Influence of an ionic composition of a sludge liquid phase on technological parameters of beneficiation

The article presents the results of the study on the influence of an ionic composition of a sludge liquid phase on technological parameters of copper-nickel ore beneficiation. A decrease in surface tension on the liquid–gas boundary was found for solutions of sodium, calcium and magnesium chlorides in concentrations of 1 g/l and 5 g/l. The results of the study were used as a basis for proposing the following series of chloride-containing salts in order of reducing surface tension in distilled water: CaCl2 > MgCl2 > NaCl. The minimum value of this parameter is set for sodium chloride in a concentration of 5 g/l — 50.25 mN/m. The study on the effect of frothers on surface tension in distilled water resulted in determining a number of surfactants in order of decreasing surface activity: T66 > T80 > polypropylene glycol monobutyl ether frother (OPSB) > methyl isobutyl ketone (MIBK) > pine oil. A number of frothers have been established as their surface-active properties decrease in the presence of the chloride-containing salts under study in water: T66 > T80 > OPSB > MIBK > pine oil. Regarding the T-66 frother in a concentration of 1% (the consumption rate is 50 g/t), surface tension on the liquid – gas boundary in the presence of chloride-containing salts was 21.56 mN/m. A flotation process using salt solutions (CaCl2, MgCl2, NaCl) showed a decrease in copper and nickel in the flotation concentrate due to the depressing effect of calcium ions. An increase in the extraction of valuable components into the concentrate is correlated with an increase in the surface-active characteristics of frothers in the presence of chloride-containing salts in water due to sodium chloride ions, which probably reduce the depressing effect of calcium ions.