石油烃类污染土壤的微生物修复技术

Microbial Remediation of Petroleum Contaminated Soil

以被石油污染的土壤为样品,经过驯化、富集培养,从中筛选出2株高效石油烃降解菌。对这2株菌从形态特征、生理生化指标、分子生物学3方面进行鉴定,确认2株菌分别为褶皱裸胞壳(Emericella rugulosa)和枯草芽孢杆菌(Bacillus subtilis)。通过对膨松剂、表面活性剂、金属离子、氮源、磷源等影响混合菌株石油烃降解能力主要因素的研究,以及正交试验优化,确定了各因素的施用种类以及使用量。结果表明:污染土壤中加入占污染土壤质量1.2%的3%的H2O2,营养物n(C)∶n(N)∶n(P)=100∶6∶1,加入体积分数为1%混合菌液,1.25%膨松剂(樟子松松针),在该条件下降解效果最佳。而添加0.05%的SDS与PE-23的混合物,0.02%的Zn2+,避免重金属元素Hg2+,Pb2+的混入,可进一步提高石油降解率。

Two strains with high oil degradation ability were screened through domestication and enrichment using the oil contaminated soil as a sample. The strains were identified as Emericella rugulosa and Bacillus subtilis in terms of their morphological characteristics, physiological and biochemical properties, and molecular biology. The optimal dosages of leavening agent, surfactant, metal ions, nitrogen and phosphorus source, which are the main factors influencing the oil degradation ability of mixed strains, were determined by orthogonal design. The best degrading effects were obtained when nutrients C： N： P at a mol ratio of 100： 6： 1, volume ratio of mixed solution 1 percent, and leavening agent （ Pinus sylvestris var. mongolica needles） 1. 25 percent, and 3 percent of H2O2 at a level of 1.2 percent of soil mass were all added into the petroleum-contaminated soil. Moreover, the degrading rate could increase when a mixed solution of 0.05 percent of Sodium dodecyl sulfate（SDS） and PE-23 together with 0.02 percent of Zn2. were added into the petroleum-contaminated soil, preventing Hg^2＋ and Pb^2＋ from interfusing, into the contaminated soil.