Reduction of sulfur and ash content on Mallawa’s coal using flotation column method

Abstract

Utilizing coal with high sulfur content can form pollutants of SOx such SO2, which can cause corrosive acid rain. This study aims to reduce the sulfur and ash content of Mallawa’s coal so it can be utilized as industrial fuel. The study use column flotation as the method to reduce the sulfur and ash content of coal. Reagents used are pine oil as frother and diesel oil as collector. Each sample will be flotated during 10, 15, 20, and 30 minutes with varying grain sizes 40, 65, 80, and 100 mesh. Proximate analysis shows Mallawa’s coal has 12.52% moisture content, 14.67% ash content, 41.67% volatile matter and 31.24% fixed carbon. The result of sulfur analysis shows Mallawa’s coal has 2.74% total sulfur content. The caloric value of the coal sample is 5,698.29 cal/g. Quality characteristics of Mallawa’s coal based on the study are classified as sub-bituminous B coal. Mineral matter identified in coal samples from the microscopy and XRD analysis are quartz, pyrite, kaolinite, and hematite. Flotation performance shows the decreasing of sulfur content range from 16.33 to 55.88%, with the highest percentage at flotation time is 20 minutes and grain size 80 and 100 mesh. Decreasing of ash content range from 6.32 to 38.59% with the highest percentage of flotation time is 20 minutes and grain size 80 and 100.