The Effects of Organic Waste Diversion on Landfill Gas Generation from U.S. Landfills Maryland Recycling Network 2016 Conference June 21, 2016 Alex Stege, SCS Engineers
Introduction Organic waste diversion Changes in organic MSW disposal Lower landfill gas generation Lower GHG (methane) emissions Reduced methane fuel supply for landfill gas to energy projects 2
Purpose of Study Document historic changes in organic MSW disposal Develop & model alternative future organic MSW disposal scenarios Evaluate effects of organics diversion on landfill gas generation 3
GHG Emissions from Waste Disposal Methane emissions from landfills = largest GHG source in waste sector Large GHG emissions reduction from: Diverting organic waste from disposal Collecting landfill gas and generating electricity 4
Types of Models (1) Lifecycle Analysis e.g. WARM Accounts for all emissions by material Full life-cycle benefits from diversion Time independent e.g. 100 years Good for long-range planning Not good for monitoring progress from baseline for specific sources (landfills) 5
Types of Models (2) Emissions Inventory e.g. LandGEM Emissions from a specific source over time No accounting outside of source 6
Estimating Landfill Methane Emissions Emissions and emissions avoidance estimates not precise Variations in landfill methane emissions Methane generation Methane recovery Methane oxidation 7
Landfill Gas Generation Models LandGEM LandGEM well known Adjusting key assumptions for site conditions poorly known Regulatory vs. non-regulatory models IPCC Offers calculations by material category Option for GHG emissions reporting Similar climate adjustment limitations as LandGEM 8
MSW Disposal/Diversion Data U.S. EPA (2015 for 1990-2013) Composition of U.S. MSW generated, diverted, and disposed EREF (2015) 2013 U.S. MSW disposal was 50% higher than reported by EPA 9
2000-2013 U.S. Organic MSW Disposal (EPA data adjusted to EREF totals) Thousand Tons MSW Disposed 80,000 70,000 60,000 50,000 40,000 30,000 20,000 10,000 0 2000 2005 2007 2009 2011 2012 2013 Paper Food Waste Yard Waste Wood Textiles Rubber, Leather, Diapers 10
% of Amount Generated 2000-2013 U.S. Organic MSW Diversion %s (EPA data) 70% 60% 50% 40% 30% 20% 10% 0% 63% 60% 40% 16% 14% 5% 2000 2005 2007 2009 2011 2012 2013 Paper Food Waste Yard Waste Wood All other organics Total Organics 11
Declines in U.S. Organic Waste Disposal Year Million Mg MSW Disposed % Organics in MSW Million Mg Organic MSW Disposed 1990 240 74.9% 180 2000 239 70.5% 168 2005 239 67.7% 162 2007 236 66.3% 156 2009 222 65.5% 145 2011 224 64.8% 145 2013 229 64.9% 149 12
Declining Methane Productivity of U.S. Waste Year Million Mg MSW Disposed Average MSW L 0 (m 3 /Mg) L 0 x Mg MSW Disposed (% decline since 1990) 1990 240 102.7 -- 2000 239 97.2 5.9% 2005 239 91.0 11.9% 2007 236 87.7 16.3% 2009 222 81.3 26.8% 2011 224 79.5 27.7% 2013 229 79.7 25.8% 13
Effects of 1990-2013 Declines in U.S. MSW Organics 17% decrease in organic MSW disposed 26% decrease in methane productivity of MSW disposed Does not = 26% decline in LFG generation Delayed effect depends on decay rates and timing of disposal 14
Future MSW Disposal Scenarios Define for organic MSW categories Disposal = Generation x (1-% Diversion) Generation defined by 2009-13 trends Discounted future MSW generation in medium and high diversion scenarios Diversion scenarios 1. Baseline continue 2009-13 trends 2. Mid-range 2 x Baseline diversion % increases 3. High 4 x Baseline diversion % increases 15
% of Amount Generated Baseline U.S. Organic MSW Diversion Forecasts 80% 70% 60% 50% 40% 30% 20% 10% 0% 68% 62% 42% 24% 17% 15% 2% 2009 2013 2016 2023 2030 Paper Food Waste Yard Waste Wood All other organics Total Organics 16
