Chemistry of inorganic compounds – Sulfur or compound thereof – Oxygen containing
Patent
1991-09-27
1994-11-08
Straub, Gary P.
Chemistry of inorganic compounds
Sulfur or compound thereof
Oxygen containing
23293A, 23313R, 264109, 106786, 423170, C01F 1146
Patent
active
053624718
ABSTRACT:
This invention relates to an improved process for producing gypsum calcium sulfate dihydrate flakes from powdered gypsum calcium sulfate dihydrate obtained from the desulfurization of flue gas by the wet limestone process. The flakes have sufficient size and strength such that the gypsum calcium sulfate dihydrate can be handled and processed in conventional equipment commonly used by wallboard manufacturers and others in the construction industry, The intermediate calcium sulfate dihydrate from the desulfurization process is dewatered to about 5 to 12% by weight and then compressed into a thin sheet under a compaction or compression load of 4 tons force to 15 tons force per linear inch of sheet width. A linear speed of from 0.5 to 2.5 feet per second is maintained during compaction providing a compaction residence time of from about 0.2 to 1.2 seconds. An elevated temperature is maintained during the compaction process to enhance the reformation of the crystal size and shape of the gypsum calcium sulfate dihydrate. The combination of pressure and temperature on the moist gypsum calcium sulfate dihydrate alters the physical characteristics of the gypsum calcium sulfate dihydrate, thereby resulting a sheet which breaks into hard flakes on exit from the compaction zone.
REFERENCES:
patent: 3497321 (1970-02-01), Decker et al.
patent: 3779686 (1973-12-01), Kerttula et al.
patent: 3820970 (1974-06-01), Watkins
patent: 4173610 (1979-11-01), Huller et al.
patent: 4239716 (1980-12-01), Ishida et al.
patent: 4377414 (1983-03-01), Buschmann et al.
patent: 4544542 (1985-10-01), Angevine et al.
patent: 4954134 (1990-09-01), Harrison et al.
patent: 5121683 (1992-06-01), Biefeldt
patent: 5154874 (1992-10-01), Koslowski
"Agglomeration: Growing Larger in Applications and Technology" by Jon E. Browning in Chemical Engineering, 4, Dec. 1967 pp. 147-169.
Gagliardi Carmine R.
Roth Timothy J.
Welliver William R.
Air Products and Chemicals Inc.
Brewer Russell L.
Marsh William F.
Straub Gary P.
Vanoy Timothy C.
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