coal from Indonesia or by any other country and Indigenous coal from Talcher, Odisha by ship upto Thoothukudi Port and then by rail to the site. Plant water supply to the plant is planned from the Gulf of Mannar, the coast line is at a distance of around 2.3 km on the Southern side of the project site. Seawater would be directly used for condenser cooling and the fresh/sweet water requirements would be met by installation of a RO desalination plant. Re-circulating cooling water system with natural Draft cooling towers is envisaged for the station. The fly ash generated is proposed to be handled pneumatically in dry mode up to fly ash silos and transported through truck for utilization by end users and in case of exigency ash from the fly ash silos will be conveyed to ash pond in slurry form. Salient technical features of auxiliary systems are furnished in Section-5 of this report. The electric generators would be 3-phase, 50 Hz, hydrogencooled, 3000 rpm machine with static or brushless excitation system and would Generator voltage will be in the range of 27 kv or as per manufacturer s standard at 0.85 power factor (lagging). The electrical system proposed would be equipped with adequately sized equipment and with generous redundancy to ensure uninterrupted operation. In Section-5 of the report, the electrical equipment and systems are discussed. The proposed station envisages the state-of-the-art Digital Distributed Control & Monitoring Information System (DDCMIS), 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

13 which will integrate various closed loop sub-systems, open loop sub-systems, monitoring and information sub-system covering the entire plant. The system will also integrate the various proprietary control packages supplied by the main equipment vendors for harmonious plant operation. In Section-5 of the report, instrumentation & control philosophy of the proposed station is dealt in adequate details. The Plant layout for the proposed station has been developed keeping in view optimum use of land available within the identified land limit, direction of supplies of input, direction of road access, operational ease and initial investment requirement. Details of basic plant features and the relevant layout within the identified plot are furnished in Section-5 of this report. To minimise emission of Suspended Particulate Matter (SPM) along with boiler flue gases Electrostatic Precipitators of adequate size and fields will be provided at the exit of boiler to bring down SPM emission level to less than 30 mg/nm 3. Total 3 (Three) stacks with stack height of 275 m (Two twin flue for four boilers and one single flue high stack for one boiler) is envisaged for the proposed units. Liquid effluents from the plant will be properly treated before re-use and/or disposal. A detailed scheme for the proposed unit has been provided in Section-5. General discussion on the entire environmental aspects has been provided in Section-6. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

14 Implementation of the project is envisaged to be through EPC contract mode of tendering. Therefore, engineering of facilities and basic infrastructure at project site are to be arranged in advance for smooth implementation of the project. The manpower requirement during construction stage has been estimated and this may undergo revision as per project authority and selected contractor s manpower deployment. Details of the construction facilities are discussed in Section-7. In Section-8 of the report, O&M staff requirement for operating and maintaining the plant is narrated. The manpower requirement for O&M is around 2880 persons. The Man per MW ratio works out to 0.72 (as per the Working Group on Power 12 th Plan Manpower projection for XIII plan). This may undergo revision as per project authority. The training requirements of O&M personnel are also discussed under this section. The commercial operation (COD) for different units of the project from the date of Letter of Award to project Proponent (zero date) shall be as below. Commercial operation of Unit # 1 : 42 months Commercial operation of Unit #2 : 45 months Commercial operation of Unit #3 : 48 months Commercial operation of Unit #4 Commercial operation of Unit #5 : 51 months : 54 months 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

15 The Project Execution, Monitoring and Control, Project Schedule have been discussed under Section-8 of the report. Based on available quotes and in-house data for various equipments, the project cost estimate of 5x800MW has been worked out. The total capital outlay will be of Rs.30, Crores (Including interest during construction working capital, working capital margin and other financial charges). The details are furnished in Section-9 of the report. 1.4 PROJECT AT A GLANCE: GENERAL: Project Authority : Tamil Nadu Generation and Distribution Corporation Limited (TANGEDCO). A Government of Tamil Nadu Undertaking. Project : Imported coal based 5x800MW Kadaladi Super Critical Thermal Power Project. Selected Location : The selected site is located in Tharaikkudi, Kannirajapuram and Narippaiyur villages of Kadaladi Taluk, Ramanathapuram District in Tamil Nadu State. The coordinates of the selected site is as below Node Latitude Longitude B N E B N E B N E B N E 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

16 Nearest Major Town/City : Ramanathapuram, which is around 65 kms from the proposed site and Thoothukudi city which is at a distance of 55 Kms. Seismic Zone : Zone II as defined in - IS: Access by Road Access by Rail Access by Sea Access by Air : The site is located on the North side of East Coast Road (ECR) connecting Ramanathapuram and Vembar. : Ramanathapuram Railway Station, at 65 Kms and Thoothukudi Railway Station at 55 Kms from site : Thoothukudi Port - 75 km from site. : Domestic airport at Thoothukudi (55 kms approx.)/international airport at Madurai (120kms approx.). PRELIMINARY PROJECT PARTICULARS: Main Fuel : Imported Coal with GCV 5642 kcal/kg is proposed to be imported from Indonesia or any other country and Indigenous coal with GCV 2800 kcal/kg from Talcher, Odisha. Coal Requirement: Best Coal MTPA (Million tons per annum) at 85% PLF (100% imported coal) metric T/day, 7394 TPD per unit 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

17 Design Coal MTPA at 85% PLF (70% imported: 30% indigenous) metric T/day, 8798 TPD per unit Worst Coal MTPA at 85% PLF (50:50) metric T/day, TPD per unit Fuel Transportation :Imported coal will be transported from the overseas supplier Indonesia or any other country and Indigenous coal from Talcher, Odisha to Thoothukudi Port by ship. For Coal connectivity a combination of existing Rail network, proposed new B.G line project and private railway line to the power plant is proposed. The coal from Thoothukudi port will be transported to site by one of the following rail route. i) Coal will be transported by the existing railway line from Thoothukudi Port to Milavittan, then through the proposed B.G railway line (Kanyakumari to Karaikudi via Ramanathapuram) which aligns along the southern side of the proposed site and then by private railway line take-off from a location nearer to the Power Plant. Or ii) Coal will be transported by the existing railway line from Thoothukudi Port to Milavittan, then through the 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

18 proposed new alignment of B.G railway line (Thoothukudi to Madurai via Melamarudur)to Melamarudur. From Melaamarudur to the power plant private railway line is proposed. : Oil will be transported by road tankers. Water : The estimated seawater requirement for the proposed Thermal Power Plant is 39,193m 3 /hr (41,150 m 3 /hr with 5% margin). Consumptive water would be drawn from the Sea and treated in Desalination plant at site. The sea coastline is at an aerial distance of around 2.3 km on the southern side of the proposed plant. Land : About 1642 acres of land will be required for setting the power station including ash pond, coal stock pile etc. About 522 acres of land is considered for Bottom ash slurry disposal and fly ash slurry disposal. The ash dyke area is considered for the following % disposal of fly ash in slurry form 1 st year 100% fly ash 2 nd year 75% fly ash 3rd year 50% fly ash 4 th year 25% Fly ash 5 th Year 0% fly ash About 670 Acres of land is considered for plant area, lay down area, storage area etc. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

19 About 300 acres of land area will be required for Green belt and 150 acres land will be required for Township (to be indentified outside plant boundry). Site Elevation : +6 m above Mean Sea Level (MSL). TECHNICAL FEATURES OF 5X800 MW UNITS: Power Generating Unit : Five units of 800 MW turbine generator sets fed by steam from coal fired Pulverised Fuel boilers operating at supercritical range. Minimum Steam Condition : 255 bar (a) / 565 C At Steam Turbine Inlet Cooling System Coal Handling System Ash Disposal System : Recirculating type cooling water system with wet type Natural Draft Cooling Towers using sea water as cooling medium. : Imported coal and Indigenous coal will be transported by Railway through BOBRN type wagons to site from Thoothukudi port. Coal storage (considering worst coal) for 30 days approx. and coal mill bunkers storage for 14 hours is proposed. : Dry collection and disposal of Fly Ash, Dry extraction of bottom ash is considered. Ash will be primarily disposed by truck to end users as far as possible. Besides provision will be made to transport fly ash 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

20 (only during emergency) and Bottom ash through pipe line to the ash dump area (located nearby within the Plant boundary). Power Evacuation : Power generated in the Power Plant would be available at 765 kv level in the station switchyard bus. Power from this switchyard would be evacuated through two (2) 765kV double circuit lines to the nearest 765 kv pooling station, location to be decided by TANTRANSCO the local STU. Power Off-take Environmental Aspects : Through TANTRANSCO. : 3Nos. (Three) stacks with stack height of 275 m (Two twin flue stack and one single flue stack) is proposed for the 5x800MW units to meet the MOEF standard required for dispersion of particulate, SO X and NO X. Provision of FGD & SCR is proposed for this project to reduce the SOx & NOx levels (100 mg/nm 3 ) within the prescribed norms as specified in the latest MOEF notification. : ESP Multiple field electrostatic precipitators with separation efficiency of around 99.9% is envisaged for steam generator. The limit for emission of particulate matters is 30 mg/nm 3 : The reject water (brines) from R.O desalination plant will be diluted to specified limits and the cooling 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

21 water blow down temperature will be brought down to specified limit. And then RO Reject along with blow down from cooling tower will be pumped back to sea as per Tamil Nadu Pollution Control Board (TNPCB) standards and the Ministry of Environment & Forest's (MOEF) notification. The other effluents from the plant area will be treated in ETP plant and Waste water generated from ETP will be treated and utilized for horticulture development and excess treated water is sent to ETP RO plant to achieve zero waste water discharged as per MOEF notification. Manpower Requirement : 2880 personnel during plant operation for O&M. The Man per MW ratio works out to 0.72 (as per the Working Group on Power 12 th Plan Manpower projection for XIII plan) OTHER FACILITIES: Township Mode of Implementation Project Time Frame : Residential Quarters for employees employed in critical services will be provided. : The project will be executed on Engineering, Procurement & Construction (EPC) basis in one or multiple packages. : First unit of 800MW capacity Unit would be put into commercial operation in about 42 months from the date of Letter of Award to project Proponent and 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

22 subsequently the other units would be brought into commercial operation in 3 months interval for each unit. COD Unit #1 :42 months COD Unit #2 COD Unit #3 COD Unit #4 COD Unit #5 PROJECT COST & COST OF GENERATION: :45 months :48 months :51 months :54 months Project Cost : Present day cost including Interest During Construction (IDC), financial charges and Working Capital Margin money is Rs.30, Crores. Corporate social responsibility (CSR) : The value considered for the CSR activities is not less than 0.4 % of the project cost. Cost of 85% PLF & 85% PAF is as below:- 1 st year of full generation : Rs.3.42perkWh. (all 5 units are in operation) 25 years levelised tariff : Rs.5.70per kwh. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 1

23 2.1 POWER SCENARIO: INTRODUCTION: NEED FOR THE PROJECT Electricity is the prime mover of growth and is vital to the sustenance of a modern economy. The projected growth of the Indian Economy depends heavily on the performance and growth of the power sector. The contribution of power sector in country s growth has grown significantly since independence. Total installed generation capacity of the country, which was 1362 MW at the time of independence, has increased to about MW as on 31st January, It is the endeavor of the government to ensure uninterrupted supply of electricity at affordable rates to the following categories of consumers to sustain steady economic growth:- a. Domestic b. Commercial c. Public Lighting d. Public Water Works e. Irrigation f. Industrial (LT, HT less than 1 MW, HT 1 MW and above) g. Railway Traction h. Bulk Non-Industrial HT supply Electricity is an essential requirement for all facets of our life. It is the critical infrastructure on which the socio-economic development of the country depends. Availability of reliable and quality power at competitive rates to industry would make it globally competitive and enable it to exploit the tremendous potential of employment generation. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

24 2.2 POWER SCENARIO IN INDIA The power industry in India is historically being characterized by energy shortages i.e. demand for electricity far exceeding the supply. Due to inadequate generation supply and distribution infrastructure, the per capita consumption of energy in India is extremely low in comparison to most of the developing and developed nations. However, as per CEA record, the per capita consumption of electricity in India in the year stands as 918 kwh (SOURCE: Report on Power Scenario by CEA SEP- 2014). Over the years, the electricity Industry has made significant progress. The Present power scenario of India is shown in the following tables TABLE ALL INDIA INSTALLED CAPACITY (as on ) (FIGURES IN MW) Thermal Sector Coal Gas Diesel Total Nuclear HYDRO R.E.S (MNRE) Total STATE PRIVATE CENTRAL TOTAL % SOURCE: CEA 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

25 TABLE ACTUAL POWER SUPPLY POSITION Feasibility Report Period Peak Demand (MW) Peak Met (MW) Peak Deficit / Surplus (MW) Peak Deficit / Surplus (%) Energy Requirement (MU) Million Units Energy Availability (MU) Energy Deficit / Surplus (MU) Energy Deficit / Surplus (%) 9 TH PLAN END TH PLAN END TH PLAN END 130, ,191-13, , ,886-79, , ,294-12, , ,209-86, , ,815-6, ,002, ,829-42, , ,160-7, ,068,923 1,030,785-38, SOURCE: CEA It may be noted from the Table 2.2 there is always energy deficit for all the plan period. The energy deficit in India is mainly caused by slow progress in the capacity addition which in turn is attributable to difficulty in land acquisition, shortage of coal, lack of fund allocation and the clearances involved. The Indian economy is directed by the successive five year plans that set out targets for economic development in various sectors, including power sector. During implementation of the last three (3) Five Year Plans (the 9 th, 10 th and 11 th Plans), 48%, 52% & 70% of the targeted additional energy capacity could only be attained. Capacity addition to the tune of approximately 20,000 MW, 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

26 21,000 MW & MW was achieved in 9 th,10 th & 11 th Plan periods. (Source: CEA POWER SCENARIO STATUS NOTE- SEP 2014). The projection at the end of 13 th plan on Indian Power Scenario is furnished in the following table. TABLE 2.3 PROJECTION FOR THE END OF 13 TH PLAN REGION ENERGY REQUIREMENT (MU) Million Units PEAK DEMAND (Mw) Y e a r Y e a r Northern Western Southern Eastern N-Eastern Andaman & Nicobar Lakshadeep All-India Source : 18 th EPS. The proposed project of 5x800 MW coal based power station at Kadaladi taluk, in Ramanathapuram District, Tamil Nadu fits well in the overall power scenario of the country and plant operation at high plant load factor can be expected. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

27 2.3 POWER SCENARIO IN SOUTHERN REGION: For the purpose of power planning and operation of regional grid the Southern Region consists of the following states/ut/command area: Andhra Pradesh Telangana Karnataka Kerala Tamil Nadu Puducherry All three sectors namely Central, State & Private contribute to the power generation capability in the region. Power Grid Corporation of India Limited (PGCIL), the central sector constructs, operates and maintains transmission and transformation facilities for inter-state and inter-region transfer of power. The power generating capability in the region is predominantly thermal. The total installed capacity in Southern region as on is MW as in indicated in Table 2.4. Energy deficit to the tune of (-) 35,269 MU (Million Units) and peak demand deficit of (-) 8619 MW had been anticipated during the period of in Southern Region refer Table x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

28 TABLE SOUTHERN REGION INSTALLED CAPACITY (as on ) (FIGURES IN MW) Thermal Sector Coal Gas Diesel Total Nuclear HYDRO R.E.S (MNRE) Total STATE PRIVATE CENTRAL TOTAL % SOURCE: CEA TABLE SOUTHERN REGION ANTICIPATED POWER SUPPLY POSITION DURING AS PER LGBR Peak Demand (MW) Peak Available (MW) Peak Deficit / Surplus (MW) Peak Deficit / Surplus (%) Energy Requirement (MU) Energy Availability (MU) Energy Deficit / Surplus (MU) Energy Deficit / surplus (%) 43,630 35,011-8, , ,979-35, SOURCE: LGBR report x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

29 TABLE ACTUAL POWER SUPPLY POSITION Period Peak Demand (MW) Peak Met (MW) Peak Deficit / Surplus (MW) Peak Deficit / Surplus (%) Energy Requirement (MU) Energy Availability (MU) Energy Deficit / Surplus (MU) Energy Deficit / Surplus (%) 9TH PLAN END 10TH PLAN END 11TH PLAN END ,599 32,188-5, , ,480-22, ,767 31,586-7, , ,058-43, ,015 36,048-2, , ,444-18, ,094 37,047-2, , ,136-11, SOURCE: CEA As per 18 th EPS Committee Notes, electrical energy requirement for Southern region would be 506,589 MU by the end of 13 th Plan period (Table 2.3). Average peak electrical load for Southern region forecast is MW by the end 13 th Plan. It is to be noted that as per 18 th EPS Committee survey report (Table 2.3) and the currently installed capacity of the southern region as per Table 2.4, a rapid capacity addition through large scale thermal power development program is required. In this scenario, proposed power station of 4000 MW in Tamil Nadu is assured of steady demand in the region. It is thus possible to run the proposed station at high PLF 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

30 2.4 POWER SCENARIO IN TAMIL NADU Feasibility Report Being located on the South eastern coast of India the total geographical area of Tamil Nadu covers 3.95% of the total geographical area of India and houses 7.21 Crore population as per latest Census. The Per capita consumption of electricity in Tamilnadu during the year was kWh (Source : CEA POWER SCENARIO STATUS NOTE- SEP 2014). The following tables show the present power scenario of Tamil Nadu. TABLE TAMIL NADU INSTALLED CAPACITY (as on ) (FIGURES IN MW) Thermal Sector Coal Gas Diesel Total Nuclear HYDRO R.E.S (MNRE) Total STATE PRIVATE CENTRAL TOTAL % SOURCE: CEA 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

31 TABLE TAMILNADU ANTICIPATED POWER SUPPLY POSITION DURING AS PER LGBR Period Peak Demand (MW) Peak Available (MW) Peak Deficit / Surplus (MW) Peak Deficit / Surplus (%) Energy Requirement (MU) Energy Availability (MU) Energy Deficit / Surplus (MU) Energy Deficit / Surplus (%) ,489 13, ,653 98,123-4, SOURCE: LGBR report TABLE TAMILNADU ACTUAL POWER SUPPLY POSITION FROM IX PLAN Period Peak Demand (MW) Peak Met (MW) Peak Deficit / Surplus (MW) Peak Deficit / Surplus (%) Energy Requirement (MU) Energy Availability (MU) Energy Deficit / Surplus (MU) Energy Deficit / Surplus (%) 9TH PLAN END TH PLAN END 11TH PLAN END ,813 10,566-2, ,685 76,705-8, ,736 11,053-1, ,302 76,161-16, ,522 12,492-1, ,508 87,980-5, ,707 13, ,758 92,750-3, SOURCE: CEA 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

32 TABLE TAMILNADU PEAK & ENERGY FORCAST YEAR ENERGY DEMAND (MU) Million Units SOURCE: 18 th EPS PEAK DEMAND (MW) As per 18 th EPS Committee Notes, energy requirement for Tamil Nadu at the end of 13 th Plan period is estimated/forecast as MU. Peak electric load at the end 13 th Plan is estimated/forecast as MW. It is to be noted that as per 18 th EPS Committee survey report Table 2.10 and the currently installed capacity of the state as per the Table 2.7 a rapid capacity addition through large scale thermal power development program is required. In view of shortage of power in the state and in order to bridge the demand-availability gap of power, Tamil Nadu Generation and Distribution Corporation Limited (TANGEDCO) is exploring the possibility of establishing more thermal power projects. The Government of Tamil Nadu in the budget speech for the year had announced that a 5x800MW Kadaladi Supercritical Thermal Power Project will be established in Ramanathapuram District. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

