油藏环境异化铁还原菌的生物多样性

The Biological Diversity of Dissimilated Iron Reducing Bacteria in Oil Reservoirs

为了给低渗透油藏和水敏性油藏高效开发提供新思路,从青海油田(低渗透)、胜利油田(低渗透)和中海油天津(水敏)采集样品;以无定形氢氧化铁作为固相电子受体、混合碳源作为电子供体,富集培养异化铁还原菌(DIRB);并通过高通量测序表征生物多样性。结果发现富集样品α多样性显著减少;β多样性揭示原始样品和富集样品在群落结构上相关性强。微生物组成和系统发育分析表明,青海油田中的DIRB主要有梭菌、脱硫弧菌、希万氏菌、假单胞菌和热孢菌;胜利油田为梭菌、嗜热厌杆菌、热孢菌、脱铁杆菌;中海油天津为梭菌、芽孢杆菌和弧菌。在各油藏分布的异化铁还原菌,既有相同,也有差异。研究结果可为异化铁还原菌提高原油采收率提供基础。

To promote new enhance oil recovery from low permeability and water sensitive reservoirs,the samples were collected from low permeability reservoirs of Qinghai oilfield and Shengli oilfield,and from water sensitive ones of CNOOC Tianjin.Enrichment cultures for dissimilated iron reducing bacteria(DIRB)were conducted with amorphous ferric hydroxide as solid electron acceptors and mixed carbon sources as electron donors,and communities were revealed by high-throughput sequencing method.The results showed thatα-index of the enrichment cultures was significant reduced.Theβcluster showed that the communities of the enrichment cultures were highly correlated with that of the inoculation samples.The dominated DIRB distributed in Qinghai oilfield were Clostridia,Desulfovibrio,Shewanella,Pseudomonas and Thermotoga;in Shengli Oilfield were Clostridia,Thermoanaerobacter,Thermotoga and Deferribacter;and in CNOOC Tianjin were Clostridia,Bacillus and Vibrio.These results showed that these oil reservoirs shared some genera of DIRB,and also harbored some unique ones.These results could establish the foundation for DIRB enhance oil recovery.