Differences in microbial community composition between injection and production water samples of water flooding petroleum reservoirs

Abstract

Abstract. Microbial communities in injected water are expected to have significant influence on those of reservoir strata in long-term water flooding petroleum reservoirs. To investigate the similarities and differences in microbial communities in injected water and reservoir strata, high-throughput sequencing of microbial partial 16S rRNA of the water samples collected from the wellhead and downhole of injection wells, and from production wells in a homogeneous sandstone reservoir and a heterogeneous conglomerate reservoir were performed. The results indicate that a small number of microbial populations are shared between the water samples from the injection and production wells in the sandstone reservoir, whereas a large number of microbial populations are shared in the conglomerate reservoir. The bacterial and archaeal communities in the reservoir strata have high concentrations, which are similar to those in the injected water. However, microbial population abundance exhibited large differences between the water samples from the injection and production wells. The number of shared populations reflects the influence of microbial communities in injected water on those in reservoir strata to some extent, and show strong association with the unique variation of reservoir environments.

Spatial isolation and environmental factors drive distinct bacterial and archaeal communities in different types of petroleum reservoirs in China

“…As a result, we found that even in the same reservoir block, only a small number of microbial organisms were observed across the water samples from different production wells in the same reservoir. This phenomenon has also been documented by analysing the microbial communities derived from the wellhead and downhole of injection wells, and from their effective production wells nearby 20 .…”

“…Diverse microbial community structures in the production wells from the same reservoir were also observed. The differences observed may be related to the isolation of the oil-bearing strata, the depth span of the reservoir strata 1 20 23 , and/or stochastic processes 28 54 . The spatial isolation and low permeability of reservoir strata may exert a significant influence on the community composition and structure in oil wells, even those located the same reservoir block.…”

“…Some studies have enhanced the potential for biotechnological applications, in particular, the use of biological preservatives 10 11 12 13 and microbial enhanced oil recovery 14 15 . Diverse microbial populations inhabiting these reservoirs have been revealed 16 17 18 19 20 21 22 23 . However, due to limited sample sources and methodological constraints, few studies have attempted to characterize the large-scale biogeographic distributions of microbial communities in oil reservoirs.…”

An Exogenous Surfactant-Producing Bacillus subtilis Facilitates Indigenous Microbial Enhanced Oil Recovery

“…Petroleum reservoirs represent special environments underground with low permeability. Owing to the sieve effect on microbial cells when injected fluid passes through a subsurface formation, the injected exogenous microorganisms may not migrate into the reservoir formation ( Youssef et al, 2009 ; Gao et al, 2015a ; Ren et al, 2015 ). Youssef et al (2007) injected B. licheniformis , B. subtilis subsp.…”

“…The drawback is that these microorganisms must be able to grow in the presence of competing indigenous populations ( Bryant, 1991 ). Furthermore, because of the sieve effect of strata on microbial cells, the injected microorganisms are generally difficult to migrate into reservoir strata to reach the production wells ( Youssef et al, 2009 ; Gao et al, 2015a ; Ren et al, 2015 ). Indigenous microbial flooding is another promising oil-recovery technique that has been successfully applied in the petroleum industry ( Belyaev et al, 1998 ; Liu et al, 2005 ; Li et al, 2014 ; Wang et al, 2014b ; Le et al, 2015 ).…”