The invention discloses a low-
alkalinity flotation
separation method for
pyrite activated by Cu2+ and
chalcocite. The method comprises the steps that
lime is firstly added in the ore
grinding stage so as to keep low
alkalinity, a composition of
citric acid,
sodium sulfite and pyrogallic acid is added as a composite inhibitor in the rougher flotation stage to inhibit the
pyrite,
copper rougher flotation is achieved under the condition of low
alkalinity, then a dispersing agent is added for concentration, inhibition on
gangue minerals is intensified, and
copper concentrates are obtained. Compared with the traditional manner of inhibiting
sulfur through
lime, the inhibition effect of the composite inhibitor on the
pyrite activated by Cu2+ is remarkable, wherein
citric acid is used for removing the
activation action of Cu2+ on the pyrite, so that natural floatability of the pyrite is restored, the inhibition effect on the pyrite is intensified through
sodium sulfite and pyrogallic acid, meanwhile, the phenomenon of trough moving caused by foam
viscosity is eliminated, and the index of the
mineral processing technology is improved; and in addition, due to the fact that the flotation pH value is lowered, recycling of associated gold in ore is facilitated.