The Research On Application Technique For Rare Earth Leaching Residue As Resources

In this paper, the distribution status of rare earth resources in the world was analyzed, the innovation and the development of research field and exploiting technique, and the production and the ulilization prospects for rare earth were introduced. Based on the existing problems in exploiting and the utilization of rare earth in Sichuan, the technical programmes and the research objectives for resolving rare earth leaching residues were proposed.Firstly, in the experimental research, the chemical compositions and the mineral associations in the leaching residues were examined, the disseminated characteristic of main mineral in the leaching residues was researched;then through the comparison test on the multi-technique programme, the research adopted the technical progromme of magnetic separation-flotation but rare earth leaching residues no grinding for optimal experimental research on the technological condition of the magnetic separation and the flotation, the rational flotation reagent types and reagent regimes were selected, and the comprehensive beneficiation conditions of optimal magnetic separation-flotation were determined. The obtained rare earth concentrate contained RED of 48.97% with REO recovery of 91.59%. Finally, according to the physico-chemicalproperties of barite, it was recoveried from the tailings obtained after concentrating rare earth mineral by gravity concentration, the barite concentrate grade(BaS04) is 92.50% with the recovery of 74. 03%.The research on the magnetic concentration indicated that the better beneficiation for rare earth mineral separating from the gangue minerals is due to the sufficient magnetic field force was produced by the magnetic concentrator through adopting magnetic plate medium and adjusting exciting current. The research on the electrodynamic potential and the solution chemistry indicated that during H205 reacted with rare earth mineral, the hydroxamate anions were not adsorbed on rare earth mineral surface by the electrostatic attraction force, but entered into the closed layer in double electrode layer of rare earth mineral, then adsorbed the hydrolyzed cations in the mineral surface by chemical adsorption and formed several hydroxyl complexes;finally adsorbed on the surface of rare earth mineral. The research on the mechanism of sodium silicate action indicated that in the range of pH 7.5-8.5, optimal flotation separation of rare earth mineral from barite etc. can be attained.The technique which rare earth leaching residues were used as resources introduced in this research has proposed an effective utilization way for rare earth leaching residues for rare earth production enterprises.