biodesulfurization of tabas coal in pilot plant scale

sulfur emission from coal combustion presents many environmental problems. the techniques used to reduce the amount of sulfur in coal before combustion, include physical, chemical and biological processes.biological processes based on degradation of sulfur compounds by microorganisms offer many advantages over the conventional physical and chemical processes. the processes are performed under mild conditions with no harmful reaction products and the value of coal is not affected. in this article the progress achieved to date in biodesulfurization of tabas coal in pilot plant is reviewed. effect of particle size and pulp density at constant temperature on coal biodesulfurization investigated in this research. the best results obtained was 45% of pyritic sulfur and 20% of total sulfur in reduction at pulp density of 10% and 0-0.5 mm particle size within  14 days.