Chlorine Alkali Plant Uzboy, Balkanabat, Turkmenistan Environmental Assessment February 2010

Transcription

1 Chlorine Alkali Plant Uzboy, Balkanabat, Turkmenistan Ensacon GmbH - HSE Management Pierstr. 1 D Köln Tel Fax schaaf@ensacon.com

2 Contents 1 Introduction Project scope Formal requirements Methodology Legal requirements and technical standards Project description Project location and surroundings Project location Geology Climate People and economy Vicinity of the project area Protected areas General Arrangement of the Plant General process principles Process description Unit 01: Salt Dissolving Unit 02: Brine Treatment Unit 03: Brine Storage Unit 04: Membrane Electrolysation Unit 05: Anolyte Section Unit 06: Chlorine Drying Unit 07: Chlorine Compression Unit 08: Chlorine Liquefaction, Storage and Loading Unit 09: Catholyte Section Unit 10: Chlorine Absorption and Hypochlorite Production Unit 11: Caustic Soda Evaporation and Flaking Unit 12: HCl Synthesis Unit 16: Utilities Unit 19: Tank Farm and Loading Process control Emissions, effluents, discharges Air Emissions Emission sources Environmental noise Water demand and wastewater discharge Water demand Wastewater Spillage to surface water, groundwater and soil Waste management EA Chlorine Uzboy FEB 2010.doc FEB

3 4 Project alternatives Alternative processes Alternative locations Impacts of the project Air quality Method of assessment Baseline conditions and project impact Environmental noise Water demand and wastewater discharge Spillage to surface water, groundwater and soil Waste management Infrastructural impacts Nature and landscape conservation Process safety Inventory of hazardous substances Safety equipment and measures of protection General safety hazards Site Layout and Spacing Design of equipment Safety functions by process control systems Pressure relief systems Emergency shut down system Emergency absorption system Explosion protection Monitoring, Alarm and Communication Systems Fire protection Hazard Identification and Risk Assessment Process risks External risks Natural hazards Hazards from action by unauthorised persons Consequence analyses Chlorine release from piping Chlorine release from storage Occupational health impacts Number of workers Hazardous substances Workplace noise Impacts during construction EA Chlorine Uzboy FEB 2010.doc FEB

4 9 Health, Safety and Environment Management HSE Management System Annex 1 - Stack height calculations Annex 2 - Hazardous substances data sheets EA Chlorine Uzboy FEB 2010.doc FEB

5 Revision overview Rev. 0 First issue 2. EA Chlorine Uzboy FEB 2010.doc FEB

6 Executive Summary Project scope: Turkmenchimia is planning to construct and operate a Chlorine Alkali Plant at the site of their existing site at Uzboy, Balkan Province, Turkmenistan. Production capacity is t/a NaOH, t/a liquid chlorine, t/a of 32 wt-% HCl, and 3000 t/a of sodium hypochlorite solution. A membrane type electrolysis process will be applied with NaCl as feedstock. Electricity and steam will be supplied by a gas turbine that is part of the scope. The distance to the closest housing area is 1100 m. Air pollution control: The membrane unit as such has not relevant emission sources. Smaller streams containing HCl, NaOCl or chlorine are routed to an absorber. The only relevant emission source is the gas turbine with approx. 20 kg/h NOx. The emission is controlled by primary measures, i.e. state-of-the-art low Nox combustion turbine. Clean natural gas is used as fuel, i.e. no other relevant components in the offgas have to be considered. The resulting ground level concentration were calculated and are irrelevant according to internal standards. No further measures are required. Noise control: The plant will be designed for 70 db(a) at battery limit. The expected incremental sound pressure level at the next housing area is expected to be 38 db(a) and thus more than 6 db(a) lower than the relevant World Bank standard for residential areas. The additional noise will thus be irrelevant. Special additional noise reduction measures are not required. Water and wastewater management: The plant's water demand of approx. 45 m³/h is covered by process water via a new supply pipeline. The wastewater contains only mineral salts and is routed to an evaporation pit close to the plant. Due to the fact that the whole area is characterised by salty marshes this practice is acceptable. Details should be further clarified during the engineering. Soil and ground water pollution control: All relevant process and tankage areas where liquids are handled are designed according to international best practice with regard to surface design, drainage and retention volumes. Further control measures are not required. Waste management: The most relevant process residue are residual mineral salts and sludges especially from the NaCl dissolving and brine treatment process with a total quantity of approx t/a. This residue does not contain hazardous components and can managed without specific precautions. The actual ways of disposal for all waste streams still have to be clarified during further engineering. Safety: The plant is safety relevant according to international process safety regulations such as EU Seveso II directive due to its inventory of chlorine and sodium hypochlorite (150 t each). The design of the plant will follow international safety standards for chlorine plants - especially the standards set forth by the Russian Chlorine Safety Authority. Consequence analyses have been performed; the results show that the given safety distance to the next housing area (1100 m) is adequate. 2. EA Chlorine Uzboy FEB 2010.doc FEB

7 1 Introduction 1.1 Project scope Turkmenchimia is planning to construct and operate a Chlorine Alkali Plant at the site of their existing iodine plant at Uzboy, Balkan Province, Turkmenistan. The feed is solid sodium chloride (NaCl) from the Turkmenbashi area. The plant is designed to produce t/a sodium hydroxide (NaOH) t/a chlorine mainly as an intermediate product. The produced gaseous chlorine will be further processed to the following products: t/a liquefied chlorine t/a of hydrochloric acid with 32 wt-% HCl t/a sodium hypochlorite (NaOCl) solution with an active chlorine content of 170 g/l. The plant is a grassroot facility - the existing facilities will only be used to a very limited extent. The project comprises - apart from the production facility within battery limits - a connecting natural gas pipeline and a connecting process water pipeline to provide the energy and utility supply of the plant. 1.2 Formal requirements The is a formal document provided by the project sponsor and preferably prepared by an independent consultant, which summarises the process and results of the environmental analysis of a project having the potential for significant and diverse impacts. Environmental impact assessment is the process of evaluating the environmental impacts of a project and identifying ways to improve the project environmentally by preventing, minimizing, mitigating, or compensating for adverse impacts. The principal procedure in drawing up an are documented in the Sourcebook by the World Bank 2. EA Chlorine Uzboy FEB 2010.doc FEB

8 1.3 Methodology There are the following main steps in environmental assessment: Analysis of the process and identification of potential impacts Analysis of the receiving environment (base line study) Prediction of the impact of the project on the receiving environment Ranking the significance of these impacts and making recommendations for mitigation of the impacts 1.4 Legal requirements and technical standards Turkmenistan laws with relevance for the environmental aspects of the project are: Law on nature protection (1991) Об охране природы Law on state expert reports (1995) О государственной экологической экспертизе Law on the protection of the atmospheric air (1996) Об охране атмосферного воздуха Law on state nature protection areas (1992) О государственных особо охраняемых природных территориях Law on protection and utilisation of flora (1993) Об охране и рациональном использовании растительного мира Sanitary Code of Turkmenistan (1992) Санитарный Кодекс Туркменистана In addition to the environmental legislation the project also has to comply with construction laws and standards of Turkmenistan. The Turkmen environmental laws do not imply technically specific regulations and requirements for this type of project. For this reason international technical standards are applied such as: Russian Chlorine Safety Authority: Safety requirements for production, storage, transport and utilisation of chlorine - PB EA Chlorine Uzboy FEB 2010.doc FEB

9 German First General Administrative Regulation Pertaining the Federal Immission Control Act (TA Luft), 2002 EU COUNCIL DIRECTIVE 96/82/EC (1996) on the control of major-accident hazards involving dangerous substances (Seveso II directive) EU COUNCIL DIRECTIVE 2001/80/EC (2001) on the limitation of emissions from certain pollutants into the air from large combustion plants 2. EA Chlorine Uzboy FEB 2010.doc FEB

10 2 Project description 2.1 Project location and surroundings Project location Turkmenistan Project location The project is located in Uzboy approx. 26 km southwest of Balkanabat in the western Balkan Province of Turkmenistan. Geographically the project area belongs to the Turkmen Karakum desert. The Karakum is approximately 350,000 km² in area, extending some 800 km from west to east and 500 km from north to south. 2. EA Chlorine Uzboy FEB 2010.doc FEB

11 Karakum desert close to the project location The plain of the Central Karakum runs from the Amu Darya to the Caspian Sea. The height of wind-accumulated, halfovergrown sand ridges ranges from 75 to 90 m, depending on age and wind velocity. Somewhat less than 10 percent of the area consists of barchans (crescentshaped dunes), some of them 10 m or more in height. There are numerous interdune depressions (takyr), which are covered by clay deposits up to 10 m thick and act as catchment basins for the region s scanty precipitation; the water collected in these basins makes it possible to grow such fruits as melons and grapes. Saline areas (solonchaks) are also formed by the evaporation of subsoil water. The project location is in the utmost west of the Central Karakorum, approx. 50 km from the Caspian Sea. It is situated close to the former river Uzboy, which was a distributary of the Amu Darya and flowed through the northwestern part of the Karakum to the Caspian Sea until the 18th century, when it abruptly dried up. The former river is marked today by a chain of mainly salt water lakes. The elevation of the site is approximately 0 m, i.e. 28 m above the Caspian Sea level. Balkan mountains close to Balkanabat Geology Some 30 million years ago the entire Karakum region was covered by the sea. Orogenic (mountain-building) processes in the southern part of the Turan Plain resulted in a gradual diminishing of the sea and, ultimately, in its disappearance. Subsequently, the Amu Darya flowed across the Karakum, changing its bed from time to time and depositing large amounts of alluvial sediments (mostly sand and clay). The Karakum sands now contain some 40 different minerals brought down from the mountains to the southeast. After the Amu Darya changed its course and turned to the north to drain into the Aral Sea, the surface of the Karakum came to be shaped largely by eolian processes, which account for the present diversity of the desert s landforms. The subsoil at the location of the plant consist of sand layers with a thickness of 8 m or more. 2. EA Chlorine Uzboy FEB 2010.doc FEB

12 2.1.3 Climate The climate of the Karakum is continental, with long, hot, dry summers and unpredictable but relatively warm winters. The climatic situation at Uzboy is characterised by the following data: average temperature January: 0.0 C average temperature July: 31.1 C absolute lowest temperature: -28 C absolute highest temperature: 38.1 C total precipitation: 224 mm daily maximum precipitation: 72 mm average snow coverage: days/a average sandstorm frequency: 30 days/a predominant wind: January, direction/speed E (50 %), 3.6 m/s July, direction/speed W (44 %) 4.0 m/s People and economy The population density of the Balkan Province is approx. 3 persons per square kilometre and thus is the lowest in Turkmenistan. From antiquity the inhabitants of the Karakum practiced nomadic pastoralism and fished along the shores of the Caspian Sea and the Amu Darya, but in modern times nearly all have settled onto collective and private farms and have developed permanent towns with gas and electricity. Cattle-raising teams care for the livestock. The development of oil, gas, and other industries has brought new settlements. Traditionally, the inhabitants of the Karakum dug deep wells and used catchment areas to collect rainwater. Modern irrigation - especially the Karakum Canal - has made some areas of the desert suitable for raising livestock on a large scale, however not in the project area. There is no relevant agricultural activity. Intensive economic development after World War II has brought an industrial revolution to the Karakum. Factories, oil and gas pipelines, railroads, and highways, as well as thermal and hydroelectric power stations, have changed the face of the region. A number of natural resources also have been exploited, including sulfur, mineral salts, and building materials. The Balkan Province has significant energy reserves, which account for most of Turkmenistan's natural gas production and a significant share of its petroleum production. 2. EA Chlorine Uzboy FEB 2010.doc FEB

