A life cycle comparison of disposal and beneficial use of coal combustion products in Florida
- 255 Downloads
Background, Goal, and Scope
Currently, only 40%, or 44.5 million metric tons, of coal combustion products (CCPs) generated in the United States each year by electric utilities are diverted from disposal in landfills or surface impoundments and recycled. Despite promising economic and environmental savings, there has been scant attention devoted to assessing life cycle impacts of CCP disposal and beneficial use. The objective of this paper is to present a life cycle inventory considering two cases of CCP management, including the stages of coal mining and preparation, coal combustion, CCP disposal, and CCP beneficial use. Six beneficial uses were considered: concrete production, structural fills, soil amendments, road construction, blasting grit and roofing granules, and wallboard.
Primary data for raw material inputs and emissions of all stages considered were obtained from surveys and site visits of coal-burning utilities in Florida conducted in 2002, and secondary data were obtained from various published sources and from databases available in SimaPro 5.1 (PRé Consultants, Amersfoort, The Netherlands).
Results revealed that 50 percent of all CCPs produced, or 108 kg per 1,000 kg of coal combusted, are diverted for application in a beneficial use; however, the relative amounts sold by each utility is dependent on the process operating parameters, air emission control devices, and resulting quality of CCP. Diversion of 50% of all CCPs to beneficial use applications yields a decrease in the total raw materials requirements (with the exception of gravel and iron) and most emissions to air, water, and land, as compared to 100% disposal.
The greatest reduction of raw materials was attributed to replacing Portland cement with fly ash, using bottom ash as an aggregate in concrete production and road construction in place of natural materials, and substituting FGD gypsum for natural gypsum in wallboard. The use of fly ash as cementitious material in concrete also promised significant reductions in emissions, particularly the carbon dioxide that would be generated from Portland cement production. Beneficial uses of fly ash and gypsum showed reductions of emissions to water (particularly total dissolved solids) and emissions of metals to land, although these reductions were small compared to simply diverting 50% of all CCPs from landfills or surface impoundments.
This life cycle inventory (LCI) provides the foundation for assessing the impacts of CCP disposal and beneficial use. Beneficial use of CCPs is shown here to yield reductions in raw material requirements and various emissions to all environmental compartments, with potential tangible savings to human health and the environment.
Recommendations and Perspectives
Extension of this life cycle inventory to include impact assessment and sensitivity analysis will enable a determination of whether the savings in emissions reported here actually result in significant improvements in environmental and human health impacts.
KeywordsCoal combustion beneficial use coal combustion products (CCPs) disposal emissions coal combustion Florida Life Cycle Inventory (LCI)
Unable to display preview. Download preview PDF.
- American Coal Ash Association (2003): 2001 Coal Combustion Product Production and Use. Alexandria, VAGoogle Scholar
- Halverson RR, Boggs B, Enyart J, Madden G (2001): Accelerated Nonpozzolanic Reactions of High Volume Coal Fly Ash Concrete. Proceedings of the 14th International Symposium on Management and Use of Coal Combustion Products. American Coal Ash Association, Alexandria, VAGoogle Scholar
- Stewart BR (1999): Coal Combustion Product (CCP) Production and Use. Biogeochemistry of Trace Elements in Coal and Coal Combustion Byproducts. Sajwan KS, Alva AK, Keefer RF (eds), Kluwer Academic/Plenum Publishers, New York, NYGoogle Scholar
- Gainer K (1996): Commercial Use of Coal Combustion Byproducts: Technologies and Markets, Report E-78. Business Communications Company, Inc., Norwalk, CTGoogle Scholar
