石油烃微生物降解的营养平衡及降解机理

利用从辽河油田分离出的石油烃降解菌,采用生物泥浆法,研究了土壤中石油烃污染物生物降解过程中营养物质供给的平衡关系及其影响降解的机理.试验结果表明:本试验条件下土壤中石油烃降解所需营养物质氮磷的配比为5.67∶1,这一比例与细胞中氮磷元素比例接近;对含油1.4%～1.5%的土壤,摇瓶试验处理16d后除油率可达30%以上.考察了(NH₄)₂SO₄、NH₄NO₃、NaNO₃、CO(NH₂)₂分别作为氮源的影响,试验结果表明,4种氮源对石油烃的微生物降解均有明显的促进作用,而且无机氮源比有机氮源更好,硝酸盐形式的氮比铵态氮更有利,营养盐的作用主要是促进了微生物的生长繁殖,同时改变体系pH值,使之有利于降解过程.

Nutrient Balance and Mechanism of Biological Degradation of Oil

This paper studied the nutrient balance and mechanism for enhancing the bioremediation of petroleum contaminated soils by the bio-slurry method. Oil degrading strains isolated and screened from Liaohe oil field was used. The results show that the suitable weight ratio of N and P element in the nutrient is 5.67:1, which is similar to their proportion in the microbial cells. It was found that the degradation of oil was significantly enhanced by adding nutriment and about 30% oil was decreased in the 14,000 mg/kg-15,000 mg/kg samples during 16 days. Using (NH4)2SO4, NH4NO3, NaNO3, CO(NH2)2 as the nitrogen source respectively, it shows that the inorganic nitrogen is better than the organic one, and the nitrogen in nitrate is more effective than that in ammonia. Adding nutrient salt can change the system's pH and promote the growing of the microbes.