当前位置： SCI文献检索 > Frontiers in Microbiology期刊下所有文献 > Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system.

Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system.

Abstract：

:Geological CO2 sequestration in unmineable subsurface oil/gas fields and coal formations has been proposed as a means of reducing anthropogenic greenhouse gasses in the atmosphere. However, the feasibility of injecting CO2 into subsurface depends upon a variety of geological and economic conditions, and the ecological consequences are largely unpredictable. In this study, we developed a new flow-through-type reactor system to examine potential geophysical, geochemical and microbiological impacts associated with CO2 injection by simulating in-situ pressure (0-100 MPa) and temperature (0-70°C) conditions. Using the reactor system, anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 ml/min, respectively) were continuously supplemented into a column comprised of bituminous coal and sand under a pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. 16S rRNA gene analysis of the bacterial components showed distinct spatial separation of the predominant taxa in the coal and sand over the course of the experiment. Cultivation experiments using sub-sampled fluids revealed that some microbes survived, or were metabolically active, under CO2-rich conditions. However, no methanogens were activated during the experiment, even though hydrogenotrophic and methylotrophic methanogens were obtained from conventional batch-type cultivation at 20°C. During the reactor experiment, the acetate and methanol concentration in the fluids increased while the δ(13)Cacetate, H2 and CO2 concentrations decreased, indicating the occurrence of homo-acetogenesis. 16S rRNA genes of homo-acetogenic spore-forming bacteria related to the genus Sporomusa were consistently detected from the sandstone after the reactor experiment. Our results suggest that the injection of CO2 into a natural coal-sand formation preferentially stimulates homo-acetogenesis rather than methanogenesis, and that this process is accompanied by biogenic CO2 conversion to acetate.

journal_name

Front Microbiol

journal_title

Frontiers in microbiology

authors

Ohtomo Y,Ijiri A,Ikegawa Y,Tsutsumi M,Imachi H,Uramoto G,Hoshino T,Morono Y,Sakai S,Saito Y,Tanikawa W,Hirose T,Inagaki F

doi

10.3389/fmicb.2013.00361

subject

Has Abstract

pub_date

2013-12-02 00:00:00

pages

361

issn

1664-302X

journal_volume

pub_type

杂志文章

在线工具

Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system.