- Dienhart GJ, Stewart BR, Tyson SS (eds) (1998): Coal Ash: Innovative Applications of Coal Combustion Products. American Coal Ash Association, Alexandria, VAGoogle Scholar
- Joshi RC, Lohtia RP (1997): Fly Ash in Concrete: Production Properties and Uses. Gordon and Breach Science Publishers, Amsterdam, The NetherlandsGoogle Scholar
- Mills RH (1990): The Practitioner’s View of Fly Ash Utilization. Fly Ash and Coal Conversion By-Products: Characterization, Utilization and Disposal VI. Day RL, Glasser FP (eds), Materials Research Society, Pittsburgh, PAGoogle Scholar
- Pratt PL (1990): The Use of Fly Ash in Concrete: A European View. Fly Ash and Coal Conversion By-Products: Characterization, Utilization and Disposal VI. Day RL, Glasser FP (eds), Materials Research Society, Pittsburgh, PAGoogle Scholar
- Ferguson G, Levorson SM (1999): Soil and Pavement Base Stabilization with Self-Cementing Coal Fly Ash. Alexandria, VA: American Coal Ash AssociationGoogle Scholar
- Butalia TS, Wolfe WE (2000): Market Opportunities for Utilization of Ohio Flue Gas Desulfurization and Other Coal Combustion Products. The Ohio State University; Dept of Civil and Environmental Engineering and Geodetic Science, Columbus, OHGoogle Scholar
- Taha R, Seals R, Tittlebaum M, Saylak D (1995): Environmental Characteristics of By-product Gypsum. Transportation Research Record 1486(10) 21–26Google Scholar
- National Gypsum Company (2003): 〈www.nationalgypsum.com/about/howmade.html〉 (accessed April 14, 2003)Google Scholar
- Bretz EA (1991): Innovation Key to Finding Unusual Ash Disposal Options. Electrical World 205, 56–57Google Scholar
- Woodward-Clyde Consultants (1994): Report on Combustion By-Products in Florida. Provided courtesy of the Florida Electric Utility Coordinating Group, Tallahassee, FLGoogle Scholar
- Khandekar MP, Bhide AD, Sajwan KS (1999): Trace Elements in Indian Coal and Coal Fly Ash. Biogeochemistry of Trace Elements in Coal and Coal Combustion Byproducts. Sajwan KS, Alva AK, Keefer RF (eds), Kluwer Academic/Plenum Publishers, New York, NYGoogle Scholar
- Mukherjee AB, Kikuchi R (1999): Coal Ash from Thermal Power Plants in Finland. Biogeochemistry of Trace Elements in Coal and Coal Combustion Byproducts. Sajwan KS, Alva AK, Keefer RF (eds), Kluwer Academic/Plenum Publishers, New York, NYGoogle Scholar
- International Organization of Standardization (ISO) (1997): Environmental Management — Life Cycle Assessment — Principles and Framework. International Organization of Standardization, Geneva, Switzerland (International Standard ISO 14040:1997(E)). [26a] Goal and scope definition and inventory analysis. [26b] Lifecycle impact assessment. [26c] Life cycle interpretationGoogle Scholar
- Goedkoop M, Oele M (2001): SimaPro Database Manual. PRé Consultants, Amersfoot, The NetherlandsGoogle Scholar
- Spath PL, Mann, MK, Kerr DR (1999): Life Cycle Assessment of Coalfired Power Production. National Renewable Energy Laboratory, Golden, COGoogle Scholar
- Kim S, Dale D (2005): Life Cycle Inventory Information of the United States Electricity System. Int J LCA 10(4) 294–304Google Scholar
- Di X, Nie Z, Yuan B, Zuo T (2007): Life Cycle Inventory for Electricity Generation in China. Int J LCA 12(4) 217–224Google Scholar
- U.S. Environmental Protection Agency (U.S. EPA) (2003a): Emissions Data and Compliance Reports. Clean Air Markets-Progress and Results. Washington, DC, 〈http://www.epa.gov/airmarkets/emissions/index.html〉 (accessed March 3, 2003)
- U.S. Environmental Protection Agency (U.S. EPA) (2003b): Toxics Release Inventory (TRI) Program. Washington, DC, 〈http://www.epa.gov/tri/〉 (accessed March 16, 2003)
- May J, Brennan D (2003): Application of Data Quality Assessment Methods to an LCA of Electricity Generation. Int J LCA 8(4) 214–225Google Scholar
- U.S. Environmental Protection Agency (U.S. EPA) (2003): Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2001. U.S. Emissions Inventory 2003, Washington, D.C. 〈http://yosemite.epa.gov/oar/globalwarming.nsf/content/ResourceCenterPublicationsGHG EmissionsUSEmissionsInventory 2003.html〉 (accessed February 19, 2003)