STUDY ON THE MINERAL PROCESSING TECHNOLOGY OF LOW-GRADE REFRACTORY LEADZINC OXIDE ORES CONTAINING ARGILLACEOUS AND CARBONATED GANGUE IN YUNNAN

摘要

Both sandstone and limestone ores, investigated in this paper, are two types of low-grade complexlead-zinc oxide ores from Yunnan province, China. Because of higher acid consumption (H2SO4250 kg/t for sandstone ore and 450 kg/t for limestone ore) and lower efficiency of liquid-solidseparation, the process to handle these two types of ores has been a challenge. Although wetmetallurgy can be considered, the high cost and low revenue limit this technology to be putinto practice in large-scale. In order to solve this problem, a new technology combining mineralprocessing method with metallurgy technique is studied, which is used to process this refractoryore that consists of sandstone ore with 5.84 per cent Zn, 0.95 per cent Pb and limestone ore with6.50 per cent Zn, 0.92 per cent Pb. The results of flotation closed-circuit tests showed that zincand lead can effectively be recovered from two types of the ores by using the reasonable processflowsheet of flotation technology, and high-efficiency regulators and collectors simultaneously. Forsandstone sample, totally 82.48 per cent Zn and 41.19 per cent Pb were recovered from the feedmaterial. For limestone sample, 84.45 per cent Zn and 40.16 per cent Pb were recovered from thefeed material. One merit of this process flow sheet is that the zinc and lead sulfides and oxides canbe recovered in the flotation cells at the different stage and make sure the concentrate products asa good feed for hydrometallurgical technology. This study provided pretty good technical supportfor tapping low-grade refractory lead-zinc oxide ores.