不同压力条件下油藏内源细菌群落激活过程中变性梯度凝胶电泳分析

Denature gradient gel electrophoresis of stratal bacteria activation in oilfield under different pressure conditions

【目的】了解常压(1MPa)和高压(10MPa)条件下内源细菌激活中的细菌群落和结构的变化。【方法】利用胜利油田沾3×24井产出液水样,在常压和高压下进行富集培养后,定时取样,样品用变性梯度凝胶电泳(denature gradient gel electrophoresis,DGGE)技术分析。【结果】通过对内源微生物激活前后DGGE条带的数量和亮度变化分析表明,油藏环境中的细菌在种类和数量上并不丰富,激活剂的加入改变了菌群原有的贫营养环境,从而使一些因营养缺乏生长受抑制细菌得以大量繁殖,菌群结构发生变化。【结论】高压条件下,条带数量变化趋势与常压下大体一致,但在条带数量和出现的位置上有所差异,高压条件下,DGGE条带数量要少一些,说明高压激活过程中能适应环境的细菌种类较少,且条带数量的增加相比常压具有明显的滞后性;激活后期,条带数量和亮度的变化逐渐趋缓,表明细菌群落生态结构重新调整,达到了新的动态平衡。论文的研究结果为解释微生物驱油室内研究与现场效果评价之间的关系奠定基础。

[Objective] To study the structure change of dominant microbial population during activation of strata1 microflora under atmospheric pressure （1 MPa） and higher pressure （10 MPa） conditions. [ Method] The water sample was from Zhan 3 × 24 well produced water in Shengli Oilfield. We activated the bacteria in the water sample under atmospheric pressure and higher pressure, and collected samples at different time intervals. These samples were analyzed by denature gradient gel electrophoresis （DGGE）. [ Results] Based on the analysis of the number and lightness of DGGE bands, we studied the change of the microbial community diversity activation of stratal bacteria. The species number and total quantity of dominant microbial population were not abundant under oil reservoir conditions. After injecting activation agent, some bacteria grew and reproduced quickly along with the enhancement of nutrition condition, and the structure of dominant microbial population changed. [ Conclusion] Compared to atmospheric pressure condition, the number of DGGE bands was fewer under higher pressure condition, which indicated that only a few microbial species adapted high pressure conditions. The delayed increase of DGGE bands occurred apparently under higher pressure conditions. In late activation period, the change of DGGE bands was slight, which indicated that, the structure of dominant microbial population readjusted successfully and reached a new dynamic balance. This paper lays the foundation for explaining the relationship between laboratory study and field effect evaluation of microbial flooding.