33 2.5 JUSTIFICATION OF THE PROJECT: Feasibility Report With the present and future mismatch between demand and supply for Indian power scenario, any capacity addition will be an welcome relief to attain the growth figures projected in Electricity Power Survey (EPS) as well as to maintain a steady growth in Gross Domestic Product (GDP). The diesel or gas turbine plant plays a vital role in the power industry as the response of these plants to the fluctuating power is very high and they can be built anywhere. The use of these plants in India for power generation is limited due to limited sources of oil and gas in the country which are essential and required for industrial and transport purposes. The hydel power stations are subject to the vagaries of weather and the availability of water and hence assured power supply from the same cannot be guaranteed throughout the year. Therefore, total reliance on hydel stations is not advisable. The nuclear power plants needs stringent safety precautions and need more sophisticated safeguards to protect the personnel and environment. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

34 Wind contains tremendous amount of energy, it can be harnessed to generate power on a large scale matching with conventional sources. The total installed wind capacity in India is (31st March, 2015) of which Tamil Nadu with installed capacity of MW accounts for %. India is ranked number one in terms of solar energy production per watt installed. Total installed capacity as on 15 th Jan, 2016 is 5,130 MW of which Tamil Nadu with installed capacity of 419 MW accounts for 8.16 %. Land is a scarce resource in India and per capita land availability is low. Dedication of land area for exclusive installation of solar arrays might have to compete with other necessities that require land. The amount of land required for utility-scale solar power plants currently approximately 1 km 2 for every megawatts (MW) generated could pose a strain on India's available land resource. Installation of wind power plant depends on availability of wind with required wind speed. Very few locations satisfying above criteria are identified in Tamil Nadu. Further wind based power plants are operating at very low PLF of 25-30%, hence dependence on wind based power plant as base load plant is not feasible. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

35 In such a situation, it is prudent to implement base load power plants using coal as fuel and thermal power generation as the best preferred alternative. The actual growth in industrial, agricultural and domestic demand will establish that there is an appreciable shortfall in the installed capacity and energy availability as on date. Electricity consumption in Tamil Nadu is increasing at a rate faster than over all energy supply. Considering the projected demand at end of 13th year Plan as per 18th Electricity power survey report Table 2.10 and the currently installed capacity of the state a per the Table 2.7, a rapid capacity addition through large scale thermal power development program is planned during 13th year Plan ( ). Pulverized Fuel Firing combustion is the most common and well proven among all the above technologies. PF fired boilers are most suited for higher capacity power plants and have the distinct advantage of better combustion efficiency with less auxiliary consumption as compared to any other technology in the market today. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

36 The choice of unit capacity for the coal fired station depends largely upon considerations of efficiency and adherence to environmental norms. Increase in steam parameters namely pressure and temperature lead to increase in efficiency, which in turn, reduces emission of greenhouse gases. Increase in steam pressure beyond 221 bar leads to supercritical conditions in the thermodynamic steam water cycle and results in sizeable efficiency improvement. While supercritical steam parameters have been more effective in capacity range of 600 MW and above. Any unit size from 660 MW to 800 MW of gross capacity at generator terminal having supercritical technology for the proposed plant can be considered. However, keeping in view the higher efficiency, improve heat rate, low per MW cost, Lower emission of CO 2, SO x & SPM and in current scenario unit capacity of 800MW Supercritical technology is being widely adopted throughout India and henceforth the selection of 800MW unit capacity is justified for this proposed project. This shortfall will continue even after the commissioning of the proposed power plants in various parts of the state and in the southern regions. As Tamil Nadu state is the most preferred state for industrialization, the industrial demand for power will 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

37 be ever increasing. Adding to the industrial demand the agriculture need as well as domestic consumption coupled with the improved standard of living of the population will be on the rise. The location being close to the sea, cooling water is perennially available in the site for the power plant. Imported coal is being considered as the main fuel for the proposed power plant. Further the grid is large enough to accommodate this proposed 5x800MW coal fired power plant. Besides Kadaladi Taluk in Ramanathapuram District is a very backward area and prone to communal disturbances, a power plant of this 5X800 MW capacity will bring in lot of employment opportunities both direct and indirect and will pave away for communal harmony in this area. Taking all these into consideration, establishment of the proposed power project of 5x800 MW is justified in all aspects. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 2

38 3.1 INTRODUCTION: BASIC REQUIREMENTS The basic requirements for setting up and operating a 5x800MW coal based thermal power station are - Availability of adequate land suitable for setting up the station Availability of adequate quantity of water throughout the year Guaranteed supply of fuel with effective transportation system to ensure optimum cost of fuel at the plant Power evacuation possibility to the identified sub-station(s) of the grid at appropriate voltage level(s). Accessibility to the site for start of construction, availability of construction water and power, availability of construction manpower, road connection to airport, seaport, etc. Connectivity to population centres with social and civic amenities This section discusses the requirements vis-à-vis the availability above basic elements of setting up the proposed power station. TANGEDCO had identified few potential sites and the proposed site has been considered for setting up of the Project after review and consideration of above stated aspects. 5x800 MW-KSCTPP-FR-TANGEDCO -31- SEC - 3

39 3.2 LAND - REQUIREMENT & AVAILABILITY: Feasibility Report The land requirement for a coal based thermal power project can broadly be classified under the following five major heads: - a. Main Plant Area b. Area required for Roads, Railway siding, Coal stack yard, pipe corridors, cooling tower, switch yard, Administrative Building, etc. c. Ash Disposal Area d. Other land area requirements for infrastructure facilities such as land for sea water intake & outfall piping corridor, power evacuation corridor, environmental requirements, lay down area etc. e. Green belt Depending on the site features, land configuration and related technical requirements, the tentative break-up of land requirements for a typical 5x800MW imported coal fired power plant with provisions of development of relevant infrastructure and support facilities, may be considered as follows:- 5x800 MW-KSCTPP-FR-TANGEDCO -32- SEC - 3

40 LAND REQUIREMENT AREA IN ACRES MAIN PLANT AREA BTG FOR FIVE (5) UNITS 56 ELECTRICAL AREA (TRANSFORMER YARD,SWITCHYARD & CONTROL ROOM) 102 COAL HANDLING PLANT INCLUDING MGR & FUEL OIL AREA 149 ASH HANDLING PLANT, FGD & MILL REJECT SYSTEM 71 PLANT WATER SYSTEM, WASTE WATER SYSTEM AND CW CORRIDOR 144 AUXILLARY BUILDINGS, PLANT FACILITIES AND ROADS 148 ASH POND AREA 522 GREEN BELT 300 TOWNSHIP 150 Total Land Requirement, Acres 1642 PLANT AREA: The above land requirement envisaged for the power plant considers installation of 5x800 MW capacity imported coal based thermal power station with relevant facilities. The estimated space requirement considers a sea water storage, cooling towers, coal receipt by rail route, coal storage and handling facility, fuel oil system, 765 kv GIS switchyard, sea water treatment facilities, desalination plant to meet consumptive water requirement, Flue gas desulphurisation plant, green belt to satisfy State PCB/MOEF norms, etc. 5x800 MW-KSCTPP-FR-TANGEDCO -33- SEC - 3

41 ASH DISPOSAL AREA: About 4.05 MTPA of ash (considering Worst coal 50% imported: 50% indigenous & at 85% PLF) is likely to be generated in a year from the proposed power station. An average ash dump height of 15M is envisaged for estimation of land requirement for ash dump yard/ash pond. Actual height will, however, depend on ground condition of dump and its contour. The ash disposal area is decided considering Bottom ash slurry disposal for 25 years and fly ash disposal in slurry form in the 1 st year- 100%, 2 nd year-75%, 3 rd year-50% and 4 th year-25%. This area includes the peripheral road and statutory green belt around the disposal area. As per the Ministry of Environment & Forests notification dated 3 rd November, 2009, 100% fly ash utilisation from the complex need to be ensured within initial four years of operation. Thus the land requirement works out to about 522 Acres for fly ash disposal for initial years and 25 years for bottom ash. It would consider disposal with a dump height of 15m. OTHER AREA: The site for the proposed power plant is planned on a plot of land with no habitation. The site was identified on the basis of following criteria:- Availability of adequate land for locating the power plant with minimum resettlement and rehabilitation issues. Land is predominantly flat. However, certain amount of land filling and cutting would be necessary. 5x800 MW-KSCTPP-FR-TANGEDCO -34- SEC - 3

42 Assured availability of sea water from the Gulf of Mannar located within 2.3 km. The proposed site is on the Northern side of East Coast Road (ECR) connecting Ramanathapuram and Vembar. Imported coal will be transported from the overseas supplier (Indonesia or any other country) and indigenous coal from Odisha by sea to Thoothukudi Port and then by the rail Thoothukudi Port. Hence the Site is well connected by road/sea/rail for transportation of fuel, construction material, equipment etc., will not be a problem. Power generated in the Power Plant would be available at 765 kv level in the station switchyard bus. Power from this switchyard would be evacuated through two (2) 765 kv double circuit lines to the nearest 765 kv pooling station, location to be decided by TANTRANSCO the local STU. The vicinity map of the area identified is given in Drawing No.15Z DWG-M-001. The site location map of area is given in Drawing No.15Z DWG-M-002. It may be seen that the land available is suitable for locating the proposed power plant with all the auxiliaries and accessories. In the subsequent section, details of the identified site are discussed in adequate details. The estimated space requirement considers closed circulating cooling water system with cooling towers, Rail way line, Coal storage and handling facility, fuel oil system, 765 kv switchyard, desalination plant to meet consumptive water requirement, Flue gas desulphurisation (FGD) plant, green belt to satisfy TNPCB/MOEF norms, etc.. 5x800 MW-KSCTPP-FR-TANGEDCO -35- SEC - 3

43 Township: Residential accommodation with necessary civic amenities would be provided for the O &M personnel of the proposed station in a separate plot of land outside plant boundary to be located nearer to the project area. The area would include civic amenities required for such township located at a remote location. The plot needs to be adequate for provision of green verge. Total area to be identified outside plant boundary for township is 150 acres. Water Corridor Seawater would be directly used for condenser cooling and the fresh water requirements would be met by installation of a desalination plant. The sea coastal line is at aerial distance of around 2.3 km on the Southern side of the proposed project. The intake well along with intake pump house to be located offshore in Gulf of Mannar. Two intake sea water pipes from the intake pump house in off shore to the plant site is planned to cater to the water requirement for the station and two outfall line. Considering the submergence requirement for the pumps, Intake Pump House to be located at a depth of about 5 m (tentative) will be suitable. The Intake structure shall be suitably designed with necessary Trash Racks and Stop Logs. This arrangement minimizes occurrence of silt carry over to the Plant.The outfall to be located around 1.5 km (approx.) into the sea away from the intake point. Intake and Outfall pipelines are proposed to be laid over pile supported RCC deck. A common RCC deck (15 m width) will be provided for both intake and outfall pipes for about 4 km (tentative) and separate RCC deck shall be laid beyond this point 5x800 MW-KSCTPP-FR-TANGEDCO -36- SEC - 3

44 for outfall about 1.5 km (tentative). For laying water pipeline of route length of about 2.3 km and the pipeline corridor of width 20 m from sea shore to plant boundary, the land shall be identified. The tentative location is indicated in the Drawing No.15Z DWG-M-003 (sheet 2 of 2). However, the location of the intake and outfall is to be finalised based on the Marine EIA/EMP study & the intake and outfall Modelling study. 3.3 Water Requirement: In a conventional fossil fuel-fired thermal power station, water is used to meet the following consumptive requirements. a. Cooling water for steam condenser to act as the heat sink for the thermodynamic cycle. However, for power stations employing semi-open recirculating cooling systems with cooling towers, only a small percentage of total circulating water flow is required as make-up. The cooling water system in a large sized thermal power plant is the largest consumer of water and its make-up requirement itself accounts for more than 70% of the total consumptive water requirement of the power station. b. Cooling of electrical and mechanical auxiliary equipment, such as, generators, transformers, large motors, compressors and other heat exchangers shall be through closed circuit auxiliary cooling system using demineralised water as the primary 5x800 MW-KSCTPP-FR-TANGEDCO -37- SEC - 3

45 coolant and main circulating cooling water as the secondary coolant. c. Make-up water requirement for power cycle (boiler makeup). d. Water for miscellaneous services such as:- i) Fire fighting system ii) General services viz. airconditioning, ventilation, service water, dust suppression, dust extraction, FGD etc. iii) Potable water for plant and township. Water required for the station would be drawn from Gulf of mannar. The estimated consumptive water requirement based on sea water analysis shown in Annexure-3.1 for the 5x800 MW capacity station is at m 3 /hr (7839 m 3 /hr per unit) (~385 cusecs). The break-up of the estimate is given in Annexure The estimates are based on adoption of cycle of concentration (COC) in the circulating cooling water circuit as Fuel Requirement: The proposed site is on the Northern side of East Coast Road (ECR) connecting Ramanathapuram and Vembar. Imported coal will be transported from the overseas supplier (Indonesia or any other country) or indigenous coal from Odisha will be transported to Thoothukudi Port by ship. 5x800 MW-KSCTPP-FR-TANGEDCO -38- SEC - 3

46 For Coal connectivity a combination of existing Rail network, proposed new B.G line project and private railway line to the power plant is proposed.the coal from Thoothukudi port will be transported to site by one of the following rail route. i. OPTION I - Utilizing the proposed new alignment of B.G railway line from Kanyakumari to Karaikudi via Ramanathapuram. (Status of the new alignment - decision is awaited from Railway Board) Coal will be transported by the existing railway line from Thoothukudi Port to Milavittan, then through the proposed B.G railway line which aligns along the southern side of the proposed site and then by private railway line take-off from a location nearer to the Power Plant. Or ii. OPTION II - Utilizing the proposed new alignment of B.G railway line from Thoothukudi to Madurai via Melamarudur. (Status of the new alignment - sanctioned by Railway Board) Coal will be transported by the existing railway line from Thoothukudi Port to Milavittan, then through the proposed new alignment of B.G railway line to Melamarudur. From Melamarudur to the power plant private railway line is proposed. The coal analysis for imported coal & Indigenous Coal is given in Annexure x800 MW-KSCTPP-FR-TANGEDCO -39- SEC - 3

47 On the basis of Best coal (Imported Coal 100%) the estimated coal requirement would be as below : Fuel Particulars 5 x 800 MW Per unit TG Heat Rate 1850 kcal/kwh - Boiler Efficiency 89% - Station Heat MCR with margin 2173 kcal/kwh - Hourly coal requirement at MCR 1541TPH 308 TPH Daily coal MCR 36974TPD 7394 TPD Annual Coal 85% PLF MTPA 2.3 MTPA On the basis of Design coal (Imported Coal 70% : Indigenous coal 30%) the estimated coal requirement would be as below: Fuel Particulars 5 x 800 MW Per unit TG Heat Rate 1850 kcal/kwh - Boiler Efficiency 88.1% - Station Heat MCR with margin 2195 kcal/kwh - Hourly coal requirement at MCR 1833 TPH 367 TPH Daily coal MCR TPD 8798 TPD Annual Coal 85% PLF MTPA 2.73 MTPA On the basis of Worst coal (Imported Coal 50% : Indigenous coal 50%) the estimated coal requirement would be as below: Fuel Particulars 5 x 800 MW Per unit TG Heat Rate 1850 kcal/kwh - Boiler Efficiency 87.5% - Station Heat MCR with margin 2209 kcal/kwh - Hourly coal requirement at MCR 2093 TPH 419 TPH Daily coal MCR TPD TPD Annual Coal 85% PLF MTPA 3.11 MTPA 5x800 MW-KSCTPP-FR-TANGEDCO -40- SEC - 3

48 Total traffic for coal (Worst Coal) would be between rakes/day as per Table given below. A coal stock for about Thirty (30) days requirement is considered. Imported coal and Indigenous coal will be transported by Rail through BOBRN type wagons. Description Details BOBRN Permissible Carrying Capacity tonnes 62 Cubic capacity of Wagon Cu.m 57.2 Wagons per rake wagons 59 Net tonnes per rake tonnes 3658 Quantity in tonnes per annum (Worst million 18.4 coal 100% PLF) Tonnes Rakes per year rakes 5030 Rakes per day, on an average rakes 14 Additional 25% rakes 17 Auxiliary fuel for boiler start-up and flame stabilization of the units will be LDO/HSD and HFO. For the purpose of this report a specific auxiliary fuel consumption of 1 ml/kwh is considered. The actual consumption will, however, depend on average daily plant load factor, grid stability, quality of coal etc. High plant load factor can be ensured for the proposed power station and thus, fuel oil consumption can be largely optimized. Fuel oil is planned to be transported to the power plant by road and stored in tanks. 5x800 MW-KSCTPP-FR-TANGEDCO -41- SEC - 3

49 3.5 Power Evacuation: Power generated by the power station shall be stepped up to 765 kv level through three single phase 315 MVA Generator Step-up Transformers (GT) for each unit. Power generated in the generator at terminal voltage of 27KV (depend on generator manufacturer) would be stepped up to 765 kv level by Generator transformer and shall be available in the station switchyard bus. Power from the switchyard would be evacuated through two (2) 765 kv double circuit lines to the nearest 765 kv pooling station, location to be decided by TANTRANSCO the local STU. 3.6 Other Infrastructural Requirements: For a grass root station, availability of infrastructural facilities is essential for successful implementation of the project in a compact time frame. The facilities which are considered essential during early stage of construction are: a. Access roads b. Railway siding. c. Housing facility for the construction staff with supply of water and electricity, community facilities viz. market, housing, school, water works, construction power, health care etc. d. Construction material & critical construction equipments e. Skilled and unskilled manpower f. Telecommunication facility. 5x800 MW-KSCTPP-FR-TANGEDCO -42- SEC - 3

50 Among the above infrastructural facilities, a two-lane access road of heavy duty class emanating from the ECR connecting Ramanathapuram and Vembar is available. Nearest city, Thoothukudi is having infra-structural facilities useful for the proposed power project which is 55 Km from the proposed site. The nearest Domestic airport at Thoothukudi (55 km approx.) /International airport at Madurai (120kms approx.). Long body trailers can be employed for haulage of heavy equipments from port to the plant site. During construction heavy material has to be transported by rail and some by road. It is envisaged that about 10 MVA construction power may be required at 415V level when construction activities takes place simultaneously in all units and station areas of the plant. TANGEDCO shall provide two single circuit 33 kv overhead lines from KADALADI 110KV/33KV SS up to construction site for construction power requirement. At construction site suitable 33/11KV substation with 11KV/415V distribution network with transformers and Distribution board shall be provided to cater the construction power requirement at different locations. Further the Project Proponent shall be instructed to arrange their own emergency DG sets to continue the construction activity during grid failure. 5x800 MW-KSCTPP-FR-TANGEDCO -43- SEC - 3

51 To accommodate personnel of owner, Project Proponent etc. during construction of the project, it is envisaged that some housing facilities such as guest house, bachelor's hostel, residential quarters etc. may have to be developed along with some basic civic amenities. 5x800 MW-KSCTPP-FR-TANGEDCO -44- SEC - 3

