Study On Separation-enrichment Of Polymineral And Preparation Of Construction Ceramics Of Xinhua Molybdenum Tailings

Mining is one of the important industries of national economy in our country,at the same time of mining development,therealso has the problem of tailings discharge.The huge amounts of tailings annually has Put forwards the greate challenge to utilizite efficiently.The comprehensive utilization has become major issues to be resolved toprotect the ecological environment and eliminate the tailings hidden trouble in China.In this paper,study on separation-enrichment of polymineraland highly efficient use has been carried out to Xinhua molybdenum tailings.The molybdenum tailings cascade processing plan has been determined by laboratory experimentsaccording to the analysis of minerals composition and chemical composition.Separation and enrichment of polymineraland use the effective components to prepare high-performance molybdenum tailings ceramic has been finished.This thesis also discussed molybdenum tailings ceramic sintering mechanism.Xinhua molybdenum tailings is mainly composed of diopside,feldspar,phlogopite,olivine and dolomite,and trace minerals are mainly garnet,rutile,ilmenite,etc..According to the tailings characteristics of mineral composition complex and more trace mineral components,molybdenum tailings comprehensive utilization mode has been the proposed of high content and high valuemineral componentsseparation and enrichment firstly,then the largest proportion of non-metallic mineral as ceramic raw materials to use.Sorting process of magnetic separation-flotation-grinding-flotation-magnetic separation has been determined to separate and enrich more minerals of molybdenum tailings.The yield of phlogopiteis 10.86%,the recovery is 64.93%,the grade is 8.93%.The yield of magnetic mineralis 5.68%,the recovery is 77.14%,the grade is 45.63%.The yield of pyriteis 4.09%,the recovery is 81.73%,the grade is 34.7%.The yield of calciteis 7.05%,the recovery is 78.77%,the grade is 46.31%.The yield of dolomiteis 12.45%,the recovery is 64.5%,the grade is 16.44%.After more minerals separation and enrichment,its main components of tailings is close to the ceramic billet mineral components,which could be as the main material to prepare molybdenum tailings ceramic with good alkali resistance.Samples were tested by X-ray diffraction(XRD)and scanning electron microscopy(SEM),and also the influence factors of molybdenum tailings ceramic firing were analyzed.The best formula as molybdenum tailings:illite:quartz=65:15:20,at the sintered temperature 1165?1170?,residence time 120 min,the prepared sample exhibited the following properties of waterabsorption0.42?0.43%,apparent porosity 0.956?0.958%,bulkdensity 2.23?2.26g/cm3,bendingstrength46.34?46.85MPa,which is up to the National Standard of China.Results of Crystallization dynamics showed that thegraingrowthexponent is 2.23,the overall crystallization is dominated.Thesinteringactivationenergy is 99.77kJ/mol,which is interpretedthat the molybdenum tailings ceramicis easy tosinterand the densification is controlledbydiffusion.Through analysis of TG-DTA,SEM,XRD,it is concluded that it is early stage for molybdenum tailings ceramic sintering before 800?,which is controlled by solid phase surface diffusion and mass transferring.After 800?,it is intermediateandfinalstage,which is controlled by particle rearrangement and plastic flow,sintering temperature is tend to lowtemperature.