13 Project location Balkanabat - 26 km from the project site - is the capital city of Balkan Province, at the southern foot of the Great Balkan Ridge. Its former name, Nebitdag, means Oil Mountain, and it is the headquarters of the Turkmen oil industry. Balkanabat grew up on the Transcaspian Railway after large oil deposits had been discovered in the area in the early 1930s; it became a city in It has been carefully planned, with much greenery to mitigate the effects of the surrounding desert. The population is approx Vicinity of the project area The project area is part of an existing industrial site that has partly been abandoned. The overall area of this site is approx. 600 x 400 m. The southern part is occupied by an iodine plant. The project area for the chlorine alkaline plant is the northern section of the site. The vicinity of the site is characterised mainly by the desert and salty marshes with oil and gas production facilities north and west of Uzboy and the village of Uzboy to the north west. Uzboy is a small village with some 30 houses at a distance of 1100 m from the project site. Apart from Uzboy there are no other housing facilities in the surrounding area of the site. 2. EA Chlorine Uzboy FEB 2010.doc FEB

14 Besides the road and the railway line to Balkanabat there is no relevant infrastructural facility in the neighbourhood of the project site. Uzboy 1100 m chlorine alkali plant Project location - aerial view Protected areas There are no protected areas in the relevant vicinity of the project site. 2. EA Chlorine Uzboy FEB 2010.doc FEB

15 2.2 General Arrangement of the Plant The chlorine alkali plant is located at the north of the existing Uzboy industrial site. The area of the plant is about 200 x 150 m. The electrolysis unit is arranged inside a building (approx. 70 x 20 m) at the centre. The general arrangement of the plant is shown by a layout plan and an isometric view on the next page. 2.3 General process principles In the NaCl electrolysis section, sodium hydroxide, chlorine and hydrogen are produced from a saturated sodium chloride solution. The process can be represented as follows: 2 NaCl + 2 H 2O kwh Cl 2 + H NaOH NaOH and hydrogen are formed on the cathode, chlorine on the anode. The membrane electrolyser comprises an assembly of alternating anode and cathode plates. An impermeable ion-conducting membrane is sandwiched in between each successive pair of anode/cathode plates. The membrane consists of a perfluorinated polyethylene parent structure, the side chains of which contain sulphuric acid and carboxylic acid groups. The membrane cell consists of one cathode and one anode chamber that are separated by the membrane. The anode plate in the anode chamber consists of activated titanium. The cathode plate in the cathode chamber consists of a nickel alloy. 2. EA Chlorine Uzboy FEB 2010.doc FEB

16 200 m fire water chlorine rail car loading fire brigade HCl storage salt storage store workshop NaOH flaking NaOH storage chemicals storage NaOCl storage salt dissolving parking brine basin electrolysis filtration gas turbine HCl synthesis H2SO4 storage liq. Cl 2 storage demin water unit administration wastewater res. Cl2 container storage cooling water raw water supply 2. EA Chlorine Uzboy FEB 2010.doc FEB

17 Cl2 + - H2 Anolyte Separator Catholyte Separator Electrolyzer HCl Demi. Water Brine Depleted Brine CW Catholyte Cooler NaOH Depleted Brine tank Caustic Soda Tank Depleted Brine Pump Caustic Soda Pump Process flow of anolyte and catholyte circulation A concentrated sodium chloride solution is fed into the anode chamber. On the anode, chloride ions are discharged and form chlorine gas. Brine depleted of NaCl leaves the anode chamber. Na + ions permeate through the membrane to the cathode compartment. In the cathode compartment water is cathodically reduced to hydrogen and hydroxyl ions. The hydroxyl ions together with the sodium ions that have permeated through the membrane form sodium hydroxide. 2.4 Process description Unit 01: Salt Dissolving Dry NaCl is delivered by truck and or railway to the plant site and stored in an open concrete storage area with a capacity of about 450 t. By means of a tractor shovel the dry salt is continuously transferred to the salt dissolver. The salt dissolver consists of two dissolver basins with a common overflow to the pump pit of the raw brine pumps. One salt dissolving basin is operating, while the second is being cleaned or is at stand-by. Depleted brine from the electrolysis is fed to the dissolver basin at a concentration of approx EA Chlorine Uzboy FEB 2010.doc FEB

18 g/l. From the dissolver basin raw brine at a concentration of approx. 305 g/l flows over to the raw brine pumps and is pumped to the brine treatment unit. Most of the insoluble constituents of the salt are retained at the bottom of the salt dissolving basin and must be removed discontinuously by manual action or by crane. The remaining sludge is filled into containers and stored at the waste storage area before shipment by trucks (solid waste R-01) Unit 02: Brine Treatment Brine primary treatment Primary brine purification serves for eliminating soluble impurities by precipitation. Sulphates are precipitated by BaCO 3 to form BaSO 4, calcium is precipitated by Na 2CO 3 to form CaCO 3 and magnesium and iron are precipitated with NaOH as hydroxides. The chemicals are mixed with the raw brine in precipitating tanks and the mixture flows into two mixing tanks. To promote flocculation and the filtration process, a flocculant is added after the second mixing tank. From there the brine flows into a clarifier where the brine remains a certain time and the impurities settle down to the bottom. The clarified overflow from the clarifier is routed to the secondary brine purification, while the concentrated solid sludge is withdrawn at the bottom of the clarifier and further concentrated in the downstream chamber filter presses. The resultant concentrated sludge is filled into containers for disposal (solid waste R-02), while the filtrate is routed to the following brine filtration. Brine filtration In the following pre-coat filtration process, the brine is mixed with a filter aid (in most cases alpha cellulose). The filter cake that is formed as a result on the filter cartridges retains the solid matter. When a preset differential pressure or a preset brine quantity is reached, the cartridges are cleaned by back-flushing with air. The sludge is withdrawn to a sludge container (solid waste R-02). From time to time, the filter candles have to be cleaned with diluted hydrochloric acid. The regenerate obtained from the regeneration of the filters is collected in a regenerate collecting tank. The regenerate is recycled to the dissolving unit. The filtered brine flows into the filtered brine tank and is then pumped to the ion-exchanger unit for further purification. Ion exchanger 2. EA Chlorine Uzboy FEB 2010.doc FEB

19 To achieve a final Ca/Mg content of approx. 20 ppb according to the requirements of the electrolyses the brine is further purified by an ion exchanger unit. By passing through the exchanger resin Ca and Mg ions are exchanged with H + ions. The adsorbers are regenerated discontinuously, the regeneration sequence is fully automatic. There are three parallel exchangers, two of them always on-line. For regeneration of the ion exchanger resins diluted hydrochloric acid is used, followed by diluted NaOH solution for conditioning. Demineralised water is needed for the dilution of hydrochloric acid and NaOH as well as for flushing the resin bed. The acid regeneration liquid is neutralised with NaOH and routed to the wastewater system (wastewater W-01). The NaOH used for final flushing of the regenerator is recycled to the dissolving unit Unit 03: Brine Storage The pure brine discharged from the ion exchanger unit is routed to the pure brine tank for intermediate storage. The buffer volume is 80 m³ allowing for 4 h of production in case of any failure of upstream units. From the tank the pure brine is pumped to the electrolyser. To maintain a brine temperature of C a heat exchanger is arranged at the tank outlet and a sidestream is routed back to the tank Unit 04: Membrane Electrolysation The unit consists of two parallel electrolysers. Each electrolyser consists of 48 cells, a catholyte circulation system (tanks, pumps and heat exchangers), an anolyte circulation system (tanks and pumps), associated piping and instrumentation, and a DC power supply (transformer/rectifier with bus bar system). The electrolyser cells are arranged at an elevated level. The anolyte and catholyte systems including tanks, pumps and heat exchangers are arranged at ground level to collect the depleted brine and caustic product from the electrolysers by gravity. Piping header systems supply the feeds and collect the products and by-products to and from each electrolyser. Each electrolyser has six process fluids/gases: two feeds and four product/by-products. The feed to the anode section of the electrolysers is brine, the products are depleted brine and chlorine gas. The feed to the cathode section of the electrolysers is recycled sodium hydroxide solution, while the products are sodium hydroxide solution and hydrogen gas. 2. EA Chlorine Uzboy FEB 2010.doc FEB

20 Electrolyser A bipolar cell frame consists of an anolyte compartment and catholyte compartment separated by a membrane. The anolyte compartment is made of titanium to give resistance against chlorine. The catholyte compartment is made of nickel. Ribs on which the anode and the cathode are welded are fixed on each side of pan by welding. Each compartment has two nozzles for inlet and outlet of electrolyte and one gas separator chamber at the top of it. The membrane and the electrodes have to be replaced after some time of operation (solid waste R-03/05). Electrolyser Unit cell 05: Anolyte Section 2. EA Chlorine Uzboy FEB 2010.doc FEB

21 The purified brine is supplied to the anolyte inlet sub-header of each electrolyser by the purified brine pump under flow control. Hydrochloric acid is continuously added to neutralize OH- ions, which migrate through the membrane from the catholyte compartments. The purified brine is then electrolysed in the anolyte compartments, while chlorine gas is generated and the sodium chloride concentration is decreased. The mixture of chlorine gas and depleted brine is discharged through flexible hoses via the outlet sub-header to the anolyte separator. Chlorine gas separated in each anolyte separator is collected in main chlorine gas pipes and sent to the chlorine gas treatment section under pressure control. Depleted brine from the separator is collected into the anolyte tank. Part of the depleted brine is directly routed back to the purified brine feed and the rest is recycled to the dissolver unit via chlorate elimination and dechlorination. Chlorate elimination Membrane electrolysers form some hypochlorite in the discharged anolyte as a side reaction, which then reacts to chlorate: 2 NaOH + Cl 2 NaOCl + NaCl + H 2O 3 NaOCl NaClO NaCl To eliminate chlorate from the anolyte cycle a side stream is sent to the chlorate decomposer and acidified with hydrochloric acid, where the chlorate is decomposed according to the following equation: NaClO HCl NaCl + 2 Cl H 2O Anolyte dechlorination The outlet of the decomposer is remixed with main anolyte stream. With a resulting ph of 1.7 to 2.0 residual chlorine is removed from the anolyte by applying vacuum. The vacuum is generated by a vacuum pump. The chlorine gas discharged from the vacuum pump is normally routed to the chlorine product line. The brine leaving the vacuum dechlorination tank still contains about 20 ppm of chlorine. To further remove chlorine Na 2SO 3 solution is dosed to the brine in a next step: Cl 2 + Na 2SO 3 + H 2O Na 2SO HCl Finally, anolyte with less than 0.1 % of chlorine is returned to the salt dissolving basins. Chlorine cooling 2. EA Chlorine Uzboy FEB 2010.doc FEB

22 Chlorine gas from the electrolysers is routed to the chlorine gas cooler and cooled to approx. 20 C against cooling water. The chlorine containing condensates obtained from the coolers are routed to the dechlorination tank. The main chlorine line is connected to two chlorine seal pots to protect the electrolysers against overpressure and underpressure. Then the cooled chlorine gas is sent through the chlorine demister for aerosol separation before it enters into the chlorine drying unit Unit 06: Chlorine Drying Wet chlorine gas from the electrolysis is dried in the chlorine drying column by a two-staged drying process with concentrated H 2SO 4 that is circulated counter-currently. The water is absorbed in the sulphuric acid and the acid circuit must be cooled according to the absorption heat released. The dried chlorine is supplied via a demister to the chlorine compression unit. Concentrated H 2SO 4 for drying is delivered by truck and stored in the concentrated H 2SO 4 tank. The discharged diluted sulfuric acid is stored in a tank and recycled to the manufacturer Unit 07: Chlorine Compression Dried chlorine gas coming from the drying unit is compressed by the liquid ring seal type chlorine gas compressor to a pressure of 4 barg. The inlet pressure is controlled by recycling gas from the compressor discharge side. The compressed chlorine gas is cleaned from liquid mist by a mist separator and then directly sent to the liquefaction unit Unit 08: Chlorine Liquefaction, Storage and Loading Chlorine liquefaction The compressed chlorine is fed to the chlorine liquefaction unit and is condensed in a heat exchanger against refrigerated water. The refrigerated water is provided by a refrigeration unit. The refrigeration unit consists of two screw compressors systems for the closed refrigerant cycle. The refrigerant used in this unit is the environmental friendly type R 507 according to DIN EA Chlorine Uzboy FEB 2010.doc FEB

