Separation of flue-gas scrubber sludge into marketable products. First quarterly technical progress report, 1 September, 1993--30 November, 1993
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. The vast majority of the sludge is simply landfilled, but with increasing landfilling costs this can cost the plant millions of dollars per year. Producing marketable materials from the sludge is a far more promising avenue, provided that the products can meet the necessary specifications at a reasonable cost. This project is investigating the surface properties of scrubber sludge, particularly of the calcium sulfite, since the surface chemistry of this material has never been studied in detail. Knowledge of these properties is critical for the development of a process that can produce a high-quality calcium sulfite or gypsum product while keeping process costs low enough that the material produced will be competitive with that from other, more conventional sources. This purification will consist of minimal-reagent froth flotation, using the surface properties of the particles of unreacted limestone to remove them and their associated impurities from the material, leaving a purified gypsum or calcium sulfite product. The separated limestone will be a useful by-product, as it can be recycled to the scrubber, thus boosting the limestone utilization and improving process efficiency. Calcium sulfite will then be oxidized to gypsum, or separated as a salable product in its own right from sludges where it is present in sufficient quantity. The main product of the process will be either gypsum or calcium sulfite, depending on the characteristics of the sludge being processed. These products will be sufficiently pure to be easily marketed, rather than being landfilled.
- Research Organization:
- Michigan Technological Univ., Houghton, MI (United States). Dept. of Metallurgical and Materials Engineering
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- FG22-93PC93214
- OSTI ID:
- 10132597
- Report Number(s):
- DOE/PC/93214-T1; ON: DE94008086; BR: AA1525050; TRN: AHC29406%%33
- Resource Relation:
- Other Information: PBD: Dec 1993
- Country of Publication:
- United States
- Language:
- English
Similar Records
Separation of flue-gas scrubber sludge into marketable products
Separation of flue-gas scrubber sludge into marketable products. Quarterly technical progress report No. 12, June 1, 1996--August 30, 1996
Related Subjects
01 COAL, LIGNITE, AND PEAT
WASTE PROCESSING PLANTS
SLUDGES
WASTE PRODUCT UTILIZATION
SURFACE PROPERTIES
GYPSUM
CALCIUM COMPOUNDS
FOSSIL-FUEL POWER PLANTS
FLUE GAS
DESULFURIZATION
SULFITES
WASTE MANAGEMENT
PROGRESS REPORT
200202
010800
NOXIOUS GAS AND PARTICULATE EMISSIONS