Bench-Scale Flotation of Insoluble Slimes From Potash Ore

摘要

A part of the Bureau of Mines mission is to help improve the Nation's mineral posture by providing the technology for utilizing low-grade ores. In this regard, laboratory testing by the Bureau of Mines has shown that the removal of insoluble slimes using selective flocculation and flotation is a viable method for treating low-grade potash ores that have a high content of water-insoluble impurities. Results indicated that over 82 percent of the insoluble slimes could be removed from sylvinite ore containing 5 percent water insolubles and 13 percent K sub O by using nonionic or cationic polyacrylamide flocculants and cationic, anionic, and/or nonionic collectors. Subsequent potash flotation recovered 87 percent of the potash in rougher concentrates containing 57 percent K sub O. Sizing and cleaner flotation of the rougher concentrates upgraded the products to 60 percent K sub O. Filtration of the water-leached insoluble-slimes flotation concentrates on a bed consisting of leached insoluble-slimes concentrate mixed with potash flotation tailings recovered 80 percent of the brine. Filtration rates using the mixed bed were nine times faster than filtration rates obtained when the insoluble-slimes flotation concentrates were filtered separately.