Effects Of Several Kinds Of Bacteria On The Coal Desulfurization

The effects of several kinds of bacterium, especially silicate bacteria, on the coal desulfurization were studied in this paper.The silicate bacteria grew well in the condition that coal acted as nutrition substrate. So the silicate bacteria which grew in the culture medium of sulfur coal removaled sulfur of coal. The result indicated that:Firstly, there was some desulfurization effect after treatment of the silicate bacteria, and the maximum removal ratio was 35.78% for total sulfur. After treatment, the sulfur content of coal sample was only 3.50%. Secondly, compared with the means of static cultivation for the silicate bacteria, the way of shaking table cultivation was better for coal desulfurization effect.Using the strain S03 and S06 of Acinetobacter which came from groundwater started to the desulfurization experiment. The results indicated that the strain S06 had better desulfurization than the strain S03. The maximum removal ratio was 31.38% for total sulfur. After treatment, the sulfur content of coal sample was only 3.74%. This made known that the strain S03 and S06 had a definite desulfurization, but the effect was not ideal.Adopting the strain NJDX1-â‘£started the experiment of desulfurization. The result indicated that the strain had some effect for coal desulfurization. Especially, it had much better effect for inorganic sulfur of coal. Through changing the sulfur content of culture medium, the desulfurization ability of the strain NJDX1-â‘£could be increased. So it was agreed that the strain NJDX1-â‘£could have oxidation and desulfurization for the sulfur of pyrite.Through the single factorial experimrnts and the orthogonal experimrnt about the conditions of coal desulfurization affected by the silicate bacteria, the results were shown that the silicate bacteria should grow in the liquid culture medium of nitrogen for coal desulfurization experiment. The best conditions of dealing with coal sample were that access time was 6d, the rotation rate of shaking table was 170r/min, the dosage of the coal sample was 6g, and the dosage of the silicate bacteria was 50mL. In the above conditions, the maximum desulfurization ratio was 36.87%.Using the silicate bacteria which growed in the different culture mediums with nitrogen or no nitrogen, it started the experiment of coal desulfurization. The mechanism made clear that the silicate bacteria had the oxidation for the sulfur of iron sulphides in coal, and it also had the absorption and transformation for organic sulfur with inorganic sulfur. The silicate bacteria dealed with the pyrite and ferrous sulphide of low valence state, which growed in the culture medium of nitrogen. The result indicated that the silicate bacteria with its metabolite had oxidation for the inorganic sulfur of low valence state. The further study of the coal desulfurization indicated that the silicate bacteria with its metabolite had oxidation for the sulfur of coal, and the silicate bacteria had absorption and transformation for the the sulfur of coal.The microbe technology is used for the coal desulfurization. The bacteria could specially remove inorganic sulfur, which has complex structure and extra fine disseminated grain size, and also remove parts of organic sulfur. It is a new technology of coal desulfurization for being good with environment, with the merits for the facile reaction condition, few invest, low cost and little environmental pollution, and has wide application foreground. This work has important referrence value for carrying on the engineering study of biological desulphurization about coal.