| Tin is a strategic metal resource in China.With the gradual depletion of highquality primary tin resources,new challenges have been put forward for the efficient recycling of refractory tin resources.In this paper,aiming at the tin oxide ore in Datun mining area of Yunnan Tin Group,according to the on-site beneficiation process,the process test research is carried out to solve the problems of low recovery rate of tin gravity separation and low utilization rate of tailings in the production process.In this paper,the process mineralogy of a pit oxidized ore in Datun mining area of Yunnan Tin Group was studied.The results show that the main minerals in the ore are calcite,dolomite and limonite.Tin minerals are mainly cassiterite,and the symbiotic relationship is simple,only with limonite,calcite,dolomite.Under microscope,cassiterite often adheres to iron mud;when the grinding fineness of the ore is-41.81 %of-200 mesh,the monomer dissociation level of cassiterite is low,and the completely dissociated particles account for 57.62 %.According to the characteristics of the sample and the on-site process flow,the condition test of the grinding fineness of the coarse-grained tin ore of the oxidized ore in a pit was carried out,and the magnetic separation test of iron removal and recovery of iron minerals in the tailings of gravity separation was explored.In addition,the flotation test of φ125mm cyclone overflow was also studied.On the basis of tin grade of about 1.05 % and iron grade of about 14.32 %,the grinding fineness test of shaking table gravity separation was carried out,and the grinding fineness was optimized to achieve tin concentrate grade of 45.17 % and recovery of 55.56 %.The comprehensive grade of qualified tin concentrate and crude tin concentrate in the whole process is15.07 %,and the recovery rate is 82 %.The grade of the three-stage shaking table tailings is 0.043 %,the grade of the sediment tailings is 0.186 %,and the total tailings grade is 0.071 %.Because the ore contains a large amount of iron-containing minerals and has a high density,between cassiterite and gangue,some cassiterite is closely associated with it.Therefore,it is necessary to remove iron before gravity separation,so as to reduce the interference of iron-containing minerals on cassiterite recovery in the process of shaking table separation. |
