Open AccessSeparation of flue-gas scrubber sludge into marketable products. Quarterly technical progress report, March 1, 1996--May 31, 1996
Author(s) -
S K Kawatra,
T C Eisele
Publication year - 1996
Language(s) - English
Resource type - Reports
DOI - 10.2172/383051
Subject(s) - flue gas desulfurization , scrubber , lime , flue gas , gypsum , sulfur dioxide , chemistry , sulfur , waste management , sodium sulfite , sulfate , sulfite , coal , environmental chemistry , inorganic chemistry , sodium , metallurgy , materials science , organic chemistry , engineering
To reduce their sulfur emissions, many coal-fired electric power plants use wet flue-gas scrubbers. These scrubbers convert sulfur oxides into solid sulfate and sulfite sludge, which must then be disposed of. This sludge is a result of reacting limestone with sulfur dioxide to precipitate calcium sulfite and calcium sulfate. It consists of calcium sulfite, gypsum, and unreacted limestone or lime, with miscellaneous objectionable impurities such as iron oxides, silicates, and magnesium, sodium, and potassium oxides or salts. These impurities prevent many sludges from being utilized as a replacement for natural gypsum, and as a result they must be disposed of in landfills, which presents a serious disposal problem