Abstract: There are such elements as phosphorus,calcium,chlorine，and fluorine in tungsten and molybdenum beneficiation wastewater.Firstly,calcium oxide was added under the reaction conditions of 45 ℃,200 r/min,and 3 h.The fluorine of wastewater was basically removed and the phosphorus-containing deposit would be obtained by filtration.Secondly,with the conditions of 50 ℃,600 r/min,and 1 h,other solid product would be obtained after calcium oxide was added in the filtrate\[m(CaO)∶m(H₂O)=1∶4\].The residual solution was recycled and returned to beneficiation process.XRD results showed that the solid products were calcium fluoride,calcium fluophosphate,and calcium hydrophosphate in the first stage.In the second stage there was calcium hydrogen phosphate dihydrate.It is showed that phosphorus recovery could be up to 99%,and the resource utilization can be achieved for the wastewater from the molybdenum-tungsten beneficiation process.

Key words: beneficiation wastewater, defluorination, feed-grade calcium hydrophosphate