23 Liquid chlorine storage The liquefied chlorine is stored in three 50 t liquid chlorine tanks at a pressure of approx. 4 bar and a temperature of approx. 10 C. A forth tank of the same design will be installed as an additional emergency tanks. In an emergency case the total volume of stored chlorine can be transferred from the storage tank to the emergency tank. Each tank is installed in a separate concrete with the side walls higher than the tank. In case of leakage the heavy chlorine gas will be retained in the concrete box and is exhausted by the chlorine absorption unit. Liquid chlorine filling station Liquid chlorine from the storage tank is filled into chlorine transport containers or into rail tank cars. The connection to the containers or to the tank cars is provided by loading arms for the liquid phase and for gas balancing. The filling station is arranged in a closed compartment that is also exhausted by the chlorine absorption unit in case of leakage Unit 09: Catholyte Section Catholyte is fed to the inlet sub-header of the electrolyser by a caustic soda pump and then supplied to each catholyte compartment through a flexible hose which connects the header with each cell compartment. In order to make up for the product caustic soda that is removed from the cycle demineralised water is fed to the catholyte inlet main header under concentration control. An catholyte cooler is installed on the catholyte feeding line to maintain the required catholyte inlet temperature. By electrolysis, hydrogen gas and caustic soda are produced in the catholyte compartments. The mixture of hydrogen gas and catholyte is discharged from the cells through flexible hoses into the outlet header, where it is collected and separated in the catholyte separator. Hydrogen gas is collected in the main hydrogen gas lines and sent to the hydrogen gas treatment section under pressure control. Catholyte is collected in the caustic soda tank. From there it is recycled to the electrolysis, product caustic soda is withdrawn from the cycle under level control in the caustic soda tank according to the production rate of the electrolysis and sent to the evaporation and flaking unit. 2. EA Chlorine Uzboy FEB 2010.doc FEB

24 Hydrogen cooling Hydrogen from the separators is cooled to C against cooling water. The cooled hydrogen is then passed through a demister. The vapour condensate from the cooler is collected in a condensate tank and sent to the caustic dilution station. The main hydrogen line is connected to seal pots in order to protect the electrolysers against over pressure. The hydrogen is supplied to the HCl unit, the rest that is not consumed is discharged to the atmosphere (emission source A-05) Unit 10: Chlorine Absorption and Hypochlorite Production Chlorine absorption Chlorine reacts with caustic soda to form sodium hypochlorite according to following equation: 2 NaOH + Cl 2 NaOCl + NaCl + H 2O This reaction is utilised to continuously eliminate small chlorine containing streams from different sources inside the plant, to absorb major quantities of chlorine in an emergency case and also to produce NaOCl solution. In a first absorption column caustic soda is continuously cycled through the column to absorb small chlorine and hypochlorite containing streams mainly from the tank farm. The remaining inert gases containing only very small quantities of chlorine are sent to atmosphere (emission source A-03). The maximum hypochlorite concentration in the cycle is limited to a certain concentration that allows the additional absorption of the plant's total production rate of 1650 kg/h for a period of 20 min or the absorption of the chlorine exhausted from the storage tanks and the loading station. Hypochlorite production Caustic soda containing some hypochlorite from the chlorine absorption column is circulated over the hypochlorite column with a constant flow rate. Chlorine is introduced under flow control and the concentration of the hypochlorite in the circulating solution is monitored. The heat of reaction is removed by a cooler in the circuit. When the specified concentration of 170 mg/l is reached the chlorine flow is stopped and the produced hypochlorite is pumped to the hypochlorite storage tank farm (unit 19). 2. EA Chlorine Uzboy FEB 2010.doc FEB

25 Unit 11: Caustic Soda Evaporation and Flaking Evaporation The membrane electrolysis produces caustic soda with a minimum concentration of 32 wt% NaOH. This solution with a temperature of about C will directly be fed to the caustic soda evaporation plant. It is preheated by using steam from the next evaporation step. In a falling film evaporator the concentration of the caustic soda is increased to 60 wt%. The evaporator is operated with 2 bar steam. Falling film concentration The 60% caustic soda solution from the evaporation is fed to a specially designed falling film concentrator. During a single pass through this concentrator the NaOH solution is dehydrated from 60% to 98 %. The caustic soda rinses down in a film around the inner wall of the tubes of the concentrator and is heated to a temperature above the melting temperature of solid NaOH. The generated vapour flows downwards in the centre of the tube to the vapour separator. The steam generated in the tubes is used for preheating the caustic soda feed to the first evaporation step. The required heat is transferred by molten heat transfer salt. The heat transfer salt is circulated from a tank through a gas fired heater where it is heated to approx. 430 C. The hot salt flows counter current in the double jacket of the concentrator element and is returned to the molten salt tank. The gas fired heater has a capacity of approx. 2 MW. The flue gas is sent to the atmosphere via an flue gas exhaust pipe (emission A-02). In order to protect the final concentrator from heavy corrosion by high concentrated caustic soda, sugar in form of aqueous solution is added to the 60% caustic soda solution. The sugar solution (concentration approx. 5-10%) is prepared in dissolving tank and dosed to the process by a metering pump. 2. EA Chlorine Uzboy FEB 2010.doc FEB

26 Flaking and bagging The anhydrous caustic soda melt is fed by gravity flow to a specially designed flaking machine. The principle of the flaking machine is based on a rotating, water-cooled cylinder, dipped into a dipping pot which is constantly fed by caustic soda melt. The film that forms on the ribbed surface of the cooling cylinder crystallizes and is scraped-off from the cooling cylinder by scraping knives. The flakes are fed by gravity to a semi-automatic bagging scale. The bagging scales is of airtight design in order to avoid moisture pick-up of the hygroscopic flakes. Fine caustic particles escaping from the filling nozzle of the bagging scale are exhausted via a water washing vessel to the atmosphere (emission source A-06) Unit 12: HCl Synthesis In the HCl synthesis unit a 32 % HCl solution is produced. The unit consists of a HCl synthesis furnace with a falling-film absorber and a scrubber. HCl is formed by the reaction of chlorine with hydrogen: Cl 2 + H 2 2 HCl In the HCl synthesis reactor, chlorine and hydrogen react exothermically. The burner is made of ceramics and the reactor including cooling water jacket is made of graphite. Gaseous HCl from the top of the reactor is routed to the absorber. The absorber is a graphite tubular absorber with HCl gas and demineralised water as absorbent inside the tubes and cooling water at the shell side. The concentration of the hydrochloric acid at the outlet of the absorber is controlled by the demineralised water feed. The product hydrochloric acid is collected in a tank and sent from there to the hydrochloric acid storage tanks in the tank farm (unit 19) by the HCl pump and also distributed in the chlorine alkali plant for internal consumers Unit 16: Utilities Gas turbine unit 12 barg steam and electrical energy are provided by a gas turbine unit with two gas turbines. The electric output is 6 MW (6 kv) each, i.e. the electricity demand of the electrolysis can be covered with one turbine. Both turbines also can be operated simultaneously to supply electricity to the local supply grid. 2. EA Chlorine Uzboy FEB 2010.doc FEB

27 The gas turbine units consist mainly of the air intake with pulse filters, the air compression, the combustion chamber, the turbine part and the lubrication oil system. The power generator is connected by a gear drive to the turbine. The gas turbine can be started by an integrated starter motor. In a flue gas tube boiler the steam is generated at 12 barg, which will be consumed in the plant. Boiler feed water is supplied by a de-aerator, including a feed water tank and boiler feed water pump. The flue gas is sent to the atmosphere via an individual stack per unit (emission source A-01). Steam 12 bar Steam is needed for the caustic soda evaporation and flaking unit, 2 bar steam is also used for evaporation and flaking and also for brine and caustic soda warming. 12 bar steam is supplied by the gas turbine, 2 bar steam is provided by depressurisation of 12 bar steam. Natural Gas Natural gas (approx. 2 x 2800 m³/h) is used for the gas turbine and for the caustic soda flaking heater.(approx. 300m³/h) It is supplied by a branch pipeline that is connected to an existing pipeline from Ashgabat to Balkanabat. Demineralised Water Demin water with a total demand of approx. 30 m³/h is used for the regeneration of the ion exchanger, washing of membranes, as absorption water for HCl synthesis, for the catholyte and for make-up cooling water. Demin water is produced from process water supplied by a branch pipeline from an existing pipeline from Ashgabat to Balkanabat by applying a membrane unit. The wastewater from the membrane unit containing the salts removed from the process water is sent to the wastewater system (wastewater W-01). Compressed and Instrument Air A compressed and instrument air unit will be provided for supplying air in the required quantity and quality. Nitrogen Nitrogen is required for flushing the hydrogen system before start-up and after each shutdown of the electrolysis and HCl synthesis reactor. Nitrogen will be supplied from a liquid nitrogen storage tank to be filled by tank trucks. 2. EA Chlorine Uzboy FEB 2010.doc FEB

28 Cooling Water The cooling water consumers are supplied by a closed cooling water circuit including four cooling towers with a capacity of 250 m³/h each. Demin water is taken as make-up. Blowdown from the cooling water cycle is sent to the wastewater system (wastewater W-03). Refrigerated Water Refrigerated water is required for cooling the sodium hypochlorite as well as the chlorine gas before drying. The refrigerated water is provided by a refrigeration unit. The refrigeration unit consists of two screw compressors systems for the closed refrigerant cycle. The refrigerant used in this unit is the environmental friendly type R 507 according to DIN Unit 19: Tank Farm and Loading The tank farm consist of the following units: Sodium hypochlorite storage with four tanks (4 x 50 m³) Product HCl storage with three tanks (3 x 940 m³) Concentrated sulfuric acid storage with one tank (35 m³) Diluted sulfuric acid storage with one tank (35 m³) The HCl and NaOCl tanks are operated as closed systems, i.e. the gas phase displaced during filling of the tanks is routed to the chlorine absorption system. Truck loading is performed by gas balancing; the displaced volume from the truck tanks is routed back to the storage tank. Thus, the tank operation is free of atmospheric emissions. Solid storage Solid chemicals (mainly alpha cellulose, BaCO 3, Na 2CO 3, Na 2SO 3, sugar) are supplied in bags by trucks and stored in the chemical warehouse Process control The plant operation is controlled by a computerised DCS (distributed control system) from the control room. Plant safety functions are performed by an emergency shutdown system and additional fire and gas detection systems, that are independent of the DCS. The operator interfaces, consoles, terminals, cabinets etc. are located in the control building. 2. EA Chlorine Uzboy FEB 2010.doc FEB

29 3 Emissions, effluents, discharges This chapter describes effluents, discharges, emissions and consumptions of the plant as such, i.e. irrespective of the actual local environment. The data are based on the selected technologies and standard state-of-the-art mitigation measures. The impact on the actual local environment in terms of ground level concentrations, noise levels etc. will be discussed in chapter Air Emissions Emission sources Air emissions no. source type duration height m diameter m flue gas dry, normal conditions m³/h component emission concentration in flue gas mg/m³ average emission flow rate A-01 gas turbine stack continuous x NOx kg/h A-02 flaking unit heater stack continuous NOx 200 0,7 A-03 chlorine absorption vent continuous HCl 30 Cl 2 3 0,001 0,0001 A-04 HCl reactor vent continuous HCl Cl A-05 hydrogen excess vent continuous H A-06 bagging exhaust vent continuous NaOH dust All flue gas volumes are under normal conditions and dry. Source A-01: Gas turbine The two gas turbines have a thermal capacity of 30 MW each (2 x 100 %) and are designed as light-weight, high-efficiency, heavy-duty industrial gas turbines. The turbines are equipped with a dry low emission combustor for a maximum NOx flue gas concentration of 125 mg/m³, 2. EA Chlorine Uzboy FEB 2010.doc FEB

