| 摘要 |
<p>K2O-yield is improved and K2O-content of sylvite obtained is raised by process where crude ground K salt containing MgSO4 and clay is (a) electrostatically separated into fractions (1) kieserite and/or long bainite and (2) sylvite, rock salt and clay, and (1) is evacuated; (b) fraction (2), consisting of "quasi-sylvinite" containing adherent short-chain 4-12C fatty acids from (a), is separated by flotation with addition of high molecular sludge-blocking agents, particularly guar meal and starch, into fractions (3) consisting of enriched clay with small residual sylvite content up to 29% K2O, which is carried out, and (4) sylvite and rock salt; (c) fraction (4) is separated with sylvite-flotation agents into (5) consisting of sylvite and pre-concentrate with at least 46% (50%) K2O and (6) rock salt; (d) and fraction (5) if necessary is separated by further flotation into (7) sylvite with at least 60% K2O at K2O-yield over 90%, and evacuated.</p> |