52 SITE FEATURES 4.1 Introduction: To ensure efficient and trouble free operation of a thermal power plant throughout the operating life, selection of a proper site with required features, infrastructure and inputs, is always the key factor to optimize on design and cost parameters involved. Integration of the technological equipment and systems with the specific features of the project location is viewed as an important aspect for the site under consideration. A selected site may not always provide the ideal conditions. Engineering solutions are usually possible which can still ensure well designed and operable plants, provided the selected site meets the basic requirements. Again fulfillment of statutory requirements in terms of geographical features, MOE&F norms and priority in land use are the basic criteria for selecting site for thermal power station using fossil fuels. TAMIL NADU GENERATION AND DISTRIBUTION CORPORATION LIMITED (TANGEDCO) has carried out an extensive study to identify suitable locations for setting-up the proposed Thermal Power Plant. TANGEDCO had identified few potential sites in Kadaladi taluk along the Gulf of Mannar for setting up the Project. Land in Kondunallampatti, Tharaikkudi, Kannirajapuram, Narippaiyur, Valinokkam and Siraikkulam villages of Kadaladi Taluk, Ramanathapuram District were identified. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

53 4.2 Justification & Discussion on Selected Site The three potential site details are as given below: The appropriate site is selected based on economic consideration and having minimum impacts on ecology & environment Comparative Details of Sites considered for the proposed project: SL. No. PARAMETERS SITE-A SITE-B SITE-C 1 Land Available (Hectares) 2 No. of Villages Name of village Kondunallam patti Tharaikkudi, Kannirajapuram, Narippaiyur Valinokkam, Siraikkulam Orientation of the land Land type Suitability of Land Distance (aerial) from Sea coast line Marginally irregular boundary Agricultural land Suitable, leveled area Compact in nature Barren land with scrubs and Palm trees Suitable, fairly levelled with minimum undulation Irregular boundary Barren land with scattered scrubs and marginal agricultural land Suitable, fairly levelled with minimum undulation 8 km 2.3 km 0.7 km 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

54 SL. No PARAMETERS SITE-A SITE-B SITE-C Distance (aerial) from 500m HTL Intake/outfall corridor over land Location with respect to District Boundary 7.5km 1.8 km Project Southern boundary overlaps To be routed along the site B with overall approx length of 10 km Lined along Thoothukudi district boundary. Approx route length of 2.3 km Around 2 km from the Thoothukudi district boundary R&R issue Thinly populated No habitation Coal Transport Thoothukudi port then by rail Infrastructural facilities Thoothukudi port then by rail Approx route length of 1 km Center of Ramanathapuram district. Thinly populated Thoothukudi port then by rail Road access Airport access 2.5 km from Sevalpatti- Tharakudi district road Nearest airport Domestic/Intern ational Thoothukudi 70 km / Madurai 100 km 1km from ECR Nearest airport Domestic/In ternational Thoothukudi 55 km/ Madurai 120 km 2km from ECR Nearest airport Domestic/In ternational Thoothukudi 110 km / Madurai 121 km 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

55 SL. No PARAMETERS SITE-A SITE-B SITE-C Railway access Thoothukudi - 49km Ramanathapura m-80km Port access Ecological sensitive locations GOMBR (Gulf of Mannar Biosphere Reserve) GOMNP (Gulf of Mannar National Park) Core area Melselvanoor Keelselvanoor bird sanctuary Chitrangudi bird sanctuary Kanjirankulam Bird sanctuary Nearest port Thoothukudi 66 km Part of site falls in the buffer area Site is 21 km from Kariashuli Tivu and 19 km from Uppu Tanni Tivu Aerial Distance of 24 km Aerial Distance of 24 km Aerial Distance of 26 km Thoothukudi -55km Ramanathap uram-65km Nearest port Thoothukudi 75 km Site is within the buffer area Site is 23 km from Kariashuli Tivu and 11 km from Uppu Tanni Tivu Aerial Distance of 17 km Aerial Distance of 20 km Aerial Distance of 22 km Thoothukudi -85km Ramanathap uram-41km Nearest port Thoothukudi 105 km Site is within the buffer area Site is 12 km from Nalla Tanni Tivu and 5.5 km from Anaipar Tivu Aerial Distance of 12 km Aerial Distance of 21 km Aerial Distance of 22 km 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

56 Site-A: Located in Kondunallampatti, the site is about 80 km from Ramanathapuram. Within the vicinity of 10 km range the above listed sanctuary and national park are not located. However, part of site falls within the buffer area of GOMBR. This site was not considered further for: a) The intake corridor over land to be taken along site-b and the distance works out to around 10km. b) The site has maximum agricultural land. c) The site has few habitats which are likely to cause R&R issues. Site-C: Located in Valinokkam and Siraikkulam about 40 km from Ramanathapuram. This site was not considered for: a) The project site and the intake will be around 5.5 km from the Anaipar Tivu. b) The Intake/outfall location with respect to the site location will be in close proximity with the GOMNP. c) The project site southern part overlaps with 500m HTL. d) The site has some agricultural land and habitat which may cause R&R issues. Site-B: Located in Tharaikkudi, Kannirajapuram and Narippaiyur about 65 km from Ramanathapuram. The site falls within the buffer area of GOMBR. Further assessment on environmental impacts and the requisite management plans shall be pointed out in EIA/EMP study. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

57 From the above mentioned three (3) sites, Site-B is selected due to the following intrinsic merits: a. Project area is spread over 3 villages and the orientation is compact in nature. b. Non Agricultural land. c. NO R&R issue as there is no habitation. d. Land is mostly barren partly with patches of bushes and partly with palm trees. e. As the site identified is near sea shore, the requirements for plant water system could be easily met out. However, it is also reasonably away from the sea coast in compliance with coastal Zone Regulations. f. The site is near the proposed alignment of B.G. Railway line from Kanyakumari to Karaikudi and hence it will facilitate transport of coal from Thoothukudi port to site. g. The site is 1KM away from the existing East coast road h. Closeness to the sea (i.e) about 2.3Km The vicinity map and site location map of the area identified for putting up the station are shown in Drawing Nos.15Z DWG-M-001 and 15Z DWG-M-002 enclosed. In Annexure-4.1 of this report, Land area details of Sites A, B & C are given in brief. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

58 4.3 Feasibility Consideration LAND FEATURES: LAND AVAILABILITY: Total land area required for the Thermal Power Plant is about Ha. Land has been identified in Tharaikkudi, Kannirajapuram and Narippaiyur villages of Kadaladi Taluk, Ramanathapuram District. The land area for the Proposed Power Plant comprises of both private and Government lands. There is no habitation in the proposed Power Plant site, hence no rehabilitation issues. Plot Plan of the proposed Thermal Power Plant is shown in Drawing No. 15Z DWG-M ACCESSIBILITY: The proposed site is on the western side of ECR connecting Ramanathapuram and Vembar. Also The site is near the proposed alignment of B.G. Railway line from Kanyakumari to Karaikudi and hence it will facilitate transport of coal from Thoothukudi port to site. The nearest city/town Thoothukudi at a distance of about 55 km and Ramanathapuram at a distance of about 65 km. The nearest port is Thoothukudi at a distance of 75 km for the site. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

59 FUEL SOURCE & TRANSPORTATION: Feasibility Report Coal, the main fuel for the proposed Thermal Power Plant is envisaged to be imported from Indonesia or any other country to the nearest port Thoothukudi which is 75 km from the proposed site and from there it will be transported to the project site. For Coal connectivity a combination of existing Rail network, proposed new B.G line project and private railway line to the power plant is proposed.the coal from Thoothukudi port will be transported to site by one of the following rail route. i. OPTION I - Utilizing the proposed new alignment of B.G railway line from Kanyakumari to Karaikudi via Ramanathapuram. Coal will be transported by the existing railway line from Thoothukudi Port to Milavittan, then through the proposed B.G railway line which aligns along the southern side of the proposed site and then by private railway line take-off from a location nearer to the Power Plant. Or ii. OPTION II - Utilizing the proposed new alignment of B.G railway line from Thoothukudi to Madurai via Melamarudur. Coal will be transported by the existing railway line from Thoothukudi Port to Milavittan, then through the proposed new alignment of B.G railway line to Melamarudrur. From Melamarudur to the power plant private railway line is proposed. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

60 Details of the Approximate Rail route distance for Coal connectivity are as given below: SL. NO. DESCRIPTION OPTION I OPTION II 1 Through Existing route from Thoothukudi port to Milavittan 2 Through the Proposed new B.G line project 3 Private railway siding Take-off from the proposed BG line 4 Approx. Total route length for coal connectivity 5 Status of proposed BG line Project Route length 11 km The proposed B.G line aligns along the southern side of the proposed plant site connecting Milavittan to Ramanathapuram. Approx route length of 50 km to be utilised in the proposed B.G line. Approx. route length from take- off point to site 4 km 65km Decision is awaited from Railway Board Route length 11 km Milavittan to Melamarudur Approx route length of 14 km to be utilised in the proposed B.G line. Approx. route length from takeoff point (at Milamarudur) to site 40km 65km The proposed alignment has been sanctioned by Railway Board The Coal connectivity details for the site identified for putting up the station in shown in Drawing Nos.15Z DWG-M Coal connectivity Rail route map. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

61 WATER SOURCE & CONVEYANCE: Feasibility Report The consumptive water required for the Power Plant is proposed to be drawn from Gulf of Mannar, the coastal line is at aerial distance of around 2.3 km on the Southern side of the proposed project. Sea water intake pump house will be located off shore and sea water will be pumped to the proposed site through pipe lines over RCC deck. The sea water will be used for condenser cooling and portion of it will be desalinated and used for other purpose. The blow down water from cooling tower and desalination rejects will be discharged back to the Gulf of Mannar. Considering the submergence requirement for the pumps, Intake Pump House to be located at a depth of about 5 m (tentative) will be suitable. Intake and Outfall are proposed to be laid over pile supported RCC deck. A common RCC deck (15 m width) will be provided for both intake and outfall for about 4 km (tentative) and separate RCC deck shall be laid beyond this point for outfall about 1.5 km (tentative). The tentative location is indicated in the Drawing No.15Z DWG-M-003 (sheet 2of2). However, the location of the intake and outfall to be finalised based on the Marine EIA/EMP study & the intake and outfall Modelling study. POWER EVACUATION: Power generated in the Power Plant would be available at 765 kv level and Power from this switchyard would be evacuated through two (2) 765 kv double circuit lines to the 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

62 nearest 765 kv pooling station, location to be decided by TANTRANSCO the local STU. ENVIRONMENTAL ASPECT: The Gulf of Mannar is a large bay in the Indian Ocean that lies along the south-eastern tip of Tamil Nadu extending from Rameswaram in the north to Kanniyakumari in the south. The Gulf of Mannar Biosphere Reserve was set up in 1989 jointly by the Government of India and the Government of Tamil Nadu with a view of protecting marine wildlife and coastal ecosystems that inhabit the 10,500 square kilometers of the reserve. The Gulf of Mannar Marine National Park is a protected area, which is part of the Biosphere Reserve that extends from Rameswaram to Thoothukudi. It consists of 21 small islands varying in size from about 0.5 hectares to 125 hectares and adjacent coral reefs spread over an area of 560 square kilometers. (source: State Environment report of Tamil Nadu JAN-2016) The Kadaladi Talk in Ramanathapuram district is a economically backward district without any major industries and prone to communal disturbances, a power plant of this 5X800 MW capacity will bring in lot of employment opportunities both direct and indirect and will pave away for communal harmony in this area. The effect of the proposed project on environment should be seen in the broader perspective of overall impact on the neighbourhood. The proposed plant site is basically nonagriculture in nature. The site area is free of any forest land and 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

63 there is no historical monument within the vicinity. The plant layout has been prepared keeping in view the CRZ requirements. Three Bird sanctuaries are located in the vicinity Melselvanur-Keelselvanur bird sanctuary at around 17 km, Chitrangudi bird sanctuary and Kanjirankulam bird sanctuary at around 22 km & 20 km respectively from the selected site (Site- B). The GOMNP (Gulf of Mannar National park) Vembar zone Uppu Tanni Tivu is around 11 km and Thoothukudi zone Kariashuli Tivu is around 23 km from the selected project site. The site falls within the buffer area of the GOMBR (Gulf of Mannar Biosphere Reserve). Further assessment on environmental impacts and the requisite management plans shall be pointed out in EIA/EMP study separately. The tentative location of intake / outfall location is around 12 km and 19 km away from the Uppu Tanni Tivu and Kariashuli Tivu respectively in Gulf of Mannar. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 4

64 TECHNICAL FEATURES 5.1 Introduction Tamil Nadu Generation and Distribution Corporation Limited. (TANGEDCO) is planning to set up a coal based 5 x 800 MW capacity power project near Ramanathapuram in the State of Tamil Nadu. The proposal is mooted to deploy the state-of-the-art technology using supercritical steam parameters The basic plant design would consider unitised concept as far as possible. Judicious provisions would be considered for reasonable spare capacities in various systems and system components and interchangeability of equipment/system. Stateof-the-art technology has been considered for design of the proposed project. 5.2 Thermodynamic Cycle The fuel considered for the project is coal from the mines in Indonesia to be transported through Sea cum Rail. The thermodynamic cycle will consist of the supercritical Boiler, the Steam Turbine, the condenser, the condensate extraction and boiler feed systems, the condensate and feed water heaters along with all other necessary equipment for single reheat regenerative feed heating system. 5x800 MW-KSCTPP-FR-TANGEDCO -57- SEC - 5

65 A single reheat steam cycle with regenerative feed heating system is proposed for the project. The typical heat balance for such cycles based on the parameter proposed for the Turbine inlet steam have been presented in Drawing No.15Z DWG-M-004. Heat Balance Diagram is based on zero makeup, 32.5 ºC condenser cooling water inlet temperature with condenser back pressure of 77mm of Hg. As shown in the scheme and heat balance diagram, the main steam from the boiler, after expansion through the HP turbine, would be sent back to the boiler for re-heating. The reheated steam, after expansion through the double flow IP turbine and then through two double flow LP casing would be exhausted into the main condenser. The exhaust steam from the LP turbine would be condensed by circulation of cooling water. Vacuum would be maintained in the condenser by 2x100% (1W+1S) capacity vacuum pumps. The LP feed heating system would consist of three(3) to four(4) stages of low pressure heaters, one(1) gland steam condenser, one(1) drain cooler for the low pressure heater, drain flash and one(1) deaerator. HP feed heating system will consist of two(2) 50% parallel trains of highpressure heaters. However, number of heaters varies from manufacturer to manufacturer. The condensate from the hot well would be extracted by 3x50% capacity condensate extraction pumps (2 working + 1 standby) and pumped to the deaerator through Condensate polishing unit to gland steam condenser, drain cooler and the LP heaters. The feed water after being de-aerated in the deaerator would be pumped to the boiler through the high-pressure heaters. Provision would be 5x800 MW-KSCTPP-FR-TANGEDCO -58- SEC - 5

66 kept for dosing hydrazine solution in the condensate extraction pump discharge and in deaerator feed tank or boiler feed suction line for oxygen scavenging and ph control of the feed condensate steam cycle. For the unit 2x50% turbine driven & 1x50% motor driven BFP with booster pump mounted on common shaft is envisaged. Normally the steam-driven pumps would be in operation. The boiler feed pumps would be provided with lube oil system, automatic leak off and minimum flow re-circulation valves. Motor-driven BFW pump would be provided with modulating variable speed hydraulic coupling. Condensate drain from the HP heaters would be cascaded to the deaerator feed storage tank and the condensate drains from the LP heaters would be cascaded to the condenser through the drain cooler. The auxiliary steam for the proposed power station would be divided into two sub-systems, One Boiler Auxiliary Steam (BAS) and other Turbine Auxiliary Steam (TAS). Both BAS & TAS would receive steam supply from CRH inlet and Outlet line of SH. The auxiliary steam supply system of the unit would supply steam to the deaerators, turbine gland sealing system during light load and start-up conditions. Auxiliary steam will also be supplied for soot blowing, atomisation system etc. Auxiliary Boiler of suitable rating shall be provided in case the BTG supplier requires auxiliary steam for cold start-up of the unit. 5x800 MW-KSCTPP-FR-TANGEDCO -59- SEC - 5

67 The units will also be provided with HP and LP Turbine bypass system for quick start and large load rejections. The turbine generator units would be so designed that these will be capable of cyclic duty and frequent start-ups and shutdowns during the lifetime. The salient features and parameters of major equipment of the 800 MW sets are furnished hereinafter. The details of the units may vary to some extent as per vendors standard product. The basis of technical parameters of the main plant and auxiliary equipment for the 5 x 800 MW thermal power plant are discussed hereunder which describes the general requirements but is not intended to be exhaustive. 5.3 Main Plant & Equipment Turbine Generator Unit : The turbine component and its auxiliaries would be designed and selected to meet the stringent requirements in respect of superior thermal performance, excellent product reliability and operational flexibility. The area provided for the power house is 12.6 acres. The turbine manufacturer will have turbine designed based on modular design approach that divides the turbine into three main parts: High-Pressure (HP) section, Intermediate-Pressure (IP) section and Low-Pressure (LP) section. The proposed turbine will have one HP, one IP (double flow) and two double-flow low-pressure casings. All components will be 5x800 MW-KSCTPP-FR-TANGEDCO -60- SEC - 5

68 selected based on long-proven records and standardized modules. The turbines will be of the tandem compound design. The individual shafts of the cylinders and the generator rotor shaft will be coupled rigidly together and all the shafts will be machined from single forgings. The turbo-generator set would be designed for a maximum throttle steam flow at turbine Valve Wide Open (VWO) condition of 105% of Turbine Maximum Continuous Rating (MCR) flow. Brief technical features of major systems and equipment is given in Annexure-5.1. The HP turbine will be designed with single flow. This will have a double-shell casing consisting of inner casing carrier and barreltype outer casing. Main steam to the HP turbine will be supplied through two(2) combined stop and control valves. The IP-turbine will be designed with double flow. This will have a double-shelled casing with horizontally split inner and outer casing. Reheat steam will be admitted through two(2) combined stop and control valves of the turbine. The valves will be arranged on either side of IP casing. The steam flows to the LP Turbine through a cross-around pipe. The LP-turbine will comprise horizontally split multi shell casing. The outer casing will consist of two end walls, a bracing system, the top half and the sidewalls. The inner casing will be double shell axially split supported by support arms that are bolted to it and that rests on the bracket supports of the bearing pedestals. The bearing pedestals will be mounted on the foundation. They 5x800 MW-KSCTPP-FR-TANGEDCO -61- SEC - 5

69 will carry the shaft seal casings, which shall be joined to the outer casing by means of expansion joints. A fully automatic gland sealing steam supply system will be provided for the TG Set and the turbine driven BFPs. HP & IP turbine shaft glands will be sealed to prevent escape of steam into the atmosphere and the LP turbine glands will be sealed for preventing leakage of atmospheric air into the turbine. Steam will be used for sealing these spring backed labyrinth glands. During start-up and low loads (say 40% load), seal steam will be supplied to the turbine glands from the auxiliary steam header or cold reheat line through a seal steam-regulating valve. During normal operation (above 40% load), the HP and IP turbines will be of self-sealing type and under that condition the auxiliary/crh steam source will be cut off and the leak-off steam from HP and IP glands will be used for sealing the LP glands. The excess leak-off steam shall be led to the condenser. A gland steam condenser will be provided to condense and return to the cycle, all gland leaks off steam including that from BFP turbines. A desuperheating type bypass will be provided during outage of gland steam condenser. 2x100% capacity vapour exhausters will be provided to remove non-condensable gases from the gland steam condenser. The exhaust gases will be led over the TG hall roof level. The turbine will have throttle or nozzle controlled type governing. The steam turbine generator unit will be equipped 5x800 MW-KSCTPP-FR-TANGEDCO -62- SEC - 5

