The invention discloses a technology of enhanced-dispersion partial selective and bulk flotation of lead and
zinc sulfide ores under low and high
alkalinity. During grading of the lead and
zinc sulfide ores,
sodium hexametahposphate is taken as a dispersion agent and directly added into a
ball mill, the ores are ground till the ores with the size of 0.074mm account for 67%-70%,
lime is taken as an adjusting agent,
zinc sulfate and
sodium sulfite are taken as inhibitors, dithiophosphate BA and diethyldithiocarbamate are taken as collectors, and selective flotation of part of lead minerals with good floatability can be performed under low
alkalinity; then
xanthate and the diethyldithiocarbamate are taken as collectors, and the flotation of the lead minerals is further performed under high
alkalinity;
copper sulfate is added in lead flotation
tailings for activation, butyl
xanthate is further taken as the collector for flotation of zinc blende and part of
pyrite, and zinc-
sulfur separation flotation is further performed on zinc-
sulfur mixed concentrate; and
sulfuric acid is added in zinc flotation
tailings for activation, and the
xanthate is taken as the collector for flotation of the remaining
pyrite. By adopting the technology, the lead-silver
recovery rate can be improved, the using amount of
lime and
sulfuric acid can be reduced, the circulating amount of middlings can be reduced, the ore dressing cost can be reduced and the grade of the concentrate can be improved.