微生物对煤矿固体废弃物的脱硫效应

Desulphurization effects of microoganisms on gangue in coal mine areas

煤矸石是煤矿特有的一种固体废弃物,应用本实验室筛选出的氧化亚铁硫杆菌Thiobacillus ferrooxidans和嗜酸氧化硫硫杆菌Thiobacillus thiooxidans对宁夏大武口高硫煤矸石进行微生物脱硫技术及应用条件的研究,如不同煤矸石粒径、不同接种浓度和不同煤矸石浓度。2种脱硫细菌对煤矸石的脱硫效果显著,小粒径煤矸石的微生物脱硫效果更好。考虑脱硫成本及脱硫效率,Thiobacillus ferrooxidans菌最佳的接种浓度为25%,在Thiobacillus thiooxidans菌悬液中,能脱出最大量硫酸根的煤矸石最佳比例是10%。2种菌混合较单菌株脱硫效果更好,以Thiobacillus ferrooxidans∶Thiobacillus thiooxidans=2∶3的比例混合后对煤矸石的脱硫效果最佳,该结果为煤矿废弃物煤矸石的污染防治提供技术依据。

Gangue is one of the solid wastes in coal mine areas. Two kinds of desulphurizating microorganisms Thiobacillus ferrooxidans and Thiobacillus thiooxidans in the lab were studied for their desulphurization characteristics. They all showed good desulphurization effects on gangue from Dawukou District, Ningxia Province. Experiments of gangue biodesulphurization by bacteria were carried out under different conditions, such as different gangue particle sizes, inoculation concentrations and different gangue densities. The smaller size gangue had higher desulfurization rate. Leaching sulphate concentration was increased when inoculation concentrations superinduced, difference between 25% and 50% inoculation was not obvious after several days of bioleaching. Considering the leaching cost and effects, 25% inoculation Thiobacillus ferrooxidan concentration in the bioleaching was more appropriate. Lower gangue density caused higher desulfurization rate per gram of gangue, 10% gangue density was convient. The optimum mixing ratio of Thiobacillus ferrooxidans and Thiobacillus thiooxidans was 2：3 ,its desulphurization effect was better than that of other ratios. These results would give the support for the further gangue pollution provention.