70 with an electro-hydraulic governing system backed up by 100% mechanical-hydraulic or electro-hydraulic control system. HP LP Bypass Station will comprise 60% (BMCR) HP and LP Turbine bypass station to act not only as a protection to the turbine during pressure rise resulting from sudden load throwoff but also to enable operation of the unit at loads lower than the control load. Further HP/LP bypass will permit quick, repeated hot starts of the unit on its tripping. The LP bypass station will be connected to the hot reheat line and discharge the steam into the condenser. The hot reheat steam will be de-superheated by means of condensate injection. The bypass system shall be in operation when the steam turbine is not able to receive the entire steam quantity, e.g. during start-up or in case of a load rejection. The HP and LP bypass stations will be capable of meeting the following requirements: Quick start up of the steam generator from cold, warm & hot conditions. Parallel operation of the bypass with turbine under large load throw-off. House load operation followed by large load throw-off. To keep the steam generator in operation so as to avoid a trip out of the steam generator following full load rejection. Condensing Equipment & Accessories: The function of the condenser is to condense the steam exhausted from the LP cylinders and to produce and maintain as 5x800 MW-KSCTPP-FR-TANGEDCO -63- SEC - 5

71 high a vacuum as possible in order to increase the enthalpy drop, which can be utilised in the turbine. The condenser will be of single-flow box-type surface condenser with water boxes on each end for 800 MW sets. The steam space will be of rectangular cross-section to achieve optimum utilization of the enclosed volume for the necessary condensing surface. The condenser will be located below the LP turbine and form an integral part of it. Each condenser unit would be transverse mounted and would condense exhaust steam by circulation of cooling water (inlet temperature 32.5 C max.) in a recirculating cooling water system using wet type cooling tower. Condenser outlet water temperature may be maintained within 42.5 C. Sea water would be the cooling medium in the condenser and other auxiliary coolers. Condenser tube shall be welded titanium ASME B-338 GR II and tube support plates shall be carbon steel. Cathodic protection with Zn or Al sacrificial anode would be provided, if required. The condenser would be designed as per HEI code or equivalent. The heat load of the condenser will correspond to the turbine operating condition with VWO having 105% MCR steam flow, 1.5% make-up, 85% tube cleanliness factor and a maximum cooling water inlet temperature of 32.5 C to maintain rated condenser pressure of 77 mm of Hg (absolute). The condenser should also be capable of accepting full HP-LP bypass steam flow safely without undue pressure rise, vibration, noise or other detrimental effects. Oxygen content of 5x800 MW-KSCTPP-FR-TANGEDCO -64- SEC - 5

72 condensate leaving condenser hot well will not exceed cc per litre over the entire load range. Lube Oil System: The oil system will supply oil for lubrication and cooling of turbine and generator bearings, and to the hydraulic shaft turning gear during start-up and shutdown. This system will be provided with AC & DC powered oil pumps. To improve lubrication of the bearings during start-up and shutdown, a jacking oil system will be installed which also supplies motive oil to the hydraulic turning gear with hydrometric gear motor. A separate, self-contained high pressure fluid system with dedicated pumps will be provided for lubrication & cooling of turbine & generator bearings. The Lube oil system will specifically include the following: The main oil pump will be centrifugal/gear type. The turbine shaft will directly drive it. It will have sufficient capacity to handle lube oil requirement of the bearings and emergency seal oil requirements. 2 x 100% AC Aux. oil pumps for start-up, slowdown of TG unit and as standby to MOP for automatic operation. These pumps will be in service during start up till the main oil pump takes over the supply. 1 x 100% DC emergency oil pump for meeting lube oil requirements of bearings during emergency with automatic starting on low lube oil pressure preset value. 5x800 MW-KSCTPP-FR-TANGEDCO -65- SEC - 5

73 One (1x100%) each AC & DC motor jacking oil pumps will be provided to lift the rotor at the bearing during turning gear operation. Each unit will be provided with an oil tank of sufficient capacity for oil changes. 2x100% duty vapour extraction fans. The 2x100% capacity oil coolers will be provided for oil cooling. A lube oil purification unit will be permanently installed for each unit for the total oil charge on a continuous basis. Turbine Control Fluid System: For the governing and control system of the turbine a complete self-contained control fluid system with oil pumps will be provided. Fire resistant fluid will be employed to eliminate fire hazards. The system will comprise: A control fluid reservoir of adequate capacity to ensure fluid supply. 2 x 100% AC motor driven pumps to pump the fire resistant fluid from the reservoir. 2 x 100% capacity control fluid coolers designed for service with DM water. A control fluid purifying unit will be provided for the turbo-set for purifying at least 20% of the total oil charge in the system per hour on a continuous bypass basis. 2x100% capacity AC motor driven purification pumps to circulate oil through purification system will be provided. Necessary filters, strainers, piping, fittings, valves and instruments shall be provided. 5x800 MW-KSCTPP-FR-TANGEDCO -66- SEC - 5

74 Air Extraction: The unit will comprise 2x100% (1 working + 1 standby) vacuum pumps along with all accessories and instrumentation for condenser air evacuation. The vacuum pumps and accessories will be used to create vacuum by removing air and noncondensable gases from steam condenser during plant operation. Vacuum pumps will be of single/two-stage liquid ring type with both stages (if two-stage pump is selected) mounted on a common shaft. Vacuum pumps will be sized as per latest HEI requirements. Condensate Extraction Pumps: The condensate/feed water cycle would also comprise 3x50% capacity motor-driven, vertical condensate extraction pumps of CAN-type construction. Connection between condenser and each pump will be through a block valve and removable strainer. The pumps will discharge through check valve and motor operated stop valves into a common discharge header. Connection for condensate supply to the following major services will be tapped off from this condensate discharge header. a. LP bypass desuperheating spray b. Turbine exhaust hood spray c. Gland sealing system desuperheating Condensate will then pass in series through the gland steam condenser and drain cooler before being passed through the low pressure feed water heaters. 5x800 MW-KSCTPP-FR-TANGEDCO -67- SEC - 5

75 Boiler Feed Water Pumps: The feed water heating system will also comprise one(1) motordriven (50% capacity) and two(2) turbine-driven (50% capacity) boiler feed water pumps. The head, capacity and net positive suction head (NPSH) would be so selected as to permit parallel operation at all loads and be compatible with the heat cycle considered to meet the boiler MCR without encroaching on normal margins. Booster pumps may be considered to ensure appropriate head at pump inlet. The pumps will be provided with mechanical seal, flushing arrangement as per API 610. The supply would be complete with and inclusive of variable speed hydraulic coupling, lube oil system, automatic leak-off, minimum flow recirculation valves, bypass valves, base plates, foundation bolts, couplings, 11 kv, 3 ph, 50 Hz electric motor drive. The regenerative feed heating system would comprise vertical or horizontal shell and tube-type high pressure feed water heaters with bypass arrangement. Three(3)/four(4) stage horizontal U- tube type low pressure heaters equipped with drain cooling and condensing zones and individual bypass system is envisaged. Besides these, separate drain cooler, gland steam condenser etc. as per suppliers' standard, horizontal spray or spray-cumtray type deaerator with integral vent condenser to limit oxygen content to a maximum limit of cc/litre at all operating conditions with minimum loss of steam are envisaged. The storage tank should be adequately sized to accommodate at least 10 minutes water requirement to provide feed water to respective boiler at the BMCR condition. The two (2x50%) or 5x800 MW-KSCTPP-FR-TANGEDCO -68- SEC - 5

76 three (3x33%) nos. high-pressure heaters in parallel path will be of horizontal/vertical U-tube type having desuperheating, condensing and drain cooling zones. All steel construction of condensate/feed water wetted surfaces is desired to facilitate uniform chemical conditioning of steam-condensate-feed water system. Steam Generators: Super Critical Pressure ( SCP ) power plant is envisaged with a view to ensure better plant efficiency; minimizing basic fuel consumption; and most important criteria being the drastic reduction of emission quantities of SO x, NO x, CO 2 and particulate matters etc. The SCP technology has been presently accepted in India and is adopted in some of the major thermal power plants. The area provided for the boiler and mill bay is 14 acres. Furnace Type: Two-pass/tower type spiral wall or vertical wall type are normally considered. The principal concern with a variable-pressure/sliding pressure super critical-pressure design is the requirement for oncethrough operation. The mass flow in the furnace-wall tubes must be sufficiently high to avoid excessive metal temperatures and uneven steam outlet temperatures when operating at super critical pressure at higher boiler loads. The draft system comprises of two(2) nos of FD fans each rated 5x800 MW-KSCTPP-FR-TANGEDCO -69- SEC - 5

77 for 60% of BMCR capacity. Two(2) Induced Draft (ID) Fans each rated at 60% of BMCR flow will be axial inlet vane control type with variable frequency drive arrangement. With cold primary air system, it is possible to reduce the capacity of Primary Air Fans (PAF) compared to hot primary air system. Cold primary air system is adopted in all cases. Two PA fans with 60% capacity are considered. Pulverized Fuel Preparation System: For firing coal pulverizers of slow speed large capacity bowl mills will be provided having low auxiliary power consumption; and relatively high life expectancy of grinding parts and armour plating. The mills size and numbers will be selected such that on an average one mill remains standby while one of the mill is under maintenance. Considering the grinding fineness required, it is suggested equipping the mill with rotating classifiers having speed adjustment to control grinding fineness. The firing system will employ latest the state-of-the-art burners and permit load variation from 40 to 100% BMCR without use of support fuel. The ratio of fuel and air flow will be controlled. Due to sufficient burner wall distance and the burner swirl direction, operation with low excess air is possible without the risk of wall damage. Start-up Fuel System: The fuel oil system will be provided for boiler start up; and for flame stabilization during low load operation with or without coal 5x800 MW-KSCTPP-FR-TANGEDCO -70- SEC - 5

78 Firing. Two (2) types of fuel oils will be used. Feasibility Report Light Diesel Oil (LDO/HSD) for boiler start-up (upto 10% of BMCR) Heavy Fuel Oil (HFO) for low load operation and flame stabilization (40% of BMCR), as necessary. Electrostatic Precipitators: It is proposed to install high efficiency electrostatic precipitators having an efficiency that will limit the outlet emission to 30 mg/nm 3 while the boiler is operating at its BMCR, firing worst coal having maximum ash content. The electrostatic precipitators will have six(6) gas streams, isolated from each other on the electrical as well as gas side and will be provided with gas tight dampers at inlets and outlets of each stream, so as to allow maintenance to be carried out safely on the faulty stream, while the unit is working. Electrostatic precipitator will be provided with micro-processor based programmable type rapper control system and ESP management system to ensure the safe and optimum operation of ESP. ESP transformer rectifier sets will use high fire point oil as the cooling medium. The dust collection hoppers at all strategic locations will have a minimum storage capacity of eight(8) hours. The hoppers will have heating arrangements to prevent ash sticking to the sloping sides and down pipes. Level indicators to indicate and trip the ESP in case of high ash levels in the ash hoppers, which will jeopardize the safety of ESP otherwise. The area provided for the ESP is 12 acres. 5x800 MW-KSCTPP-FR-TANGEDCO -71- SEC - 5

79 Flue Gas Desulphurising System (FGD): Feasibility Report FGD system, to be installed behind the chimney. The design and layout of steam generator and its auxiliaries will be such that a wet flue gas desulphurisation system can be installed, taking suction from duct after ID fan and feeding the de sulphurised flue gases back to the chimney with provision for bypassing the FGD system. The FGD system would require around 0.2 million tonnes of limestone per year. The generation of Gypsum is around 0.3 million tonnes per year. Closed storage area with storing capacity for 30 days is provided for the limestone and gypsum in FGD material handling area located at the eastern boundary of the plant. The total area provided for the FGD system is around 17 acres. In addition, an open storage area of 50 acres is provided within the plan boundary near the ash dyke for the disposal of Gypsum. Chimney: Total 3 (Three) stacks with stack height of 275 m (two twin flue and one single flue stack) is envisaged for the proposed units. 5.4 Auxiliary System The philosophy of design of the auxiliary system would be predominantly guided by the land features, technology, basic parameters, infrastructure etc. The other facilities to be developed are, coal transportation from Tuticorin by railway, coal storage and handling systems, fuel oil system, 765 kv switchyard, ash handling facility, etc. 5x800 MW-KSCTPP-FR-TANGEDCO -72- SEC - 5

80 All the systems and system components would be designed for simplicity of operation and ease of maintenance so as to call for minimum manual labour and low degree of supervision. System redundancy would be provided as per good engineering practices. Brief technical features of Major Systems & Equipment are enclosed as Annexure-5.1. Plant Water System: The consumptive water requirement of the proposed 5x800 MW station is of the order of m 3 /hr (approx) (7839 m3/hr per unit) to be met by drawal of water through an intake well with pump house to be constructed on off-shore. The cooling water system is based on recirculating cooling system using wet type Natural Draft Cooling Tower (NDCT) for the condenser and auxiliary equipment cooling circuit. Based on the available sea water analysis it is envisaged that a cycle of concentration of 1.3 would be achieved. The total area provided for the plant water system is around 138 acres. Sea water is the main source of water for the proposed power station. It is planned to draw m 3 /hr of water from sea through an intake pump house. For the proposed 5x800 MW station the total sea water requirement is estimated on the basis of about 1% heat cycle make-up, make-up to cooling towers usually associated with 5x800 MW-KSCTPP-FR-TANGEDCO -73- SEC - 5

81 average daily plant load apportioned on hourly basis and other consumptive requirements like potable water, RO-DM make up, sealing water, Service water, HVAC makeup etc. It is proposed to utilise cooling tower blowdown in ash handling plant slurry disposal system. The breakdown is detailed in Annexure-3.2 furnished earlier and the water balance diagram is given in Drawing No.15Z DWG-M-009. It is envisaged that Six (6) (4W + 2S) nos. of m 3 /hr capacity intake pumps would be installed in the sea water pump house. Sea water from the intake system would be pumped to CT forebay as CT makeup water, Electro-chlorination plant and a part of sea water will be clarified in the DAF Clarifier at site to remove the suspended solid. Clarified water from DAF Clarifier would be stored in an intermittent clarified water storage tank. Sea water from cooling tower basin would be pumped to condenser. Water requirement for Desalination plant would be pumped from intermittent clarified water storage tank by use of Desalination plant feed pumps two (2) nos. (1W+1S). Of these, cooling tower make-up is the largest quantity involved. Considering the ambient parameters and gestation period, Natural Draft Cooling Towers (NDCT) have been proposed. Apart from the condenser cooling, other auxiliary cooling will be achieved by circulating sea water by a separate set of auxiliary cooling water (ACW) pumps. These ACW pumps 5x800 MW-KSCTPP-FR-TANGEDCO -74- SEC - 5

82 would also be located in the same CW pump house. Sea water in auxiliary cooling water system would be utilised as a secondary circuit with DM water as a primary circuit of plate type heat exchanger to cool the auxiliary coolers. Cooling water in circulation estimated for the units would include the requirement of auxiliary cooling circuit. The make-up water requirement for the Natural Draft Cooling Towers (NDCT) at full load will be around m 3 /hr (6625 m 3 /hr per unit). The cooling tower blow down is expected to be about m 3 /hr. For 5x800 MW station fifteen (15) nos. [2W + 1S per unit] CW pumps and ten (10) nos. [1W + 1S per unit] ACW pumps are envisaged. DM Closed Cycle Cooling Water Pumps Four(4) [3 working + 1 standby] per unit. The desalinated / product water from desalination plant would meet the following requirements: BWRO-DM plant Sealing and cooling water for ash handling plant HVAC System F.G.D system Potable water for plant & township Service water requirements Coal Handling Plant Dust suppression Fire protection system Fire water requirement would be supplied from the desalinated / product water storage tank and a built-in dead storage would be provided as per Tariff Advisory Committee (TAC) requirement. 5x800 MW-KSCTPP-FR-TANGEDCO -75- SEC - 5

83 For potable water supply to the project, a separate set of pumps drawing water from desalinated / product water storage tank and with necessary chlorine dozing is envisaged. An overhead tank of about 50 m 3 capacity would be located at the top of powerhouse and drinking water would be supplied to different consumption points through piping. On apportioned basis about 100 litre of potable water may need to be supplied per person per day. BWRO permeate water would be supplied to the demineralisation plant, which would comprise of three(3) (2W+1S) chains of 90 m 3 /hr (each). DM water would then be stored for 24 hours in Four (4) rubber lined mild steel DM water storage tanks of each 1100 m 3 capacity, located near DM Plant. The proposed DM plant along with the neutralisation pit, acid/alkali handling system would be located close to the DM water consumption point to optimize on DM water pipeline. DM water from the DM water storage tanks would thereafter be pumped to the condensate storage tanks located near the boiler area. Five(5) condensate storage tanks each of 500 m 3 capacity is envisaged. Water from this tank will be supplied as heat cycle make-up and to the chemical feed system, H 2 generation plant. Make-up requirements for CCCW system and condensate polishing system. Demineralisation Plant & Heat Cycle Make-up System: Assuming average 1.0% make-up for the heat cycle and accounting for four hours regeneration time, three(3) 5x800 MW-KSCTPP-FR-TANGEDCO -76- SEC - 5

84 demineralising chains of 90m 3 /hr feed flow capacity each have been envisaged for the proposed unit. In the proposed DM plant two streams will be in operation and one stream will be as standby. DM plant will also supply heat cycle make-up, the make-up requirement for primary water circuit of stator cooling system, chemical feed system, CPU make-up and DM water requirement for the hydrogen generation plant. Desalinated/product water would be pumped to the RO-DM plant for demineralisation. In the RO-DM plant, Desalinated/product water will be passed through RO plant (Stage-II) and then to mixed bed exchangers. The demineralised water will be stored in DM water storage tanks. Acid and alkali handling, storage and feeding system will be installed for the DM plant resin regeneration. The DM water produced in the plant would then be taken to Four (4) DM water storage tanks, each of 1100 m 3 capacity to meet the total requirement in case of any exigency. DM water from the storage tanks would be transferred to unit condensate storage tanks by 2 x 100% capacity DM transfer pumps. Service Water System: Service water for the project would be used for floor washing, air filter cleaning and other non-priority items etc., Desalinated/product water shall be taken to an overhead tank for onward distribution to above consumption points. 5x800 MW-KSCTPP-FR-TANGEDCO -77- SEC - 5

85 Coal Handling System: For the purpose of equipment selection the worst coal combination (imported 50% & indigenous 50%) has been adopted. The total area provided for the Coal handling system including MGR system is around 148 acres. The scheme of the proposed Coal Handling System is shown in Drawing No.15Z DWG-M-006. Adequate redundancy has been adopted to ensure uninterrupted operation of the system. The Coal Handling system to be designed based on the worst coal (50:50). i) Gross calorific value 4221 kcal/kg ii) Hourly coal consumption 2093 TPH 419 TPH per unit iii) Max. daily consumption of coal at MCR TPD TPD per unit iv) Annual requirement for MTPA proposed 85% PLF 3.11 MTPA per unit v) Maximum size of coal delivered (-) 50mm at plant end vi) Mode of coal transportation By railway from Tuticorin Port. Coal for the proposed station would be eventually available from Indonesia. The coal in (-) 50 mm size would be transported to the plant site in rake loads. To operate the station at MCR, rakes/day loads of coal need to be received. With the above in view 24 hr operation of coal receiving facility is envisaged. To estimate the design capacity of conveyors and coal handling system a margin of 20% may be considered towards presence of shale in raw coal. The bunker capacity for the unit is 5x800 MW-KSCTPP-FR-TANGEDCO -78- SEC - 5

