Bio-Physiochemical Beneficiation of Low Grade Coal from Lakhra Mine, (Sindh) Pakistan

Low grade coal of Lakhra mines was beneficiated using bioleaching technology. This technique has more advantages over their counterparts such as chemical and physical techniques due to its easy processing, simplicity, having no environmental pollution, economic feasibility and maximum removal of contamination like sulfur and ash present in coal composition. Presently bacterial strain of Thiobacillus ferrooxidans was isolated and purified from indigenous sources i.e. Coal mine drainage, hot spring water and soil adjacent to sulphide mineral ore, using simple screening, serial dilution and growth culturing. Isolated microorganisms were applied on low grade reduced size/powdered coal collected from mines site. Chemical evolution of coal revealed that this sample has 44.45% of ash and 7.03% of sulfur along with 2.3% of Iron. Microbial processing was continued for maxim 36 days which successfully reduced up to 57.33% of sulfur, 75.21% ash and 87.7% iron. Optimization of parameters such as pH, grain size, aeration time and pulp density were also been optimized. The results were confirmed by 100, 50 and 20 magnification of scanning electron microscope (SEM) fallowed by Fourier transform infrared spectroscopy (FTIR).