Research On Flotation Of Fluorite From A Scheelite Tailings

The associated fluorite resources represented by scheelite are very rich in China,but this part of the fluorite mine has not yet been fully utilized due to the technical limitations.This paper took a scheelite tailings in Hunan as the research object,and adopted a new type of collector named PJ to float fluorite which achieved good results.By pure mineral flotation test,this paper compared the flotation behavior of fluorite,quartz and calcite in different reagent systems.Infrared spectroscopy,Adsorption capacity,Zeta potential,and mineral surface dissolution calculations were used to analyze the mechanism of fluorite flotation process.The results of pure mineral flotation test showed that the new collector PJ has good collect ability and selectivity,which can replace the traditional collector of fluorite such as sodium oleate.Acidic water glass has a strong inhibitory effect on calcite,but it has less effect on fluorite,so it can be used as a depressor in fluorite cleaning.Some common metal cations in pulp are not conducive to the separation of fluorite and gangue and are harmful ions.Under the optimal reagent system,the fluorite in the scheelite tailings which the grade of CaF₂ is 23.87%was recovered,we can obtained the qualified fluorite concentrate which the grade is 96.38%and the recovery is 61.64%by the circuit flotation flowsheet of single-stage roughing,two-stage scavenging,regrindingthe rough concentrate and seven-stage cleaning.Actual mineral test results showed that the new collector PJ has a good collect ability and selectivity,and can be used as an excellent collector in fluorite flotation.The results of the mechanistic study showed that the collector PJ and acidic water glass are both adsorbed on the surface of fluorite and calcite,the surface of fluorite was mainly adsorbed by PJ,the surface of calcite is mainly adsorbed by acidic water glass.PJ had no adsorption on the surface of quartz well acidic water glass can adsorpt on the quartz surface.After PJ adsorption,the decrease in surface potential of fluorite is larger than that of calcite,that is,the adsorption of PJ on fluorite surface is more than that of calcite,and the surface potential of quartz is almost unchanged.The effect of acidic water glass on the surface potential of calcite and quartz is much larger than that of fluorite,so the acidic water glass has a larger adsorption capacity on calcite and quartz than fluorite.Mineral surface dissolution studies showed that pH affects the adsorption of the collector on the mineral surface.In the acidic environment,the collector PJ adsorbed on the surface of fluorite and calcite by the opposite sex and is physical adsorption.In the alkaline environment,the collector PJ adsorbed on the surface of fluorite and calcite through chemical bonds and action,which is chemical adsorption.The pH and ion concentration in the solution affect the mutual transformation of the mineral surface.Under ideal conditions,calcite is adsorbed on the fluorite surface at pH>8.When pH<8,fluorite is adsorbed on the surface of calcite.When the ion concentration in the solution satisfies lg[CO₃^2-]>2lg[F^-]+2.06,calcite is adsorbed on the fluorite surface.When lg[CO₃^2-]<2lg[F^-]+2.06,fluorite is adsorbed on the surface of calcite.