86 considered to be 14-hours. The balance of plant and equipment of CHP would be designed for three-shift operation for the proposed station which will take care of outage requirement and running maintenance. The handling capacity of receiving and stacking facilities for the proposed power is of 4500 TPH two streams (1W + 1S) rated capacity. However, figures on coal consumption and conveyor capacity may be revised at DPR stage as per available input data at that time. Merry-go-round system is envisaged for the proposed project. Three (3) nos. Track hoppers is provided for handling the 17 rakes/day of BOBRN type wagons. The coal from the hoppers would be fed to the crusher house, crushed to the size of (-)25 mm. The coal stack would be equipped with two (2) nos. reversible stackercum-reclaimer and two (2) nos. single direction stacker-cumreclaimer with stacking rated capacity of 4500 TPH and reclaiming rated capacity of 2000 TPH. The stacker-cumreclaimer would be rail-mounted, electrically-driven unit with 50 m boom length having 270 slewing and adequate luffing provision to stack the coal upto a height of 9 m and reclaiming the same afterwards. In the normal route coal can be directly taken to the power-house bypassing the coal stack. Coal Bunker conveying system, the Unit 1,2 & 3 will be provided with separate twin stream conveyor system with rated capacity 2000 TPH form the stock pile to bunker. Unit 4 & 5 will have another independent twin stream conveyor system with rated capacity 2000 TPH. Interchange coal feed facility is also provided for the two independent conveying system. 5x800 MW-KSCTPP-FR-TANGEDCO -79- SEC - 5

87 Crushed coal would be transported to the bunkers via the inclined conveyors and the bunker level conveyors. Bunkers would have a storage capacity of about 14 hours fuel requirement for the boiler. The bunkers will be provided with rod and slide gates, arch breakers, etc. to facilitate operation. Necessary belt weighing at bunker level conveyors, electromechanical and capacitance type level indicators, fuel sampling units, flap gates etc. would be provided in the system as required. Dust extraction and suppression system will be provided for all the coal transfer points to control the fugitive emissions. Special precautions will be taken for pollution control by providing dust extraction and dust suppression systems at different transfer points and ventilation system for underground tunnels. In addition, roof extraction fans will be provided in key areas like boiler bunker floors. Pressurized ventilation system with unitary air filtration unit will be provided for control room and MCC buildings. Necessary water distribution network for drinking water with pumps, piping, tanks, valves etc. will be provided for distributing water at all transfer points, control rooms etc. Similarly, service water network will be provided. A centralised control room with microprocessor based control system is envisaged for operation of the Coal Handling Plant. Except locally controlled equipment like dust extraction/dust suppression/ventilation equipment, sump pumps, water distribution systems etc. all other in-line equipment would have provision of remote control. However, provision of local control 5x800 MW-KSCTPP-FR-TANGEDCO -80- SEC - 5

88 would also be provided. All necessary interlocks, control panels, MCCs, mimic diagrams etc. would be provided in the main control room for safe and reliable operation of the Coal Handling Plant. The major equipment for the proposed project are listed below:- 1. Track Hopper : 3 nos. 2. Rotary plow feeder : Twelve (12) nos. 3. Belt conveyors : Coal stacking stream conveyors of 4500TPH. Reclaiming and bunker supply stream conveyors of 2000 TPH 4. Stacker-cum-reclaimer : Four(4) Nos. with stacking capacity of 4500 TPH and Reclaiming capacity of 2000 TPH. 5. Crushers : Four(4) Nos. 6. Metal detectors : Ten(10) Nos. 7. ILMS : Twelve(12) Nos. 8. Belt weighers :Fourteen (14) Nos. 9. Coal sampling unit : Three(2) Nos. 10. Flap gates, rack & pinion gates, etc. : As required. 11. Level indicators : Electronic type. 12. Chute liners and chute : One lot supporting structures 13. Bulldozer : Six(6) Nos. 5x800 MW-KSCTPP-FR-TANGEDCO -81- SEC - 5

89 Ash Handling System: To meet the requirement of the prevailing environmental norms of the Tamil Nadu Pollution Control Board (TNPCB) and Central Pollution Control Board (CPCB) guideline, the system considers Dry collection and disposal of Fly Ash, Dry extraction of bottom ash. Ash will be primarily disposed by truck to end users as far as possible. Besides provision will be made to transport fly ash (only during emergency) and Bottom ash through pipe line to the ash dump area. The total area provided for the Ash handling system is around 5 acres. The ash dyke area is around 522 acres. The quantum of ash generation would depend on the plant load factor and the quality of coal being fed. In keeping with the designed system capacity envisaged for CHP, worst coal with ash percentage of 26% is used for equipment selection of the Ash Handling Plant. It has been estimated that about 544 tons/hr (max.) of ash would be generated from the proposed project considering 5 units. Assuming the ratio of fly ash to bottom ash as 80:20, usually adopted for design of such application, about 22 tons/hr of bottom ash and 87 tons/hr fly ash is required to be removed from each unit. Ash generation rate being moderate, intermittent ash removal arrangement with necessary storage hoppers (i.e. bottom ash hoppers, economiser/air pre-heater/esp hoppers) to hold ash for 8 hours is envisaged. Bottom ash evacuation in 4 -hours per shift and fly ash evacuation in 4-4 1/2 hours per shift has been considered. 5x800 MW-KSCTPP-FR-TANGEDCO -82- SEC - 5

90 In Drawing No. 15Z DWG-M-007, the scheme proposed for the Ash Handling Plant of the project is shown. The scheme proposes Dry extraction and disposal of bottom ash via Dry conveyor, crusher, pneumatic conveying system bottom ash silo. The design capacity of bottom ash evacuation system would be 45 TPH for each boiler. Fly ash from ESP, air heater and economiser collection hoppers and stack hoppers would be conveyed through vacuum system to the intermediate surge hoppers from where ash would be transmitted by pneumatic pressurised system to the fly ash storage silo. As shown in the sketch, conveying air compressors would be used to transfer fly ash to the silos. De-ashing from fly ash hoppers would operate on an auto sequence mode with total operation time spanning 4 to 4.5 hours in a shift. Four(4) streams of pneumatic conveying system of capacity about 100 Tons/hr each have been considered for each boiler. The ash would be conveyed through pressure conveying system upto the fly ash silo located near the boundary of the plant. The design capacity of the pressure conveying system would be optimized to suit this requirement. Bottom and dry fly ash would thereafter be transported in covered trucks from the respective silos for end use. An additional spare nozzle may be provided below the fly ash storage silo for slurry disposal lean mode of disposal which is around 20% ash concentration on volumetric basis. Normally, dry disposal mode would be operational. Provision is kept for selling ash from the dry ash disposal spout of silo to the possible users. A small quantity of water will be sprinkled to moisten the 5x800 MW-KSCTPP-FR-TANGEDCO -83- SEC - 5

91 ash in the silo unloaders prior to loading in the trucks for truck disposal. For the purpose of the present project report the above system has been considered for working out the project cost. The Ash Handling System control room will be located adjacent to ESP control room for ease of operation. Fluidizing Air System: Continuous supply of fluidizing air during ash evacuation has been envisaged in all the hoppers of the ESP and the stack to facilitate smooth and effective ash flow. For this, fluidizing air blowers of adequate capacity (2x100%) and pressure would be provided. The fluidizing air system would be complete in all respects with necessary piping, valves and instruments to ensure satisfactory system operation. MCC & Control Panel: 415 V MCC (Motor Control Centre) and control panel for the Ash Handling Plant would be located inside a separate room annexed to the ESP control room. Ash Handling System operation can be done in automatic sequential manner and/or remote manual mode from the PLC based control panel. 5x800 MW-KSCTPP-FR-TANGEDCO -84- SEC - 5

92 Fuel Oil Handling System: The fuel oil handling system would comprise receiving, storage, pumping and heating of both HFO and LDO. Oil would be brought to the plant in either rail wagons or by road tankers from nearby depots. Two(2) HFO storage tanks of 5000 m 3 and two(2) LDO storage tanks of 1250 m 3 are envisaged for the station. The system would be complete with unloading pumps, filters, pressurizing pumps, pipeline, instruments etc. The total area provided for the Fuel oil handling system is around 4 acres. Ventilation & Airconditioning System: Right environment for operation and maintenance of the plant as well as for proper functioning of the equipment, controls and accessories is an important aspect which has been given due consideration in the proposed Ventilation and Air Conditioning System. Ventilation System: Adequate ventilation system has been considered for the powerhouse building, Central Control Building, ESP control building, Air Compressor House, Blower room for Ash Silo & Vacuum Fly Ash System, Switchyard Control Building and other areas like A/C plant room, Switch gear room for Cooling Towers, DM plant building, CW Treatment Building, Chemical House, DG Building, Hydrogen Generation Plant, Elevator Machine rooms and various pump houses like CW/ACW pump house, Raw Water pump house, Ash Slurry pump house, Clarified Water pump house, Fuel Oil Unloading and Pressurizing pump house etc. with 5x800 MW-KSCTPP-FR-TANGEDCO -85- SEC - 5

93 their associated Electrical rooms, Workshop and Store, Fire Station Building, Kitchen/Pantry and Toilet areas of Canteen Building, Service building and Administrative Building etc. to achieve the following :- i) Dust-free comfortable working environment. ii) Scavenging out structural heat gain and heat load from various equipment, hot pipes, lighting etc. iii) Dilution of air polluted due to generation of obnoxious & hazardous gaseous/aerosol contaminants like acid/chemical fumes, dusts etc. Ventilation system proposed for important areas are described below: a. Powerhouse and Central Control Building Supply/exhaust ventilation system with evaporative cooling has been recommended for the powerhouse building. Ambient air would be drawn through air inlet louver, automatically cleanable water flooded type SS mesh filters, water wetted fill deck and moisture eliminator and will be supplied by means of centrifugal fans to powerhouse through ducting and grilles to achieve proper distribution. The sprayed water over the SS mesh filter will be recirculated by means of centrifugal pumps, piping, valves and other accessories. Similarly, water dripped over the Fill Deck will also be re-circulated by means of centrifugal pumps, piping, valves and other accessories. 'Exhaust' system consists of axial flow wall/roof-mounted exhaust fans with rain protection cowl/hood, short 5x800 MW-KSCTPP-FR-TANGEDCO -86- SEC - 5

94 ductwork, etc. Part of the supplied air will be exhausted and the rest will ex-filtrate through the various openings in the structure, preventing infiltration of dusty air. Various non air conditioned rooms in the Central Control Building e.g., cable spreader room, switchgear & MCC rooms, SWAS wet panel rooms and Battery Charger rooms etc. will be ventilated by means of the same Evaporative Cooling units for Power House. Exhaust ventilation system will be provided for the Battery Rooms to evacuate acid fumes and hydrogen. Bifurcated type exhaust fans will be employed for this purpose. Coal tripper floors are proposed to be provided with exhaust system to eliminate building-up of hazardous gases like carbon monoxide, methane etc. Pressurized Ventilation system will be effected for the Elevator Machine rooms by means of wall mounted Fan- Filter units and back draft dampers. All toilets will be ventilated by providing wall mounted exhaust fans. b. ESP and AHP Control Buildings For ventilation of these building (except the control room), ambient air will be drawn through unitary air filtration unit comprising fresh air intake louvers, automatically cleanable SS mesh filters (with water spray) and moisture eliminator 5x800 MW-KSCTPP-FR-TANGEDCO -87- SEC - 5

95 and supplied to the space by means of centrifugal fans. Water sprayed over the filter will be re-circulated by means of centrifugal pumps. In addition to filter cleaning, the water spray will have an evaporative cooling effect too. This will produce some cooling effect as an additional advantage. The supplied air will be exhausted through wall mounted gravity operated dampers (Back Draft Dampers) to maintain an overpressure of 1-2 mm of water column to reduce dust ingress. c. Other Buildings Other buildings like Air Compressor House, A/C plant room, DM plant building, CW Treatment Building, Chemical House, DG Building, MCC/Switchgear room of Switchyard Control Building, Hydrogen Generation Plant Building, Aeration Blower room for Ash Silo and Blower Room for Vacuum Fly Ash System, Various pump houses, like CW/ACW pump house, Raw Water pump house, Ash Water pump house, Ash Slurry pump house, Clarified Water pump house, Fuel Oil Unloading and Pressurizing pump house etc. with their associated Electrical rooms, Workshop and Store, Kitchen/ Pantry and Toilet areas of Canteen Building, Service Building and Administrative Building etc. will be ventilated by means of dry system comprising axial flow fans, dry filter (wherever required), cowls, ducting (wherever required), gravity dampers (wherever required) etc. Inside 5x800 MW-KSCTPP-FR-TANGEDCO -88- SEC - 5

96 dry bulb temperature (DBT) is expected to be higher than ambient by about 3 C. Air Conditioning System: Various control rooms in power station, housing a group of sophisticated and precision control panels and desks call for controlled environment for proper functioning and for personnel comfort. Some other facilities like Administrative Building, Service Building, Canteen Dining Hall etc will also call for comfortable environment for the occupants. The following areas are proposed to be air conditioned:- a. Control room, control equipment room, Shift Charge Engineers rooms, computer room, UPS room SWAS dry panel room, CPU Control room, Laboratory room, located in the Central Control Building/Turbine Building. b. Electrostatic precipitator control room c. AHP Control Room d. Coal Handling Plant Control Room e. DM plant control room, office and Laboratory area f. Office areas, lecture rooms etc. in the service building g. Switchyard Control Room h. Weighbridge Control Room i. Fire Station Control Room j. AC Plant Control Room k. Hydrogen Generation Plant Control Room l. Other Control rooms housing PLC panels m. Different floors of the Administrative Building 5x800 MW-KSCTPP-FR-TANGEDCO -89- SEC - 5

97 n. Dining Hall of Canteen Building To cater to the above requirements the following systems are 5x800 MW-KSCTPP-FR-TANGEDCO -90- SEC - 5 proposed:- i) A central chilled water plant to cater to the air conditioning requirement for the Central Control Building and Service Building, comprising Vapour compression Chiller and standby Screw Chillers, condenser cooling water circulating pumps, cooling towers, chilled water circulating pumps, cooling water and Chilled water piping with valves, accessories, fittings, supports, insulation as applicable, steam piping with fittings, supports, insulation, PRDS and associated Electrical items etc. has been envisaged. The chilled water produced in this central Chilled water plant will be circulated through the coils of individual air handling units for the respective air conditioned rooms/areas. This Central Air Conditioning System will be operated and controlled from the AC plant Control room DDC panels and two nos. Workstation PCs. ii) iii) Individual Water Cooled Precision Air Conditioners (PAC) will be provided for AHP Control room and DM plant Control Room, Office and Laboratory. Condenser Cooling water will be supplied to such PAC units from the Plant ACW system. Such PAC units will be operated and controlled from their built-in Microprocessor based Control console. Individual Air Cooled Precision Air Conditioners (PAC) will be provided for Switch Yard Control Room and CHP Control room. Such PAC units will be operated and controlled from their built-in Microprocessor based Control console. iv) Air Cooled Ductable Split/ Packaged Air Conditioners will be provided for Dining Hall of the Canteen Building and Administrative Building. These Air Conditioners will be operated and controlled from their built-in Microprocessor based Control Console/ hand operated Remote Control Panels.

98 v) Air Cooled Non-Ductable Split Air Conditioners will cater to the AC requirement of ESP Control room, Weighbridge Control room, Fire Station Building Control room, Hydrogen Generation Plant Control room, AC plant Control room and other small control rooms housing PLC panels. These Air Conditioners will be operated and controlled from their individual hand operated Remote Control Panels. Compressed Air System: For the proposed units Twelve (12) (6 Nos (5W+1S) of IA and 6 Nos.(5W+1S) of PA) compressors with 55 Nm 3 /min would be provided. The instrument air compressors will be oil-free type, and will be provided with individual air receivers to absorb pressure pulsation and for acting as reserve supply of compressed air to permit continued operation following failure of the operating compressor until the standby one comes into service. A desiccant-type dryer unit with 100% standby, automatic regeneration facility etc. will be provided for each unit for supply of clean, dry air to Control and Instrumentation System. Compressor house with area of 90mX40m is provided. The station service air requirement for normal cleaning purposes, atomising air medium for warm-up guns and igniters, motive power for burner drive mechanism, emergency drive for air pre-heater (in case of regenerative type) etc. will be met from separate plant-air compressors. The plant air compressors would be identical to the instrument air compressors and would run in a manner, similar to that described above for the instrument air compressors. Capacities of all the instrument and plant air compressors selected would be similar for both the 5x800 MW-KSCTPP-FR-TANGEDCO -91- SEC - 5

99 phases, so as to achieve interchange-ability of parts. Independent air receivers will be provided for each compressor. Plant service air system will have suitable inter-connection with the instrument air header for augmenting instrument air supply in emergency. Fire Protection System: For protection of the plant against fire, all yards and plant will be protected by any one or a combination of the following 5x800 MW-KSCTPP-FR-TANGEDCO -92- SEC - 5 systems:- a. Hydrant system b. Automatic high velocity and medium velocity sprinkler system c. HV & MV water spray (Emulsifier system) d. Fixed foam system for HFO & LDO tanks e. Portable and mobile chemical extinguishers f. Inert gas flooding system for Control room, control equipment area, inverter and battery rooms The system will be designed as per the guidelines of Tariff Advisory Committee (TAC) of the Insurance Association of India. Applicable Codes and Standards of National Fire Prevention Association (NFPA), USA, would also be followed. In view of vulnerability to fire and it's importance in the running of the power station, effective measures are to be taken to tackle fire in the following susceptible areas : i) The cable galleries, and ii) Coal handling areas, mainly the conveyors, transfer points and tunnels.