30 which is in compliance with the World Bank requirement 1. SO 2 and particulate emissions are not relevant because sulfur-free sales quality natural gas is used as fuel gas. Both turbines can be operated simultaneously. Source A-02: Flaking unit heater The flaking unit heater is a small gas fired process furnace with a thermal capacity of approx. 2 MW. By applying low Nox burners an NOx concentration of 200 mg/m³ can be achieved. The World Bank requirement 1 would be 320 mg/m³. SO 2 and particulate emissions are not relevant because sales quality natural gas is used as fuel gas. Source A-03: Chlorine absorber In continuous operation chlorine from smaller offgas streams - mainly from the HCl and NaOCl storage tanks - is absorbed by NaOH to form hypochlorite. Chlorine and HCl are absorbed quantitatively. According to the German TA Luft 2 an emission flow rate of less than 150 g/h for HCl and 15 g/h for Cl 2 is irrelevant, i.e. no mitigation measures have to be applied. The emission of this source is well below these limits. It can be considered as irrelevant. Source A-04: HCl reactor In the HCl reactor chlorine reacts with hydrogen to form HCl. Chlorine reacts quantitatively as hydrogen is present in excess, the remaining concentration of chlorine is very low. The formed HCl is absorbed in water. The remaining concentration is approx. 30 mg/m³. The offgas consists mainly of unreacted hydrogen and for this reason the overall quantity of the offgas is low. According to the German TA Luft an emission flow rate of less than 150 g/h for HCl and 15 g/h for Cl 2 is irrelevant, i.e. no mitigation measures have to be applied. The emission of this source is well below these limits. It can be considered as irrelevant. Source A-05: Hydrogen excess The hydrogen produced by the electrolysis is mainly consumed for HCl production. The excess is vented to the atmosphere. Hydrogen is not considered a contaminant and there are no emission standards. The ventgas does not contain any other substances. The source is therefore not a relevant emission source. 1 Pollution Prevention and Abatement Handbook, World Bank Group, July Thermal power generation 2 First General Administrative Regulation Pertaining the Federal Immission Control Act, EA Chlorine Uzboy FEB 2010.doc FEB

31 Source A-06: Bagging exhaust To reduce dust contamination from the bagging station the air is exhausted and cleaned by water washing. The remaining concentration of particles is 20 mg/m³. According to the German TA Luft an emission flow rate of less than 15 g/h is irrelevant, i.e. no mitigation measures have to be applied. The emission of this source is well below this limit. It can be considered as irrelevant. Total emissions The total emissions of the plant are summarised in the following table: Total emissions contaminant kg/h NOx 21 Cl HCl NaOH particles 0.03 The only relevant emission is NOx from combustion. There are no relevant sources for chlorine and chlorine compounds. Stack height calculation The minimum stack height has been calculated according to the German TA Luft for the gas turbine and the flaking unit heater. The stack height calculations are attached (Annex 1). 2. EA Chlorine Uzboy FEB 2010.doc FEB

32 3.2 Environmental noise Environmental noise no. source duration environmental noise limit db(a) total plant continuous 70 at any affected permanent workplace outside the plant battery limit Control of noise is an important issue in the design of the individual equipment items during the detailed engineering phase. The plant will be designed according to state-of-the-art noise reduction techniques and according to the local legislation. According to World Bank standards the noise requirements are based on the susceptibility of adjacent areas taking into account land-use planning and the actual use of the land. The basic requirement is a sound pressure level of 70 db(a) for workplaces in neighbouring industrial areas. The plant is thus designed to achieve a sound pressure level of 70 db(a) at battery limit. Taking into account the dimensions of the plant site the requirement of 70 db(a) at battery limit is equivalent to a total sound power level of 110 db(a). An alkaline chlorine production plant does not contain any noise relevant components; only the gas turbine and the cooling towers will contribute significantly to the overall sound power level, 110 db(a) will not be exceeded and can be taken as basis for a conservative assessment. 3.3 Water demand and wastewater discharge Water demand Water demand no. source duration flow rate m³/h process water demand continuous EA Chlorine Uzboy FEB 2010.doc FEB

33 3.3.2 Wastewater Wastewater no. source duration flow rate m³/h daily average dry weather component concentration mg/l W-01 demin water reverse osmosis unit W-02 brine ion exchange unit W-03 cooling tower blow-off continuous 13 mineral salts (Ca, Mg) intermittent 1 mineral salts (Ca, Mg) intermittent 1 mineral salts Ca: 960 mg/l Mg: 440 mg/l Na: 3800 mg/l Cl: 6400 mg/l W-04 sanitary wastewater intermittent 0,1 normal sanitary wastewater composition The overall wastewater discharge is approx. 15 m³. The difference between water input and output is the water contained in the products, in residues and losses by the cooling towers. The process wastewater streams contain only mineral salts that have to be discharged from the process to maintain the functionality of the electrolysis or the cooling water system. The wastewater does not contain any hazardous components. 3.4 Spillage to surface water, groundwater and soil The solid and liquid substances handled in the plant are mainly mineral salts or acids without any relevant toxicity. The following measures are applied to prevent continuous or accidental losses into the ground: Equipment is designed according to the medium contained, to pressure, temperature and other process requirements to prevent any leakage or spillage. Materials are selected according to well proven international standards taking into account the physical and chemical properties of the storage media. Storage tanks are equipped with high level alarms as a safeguard against overfilling. Storage areas for liquids are impervious to the hazardous liquids. Spillage will be retained by bunding. 2. EA Chlorine Uzboy FEB 2010.doc FEB

34 Manual processes such as loading and offloading are subject to special procedures and will be performed by specially trained personnel only. Process equipment is generally arranged on concrete surfaces; liquid leakage will be collected in appropriate retention facilities. Storage areas for solids are sheltered against precipitation. 3.5 Waste management The chlorine alkaline process as such does not produce process related chemical waste; it is practically free of any unwanted byproducts. The bulk of waste quantities result from the fact that NaCl has to be purified before it can be used as feed for the electrolysis. The overall quantities are governed by the quality of the NaCl feedstock. According to the project specification the following quantities have to be expected: Waste quantities no. source average quantity to be disposed off t/a R-01 mineral residues from salt dissolver recycling disposal 140 landfill R-02 filter cake from brine treatment (mineral residues with filter aid) 3000 landfill R-03 spent electrolyser membranes (polymers) 0.5 (2.5 m³ /4 a) incineration/landfill or recycling by supplier R-04 exchanger resins from brine treatment 1 incineration/landfill R-05 spent electrode material 0,5 recycling by supplier R-06 spent lube oil, oily filters etc. R-07 general waste (non hazardous) 1 recycling or incineration 50 landfill or incineration Source R-01: Mineral residues from salt dissolver 2. EA Chlorine Uzboy FEB 2010.doc FEB

35 Most of the insoluble constituents of the feedstock salt are retained at the bottom of the salt dissolving basin and must be removed discontinuously by manual action or by crane. The remaining solids and mineral sludge is filled into containers and stored at the waste storage area before shipment by trucks. The residues are not soluble and not hazardous and can be landfilled. Source R-02: Filter cake from brine treatment The soluble mineral impurities if the brine are removed by precipitation as barium or calcium salts or hydroxides together with filer aid material (alpha cellulose). The residues are not soluble and not hazardous and can be landfilled. R-03: Spent electrolyser membranes After approx. four years the electrolyser membranes loose their selectivity and have to be replaced. The material is non-hazardous polymers and can be landfilled or incinerated similar to household waste or recycled by the supplier depending on cost and logistic considerations. R-04: Exchanger resins from brine treatment Exchanger resins loose their activity after a certain time and cannot be regenerated any more. They consist of polymer resins that are not hazardous and can be landfilled or incinerated similar to household waste. R-05: Spent electrode material Electrode material is recycled by the supplier. R-06: Spent lube oil Spent lube oil has to be disposed in specialised facilities. There no process-specific aspects. R-07: General waste General waste has to be disposed according to local requirements. There are no process-specific aspects. 2. EA Chlorine Uzboy FEB 2010.doc FEB

36 4 Project alternatives 4.1 Alternative processes Worldwide, three different electrochemical methods are used for chlorine alkaline production: mercury process diaphragm process membrane process New plants exclusively use the state-of-the-art membrane process, which is at the moment the best available technology. Basically, the advantages are: low energy consumption no environmental impact caused by mercury or asbestos high purity of product plant is easy and safe to operate low investment and operating costs less space requirement The membrane process was selected as best available technology without any reasonable technical alternatives. 4.2 Alternative locations Besides the selected location at Uzboy three other locations were assessed during a preliminary project stage. Because of the limited impacts of the plant there are no relevant positive or negative environmental aspect in comparing the selected location with others. Part of the chlorine production is used for iodine production in the neighbouring iodine plant. Thus, the main advantage of the Uzboy location is the reduction of chlorine transport, which is in any case a safety critical operation. 2. EA Chlorine Uzboy FEB 2010.doc FEB

37 5 Impacts of the project 5.1 Air quality Method of assessment The impacts on ambient air quality of the emissions from the plant have been assessed by calculating ground level concentrations (GLC). The present study uses a dispersion calculation model (AUSTAL 2000) according to the German TA Luft. This procedure is a legal requirement in Germany and is similar to other dispersion modelling programmes being used in the EU or the USA. The model uses the Lagrange dispersion model for the individual sources. The input requirements consist of meteorological data and emission source data Emissions source data are source diameter, source height, total flue gas flow, flue gas temperature, and flow rate of individual contaminants The modelling process consists of three steps: First the stack gas plume rise after exiting the stack is calculated based on the heat content of the flue gas, the physical properties of the stack and the dispersion classes. This results in an effective stack height. In a second step the dispersion of plume components from the effective stack height is calculated according to the Lagrange dispersion model. The dispersion depends on dispersion factors which reflect the dispersion classes. The model calculates ground level concentrations for a given location as a yearly average. The results are incremental concentrations for the gas treatment plant. These incremental concentrations have to be added to the base line concentrations. The emissions of the plant are more or less constant. The fluctuations of the ground level concentrations are mainly due to different weather conditions. Dispersion calculations are always based on numerous assumptions and constraints and their reliability should not be overestimated, however, they are applied as standard procedures in air quality planning for many years all over the world. 2. EA Chlorine Uzboy FEB 2010.doc FEB

38 5.1.2 Baseline conditions and project impact According to the German TA Luft the area for which the ground level concentration has to be calculated depends on the height of the highest stack. Minimum requirement is a radius of 1 km. In the case of the alkaline chlorine plant the minimum requirement applies. In order to also include the housing area of Uzboy the radius is extended to 1.5 km. Data regarding the existing air quality do not exist. The impact of the existing industrial activities e.g. by the iodine plant or by near-by oil and gas processing installations could be relevant, but cannot be assessed for the time being due to lack of data. Under these circumstances only the additional impact of the project can be calculated and assessed. As described in chapter 3.1 the only relevant air emission component is NOx. According to EU standards (see e.g. TA Luft 4.2.1) there are maximum allowable ground level concentrations calculated as a yearly average and as an hourly average. The calculated results for the yearly average and the hourly average is shown in the following pages as isolines for the whole calculated area of 3 x 3 km. Relevant for the assessment is the maximum concentration within the housing area as shown in the following table: Ground level concentrations compound parameter maximum incremental ground level concentration relevant EU limits NOx (as NO2) yearly average µg/m³ hourly average The yearly average reflects the distribution of wind directions and shows a maximum in northwesterly direction from the plant according to the prevailing wind direction, which is southeast. The maximum appears at a distance of approx. 1.6 km from the plant. The ground level concentrations closer to the source are smaller due to the effect of the stack and the buoyancy of the flue gas. The maximum hourly ground level concentration is not dependent on the wind direction distribution. Due to the fact that hourly climatic data are not available, the maximum hourly ground level concentrations were estimated from the yearly average figures. As a general result of the assessment it can be stated that the contribution of the plant to the ground level concentration is approx. 1 % of the EU limits. According to TA Luft an incremental impact of a new plant is considered irrelevant, when 3 % of the ground level limit is not 2. EA Chlorine Uzboy FEB 2010.doc FEB

