石油污染地表土壤的微生物降解特征

Characteristics of the biodegradation of the ground soil contaminated by crude oil

在石油的生产和储运等过程中会造成土壤被石油污染的问题,进而引起生态环境损害.本文利用热蒸发烃分析仪(GHM)对石油污染土壤进行定性定量分析,进行了油污土壤的微生物降解研究.分析结果表明:油井附近的油污土壤中存在着嗜油微生物,它们对落地石油具有较明显的降解作用;抽油生产史长的油井周围土壤中存在自然驯化出的更多嗜油微生物,其近井土壤中污油的降解速度快;随着微生物降解作用的不断进行,样品中污油的相对降解速度逐渐加快,相对降解率逐渐增加,污油样品中气态组分含量随降解时间延长而增加.实验证明,微生物对污油确实存在较强的选择性降解消耗作用,可以减轻石油生产对土壤的破坏及对环境的污染.

The ground soil is contaminated by crude oil, and ecologic environment is further damaged during petroleum production and storage-transportation in oilfields. The contamination is qualitatively and quantitatively analyzed by using Geofina Hydrocarbon Meter (GHM), and the biodegradation of the contaminated soil is studied by experiments. The analysis results show that, there are oilophil microbes in the contaminated soil near wellbore zone, and they have obvious degradation of the crude oil; the longer the pumping history of oil wells, the more the naturally domesticated microbes in the soil near wellbore zone and the quicker the degradation of the crude oil; the degradation speed and the degradation degree of the crude oil increase -with the increase of degradation time; the amount of the gas-state component in the oily soil samples also increases with the increase of degradation time. The experiments show that the microbes have really strong selective degradation effect on the crude oil, which can reduce the damage of petroleum production to the soil and the pollution of it to environment.