100 For containment of fire and preventing it from spreading to cable galleries, unit-wise fire barriers with self-closing fire resistant doors will be provided. The ventilation systems provided in the cable galleries, would be so interlocked with the fire alarm system that in the event of a fire the ventilation system is automatically switched off. Also to avoid spreading of fire, all cable entries/openings in cable galleries, tunnels, channels, floors, barriers etc. would be sealed with noninflammable/fire resistant sealing material. The source of water for the fire water pumps of the hydrant system, water spray and sprinkler system etc. will be the water with connection from cooling tower basin (to be used only during extreme emergency). Two(2) electric motor driven fire water pumps with one(1) diesel engine driven pump as back-up for sprinkler system will be provided in the fire water pump house. In addition to these, jockey pump sets, hydropneumatic tanks, compressors, pipes and fittings as required will be provided. The hydrant system will feed pressurised water to hydrant valves located throughout the plant and also at strategic locations within the power-house. Automatic high velocity sprinkler protection system will be provided for cable galleries, cable trenches/vaults, coal conveyors etc. Automatic medium velocity sprinklers will be used for protection of burner zone of boiler front. Automatic type water spray (emulsifier) protection system would be provided for the following equipment:- 5x800 MW-KSCTPP-FR-TANGEDCO -93- SEC - 5

101 a. Generator transformers b. Unit auxiliary transformers c. Unit and Station transformers d. Turbine oil storage tanks Suitable fire detection system as necessary for all the above mentioned fire fighting system with adequate supervisory circuitry will be provided. In addition to these, adequate number of portable and mobile (wheel mounted) chemical fire extinguishers of foam and soda acid type and carbon-dioxide type will be provided. Portable units would be placed at suitable locations throughout the plant area. The extinguishers may be used during the early stages of fire to prevent spreading. Fire station building of area (80mX25m) is provided for the power plant facility. FIRE DETECTION & ALARM SYSTEMS: A fire detection system as per National Fire Protection Association standards recommended practices shall be provided Manifestation of fire shall be sensed by the following methods: Photoelectric smoke detectors Multi sensor type smoke detectors Heat detectors (Rate of rise heat type or Fixed heat type). Both the type of detectors shall be addressable from the panel and operator interface. Infrared Ember Detector Non-electrically operated Fibre Optic type LHS Cable 5x800 MW-KSCTPP-FR-TANGEDCO -94- SEC - 5

102 Piping, Valves, Fittings & Specialties: The scheme of various systems such as, steam, condensate, water, oil, air etc. have been explained above. Piping, valves, fittings, hangers, anchors, supports, guides etc. would be provided as required. All high pressure, medium pressure and low pressure lines will be of proven quality and suitable for conditions of operation encountered at the specific points. Pipelines running outside the powerhouse will be routed over trestles as far as practicable in order to avoid maintenance and other problems encountered with trench piping and buried piping. However, for any culvert crossing piping inside trenches and for large diameter water lines buried pipes with proper coating and water-proofing would be adopted. Associated Facilities: Repair Workshop : The proposed station will have a well equipped workshop housing adequate machineries. Besides, instrument, electrical and maintenance shops are also envisaged. A repair shop for mobile equipment and motor vehicle repair shop would be developed. For heavy nature of maintenance, outside agencies are to be deployed. Work shop of area (150mX70m) is provided for the power plant facility. 5x800 MW-KSCTPP-FR-TANGEDCO -95- SEC - 5

103 General Stores : Both covered and open space as required for storage of various materials required for construction as well as operation and maintenance of the plant. While the construction stores will be temporary, the other stores will be permanent. Consumables, tools and tackle and other relevant items required for the project will be extended. Due to remote location of the plant, the stores would be well-equipped to handle any contingency situation. Accordingly, stores planning would be done for the project. Stores of area 100m X 75m with open yard 110m X 100m is provided for the power plant facility. The stores will broadly have the following divisions to house material of different categories: 1. Heavy materials store will house boiler tubes of various sizes, boiler and auxiliary parts, turbine heavy parts, stainless steel plates, conveyor belt and other coal handling equipment spares, dozer spares, motors, transformer windings, fire fighting equipment, insulators and hardware connectors, copper and aluminium conductors and similar heavy items. 2. Mechanical, electrical and instrument stores will accommodate small spare parts for mechanical and electrical equipment and instruments respectively. 3. Fast moving spares viz. electrodes and welding materials, blow lamps, bulbs and light fittings, grease, soap, battery, cotton waste and cloth, brooms, motor vehicle spares, gas 5x800 MW-KSCTPP-FR-TANGEDCO -96- SEC - 5

104 cylinders, gloves, aprons, safety belts, goggles, ropes, refill for the fire fighting equipment etc. will be stored in a separate godown. 4. Chemical stores will house alum, lime, morpholin/hydrazine resin, spirit and other chemicals required for steam, feed water and condensate system and chemical laboratory. 5. A civil engineering godown will accommodate cement, sanitary materials, filtering sand and filters, pipe and pipe fittings etc. for water supply. 6. Refractories and lubricants will be stored under separate covered sheds. Open storage-yard will be provided to store structural steel, plate materials, pipes, heavy castings, cable reels etc. Suitable enclosures will be provided for storing the insurance spares. Arrangements will be made for storing items like relays, motors, instruments under controlled atmospheric conditions. Condensate Polishing System: The proposed 5 x 800 MW project will be provided with 100% capacity condensate polishing system. Condensate polisher will comprise four(4) demineralisers per unit each operating in parallel. Any three(3) of these units will be capable of treating the full condensate flow at boiler MCR condition. Condensate polishing will ensure elimination of ammonia, silica, sodium or potassium from the condensate before being recycled to the 5x800 MW-KSCTPP-FR-TANGEDCO -97- SEC - 5

105 feed water system. During normal operation all the polisher units will remain standby. In case of high condensate conductivity, it will be pressed in service when three(3) of the exchanger vessels will be working in parallel and the fourth one will remain isolated from the system. The fourth vessel will act as standby and will be brought into operation when regeneration is required or during any emergency period. The polishing unit would be located at the powerhouse building. The operation of the condensate polishing system will be semi-automatic, remote/manual. The regeneration system will be external. For regeneration, the resins from the exhausted exchanger vessel will be transferred hydraulically to this facility located at DM plant and regenerated resin sent back in the same way. Chemical Laboratory & Testing Facilities: Plant will be provided with Chemical laboratory, C&I laboratory and Electrical laboratory with necessary test equipments, considered for the satisfactory and continued operation of power plant. A fully equipped chemical laboratory would be provided near the DM plant building. The testing and calibration laboratories for C&I and relay-metering will also be housed in the same building. Necessary equipment and standard instruments for chemical analysis of various items, testing of electrical items and testing/calibration of instruments would also be provided. Lab with an area of 35m X 20m is provided for the power plant facility. 5x800 MW-KSCTPP-FR-TANGEDCO -98- SEC - 5

106 Thermal Insulation: Adequate insulation will be provided to reduce heat losses from the equipment, piping and ducts and to ensure adequate personnel protection in critical areas. Insulation would be so selected that the covering jacket surface temperature does not exceed the surroundings ambient temperature by more than 15K (15 C). Pollution Monitoring System: Monitoring of various environmental aspects is of prime relevance in setting-up the proposed project. The following To keep watch on the state of pollution To generate data for predictive and corrective measures To quantify environmental impacts The important area requiring periodic/conditions monitoring aspects would be critically monitored:- are:- Stack emission Ambient air quality Disposed water quality, if any. Electronic smoke density analyser and gas analyser equipment is proposed to be provided for continuous monitoring of particulate matters at the outlet of ESP. Sample analysis of SO 2 and other pollutants from chimney would be carried out. Waste water would be checked for any harmful pollutants before discharging to outfall. An oil/water separation unit has been envisaged near fuel oil day tank/pump house area in order to keep plant drains free of 5x800 MW-KSCTPP-FR-TANGEDCO -99- SEC - 5

107 oil and to reclaim waste oil as far as practicable. Oil thus separated would be returned to the fuel oil tank after passing through plate settlers and used or disposed off by incineration. Coal Handling and Ash Handling Plants will be equipped with dust extraction/suppression system to combat fugitive dust. 5.5 Electrical System & Equipment Generation System & Power Evacuation: The Proposed power plant will have 5x800 MW at Kadaladi Taluk, Ramanathapuram Dist. in Tamilnadu with turbo generators rated at 27 kv level. These units will be connected to 765 kv GIS switchyard at the plant area as shown in the layout for evacuation of generated power. Also 230KV GIS switchyard is envisaged to receive start up power in case 765 KV system is not ready to supply start up power The total land area provided for the Switchyard is around 102 acres. In compliance with latest CEA Manual on Transmission Planning Criteria 2013, considering the large amount of power to be evacuated, power evacuation from the plant is envisaged at 765 kv level. In order to meet N-1 single contingency condition stipulated as per CEA planning criteria, minimum of two double circuit lines will be required to evacuate the net available power from the plant. Power from this switchyard would be evacuated through two (2) 765 kv double circuit lines to the nearest 765 kv pooling station, (location to be decided by TANTRANSCO the local STU). The Start-up power shall be received through station 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

108 switchyard connected to 765 kv grids. The power from grid shall be received through Generator Transformer (GT) and Unit Transformer (UT) to feed the station bus during start-up operation. The Generator circuit breaker is envisaged between Turbo generator and Generator Transformer. The bus bar configuration of the 765 kv GIS switchyard will be one and half circuit breaker arrangement as stipulated by CEA for better reliability. The following circuit bays are envisaged in 765 KV 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5 Switchyard:- Five (5) 765 kv circuits for generator transformers Two (2) 765 kv double circuits for outgoing lines Two (2) Spare bay (one equipped and another for future) Five (5) Shunt reactor bay (Qty to be decided during detailed engineering) Besides 765KV GIS, 230 KV GIS is also envisaged in order to meet the station start up power requirement in case 765 KV grid system is not ready to supply start up power. The station transformers shall be connected to 230 KV system. Double bus arrangement with buscoupler is envisaged for 230 KV system. The following circuit bays are envisaged in 230 KV GIS One (1) no Line in feeder One (1) no Line out feeder One (1) no Buscoupler Five (5) nos station transformer feeder One (1) no spare transformer feeder The rating and requirement of line reactors, shunt reactors and NGR for reactors will be provided in 765KV GIS as per system

109 studies requirement to be done during detailed engineering stage. A control room will be located in the switchyard premises to house switchyard control, metering and protective equipment. OFGW will be installed in the switchyard for reliable communication and carrier aided distance protection of 765 kv and 230KV system remote end breakers. In the powerhouse each generator will be directly coupled to the respective steam turbine. The generator will be a two-pole, three-phase unit rated for 800 MW at 0.85 p.f. lag. 50 Hz. The nominal voltage rating will be 27 kv or as per manufacturers standard with variation of ±10% in voltage, 50 Hz -5% +3%, 3-phase. The excitation system will be brushless type or static excitation (based on the proven practice of Generator OEM) and will be selected for an ideal rate of response, accuracy and sensitivity during normal as well as transient state of operation. The generator will be connected to the 765 kv GIS Switchyard through three numbers single phase 330/264/198 MVA, (765/ 3kV)/27 kv, generator transformer (GT). The GT shall be with OFAF/ONAF/ONAN type cooling and Vector group of YNd11. The total capacity of each GT will be thus (3x330) 990 MVA. The connection between GT low-voltage terminals to the generator will be done by isolated phase bus duct and high voltage terminals of GT will be connected to the switchyard bay through ACSR overhead conductors. The fault level of the switchyard 765 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

110 kv shall be 50 ka for 1 sec at 765 KV level and the switchyard shall have Main Bus I & II with 5000 Amps rating. The fault level of 230KV system shall be 40KA for 1 sec and the main bus1 and main bus 2 rating shall be 2000 Amps Power Supply Arrangement to the Unit & Station Auxiliaries: Three voltage levels viz V, 6600 V and 415 V have been envisaged to supply power to unit and station auxiliaries. The drives for auxiliary equipment, having capacity above 200 kw up to and including 1500 kw will be fed from 6.6 kv system and those with capacity above 1500 kw will be fed from 11 kv system. All motors rated 200 kw and lower will be fed from 415 V systems. Suitable HV and LV switchgears with suitable auxiliary transformers, as described below, will be provided for operation of these motors. Scheme of the electrical power distribution arrangement to the plant auxiliaries have been shown in Drawing No.15Z DWG-E-001 (3 Sheets). During normal power generating condition of generators, the power supply to unit auxiliaries will be fed from the generator terminal through Unit Transformer (UT) with GCB closed. During unit start up and when generator is not in operation the supply will be fed from the grid through Generator Transformer (GT) & Unit Transformer (UT) with GCB open condition. Two (2) nos. unit transformers have been envisaged per unit. Each UT will be directly connected to generator bus duct and will be rated for 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

111 40/32 MVA, 27 kv/11.5 kv and with OFAF/ONAN cooling, Dyn1 vector group. However the actual rating shall be decided during detail engineering. Power requirement for unit start-up or shutdown and station auxiliaries will be drawn from 765 kv Switchyard/Grid through Generator Transformer (GT) & Unit Transformers (UT). The station transformer (ST) will be provided with winding of adequate MVA and voltage ratings and Vector Group as Unit Transformer. ST will act as a standby back-up in case of UT fails. Also the start up power can be drawn from 230KV system in case 765 KV grid system is not ready. The power supply to unit auxiliaries like ID fan, FD fan, PA fan, BF pump, CW pump etc. will be from 11 kv Unit Switchgear fed by UT. Balance HV motors like Mill, CE pump, DMCW pump, IA/PA compressor etc. will be supplied from 6.6 kv Unit Switchgear fed by 11/6.6 kv, 16MVA Unit Auxiliary Transformer (UAT). (UAT rating shall be decided during detail engineering). The station auxiliary loads will be fed from 11 kv Station Switchgears located in the powerhouse. Separate 6.6 kv and 415 V switchgears will feed the loads for Coal Handling Plant, Ash Handling Plant, Water Treatment Plant etc., located in the respective plants as required. These 6.6 kv switchgears will be supplied by 11/6.6 kv Station Auxiliary Transformer (SAT) of suitable rating as required. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

112 The 11 kv sides of Unit Transformer (UT) and Station Transformer (ST) will be connected with the associated switchgears through adequately rated segregated-phase bus duct. The 11KV station switchgear is connected to the unit switchgear by the Tie feeder. The auto bus transfer scheme is envisaged (BTS system) for closure of tie feeder in case power supply failure on the unit board. OLTC panel is envisaged in the switchyard control room for remote operation of station transformer on load tap changer. The 6.6 kv side of Unit Auxiliary Transformer (UAT) & Station Auxiliary Transformer (SAT) will be connected with the associated switchgears through adequately rated segregatedphase bus duct. For PMCC/PCC switch board of 415 Volt system, 11 kv/415 Volts, 3-phase, 50 Hz, dry-type LV auxiliary transformers rated 2.5 MVA, 2 MVA, 1.6 MVA and 1MVA will be provided as required. The HV side of these transformers will be connected to 11 kv buses by cables and the LV side will be connected to the respective LV Switchgear/Power Control Centre (PCC)/Powercum-Motor Control Centre (PMCC) through non-segregated phase bus duct. The 11 kv system will be designed for 50kA fault level with short time rating 3 seconds & 6.6 kv systems will be designed for 40 ka fault level with short-time rating 1 second. The 415 V systems will be designed for 50 ka fault level with short-time rating 1 second. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

113 Emergency Power Supply System: 415 V emergency power supply system has been envisaged to provide power to essential auxiliary loads required to permit a safe shut down of the unit in the event of a plant blackout. In addition, emergency power will be provided for auxiliaries and services required for personnel safety and equipment safety during the blackout. In order to meet the above requirement Six (6) nos kva diesel generator sets will be installed, considering each DG sized for one unit and the Sixth DG set will act as common standby. The land area allocated for the DG house is around 15m X 10m. Plant DC System: 220 V Plant DC system has been envisaged for reliable power supply to those loads, which are required to function for security, protection and safe shutdown of plant in the event of failure of normal AC power supply. Each unit will have two (2) 220 V battery set of adequate capacity. DC power supply system for each unit comprises: 220 Volt DC batteries Battery charger (float and float-cum-boost charger) DC distribution and sub-distribution boards Battery will be Lead Acid PLANTE type or Nickel-Cadmium (Ni- Cd) type and the battery will be sized for one (1) hour back up time subsequent to tripping of generating units. Separate battery sets will be provided for 765 kv GIS switchyard, coal handling system, plant water system and AHP. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

114 Uninterrupted Power System: Two(2) sets of UPS systems of continuous duty have been envisaged to supply regulated, filtered and uninterrupted 240 V, 50 Hz, single phase power to critical AC loads like Instrumentation control system, PLC system during normal as well as emergency conditions. UPS battery will be sized for at least sixty(60) minutes back up on failure of normal AC supply. A separate UPS system of continuous duty has been envisaged for 765 kv GIS switchyard control room Substation Automation system, coal handling, ash handling and plant water system. Control of Electrical System: The Operation and Control of Electrical system/equipment have been envisaged from the Central Control Room through Operator work stations. Control and operation of 765 kv GIS switchyard will be done from switchyard control room. Accordingly, the 765 kv GIS switchyard will be provided with complete sub-station automation system with connectivity to plant DCS system. DG sets will be controlled from AMF panel in DG room. Remote control provision will also be provided in plant DCS. Control panels for service system like coal handling plant, ash handling plant, plant water system, etc. will be located in the respective control room. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

115 Protection & Metering System: The necessary protective relaying system based on state of art numerical technology according to established norms shall be provided for EHV switchyards, over head lines, generators, transformers, motors, auxiliary system etc., to minimize damage to equipment in case of fault and abnormal conditions. Numerical relays with 100% redundancy will be used for protection of critical electrical equipment and non critical electrical items the numerical relays with out redundancy shall be provided. Plant electrical parameters will be metered to the extent for proper operation and monitoring of plant conditions. Separate check meters and main meters will be provided in 765 kv and 230KV GIS switchyard line feeders for tariff metering of import and export power. Illumination System: Suitable illumination system will be provided to facilitate normal operation and maintenance activities and to ensure safety of working personnel. Required illumination levels in different areas will be as per standards/code of practice. Power supply for the illumination system will be derived from the following sources: Normal AC System to be powered from 415 V normal AC supply Emergency AC System to be powered from 415 V emergency DG set 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

116 Emergency DC System to be powered from 220 V plant DC system Illumination system will consist of lighting transformers, lighting distribution boards, indoor & outdoor type lighting panels, different types of lighting fixtures suitable for different plant areas, lighting cables & wires, etc. Intercommunication System: Two-channel voice communication system with Paging mode as well as Private mode has been envisaged for plant intercommunication. A microprocessor based Digital Electronic Private Automatic Branch Exchange (EPABX) is envisaged for the telephone communication system. Grounding & Lightning Protection System: Comprehensive grounding system will be provided in the power plant which will be achieved by ground mat buried at one (1) meter depth below ground and provided with ground electrodes at suitable intervals or as per IEEE80. All metallic parts of power plant and switchyard equipment/structures will be connected to the ground mat. Generator neutral will be grounded through distribution transformer and secondary loading resistor. 11 kv & 6.6 kv systems will be high resistance grounded to limit the fault current to the order of 300 Amp. 415 V power supply system will be solidly grounded. DC system will be ungrounded. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

117 For grounding of electronic equipment, a separate earthing system totally isolated from the power equipment earthing mesh will be provided. Lightning protection system will be installed for protecting the buildings/structures against lightning discharge. This would be achieved by providing lightning masts/shield wires on stacks, NDCT, powerhouse building, floodlight towers, towers in switchyard etc. and connecting them with the ground grid. Construction Power It is envisaged that about 10 MVA construction power may be required at 415V level when construction activities takes place simultaneously in all unit and station areas of the plant. TANGEDCO shall provide two single circuit 33 kv overhead lines from KADALADI 110KV/33KV SS up to construction site. At construction site suitable 33/11KV substation with 11KV/415V distribution network with transformers and Distribution board shall be provided to cater the construction power requirement. 5.6 Control & Instrumentation The Control and Instrumentation System envisaged for the project would be designed using microprocessor based state-ofthe-art technology with adequate redundancy to ensure Safe, efficient and reliable operation of the plant under all operating and plant load conditions for the entire plant life. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

118 Minimum human supervision and intervention in the plant operation. High Mean Time Between Failure (MTBF) and Low Mean Time To Repair (MTTR) of the Plant Equipment/System. Flexibility for ease of maintenance and plant operation and modular expansion capability. High degree of automation at all stages of operation. Diagnostic capability Control & Operational Philosophy: The Operation and Control of Main Plant Equipment of the project have been envisaged from the Central Control Room. One control room is envisaged for two units for centralised control and monitoring of unit equipments. a) One control room is envisaged for control and monitoring of Unit 1 & 2 to be located between Unit 1 & 2 b) Second control room shall be used for control and monitoring of unit 3 & 4 to be located between Unit 3 & 4 c) Third control room shall be used for control and monitoring of Unit 5 and common monitoring of CHP, AHP, Water treatment plant, etc to be located adjacent to Unit 5. A Distributed Control System (DCS) have been envisaged for the operation and control of Steam Generator (SG), Turbine Generator (TG) and its auxiliaries. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

