Experimental Study On Classified Flotation Of Low-grade Siliceous Colloidal Phosphate Rock In Jinning, Yunnan

Phosphate ore is a strategic non-metallic mineral resource,which occupies a very important position in the national economy.China is rich in phosphate ore,and the volume of annual mining is huge.With the continuous mining,the rich ore decreases,and the poor,fine and miscellaneous problems of phosphate ore are increasingly prominent.In this study,siliceous collophanite ore of middle and low grade from Jinning mine was used as raw material,and a reasonable flotation process was determined according to different particle size by using the method of grading flotation,and better process indexes were obtained.The results show that the grade of P₂O₅,Mg O,Si O₂and sesquioxide(Al₂O₃+Fe₂O₃)is19.98%,1.10%,37.37%,4.17%respectively.The particle size screening and analysis results is that with the ore particle size becoming smaller,P₂O₅ grade first increases and then decreases,and P₂O₅mainly enriches in the coarse particle size.The double reverse flotation process is adopted for the coarse particle size of+0.038mm,and open circuit test results illustrate that the the grade of P₂O₅is 30.20%in phosphorus concentrate,and the recovery is60.84%,with the content of Mg O and Si O₂ being 0.29%and 21.19%,besides the desilication rate is 69.03%.The direct and reverse flotation process is used for the fine particle size of-0.038mm.The fine particle size flotation indexes of phosphorus concentrate with grade and recovery of P₂O₅ of 30.45%and 67.90%,with the content of Mg O and Si O₂ being 0.48%and 18.10%can be obtained through the open circuit test.The problem of desilication foam stickiness in concentrative separation can be effectively solved by using the grading-flotation process,which saves the cost of reagents and provides a technical path for the effective utilization of middle and low grade siliceous collophanite ore.