WHY WASTE TO ENERGY (WTE)?

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1 WASTE TO ENERGY TECHNOLOGIES Missouri Waste Control Coalition Laura Drescher Monday, July 13 th, 2015 WHY WASTE TO ENERGY (WTE)? Heightened interest in green energy with President Obama calling for 80% of energy from renewable sources by 2035 during the 2011 State of the Union address. Federal government and some states count MSW as a renewable source. Potential financial incentives for projects: Carbon emission reduction credits Renewable energy credits Tax credits Developers approaching City Councils about technologies: May count towards waste reduction and recycling May be cost competitive with transfer/disposal in some places 2 1

2 3 WTE BY THE NUMBERS In 2012, the US generated approximately 251 million tons of MSW, only 34.5% of which was recycled of composted. 1 MSW generation increasing an average of 9% per year since In 2012, the EPA reported that 12% of MSW being used to produce energy. 1 Combusting all of the MSW currently landfilled can reduce emissions by 70 to 120 million metric tons of CO 2 equivalent per year. 2 Combustion of MSW emits less CO 2 per mega watt hour of electricity generation than do fossil fuels. 3 Over half of the states that have a renewable energy goal classify MSW as a renewable fuel and 15 states have categorized MSW as a renewable resource in their renewable portfolio standards. 1. USEPA (2014a). Municipal Solid Waste GeneraBon, Recycling, and Disposal in the United States. Tables and Figures for Retrieved from hop:// 2. USEPA (2009). OpportuniBes to Reduce Greenhouse Gas Emissions through Materials and Land Management PracBces. Available online at: hop:// 3. USEPA (2014b). Energy Recovery from Waste. Retrieved May 12, 2014 from: hop:// 4 2

3 WHICH WTE TECHNOLOGY IS RIGHT FOR ME? 1. EXPLORE THE TECHNOLOGIES. 2. ASK THRESHOLD QUESTIONS. 3. IDENTIFY AND APPLY THE ASSESSMENT CRITERIA. 4. DEVELOP COMPARATIVE MATRIX AND RANK TECHNOLOGIES. 5. SEEK ASSISTANCE. 5 EXPLORE THE TECHNOLOGIES 6 3

4 PREPROCESSING Shredding or decreasing feedstock in size Separate recyclables from MSW & dispose of unrecyclable material Removes materials that are problematic for selected technology Mechanical and manual sorting 7 SUMMARY OF WTE TECHNOLOGIES FOR MSW Biological Thermal Anaerobic DigesBon GasificaBon (Plasma Arc) Bioreactor Landfill IncineraBon FermentaBon Pyrolysis 8 4

5 GASIFICATION Thermo- chemical decomposibon of maoer at temperatures in excess of 700 o C, occurring in an environment with limited or no oxygen in order to promote conversion of organic material to methane (CH 4 ), carbon monoxide (CO) and hydrogen (H 2 ). 9 PLASMA ARC GASIFICATION Extremely high heat (>3,000 degrees C) produces super heated gas and inorganic solid by-products. Typically combined with gasification or pyrolysis for conversion of hot gases to syngas. Used in steel refining for decades One commerical scale and two pilot facilities operating with MSW in Japan. Operating (120,000 tpy) and planned (160,000 tpy) facility in Ottawa, Ontario. Hurlburt Field AFB has 10 TPD facility processing MSW No full-scale facilities operating with MSW in US Hurlburt Field Air Force Base 10 TPD MSW 10 5

6 INCINERATION Thermal decomposibon with excess oxygen resulbng in heat and ash. Mass burn Advanced Thermal Recycling RDF systems combusbon 11 PYROLYSIS Process through which feedstock is heated and broken down without the addibon of oxygen, and converted into carbon, oil, or gas. 12 6

7 ANAEROBIC DIGESTION The biological conversion of organic maoer to methane (CH 4 ) and carbon dioxide (CO 2 ) in an oxygen free, water- based environment. Proven method of managing organic materials in the US: Wastewater treatment sludge Agricultural waste Small units at food processors, large groceries or markets, etc. 13 BIOREACTOR LANDFILL A burial waste disposal site in which waste degradabon is accelerated through the addibon of liquids, such as leachate or other liquids, and oxygen to enhance microbial processes and methane producbon. 14 7

