石油降解菌群富集及其在石油污染土壤修复中的应用研究

发布时间：2018-01-18 07:08

本文关键词：石油降解菌群富集及其在石油污染土壤修复中的应用研究　出处：《浙江大学》2015年硕士论文　论文类型：学位论文

【摘要】：石油在工业中应用非常广泛,是现代社会最主要的能源之一,由于石油一种成分非常复杂的混合物,难以被降解,所以泄漏的原油进入土壤和水体环境后会造成严重的、持续性的污染。现有石油污染处理主要方法包括物理、化学和生物方法,其中生物方法因其高效、经济和处理彻底的优点被广泛重视。而生物方法中的关键问题是高效石油烃降解菌群的富集、菌群与物理化学方法结合以达到较高的修复效率。本研究从采自山东胜利油田的石油污染土壤中富集出一个高效石油烃降解菌群PWW,以无机盐为培养基时对脱水原油的降解率达5.7 mg/L-d。该菌群最适pH值为7.0,尿素、硫酸铵、氯化铵或硝酸钾作氮源对该菌群降解石油无明显影响,酵母膏、蛋白胨等易吸收有机碳源对该菌群降解石油有明显的促进作用。表面活性剂聚氧乙烯脱水山梨醇单油酸酯(Tw-80)、十二烷基苯磺酸钠(LAS)及十二烷基硫酸钠(SDS)可显著提高该菌群的石油降解效率,1000.0 mg/L LAS、26.3 mg/L Tw-80+173.7 mg/L SDS、22.3 mg/L Tw-80+177.7 mg/L LAS,可使PWW菌群在17天内对石油的降解率达到93%、93%、88%,显著高于对照组20.0～26.3 mg/L Tw-80和2500.0 mg/L SDS。微生物群落结果研究表明,该菌群主要功能菌为金黄杆菌属(Chryseobacterium)等。PWW菌群对石油污染土壤有良好的修复效果。石油污染程度3%的土壤在150天内石油被降解率达59%。26.3 mg/L Tw-80+173.7 mg/L SDS、22.3 mg/L Tw-80+177.7 mg/LLAS的混合表面活性剂与PWW菌群联合修复石油污染程度32%的土壤120天石油降解率高达46%,而添加5.0 g/L的表面活性剂显著抑制土壤中菌群活性。用吸附法和包埋法将该菌群制成菌剂后的实验证明,选用1：1混合的麸皮和草炭制作的吸附法菌剂对石油降解率1.30 g/kg-d;选用海藻酸钠(SA)与聚乙烯醇(PVA)按1：10配比制作的包埋法菌剂对原油降解率可达1.89 g/kg-d。
[Abstract]:Petroleum is widely used in industry and is one of the most important energy sources in modern society. It is difficult to be degraded because of a very complex mixture of petroleum components. Therefore, the leakage of crude oil into the soil and water environment will cause serious and persistent pollution. The main methods of oil pollution treatment include physical, chemical and biological methods, among which biological methods are highly efficient. The advantages of economy and thorough treatment have been paid more attention to. However, the key problem in biological methods is the enrichment of high efficiency petroleum hydrocarbon degrading bacteria. In order to achieve higher remediation efficiency, a highly efficient petroleum hydrocarbon degrading bacteria (PWW) was obtained from petroleum contaminated soil collected from Shengli Oilfield in Shandong Province. The degradation rate of dehydrated crude oil reached 5.7 mg / L ~ (-1) d when inorganic salt was used as the medium. The optimum pH value of the bacteria was 7.0, urea, ammonium sulfate. Ammonium chloride or potassium nitrate as nitrogen source had no obvious effect on the degradation of petroleum by the bacteria, yeast extract. The easily absorbed organic carbon sources such as peptone can promote the biodegradation of petroleum. The surfactant polyoxyethylene dehydrated sorbitol monooleate Tw-80). Sodium 12 alkylbenzene sulfonate (LAS) and 12 alkyl sodium sulfate (SDSs) could significantly improve the petroleum degradation efficiency of this bacterium by 1000.0 mg/L LAS. 26.3 mg/L Tw-80 173.7 mg/L SDS,22.3 mg/L Tw-80 177.7 mg/L LAS. The results showed that the degradation rate of PWW bacteria to petroleum reached 933% in 17 days. It was significantly higher than that of the control group (20.0 ~ 26.3 mg/L Tw-80 and 2500.0 mg/L SDS.). The main functional bacteria of this flora are Chryseobacterium (Chryseobacterium). PWW microflora has good remediation effect on petroleum-contaminated soil. The degradation rate of petroleum in 3% soil reaches 59.26.3 mg/L Tw-80 within 150 days. 173.7 mg/L SDS. 22.3 mg/L Tw-80 177.7. Mg/LLAS mixed surfactants combined with PWW microflora to remediate the soil with 32% degree of oil contamination, the oil degradation rate of 32% days was up to 46% days. The addition of 5.0 g / L surfactant significantly inhibited the microbial activity in soil. 1: 1 mixture of wheat bran and peat was used as adsorbent to degrade petroleum 1.30 g / kg-d. Sodium alginate (SA) and polyvinyl alcohol (PVA) were used as entrapment agents at 1:10. The degradation rate of crude oil was 1.89 g / kg 路d.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X53;X172

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