39 exceeded - this is the case here, i.e. no matter what the actual baseline concentration is, the incremental impact of the new plant is not relevant m Dispersion calculation according to TA Luft (AUSTAL 2000) Yearly average ground level concentration component: NOx unit: µg/m³ calculated maximum: EA Chlorine Uzboy FEB 2010.doc FEB

40 m Dispersion calculation according to TA Luft (AUSTAL 2000) Maximum hourly average ground level concentration component: NOx unit: µg/m³ calculated maximum: EA Chlorine Uzboy FEB 2010.doc FEB

41 5.2 Environmental noise The plant is operated continuously without any relevant differences between the day and night noise emission level. Thus, impact discussions can be limited to the night case. According to the World Bank standards the maximal allowable sound pressure level in residential areas during the night time is 45 db(a). Information on the actual baseline figures are not available, however, it can be assumed that the actual sound pressure level is negligible. Based on a sound power level for the whole plant of 110 db(a) the sound pressure levels at the relevant distances in the neighbourhood are calculated according the German TA Lärm (provisional noise calculation A 2.4.3): housing area relevant distance m allowable sound pressure level (night time) db(a) sound pressure level attributable to the plant (night time) db(a) Uzboy The incremental impact of the plant even at the closest housing area in the neighbourhood is 6 db(a) below the relevant limit. Because of the logarithmic addition of sound levels 38 db(a) is irrelevant compared to 45 db(a). Even if the baseline noise level is already in the range of the 45 db(a) limit the new plant would not contribute significantly to the overall noise level. 5.3 Water demand and wastewater discharge The plant will be supplied by a process water pipeline. Due to the relatively small quantity of 45 m³/h it is assumed that the demand will be covered by the capacity of the existing water supply facility. The environmental impacts of water supply are thus not within the scope of this study. The wastewater (approx. 15 m³/h) contains mineral salts - mainly Ca and Mg - at higher concentrations. It does not contain any organic compounds. It will be routed to a local evaporation pond. The evaporation pond is already existing. Due to the fact that the vicinity of the site is characterised by salty marshes the impact of an additional source of salt at this location is acceptable. 2. EA Chlorine Uzboy FEB 2010.doc FEB

42 5.4 Spillage to surface water, groundwater and soil The individual mitigation measures to control continuous and accidental spillage are described in chapter 4. The hazardous potential of salt containing solution to the subsoil at the Uzboy area is low. Thus, relevant impacts are not to be expected. 5.5 Waste management The bulk of solid waste produced by the new plant is residual mineral salt and salt sludges of low solubility. It can be expected that this kind of residue can be landfilled without any relevant risk in the area - the actual impacts have to be studied when the exact location will have been identified. The logistics of waste disposal still have to be worked out in detail. The chlorine alkaline plant does not produce any hazardous waste that could cause any specific problems of disposal. 5.6 Infrastructural impacts The feedstock - salt - will be transported to the plant by trucks. The products will be shipped mainly by truck but also by rail cars. The estimated number of additional truck traffic to and from the plant is approx. 10 per day. The number of workers is approx. 120 working on a five shift schedule. Taking into account that Balkanabat is a city of inhabitants the additional workforce can be hired mainly locally without any relevant impact to the local infrastructure. The existing road infrastructure need not to be improved to deal with the additional traffic. count the limited demand, there are also no relevant impacts on the infrastructure regarding these utilities. All other utilisties - especially electricity and steam - are produced on site. 5.7 Nature and landscape conservation The new plant is located within a larger existing industrial area. The project has no relevant additional negative impact to the nature and the landscape in the area. There are no dedicated protected areas or objects in the relevant vicinity of the plant. 2. EA Chlorine Uzboy FEB 2010.doc FEB

43 6 Process safety The following documentation is based on the requirements for a Safety Report according to the EU Seveso Guideline. The Safety Report has to consist of the following elements: Description of the site and its environment (see 2) Description of the establishment (see 2) Inventory of hazardous substances Safety equipment and measures of protection Possible accidents and its consequences Safety Management System 6.1 Inventory of hazardous substances The inventory of hazardous substances of the gas treatment plant is given in the following table according to the substance categories defined by the EU Seveso II Directive. Safety sheets of the substances are attached (Annex 2). substance category according to Seveso II Annex 1 definition threshold Annex 1 EU Seveso guideline t substance hold-up 2 toxic 50 chlorine 150 t 9 dangerous for the environment 100 sodium hypochlorite 150 The relevant threshold limits for chlorine and for sodium hypochlorite are exceeded, i.e. the plant would be safety relevant according to the EU Seveso II Directive. 2. EA Chlorine Uzboy FEB 2010.doc FEB

44 6.2 Safety equipment and measures of protection General safety hazards The safety risks of a chlorine alkaline electrolysis plant are mainly governed by the toxicity of chlorine. Inside the plant the risk is concentrated in the chlorine tankage area - compared to the tank area the chlorine inventory in the rest of the plant is only small. A second hazard are explosive mixtures from hydrogen and air or chlorine. Apart from hydrogen the substances handled in the plant are not flammable, i.e. the fire risk is negligible Site Layout and Spacing The plant has been designed according to norms and standards dealing with the overall layout of hydrocarbon processing plants and the spacing between plant units and individual equipment. Entrances and internal roads are designed to facilitate access of emergency response forces under all relevant weather conditions and incident scenarios. The overall site is subdivided into general areas (blocks) with a certain maximum size depending on the specific risk and the availability of fire fighting equipment. Access roadways are provided between the blocks to allow access to each block from at least two directions. Road widths and clearances are sized to handle large moving equipment and emergency vehicles Design of equipment The design and specifications of equipment, rotary equipment, piping including valves, flanges etc. depend on the media being used and on operating parameters such as operating pressure and temperature. The choice of materials, as well as design and specifications is compliant with the relevant technical norms and standards. The material flows on which this is based are documented on process flow diagrams, showing mass balance, pressure, temperature and flow rate for the individual pieces of equipment. The technical data for the individual equipment and machinery are documented on equipment lists or P&I diagrams. Piping is designed and selected according to pipe classes. In these pipe classes the required materials, dimensions, flanges, seals, valves etc. are specified in detail. 2. EA Chlorine Uzboy FEB 2010.doc FEB

45 Specific design requirements for chlorine plants According to relevant standards there a specific design requirements for chlorine plants (e.g. by the Safety requirements for production, storage, transport and utilisation of chlorine - PB ). The plant will be designed to comply with these standards. Main requirements are: All nozzles at chlorine storage vessels must be arranged in the gas phase. Piping principally has to be welded, flange connection are permitted only if they are technically inevitable. All chlorine piping has to be protected from incidental mechanical damage. Connecting piping at chlorine vessels has to be equipped with redundant shutoff valves at the vessel. The chlorine and also the sodium hypochlorite tankfarm has to be equipped with en emergency tank as a standby system in case of a leakage. It must be able to hold the volume of one storage tank. The storage facilities have to equipped with a suitable retention room according to the volume of one storage tank. The dispersion of chlorine gas clouds from storage and filling in case of leakage have to be confined by concrete walls with an exhaust system to the chlorine emergency absorption. In addition to that mobile equipment such as water curtains will be provided to confine and dilute chlorine gas clouds Safety functions by process control systems Classification Process control is an important element of the total plant safety. With regard to their safety function, all control functions are categorised into operational, monitoring and safety instrumented functions and designed accordingly according to relevant international standards. Operational control equipment The purpose of operational control equipment is to ensure that installations operate properly within the acceptable range specified. It includes the automation functions required for the production process. That includes measurement and control of all process variables relevant to product quality, including functions such as registration and logging. The functions of the operating control equipment are continuously operative and subject to ongoing plausibility checks by operating personnel. Monitoring control equipment When installations are operating correctly, monitoring control equipment responds in circumstances where continued operation would not jeopardise safety, i.e. they respond on the borderline between the acceptable range and the permissible error range for process variables. Monitoring control equipment signals permissible faults, in order to initiate increased attention or manual intervention by operating personnel or intervenes automatically to return process variables to the acceptable range. In most cases monitoring control 2. EA Chlorine Uzboy FEB 2010.doc FEB

46 equipment is arranged to respond before any primary safety devices is activated - i.e. pressure high will be signalled before a safety valve will open. Monitoring functions are either switch (S) or alarm (A) functions. Safety instrumented functions (SIF) Wherever primary safety devices, such as safety valves or rupture discs cannot be used or are not sufficient used alone, safety instrumented functions equipment is used in order to exclude the possibility of a piece of equipment exceeding the design parameters. They are specially marked on the PIDs. Safety instrumented functions, in conjunction with the primary safety devices, prevents non-permissible states in the facility that could directly cause harm to personnel or serious material damage and are designed in such a way as to be functionally independent from all the other functions of the facility, thus guaranteeing the safety of the facility under all operating conditions, without special intervention by the operating personnel being needed or even possible. No special requirements apply to operating or monitoring process control functions; they are treated like ordinary operating equipment. These functions are not safety relevant and will not be discussed in this report. For each individual safety instrumented functions a Safety Integrity Level (SIL) is defined as a relative level of risk-reduction provided by a safety function, or to specify a target level of risk reduction. SIL is a measurement of performance required for a Safety Instrumented Function (SIF). Four SILs are defined, with SIL4 being the most dependable and SIL1 being the least. A SIL is determined based on a number of quantitative factors in combination with qualitative factors such as development process and safety life cycle management. Safety integrity levels are defined according the technical standard IEC "Functional safety - Safety instrumented systems for the process industry sector" Pressure relief systems Parts of the process plant - especially the liquid chlorine section - are operated under pressure and thus are classified as pressure equipment. Pressure equipment has to be designed, manufactured and tested according to requirements of the applicable national or international standards. Pressure equipment is designed for a specified maximum operating pressure and temperature. If the process can exceed these parameters the equipment has to be protected by safety valves or safety instrumented functions. A safety valve opens automatically when the set pressure of the valve is exceeded. The valve disk is lifted and makes the flow area available for pressure relief. In general, the full lift is attained within a pressure rise of no more than 10 % above the set pressure. The disk reseats when the pressure has dropped below the set pressure. In this way, the amount of vessel contents released is only that needed for instantaneous pressure limitation. 2. EA Chlorine Uzboy FEB 2010.doc FEB

47 The safety valves of the liquid chlorine vessels are equipped with a additional rupture disk to protect the valves from corrosion Emergency shut down system The plant is equipped with an emergency shutdown system (ESD). The ESD is activated by specific process parameters or manually by the operators. In case of activation of the ESD the electrolysis is stopped and the produced chlorine is sent to the emergency absorption system Emergency absorption system The plant is equipped with an emergency chlorine absorption system (see ). The system is designed to absorb the total production capacity of the plant (1650 kg/h) for a period of 20 minutes that is sufficient to shutdown the plant including the electrolysis. The absorption system is also designed for absorbing chlorine from air that is exhausted from the chlorine storage and filling units in case of chlorine leaks Explosion protection Hydrogen is a flammable gas and can form explosive mixtures with air and also with chlorine. A gas-phase explosion is initiated by an ignition source, delivering sufficient energy and having a suitable energy distribution. The reaction initiated propagates spontaneously through the mixture. Such combustion reactions are accompanied by the release of a large quantity of energy with increases in temperature and pressure (and often also by the formation of dangerous reaction products). The hazards associated with an explosion are thus governed by three factors : Occurrence of an explosive mixture Presence of an effective ignition source Effects of an explosion Hydrogen chlorine mixtures can only occur inside the equipment. The occurrence of such mixtures is controlled by an appropriate plant design and by process control. Hydrogen air mixtures can occur in case of hydrogen leakage from hydrogen containing equipment. To avoid ignition the relevant zones are explosion protected. 2. EA Chlorine Uzboy FEB 2010.doc FEB

