关键词: 低品位鳞片石墨, 粗磨, 再磨, 中矿返回

Abstract: Minerals in a low-grade flake graphite ore from Luobei County，Heilongjiang Province，owns complicated dissemination and great hardness.Beneficiation experiments on the representative samples were carried out，in order to high efficiently developing the ore with less costs.The results showed that with the primary grinding fineness of 90.06% passing 0.074 mm，lime (1 000 g/t) as depressor for pyrite，kerosene (460 g/t) as collector for graphite，2^# oil (70 g/t) as frother，the graphite with 13.12% of fixed carbon was treated.High quality graphite concentrate with fixed carbon content of 97.50%，recovery of 90.63% at fineness of 76.70% 0.074 mm was achieved through the closed circuit process of one roughing，five-stage regrinding and reconcentration (the last regrinding product was treated by two consecutive cleanings)，middlings1 discarding，middlings 2 and 3 mixed and then back to the roughing，middlings 4~6 combined with concentrate 1 and then into regrinding 2.The product can reach the standards of GB/T3518-1995.

Key words: Low-grade flake graphite, Rough grinding, Regrinding, Middling returning