8 FERMENTATION Feedstock transformabon process that includes a hydrolysis stage, acetogenic stage (bacteria decompose the products from hydrolysis into an acebc acid, hydrogen, carbon, and other products), and methanogenic stage (lignocellulosic materials are split into proteins, faoy acids, and sugars through an enzymabc process). 15 SECONDARY TECHNOLOGIES Torrefaction Thermal preprocessing step Microwave - An emerging pyrolysis performed under oxygen-free conditions to method that applies high energy radiation improve the chemical and physical to generate heat within the material being composition of biomass to form bio-coal processed. for energy production. Transesterification - Process through Depolymerization - The breakdown of which diesel-type fuel is produced from an long-chain polymer molecules to shorter oil that contains triglycerides and free fatty molecules under conditions of low heat and acids. low pressure. For example, in the waste to energy context, scrap plastic is turned into monomers with the properties and performance of virgin resins to rebuild plastics. Pressure/steam processes - Waste treatment approach involving the use of an autoclave as the primary energy recovery process. Liquefaction - The conversion of a solid waste to liquid form. Algal processes - Photosynthetic organisms and a source of renewable biofuel (lipids produced by the algae are harvested to produce a hydrocarbon-based fuel). 16 8

9 HEAT RECOVERY Direct conversion of excess process heat to energy. Two primary uses: Thermal for heating or refrigeration Electricity generation Feasibility of heat recovery depends on: Heat quantity Composition Operating schedules Availability Facility demand requirements Combined Heat & Power (CHP) achieve efficiencies of 60-80% for producing electricity and thermal energy USEPA (2014d). Efficiency Benefits. Retrieved June 13, 2014 from: USEPA (2014f). Green Power Market: Green Power Defined. Retrieved June 13, 2014 from: hop:// gpmarket/ 17 ASK THRESHOLD QUESTIONS 18 9

10 THRESHOLD QUESTIONS 1. Has the technology been used to manage the targeted waste streams? For example, plasma arc gasification has been used to manage various types of hazardous and industrial wastes, but historically has not been commercially applied to convert mixed municipal solid waste. 2. Is there a reference facility using the technology that is operating commercially or as a demonstration facility? The distinction between a commercially operating and a demonstration facility is that the commercially operating facility has operated on a continuous basis; the demonstration facility usually has not. 19 IDENTIFY AND APPLY THE ASSESSMENT CRITERIA 20 10

11 ASSESSMENT CRITERIA Types of net energy produced. Commercial readiness. Quantities and mix of feedstock. Byproducts/residuals. Flexibility. Compatibility with existing system. Capital and operations costs. Environmental and regulatory issues. 21 TYPES AND NET ENERGY PRODUCED Alcohol Biodiesel Methane Steam Electricity Some further transformation may be required to obtain marketable energy products. Energy per ton of feedstock represents a viable measure of energy yield

12 QUANTITIES AND MIX OF FEEDSTOCK MSW C&D Source separated organics Sludges Additional preprocessing may be required 23 BYPRODUCTS/RESIDUALS Non-energy materials. Ash Water Wastewater May require treatment or disposal Potential for beneficial reuse (especially bottom ash or char) Estimated as a percentage of the total inputs 24 12

13 CAPITAL AND OPERATING COST Define project parameters Project throughput Technology Type of energy produced General site parameters Planning-level capital costs Design & Permitting Construction Equipment Operations and Maintenance Costs 25 ENVIRONMENTAL & REGULATORY ISSUES Vary with project-specific parameters and local and regional regulatory agencies Permit applications and reviews of facility construction and operating permits Characterize fatal flaw regulatory issues (pollution control for air emissions, disposal of contaminants) Potential for reductions in greenhouse gas emissions Reductions should be characterized by high, medium, low, or no change. Greenhouse gas emission generation activities include collection, transportation, processing, and disposal. Other environmental impacts include contamination issues and stormwater management

14 COMMERCIAL READINESS Refers to the technical maturity of the technology. Pilot phase or R&D phase May have success with one type of feedstock but may have limited application to another Regionally dependent 27 FLEXIBILITY How can technology adapt to changing internal and external project factors:. Regulatory Project throughput Feedstock quality Feedstock mix Technology must be maintained and updated with advances in technology. Rated as low, medium, or high 28 14

15 COMPATABILITY WITH EXISTING SYSTEM Compatibility with existing solid waste management system in the community 29 DEVELOP COMPARTIVE MATRIX AND RANK THE TECHNOLOGIES 30 15

