Desulfurization and deashing of Hazro coal via a flotation method

In this study, desulfurization and deashing of Hazro coal via a flotation method were studied. For this purpose, experimental studies were conducted on the coal sample with ash, sulfur, volatile matter, and fixed carbon contents of 24.77%, 6.90%, 35.18%, and 38.06%, respectively, and two groups of flotation experiments were made. The effects of pH, collector amount, and various frothers (MIBC, AF 76, pine oil, DF 250) on the depressing and floating pyrite from Hazro coal were investigated in the first and second group flotation experiments, respectively. Flotation results indicated that, when compared to various frothers, the following order for the depressing of pyrite was obtained: MIBC > pine oil > AF 76 > DF 250. For the floating of pyrite, the following order was obtained: DF 250 > pine oil > AF 76 > MIBC. A concentrate containing 1.12% pyritic sulfur and 13.02% ash with a pyritic sulfur reduction of 66.86% was obtained from a feed that contained 4.95% pyritic sulfur and 24.77% ash. The flotation method removed most of the sulfate sulfur (> 90%) and 66.86% of the pyritic sulfur from the coal sample.