HELCOM Programme Implementation Task Force (HELCOM PITF) PITF 18/ th Meeting 6.2/5. Tallinn, Estonia 30 October November 2001

Transcription

1 HELSINKI COMMISSION - Baltic Marine Environment Protection Commission HELCOM Programme Implementation Task Force (HELCOM PITF) PITF 18/ th Meeting 6.2/5 Tallinn, Estonia 30 October November 2001 Agenda Item 6 INVESTMENT ACTIVITIES / POINT SOURCE POLLUTION AND NON-POINT SOURCE POLLUTION 6.2 Possible changes in the List of Hot Spots Application for deletion of Hot Spot No. 79 Submitted by Poland Information on the Kapusciska wastewater treatment plant in Bydgoszcz. The Meeting is invited to consider the information and to decide on possible deletion of this Hot Spot from the JCP List. Note by the Secretariat: FOR REASONS OF ECONOMY THE DELEGATES ARE KINDLY REQUESTED TO BRING THEIR OWN COPIES OF THE DOCUMENTS TO THE MEETING

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3 Proposal for deletion of the JCP Hot Spot No. 79 Kapusciska Wastewater Treatment Plant in Bydgoszcz Submitted by Poland I. The characteristic of the Kapusciska WWTP The Kapusciska Wastewater Treatment Plant has been designed as a municipal and industrial plant, processing: Smunicipal wastewater from the south-east part of the Bydgoszcz City; Sindustrial wastewater from the chemical industry (organic wastewater) after preliminary neutralization at the Zachem Chemical Plant in Bydgoszcz; Smunicipal wastewater from the Solec Kujawski City. The contract for the WWTP construction has been signed in 20 June The designed WWTP capacity is m 3 /day. Chemical wastewater constitutes 35 % of the inflow. The contract assures the achievement of all limit values set in the water permit. The investment included: Sdevelopment of the sewage system; Smechanical-biological wastewater treatment plant with additional nutrients removal. The technological scheme has been designed on the basis of technological research which recommended the separate treatment of municipal and industrial wastewater streams, which should be mixed just before the discharge point to the receiving body Vistula River. The aims of the investment were: Sto restore the Brda River and achieve at least the II class of water purity downstream the discharge point; Sto improve the water quality of the part of the Vistula River between Bydgoszcz and Gdansk; Sto protect the Baltic Sea coastal waters by reduction of pollution discharged with the Vistula River. The technological start-up lasted from 5 March 2001 till 28 September

4 The average amount of inflowing wastewater is: Industrial waste water Municipal wastewater from Bydgoszcz Municipal wastewater from Kujawiec Solski Total: m 3 / day m 3 /day m 3 /day m 3 /day To increase the amount of waste water processed by the WWTP to designed capacity, sewage system in Bydgoszcz is being developed. II. Technology of the wastewater treatment, the quality of the effluent, fulfilment of relevant HELCOM Recommendations. Municipal wastewater treatment. 1. Supply of municipal wastewater to the expansion chamber; 2. Filtering on the grates; 3. Sand separation and grease flotation in the aerated desanders; grease is pumped to the sludge processing pair; 4. Sedimentation of the rude suspension contained in the sludge on the primary settling tanks; removal of the preliminary deposit to the gravitational thickeners and hydrolysis to volatile fatty acids (VFAs; the source of the easily biodegradable organic carbon improving the efficiency of biological nutrients removal); pumping of the VFAs together with the sludge and over-sludge water upstream to preliminary settling tanks; 5. Biological treatment on the activated sludge (anaerobic, anoxic, aerobic and predenitrification zones in each bioreactor); 6. Sedimentation on secondary settling tanks; separation of activated sludge from the treated wastewater; sludge is recirculated to the biological reactors or pumped to the sludge fermentation pair; 7. Flow of treated waste water to the canal and mixing with treated industrial waste water; discharge to the recipient. 2

5 Industrial wastewater treatment 1. Neutralisation of influent reaction to ph from 6.5 to 9.0. Collection of wastewater in bedding tank, than pumping to the sorption chamber; 2. Biological treatment on activated sludge (aeration zone); 3. Secondary sedimentation; 4. Discharge to the recipient. Concentration of pollution in raw wastewater and treated waste water Parameter Unit Untreated wastewater Treated wastewater Reduction rate [%] HELCOM Recommendations 9/2 and 16/9 BOD 5 mg O 2 /l mg/l and 90% reduction COD mg O 2 /l Suspended solids Total Nitrogen Ammonia Nitrogen mg/l mg N/l mg/l or % reduction mg N- NH4 /l Total P mg P/l mg/l III. Sludge treatment, amount and quality of sludge. Sludge management 1. Preliminary sludge is directed to closed fermentation chambers. Surplus active sludge is prethickened before fermentation. 2. Fermented sludge is degassed and dewatered on mechanical centrifuges. 3. Biogas is treated and used as a fuel for plant s heating 4. Dewatered sludge (30 tonnes/day) is used for post-industrial land reclamation. At a same time, further investments aimed at other possibilities of sludge management and use are developed. 3

6 Sludge quality Element/Parameter Unit Pb mg /kg d.m Cd mg /kg d.m Cr mg /kg d.m Cu mg /kg d.m Ni mg /kg d.m Zn mg /kg d.m Hg mg /kg d.m Organic substances % /kg d.m. 69 Mineral substances % /kg d.m. 31 Mg % /kg d.m. 0.3 Ca % /kg d.m. 0.7 P tot % /kg d.m. 0.2 N tot % /kg d.m. 0.7 Content of dry matter % /kg d.m. 25 ph 7.16 N NH4 % /kg d.m. 1.1 The sludge quality with regard to heavy metals is in accordance with the provisions of Council Directive 86/278/EEC of 12 June 1986 on the protection of the Environment, and in particular of the soils, when sewage sludge is used in agriculture, as well as national Executive Order of 11 August 1999 on the conditions to be met when sewage sludge is used for non-industrial purposes. IV. Environmental monitoring conducted by the WWTP The plants laboratory controls the quality of wastewater at the inlet and the outlet of the plant. Samples are take automatically in 24-hours regime. Basic parameters (N NO3, N NO2, N NH4 and P tot ) are measured on-line during the treatment process as well. System of piezometers installed around the plant enables the control of groundwater quality. The laboratory takes part in the PLC 4 Project. 4

7 V. Financing of investment The total cost of the investment amounts to thousand PLN (approx. : 43.5 mill EUR) Source mill PLN mill EUR the loan from the National Fund for Environmental Protection and Water Management the loan from the Provincial Fund for the Environmental Protection and Water Management commercial credit from the PeKaO S.A subsidy from the ECOFUND the subsidy from the Communal Fund for the Environmental Protection and Water Management own sources (shared by the plant s owners) TOTAL: Indirect investment costs related to the investment service, repayment of credits and loans interest and instalments (29.5 mill PLN, approx mill EUR) have been covered by the Kapusciska Water Company (operator of the plant) itself. 5