Comprehensive assessment of flotation reagents by their influence on metal losses and flotation selectivity

Abstract

The paper proposes a method for quick estimation of the average floatability of minerals according to the kinetic experiment, without finding the flotation spectrum where first moments of distribution are calculated by the coefficients of the polynomial approximation of the kinetic curve in the logarithmic form. An example of copper-nickel ore demonstrated that this method is effective in the multiparameter problem of comparative assessment of reagents. The ten parameters assessed included the average floatability of target minerals (chalcopyrite and pentlandite), pyrrhotite and rock; flotation selectivity coefficients of target minerals relative to pyrrhotite and rock; levels of copper and nickel losses with bulk flotation tailings. Interdependencies of parameters were visualized using diagrams showing the effect of flotation reagents on the groups of parameters: average floatability, selectivity coefficients, metal losses and selectivity relative to rock. The influence of butyl xanthate, aerofloat, diesel fuel, as well as gangue depressants – carboxymethyl cellulose (CMC) and acidified water glass (with a total consumption of collectors, diesel fuel, acidified water glass and CMC of 130 g/t, 5–10 g/t, 200 g/t, and 500 g/t, respectively) on the estimated parameters under collective flotation conditions was determined. It was found that the addition of aerofloat and diesel fuel to the main reagent collector – xanthate – increases the flotation selectivity of pentlandite and chalcopyrite relative to pyrrhotite and rock-forming component. The introduction of acidified water glass into the reagent scheme increases the flotation selectivity of nickel and copper sulfides relative to the rock. CMC additives impair the selectivity of copper flotation. The quantitative effects of each individual parameter were taken into account in the integral rating assessment of the prospects of using reagent combinations for copper-nickel ore by a set of ten parameters. The method proposed can be further used for the mass comparative evaluation of flotation reagents.