Experimental Study On Graded Flotation Of Low-grade Phosphate Ore In Jinning

Phosphorus is a non-renewable natural mineral resource and an important chemical raw material.With the increasingly pressing situation of phosphate rock resources around the world,phosphate rock has become a strategic resource.The phosphate rock resources in China are mainly low-grade sedimentary phosphorites,At present,many of China's phosphate ore are characterized by poor,fine,miscellaneous and difficult.This paper is aimed at the problem of low raw ore grade,complex ore components and difficulty in selecting a certain collophanite in the Jinning area.The grading and sorting as the main technical route,and the systematic beneficiation trials has been conducted.A reasonable sorting process was finalized and a qualified beneficiation process index was obtained.In this paper,a variety of process mineralogical detection methods were used to analyze the ore properties of raw ore.The specific mineral composition of the phosphorus ore sample and the mineralogical characteristics of the main minerals were identified.Phosphorus in ore is mainly in the form of fluorapatite,useful mineral P₂O₅ grade of 18.23%.The minerals in the gangue minerals are mainly quartz,dolomite and chalcedony,wherein SiO₂ content of 34.21%,CaO content of 28.19%,MgO content of 2.07%,the ore belongs to siliceous-calcium phosphate rock.The raw ore is ground by pre-screening and grinding,and the appropriate grinding fineness is determined to be-0.074mm with a content of 95.99%.Grinding products are categorized using a wet sieve method to obtain coarse-grained?+0.045mm?and fine-grained?-0.045mm?two-part ore products.The process flow exploration experiments were conducted on coarse-grained and fine-grained ore respectively,and a feasible experimental scheme was preliminarily drawn up.In addition,systematic conditional experiments were conducted on two kinds of raw ore products to determine a reasonable flotation process and an optimal pharmaceutical system.The coarse-grained ore adopts a double reverse flotation process,that is,once roughing for magnesiumremovalanddesiliconizationprocessofonceroughingandonce scavenging,demagnification collector adopts YP6-1,desilicon collector adopts GE-609.The open circuit test index of phosphate concentrate P₂O₅ grade of 29.16%and recovery rate of 47.09%was obtained.The fine-grained ore using positive-reverse flotation process,that is,once roughing and once cleanings for direct flotation,once roughing and once scavenging for reverse flotation,direct flotation collector adopts sodium oleate,reverse flotation collector adopts YP6-1.The open circuit test index of phosphate concentrate P₂O₅ grade of 29.21%and recovery rate of 21.40%was obtained.The closed circuit test of ore was conducted,and the closed-circuit test index of comprehensive phosphate concentrate P₂O₅ grade of 28.58%,total recovery of72.79%and MgO content of 0.83%was obtained.The products can be used for the wet process of phosphorus extraction.The research in this paper has a certain guiding significance for the reasonable development and utilization of low-grade refractory phosphate rock in the region.