119 Stand-alone Control System using Programmable Controllers (PC) have been envisaged for Coal Handling Plant, Ash Handling Plant (AHP), Pre-water Treatment Plant and DM Plant from the respective Local Control Rooms/Local Control Panels. Hardware interfaces shall be established with the DCS for remote monitoring of critical parameters. The overall control of the plant shall be carried out from three control centres and each are divided into following sub plant controls. a. All control activities involving steam generators, turbine generators, electrostatic precipitator and other associated equipment from unit control room (DCS based system). b. All control activities involving coal and ash handling plant, pre-water treatment plant, DM plant from local control room (PLC based system & interfaced with DCS system for remote monitoring). c. The control & monitoring of 765 kv switchyard shall be from Switchyard control room located near switchyard (SCADA based system). However monitoring of important parameters shall be provided in each Main plant control room. Main Plant & Equipment : Steam Generator (SG): The operation and control of the Steam Generator (SG) shall be achieved through Man-Machine Interface (MMI) Station from Central Control Room. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

120 The various controls such as Furnace Draught, Drum Level, HP Bypass, Superheater Temperature, Combustion Control etc. shall be performed through dedicated Controllers in the Distributed Control System (DCS). All sequential operations,controls & boiler protection trip for Boiler Auxiliaries viz. FD Fan/ID Fan/PA Fan, coal mills etc. have been envisaged through MMI Station and dedicated Controllers of DCS. Turbine Generator & its Auxiliaries: A separate and dedicated microprocessor based Control System have been envisaged for the protection of the Turbine and Control of the Turbine Governing Valves, Automatic Turbine Run-up, Turbine Stress Evaluator, Automatic Turbine Testing etc. All other Controls viz. LP Bypass, Lube Oil Pumps, Control Oil Pump etc. will be implemented in DCS. Turbine Supervisory System shall be provided along with suitable link to DCS for monitoring. All sequential operation, necessary interlock function and Auto/Manual operation of start/stop of the drives/ pumps shall be performed through MMI station of DCS. The start/stop operation and control of all other major equipment viz. Condenser, CEPs, LP Heaters, Deaerator, BFPs, HP Heaters etc. shall be achieved through the MMI Station. Control/sequential logic function and turbine trip shall be implemented in DCS. All major drives shall have local start/stop facility for testing purpose. BFPs shall be provided with local gauge board and vibration monitoring system. The operation 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

121 and control for the Common Auxiliaries of the station shall be achieved through dedicated Controllers and HMI in DCS. Functional Description of the Monitoring/Control System : General Technical Requirements : All equipment, system and accessories considered shall be from latest proven product range of established manufacturers and shall conform to applicable national and international standards. Adequate measures shall be taken into consideration to make the system fail safe such that loss of signal, loss of power supply or failure of any component will not lead to hazardous conditions as well as prevent occurrence of false trips. Distributed Control System (DCS) : A latest proven microprocessor based state-of-the-art Distributed Control System has been envisaged for the project. Control System shall be open architecture type to make the system user friendly. Adequate redundancies would be provided at all possible levels to achieve highest system availability. The proposed Distributed Control System shall comprise Functionally Distributed Controllers, Communication Processors, I/O Modules, Local Bus, Power Supply, etc. The task and duties to be performed are Sequential Control/Close Loop Control related to SG, TG and its auxiliaries. Acquisition of data and its validation 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

122 The sequence and interlock functions performed by DCS would be functionally arranged in groups/subgroups for auto operation Real Time Stamping for the inputs related to sequence of Event Recording MMIs and Controllers shall be connected by bi-directional high-speed redundant data hi-way Man-Machine Interface Station and its peripherals shall perform the following:- Operational facility for auxiliaries of SG, TG and balance of plant Displays like Mimic, Loop, Graphics Generation of Reports & Annunciation Performance and efficiency calculation Self-Diagnosis Fall back features of MMIs Interfacing with Large Video Screen (LVS) in Control room The system shall be provided with User friendly operating and application software. Dual Redundant Programmable Controllers (PC) for various offsite plants shall be provided. Steam & Water Analysis System (SWAS): SWAS shall be designed for continuous monitoring of Steam and Water quality at salient points of the cycle based on the 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

123 International Standards. functions. SWAS shall perform the following a. Sample handling to perform pressure and temperature conditioning of the sample to suit the analyzer probes. b. Analysis of ph, Conductivity, Dissolved Oxygen, Silica etc. at various points to monitor and control the steam and water quality at the desired level. c. Monitoring, recording, annunciation of various parameters shall be provided for remote DCS as well as for local SWAS Panel. All these SWAS related equipment would be housed in the SWAS Room. Continuous Emissions Monitoring System: Continuous Emissions Monitoring System has been envisaged to meet the statutory requirement. PC based Continuous Emissions Monitoring System shall be envisaged along with remote transmission facility through serial link. The particulate matter, SO²,NOx, Hg shall be monitored in Flue gas at stack as stipulated by MOEF Rotating Machinery Supervisory System: Vibration Monitoring System for major rotary equipment shall be provided as per the manufacturer s recommendation. These vibration and supervisory systems will be complete with sensors, junction box, special cables, transmitters, analysis system with monitors & communication capabilities with DCS. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

124 Field Instruments: Field Instruments shall be suitable for area in which these are located. In general, field instruments shall be weatherproof, dust tight and corrosion resistant. Field instruments shall be suitably grouped or clustered area-wise and shall be terminated in local junction boxes. Process Transmitters : All the Process Transmitters will be 2-wire SMART type. Process Gauges : Pressure Gauges (Bourdon/Bellows type), Temperature Gauges (Mercury filled-in type with SS armoured capillary/bimetallic), Level Gauges (Transparent and Reflex type) etc. shall be provided for local monitoring. Temperature Sensors : All Temperature Sensors will be Duplex type, bearing & winding temperature measurement shall be provided for HT drives as per the manufacturers recommendation. Process Switches : For critical alarm and protection/interlock functions direct process switch contacts will be used. Flow Elements : For the measurement of low-pressure flow for clean fluids, concentric square edge orifice plates shall be provided. Flow 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

125 Nozzles shall be provided for measurements to control for highpressure water/steam service. For fuel oil service, positive displacement/target-type flow-meters/vortex flowmeters shall be used. Aerofoils, annubars and venturies shall be used for airflow measurement. Final Control Elements : Generally pneumatic type Control Valves shall be provided except for critical functions where hydraulic type actuator shall be considered. Cable & Accessories : Necessary cables including prefabricated cables, data highway cable, instrumentation cable, compensating cable, control cable etc. shall be included. Generally cables will be overall screened, and with FRLS outer sheath. All interconnecting cables between cabinets will preferably be prefabricated with connectors at both ends. Panels & Cubicles : Operator s Console comprising workstations, CRTs would be provided in the each Central Control Room. The system cabinets containing hardware would be placed in the Control Equipment Room. Local panels would be provided for local monitoring and interfacing of Operators whenever needed. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

126 Erection Hardware : Erection hardware including all process connection and piping materials like impulse pipe, manifolds, fittings, pneumatic line tubes and pipes along with necessary fittings, junction boxes, cable accessories like glands, conduits, trays etc. shall be provided. Instrument Insulation Criteria : All instruments shall have clear access for maintenance, removal, lay down, calibration etc. All readable instruments shall be clearly visible unassisted. Access platforms shall be provided for easy access of instruments, valves and actuators for maintenance. Spares & Consumable: All electronic cabinets shall have installed spares to the extent of 10% to allow expansion and modifications. In addition, 20% spare capacity is to be provided in the form of rack space for augmentation & spares shall be judiciously distributed. All commissioning spares and consumable shall be supplied as part of main package. This is in addition to spare parts to be included for three (3) years of trouble-free operation. All failure-prone items shall be clearly identified and adequate spares are to be provided for such items. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

127 Tools & Tackle: All special tools and tackles shall be considered. Utility : In general, the electronic panels shall receive 240 V AC 1-Phase, 50 Hz at the desired locations. Two nos UPS adequately rated with 1 Hr battery back-up facility shall be provided for the critical systems. Separate instrumentation earthing shall be provided for protection of the system. Ambient Air Quality Monitoring system (AAQ): The comprehensive ambient air quality monitoring system with necessary sample collection system and probes shall be provided in the project area. The location of the monitoring station shall be decided taking into consideration the upwind direction, predominant downwind direction, habitation and other sensitive receptors. AAQ shall include PM10, PM2.5, SO², NOx, CO and Mercury measurement and recording. 5.7 Plant Layout The area identified for locating the grass root power station is spread over Ha of land and is located at a distance of nearly 65 km South-East of Ramanathapuram town. The plot has a ECR on the Southern and would be entrance of the road traffic to the station. The station conceived would be of 4000 MW capacity five units of 800 MW each deploying state-of-the-art 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

128 technology with conventional layout. The plant layout of the proposed thermal power station within the identified space is shown in Drawing No. 15Z DWG-M-003. This layout shows a single terrace plot plan. Thus when the contour survey will be available a multi-terrace layout will have to be developed. A conventional layout for the boiler and the turbine has been suggested for the power plant with the axis of the TG set transverse to that of boilers. As such, the plant is laid in East- West direction as per the shape of the plot. The turbine bay is followed by the heater bay, the electrical bay, the boiler proper with side mill bay configuration, electrostatic precipitators and lastly the chimney. The main plant area houses the turbine building, steam generator, 765 kv GIS switchyard, circulating water system, water treatment and DM plant, coal handling system with Railway siding and the ash disposal system. The disposition of the different elements has been decided on the basis of their functional inter-relations and the direction of incoming or outgoing materials. Unitised concept has been followed in the plant design as far as practicable. The unloading-cum-erection bays are considered at the beginning of the powerhouse building while the coal conveyor entry planned suitably for side mill configuration. Since the units would be implemented with a time gap of three (3) months in between, this will not cause any hindrance in construction of later units. The main power block with the 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

129 switchyard is located along the north south axis of the plot with the direction of evacuation to the south. Water treatment facility will be located on the south-east of the power block. It is proposed to deploy wet type Natural Draft Cooling Towers in the recirculating cooling water circuit. The cooling towers are located to the west of the powerhouse building with a designed gap, to optimise on length of C.W. piping. The coal yard along with other auxiliaries would be located on the north of the plot. Four pair of stacks of coal storage with handling facility have been planned at this location. The coal yard will be equipped with four stacker-cum-reclaimers. Coal stack lies in East-West direction. These would cater 30 days requirement of coal for the station. Three Track Hoppers have been envisaged for receiving rake loads of coal. Merry-go-round system is envisaged for the proposed project. However, details of coal transportation and unloading facilities would be finalised based on study reports. The power plant along with the area earmarked for auxiliaries and accessories would be located within the common security wall of the complex. The access road would enter the plant from the south, which is connected to the ECR. Another access for receiving material is shown at the north-eastern end and will lead to FGD material handling area, ash silos and fuel oil area. The Administrative Building (60m X 20m), for the entire complex is located at the entry to the plant and would have a boundary wall around with suitable entry. Service building (75m 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

130 X 75m) provided adjacent to the TG building All the senior executives of the power station will be located in this building. The entry to the Power Plant will be flanked by security gate, time office. It is proposed to construct one Crèche (24m X 11m), Dispensary(30m X 10m) and canteen (30m X 30m) facility. Provision of disposing fly ash by trucks from ash silos located on the western side of the plot is kept for gainful usages. The layout considers green verge as per MoEF norms. 5.8 Civil Engineering Aspects Plant Grading: The elevation of the selected site is about 6 m above MSL. This may be further worked upon when survey map of the plot is available and shall be duly addressed in DPR stage. Leveling and grading shall be carried out by selected cutting and filling of existing ground surface and earth. The cutting and filling requirements should balance each other to avoid earth from borrow pits as far as possible. Different grade levels may be adopted for different areas. Soil Characteristics & Foundations: The soil investigation of the plot is yet to be conducted. It was noticed during reconnaissance visit to the area, the top cover is composed of moorum followed by fragmented rock underneath. Detail soil investigation of the plot identified is necessary for 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

131 deciding on the type of foundation. For the purpose of the report, raft foundation with RC raft has been considered. Seismic Consideration: The power station area is located in Zone-II as per the demarcation of IS: of Indian Code of Practice. Analysis and design of structures would be carried out accordingly taking into consideration the factors related to soil characteristics and importance of the structure together with the basic seismic co-efficient as per provision of Indian Code. Wind Conditions: The maximum wind pressure including winds of short duration as specified in Indian Standard Code of Practice IS: (Part-3) will be adopted for the zone where the proposed power station is located. The site is located in the zone as per above standard having design wind speed of 40 m/sec. The provision of Indian Standard Code of Practice IS:875 with appropriate co-efficient for variation of heights and shape will be considered for detail design. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 5

132 6.1 Introduction ENVIRONMENTAL ASPECTS The selected plant site is encompassed by the villages Tharaikkudi, Kannirajapuram and Narippaiyur villages of Kadaladi Taluk, Ramanathapuram District. The site is around 2.3KM from sea coast line and at a distance of 65km from Ramanathapuram town. The area has typical tropical climate with hot summer and moderate winter. Supply of electricity is a basic need to support modern society and sustenance of economic and commercial activities. Imported coal from Indonesia any other country and Indigenous coal from Talcher, Odisha. Electricity generated in this power project would be transmitted to State Grid. Availability of quality power on sustained basis at a competitive price would be the main focus of the project. High investment in infrastructures together with availability of power in the area would attract other ancillary industries to be set up in the vicinity which in turn would have spin off effect on the community at large. Besides Kadaladi Talk in Ramanathapuram District is a very backward area and prone to communal disturbances, a power plant of this 5X800 Mw capacity will bring in lot of employment opportunities both direct and indirect and will pave away for communal harmony in this area. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

133 The effect of the proposed project on environment should be seen in the broader perspective of overall impact on the neighborhood. There are no archeological monuments within 25km radius of the proposed sites. The site does not include any forest land. Three Bird sanctuaries are located in the vicinity Melselvanur-Keelselvanur bird sanctuary at around 17 km, Chitrangudi bird sanctuary and Kanjirankulam bird sanctuary at around 22 km & 20 km respectively from the selected site (Site-B). The GOMNP (Gulf of Mannar National park) Vembar zone Uppu Tanni Tivu is around 11 km and Thoothukudi zone kariashuli Tivu is around 23 km from the selected project site. The site falls within the buffer area of the GOMBR (Gulf of Mannar Biosphere Reserve). Further assessment on environmental impacts and the requisite management plans shall be pointed out in a separate EIA/EMP study. The tentative location of intake and outfall is around 12 km and 19km away from the Uppu Tanni Tivu and Kariashuli Tivu in Gulf of Mannar. The location details are included in the Site Location Map of the proposed Thermal Power Plant Drawing No. 15Z DWG-M- 002 (sheet 2 of 2). Industrial growth is always associated with some effects on environment. Attempts will, however, be made both at macro level as well as micro level to minimise detrimental effect of the proposed project on the surrounding area. The proposed power station would be equipped with state-of-the-art pollution control devices to bring down the emission/discharge of pollutants within the acceptable norms of the country. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

134 It may be noted that the project area is vacant land without agriculture and free from R&R issues. As there is no habitation, no major eviction is involved. Project authorities would make adequate arrangement for rehabilitation and resettlement, if required as per the R&R norms laid down by the state government. Separate arrangement to address corporate social responsibilities (CSR) would be taken up by the project authority (For CSR activities the value considered is not less than 0.4% of the project cost). 6.2 Environmental Pollution from a Thermal Power Plant and Controlling Measures To evaluate the effect of the proposed project on the surrounding environment, various factors such as population distribution in the vicinity, type of land use, possibility of pollution from various sources etc. would be taken into consideration. Optimum blend of coal to reduce the consumption. Super Critical technology to have higher boiler efficiency and reduced GHG emission. Closed cooling water system with cooling towers envisaged, thus reducing significantly the makeup water requirement for the plant. Low NOx Burners and provision of Selected Catalytic Reduction (SCR) for NO X control ESP to minimize the PM emissions Stack of height 275 m to get better flue gas dispersion. Provision of FGD for SO X control 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

135 Feasibility Report Dust Control System to minimize the fugitive dust emission dust extraction / Dust suppression system in CHP. Provision of wind shield around coal stock yard It is proposed to use closed trucks for fly ash transportation in order to avoid dust nuisance. To reduce the dust nuisance while loading the ash into the trucks from fly ash and bottom ash silos, the ash is conditioned with water spray. Water sprinkling system to be envisaged in the ash disposal area and Gypsum disposal area to restrain flying of fine to atmosphere. A thermal power station utilising coal as its source of energy may pollute the environment in a number of ways. The major pollutants likely to affect the environment of the neighborhood 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6 are:- a. Suspended particulate matters (stack emission & material handling plant) b. Toxic gases viz. SO x, NO X (stack emission) c. Thermal pollution (stack, cooling tower etc.) d. Liquid effluent from plant services, power house drains, oil handling run off, run off from coal pile area, DM & CPU plant regeneration waste, Sea water clarifier sludge, Side stream filter backwash waste, ash pond run off and domestic waste. e. Noise generated during plant operation f. Dust emission in CHP and ash generated by burning fuel.