48 For the total plant the relevant explosion hazards will be identified in a systematical way during further engineering. The resulting measures are documented in the explosion protection document Monitoring, Alarm and Communication Systems Gas detection systems Areas where chlorine is handled are equipped with a gas detection system. An alarm signal is given when a threshold concentration is reached. The power supply is backed up by batteries. If there is a power failure, the alarm is triggered on the failure to safety principle. Alarms are signalled on a gas monitoring display in the central control room. The gas detection system is calibrated at regular intervals. This enables reductions in the detection sensitivity, caused for example by catalyst poisoning, to be recognised early. The calibration is carried out using a test gas of which the concentration is known Communication Systems Pushbutton alarms are installed in buildings in unit fields. The units are equipped with an intercom system to the control room. The control room alerts the emergency dispatcher via telephone. Personnel in the facility are alerted by a centralized sound alarm Fire protection There are no process specific fire protection requirements because of the negligible fire risk that is attributed to the process. The fire protection for buildings such as the control buildings will be designed according to the local requirements. Fire water is stored in a fire water tank. The capacity will be designed according to local requirements. A fire brigade is at site. 2. EA Chlorine Uzboy FEB 2010.doc FEB

49 6.3 Hazard Identification and Risk Assessment Process risks A systematic process hazard assessment will be performed during detailed engineering to identify process risks and to define the necessary safeguards External risks Public roads There is no major public road in the relevant vicinity of the plant. Site traffic Access to the controlled process site is limited to vehicles which are necessary for operational purposes only. A speed limit of 30 km/h applies to all site traffic. A kerb around the units protects them from being hit by traffic so that damage to any of the facility s components in this way can be ruled out. Special organisational procedures also apply for the entire site to vehicles and haulage equipment, which due to their height could touch pipe racks. These procedures range from special instructions to drivers to vehicles being accompanied by site security personnel. Access of vehicles to the process unit areas is subject to permit-to-work procedures. Air traffic There is no airport in the relevant neighbourhood. Pipelines The existing gas supply pipeline does not create a significant risk for the chlorine containing equipment due to distance and the arrangement of the chlorine storage facilities. Industrial installations There are no industrial installations in the relevant vicinity that could expose the chlorine alkali plant to a significant additional risk. The iodine plant does not exhibit any major fire or explosion risk to the chlorine alkali plant. 2. EA Chlorine Uzboy FEB 2010.doc FEB

50 6.3.3 Natural hazards Flooding There has never occurred any flooding of the site area. The site area is at a higher elevation as the surrounding area. Earthquakes The plant is located in a dedicated area with seismic risks. Seismic loads were taken into consideration according to Turkmen construction standards. Exposure to weather Wind load for the relevant equipment is calculated on the basis of local data. Equipment is protected against lightning strikes by the lightning arresters and earthing systems installed Hazards from action by unauthorised persons The site is designed to provide extensive protection against action by unauthorised persons: The site is enclosed by robust perimeter fencing. Access to the site is restricted and checked at the main gate. There is another controlled gate to the process area. Access to the offices or to the process area is possible only to individuals with company identification. Regular patrols by the security service ensure that the site is adequately protected. Each individual must report to the shift foreman before entering a process unit. Access for maintenance is controlled according to the permit-to-work system. The site is continuously lighted. 2. EA Chlorine Uzboy FEB 2010.doc FEB

51 6.4 Consequence analyses Consequence analyses are performed to identify the residual risk of safety relevant plants and to assess the adequacy of safeguards and the safety distance to neighbouring objects. If the modelling results in relevant offsite consequences further countermeasures have to be considered. The results should also be used for public emergency planning if necessary. The consequence analyses is performed for two different cases: chlorine release due to pipe rupture outside the confined area (connecting pipeline) chlorine release from storage tanks inside confined area with exhaustion of the chlorine to the emergency absorption system 2. EA Chlorine Uzboy FEB 2010.doc FEB

52 6.4.1 Chlorine release from piping Consequence Analysis release of chlorine from piping/equipment outside containment heavy gas cloud formation and dispersion of toxic gas parameter 1 Substance Chlorine is handled in the gaseous state and as liquefied gas. The most relevant releases in terms of quantity will appear in the liquid phase where both the pressure and the density is considerably higher. It is assumed that the leakage will take place at the discharge side of the chlorine compressor after refrigeration and liquefaction, i.e. under storage conditions of 4 bar/10 C. 2 Leakage diameter The pipe size for the liquid chlorine line between the storage and the rail tank car loading station is DN 50. A full cross sectional rupture of the pipe is assumed. 3 Released quantity In this case the shutoff valves at the chlorine tank and at the loading station will be closed automatically by the gas detection system and the chlorine compressor is stopped. The quantity released is calculated with the programme package ALOHA 3 for the storage conditions as mentioned above. 4 AEGL-2 radius AEGLs represent threshold exposure limits for the general public and are applicable to emergency exposure periods ranging from 10 minutes to 8 hours. The three AEGLs have been defined as follows: AEGL-1 (0.5 ppm, 60 min) is the airborne concentration of a substance above which it is predicted that the general population, including susceptible individuals, could experience notable discomfort, irritation, or certain asymptomatic nonsensory effects. However, the effects are not disabling and are transient and reversible upon cessation of exposure. AEGL-2 (2 ppm, 60 min is the airborne concentration of a substance above which it is predicted that the general population, including susceptible individuals, could experience irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape. AEGL-3 (20 pp,, 60 min) is the airborne concentration of a substance above which it is predicted that the general population, including susceptible individuals, could experience life-threatening health effects or death. chlorine, liquid 50 mm 30 g/s for 1 min 770 m 460 m 180 m For external emergency response planning purposes normal AEGL-2 is taken as a limit. The area, in which this limit can be exceeded is shown on the aerial photograph. It has to be kept in mind that this is a circular area because all wind directions are possible in case of an accident. The actual AEGL-2 area for a distinct wind direction is smaller and shown as dotted ellipse for south-easterly wind. 3 US EPA, 2. EA Chlorine Uzboy FEB 2010.doc FEB

53 AEGL-2 Chlorine release from pipe: AEGL-2 zone Onsite effects AEGL-3 is exceeded within the chlorine plant and within the total site. A common emergency plan for the whole site will be in place. According to this plan the operators and other workers are trained for such emergency cases. Escape filters are available. Offsite effects At the housing area AEGL-2 is not exceeded. Additional technical measures are not required. The safety distances are adequate. 2. EA Chlorine Uzboy FEB 2010.doc FEB

54 6.4.2 Chlorine release from storage Consequence Analysis release of chlorine from a storage tank inside containment with exhaustion to emergency absorber, heavy gas cloud formation and dispersion of toxic gas parameter 1 Substance The storage tanks do not have any connection in the liquid phase. A leakage in the liquid phase at the vessel is extremely unlikely. It is assumed that a leak occurs in the gas phase with. 4 bar/10 C. 2 Leakage diameter A leak with a cross section of DN 50 is assumed according to the largest pipe connected to the tank. 3 Released quantity In this case there is no automatic shutoff, because the tank as such is leaking. The gas phase will quickly depressurise, i.e. flash, and the liquid will cool down to the equilibrium temperature at atmospheric conditions (- 36 C). The maximum relevant release flow is during the flash period. The calculated release is 100 kg/min for 3 min. The release rate from the cold chlorine is considerably lower. For this reason, it is assumed that the vessel is nearly empty, so that the total volume will be depressurised. The exhaustion to the emergency absorber is started automatically by the gas detectors. It is assumed that the exhaust system to the emergency absorption will have an efficiency of 95 %. The remaining emission is 5 kg/min for 3 min. 4 AEGL-2 radius AEGLs represent threshold exposure limits for the general public and are applicable to emergency exposure periods ranging from 10 minutes to 8 hours. The three AEGLs have been defined as follows: AEGL-1 (0.5 ppm, 60 min) is the airborne concentration of a substance above which it is predicted that the general population, including susceptible individuals, could experience notable discomfort, irritation, or certain asymptomatic nonsensory effects. However, the effects are not disabling and are transient and reversible upon cessation of exposure. AEGL-2 (2 ppm, 60 min is the airborne concentration of a substance above which it is predicted that the general population, including susceptible individuals, could experience irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape. AEGL-3 (20 pp,, 60 min) is the airborne concentration of a substance above which it is predicted that the general population, including susceptible individuals, could experience life-threatening health effects or death. chlorine, gas 50 mm 5 kg/min for 3 min 1600 m 920 m 320 m For external emergency response planning purposes normal AEGL-2 is taken as a limit. The area, in which this limit can be exceeded is shown on the aerial photograph. It has to be kept in mind that this is a circular area because all wind directions are possible in case of an accident. The actual AEGL-2 area for a distinct wind direction is smaller and shown as dotted ellipse for south-easterly wind. 2. EA Chlorine Uzboy FEB 2010.doc FEB

55 AEGL-2 Chlorine release from pipe: AEGL-2 zone Onsite effects AEGL-3 is exceeded within the chlorine plant and within the total site. A common emergency plan for the whole site will be in place. According to this plan the operators and other workers are trained for such emergency cases. Escape filters are available. Offsite effects At the housing area AEGL-2 is not exceeded. Additional technical measures are not required. The safety distances are adequate. 2. EA Chlorine Uzboy FEB 2010.doc FEB

56 7 Occupational health impacts 7.1 Number of workers The total number of workers will be approx The plant will be operated continuously. 7.2 Hazardous substances From the occupational health point of view, chlorine and sodium hypochlorite are the most relevant hazardous substances in the plant. Main aspects are: Hazardous substances are handled in closed systems. The workers do not have any direct contact with hazardous substances. The process is fully automated and controlled from the control building. The HSE management system (see chapter 9) will minimise any workplace hazards by health risk assessments and other methods. 7.3 Workplace noise In accordance with the international best practice plant noise during normal operation shall not exceed an equivalent sound level of 85 db(a) over an eight-hour period. This limit may be considered as a noise limit for individual areas, or may be considered as a noise exposure level for personnel on the plant. The best practicable means for noise control shall be used to achieve this limit. For areas where the sound level exceeds the noise limit, the area is posted with safety signs, and ear defenders are provided and have to be worn by anyone in the area. 2. EA Chlorine Uzboy FEB 2010.doc FEB

57 8 Impacts during construction The construction phase of the project will begin with land acquisition and clearance and end on the mechanical completion of the plant. This phase of the project will involve a host of activities like setting up of accommodation camps, deployment of equipment and machinery, increased traffic, deployment of a large workforce and transportation of construction material and manpower to and from the site. The construction phase is characterised by brisk activity and imposes additional demand on the local infrastructure such as roads, water supply, and electricity and also poses constant challenge to maintain hygienic conditions at the construction site and its surroundings. The mechanical erection of the project shall involve extensive use of manpower, machinery and fabricated materials. The construction workforce will be accommodated in a construction camp in an area allocated and approved by the relevant authorities. The construction camp will be removed after completion of the project. Air quality impacts Due to the fact that there are no relevant housing areas in the neighbourhood no special measures have to be taken to mitigate air emissions by construction activities like e.g. dust. Water consumption and wastewater During the construction of the project, water is required for construction, sanitary and drinking purposes. The details of wastewater cleaning during construction still have to be clarified. Waste management There will be additional waste during the construction phase such as damaged materials, excess materials, packaging waste etc. A waste management plan will be set up as part of the general HSE management during the construction phase. Noise Heavy construction traffic, pile driving and general plant construction are likely to cause an increase in the ambient noise levels. However, due to the absence of housing areas this aspect is irrelevant. 2. EA Chlorine Uzboy FEB 2010.doc FEB

58 9 Health, Safety and Environment Management 9.1 HSE Management System The plant will have an integrated HSE management system for health, safety and environmental protection. This management system will fulfil the requirements of a safety management system imposed by the EU Seveso II Directive as well as the basic requirements of ISO A concept for preventing major accidents as required by the Seveso directive is an integrated component of the HSE management system. The basic requirements of the HSE management system are described under the headings of the system cycle shown below: Organisation Policy Risk Management Health Management Safety Management Environmental Management Product Stewardship Continual Improvement Performance Measurement Audit Management Review The system follows the conventional Plan Do Check Act model, starting with the Organisation which carries out the key Risk Management elements. Performance is checked against objectives in the Measurement and Audit section and actions to achieve Continual Improvement complete the cycle. The plant management will issue an HSE policy statement. The policy statement is communicated within the company and key issue of training activities. It includes a commitment to comply with legal requirements and continually improve the effectiveness of the management system. The individual elements and requirements of the HSE management system that the Seveso II directive (Annex III) or ISO demand are listed in the following table. 2. EA Chlorine Uzboy FEB 2010.doc FEB

