Central Wastewater Treatment Plant energy efficient operation and experiences

Átírás

1 H-1134 Budapest, Váci út Adress: 1325 Bp., Pf.: 355. Phone: Fax: Central Wastewater Treatment Plant energy efficient operation and experiences 1 EWA SPRING DAYS 2015 Conference Budapest Water Conference Budapest,

2 Agenda 1. Background of the Budapest Central Wastewater Treatment Plant (BCWWTP) 2. Plant description Main characteristics 3. Datas from the operation 2

3 Waste and rainwater catching areas IV III II XII I V XI XIII XV Észak-Pest m 3 /day (1980) XIV XVI VI VII VIII IX XIX Dél-Pest m 3 /day XVIII XX CSEPEL m 3 /day XXI XXII m 3 /day (1966) XXIII (2010) XVII 3

4 LIVING DANUBE Project Basic Data of the BCWWTP: Capacity: 1,6 M population equivalent Wastewater quantity: m 3 /day Max. wastewater quantity: m 3 /day (10.4m 3 /s) ~ 95% of yearly received wastewater biologically treated Average daily received wastewater quantity in 2014: m 3 4

5 Main characteristics Covered and ventilated process structures Extracted air treated by biological and chemical odour treatment units Architecture and Landscaping fits to surrounding area (70% of the plant is GREEN) Biogas used for energy production and heating (~60% recovery of electricity consumption) 5

6 6 Treament flow chart Autosampling ponit BY PASS Grit Flow meters FeCl m 3 /h m 3 /h Kelenföld Pumping station Pumping station FINE SCREENS (3 mm) 6+2 units SEDIPAC 3D Grit removal, fat flotation, Primary sedimentation) 7 (+1 reserve) units BIOLOGICAL TREATMENT (pre-anoxic, anaerobic, aerobic/anoxic zone) 17 (+1 reserve) units Ferencvárosrosrosros m 3 /h m 3 /h m 3 /h BIOLOGICAL SLUDGE THICKENER Screenings Grit Greace Sludge Sludge, NO3 Recirculation Outlet to Danube N30 P2 Conveyor 2 + Compactor 2 Grit classifier 2 db Greace evacuation Deposition Deposition Polymerisation 2 units Rain Water CLARIFIERS Thickener Sludge 17 (+1 reserve) units (4 Units) NITROGEN FeCl 3 Poly GRIT REMOVAL 3 Units REMOVAL (DEMON) (2 Units) GRAVITATY THICKENERS 2 (+1 reserve) DRAINING TABLES 5 (+1 reserve) MIXED SLUDGE TANK 1 tank PASTEURISATION 2 (+1 reserve) lines 1 line = 3 tanks TERMOFIL ANAEROBIC DIGESTERS 3 reactors DIGESTED SLUDGE TANK CENTRIFUGE 2 (+1 reserve) DEWATERED SLUDGE TANKS 4 TANKS COGENERATION 2 (+1 reserve) lines Recultivation (Mun) Biogás holder 2 Ferric-chloride dosing Ferric-chloride dosing POLYMERISATION 2 units

7 Mechanical treatment 7

8 Primary Sedimentation SEDIPAC 3D (8) Compact device Grit removal Grease removal Lamellar settling TSS removal efficiency 65 70% 8

9 Biological treatment 9

10 Biological treatment Pre-anoxic Anaerobic Anoxic/Aerobic Secondary Clarifier Pre-anoxic Secondary Clarifier Anaerobic Anoxic/Aerobic 10

11 Biological reactor (18) Aerobic/Anoxic zone Anaerobic zone Pre-anoxic zone 11

12 Inlet Outlet values Inlet: 295,2 mg/l Outlet: 0,9 mg/l Inlet: 328,7 mg/l Outlet: 0,15 mg/l 12

13 Inlet Outlet values Inlet: 513,9 mg/l Outlet: 20,5 mg/l Inlet: 565,7 mg/l Outlet: 14,7 mg/l 13

14 Inlet Outlet values Inlet: 268,9 mg/l Outlet: 5,6 mg/l Inlet: 290,7 mg/l Outlet: 4,3 mg/l 14

15 Inlet Outlet values Inlet: 53,2 mg/l Outlet: 11,6 mg/l NO 3 recirkulation and DEMON start up Inlet: 58 mg/l Outlet: 10,2 mg/l Trial period 3rd phase 15

