Mineralogy and quality of Banti Coal, Baraka District, Enrekang Regency, South Sulawesi Province, Indonesia.

Abstract

Coal deposits in Banti Village, Enrekang Regency, South Sulawesi Province, Indonesia are geographically located at coordinates: 03°27‘59.72” south latitude and 119°51‘34.35” east longitude and are categorized as medium coal quality. This is evidenced by the results of several analysis that have been carried out. Microscopic analysis showed that there were three dominant minerals such as quartz, pyrite and clay. While the results of mineralogical analysis using X-ray diffraction (XRD) coal in Banti Village show the contents of minerals such as quartz, illite, kaolinite, pyrite, and hematite. Proximate and total sulfur analysis of Banti coal was carried out in 3 samples, namely; sample ENRE-1A, ENRE-1C, ENRE-1D. Banti coal samples shows the average value of total moisture 2.29%, 13.79% ash content, 28.77% volatile matter, 55.83% fixed carbon, and 1.16% total sulfur content. ENRE-1A coal sample shows total moisture 3.20%, ash content 13.72%, volatile matter 27.57%, fixed carbon 55.52%, and total sulfur content 1.84%. ENRE-1C coal sample contains the lowest total moisture which is 1.68%, the highest ash content is 16.9%, volatile matter is 27.79%, fixed carbon is 53.76%, and total sulfur content is 0.92%. ENRE-1D coal sample showed total moisture content of 1.98%, ash content of 10.76%, volatile matter of 31.06%, fixed carbon of 65.2%, and total sulfur content of 0.70%. Analysis of calorific value of Banti coal samples respectively shows 6,785 kcal/kg for sample ENRE-1A, 6,794 kcal/kg for sample ENRE-1C, and 7,229 kcal/kg for sample ENRE-1D. Analyses of the three coal samples were carried out based on ASTM 1981. The presence of quartz, illite, kaolinite, pyrite, and hematite minerals in the coal samples affects the hight ash content in Banti coal. The sulfur content present on Banti coal is mainly due to the presence of pyrite. In general, the ash and sulfur content of Banti coal is classified as medium coal category. Banti coal has good quality for further study, especially coal seam ENRE-1D (coal seam containt hight calorific value and low total sulfur content).