POWER GENERATION FROM

Transcription

1 POWER GENERATION FROM MUNICIPAL SOLID WASTE Chicken Litter & Sewage Sludge GREATER GABORONE, Botswana November 2010 Botsile Gubago G4 Consulting Engineers

2 Waste Disposal in Greater Gaborone Greater Gaborone comprises; City of Gaborone : Pop. 200,000 Mogoditshane : Pop. 60,000 Tlokweng : Pop. 40,000 Waste Generation Rate Municipal Solid Waste : 65,000tons/yr Chicken Litter : 64,000tons/yr Sewage Sludge : 2,500ton/yr

3 Municipal Solid Waste (MSW) Problem compounded by rapid growth in population In Gaborone land for land filling very limited Regional landfill opened 35 km outside City This has resulted in increased haulage cost, as well as associated carbon footprint. Open dumping in vacant spaces common

4 Chicken Litter Chicken consumption has increased in Botswana, and so has chicken production. A major chicken producer has 14 chicken production farms within 30km of Gaborone, each with an average stock holding of 40,000 chicks per cycle. Total chicken litter production for this one producer is currently 60,000tons/year. Litter is disposed of semi dry at landfills, while a small portion is taken by farmers as manure. Chicken producers are keen to have the litter disposed of properly but do not have the means.

5 Sewage Sludge Rapid population growth and land requirements have resulted in departure from sewage ponds to modern wastewater treatment plant. The activated sludge sewage treatment plant has 40,000m³/day capacity & serves City of Gaborone, Mogoditshane, Kgale and Tlokweng. Expected sludge production is 16tons/day in 2015 and 20tons/day over the 15 year life span of proposed project. Another by-product of the sewage treatment plant is sludge gas and 5,000,000 m³/year of it is available for power generation

6 Botswana Strategy for Waste Management (Adopted 1998) 1.Waste Reduction Can quantity of waste produced be minimised? 2. Reuse/ Recycling Can waste be reused/recycled? 3. Treatment Does hazardous nature of waste need to be reduced? 4. Safe Landfill Disposal Waste Management Hierarchy 5. Incineration for Power Generation

7 Power Generation from Waste Waste disposal problem presents opportunity Aim to address waste disposal in sustainable manner Incentives for the project are as follows; Revenue from electricity sales Revenue from tipping fees Carbon Credits Project Benefits Environmental protection Employment creation Reduction on Botswana s carbon footprint

8 Credit Period Year MSW POWER GENERATION POTENTIAL Population Growth Waste after recycling CH 4 Production (CH 4 Avoided) CERs (CH 4 ) Tons of CH 4 CERs kwh - MSW MSW Combustion Plant Size MW to Grid CO 2 eq Avoidance (tons/yr) (m 3 /yr) (tons/yr) (tons/ yr) (kwh/yr) (MW) (MW) (tons/yr) ,903 59,532 1,071, ,650 35,897, , ,746 60,300 1,085, ,839 36,360, , ,638 61,078 1,099, ,030 36,830, , ,581 61,866 1,113, ,224 37,305, , ,574 62,664 1,127, ,420 37,786, , ,620 63,472 1,142, ,619 38,273, , ,844 64,316 1,157, ,827 38,782, , ,124 65,172 1,173, ,037 39,298, , ,462 66,039 1,188, ,251 39,821, , ,857 66,917 1,204, ,467 40,350, , ,311 67,807 1,220, ,686 40,887, , ,688 68,682 1,236, ,901 41,415, , ,121 69,568 1,252, ,119 41,949, , ,612 70,465 1,268, ,340 42,490, , ,161 71,374 1,284, ,564 43,038, ,431

9 Chicken Litter Power Generation Credit Period Year Litter Production kwh from Combustion Annual CH 4 Emission CH 4 Avoidance Plant Size Power to Grid Tons CO 2 e Avoidance (tons/yr) 90% cf) (tons/yr) CERS/yr (MW) (MW) tons/yr ,908 81,066,941 4,284 89, , ,758 82,112,705 4,339 91, , ,619 83,171,959 4,395 92, , ,492 84,244,877 4,452 93, , ,375 85,331,636 4,509 94, , ,270 86,432,414 4,568 95, , ,205 87,581,965 4,628 97, , ,152 88,746,805 4,690 98, , ,111 89,927,138 4,752 99, , ,084 91,123,168 4, , , ,069 92,335,107 4, , , ,038 93,526,229 4, , , ,018 94,732,718 5, , , ,012 95,954,770 5, , , ,018 97,192,586 5, , ,754

