石油污染土壤生物修复的强化技术

Study on Enhanced Technology of Oil-contaminated Soil Bioremediation

为探索石油污染土壤的高效修复方法,从实验室保存的优势菌中筛选得到4株降油效果最佳菌,采用摇床和恒温培养箱培养,对含油量为5%的石油污染土壤进行微生物菌剂强化处理和环境强化实验。微生物菌剂强化结果表明:4种菌和除油效果最好的A、C、D混合菌3d可将石油烃依次降解24%、19.81%、22.55%、26.46%、39.67%;并对该菌群的最佳投加配比进行确定,A、C、D菌群数量的最佳配比为NA∶NC∶ND=1∶2∶0.5,3d内菌群A、C、D在最佳接种配比情况下可将石油烃降解44.2%。环境强化实验结果表明:A、C、D菌群在最佳修复条件营养物质C∶N∶P为75∶8∶3、表面活性剂为0.5%、通气条件为6层纱布、电子受体H2O2的加入量为1.5%下,3d内石油烃降解61.46%,比自然条件下修复的除油率4.7%提高了56.76%,较只进行菌种强化时最高除油率44.2%提高了约17%。

In order to explore better treatment process of oil contaminated soil, four optimized bacteria that can degrade petroleum efficiently are selected from the predominant bacteria which are stored by our laboratory. Their environmental strengthening test and microbial agent strengthening processing were conducted using shaking cultivation and incubator in the oil-contaminated soil containing 5% oil. The results of microbial agent strengthening indicate that the reduction of petroleum hydrocarbons of four strains and a mixed strain are 24%, 19.81%, 22.55%, 26.46% and 39.67% respectively. A test performed to determine the best ratio of the flora ACD shows that the best number ratio of the flora A, C and D is NA ： NC ： ND=1 ： 2 ： 0. 5 within 3 d, and the flora A, C and D in the best circumstances can degrade 44.2% oil. The results of environmental strengthening test indicate that the flora A, C and D in the best conditions for the ratio of nutrients C ： N ： P is 75 ： 8 ： 3, and the content of surfactant is 0.5 %. In the ventilation conditions for the six gauze and E-receptor H2O2 is 1.5%, the degradation of petroleum hydrocarbons is 61. 46% within 3 d, and the degradation rate increase 56. 76% compared with that under natural conditions which is only 4.7%, and increase 17% compared with the degradation rate of 44.2% when only strengthening the bacteria.