Study On The Separation Performance Of Low Grade Phosphate Ore In Haikou Mine

In our country,there are large reserves of phosphate ore resources,but most of them is the low grade and difficult-to-separate ore.The ore sample used in this experiment comes from Haikou phosphate rock in Kunming,Yunnan province.This paper is aimed at the feasibility study of the low grade mixed phosphate rock in Haikou phosphate mine to explore the suitable mineral processing method,to provide technical support for reasonable development of Haikou phosphorus resources.The chemical and mineral composition of the ore was analyzed.The ore was determined to be a low grade mixed phosphate rock.The ores contain low phosphorus,high magnesium and silicon,and low iron and aluminum content.The phosphate minerals are mainly fine crystal,cryptocrystalline and colloidal aggregates as pseudooolitic and clastic forms.It is a difficult-to-separate ore.In this paper,a series of experiments were carried out to find out a suitable new flotation process and flotation reagent system,and to obtain a phosphate concentrate to meet the requirements of downstream phosphoric acid production.The main work and achievements of the thesis are as follows:1.The fineness of flotation experiment was determined to be 91.60%-0.074mm by the grinding fineness test.Particle analysis of the ground ore found that phosphate was concentrated mainly in the-0.0308mm size ranges.It is suggested that fine grinding is necessary for the treatment of this type of phosphate rock,and the key to obtain better flotation performance is to enhance the flotation condition for fine particles.2.Two processes were tested for the low-grade mixed phosphate rock in Haikou phosphate mine.Under grinding fineness of 91.60%-0.074mm,and a flotation feed of P₂O₅ content of 15.15%,MgO content of 6.15%,the optimal dosage of various reagents and flotation times were determined.The results are as follows:a)with process A:using flowsheet of one roughing,one scavenging direct flotation and one roughing reverse flotation at ambient temperature,a final concentrate with mass pull of 37.59%,P₂O₅ grade 30.08%,MgO grade 1.14%could be obtained at a recovery of74.85%.b)with process B:using flowsheet of only one roughing direct flotation and one roughing and one scavenging reverse flotation at ambient temperature,a final concentrate with mass pull of 44.65%,P₂O₅ grade 28.16%,MgO grade 1.66%,could be obtained at a recovery of 83.04%.Both flotation processes are at ambient temperature and open-circuits.The processes are simple,easy to operate,and meet the expected phosphorus concentrate specification.The test results are repeatable,and the flotation performance is stable and reproducible.3.By studying the sedimentation of the flotation concentrate and tailings,it is concluded that anionic flocculant xn-01 is the best one for the sedimentation of flotation products.