Presentation at Eilat Eilot International Renewable Energy Conference & Exhibition, February 2010

Transcription

1 Presentation at Eilat Eilot International Renewable Energy Conference & Exhibition, February 2010 Converting a Major Environmental Problem to a Source to Renewable Energy By Jack Lauber and Nickolas J. Themelis, Earth Engineering Center, Columbia University

2 To approach sustainable development humanity must control emissions to water, air, and land The U.S. is doing a fairly good job with regard to water and air (except for greenhouse gases!) But.

3 When it comes to controlling emissions to land, we are behind, Denmark, France, Germany, Japan, the Netherlands, Singapore, Sweden, and Switzerland. Past abuses of the land at Superfund sites are well known and efforts are being made to address them. What is less understood is that the annual landfilling of 260 million tons of municipal solid wastes (MSW) converts about 25 square kilometers of greenfields to landfills, every year.

4 Hierarchy of Waste Management Recycling/composting is the first priority for managing solid wastes but. in many cases, recycling is practically impossible or more costly than use of virgin materials (e.g., 80% of U.S. plastics are still landfilled). Therefore, in advanced nations, the next priority, after recycling, is the recovery of energy and metals by controlled combustion (waste-to-energy or WTE).

5 WHAT IS NEEDED FOR SUCCESSFUL RECYCLING Communities that are willing to provide separate collection of recyclable materials (principally metals, paper/cardboard, green wastes). Citizens who are willing to spend some of their time in separating recyclables at the source (households). Markets that can use the recyclable materials at a profit to the recyclers (e.g. metal smelters; secondary paper mills). In absence of above conditions, government edicts that communities must recycle X% of their solid wastes end up in a waste of money and energy

6 Sustainable Waste Management: The Global Experience There are only two alternatives to manage postrecycling solid wastes: a) combustion with energy and metals recovery (Waste-to-Energy (WTE) or b) b) landfilling with landfill gas recovery (LFGTE) All countries and states that use these methods also have strong recycling efforts.

7 Alternative Daily Cover for LF

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9 Schematic diagram of the stoker ( Mass Burn ) WTE process- Dominant WTE technology with over 500 plants worldwide

10 The Air Pollution Control system of a modern WTE accounts for 50% of the capital and operating cost ( cleanest high temperature stack gas ) Maximum Achievable Control Technology (EPA s MACT): Dry scrubber, ammonia injection, activated carbon injection, fabric filter baghouse, continuous monitoring

11 THE GLOBAL WTE PICTURE (2002) Nation Million tonnes to WTE EU Japan 40.0 USA 26.3 Taiwan 7.0 Singapore 4.0 China 3.0 Switzerland and Norway 3.8 South Korea 1.0 All other 9 Total 143

12 Estimated Global Disposition of Post-Recycling Municipal Solid Wastes (in million tonnes) Combustion with energy recovery: <200 Landfills with some methane recovery: 200 Landfills without methane recovery: 800 Plus an undetermined amount disposed in dumps

13 The Global Landfilling Picture (N.J. Themelis and P. Ulloa, Methane generation in landfills, Renewable Energy 32 (2007) MSW to global landfills: 1 billion tons/y Landfill Gas (LFG) generation: 50 million tonnes CH 4 LFG collected and used or flared*: 6 million tonnes CH 4 LFG emitted globally: 44 million tonnes CH 4 * *Equivalent to 920 million tons of CO2 (over 3% of global Greenhouse Gases (GHG) *The US captures nearly 60% of this

14 State of the Garbage in America (Columbia University/BioCycle Survey of 2006 data (BioCycle, Dec. 2008) Recycling: 29% WTE: 8% Landfilling: 63%

15 Current renewable sources of electricity in the State of New York (EIA 2006) Source MWh % Combustion of biogenic fraction of MSW and from LFG recovery 1,410, % Wood and wood wastes 530, % Wind 655, % Solar 7, % Total RE*, excluding-hydro power 2,606, % * 2% of total electricity used in NYS

16 WTE is a major source of Renewable Energy in U.S. (DOE 2002) Energy source Billion kwh % of total renewable generated energy Geothermal % WTE (from 7.4% of % the MSW) Landfill gas (from % 64.1% of the MSW) Wood/other biomass % Solar thermal % Solar photovoltaic % Wind % Total % 1 short ton of MSW=550 kwh==1 barrel of oil

17 Advances in emission control of WTEs: Change in dioxin emissions from U.S. WTEs between 1987 (10,000 g TEQ) and 2002 (<10g TEQ) BBB WTE Total U.S. emissions: <10 grams TEQ

18 Total annual air emissions from landfilling 300,000 tons of solid wastes without LFG recovery: 5,120 tons methane 101 tons ammonia 1.9 tons sulfides/mercaptans 1.3 tons toluene 0.52 tons dichloromethane 0.29 tons tetrachloroethylene 0.29 tons vinyl acetate 0.24 tons acetone 0.17 tons xylenes 0.16 tons dichloroethane 0.16 tons trichloroethylene 0.13 tons vinyl chloride 0.09 tons styrenes Smaller amounts of another ten VOC compounds Source: Landfill gas composition as per Tchobanoglous et al Handbook x 62 Nm 3 of landfill gas/ton x 300,000 tons solid wastes

19 PROCESSING BOTTOM ASH FOR BENEFICIAL USE FOR BENEFICIAL USE OF BOTTOM ASH Remove ferrous and non-ferrous metals (700,000 tons/year in US) Crush/grind and screen to achieve particle distribution for particular construction use Integration with processing of conventional construction materials

20 Beneficial uses of WTE ash: Artificial Reefs (Prof.Frank Roethel, SUNY, Stonybrook) Four Artificial Reefs constructed in Long Island Sound between Structures Examined for Five Years Blocks maintained their structural Integrity

21 Beneficial uses of WTE ash: Artificial Reefs (Prof.Frank Roethel, SUNY, Stonybrook) Metals did not leach from the Ash Blocks Biological communities were diverse and identical to those found on control surfaces (rocks, etc.)

22 Beneficial uses of WTE ash: Shore protection (Prof.Frank Roethel, SUNY, Stonybrook) James River, Virginia Demonstration Project Concrete blocks possess the durability to withstand the impact of the ocean

23 If WTE is environmentally better than landfilling, why is the U.S. behind other developed nations? Other nations provide incentives for WTE and directives away from landfilling. In Japan and the E.U., there are laws that prevent the transport of solid wastes to other communities or states. Denmark with a population of 5 million has about 30 WTEs that are located at populated centers so that not only the electricity but also the waste heat of the WTES can be used for district heating. In Denmark, 18% of the district heating is provided by the combustion of MSW.

24 In the U.S., MSW can be transported over long distances to landfills anywhere economics allow, without consideration of the environmental costs For example, the transport of NYC MSW to Pennsylvania, Virginia and Ohio requires over ten million diesel truck miles and results in PM emissions that are several times higher than would be emitted if the MSW were combusted in WTE plants near NYC

25 Interstate Transport of Municipal Solid Wastes (Congressional Research Service, 2006)

26 Covanta Energy - Babylon (NY)

27 Covanta Energy-Bristol (CT)

28 Covanta Energy - Lee County(FL)

29 A very new WTE facility: On the River Seine, 4 kilometers from Eiffel Tower Examples - Paris Issy Bild 29

30 Winner of Columbia/WTERT 2006 Industry Award: ASM Brescia, Italy