Abstract |
The report gives results of experimental studies of the leaching properties and thermal activity of solid residues from the fluidized-bed combustion (FBC) of coal. Means for processing the residues, to reduce the environmental impact of their disposal, are also studied. Previous leaching and thermal activity tests were expanded to include residues from additional experimental FBC units, including both atmospheric and pressurized systems. Leaching tests were conducted on both untreated residues and residue samples processed into a cement-like material. Results indicate that the major potential contaminants in the leachate from the FBC residues are the high pH, total dissolved solids, and sulfate levels, all of which are above drinking water regulations. Heat release when initially exposed to water, due to calcium oxide hydration, may also create a handling problem. Trace metals in the leachate do not generally exceed drinking water regulations. Processing of the residues caused some reduction in leachate contaminant levels. Additional tests on processing and utilizing FBC residues are also reported. |