Abstract:

Based on the bioremediation requirements of heavy-petroleum-contaminated sites, this study successfully constructed a highly efficient mixed bacteria group of heavy petroleum degradation and evaluated the degradation performance of mixed consortium by changes in the composition structure and functional groups of heavy oil before and after degradation. The results showed that the microbial community structure was significantly different at different stages of heavy oil degradation. Pseudomonas, Reyranella, Parvibaculum and Pseudoxanthomonas played a major role in the degradation of heavy oils, of which Parvibaculum and Pseudoxanthomonas played a major role in the degradation of heavy components. After long-term continuous intensive culture of heavy petroleum degradation mixed consortium, the degradation rate of heavy oil in 50 days could be increased from 25.42% to 41.57%.The heavy oil degradation rate of mixed culture QM composed by four kinds of mixed consortium enriched from different sources within 20 days and 50 days could reach 42.31% and 53.48%, respectively, and the degradation rate of asphaltene in 50 days could reach 25.56%.After microbial degradation,the content of light components and light groups such as methyl and methylene in heavy oil decreased significantly, while the saturation of heavy components increased, the polycyclic structure was activated, and oxygen-containing heavy components such as esters and ethers were reduced. Efficient and stable biodegradation of heavy oil has been achieved.

Key words: heavy oil, mixed consortium construction, biodegradation, performance evaluation

摘要：

基于重油污染场地生物修复需求，本研究成功构建了高效重油降解混合菌群并通过降解前后重油组分结构及官能团的变化对混合菌群的降解性能进行评价。结果表明，混合菌群的结构在重油降解的不同阶段有明显差异。Pseudomonas、Reyranella、Parvibaculum和Pseudoxanthomonas等菌属在重油降解过程中先后起到主要作用，其中Parvibaculum和Pseudoxanthomonas属的功能菌在重油重质组分的降解中或起主要作用。经过对重油降解混菌长期连续强化培养， 可使50天内重油降解率由25.42%提升至41.57%。将不同来源富集获得的四种重油降解混合菌群复配得到了QM混合菌群，20天和50天内重油降解率可分别达到42.31%和53.48%，同时50天沥青质降解率可达25.56%。经过菌群降解后重油内轻质组分及甲基、亚甲基等轻质基团含量大幅度下降，同时重质组分的饱和度增大、多环结构被活化、酯、醚等含氧重质组分实现轻量化,实现了高效且稳定的重油生物降解。

关键词: 重质石油, 混合菌群构建, 生物降解, 降解性能评价