Process Mineralogy of Uranium Ore with High Fluorine

Abstract

Process mineralogy of a uranium ore which had U (0.22%) and F (1.04%) was investigated by modern SEM-based mineral liberation analysis (MLA) system and traditional process mineralogy research methods. The results indicate that traces of uranium minerals are mainly pitchblende, small amount of coffinite and brannerite in this ore. Pitchblende, coffinite and brannerite are fine and mainly embedded in quartz, muscovite and calcite. The content of pyrite and fluorite are 0.436% and 2.177% respectively. Fluorine minerals are mainly fluorite which is harmful to bioleaching. The content of quartz is 64.9%, which is the main gangue in this ore. The characteristic of this ore is low content and fine particle size of pitchblende, low sulfide and high fluorine. Bioleaching won't have obvious advantages compare with conventional acid-leaching. The contents of U, Th, Fe, S, P, F, Ca, Mg, Al, Si are 0.22%, 0.059%, 1.09%, 0.53%, 0.012%, 1.04%, 3.26%, 0.36%, 3.90% and 35.69%, respectively. Through crushing, grinding, screening and classification, samples are turned into six size fraction, which are +0.150mm, -0.150+0.074mm, -0.074+0.045mm, -0.045+0.038mm, -0.038+0.025mm and -0.025mm. Screened samples are embedded in resin to make 30mm diameter samples for microscope and MLA test. SEM-based mineral liberation analysis (MLA) system, instead of traditional methods, is now widely used in the process mineralogy worldwide (1,2). The system has been maturely used in the process mineralogy study of copper, lead, zinc, molybdenum, tungsten, gold, silver, platinum, palladium, vanadium, titanium ores (3-9).