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Title: Geochemical investigation of the potential for mobilizing non-methane hydrocarbons during carbon dioxide storage in deep coal beds

Abstract

Coal samples of different rank (lignite to anthracite) were extracted in the laboratory with supercritical CO{sub 2} (40{sup o}C; 10 MPa) to evaluate the potential for mobilizing non-methane hydrocarbons during CO{sub 2} storage (sequestration) or enhanced coal bed methane recovery from deep ({approximately} 1-km depth) coal beds. The total measured alkane concentrations mobilized from the coal samples ranged from 3.0 to 64 g tonne{sup -1} of dry coal. The highest alkane concentration was measured in the lignite sample extract; the lowest was measured in the anthracite sample extract. Substantial concentrations of polycyclic aromatic hydrocarbons (PAHs) were also mobilized from these samples: 3.1-91 g tonne{sup -1} of dry coal. The greatest amounts of PAHs were mobilized from the high-volatile bituminous coal samples. The distributions of aliphatic and aromatic hydrocarbons mobilized from the coal samples also varied with rank. In general, these variations mimicked the chemical changes that occur with increasing degrees of coalification and thermal maturation. For example, the amount of PAHs mobilized from coal samples paralleled the general trend of bitumen formation with increasing coal rank. The coal samples yielded hydrocarbons during consecutive extractions with supercritical CO{sub 2}, although the amount of hydrocarbons mobilized declined with each successive extraction. Thesemore » results demonstrate that the potential for supercritical CO{sub 2} to mobilize non-methane hydrocarbons from coal beds, and the effect of coal rank on this process, are important to consider when evaluating deep coal beds for CO{sub 2} storage. 36 refs., 7 figs., 3 tabs.« less

Authors:
;  [1]
  1. U.S. Geological Survey, Reston, VA (United States)
Publication Date:
OSTI Identifier:
20741010
Resource Type:
Journal Article
Resource Relation:
Journal Name: Energy and Fuels; Journal Volume: 20; Journal Issue: 2; Other Information: jkolak@usgs.gov
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; GEOCHEMISTRY; HYDROCARBONS; CARBON DIOXIDE; UNDERGROUND STORAGE; CARBON SEQUESTRATION; COAL SEAMS; COAL RANK; SUPERCRITICAL GAS EXTRACTION; METHANE; ALKANES; POLYCYCLIC AROMATIC HYDROCARBONS

Citation Formats

Jonathan J. Kolak, and Robert C. Burruss. Geochemical investigation of the potential for mobilizing non-methane hydrocarbons during carbon dioxide storage in deep coal beds. United States: N. p., 2006. Web. doi:10.1021/ef050040u.
Jonathan J. Kolak, & Robert C. Burruss. Geochemical investigation of the potential for mobilizing non-methane hydrocarbons during carbon dioxide storage in deep coal beds. United States. doi:10.1021/ef050040u.
Jonathan J. Kolak, and Robert C. Burruss. Wed . "Geochemical investigation of the potential for mobilizing non-methane hydrocarbons during carbon dioxide storage in deep coal beds". United States. doi:10.1021/ef050040u.
@article{osti_20741010,
title = {Geochemical investigation of the potential for mobilizing non-methane hydrocarbons during carbon dioxide storage in deep coal beds},
author = {Jonathan J. Kolak and Robert C. Burruss},
abstractNote = {Coal samples of different rank (lignite to anthracite) were extracted in the laboratory with supercritical CO{sub 2} (40{sup o}C; 10 MPa) to evaluate the potential for mobilizing non-methane hydrocarbons during CO{sub 2} storage (sequestration) or enhanced coal bed methane recovery from deep ({approximately} 1-km depth) coal beds. The total measured alkane concentrations mobilized from the coal samples ranged from 3.0 to 64 g tonne{sup -1} of dry coal. The highest alkane concentration was measured in the lignite sample extract; the lowest was measured in the anthracite sample extract. Substantial concentrations of polycyclic aromatic hydrocarbons (PAHs) were also mobilized from these samples: 3.1-91 g tonne{sup -1} of dry coal. The greatest amounts of PAHs were mobilized from the high-volatile bituminous coal samples. The distributions of aliphatic and aromatic hydrocarbons mobilized from the coal samples also varied with rank. In general, these variations mimicked the chemical changes that occur with increasing degrees of coalification and thermal maturation. For example, the amount of PAHs mobilized from coal samples paralleled the general trend of bitumen formation with increasing coal rank. The coal samples yielded hydrocarbons during consecutive extractions with supercritical CO{sub 2}, although the amount of hydrocarbons mobilized declined with each successive extraction. These results demonstrate that the potential for supercritical CO{sub 2} to mobilize non-methane hydrocarbons from coal beds, and the effect of coal rank on this process, are important to consider when evaluating deep coal beds for CO{sub 2} storage. 36 refs., 7 figs., 3 tabs.},
doi = {10.1021/ef050040u},
journal = {Energy and Fuels},
number = 2,
volume = 20,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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