Biodesulfurization from the High Sulfur Coal with a Newly Isolated Native Bacterium, Aspergillus sp. DP06

摘要

In this paper, we made attempt to desulfurize the coal collected from Yibai coalfield of Qingbai province in China contains high total sulfur content (4.97% by mass) and high organic sulfur content (3.37% by mass). The high sulfur coal sample was subjected to desulfurization by using a new bacterium isolated from the native coal mine site. The molecular identification of the 18S rRNA gene showed that the native bacterium was Aspergillus sp., denoted as DP06, and it is reported first time for the capability to remove about 47% of total sulfur from the coal. To improve biodesulfurization performance, the effect of various parameters such as medium pH, pulp density, incubation time, and incubation temperature on the desulfurization was investigated and the optimal values were found as pH 5.0, 5% of pulp density, 8 days, and 35°C, respectively. Final total sulfur content of the desul-furized coal with DP06 was reduced to 2.63% (organic sulfur 1.45% + pyritic sulfur 0.53% and 0.65% of sulfate sulfur). Collaborative treatment high sulfur coal sample by using native bacterium DP06 and Tbiobacillus ferrooxidans was studied and demonstrated 59% of total sulfur removed from the coal sample. Results of analytical characterization have indicated that the treatment of high sulfur coal with native bacterium DP06 has caused the increase in calorific value from 6329 cal/g to 6521 cal/g, but the ash content of coal was eliminated.