Abstract: Biological processes based on oxidation of sulfur
compounds by chemolithotrophic microorganisms are emerging as an
efficient and eco-friendly technique for removal of sulfur from the
coal. In the present article, study was carried out to investigate the
potential of biodesulfurization process in removing the sulfur from
lignite coal sample collected from a Mongolian coal mine. The batch
biodesulfurization experiments were conducted in 2.5 L borosilicate
baffle type reactors at 35 ºC using Acidithiobacillus ferrooxidans.
The effect of pulp density on efficiency of biodesulfurization was
investigated at different solids concentration (1-10%) of coal. The
results of the present study suggested that the rate of desulfurization
was retarded at higher coal pulp density. The optimum pulp density
found 5% at which about 48% of the total sulfur was removed from
the coal.
Abstract: The desulfurization of coal using biological methods is an emerging technology. The biodesulfurization process uses the catalytic activity of chemolithotrophic acidpohiles in removing sulfur and pyrite from the coal. The present study was undertaken to examine the potential of Acidithiobacillus ferrooxidans in removing the pyritic sulfur and iron from high iron and sulfur containing US coal. The experiment was undertaken in 10 L batch stirred tank reactor having 10% pulp density of coal. The reactor was operated under mesophilic conditions and aerobic conditions were maintained by sparging the air into the reactor. After 35 days of experiment, about 64% of pyrite and 21% of pyritic sulfur was removed from the coal. The findings of the present study indicate that the biodesulfurization process does have potential in treating the high pyrite and sulfur containing coal. A good mass balance was also obtained with net loss of about 5% showing its feasibility for large scale application.