Experimental Study on the Beneficiation of Aphanitic Graphite Ore from Lutang in Hunan

To utilize an aphanitic graphite ore from Lutang in Hunan province, the beneficiation research was conducted. The disseminated grain size of the ore is very fine and intimately associated with easy floating minerals such as chlorite. According to the nature of ore, the effect of slurry dispersion and inhibition on flotation was studied. In this study, kerosene was chose as the collector, sodium carbonate was used as the dispersant, a combined reagent (sodium silicate:sodium carboxymethyl cellulose=14:1) was used as the inhibitor, and secondary octanol was used as the frother. Finally, graphite concentrate with carbon content of 86.26% and recovery of 76.45% was collected from a raw ore with 70.28% carbon using a closed circuit with three stages of grinding, one stage of roughing and five stages of cleaning. The results of microscope and SEM observations of the final concentrate demonstrated that the difficulty in further improvement of grade could attribute to the existence of fine-grained gangue and ultra-fine grained graphite-quartz. Therefore, chemical purification process is recommended for further treatment.