Thousand Tons MSW Disposed 60,000 50,000 40,000 30,000 20,000 10,000 0 Baseline U.S. Organic MSW Disposal Forecasts 2009 2013 2016 2023 2030 Paper Food Waste Yard Waste Wood Textiles Rubber, Leather, Diapers 12% increase in organic MSW disposal: 2013-2030 17
% of Amount Generated U.S. Organic MSW Diversion: Mid-Range Scenario 80% 70% 60% 50% 40% 30% 20% 10% 0% 2009 2013 2016 2023 2030 Paper Food Waste Yard Waste Wood All other organics Total Organics 18
Thousand Tons Disposed U.S. Organic MSW Disposal: Mid-Range Diversion Scenario 60,000 50,000 40,000 30,000 20,000 10,000 0 2009 2013 2016 2023 2030 Paper Food Waste Yard Waste Wood Textiles Rubber, Leather, Diapers 2% decrease in organic MSW disposal: 2013-2030 19
% of Amount Generated U.S. Organic MSW Diversion: High Scenario 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% 2009 2013 2016 2023 2030 Paper Food Waste Yard Waste Wood All other organics Total Organics *Meets US EPA food waste diversion goal of 50% by 2030 20
Thousand Tons Disposed U.S. Organic MSW Disposal: High Diversion Scenario 60,000 50,000 40,000 30,000 20,000 10,000 0 2009 2013 2016 2023 2030 Paper Food Waste Yard Waste Wood Textiles Rubber, Leather, Diapers 30% decrease in organic MSW disposal: 2013-2030 21
LFG Flow at 50% Methane (scfm) LFG from U.S. MSW Disposed 2000-2030 2,000,000 1,750,000 1,500,000 1,250,000 1,000,000 750,000 2010 2015 2020 2025 2030 Baseline LFG Generation Medium Diversion LFG Generation High Diversion LFG Generation 22
% Decrease from Baseline U.S. % Decreases from Baseline Mid-Range Diversion 15.0% 12.5% 10.0% 7.5% 5.0% Organic Tons Organic WIP LFG Generation 2.5% 0.0% 2020 2025 2030 23
U.S. % Decreases from Baseline High Diversion 40% 35% % Decrease from Baseline 30% 25% 20% 15% 10% 5% Organic Tons Organic WIP LFG Generation 0% 2020 2025 2030 24
CA Organic MSW Disposal: Baseline Tons Disposed 9,000,000 8,000,000 7,000,000 6,000,000 5,000,000 4,000,000 3,000,000 2,000,000 1,000,000 0 2003 2008 2014 2016 2023 2030 Paper Food Waste Yard Waste Textiles Wood, rubber, leather Composite organic 12% decrease in organic MSW disposal: 2014-2030 25
Tons Disposed CA Organic MSW Disposal: Mid-Range Diversion Scenario 7,000,000 6,000,000 5,000,000 4,000,000 3,000,000 2,000,000 1,000,000 0 2008 2014 2016 2023 2030 Paper Food Waste Yard Waste Textiles Wood, rubber, leather Composite organic 43% decrease in organic MSW disposal: 2014-2030 26
Tons Disposed CA Organic MSW Disposal: High Diversion Scenario 7,000,000 6,000,000 5,000,000 4,000,000 3,000,000 2,000,000 1,000,000 0 2008 2014 2016 2023 2030 Paper Food Waste Yard Waste Textiles Wood, rubber, leather Composite organic 71% decrease in organic MSW disposal: 2014-2030 27
LFG Flow at 50% Methane (scfm) LFG from CA MSW Disposed 2000-2030 160,000 140,000 120,000 100,000 80,000 60,000 40,000 20,000 0 2010 2015 2020 2025 2030 Baseline LFG Generation Medium Diversion LFG Generation High Diversion LFG Generation 28
CA % Decreases from Baseline Mid-Range Diversion 40% 35% % Decrease from Baseline 30% 25% 20% 15% 10% 5% Organic Tons Organic WIP LFG Generation 0% 2020 2025 2030 29
% Decrease from Baseline CA % Decreases from Baseline High Diversion 70% 60% 50% 40% 30% 20% Organic Tons Organic WIP LFG Generation 10% 0% 2020 2025 2030 30
% Decrease from Baseline CA High Diversion: Dry vs. Wet Climate 35% 30% 25% 20% 15% 10% Dry Climate Wet Climate 5% 0% 2020 2025 2030 31
Summary From 2009-2013, organics diversion increased by 1% and generation increased by 3%, causing a 2% disposal increase Continuing disposal trends LFG increases Aggressive increases in recycling would be required to cause LFG generation declines 32
For More Information Alex Stege, Senior Project Advisor SCS Engineers, Phoenix, AZ astege@scsengineers.com 33