硫酸盐还原菌的分离纯化及脱硫性能研究

Study on the isolation,purification and desulfurization performance of sulfate-reducing bacteria

硫酸盐还原菌(SRB)是一类能够将含硫氧化物还原成硫化氢的厌氧微生物,其在硫的生物地球化学循环及微生物脱硫过程中极为重要。采用稀释涂布-叠皿夹层法和划线分离法从江汉油田含油污泥及石化废水中分离得到SRB,研究了其生理生化特性及环境因素对菌株脱硫性能的影响。研究结果表明,分离获得的11株SRB菌株均能够有效利用甲醇、乙醇、葡萄糖及柠檬酸三钠、碳酸钠、碳酸氢钠等碳源,可以利用氨氮但不能利用硝酸盐和亚硝酸盐;其中菌株SRB-X2对硫酸盐的还原能力最强,其最佳脱硫温度为30℃,pH范围为6~7;该菌株能有效处理硫酸盐初始质量浓度为1000mg/L的含硫废水且硫酸盐去除率高于65%,当硫酸盐起始质量浓度为200mg/L、SRB-X2菌液体积分数为0.5%~5%时,硫酸盐去除率随着菌液体积分数的增加及处理时间的延长而增加,且菌液体积分数为5%的处理组在72h时对硫酸盐的去除率最高(97.3±3.2%),脱硫效果较好。

Sulfate-reducing bacteria(SRB)are a kind of anaerobic microorganisms that reduce sulfur oxides to hydrogensulfide,and are very important for sulfur geochemical cycle and microbial desulfurization process.The SRB were isolated with dilution coating-plate interlayer method and line separation method from oily sludge and petrochemical wastewater in Jianghan Oilfield,and the effects of physiological and biochemical characteristics and environmental factors on the desulfurization performance of the SRB were studied.Results indicate that all the 11 isolated SRB can effectively utilize carbon sources such as methanol,ethanol,glucose,trisodium citrate,sodium carbonate and sodium bicarbonate;these strains can use ammonia nitrogen while can not utilize nitrate or nitrite.The SRB-X2 has the strongest sulfate reduction ability,and the optimal desulfurization temperature and pH value are 30℃and 6~7,respectively.This strain can effectively treat sulfur-containing wastewater with an initial sulfate mass concentration of 1000 mg/L and the sulfate removal rate is higher than 65%.As the initial sulfate concentration is 200 mg/L and the volume fraction of bacterial solution of SRB-X2 is from 0.5%to 5%,the removal rate of sulfate increases with the increasing of the volume fraction and the extension of the treatment time.Furthermore,the treatment group with the volume fraction of 5%has the highest sulfate removal rate(97.3±3.2%)at 72 h,which means the desulfurization effect is much better.