Biogenic coal-to-methane conversion can be enhanced with small additions of algal amendment in field-relevant upflow column reactors

FUEL

卷:256

Article

Davis, Katherine J.^1,2  Platt, George A.^1,2  Barnhart, Elliott P.^1,3  Hiebert, Randy⁴  Hyatt, Robert⁴  Fields, Matthew W.^1,5  Gerlach, Robin^1,2 

[1] Montana State Univ, Ctr Biofilm Engn, Bozeman, MT 59717 USA

[2] Montana State Univ, Dept Chem & Biol Engn, Bozeman, MT 59717 USA

[3] US Geol Survey, Helena, MT 59601 USA

[4] Montana Emergent Technol, Butte, MT 59701 USA

[5] Montana State Univ, Dept Microbiol & Immunol, Bozeman, MT 59717 USA

关键词: Coalbed methane (CBM);    Methane enhancement;    Stable isotope;    Powder River Basin;    Field-relevance;    Algae;   

DOI  :  10.1016/j.fuel.2019.115905

来源: Elsevier

【 摘 要 】

Subsurface coal environments, where biogenic coal-to-methane conversion occurs, are difficult to access, resulting in inherent challenges and expenses for in situ experiments. Previous batch reactor studies provided insights into specific processes, pathways, kinetics, and engineering strategies, but field-relevance is restricted due to limited substrate availability or byproduct accumulation that may influence reactions or metabolisms. In this study, continuous-flow column reactors were used to overcome some batch limitations, improve the understanding of in situ conditions, and increase field-relevance for subsurface engineering technology development. The bench-scale reactor system was constructed to investigate the addition of algal amendment for enhancing microbial coal-to-methane conversion previously developed in batch systems. Four reactor columns were packed with coal and inoculated with a microbial consortium from the same Flowers-Goodale coal bed. Two reactors were amended with C-13-labeled algal amendment on day 0, and two were unamended. On day 61, one previously amended and one previously unamended reactor were re-amended. Produced gases were captured in a gas trap, and CH4 and CO2 were quantified. The reactor amended twice produced 1712.6 mu mol CH4 (4.6% as (CH4)-C-13). The reactor amended only on day 0 produced 1485.5 mu mol CH4(2.6% as (CH4)-C-13). The reactor amended only on day 61 produced 278.9 mu mol CH4(3.9% as (CH4)-C-13). The reactor with no amendment produced no measurable gases for the duration of the 172-day experiment. Amendment increased the rate of coal-tomethane conversion and total gas production; most of the produced gases were due to coal conversion with only small contributions (< 7%) from amendment conversion.

【 授权许可】

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