匀强电场和微生物联合修复石油污染土壤的实验研究

Bioremediation of oil-contaminated soil under uniform electric(UE) field condition in north Shannxi Province,China

对陕北石油污染土壤进行了微生物和外加电场联合修复的实验研究,实验表明,经过54 d的降解,加菌土样在施加电场条件下石油降解率达到91%,比不加电场土样的降解率79%提高12%,并且在降解初期电场促进了菌剂的生物修复作用,到降解后期,促进作用不明显.分析表明,土壤中的直链饱和烃基本被去除.得出适宜的施加电场条件为辐照时间为10 min,电场强度为300 V.m-1,土壤中石油去除率变化与微生物脱氢酶变化趋势基本一致,表明外加电场刺激了微生物脱氢酶的分泌,对石油污染土壤的生物修复具有积极的促进作用.

Bioremediation of oil-contaminated soil under the uniform electric （UE） field condition was experimentally studied. The results showed that, under the UE field condition, the degradation rate of bacteria-inoculated soil was better than that of non-inoculated soil. Meanwhile,a higher degradation rate for the UE field-imposed soil（UEFIS）was obtained than that of the UE field-absent soil（UEFAS）. After 54 days of biodegradation,the removal rate of oil pollutants for UEFIS reached to 91%which was 12 percent higher than that for UEFAS. At the early stage of biodegradation, the UEFIS can accelerate the predominant bacteria biodegrading the oil-contaminated soil,however this effect decreased at the end of the biodegradation. By means of the GC-MS analysis, saturated hydrocarbons（C10-C40 ）contained in the oil-contaminated soil were almost completely degraded. 10min of radiation time and 30 V · m^-1 of electric strength can be considered as the optimum conditions of the UE field to biodegrade the oil-contaminated soil. Under this condition, the variation tendency of oil pollutants removal were in good accordance with that of dehydrogenase secreted by the predominant bacteria,which indicated that imposing of the UE field on the oil-contaminated soil can promote the production of dehydrogenase and the pollutants＇ biodegradation.