Abstract: According to the characteristics of the flotation tailings of phosphorite in Guizhou in which the main mineral is dolomite and fluorine apatite, reseparation research between dolomite and fluorine was done by the reverse flotation of one roughing and one cleaning after grinding. The results show that at these optimal conditions which are: 62.50%-75 μm grinding size, 14 kg/t phosphoric aid as inhibitor, 300 g/t AB as collector for roughing and 100 g/t for cleaning. The phosphorous concentrate with a content of P₂O₅ for 22.29%, MgO for 4.23% and recovery of P₂O₅ for 56.72%, and the magnesium concentrate with a content of P₂O₅ for 5.68%,MgO for 19.97% and recovery of MgO for 93.38% can be obtained. It provides an economic and feasible way for comprehensive utilization of the tailings.

Key words: Tailings of Phosphate ore, Reverse flotation, Phosphorous concentrate, Magnesium concentrate