10 Sewage Sludge Power Generation Credit Period Year Estimated Cake Prod. Sewage Sludge Cake Sewage Gas Total Benefits kwh/year Generation Plant Size CO 2 Displacem ent Excess Sewage Gas Gas Plant Size CO 2 Plant Capacity Displacement Power to Grid CO 2 Displacement (tons/yr) kwh/year (MW) (tons/yr) (m³/yr) (MW) (tons/year) (MW) (MW) (tons/yr) ,212 3,436, ,749 1,162, , , ,504 3,749, ,999 1,219, , , ,833 4,101, ,281 1,575, , , ,840 6,248, ,999 1,929, , , ,915 6,329, ,064 2,283, , , ,992 6,411, ,129 2,637, , , ,071 6,496, ,197 2,991, , , ,152 6,582, ,266 3,345, , , ,234 6,670, ,336 3,699, , , ,317 6,758, ,407 4,053, , , ,401 6,848, ,479 4,407, , , ,486 6,939, ,552 4,761, , , ,570 7,029, ,624 5,115, , , ,654 7,120, ,696 5,469, , , ,740 7,212, ,770 5,822, , ,801

11 Combined Power Generation Credit Period Year Sewage Gas Gas Plant Size MSW Wastes Generated Sewage Sludge Chicken Litter Total Power Generation Plant Size Power to Grid (90%) (m³/yr) (MW) (tons/yr) (tons/yr) (tons/yr) (tons/yr) (MW) (MW) ,162, ,376 3,212 65, , ,219, ,400 3,504 66, , ,575, ,437 3,833 67, , ,929, ,488 5,840 68, , ,283, ,552 5,915 69, , ,637, ,630 5,992 70, , ,991, ,755 6,071 71, , ,345, ,896 6,152 72, , ,699, ,052 6,234 73, , ,053, ,223 6,317 74, , ,407, ,409 6,401 75, , ,761, ,576 6,486 76, , ,115, ,757 6,570 77, , ,469, ,953 6,654 78, , ,822, ,165 6,740 79, ,

12 Waste-to-Energy Technology Options Landfill with Gas Recovery Oldest and widely used with lower initial capital costs But due to high land requirement not suitable for Gaborone Anaerobic Digestion/Gasification/Pyrolysis Requires waste segregation to produce useful gases Landfilling required for what s unsuitable hence not suitable Mass Burn/Incineration Can burn almost anything and requires little sorting Maximum volume reduction for final waste disposal Suitable for co-firing with other Waste forms

13 Plant Configuration Proposal Phase I Phase II Total Plant Capacity 1800tpd Additional 500tpd BOILER No tpd 24 MW Nominal BOILER No tpd 24 MW Nominal BOILER No.3 500tpd 15MW Nominal

14 Plant Configuration Proposal Phase I Phase II Total Plant Capacity 140,000tons/yr Additional 50,000tons/yr BOILER No.1 20 MW Nominal BOILER No MW Nominal

15 PROJECT COSTS & BENEFITS (Phase I) Unit Price for Electricity U$/kWh (0.281Pula/kWhr) Unit Price for Carbon Credit 11.00U$/CER 1 Plant Capacity MW Net Power to Grid MW Capital Costs US$(M) Operating Costs/yr US$(M) Revenue/yr 5.1 Electricity US$(M) Methane Avoidance US$(M) Carbon Dioxide Avoidance US$(M) Tipping Fee (MSW) US$(M) Total Revenue US$(M) Gross Profit US$(M) 6.5

16 Project Schedule Pre Feasibility Study Completed October 2009 Submit Application for Reclamation Rights September 2010 Commence Plant Design & EIA 1 st Quarter 2011 Complete Bankable Feasibility Study 3 rd Quarter 2011 Funding Negotiations 4 th Quarter 2011 Commence Construction 1 st Quarter 2012 Plant Operation 3 rd Quarter 2013

17 Government Support Ministry of Local Government Ministry of Environment

18 THANK YOU