【作者】 廖有贵；

【导师】 田学达；

【作者基本信息】 湘潭大学 ， 化学工程， 2007， 硕士

【摘要】 随着现代生物技术的发展,微生物在环境保护方面的应用前景越来越广阔。本文就微生物在石油污染土壤的石油降解领域进行了菌种的选育、菌株的鉴定、S92菌株微生物学特性、石油降解微生物的紫外诱变、营养平衡与降解机理、以及高效降解菌群在土壤修复中的应用进行了初步研究。本文通过一系列试验,从多种样品中广泛筛选石油降解菌,共筛选得石油降解效果较好的石油降解菌13株,分别为S43、S67、S85、S92、S104、S109、S120、S129、S136、S138、S145、S155、S167。S进一步鉴定,确认为假单胞菌属。其中石油降解效果最好的S92对模拟石油降解的降解率为87.0%。以S92菌株为原菌株通过紫外诱变得到一株石油降解能力提高显著的菌株S-3-15。用此菌株对石油污染土样进行石油降解试验,固液质量比为40%,接种量20%,温度37℃,摇床转速150 r/min,好氧培养15 d,降解率为96.1%。因此,菌株S-3-15将作为以后的石油降解研究试验的菌源。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。对样品按1:45接种,加入氮,磷营养物,在37℃下恒温振荡培养。试验研究结果表明:氮、磷源同时添加效果是最好的,氮、磷元素合适的浓度分别为80 mg/L、20 mg/L.按质量计算的N、P元素的添加比例N:P为4:1。利用菌群生物强化技术能有效提高土壤修复效率,与自然条件下的土壤修复相比,15 d内利用生物强化的降解率达到了94.2%,比自然条件下的降解率提高了38.75%。影响上壤生物修复的因素有温度、氮磷浓度、通氧量等,通过实验得出:随着温度的升高,土壤修复效率增加,生物生长活跃,而低温条件下生物生长缓慢,即使增加通氧量也不能提高降解效果;投加氮磷营养物质能促进微生物生长,提高土壤修复效率。石油降解微生物石油降解运行成本低,不产生二次污染,工艺简单,既有经济效益和环境效益,又具有重要的现实意义。更多还原

【Abstract】 With the development of modern biotechnology,more and more microorganism is used in environmental protection.The screening and determinant of microbial for oil degradation,the characteristic of strain S92,the biotransformation conditions of oil degradation,and the mechanism of Strain S92 and the soil bioremediation by microorganism were investigated.Several sorts of strains were isolated from samples by a series of experiments, 13 of them proved to be satisfactory effect on oil degradation were obtained.The best strain,named as S92 in this paper,with a higher oil degradation efficiency,was identified Pseudomons.S92 was mutagenized to S-3-15 by ultraviolet radiation.The optimum conditions for oil degradation was as follows:ratio of solid to liquid 2:5,inoculation capacity 20%,temperature 37℃,shaking table rotating speed 150 r/min,and aerobic cultivation for 15 d.Under these conditions,an oil degradation rate of 96.1%was gained by using S-3-15.The nutrient balance and mechanism were studied for enhancing the bioremediation of petroleum contaminated soils.The results show that the suitable condition was inoculation to sample at 1:45,And at a rotating speed of 150rpm,30℃of temperature,and 15d for cultivation,the weight ratio of N and P element in the nutrient is 4:1.The effects of different conditions on the bioremediation were studied.The results show that.During the process of 15-day bioremediation,bioaugmentation improved the degradation rate by 94.2%compared with that in nature condition. Microorganism will be more active with the increase of temperature,so does the degradation rate;adding nutrition and oxygen content will also be contributed to microorganism growth and in the end enhance the biodegradation.Therefore,with the advantage of low energy waste,higher efficiency, non-poisonous,harmless and non-secondary pollution,the microorganism oil degradation for polluted soil by oil is worth regarding and a further research.更多还原