| Fluorite is the main source of fluorine and an important strategic mineral resource in our country.It is also known as the"second rare earth".Especially in recent years,with the rapid development of new energy and new materials,the demand for fluorine is increasing.However,the high-grade,easy-to-select,and single-type fluorite ore in my country has basically been fully exploited.How to make good use of the associated fluorite ore has become a major problem in fluorite separation.Choice is critical,water glass and its derivatives are currently the most widely used fluorite depressant in the industry.In this paper,related research is carried out on the acidified water glass of calcite depressant,mainly to study the factors affecting the formation time of acidified water glass gel,and to form a new depressant on the basis of it.The flotation separation effect of the new depressant on fluorite and calcite was studied,and the mechanism of action of the new depressant on fluorite and calcite was studied by using contact angle,mineral surface potentiodynamic analysis,mineral infrared spectrum analysis and mineral surface adsorption test.The test results of acidified water glass gel demonstrate that:within a certain range,the longer the synthesis time of acidified water glass,the higher the modulus of water glass,the higher the content of sulfuric acid,the higher the concentration of acidified water glass and the greater the hardness of water,the longer it takes to acidify water glass gel.shorter.After the configured acidified water glass is permitted to stand for a period of time,the flotation effect of fluorite and calcite is excellent.Meanwhile,the generation of gel will involve the separation of fluorite and calcite by acidified water glass.The time needed for the formation of the gel of the three new agents is longer than that of acidified water glass,which prolongs the use time of the agents.The single-mineral test results show that sodium oleate cannot separate fluorite and calcite well without adding depressant.When acidified water glass is used as an depressant,the flotation separation effect is the best when the pH value is about 7,the modulus is 2.4 to 2.7,the acidification ratio is 1:1,and the amount of acidified water glass is 600g/t.the recovery rates of fluorite is 96.1%,and calcite was 28%.When SS-1,SS-2 and SS-3 are used as depressant,under neutral conditions,when the depressant dosage is 600g/t,the flotation effect is the best,and the recovery rates of fluorite are96.96%,97.13%,and 94.58%,respectively,calcite recovery rates were 10.64%,18.5%,9.55.Sort by flotation separation effect:SS-1>SS-3>SS-2>acidified water glass,SS-1has better flotation separation effect on fluorite and calcite than the other three depressant.And compared with acidified water glass,SS-1 can further improve the recovery rate of fluorite flotation.The test results of the actual ore of high calcium fluorite show that the selective depression effect of the three combined depressant on the actual ore is better than that of acidified water glass,and the depressant SS-1 has the best flotation effect.When the pH is about 8,the amount of sodium oleate of the collector is 400g/t,and the amount of depressant SS-1 is 4000g/t,the effect of a roughing test is the best.At this time,the grade of CaF2 is 88.99%,and the recovery rate is 93.60%.After the closed-circuit process of"one roughing,one sweeping and eight refining stages",the first stage grinding and coarse concentrate regrinding are respectively-0.074mm,accounting for51.5%and 74.05%,neutral conditions,and depressant 4000g/t,collector 400g/t,the obtained fluorite concentrate grade reaches 97.86%,the recovery rate reaches 89.59%,and the flotation index is excellent.The mineral depressant mechanism shows that:after adding sodium oleate,the contact angles of fluorite and calcite increase at the same time,but after adding SS-1,the contact angle of fluorite increases and the contact angle of calcite decreases,indicating that the addition of SS-1 can increase the hydrophobicity of fluorite.and calcite hydrophilic,so as to achieve the separation of the two.After adding depressant SS-1,the surface potential of fluorite moved to the negative direction with a small amplitude,while the potential of calcite moved to the negative direction greatly.O vibration peak appears.Both patenting and infrared spectroscopy tests showed that SS-1 had little effect on fluorite,but was adsorbed on the surface of calcite by chemical adsorption,thereby inhibiting the flotation of calcite.The adsorption test results showed that the adsorption amount of SS-1 on the surface of fluorite was very small,but a large amount of adsorption on the surface of calcite hindered the interaction between calcite and collectors and inhibited the flotation of calcite.best effect. |