59 Requirements Element of HSE management system I Organization and personnel Roles and responsibilities of personnel involved in HSE management at all levels in organisation The fundamental obligations of the operator of the establishment are formally delegated to the Site Manager who is the management representative for HSE. He is responsible for the appropriate delegation of all individual duties that are relevant to safety. The principles of delegation (clear definition of competence, clear instructions, provision of necessary funding and monitoring of performance) are also specified. The operative HSE responsibility has been delegated to the individual managers of operations departments. They are responsible for transferring HSE requirements into plant operations. HSE line functions are assisted by specialists for safety, occupational health and environment. Specific personal HSE functions (e.g. safety engineers) are formally appointed in writing. General and specific personal HSE obligations are part of the job descriptions for all operating personnel and line management. Legal requirements are monitored systematically by the safety/environmental department. Information on relevant changes are distributed to the line management or departments concerned. Permit requirements are managed systematically including follow-up of commitment by the responsible operations managers assisted by the safety/environmental department. Documents and records which are subject to the safety management system are managed systematically. Custodians for the documents are nominated. All documents are kept systematically and are easily retrievable for all concerned. Identification of training needs of such personnel and the provision of the training so identified; Personnel are selected on the basis of specified qualification criteria which have been defined for the respective job function. There are special introductory training programmes for new employees. Training needs are identified annually by the line management and recorded in a training plan. Particular atten- 2. EA Chlorine Uzboy FEB 2010.doc FEB

60 Requirements Element of HSE management system tion is paid to the legal requirements applicable to certain activities. For operators a special qualification system is in place, i.e. specific functions are assigned formally to different levels of qualification. According to the respective level each operator has to pass a work safety examination regularly. Special training schedules are in place according to legal requirements as to working with specific safety relevant equipment (e.g. pressure vessels, boilers etc.) Personal training records are kept. Involvement of employees and, where appropriate, subcontractors Contractor personnel receive introductory instructions including examinations on safety matters before beginning their work on the site. Special procedures are in place to achieve an appropriate integration of contractors and their personnel into the HSE management system. II Identification and evaluation of hazards Adoption and implementation of procedures for systematically identifying major HSE risks arising from normal and abnormal operation and the assessment of their likelihood and severity; Plant equipment is subject to legal and non-legal, local and international standards covering all relevant safety aspects in detail. These standards are based on the worldwide experience and hazard identification expertise within the hydrocarbon processing industry from its very beginning. According to the safety management system, for all projects the applicable technical standards have to be clearly specified. HSE requirements are defined as contractual obligations in all engineering, procurement, erection, service etc. contracts. For HSE relevant new units and equipment safety reviews are performed at different stages of engineering and installation. Risks are identified according to formalised procedures (risk assessments). Depending on the safety relevance of the equipment different stages of reviews are chosen. The results are documented. Authorities and - if necessary third-party experts - review the compliance with legal requirements during the permit procedure. Specific safety relevant equipment (e.g. pressure vessels) is subject to further formal reviews and tests before startup and during operation on a regular basis. For these pieces of equipment a passport is kept holding all rele- 2. EA Chlorine Uzboy FEB 2010.doc FEB

61 Requirements Element of HSE management system vant technical data, review and testing results. Before start-up a commission checks compliances with the permit requirements. Specific procedures exist for hazardous area planning. Specific procedures exist as to the management of material safety data sheets (MSDS) to identify potential substance related hazards. Impacts to the environment are identified by keeping inventories of all relevant emissions sources (air, water, waste, noise). III Operational control Adoption and implementation of procedures and instructions for safe operation including maintenance, of plant, processes, equipment and temporary stoppages Written operating procedures exist for all relevant operations. Safety relevant aspects, special precautions, personal protective equipment etc. are covered by these procedures. Such operating procedures exist for all safety relevant activities within the plant including planning, erection/installation, operations, maintenance, loading/unloading, handling of hazardous goods etc. The responsibility for setting up, keeping and reviewing these procedures has been assigned to the management of the individual operations. General safety procedures for the site as a whole cover general safety measures which are not related to specific process operations such as permit-to-work procedures, confined space entry, working in hazardous areas etc. The responsibility for setting-up, keeping and reviewing these procedures has been assigned to the site management assisted by the safety department. Regular inspection and maintenance is carried out on the basis of a systematic inspection and maintenance programme. All inspection and maintenance activities are recorded. Specified safety relevant equipment (pressure vessels etc.) are inspected by special supervisors. IV Management of change Adoption and implementation of procedures for planning modifications to, or ref. to II Identification and evaluation of hazards 2. EA Chlorine Uzboy FEB 2010.doc FEB

62 Requirements the design of new installations, processes and storage facilities; Element of HSE management system Any change of equipment or process including smaller changes is subject to a formalised process of safety reviewing. These reviews cover safe design and installation of the related equipment, necessary changes to existing safety equipment or potential impacts on safety in general. Before the start-up of new or changed equipment safety inspections and tests are performed depending on the safety relevance of the equipment or change. V Planning for emergencies Adoption and implementation of procedures to identify foreseeable emergencies by systematic analysis; Relevant scenarios for major accidents are determined according to a systematic process based on the hold-up of hazardous substances in the individual units. Such effects assessments and the practical experience of the plant fire brigade are used to determine foreseeable emergency incidents (cases), which form the basis for the emergency response planning. Adoption and implementation of procedures to prepare, test and review emergency plans to respond to such emergencies Emergency response plans for the individual operations departments or shops are in place. The details of these plans are defined by a general procedure. The plans comprises - a description of relevant hazards and explosion potential, safety measures, - emergency/evacuation procedures and plans - accident scenarios. The shifts of the respective unit are trained regularly according to this plan. Mock drills are performed together with the safety department and the fire brigade regularly. The findings of these drills are recorded and followed up systematically. An emergency response plan for the plant site is in place. The plan covers among other issues - organisation and responsibilities of emergency response crews - Training of emergency response personnel - Organisation and documentation of mock drills of shop personnel - Organisation and responsibilities in case of an emergency situation - Information to and cooperation with the authorities 2. EA Chlorine Uzboy FEB 2010.doc FEB

63 Requirements Element of HSE management system and neighbouring establishments The plan is revised yearly on the basis of actual incidents, mock drill performance and technical changes. VI Monitoring performance Adoption and implementation of procedures for the ongoing assessment of compliance with the objectives set by the operator s HSE policy and management system, and the mechanisms for investigation and taking corrective action in case of non-compliance The procedure should cover the operator s system for reporting major accidents or near misses, particularly those involving failure of protective measures, and their investigation and follow-up on the basis of lessons learnt; Rounds are performed regularly and systematically on the unit level by the operators. HSE is one of the key issues of these rounds. There are procedures for details of performing rounds including reporting of deviations. HSE inspections/audits are performed at different levels periodically. Audits are performed specialists from safety relevant departments (safety, fire brigade, medical service). A specific procedures deals with all details of this inspection system including scheduling, participants, reporting, evaluation, and follow-up of deviations. Incidents and failures below the emergency threshold are systematically evaluated according to a special procedure in relevant cases by an accident investigation commission. Emergency cases or incident with relevant injuries or losses are investigated in any case. Corrective or improvement measures are incorporated into specifications, instructions and training plans in order to facilitate continual improvement. The frequency of such incidents is monitored and reported to the management. Comprehensive figures are published internally to the employees. VII Audit and review Adoption and implementation of procedures for periodic and systematic assessment of the major-accident prevention policy and the effectiveness and suitability of the HSE management system and its updating by senior management. The HSE management system is subject to internal or external management system audits. The audits are carried out on the basis of an audit plan kept by the safety/environmental department. Results and relevant findings, accident reporting and incident investigation results are compiled to a yearly Safety Report and presented to the site management. On the basis of this report the site management annually performs a formal review of the safety management system and draws up a safety improvement programme. If necessary the safety management system will be updated. The plan is the subject of audits to follow-up implementation. 2. EA Chlorine Uzboy FEB 2010.doc FEB

64 2. EA Chlorine Uzboy FEB 2010.doc FEB

65 Annex 1 - Stack height calculations 2. EA Chlorine Uzboy FEB 2010.doc FEB

66 Annex 2 - Hazardous substances data sheets Chlorine Sodium hypochlorite Hydrogen chloride Sodium hydroxide Sulfuric acid 2. EA Chlorine Uzboy FEB 2010.doc FEB

67 Process Engineering Any exploitation and/ or other utilization, including but not limited to reproduction, dissemination and/ or distribution of this document and its contents are strictly prohibited unless expressly authorized in writing by CAC. Offenders are liable for damages. All rights, including but not limited to all proprietary rights in relation to patents, utility models and/ or other industrial property rights, are reserved. Uzboy Chorine Alkali Plant Gas turbine units Stack Height Calculations 0 Schaaf Rev. Name Date Name Name Date Status Remarks, type of change Prepared, changed Checked Approved Code Project No Document No Sheet Revision EDV-Ident-Nr. X:\38820x41\2009\09_093_Elektrolyse Turkmenistan_SOJITZ\VT\07_Umweltstudie\stack height calc_draft.doc Formblatt CFA 1500E Ausgabe: 02/05 Rev.:01

68 Index of Revisions Any exploitation and/ or other utilization, including but not limited to reproduction, dissemination and/ or distribution of this document and its contents are strictly prohibited unless expressly authorized in writing by CAC. Offenders are liable for damages. All rights, including but not limited to all proprietary rights in relation to patents, utility models and/ or other industrial property rights, are reserved. Rev. Prepared, changed Checked Approved Sheet Remarks, type of change Name Date Name Name Date Status 00 Schaaf First Issue Index of Relevant Documents Document No Title Summary of Revisions Table of Contents Section... Page 1 Introduction Data Results...2 Code Project No Document No Sheet Revision EDV-Ident-Nr. X:\38820x41\2009\09_093_Elektrolyse Turkmenistan_SOJITZ\VT\07_Umweltstudie\stack height calc_draft.doc Formblatt CFA 1500E Ausgabe: 02/05 Rev.:01

69 Any exploitation and/ or other utilization, including but not limited to reproduction, dissemination and/ or distribution of this document and its contents are strictly prohibited unless expressly authorized in writing by CAC. Offenders are liable for damages. All rights, including but not limited to all proprietary rights in relation to patents, utility models and/ or other industrial property rights, are reserved. 1 Introduction Stack heights will be calculated according to the German First General Administrative Regulation Pertaining the Federal Immission Control Act, The standard is the basis for permitting of plants with relevant emissions to the atmosphere. 2 Data The stack height calculation is a standardized reverse dispersion calculation. The input data are stack parameters, flue gas quantity and conditions and concentrations of relevant air pollutants. To account for the different relevance of the individual air pollutants, the total flow Q of the air pollutants is devided by a factor S that is to be taken from TA Luft. The air pollutant with the largest Q/S value governs the stack height. According to TA Luft the two individual stacks have to be considered as one stack because of their distance (< 1.4 stack height). 3 Results The minimum stack height according to TA Luft is 15 m. Code Project No Document No Sheet Revision EDV-Ident-Nr. X:\38820x41\2009\09_093_Elektrolyse Turkmenistan_SOJITZ\VT\07_Umweltstudie\stack height calc_draft.doc Formblatt CFA 1500E Ausgabe: 02/05 Rev.:01

70 Any exploitation and/ or other utilization, including but not limited to reproduction, dissemination and/ or distribution of this document and its contents are strictly prohibited unless expressly authorized in writing by CAC. Offenders are liable for damages. All rights, including but not limited to all proprietary rights in relation to patents, utility models and/ or other industrial property rights, are reserved. Emission source A-01: Gas turbine unit flue gas flow (R) m³/h flue gas temperature (t) C 180 stack diameter (d) m 2.0 air pollutant emission flow rate Q kg/h S factor Annex 7 TA Luft NOx 20 0, stack height 10 Q/S kg/h Code Project No Document No Sheet Revision EDV-Ident-Nr. X:\38820x41\2009\09_093_Elektrolyse Turkmenistan_SOJITZ\VT\07_Umweltstudie\stack height calc_draft.doc Formblatt CFA 1500E Ausgabe: 02/05 Rev.:01

