COGENERATION OF ELECTRICAL AND THERMAL ENERGY FROM BIOGAS IN WASTEWATER TREATMENT PLANTS THE CASE OF BRAZIL. Eduardo Pacheco Jordão, Dr. Eng.

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1 Universidade Federal do Rio de Janeiro Escola Politécnica, Depto. de Recursos Hídricos e Meio Ambiente VENICE, 2010 COGENERATION OF ELECTRICAL AND THERMAL ENERGY FROM BIOGAS IN WASTEWATER TREATMENT PLANTS THE CASE OF BRAZIL Eduardo Pacheco Jordão, Dr. Eng. VENICE, 2010

2 Brazil and Latin America

3 Brazil Area: 8,6 million km 2 Population: 187 million Water Supply: ~ 95% * Sewerage: ~ 51% * Wastewater treatment: ~ 35% ** * % of the urban population ** % of the sewer system = ~17% of the urban pop.

4 Sanitation in Brazil Population Total - % Urban - % Water Supply Sewerage Wastewater Treatment 34.6 * (*) = 17% of the urban pop., SNIS, 2008

5 Wealthy countries Infant Mortality Year 2010 Developing countries Very poor countries VENICE, Sweden Japan Italy Norway France UK USA Cuba Chile Argentina China Colombia Mexico Brazil Chade G.Bissau Mali Nigeria Angola

6 Health & Sanitation Year Infant Mortality in Brazil ,7 /1000 born, under 1 year old , ,9 Brazil should meet the millenium goal

7 Materials The Urban Challenge Food Energy Water Wastewater Emissions CO2 NOx SO2 Solid Wastes Chemicals

8 Materials The Urban Challenge Food Energy Water Chemicals Wastewater Emissions CO2 NOx SO2 Solid Wastes Recycle - Reuse Treat

9 Materials The Urban Challenge Food Energy Water Wastewater Emissions CO2 NOx SO2 Solid Wastes Chemicals Recycle - Reuse Treat Recover Energy

10 Challenge Wastewater Treatment Enormous advancement in wastewater technology in Brazil Economical processes for wastewater treatment have been well stablished There is a good Brazilian experience with new and applicable technology How experts, federal and state agencies are facing the question?

11 Investigation & Research Funding Water Utilities FINEP, a governmental organization, under Ministry of Science and Tecnlogy; Has been financing a special research program on wastewater treatment since 1996; specially on anaerobic processes; 15 universities form the research network

12 Wastewater Treatment Research Center, UFRJ VENICE, 2010

13 UASB = Upflow Anaerobic Sludge Blanket Reactor One of the new economical processes developed for WWTP.

14 UASB Influent Biogas acumulation Phase separator VENICE, 2010 UASB Effluent Influent flow pipes EDUARDO PACHE CO JORDÃO

15 UASB compact system, using a small surface area; practically no equipment in the anaerobic process, with low construction and operational costs; very low energy consumption; low excess sludge produced; INTENSE BIOGAS PRODUCTION.

16 UASB + Activated Sludge Activated Sludge effluent influent UASB Reactor Aeration tank Secondary clarifier Recirculation Digested sludge for drying Excess sludge

17 UASB Reactors + Postreatment Possibility of Energy Recovery from the Biogas produced

18 A new design Clarifiers + second. treat. UASB + secondary treat. PRIMARY CLARIFICATION SECOND. TREATM./ UASB SECOND. TREATM. SLUDGE CONDIT. CONDIT. & STABILIZ. STABILIZ. SLUDGE DEWAT. Sludge to Final Disposal / Reuse SLUDGE DEWATER. DEWATER. Sludge to Final Disposal / Reuse

19 UASB IN BRAZIL

20 S.Jorge WWTP Alm. Tamandaré 20,000 inhab. VENICE, 2010 EDUARDO PACHE CO JORDÃO

21 Cambuí WWTP - Campo Largo, 30,000 VENICE, 2010 EDUARDO PACHE CO JORDÃO

22 Barreto WWTP Niterói, 60,000 VENICE, 2010 EDUARDO PACHE CO JORDÃO

23 Rio das Ostras WWTP 150,000 VENICE, 2010

24 Sul WWTP Londrina, 225,000

25 Piçarrão WWTP Campinas, 250,000

26 Gama WWTP Brasília, 300,000 EDUARDO PACHE CO JORDÃO

27 Atuba Sul WWTP Curitiba - 580,000 VENICE, 2010 EDUARDO PACHE CO JORDÃO

28 Onça WWTP Belo Horizonte 1,500,000

29 Yes we can! We can afford adjusting our technology for our own conditions We can afford buiding cost-effective WWTP We can win the challenge of poverty, of public health, of water management, of environmental protection We can produce biosolids for agriculture We can recover energy from our WWTP We can manage a sustainable sanitation program

