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Chapter 6 LCA and Waste Management. Example of Plastic Shopping Bags. Environmental impacts Leachate Methane Current methods of handling waste Recycling Bury Burn Compost Anaerobic digestion. Size of Problem. Increasing material acquisition, i.e. more kg/person thrown away
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Example of Plastic Shopping Bags • Environmental impacts • Leachate • Methane • Current methods of handling waste • Recycling • Bury • Burn • Compost • Anaerobic digestion
Size of Problem • Increasing material acquisition, i.e. more kg/person thrown away • Australia is 4.35 kg/day/person • Most households pay a set fee • Industry pays per kg • Incentive for reducing waste, more recycling in commercial facilities
Australia Data • Book lists Australia specific data • “Hard Part” • Definitions – What is MSW?? • Data quality/source • Go to pdf
6.2 Case Studies in LCA • Study in 1998 looked landfilling and recycling of glass, PET, and steel, studies were expanded • Modeling of recycling included • Reduced negative impacts of landfills • Virgin material avoided due to recycling • Also looked at positive benefit of landfill gas generation
Large Study of Recycling • Functional unit was the recyclable portions of paper and board, LPB, HDPE, PVC, glass, steel, aluminum • Fig 6.5 shows impacts of PET – benefits were greater when recycling • Environmental indicators • GHGE • Smog precursors • Embodied energy • Water use • Solid waste
Impacts Omitted • Human and eco-toxicity • There are some models (www.epa.gov/compliance/resources/cases/civil/caa/tvacoal-fired.html) • Land use and soil impacts in forestry and wheat production (?) • Local amenity of landfill (give some examples) • Resource consumption/depletion • Human behavior
Benefits of Landfilling • Some of organic fraction breaks down to methane and CO2 • Some methane is lost (very bad) • Remainder used for power generation
6.2 Environmental Economics and Recycling • Curbside recycling including financials, environmental, and social costs and benefits • Looked at numerous locations • Various recycling options • Paper and plastic with and without energy recovery • Packaging shift from PET to glass • All combustion • Microbial degradation
6.2.4 Plastic Shopping Bags • Bags made from HDPE versus corn based maize • Functional unit – 70 pieces carried from grocery each week for 52 weeks • Looked at numerous waste management techniques • Landfill • Source separated green and food for composting • MSW composting • MSW anaerobic digestion
Summary • Landfills are the worst for resource depletion, water toxicity, GHGE • Importance of having well defined scope and goal • Assumptions could change results • Degradation rates • Recovery rates