Potash recovery from process and waste brines by solar evaporation and flotation.
Foot-DG Jr.; Huiatt-JL; Froisland-LJ
Salt Lake City, UT: U.S. Department of the Interior, Bureau of Mines, RI 8911, 1984 Jan; :1-27
The Bureau of Mines investigated energy-efficient methods for recovering potash values from process and waste brines. Laboratory pan evaporation of four chloride brines produced crude salts containing predominantly sylvite, halite, and carnallite. Six sulfate-chloride brines produced crude salts containing primarily schoenite, kainite, leonite, sylvite, carnallite, and halite. Potash grades ranged from 7.2 to 22.2 pct K2O, and recoveries from 84 to 99 pct. Sylvite flotation from chloride evaporites, with amine collector, recovered 90 to 97 pct of the potash in a concentrate containing 54.3 to 60.3 pct K2O. Fatty acid flotation of the high-sulfate evaporite recovered 78 pct of the sulfate minerals in a 27.8-Pct-K2O concentrate. Flotation of the chloride minerals with amine collector recovered 80 pct of the potash in a 59.7-Pct-K2O concentrate. Solar evaporation of 10,000 gal of brine recovered 99 pct of the potash in a crude evaporite containing 24.5 pct schoenite and 20 pct sylvite. Continuous flotation in a 100- lb/h process research unit recovered over 95 pct of the potash in schoenite and sylvite concentrates containing 28.0 and 62.3 pct K2O, respectively. An economic evaluation suggested a rate of return of 3 pct for a new facility and 9 pct if the process is adapted to fit an existing plant.
Materials recovery; Brines; Flotation; Potash deposits; Evaporation; Beneficiation; Design criteria; Solar energy; Industrial wastes; Economic analysis; Capitalized costs; Operating costs
IH; Report of Investigations
NTIS Accession No.
Salt Lake City, UT: U.S. Department of the Interior, Bureau of Mines, RI 8911