| 摘要 |
Tin values in the form of cassiterite (SnO2) are recovered from aqueous pulps of finely divided cassiterite-bearing ore, preconcentrate or concentrate by froth flotation. The ore pulps are deslimed thoroughly, partially or not at all. Slimes, gangue or waste minerals in the pulps are selectively depressed by use of a metal salt/silicate reagent combination. The cassiterite is floated at a mildly acidic to neutral pH, generally in the range of about 5 to 6, by one and/or more highly selective tin collectors such as sulfosuccinamates, aspartates, phosphonates, etc., at environmental or, preferably, elevated pulp temperature. Flotation machine impeller speeds are within conventional range or higher, preferably the latter. The cleaning of the thus-produced cassiterite rougher flotation concentrate is performed after an additional (secondary) conditioning step whereby an additional depressant, such as tannic acid, sulfuric acid, sodium fluosilicate, sodium lignin sulfonate or activated charcoal is used. |
