Research On Flotation And Magnetic Separation Technology For The Low-grade Manganese Carbonate Ore In West Hunan Province

Manganese ore is raw material of electrolytic manganese and the high-grade manganese oreis being exhausted in China. It is the main subject of using the mineral processing to improve thegrade of the refractory manganese ore which grade is low, dissemination size is fine andconstituents is complicated for decreasing the energy consumption of electrolytic manganese.The thesis makes the flotation and magnetic separation experiment research on thelow-grade manganese ore of the West Hunan Province. It is found that the mainmanganese-bearing mineral of this manganese ore is rhodochrosite which manganese grade is10.96%and the main gangue mineral is clay minerals. They are all cryptocrystalline texture andclosely coexistence. The of these minerals is less than10μm.This research makes the flotation and magnetic separation experiment study on thelow-grade manganese ore of the West Hunan Province. It also makes the study and analysis onthe separating effect and mechanism of these two separation methods.The results of flotation experiment shows that the grade of concentrate can be improve to17.47%and the recovery rate of scavenging tailing can be decreased to36.95%by two stagecleaning and scavenging which used sodium oleate as collector and sodium silicate, sodiumhexametaphosphate as inhibitor.The roughing manganese concentrate can be obtained which grade is22.91%and recoveryrate is48.05%by high-intensity magnetic separation when the magnetizing intensity field is1.27×10~6A/m and then the separation index of the manganese concentrate also can be improvedto that the grade is20.70%and the recovery rate is70.66%by four-stage scavenging. The thesisuses weakly magnetic of rhodochrosite to improve the hydrophobic flocculation of themanganese carbonate ore by external magnetic field, and the manganese concentrate can beobtained which grade is22.43%and recovery rate is67.86%by high-intensity magneticseparation when the magnetizing intensity field is1.27×10~6A/m, the external magnetic field ofhydrophobic flocculation is0.64×10~6A/m and the stirring speed of hydrophobic flocculation is1000r/min. The recovery rate is improved by19.87%when the grade changes little whatsignificantly improves the separating effect of the low-grade manganese ore of the West HunanProvince.Then the roughing manganese concentrate can be obtained which grade is21.18%andrecovery rate is75.48%by high gradient magnetic separation when the magnetizing intensityfield is0.80×10~6A/m.