16 Inlet Outlet values Inlet: 37,8 mg/l Outlet: 1,8 mg/l NO 3 recirkulation and DEMON start up Inlet: 41,3 mg/l Outlet: 1,5 mg/l 16

17 Inlet Outlet values Inlet: 6,66 mg/l Outlet: 1,9 mg/l Inlet: 7,16 mg/l Outlet: 1,05 mg/l 17

18 Treated water characteristics Parameters (mg/l) Water Operating Permit Average COD 125 < 33 BOD 5 25 < 10 TSS 35 4,3 TN 30* 10,2 TP 2* 1,05 Raw Water Flow Rate (m 3 /d) *From the end of 2013, TN < 10 mg/l, TP < 1 mg/l 18

19 Biological sludge VS% VS: 72,2 % Aerated sludge age: 7,3 days VS: 70,4 % Aerated sludge age: 7,1 days 19

20 Sludge line 20

21 Thickening Primery Sludge Biological Sludge Pressing zone Moving scraper system Thickened sludge evacuation Continuous belt washing zone Filtrate and washing water collection pan Sludge feeding Adjustable feet Filtrate withdrawal Concentration: g/l g/l Daily thickened volume: 900 m 3 /d 520 m 3 /d VS content: 75% 76% 21

22 Sludge treatment Digestion system (3 x 6050 m 3 ) Thermophilic anaerobic digestion at 55ºC VS removal: 50% Minimum SRT 12 days Daily feed:1500 m 3 /d DIGESTERS 22

23 Digesters sludge Vs load, biogasproduction 23

24 Digesters, Feeding-VFA-TAC 24

25 Digesters SRT 25

26 Biogas production VS kg destroyed 26

27 Primery-, Biosludge ratio biogasproduction 1,03 1,02 1,03 1,08 1,07 1,11 27

28 Cogeneration Biogas holders Double membrane system Capacity 2x3500 m 3 Pressure 25 mbar Increased to 120 mbar before the engines Activated carbon filter remove: siloxanes H 2 S <120ppm 28

29 Sludge dewatering Centrifuges (3 units + 1) DS (average) g/l: Incoming sludge: 0,2 Primary sludge: 26 Biological sludge: Thickened sludge: Digested sludge: 30 Dewatered sludge: min. 270 Sludge quantity (average, 2014): Primary sludge: 2900 m 3 /d Biological sludge: 3200 m 3 /d Mixed sludge: 1440 m 3 /d Dewatered sludge : 160 t/d 29

30 Biogas engine - Cogeneration 2+1 gas engine 1,4MW/unit ~ Nm3/d biogas ~ kwh/d energy 30 The waste heat is used to heat the sludge during the digestion process The cogeneration insures 60% self-efficiency

31 Biogas and electricity values Biogas: Nm 3 /d Electr.: kwh/d 31

32 Self - efficiency 2013: without biologie ventilation 69% 2014: without biologie ventilation 65% Self efficiency kwh/treated water ,2% 0, ,2% 0, ,5% 0, ,1% 0, % 0,

33 Sludge dewatering 10,6 kg/t 11 kg/t 33

34 Future projects Archimedes turbine Heat pump Cell disruption 34

35 Thank You for the Attention Bence Márialigeti Sewage Operations Director WATERWORKS OF BUDAPEST I FŐVÁROSI VÍZMŰVEK ZRT. Budapest XIII., Váci út I Postal address: H-1325 Budapest, Pf. 355 TEL: FAX: MOBILE: bence.marialigeti@vizmuvek.hu WEB: László Váci HEAD OF SEWAGE OPERATIONS DEPARTMENT WATERWORKS OF BUDAPEST I FŐVÁROSI VÍZMŰVEK ZRT. Budapest XIII., Váci út I Postal address: H-1325 Budapest, Pf. 355 TEL: FAX: MOBILE: laszlo.vaci@vizmuvek.hu WEB: 35