Study On Dephosphorization Of Phosphorus-rich Manganese Ore By Mechanical Beneficiation And Chemical Beneficiation

Most of manganese ore in China contains a rather high grade of phosphorusminerals, which are harmful to iron and steel metallurgy. In recent years, with the rapiddevelopment of steel industry, manganese based ferroalloy and metal manganese yieldin China rapid growth, manganese ore consumption has also been increased, quantity ofrich manganese ore reduced increasingly, it slso makes the proportion of mineral whichcomposition complex and difficult to separate increases day by day, the treatment andresoure utilization of phosphorus-rich manganese ore becoming an urgent problem.Therefore, it is important to improve the security of manganese resources and promotethe sustainable development of mining areas by combining with the comprehensiveutilization of phosphorus-rich manganese ore and study the economical efficiencydephosphorization technology.The basic properties of phosphorus-rich manganese ore which was collected from aplant in Chongqing were studied by various analytic methods in eye of itscomprehensive utilization. Then adopt mechanical beneficiation and chemicalbeneficiation methods to investigate its effectiveness of dephosphorization experimentrespectively, and parameter conditions which play a main role in each stage processwould be discussed.Conclusions are as follows:The phosphorus-rich manganese ore is a kind of brown ore with low water content.Its density is about1.2g/cm³-1.5g/cm³. It is mainly composed of manganese tetra-phosphide phase， manganese carbonate phase, Calcium pyrophosphate phase.Manganese ore mainly contains Mn、P、Ca、Si element, the percentage of them is asfollows: manganese （29.3%），phosphorus （2.7%），calcium （12.3%），silicium （9.7%），ferrum （1.0%），aluminium （0.87%）.The influence of each flotation reagent dosage to manganese recovery，P/Mn ratioand concentrate recovery was discussed in high intensity magnetic-reverse flotationexperiment. The result show that, we can get manganese concentrate which manganese31.3％，phosphorus0.66％，P/Mn ratio0.021after high intensity magnetic test. Thetechnological condition and index to reach a better effect is also discussed. Controllingdosage of oxidized paraffin soap is0.8kg/t，sodium oleate is0.4kg/t，sodium carbonateis6.0kg/t，sodium silicate is2.0kg/t. Using0.2mol/L sulfuric acid leaching phosphorus-rich manganese ore underelectric field first，and then dissolve organophosphorus in fenton-like system by addinghydrogen peroxide，dephosphorization through reverse flotation experiment at last.Results show that recovery of manganese is92.9％，the percentage of phosphorus andP/Mn ratio reduced to1.58and0.065respectively.Results of high temperature oxidation roasting-acid leaching test show that，thepercentage of manganese increase14.5and19.9respectively at the roasting temperatureis800℃and1000℃. The P/Mn ratio of manganese ore reduce to0.006，and thepercentage of dephosphorization rate and recovery of manganese is increase to91.4and97respectively when roasting temperature is1000℃.Phosphorus removal of leach liquor after leaching of phosphorus-rich manganeseore under electric field enhancement test, result show that the leaching rate ofmanganese under electric field was higher than that direct leaching one, and it is provedthat pyrolusite have no effect on manganese leaching process. Using Ca²⁺, Mg²⁺dissolved in acid leaching process to remove phosphorus as precipitate to obtainmanganese sulfate solution, meanwhile the lime slurry dosage and solution pH werediscussed. Result show that under the conditions of lime slurry solid-to-liquid ratio is1:15, pH3.0the dephosphorization rate reach to98.1％, and loss rate of manganese wasonly4％. This manganese sulfate solution can be used as electrolytic manganesequalified solution after iron removal process.