Small Waste Water Treatment Plants WWTP. Technical aspects and cost estimation of pilot plants. Indira Sulejmanagić Sanja Bosiljčić Pandur

Transcription

1 Small Waste Water Treatment Plants WWTP Technical aspects and cost estimation of pilot plants Indira Sulejmanagić Sanja Bosiljčić Pandur

2 WWTP and Sewerage System In BiH, inadequate attention was given to protection of waters in the past. This situation was additionally aggravated by infrastructural damages, that occurred due to war activities (during the period ), and inappropriate repair and maintenance services, caused by difficult financial situation of public utility companies. Percentage of population connected to the sewerage systems in urban areas (cities and settlements > 10,000 inhabitants) is about 56%. Generally, the smaller, rural settlements have no sewerage system. Some of them, that have a sewerage system for collection of waste waters, usually are without the waste water treatment. That means that the untreated effluent is discharged into recipients, what present a serous threats against for human health.

3 WWTP and Sewerage System The key problems of waste water treatment plants / WWTP in the whole Bosnia and Herzegovina are as follows: Most of the planned wastewater treatment plants are not built, neither were reconstructed; The existing WWTP are under-maintained (due to low water price - insufficient for functionality costs of a simple water system), and they lose their planned efficacy, quite fast; Even in towns and settlements that have a WWTP, insufficient inhabitants are connected to facilities.

4 WWTP and Sewerage System Thanks to international organizations and programs funds (World Bank, KfW, EIB, EBRD, IPA, SIDA), as well as local participation of municipalities and financing from Environmental Protection Fund FB&H, current construction level / situation of WWTP is improved. So far, a number of facilities is built or reconstructed, which have already been put into operation, such as: Živinice PE, Srebrenik PE, Bijeljina PE, Trebinje PE, Bileća PE, Ljubuški PE, Čitluk PE, Žepče PE, Trnovo PE, Odžak PE. Plants in Sarajevo 600,000 PE and Konjic 5,000 PE are in test operation phase. The construction of the facilities for the city of Mostar and Bihac (100,000 and 55,000 PE) is in implementation, and WWTP for settlements Tomislavgrad and Siroki Brijeg (each 10,000 PE) are in preparation phase (for the works).

5 Definition and Classification The result of wastewater treatment is the removal of harmful substances from the water and thus is achieved / provided a certain required sanitary, chemical, ecological and aesthetic quality of natural recipients. Facilities by size: for large and medium cities and small towns and villages. Plant size for smaller towns and villages: up to 50 PE and between 50 and 5,000 PE (in rare cases up to 10,000 PE).

6 Technological Scheme The usual purification technology / waste water treatment includes: The level of treatment Pre-treatment 1. Stage primary sludge 2. Stage or biological treatment secondary sludge Isolated substances Waste from grids, sand, gravel, fat Sludge treatment Organic substances 3. Stage N and P Disinfection Pathogenic organisms Discharge of treated water

7 Investment Costs - Conventional Plant Investment Cost WWTP /PE With a receiving station for waste water from septic tanks Without a receiving station for waste water from septic tanks Size (PE)

8 Small Settlements In smaller settlements there is the problem of lack of professional staff and limited financial resources The advantage of plants wherein the: Energy consumption is small or a zero Operation and maintenance are simple The efficiency and continuous work are good and at extremely high variations of flow and level of influent's load Small or no sludge production and its simple treatment The smaller WWTP that meet these requirements are classified as so-called. unconventional

