title: Chemical characterization of high-temperature arc gasification slag with a focus on element release in the environment.
abstract: High-temperature arc gasification (HTAG) has been proposed as a viable technology for the generation of energy and the production of saleable byproducts from municipal solid waste (MSW). Total concentrations of elements in HTAG slag were assessed and indicated a high partitioning of trace elements (Pb, Cd, and As) into the flue gas, an issue of concern when assessing the air pollution control residues (APCR) status as a hazardous waste. Hazardous waste leaching tests [such as the toxicity characteristic leaching procedure (TCLP)] were performed and confirmed that the slag did not meet U.S. criteria for a hazardous waste. Leaching was assessed using batch and column tests; the results revealed that Sb and Al were elevated in respect to risk-based regulatory thresholds. Slag samples were carbonated to simulate weathering effects, and although leachable concentrations of Al did decrease by an order of magnitude, Sb concentrations were found to increase. Low total concentrations of certain trace elements (As, Cd, and Pb), with respect to MSW incineration bottom ashes support the potential for reuse of HTAG slag; however, leaching of elements (Pb, Al, and Sb) in batch and column tests indicate that proper engineering controls would need to be taken to ensure protection of water supplies in a reuse application.
authors.affiliation: Department of Environmental Engineering Sciences, University of Florida , Post Office Box 116450, Gainesville, Florida 32611-6450, United States.
authors.forename: Justin G
authors.initials: JG
authors.lastname: Roessler
authors.forename: Wesley N
authors.initials: WN
authors.lastname: Oehmig
authors.forename: Nawaf I
authors.initials: NI
authors.lastname: Blaisi
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Townsend
mesh_terms: D002254:Carbonates / Q000737:chemistry; D004602:Elements; D004777:Environment; D005740:Gases / Q000737:chemistry*; D006256:Hazardous Waste / Q000032:analysis; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D062611:Solid Waste; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity
chemical_list: D002254:Carbonates; D004602:Elements; D005740:Gases; D006256:Hazardous Waste; D062611:Solid Waste; D014874:Water Pollutants, Chemical