71 CHLORINE 0126 April 2000 CAS No: RTECS No: FO UN No: 1017 EC No: (cylinder) Cl 2 Molecular mass: 70.9 TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/SYMPTOMS PREVENTION FIRST AID/FIRE FIGHTING FIRE Not combustible but enhances combustion of other substances. Many reactions may cause fire or explosion. NO contact with combustibles, acetylene, ethylene, hydrogen, ammonia and finely divided metals. In case of fire in the surroundings: use appropriate extinguishing media. EXPLOSION Risk of fire and explosion on contact with combustible substances, ammonia and finely divided metals. In case of fire: keep cylinder cool by spraying with water but NO direct contact with water. EXPOSURE AVOID ALL CONTACT! IN ALL CASES CONSULT A DOCTOR! Inhalation Corrosive. Burning sensation. Shortness of breath. Cough. Headache. Nausea. Dizziness. Laboured breathing. Sore throat. Symptoms may be delayed (see Notes). Breathing protection. Closed system and ventilation. Fresh air, rest. Half-upright position. Artificial respiration may be needed. Refer for medical attention. Skin ON CONTACT WITH LIQUID: FROSTBITE. Corrosive. Skin burns. Pain. Cold-insulating gloves. Protective clothing. First rinse with plenty of water, then remove contaminated clothes and rinse again. Refer for medical attention. Eyes Corrosive. Pain. Blurred vision. Severe deep burns. Safety goggles or eye protection in combination with breathing protection. First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then take to a doctor. Ingestion SPILLAGE DISPOSAL Evacuate danger area! Consult an expert! Ventilation. NEVER direct water jet on liquid. Remove gas with fine water spray. Personal protection: complete protective clothing including self-contained breathing apparatus. Do NOT let this chemical enter the environment. PACKAGING & LABELLING T Symbol N Symbol R: 23-36/37/38-50 S: (1/2-) UN Hazard Class: 2.3 UN Subsidiary Risks: 8 Special insulated cylinder. Marine pollutant. EMERGENCY RESPONSE SAFE STORAGE Transport Emergency Card: TEC (R)-20S1017 NFPA Code: H 4; F 0; R 0; OX Separated from strong bases, combustible and reducing substances. Cool. Dry. Keep in a well-ventilated room. IPCS International Programme on Chemical Safety Prepared in the context of cooperation between the International Programme on Chemical Safety and the European Commission IPCS 2005 SEE IMPORTANT INFORMATION ON THE BACK.

72 0126 CHLORINE IMPORTANT DATA Physical State; Appearance GREENISH-YELLOW GAS, WITH PUNGENT ODOUR. Physical dangers The gas is heavier than air. Chemical dangers The solution in water is a strong acid, it reacts violently with bases and is corrosive. Reacts violently with many organic compounds, ammonia, hydrogen and finely divided metals causing fire and explosion hazard. Attacks many metals in presence of water. Attacks plastic, rubber and coatings. Occupational exposure limits TLV: 0.5 ppm as TWA; 1 ppm as STEL; A4 (not classifiable as a human carcinogen); (ACGIH 2004). MAK: 0.5 ppm, 1.5 mg/m 3 ; Peak limitation category: I(1); Pregnancy risk group: C; (DFG 2004). Routes of exposure The substance can be absorbed into the body by inhalation. Inhalation risk A harmful concentration of this gas in the air will be reached very quickly on loss of containment. Effects of short-term exposure Tear drawing. The substance is corrosive to the eyes, the skin and the respiratory tract. Inhalation of gas may cause pneumonitis and lung oedema, resulting in reactive airways dysfunction syndrome (RADS) (see Notes). Rapid evaporation of the liquid may cause frostbite. Exposure far above the OEL may result in death. The effects may be delayed. Medical observation is indicated. Effects of long-term or repeated exposure The substance may have effects on the lungs, resulting in chronic bronchitis. The substance may have effects on the teeth, resulting in erosion. PHYSICAL PROPERTIES Boiling point: -34/C Melting point: -101/C Relative density (water = 1): 1.4 at 20/C, 6.86 atm (liquid) Solubility in water, g/100 ml at 20/C: 0.7 Vapour pressure, kpa at 20/C: 673 Relative vapour density (air = 1): 2.5 ENVIRONMENTAL DATA The substance is very toxic to aquatic organisms. NOTES The symptoms of lung oedema often do not become manifest until a few hours have passed and they are aggravated by physical effort. Rest and medical observation are therefore essential. Immediate administration of an appropriate inhalation therapy by a doctor or a person authorized by him/her, should be considered. The odour warning when the exposure limit value is exceeded is insufficient. Do NOT use in the vicinity of a fire or a hot surface, or during welding. Do NOT spray water on leaking cylinder (to prevent corrosion of cylinder). Turn leaking cylinder with the leak up to prevent escape of gas in liquid state. Card has been partly updated in April See sections Occupational Exposure Limits, EU classification, Emergency Response. ADDITIONAL INFORMATION LEGAL NOTICE Neither the EC nor the IPCS nor any person acting on behalf of the EC or the IPCS is responsible IPCS 2005

73 SODIUM HYPOCHLORITE (SOLUTION, ACTIVE CHLORINE >10%) 1119 October 1999 CAS No: RTECS No: NH UN No: 1791 EC No: Sodium oxychloride Sodium chloride oxide NaClO Molecular mass: 74.4 TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/SYMPTOMS PREVENTION FIRST AID/FIRE FIGHTING FIRE EXPLOSION Not combustible. Gives off irritating or toxic fumes (or gases) in a fire. Powder, water spray, foam, carbon dioxide. In case of fire: keep drums, etc., cool by spraying with water. EXPOSURE STRICT HYGIENE! Inhalation Burning sensation. Cough. Laboured breathing. Shortness of breath. Sore throat. Symptoms may be delayed (see Notes). Ventilation, local exhaust, or breathing protection. Fresh air, rest. Half-upright position. Refer for medical attention. Skin Redness. Skin burns. Pain. Blisters. Protective gloves. Protective clothing. First rinse with plenty of water, then remove contaminated clothes and rinse again. Refer for medical attention. Eyes Redness. Pain. Severe deep burns. Face shield, or eye protection in combination with breathing protection. First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then take to a doctor. Ingestion Abdominal pain. Burning sensation. Shock or collapse. Unconsciousness. Vomiting. Do not eat, drink, or smoke during work. Rinse mouth. Do NOT induce vomiting. Refer for medical attention. SPILLAGE DISPOSAL Ventilation. Collect leaking and spilled liquid in sealable containers as far as possible. Then wash away with plenty of water. Do NOT absorb in saw-dust or other combustible absorbents. Personal protection: complete protective clothing including self-contained breathing apparatus. Do NOT let this chemical enter the environment. PACKAGING & LABELLING C Symbol N Symbol R: S: (1/2-) Note: B UN Hazard Class: 8 UN Pack Group: II, III Do not transport with food and feedstuffs. EMERGENCY RESPONSE SAFE STORAGE Transport Emergency Card: TEC (R)-80S1791 Separated from combustible and reducing substances, acids, food and feedstuffs. See Chemical Dangers. Cool. Keep in the dark. Well closed. IPCS International Programme on Chemical Safety Prepared in the context of cooperation between the International Programme on Chemical Safety and the European Commission IPCS 2004 SEE IMPORTANT INFORMATION ON THE BACK.

74 1119 SODIUM HYPOCHLORITE (SOLUTION, ACTIVE CHLORINE >10%) IMPORTANT DATA Physical State; Appearance CLEAR, YELLOWISH SOLUTION, WITH CHARACTERISTIC ODOUR. Chemical dangers The substance decomposes on heating, on contact with acids and under influence of light producing toxic and corrosive gases including chlorine (see ICSC 0126). The substance is a strong oxidant and reacts violently with combustible and reducing materials, causing fire and explosion hazard. The solution in water is a strong base, it reacts violently with acid and is corrosive. Attacks many metals. Occupational exposure limits TLV not established. Routes of exposure The substance can be absorbed into the body by inhalation of its aerosol and by ingestion. Inhalation risk No indication can be given about the rate in which a harmful concentration in the air is reached on evaporation of this substance at 20/C. Effects of short-term exposure The substance is corrosive to the eyes, the skin and the respiratory tract. Corrosive on ingestion. Inhalation of aerosol may cause lung oedema (see Notes). The effects may be delayed. Medical observation is indicated. Effects of long-term or repeated exposure Repeated or prolonged contact may cause skin sensitization. Relative density (water = 1): 1.21 (14% aqueous solution) PHYSICAL PROPERTIES The substance is toxic to aquatic organisms. ENVIRONMENTAL DATA NOTES Household bleaches usually contain about 5% sodium hypochlorite (about ph11, irritant), and more concentrated bleaches contain 10-15% sodium hypochlorite (about ph13, corrosive). The symptoms of lung oedema often do not become manifest until a few hours have passed and they are aggravated by physical effort. Rest and medical observation is therefore essential. Immediate administration of an appropriate inhalation therapy by a doctor or a person authorized by him/her, should be considered. Rinse contaminated clothes (fire hazard) with plenty of water. Chloros, Chlorox, Clorox, Deosan, Javex, Klorocin, Parozone and Purin B are trade names. Also consult ICSC #0482 (Sodium hypochlorite, active chlorine <10%). Card has been partly updated in October See sections Occupational Exposure Limits, EU classification, Emergency Response. ADDITIONAL INFORMATION LEGAL NOTICE Neither the EC nor the IPCS nor any person acting on behalf of the EC or the IPCS is responsible IPCS 2004

75 HYDROGEN CHLORIDE 0163 April 2000 CAS No: RTECS No: MW UN No: 1050 EC No: Anhydrous hydrogen chloride Hydrochloric acid, anhydrous (cylinder) HCl Molecular mass: 36.5 TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/SYMPTOMS PREVENTION FIRST AID/FIRE FIGHTING FIRE Not combustible. In case of fire in the surroundings: use appropriate extinguishing media. EXPLOSION In case of fire: keep cylinder cool by spraying with water. EXPOSURE AVOID ALL CONTACT! IN ALL CASES CONSULT A DOCTOR! Inhalation Corrosive. Burning sensation. Cough. Laboured breathing. Shortness of breath. Sore throat. Symptoms may be delayed (see Notes). Ventilation, local exhaust, or breathing protection. Fresh air, rest. Half-upright position. Artificial respiration may be needed. Refer for medical attention. Skin ON CONTACT WITH LIQUID: FROSTBITE. Corrosive. Serious skin burns. Pain. Cold-insulating gloves. Protective clothing. First rinse with plenty of water, then remove contaminated clothes and rinse again. Refer for medical attention. Eyes Corrosive. Pain. Blurred vision. Severe deep burns. Safety goggles or eye protection in combination with breathing protection. First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then take to a doctor. Ingestion SPILLAGE DISPOSAL Evacuate danger area! Consult an expert! Ventilation. Remove gas with fine water spray. Personal protection: complete protective clothing including self-contained breathing apparatus. PACKAGING & LABELLING T Symbol C Symbol R: S: (1/2-) /37/39-45 UN Hazard Class: 2.3 UN Subsidiary Risks: 8 EMERGENCY RESPONSE Transport Emergency Card: TEC (R)-20S1050 NFPA Code: H 3; F 0; R 1 SAFE STORAGE Separated from combustible and reducing substances, strong oxidants, strong bases, metals. Keep in a well-ventilated room. Cool. Dry. IPCS International Programme on Chemical Safety Prepared in the context of cooperation between the International Programme on Chemical Safety and the European Commission IPCS 2005 SEE IMPORTANT INFORMATION ON THE BACK.