Study On Characteristics Of Dense Medium Suspension And Fine Fluorite Discarding Test

With the exploitation and utilization of fluorite minerals in our country,poor,fine and miscellaneous have become the main characteristics of fluorite minerals.How to effectively discard the tailings of fine fluorite slime has become an urgent problem to be solved.In this paper,ferrosilicon aggravated and 1-0.25mm fluorite slime are taken as research objects.Through the grading test of 270D ferrosilicon powder,more fine ferrosilicon aggravated quality is obtained.The variation trend of rheological properties and stability of pure medium suspension with density of 2.1 g.cm^-3-2.6 g.cm^-3 was investigated.The tailing test of 1-0.25mm fluorite slime was carried out to study the effects of four factors,i.e.aggravated particle size,suspension density,diameter of underflow orifice and inner diameter of overflow center,on the tailing effect.Taking the recovery rate as the main evaluation index and considering the comprehensive efficiency,the optimal level combination was selected,and the better tailing effect was obtained.The tailing effect proves that the heavy medium suspension with D50=17.12?m is more advantageous to the tailing of 1-0.25 mm fluorite slime under the experimental conditions.The experiment of ferrosilicon aggravated grading shows that the aggravated particle size of dense medium suspension decreases with the increase of test time.The proportion of aggravated particles in suspensions of#1?D50=24.95?m?,#2?D50=17.12?m?and#3?D50=5.21?m?is larger.The dominant particle size of the suspension is decreasing,but the proportion of the suspension is increasing gradually.With the increase of test time,the particle size dispersion of the aggravated particles in each suspension increases gradually.In the tailing test of fluorite slime,the feeding pressure is 0.06MPa,the concentration of fluorite slime is 50g/L,and the feeding grade is 1-0.25mm.Orthogonal tail throwing test was carried out.The recovery rate was the main evaluation index by range analysis of orthogonal test,and comprehensive efficiency was taken into account.The optimal scheme was chosen as follows:the D₅₀ level of tail throwing dense medium suspension was17.21?m,the density level was 2.1g.cm^-3,the diameter level of bottom outlet was 20 mm,and the diameter level of overflow center was 19 mm.The yield of overflow products was 15.85%,and the CaF₂ grade of overflow products was 10.45%.In the fine fluorite heavy medium tailing test,the variance analysis of test data shows that the change of aggravated particle size has no significant effect on the density difference of bottom overflow suspension.The variation of suspension density level has a significant effect on the density difference of bottom overflow suspension.The diameter of underflow orifice has a certain influence on the density difference of underflow suspension.The diameter of overflow pipe has a significant effect on the density difference of bottom overflow suspension.The orthogonal experiment range analysis was used to evaluate the density difference of bottom overflow suspension,the recovery rate of CaF₂ from fluorite slime and the comprehensive efficiency of tail throwing.Among these factors,the aggravation of particle size,the diameter of underflow orifice,the diameter of overflow center pipe and the density of dense medium suspension were considered.The density of suspension is the most important factor in the tail throwing test of fluorite slime dense medium cyclone.