RESEARCH ON REDUCTION-MAGNETIC SEPARATION OF BAYAN OBO ORE

摘要

Bayan Obo ore in Inner Mongolia is a uncommon and huge multi-metal symbiotic deposit involvingrniron, rare earth, niobium, thorium etc. As many as 26 elements can be utilised comprehensively.rnHowever, due to its low grade, complicated mineralogical characteristics, fine and inhomogeneousrndissemination and containing many available valuable components, a lot of difficulties can berncaused in traditional dressing and smelting process. Besides, low level of comprehensive utilisationrnof resources and serious environmental pollution are big problems. In this paper, the deoxidisedrnore with high metallisation rate was obtained by deep-deoxidisation process. By this technics, iron,rnrare earths and niobium were separated effectively and concentrated by magnetic separation afterrngrinding. The deoxidised ore with a metallisation rate of 94.48 per cent was obtained by optimisingrnoperation parameters in experiments such as reducing temperature and time, carbon additives,rnetc. And then, iron powder with Tfe 91.61 per cent, metallisation rate 93.79 per cent, Fe recoveryrn93.23 per cent was obtained by stage-grinding and treating coarse and fine particles separately. Therniron powder can be used as the raw material of steel making, and the residue with RE2O3 gradern12.25 per cent, recovery 98.73 per cent can be further processed to obtain rare earth and thoriumrnconcentrates.