9 Study of unconventional technologies and Pilot projects GEF - Project of water quality protection Feasibility study on the implementation of natural treatment procedures of urban waste water of small towns and settlements on territory of Bosnia and Herzegovina The objectives of this study were: 1. to develop the proposals for improving wastewater management through the implementation of NTC" - technology 2. to identify the optimal strategies for the need "NCT" - technology wastewater treatment with regard to natural, social, cultural, economic, institutional and climatic aspects and other features 3. to create a long-term and short-term investment plans for waste water treatment plants, based on the application of "NCT" - technology 4. to identify the pilot projects of waste water treatment with a low cost / low energy consumption in various typical areas of Bosnia and Herzegovina As pilot projects, the following settlements were selected: Velagići+Hadžići (Applied Technology: Hybrid artificial wetlands with the removal of nutrients), Municipality of Ključ, FB&H Grborezi (Applied Technology: Hybrid artificial wetlands with the removal of nutrients), Municipality of Livno, FB&H Orahova (Applied Technology: Trickling filter), Municipality of Gradiška, RS

10 Investment Costs 700 /PE Investment costs per PE for some types of small plants 600 /PE 500 /PE 400 /PE 300 /PE 200 /PE The stabilizing wetlands The artificial wetlands Hybrid artificial wetlands Trickling filters Rotating biological contactors 100 /PE 0 /PE 0 PE PE PE PE PE PE Plant size

11 Operation and Maintenance Costs Annual operation and maintenance costs / PE 700 /PE 600 /PE 500 /PE 400 /PE 300 /PE 200 /PE The stabilizing wetlands The artificial wetlands Hybrid artificial wetlands Trinkling filters Rotating biological contactors 100 /PE 0 /PE 0 PE PE PE PE PE PE Plant size

12 Preliminary design of WWTP for settlement Grborezi, Municipality of Livno GENERAL: Responsible persons and residents were very interested for the project The proposed settlement is located in a karst area, Livno field, that has a size of 30,000 hectares, and is one of the largest in Europe Sensitive area - the area of karst The water from the Livno field is used in the Republic of Croatia for drinking Residents of the settlement Grborezi participated with 50% of funds in the investment for construction of sewage system Climate: mountain The whole settlement Grborezi counts of 800 residents The settlement has no industry SEWERAGE SYSTEM: Two phases of construction of the sewage system have been completed, that includes the main collector and several secondary collectors construction The sewage system is separate. The main collector (3,000 m, DN 300) is currently finishing in a septic tank Recipient is the irrigation canal, that is over the year mostly dry The existing sewage system is designed for the 1200 PE LOCATION OF WWTP: There is a potential location for the wastewater treatment plant in the field called Podovi The site is in private ownership, but according to information received from inhabitants solving this issue should not be a problem because the owner is willing to cooperate The high level of ground water (approx. 80 cm in winter), filling of the terrain is necessary

13 Preliminary design of WWTP for settlement Grborezi, Municipality of Livno Taking into consideration the local conditions for settlement Grborezi, the following technological scheme has been chosen: Mechanical treatment: screening, gravity longitudinal sand tank - grid chamber and septic tank reconstructed in to the primary sedimentation tank; Chemical treatment: flocculation to eliminate the total phosphorus; Biological treatment: hybrid artificial wetlands, stabilization tank; Sludge: Primary sludge form the primary sedimentation tanks is taken into silo/tank. For further treatment of sludge is planned that the sludge should be taken on fields used for topsoilin;. Because of the required conditions of effluent quality at the outflow, the proposed solution involves tertiary treatment purification. Predložena lokacija budućeg postrojenja The proposed location of the plant Rešetka Screen Pjeskolov Grid chamber VSSF VSSF Effluent Efluent W3 Hybrid artificial wetlands Hybrid artificial wetlands

14 Preliminary design of WWTP for settlement Grborezi, Municipality of Livno INVESTMENT COSTS Investment costs are taken from the priced bill of quantities and in total are estimated at 327, Note: The total value of the investment costs does not include costs of design documents of a higher level, as well as VAT. OPERATION AND MAINTENANCE COSTS The operation costs include the costs of energy consumption, costs of chemicals, costs of waste disposal from the grid and of sludge, as well as personnel costs (for plant maintenance) and the same are assessed on an annual basis to / year.