136 The various pollution control measures envisaged for the proposed project are as follows:- i) Emission from Stack Deployment of supercritical technology in the steam generator ensures lesser specific fuel consumption vis-à-vis generation of particulates, NO x and SO x compared to subcritical technology. Since ash content of the fuel is expected to be in the range of 26% (considering worst coal), a sizeable quantity of fly ash in the form of particulate matter would be generated. An efficient electrostatic precipitator will be provided to limit the emission of particulate matters to 30 mg/nm 3 (MOEF norm). The design would have provisions to augment and ensure lesser emission in the event of change of statute. High two twin-flue and one single flue stack are proposed to limit ground level concentration of SO x, NO x, etc. within acceptable limits by proper dispersion. With a properly designed furnace and burner system, generation of CO and NO x would be minimised. Heat loss through the stack is only about 8-10% of the total heat input to the furnace. This is nominal when compared with the capacity of earth as the heat sink and this would be adequately dispersed with the plume from the high stack. Moreover, majority of the heat in cooling tower is rejected in the form of evaporation loss. This does not cause any appreciable thermal pollution to the surrounding area. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

137 ii) Liquid Effluent from Water Treatment & Other Areas The heat cycle make-up water requirement under stabilized condition for the 5 X 800MW power station would be of the order of 125 m 3 /hr of demineralised water. The demineralising process would generate alternately acidic and basic effluents after regeneration of such type of exchangers. These effluents would be neutralised in a neutralising basin where proper neutralising arrangements for the effluent fluids would be provided. The neutralized effluent water would be discharged into the equalization basin termed as Guard Pond. In Drawing No.15Z DWG-M-009 waste-water generated from the plant and their treatment scheme are shown. In the recirculating cooling water system, the make-up water would be sea water. There will be blow down from the circulating cooling water system. This blowdown would largely be utilised in ash handling system. Sidestream filtration shall be envisaged to control the Total suspended solids (TSS) level at sea outfall in order to meet the MOEF norms. Other wastes from the processes include clarifier sludge & side stream filter backwash sludge waste which would be sent to sludge pond/pit and clean water as overflow would go to clear well and sludge would be pumped to ash pond. Other wastes from the processes like CPU regeneration would be neutralised in a neutralising basin where proper 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

138 neutralising arrangements for the effluent fluids would be provided. The neutralized effluent water would be discharged into the equalization basin termed as Guard Pond in Effluent treatment plant. AHP seal water system drains, waste from floor cleaning of plant area would be discharged into the Guard pond. In the power plant, some specific locations in turbine area and boiler area require washing, to maintain good plant housekeeping and prevent build up of dirt and waste material, which generate waste water. This waste water along with process drain will be led to an oil water separator for separation of oil. The clear water will be led to the Guard pond/central monitoring basin in Effluent treatment plant. The dirty oil will be recovered separately in a drum and sold to local users. The Guard Pond in Effluent treatment plant will act as an equalization basin for all treated/untreated liquid effluents. Provision will be there for use of this treated and equalized effluent partly in horticulture and green belt development. For the excess quantity, attempts will be made to attain zero waste water discharge through RO plant. The sewage will be collected from the Administrative building and canteen area, powerhouse area and fire station area. Sewage waste from the administrative building and canteen area will be collected by gravity into an oil grease trap. After the oil removal, sewage is collected in a bar screen chamber, where the floating 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

139 particles are removed from the sewage. From the bar screen chamber sewage is collected in a septic tank for anaerobic treatment. Sewage is then allowed to pass through an upflow filter. During the process, most of the COD, BOD and TSS in the sewage are removed. Overflow from upflow filters is collected in an oxidation pond where sodium hypochlorite solution is added for disinfection. Then treated effluent will be pumped for horticulture purposes. iii) Noise Emission Noise emission from equipment will have to be controlled at source. Adequate silencing equipment will be provided at various noise sources to attenuate the noise to acceptable level. Also plantation would be developed in plant area, which would help in reducing noise level to some extent. In Annexure-6.1, a list of basic equipment/instruments for environmental monitoring and testing for the proposed station is given. iv) Guard Pond It is envisaged to develop a guard pond to be located suitably in the low lying area of the plot for collecting the liquid wastes. The capacity of the pond would be adequate to store 24-hours design liquid effluent discharge from the station. Treated and equalized effluent from the Guard Pond will be treated in the effluent treatment plant by alkali/acid dozing and let off to be reused in horticulture and green belt development within the plant. Balance 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

140 treated effluent conforming to the norm will be discharged to the RO plant to achieve zero waste water discharged satisfying the requirement as stated in MOEF notification, Govt. of India. The storm water and catchment water which are not effluent from the plant would be drained by a separate drainage system. v) Green Belt Adequate green belt would be developed in and around the project area and the ash disposal area satisfying the requirement of state as well as Ministry of Environment and Forest (MOEF), Govt. of India. Plantation near coal stacks and the ash disposal area to arrest fugitive dust are also proposed. These green belts, apart from arresting air-borne dust particles and acting as noise-barrier, would help in improvement of ecology and aesthetics of the area. The area provided for Green belt is around 300 acres. vi) Rain Water Harvesting System Rain water harvesting system would be followed for the proposed project. In this scheme, roof water and surface water of the plant area would be collected through open storm water drain networks. The discharge outlet of these drain networks would be connected to a recharging pit from where water would be allowed to percolate into the ground. The basic purpose of this scheme is to assist the ground water table stability. Also, it is a compulsory scheme as per 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

141 the recommendations of the statutory/environmental bodies. vii) Solar Power Harvesting TANGEDCO proposes to harness solar power on the roof tops of main power plant building, switchyard control room building, water treatment building etc. The estimated area to be available for setting up solar power plant on above roof tops would be 3000 sq. m. Solar Technologies available are as follows : a. Solar photovoltaic cells b. Crystalline silicon c. Thin slim modules The quantum of solar power expected to be generated is in the order of kW. It is proposed to utilize solar power for control room lighting, switchyard area and switchyard control room lighting and water treatment/chemical analysis laboratory. Its integration with plant area electrical system would be examined at appropriate stage. Viii) DRY COOLING SYSTEM (Alternate option): Dry Cooling system is considered as an alternate option for the proposed project. Dry cooling systems are of two types Direct and Indirect. In direct dry cooling system, exhaust steam from LP turbine is directly cooled in a system of finned tubes by ambient 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

142 air. Mechanical draft to be used to move the air through fin tube heat exchange elements. To reduce pressure drop in steam conveying system, it needs to be installed close to the turbine hall. In an indirect dry cooling system, exhaust steam from the turbine is cooled by water in a condenser which can be of surface type, and hot water is cooled by air in finned tube bundles utilizing natural draft tower. The air cooled condenser units can be located away from the main plant. The cooling system shall be selected based on optimization of water requirement vis a vis plant efficiency. The type of cooling system shall be decided during detailed project preparation stage based on economic consideration. TABLE-6.1 COMPARATIVE DETAILS OF WET AND DRY COOLING SYSTEM Sl. N o PARAMETERS 1 Heat rate (Design Coal) kcal/kwh 2 Plant Water requirement (m 3 /hr) 3 Auxillary Power Consumption For single unit WET COOLING SYSTEM (NDCT) DRY COOLING SYSTEM MW (6%) 54.5 MW (6.8%) REMARKS Increase in differential rate by 7% Decrease by 80% 4 Area Foot print 15 acres 20 acres Note* 5 Project Capital Rs 26,165 Rs 28,782 cost excluding Crores Crores IDC 6 Cost per MW 7.70 Crores 8.47 Crores - - 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

143 In case of dry cooling system the Raw Water requirement for the plant shall be arranged from nearby desalination plant proposed at Kudhuraimozhi (TWAD Board). However, the adoption of dry cooling system will make the project economically unviable. IX) Flue Gas Desulphurization Plant (FGD) As per the sulphur content in coal as mentioned in Annexure-3.3 of the report, no flue gas desulphurization is necessary. However, as per guidelines of MoEF, the installation of FGD plant at the rear side of ESP or chimney is considered in the layout. The prescribed level for SOx is within 100 mg/nm 3 as specified in the latest MOEF notification. Wet FGD system is proposed for the project. In wet FGD system, limestone (CaCO 3 ) is used as reagent. Alternatively Dry FGD / Seawater FGD systems may be adopted. The FGD system shall be selected based on optimization of water requirement and plant efficiency and shall be decided during detail engineering stage. The performance / characteristics of different available FGD technologies are given in Table 6.1 below: The makeup water requirement for wet (limestone) FGD plant shall be met from desalinated product water. The tentative quantity of makeup water requirement for the proposed project is estimated at 1500m 3 /hr. The tentative quantity of limestone slurry preparation for the proposed 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

144 project is estimated at 120m 3 /hr. Limestone slurry preparation quantity (120m 3 /hr) is met from desalinated water (60m 3 /hr) and recycled water (60m 3 /hr) from FGD waste water treatment plant. The slurry/waste water generated in Wet FGD system shall be passed through hydrocyclone followed by a filtration plant to separate gypsum flakes and filtrate. The filtrate is recycled back to the FGD makeup system. Zero liquid discharge (ZLD) plant to treat waste water shall be envisaged (if required). The FGD system would require around 0.2 million tonnes of limestone per year. The generation of Gypsum is around 0.3 million tonnes per year. Closed storage area with storing capacity for 30 days is provided for the limestone and gypsum in FGD material handling area located at the eastern boundary of the plant. The total area provided for the FGD system is around 17 acres. In addition, an open storage area of 50 acres for the disposal of Gypsum is provided within the plan boundary near the ash dyke. 5x800 MW-KSCTPP-FR-TANGEDCO SEC - 6

145 RamanathapuramDistrict,Tamil Nadu Table 6.2 The performance / characteristics of FGDs DESCRIPTION UNIT WET FGD DRY FGD SEA-WATER FGD High Sulphur in Gas Economical. Most widely used Reagents used Limestone SO2 removal efficiency Power Consumption (% Power Plant % % Removal efficiency up to 98% Use 1 1.5% of electricity generated Not economical. Lime (Lime is more expensive than limestone) Removal efficiency up to 94% Use % of electricity generated, less than Wet FGD Not practical for high S coal (>1%S) Seawater Removal efficiency up to 90% Use % of electricity generated Capacity) Space requirement % Absorbent cost % Nil By-products Dry Calcium Sulphite, generation and Gypsum Calcium Sulphate Sulphate Ions disposal Mixture Utilized in Cement and Gypboard applications Disposal cost can be high. No by-products 5x800 MW-KUMTPP-FR-TANGEDCO SEC - 6

146 RamanathapuramDistrict,Tamil Nadu Commercial grade by-product Land-filling None. Discharge of Sea Water as per stipulated condition is critical. Impacts on marine environment need to be carefully examined (e.g., reduction of ph, inputs of remaining heavy metals, fly ash, temperature, sulfate, dissolved oxygen, and chemical oxygen demand). Investment cost Plant Capital cost 11 14% 9-12% 7-10% increase 5x800 MW-KUMTPP-FR-TANGEDCO SEC - 6

147 RamanathapuramDistrict,Tamil Nadu X) SCR (Selective Catalytic Reduction): SCR system is envisaged for the proposed system to control of NOx emission. The prescribed level for NOx is within 100 mg/nm 3 as specified in the latest MOEF notification. 6.3 Basic Information for Environmental Clearance: The background pollution level, in terms of SPM, SO x, and NO x etc. of the area is expected to be well within the prescribed limits of MOEF. Project authority will institute a separate study on Environmental Impact Assessment (EIA) to identify the effect of the project on the surrounding environment. The site does not include any forest land. Three Bird sanctuaries are located in the vicinity. Melselvanur-Keelselvanur bird sanctuary at around 17 km, Chitrangudi bird sanctuary and Kanjirankulam bird sanctuary at around 22 km & 20 km respectively from the selected site (Site-B). The GOMNP (Gulf of Mannar National park) Vembar zone Uppu Tanni Tivu is around 11 km and Thoothukudi zone Kariashuli Tivu is around 23 km from the selected project site. The site falls within the buffer area of the GOMBR (Gulf of Mannar Biosphere Reserve). Further assessment on environmental impacts and the requisite management plans shall be pointed out in EIA/EMP study. The tentative location of intake / outfall location is around 12 km 5x800 MW-KUMTPP-FR-TANGEDCO SEC - 6

148 RamanathapuramDistrict,Tamil Nadu and 19 km away from the GOMNP Uppu Tanni Tivu and Kariashuli Tivu respectively in Gulf of Mannar. As such the plot identified for the project does not involve any eviction and thus no rehabilitation would be necessary. Thus, no adverse economic impact is foreseen. As mentioned earlier, there would be no encroachment of any water body by the proposed project. The project also considers establishing all the major cost intensive items for pollution control viz. ESP, chimney, low NO x burner for furnaces, waste water treatment and recycling, afforestation etc. 6.4 Ash Management Plan A plot of 522 Acres has been identified for ash pond for dumping ash generated from the proposed project. Considering Bottom ash slurry disposal for 25 years and fly ash disposal of 1 st year-100%, 2 nd year-75%, 3 rd year 50% and 4 th year 25%. This area includes the peripheral road and statutory green belt around the disposal area. The Ministry of Environment & Forests notification dated 3 rd November, 2009, 100% fly ash utilisation from the complex need to be ensured within initial four years of operation. The ash generated can be gainfully utilized for filling, land filling of low lying areas located in closed vicinity and in cement plant. Possibility to minimize the requirement of ash dumping in the ash pond to be established. The high utilisation rate can be achieved by a comprehensive program for the standardization of by-products and active marketing of the by- 5x800 MW-KUMTPP-FR-TANGEDCO SEC - 6

149 RamanathapuramDistrict,Tamil Nadu products. Co-operation between the power plant and the Utilising Industry contributes to the high utilisation rate. 6.5 Gypsum Management Plan The successful environmental management strategy, which initiate the concept of sustainable development, is the maximum utilisation of the residue. Gypsum from a wet scrubbing system can be a substitute for natural gypsum. The areas of utilization of gypsum are in building materials for products like wall boards, plasterboards, mortars, cement etc. There should be a consideration of utilising the gypsum as close to the power plant as possible, which can be achieved by envisaging construction material production near power plant. Possibility of selling the gypsum for other uses would also be explored to minimize the requirement of dumping. The generation of Gypsum is around 0.3 million tonnes per year. Closed storage area with storing capacity for 30 days is provided for gypsum in FGD material handling area. An open storage area of 50 acres for the disposal of Gypsum is provided within the plan boundary near the ash dyke. 5x800 MW-KUMTPP-FR-TANGEDCO SEC - 6

150 SEA WATER ANALYSIS S.No. Parameters Value (ppm) 1. Total Solids 35, Dissolved solids 21, Suspended Solids Ignited residue 17, Volatiles Solids 4, Acid Insolubles Chlorides (as Cl) 20, Sulphates (as SO4) 1, Iron (as Fe) Total alkalinity (as CaCO3) Alkalinity due to Normal Carbonates (as CaCO3) Nil 12. Alkalinity due to bi-carbonates (as CaCO3) Total hardness (as CaCO3) 8, Permanent hardness (as CaCO3) 6, Temporary hardness (as CaCO3) 1, Calcium hardness (as CaCO3) 1, Magnesium hardness (as CaCO3) 6, PH 8.2 5x800 MW-KSCTPP-FR-TANGEDCO ANN 3.1

151 Ramanathapuram District, Tamil Nadu. Annexure 3.2 Sheet 1 of 2 Sl. No. Consumption Points 1. a. Heat Cycle Make-up b. Make-up Requirement for C.C.C.W System c. Chemical Feed System d. H2 Generation Plant e. Condensate polishing unit f. Regeneration of DM Plant e. Reject from BWRO ESTIMATION OF CONSUMPTIVE WATER REQUIREMENT Desalinated Product water usage (m 3 /hr) DM Water (m 3 /hr) Potable Water (m 3 /hr) Service water (m 3 /hr) Desalination feed water (m 3 /hr) Sub-Total (a to e) a. Potable Water Reqmt. for Plant b. Potable water Reqmt. For Township Sub-Total (a ) Sea water usage (m 3 /hr) CT Makeup water (m 3 /hr) Electrochlorination feed water (m 3 1% make-up Remarks 5x800 MW-KSCTPP-FR-TANGEDCO E/TH(P)/EE/E/KDI/F.DPR/P.O.NO.3/D.3/2016

152 3. a. Service Water b. AHP (Cooling & Sealing) c. ASH Conditioning d. HVAC plant makeup e. To Fire protection system f. FGD system makeup g. FGD Limestone slurry preparation h. CHP Dust Suppression Sub-Total (a to h) a Desalinated product water requirement (subtotals /hr 2265 m ) 3b Recycling of Permeate water from ETP RO plant 245 m3/hr 3c Total Desalinated product water requirement (sub-totals 3a 3b) 2020 m3/hr 4. a MLD Desalination plant reject water b. Ultra-filtration reject c. Clarifier sludge water d. Clear water recycled back from Sludge handling plant Feasibility Report Ramanathapuram District, Tamil Nadu. Annexure 3.2 Sheet 2 of m 3 /hr to CHP DS m 3 /hr recycled from FGD +45 m 3 /hr recycled from ETP Sub-Total 4 (a to c) - 4(d) + 3c CT Makeup water Side stream filters backwash sludge waste Electro-chlorination plant feed water 375 GRAND TOTAL (subtotals of ) Cusec With 5% margin Cusec Note: The above values are indicative and subject to change as per Bidder s requirement during detail engineering stage. 5x800 MW-KSCTPP-FR-TANGEDCO E/TH(P)/EE/E/KDI/F.DPR/P.O.NO.3/D.3/2016

153 ANALYSIS OF IMPORTED COAL (AS RECEIVED BASIS) PROXIMATE ANALYSIS COMPONENT (% BY WEIGHT) Moisture Volatile Matter Ash 6.62 Fixed Carbon Total ULTIMATE ANALYSIS Carbon Hydrogen 4.38 Nitrogen 1.48 Oxygen Sulphur 0.53 Ash 6.62 Moisture Carbonates - Phosphorous - Others - Total Gross Calorific Value Kcal/Kg HGI x800 MW-KSCTPP-FR-TANGEDCO ANN 3.3

154 ANALYSIS OF INDIGENOUS COAL (AS RECEIVED BASIS) PROXIMATE ANALYSIS COMPONENT (% BY WEIGHT) Moisture Volatile Matter Ash Fixed Carbon Total ULTIMATE ANALYSIS Carbon Hydrogen 2.60 Nitrogen 0.52 Oxygen 7.26 Sulphur 0.50 Ash Moisture Carbonates 0.38 Phosphorous 0.04 Others - Total Gross Calorific Value Kcal/Kg HGI 45 to 55 5x800 MW-KSCTPP-FR-TANGEDCO ANN 3.3

155 Ramanathapuram District, Tamil Nadu Annexure 4.1 Sheet 1 of 3 SITE-A Location : Kadaladi, Ramanathapuram District Connectivity to Site : The site is 5km from Sevalpatti-Tharakudi district road Water Source : Gulf of Mannar Grid Connectivity : TANTRANSCO Coal Connectivity : From Thoothukudi port by Rail S.no Name of the Village Poromboke Land in Ha Proposed Area Patta Land in Ha Dry Wet Total Area in Ha 1. Kondanallampatti T O T A L : This site was not considered further for: 1. The intake corridor over land to be taken along site-2 and the distance works out to around 10km. 2. The site has maximum agricultural land. 3. The site has few habitats which are likely to cause R&R issues. 5x800 MW-KSCTPP-FR-TANGEDCO E/TH(P)/EE/E/KDI/F.DPR/P.O.NO.3/D.3/2016

156 Ramanathapuram District, Tamil Nadu Location : Kadaladi, Ramanathapuram District Connectivity to Site : By Road, 1 Km from East Coast Road Water Source : Gulf of Mannar Grid Connectivity : TANTRANSCO Coal Connectivity : From Thoothukudi port by Rail S.no Name of the Village Poromboke Land in Ha Annexure 4.1 Sheet 2 of 3 SITE-B Proposed Area Patta Land in Ha Dry Wet Total Area in Ha 1. Tharaikudi Kannirajapuram Narippaiyur T O T A L : This site has been considered as best suitable due to: 1. Project area is spread over 3 villages and the orientation is compact in nature. mostly barren partly with patches of bushes and palm trees. 2. Availability of adequate vacant land without agriculture and free from R&R issues.the orientation is compact in nature 3. As the site is near to sea shore (i.e) about 2.3 Km, the requirements for plant water system could be easily met out. However, it is also reasonably away from the sea coast in compliance with CRZ. 4. The site is near the proposed alignment of B.G. Railway line from Kanyakumari to Karaikudi and hence it will facilitate transport of coal from Tuticorin port to site. 5. The site is nearer to the existing East coast road 6. The project site and the intake / outfall location is 11km & 12km away from the Uppu Thanni Thivu Island in Gulf of Mannar. The tentative corridor route and land fall point is indicated in the DRG. 15ZO3-004-DWG-M-003, the tentative area for the corridor is around 12 acres. 5x800 MW-KSCTPP-FR-TANGEDCO E/TH(P)/EE/E/KDI/F.DPR/P.O.NO.3/D.3/2016

157 Ramanathapuram District, Tamil Nadu Location : Kadaladi, Ramanathapuram District Connectivity to Site : The site is around 2km from ECR Water Source : Gulf of Mannar Grid Connectivity : TANTRANSCO Coal Connectivity : From Thoothukudi port by Rail Annexure 4.1 Sheet 3 of 3 SITE-C S.no Name of the Village Poromboke Land in Ha Proposed Area Patta Land in Ha Dry Wet Total Area in Ha 1. Valinokkam Siraikkulam T O T A L : This site was not considered for: 1. The project site and the intake is 5.5km from the GOMNP Keelakarai zone. 2. The Intake/outfall location with respect to the site location will be in close proximity with the GOMNP. 3. The project site southern part overlaps with 500m HTL. 4. The site has some agricultural land and habitat which may cause R&R issues. 5x800 MW-KSCTPP-FR-TANGEDCO E/TH(P)/EE/E/KDI/F.DPR/P.O.NO.3/D.3/2016

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