16 COMPARATIVE MATRIX 31 GASIFICATION Types of net energy produced BTU/scf of syngas Quantities and mix of feedstock MSW with preprocessing, homogenous material such as plastics is preferable Byproducts/residuals liquid byproducts, including tars, oils, and other compounds, and solid fractions Capital and operations costs Capital Cost: $230,000 to $425,000 per daily ton of capacity Operations Cost: $40 to $70 per ton of feedstock processed Environmental and regulatory issues Particulate and gaseous emissions Permitting, lack of regulatory limits Commercial readiness Commonly utilized for other feedstocks, but still emerging for processing of MSW Flexibility Medium: varied feedstock characteristics, temperatures, pressures, time, oxygen, moisture 32 16

17 INCINERATION Types of net energy produced Steam (for heating) & Electricity (for sale), KWh/ton Quantities and mix of feedstock MSW; mixing residential with industrial, commercial, and institutional waste is preferable; water Byproducts/residuals 20-30% bottom ash, 2-5% metals, 2-6% APC residues Capital and operations costs Capital Cost: $260,000-$380,000 per daily ton design capacity Operations Cost: $30-$50 per ton processed Environmental and regulatory issues Air emissions Air, solid waste, and stormwater permitting; emissions guidelines Commercial readiness Many successful facilities in US, far more in Europe and Japan; growth over the last years Flexibility High: flexibility with feedstock, systems easy to modify and expand, though public perception ca be negative 33 PYROLYSIS Types of net energy produced Bio-oil (60-80 gal. per ton MSW) and gas Quantities and mix of feedstock MSW with preprocessing, homogenous material such as plastics is preferable Byproducts/residuals Biochar (charcoal utilized for beneficial reuse) and ash Capital and operations costs Capital Cost: $250,000 to $500,00 per daily ton MSW capacity Operations Cost: $30-75 per ton MSW processed Environmental and regulatory issues Disposal of ash and air emissions Stormwater permitting, inclusion as a renewable resource, permitting of byproducts for beneficial reuse Commercial readiness Commercially operating using MSW in Europe and Asia, but demonstration facilities in U.S. Flexibility Limited: requires pre-processing of MSW for application. Recent interest in bio-oil

18 ANEROBIC DIGESTION Types of net energy produced BTU/scf biogas (50%- 70% methane and 30-45% carbon dioxide) Quantities and mix of feedstock Sewage sludge; farm waste; food production waste; source separated organics from MSW Byproducts/residuals Digestate and liquids. Both can be reused or post-processed Capital and operations costs Capital Cost: $251-$315 per ton installed capacity Operations Cost: $40-$140 per ton processed Environmental and regulatory issues. Air emissions associated with digestate processing, leachate management, noise, odor, litter nuisances, dust Commercial readiness Commonly utilized with other organic matter (including biosolids) for many years; limited number of US facilities processing organic materials from MSW Flexibility Medium: flexibility in feedstock and use of byproducts 35 LANDFILL BIOREACTOR Types of net energy produced Up to 100m 3 of methane per ton of waste, with effective energy yield of 60 m 3 per ton of waste (if converted to electricity, 193 kwh/ton) Quantities and mix of feedstock Mixed MSW Byproducts/residuals Non-degraded MSW Capital and operations costs Capital Cost: Comparable to conventional landfill development costs Operations Cost: Comparable to costs for a conventional landfill with energy recovery Environmental and regulatory issues Fugitive methane emissions, carbon storage Permitting and siting Commercial readiness Well-established Flexibility High: can accept a broad range of waste streams 36 18

19 FERMENTATION Types of net energy produced Ethanol production of 50 to 70 gallons per dry ton organic feedstock Quantities and mix of feedstock Cellulosic Biomass (e.g., organic fraction of MSW) Byproducts/residuals Stillage and carbon dioxide Capital and operations costs Capital Cost: Inadequate cost data available Operations Cost: Inadequate cost data available Environmental and regulatory issues Odor and air emissions Permitting, siting, and odor issues Commercial readiness Technology is mature, but no commercial facilities in the US using MSW as feedstock Flexibility Limited: requires feedstock with very limited contamination 37 SEEK ASSISTANCE 38 19

20 LESSONS LEARNED It always takes longer than anticipated. Most projects in the US that were expected to be operational, or at least under construction by now, are not. Some projects scaled down to reduce financing needs. Securing capital has been one of the key challenges. Exacerbated by recent economic conditions. Federal funds less available (American Recovery and Reinvestment Act funds allocated) 39 CONTACT INFORMATION Laura Drescher (816) Bob Craggs (952)

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