本文旨在研究环境条件下微生物对石油污染土壤的修复情况。从矿井周边土样定向筛选出两株绿脓杆菌,摇瓶降解实验发现,两菌混合培养10 d原油降解率达到95.67%,比单菌培养提高至少32%,即两菌对原油降解具有协同作用。根据降解实验结果制备了混合修复菌剂,并且人工构建石油污染场地,展开中试场地修复试验,模拟不同的操作条件下土壤中原油的降解情况。经60 d修复发现,添加了菌剂的场地,石油烃含量下降趋势明显,每克土壤中石油烃含量从初始的0.8%降至0.1%–0.3%,其中额外添加有机肥作为补充碳氮源的场地,总石油烃降解率最高,达到85.28%。而未添加菌剂的对照组石油烃含量仅减少25.85%。
We studied the remediation of petroleum-contaminated soils. Two Pseudomonas aeruginosa strains were screened from soil samples in the mine environment. The degradation rate of crude oil was 95.67% after 10 days by mixed culture of the two strains, which was 32% higher than that of single bacterium. It means that the two bacteria had synergistic effect on degrading crude oil. Based on the result, bacterial agent was prepared, and the oil pollution sites were artificially constructed to simulate the degradation of crude oil under different operating conditions. During the experiment, the petroleum hydrocarbon content of the sites after treating with the bacterial agent, decreased obviously in 60 days. The content decreased to among 0.1% and 0.3% from the initial 0.8% per gram of soil. Then, the site with organic manure as supplemental source of carbon and nitrogen had the highest degradation rate of 85.28%, compared to that without adding bacterial agent of only 25.85%.