30 Burning gas x Energy recovery

31 Conversion of Volatile Solids into Methane Gas

32 Energy Recovery Gás Heat Power, kj/m 3 Propane (comercial) 45,800 Butane (comercial) 44,600 Natural gas 37,300 Methane 35,800 Digestion gas (*) 22,400 (*) For 65% methane in the biogas

33 Energy Recovery Heat power (biogas) = 22,400 kj/m 3 5 to 20 L gas/person.day (conv. plant) For a 200,000 people Conv. Plant (*): x 200,000 = 2,000 m 3 biogas/day 2,000 x 22,400 = 4.5 x 10 7 kj/d = 1.6 x kj/y = 4.6 x 10 6 kwh/y (*) with the maximum gas production

34 Energy consumption at the WWTP VENICE, 2010 Typical WWTP uses ~ 1,200 kwh/mg treated Aeration = 52% Solids processing =30% Influent pumping = 12% Internal recycle pumping = 3% Nutrient removal generally increases overall energy costs

35 Energy consumption at the WWTP 200,000 people X 40 gal/hab.d = 8 MGD = 2,920 MGY VENICE, 2010 Consumption Rate ~ 1,200 kwh/mg treated Energy Use~ 2920 x 1200 = 3.5 x 10 6 kwh/y Production, max.gas rate ~ 4.6 x 10 6 kwh/y Production, avg.gas rate ~ 2.3 x 10 6 kwh/y Production, min.gas rate ~ 1.2 x 10 6 kwh/y

36 Costs of Does it pay off??? Investiments (Equipments & Construction) Energy (Demand & Consumption) Feasibility Plant flow, local aspects

37 Energy recovery at conventional WWTP Electrical energy Thermal energy Heat exchangers Fuel for thermal sludge driers San Fernando WWTP Medellin, Colombia

38 San Fernando WWTP Medellin, Colombia

39 San Fernando WWTP, energy recovery Energy from biogás 2,081 kwh/h Energy for other equipments 510 kwh/h Lost 414 kwh/h Eléctrical energy generated 710 kwh/h Thermal energy generated 661 kwh/h Equipment Operatión 200 kwh/h Used 247 kwh/h

40 Along the 7 first years of operation the San Fernando WWTP produced 25,000,000 m 3 biogás (65% CH 4 y 33% CO 2 ), or 52,000 ton CO 2 e/year

41 Bello WWTP, Medellin, Colombia Digestors Gas holders Energy motors

42 Huge experience in Chile VENICE, 2010 La Farfana, 9 m 3 /s Santiago, Chile MM 3 /year Energy for the plant Heat for digestors Gas to the city Metrogas Company

43 Metrogas La Farfana project (US$ 5 million)

44 Energy recovery: from UASB reactors and from convencional WWTP digestors Arrudas WWTP, Belo Horizonte, Brasil Activated Sludge with energy recovery from the digestors biogas.

45 Arrudas WWTP Belo Horizonte, Brasil

46 Energy recovery at Arrudas WWTP Biogas Flare Gas holders Electric Energy Biogas Treatment µturbinas Digestors µturbinas µturbinas Sludge recirculation Gases Heat exchanger

47 Energy recovery at Arrudas WWTP Gas purification Microturbines

48 Barueri WWTP São Paulo, Brasil

49 Alegria WWTP Rio de Janeiro

50 Think big: can we make sanitation sustainable? An evaluation of sanitation, health implications, costs, development, economy. Economical x new technologies Biofilm control technology? Nanotechnology? New membranes? Sludge and Biogas recovery?

51 MAKING SANITATION SUSTAINABLE CAN WE MAKE IT?

52 THANK YOU Eduardo Pacheco Jordão, Dr.Eng.