石油污染土壤的微生物生态原位修复研究

目的]研究微生物生态技术对中原油田石油污染土壤的修复效果。方法]在前期室内外模拟修复试验的基础上,选择中原油田某油井场旁石油污染场地,设置5种修复条件,开展微生物生态技术修复石油污染土壤研究。结果]经过99d修复后,黑麦草（苜蓿）微生物联合技术、纯微生物技术和黑麦草（苜蓿）技术对石油污染土壤具有明显的修复作用,其中的石油烃降解率均在40.00%以上,以黑麦草微生物联合技术修复效果最佳,石油烃降解率达67.38%;修复过程中易溶盐、NO3-、Cl-等易溶营养物质只有极小部分随水而进入下部土层（50cm）;由于苜蓿草的根部可能具有固氮作用,使加入的大量化肥进入了土层下部,导致3和5号修复区50cm土壤层NH4＋明显增大。影响修复效果的因素包括温度、水、氧气、营养元素、微地质环境等。结论]原位微生物生态修复技术在野外原位石油污染土壤修复效果是显著的,具有处理方法简单、费用低、修复效果好、对环境影响小、无二次污染、可原位治理等优点。

Research on the Microbial Ecological Remediation in Situ of the Soil Contaminated by Petroleum

Objective] The remediation effect of petroleum-contaminated soil in Zhongyuan Oilfield region with microbial ecology technology was studied.Method] Based on the indoor and outdoor simulation experiment in the remediation of petroleum-contaminated soil,the contaminated site in the oil well of one oilfield being selected as experimental place and five kinds of remediation conditions being used repair in experimental design,the study on the microbial ecological remediation of the petroleum-contaminated soil was conducted.Results] The significant remediation effect on petroleum-contaminated soil appeared in the microbial treatment jointed with ryegrass(alfalfa)growing,pure microorganism technique and ryegrass growing(alfalfa)after 99 days' experiment.The degradation rate of petroleum hydrocarbon was over 40.00% and the highest degradation rate of petroleum hydrocarbon was 67.38%,which was from the microbial treatment jointed with ryegrass(alfalfa)growing.During the repairing process,few proportion of soluble salt,NO3-,Cl-and other soluble nutrients were leaked into the lower soil layer(50 cm)with water.Because of the roots of alfalfa had the function of nitrogen-fixed and a large number of fertilizer were applied into the lower part of soil,the content of NH4+ in the soil layer(50 cm)of the experimental site No.3 and No.5 was significantly increased.The factor affecting the remediation was the temperature,water,oxygen,nutrient,micro-geological environment and others.Conclusion] The technology of microbial ecological remediation in situ applied in the restoration of petroleum-contaminated soil showed the significant effect,with the simple treating method,low cost,good effect,little effect on environment,without secondary pollution,in situ treatment and other advantages.