Abstract:In order to solve the problem that the fine dispersion particle size of copper minerals in a large porphyry copper mine abroad and the high content of gangue minerals prone to mudization affect copper recovery, a separation test study was carried out. The research results show that the closed-loop flotation process of “ three rounds of rough selection-centralized classification of coarse and concentrate, re-grinding and re-selection ” is adopted. Under the conditions that the fineness of coarse selection grinding of-0. 074 mm accounts for 62% , the dosage of lime is 1 500 g / t, the dosage of the collector ethylene xanthate for coarse selection Ⅰ + coarse selection Ⅱ = 20 g / t + 10 g / t, the concentration of the flotation pulp is 33% , the flotation time is 3 minutes, and the fineness of coarse concentrate regrinding of-0. 038 mm accounts for 90% . The copper grade of the available copper concentrate is 26. 89% and the recovery rate is 94. 05% . The molybdenum grade of 0. 43% and the recovery rate of 72. 97% are good indicators, achieving the comprehensive recovery of copper and molybdenum.