Presentation on theme: "Urban waste management in a carbon constrained economy Bruce Edgerton Manager: Sustainability Policy."— Presentation transcript:
Urban waste management in a carbon constrained economy Bruce Edgerton Manager: Sustainability Policy
Key Messages Implications of a carbon constrained economy for urban waste management: 1.get organics out of landfill; 2.recycle-recover materials to highest-value use were possible; 3.generate energy from appropriately sorted residual material; 4.explore the next generation of energy-from-waste technologies to: o Generate renewable energy or transport fuels and/or sequester carbon. Draft Waste Strategy & consultancies (www.environment.act.gov.au)www.environment.act.gov.au – Provide a good starting point for discussion – Public consultation on web – Biochar trial & further analysis of options underway Final ACT waste strategy to be released this year
Context ACT 1996 No Waste by 2010 released – Resource recovery: 43% in 1996 75% in 2005 71% in 2010 Climate Change & Greenhouse Gas Reduction Act (October) 2010 Federal Carbon Pricing Mechanism Carbon Farming Initiative (CFI) – Legacy landfill emissions – Biochar – Soil carbon (via compost?)
Potential new waste services, infrastructure & markets PEF = process engineered fuel a.k.a RDF
Three pronged approach Programs 1.Commercial waste scheme 2.Organics recovery 3.Energy from waste – Staged implementation – appropriately sorted residuals – i.e. no mass burn incineration Outcomes Resource Recovery > 80% by 2015 >85% by 2020 >90% by 2025 No recoverable material sent to landfill ie approximately 5-10% deemed unrecoverable Carbon neutral waste sector by 2020 – Implies offsets
The Role of Energy from Waste Adding value to under-utilised or landfilled waste streams – Thermal Coal Substitute =$50-150/tonne Creating valuable products from organic wastes o renewable electricity o biochar and/or liquid fuels
Conclusion ACT Government takes its climate change responsibilities seriously The draft ACT waste strategy is framed in this context The final waste strategy is to be released this year Waste management could contribute to climate change mitigation via: – avoided emissions from landfill o 2.5% of total GHG emissions – Avoided emissions via recycling o As important as landfill GHG emissions – but o doesn’t impact on the ACT’s GHG inventory – generating renewable energy – sequestering carbon &/or generating renewable transport fuels
draft waste strategy consultation 8 Dec 2010 to 28 Feb 2011 Released – draft ACT Sustainable Waste Strategy 2010-2025 – URS- EcoWaste & Inovact consultancy reports Held – 6 community forums – 1 waste-industry forum – 3 presentations at waste conferences 2010-11 Results – All submissions made public (www.environment.act.gov.au/waste)www.environment.act.gov.au/waste – Generally quite positive feedback o Including for energy-from-waste... providing it was staged and/or “right sized” not incinerated – Want more services o E-waste recycling o Bulky waste collection o Garden waste collection “ Time to talk- Canberra 2030” 20,000 participants & 34,000 submissions Third bin was 45 out of 1000 issues – ACT has high service provision expectations... and Queanbeyan already has a garden-waste bin!
1.C&D largest material stream 2.Garden waste 3.Commercial waste 4.Household waste 5.Urban forest & biosolids underutilised
Energy-from-waste: technology options Landfill gas In-vessel anaerobic digestion Direct combustion Process Engineered Fuels (PEF) - for export outside the ACT Advance thermal options Gasification Slow pyrolysis Flash pyrolysis Plasma et al.
Appropriate feedstocks for EfW Dry – tonnes/yr of dry matter C&D timber – 15-30,000 Urban forest material – 10,000 and growing Dry commercial waste (PEF) – 10-25,000 Garden waste – 180-240,000 Wet - tpa dry (tpa wet) Biosolids (sewage sludge) – 13-15,000 (30-45,000) Sorted commercial organics – 8-16,000 (20-35,000) Sorted domestic organics – 10-20,000 (30-40,000) Green – available now (3-10MW) Orange – potentially available by 2015 Red – post 2015 or not available
Biochar Trial manufactured by AnthroTerra using low temperature (≈450 o C) pyrolysis Biochars 1.C&D timber – micro & macronutrients added after pyrolysis 2.C&D timber – torrefied with biosolids at 250 o C after pyrolysis 3.C&D timber + biosolids 4.household organics (from MSW) – from SITA’s Kemp’s Creek residual- waste MRF (SAWT) processing Liverpool’s residual waste bin 5.Urban forest material (green waste) + biosolids Results Sequestration – 33-54% kg biochar/kg dry input – 71-92% stable carbon Energy yield – C&D timber + dry green waste ≈ 19 MJ/dry tonne – Biosolids & household organics = 12.5 - 13.8 MJ/dry tonne Agronomic quality??? – Looks good – High Zn, Pb, Cu, Cr in MSW
Biochar Pot Trials ANU Fenner School of Environment & Society >1600 pots 0.5-6% biochar blended with – compost made from garden waste in the ACT – a local top soil 5 species – Breccia – Pansy – Acacia – Annual grass – Perennial grass