15 Preliminary design of WWTP for settlement Velagići-Hadžići, Municipality of Ključ GENERAL: Velagići / Hadžići is the second largest settlement in the municipality of Ključ with about 2,350 inhabitants Climate: medium continental The proposed settlements are in the area of karst WWTP Velagići+Hadžići: PE Sewerage systems of these settlements are designed as two separate units and in the current project proposes there are two smaller plants for wastewater treatment The population is mainly engaged in agriculture, and there is less wood industry SEWERAGE SYSTEM: In LC Velagići there are two separate, newly constructed sewage systems, because area of local community is divided into two basins, streams Točine and Vojića potok. Both systems are designed for a total of about 3,500 PE, up to the end of the planning period (planning period is 25 years). The recipient is stream Točine, that disappears underground. It is assumed that the water appears again, at sources along the river Sana. LOCATION OF WWTP: The municipality has offered a potential location for NCT plant. It is located upstream of the abyss, in the valley of stream Točina. Outflow / discharge in a sensitive area (abyss)

16 Preliminary design of WWTP for settlement Velagići-Hadžići, Municipality of Ključ Taking into consideration the local conditions for settlements Velagići and Hadžići, the following technological scheme has been chosen: Mechanical treatment: inlet pumping station, screening, aerated grid chamber and Imhoff tank Chemical treatment: flocculation to eliminate the total phosphorus; Biological treatment: hybrid artificial wetlands, stabilization tank; Sludge: Primary sludge form the Imhoff tank, is further processed in the same in the part representing digestion compartment. From Digestion compartment, sludge is discharged on fields used for topsoiling of sludge. Due to the required outflow effluent quality requirements, the proposed solution involves tertiary treatment of purification. Predložena lokacija budućeg postrojenja The proposed location of the plant Rešetka Pjeskolov VSSF VSSF Efluent Screen Grid chamber Effluent W3 Hybrid artificial wetlands Hybrid artificial wetlands

17 Preliminary design of WWTP for settlement Velagići-Hadžići, Municipality of Ključ INVESTMENT COSTS Investment costs are taken from the priced bill of quantities and in total are estimated at ,75. Note: The total value of the investment costs does not include costs of design documents of a higher level, as well as VAT. OPERATION AND MAINTENANCE COSTS The operation costs include the costs of energy consumption, costs of chemicals, costs of waste disposal from the grid and of sludge, as well as personnel costs (for plant maintenance) and the same are assessed on an annual basis to /year.

18 Financial needs for potential NCT in selected targeted areas According to the ranking (rating list) of priorities, through NCT study were identified 670 potential non-conventional plants, with a capacity between 500 and 10,000 PE. Total amount of investment required for the potential NCT in B&H is about 530 mil.km (270 mil. of EUR). Annual operating and maintenance costs, for all identified NCT plants, are estimated at 43 million. KM (22 mil. of EUR).

19 COOPERATION "Ecoremediation for protection of the environment and development of the Una-Sana Canton" is a project worth 391, KM, that is implemented by the Center for International Cooperation in Developing - CMRS, of Republic of Slovenia and the Environmental Protection Fund of FB&H. The result of the project is installed pilot device of this type, within the area of the Biotechnical Faculty of Bihać.

20 Conclusions There is a Study about the applicability of NTC plants, and Bosnia and Herzegovina has the basic planning document, and within the same, the guidelines for solving of wastewater collection and treatment problems in smaller settlements; The financial situation in B&H, especially in small rural settlements is not favorable / good, thus investment in projects of waste water treatment, in terms of survival for population in smaller towns, does not present top of priorities of smaller communities; From the aspect of basic living conditions insurance, and according to experience in the field, it is concluded that residents and local communities are aware of the importance and needs for projects implementation, and for the same they expressed significant interest.

21 Conclusions Solutions: Technical assistance provide by foreign consultants Obtaining financial resources through EU funds and pre-accession financing programs Establishment of a new, suitable financial mechanisms for projects financing, with support of EU partners

22 Small Waste Water Treatment Plants WWTP Technical aspects and cost estimation of pilot plants Indira Sulejmanagić Sanja Bosiljčić Pandur

23