Flotation of sulfide lead-zinc ores of the Akzhal deposit

Abstract

Ore samples from various sections of the underground mine at the Akzhal deposit were studied. The ore mineralization is relatively evenly distributed and is represented by pyrite, sphalerite, and galena. Studies were carried out to reduce the zinc content in the lead concentrate during selective flotation of sulfide lead-zinc ores. The possibility of adjusting the reagent regime using a mixture of zinc sulfate and sodium thiosulfate was studied. The findings indicate the optimal grinding fineness of 62 % –0.074 mm. This value ensures the most acceptable process indicators: the mass fraction of lead in the lead concentrate of 13.19 % with the recovery of 94.89 % and the mass fraction of zinc of 5.36 % with the recovery of 26.65 %. The mass fraction of zinc in the zinc concentrate is 26.54 % with the recovery of 54.41 %. Closed-cycle flotation of lead-zinc ore was conducted using 2 : 1 and 5 : 1 zinc sulfate and sodium thiosulfate mixtures as a depressant for zinc minerals in the lead cycle. With the first ratio, the mass fractions in the lead concentrate were 69.23 % for lead and 8.52 % for zinc and the mass fractions in the zinc concentrate were 57.60 % for zinc and 1.65 % for lead. With the second ratio, the mass fractions in the lead concentrate were 68.12 % for lead and 9.12 % for zinc (compare with 10.10 % with the plant inhouse reagent regime). The mass fractions in the zinc concentrate were 56.80 % for zinc and 1.72 % for lead.