Cargando…

Changes in pore structure of coal caused by coal-to-gas bioconversion

Microbial enhanced coalbed methane (ME-CBM) recovery is critically examined as a viable technology for natural gas recovery from coalbed methane (CBM) reservoirs. Since the majority of gas-in-place (GIP) is stored as an adsorbed phase in fine pores of coal matrix, the nano-pore structure directly in...

Descripción completa

Detalles Bibliográficos
Autores principales: Zhang, Rui, Liu, Shimin, Bahadur, Jitendra, Elsworth, Derek, Wang, Yi, Hu, Guanglong, Liang, Yanna
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5476654/
https://www.ncbi.nlm.nih.gov/pubmed/28630465
http://dx.doi.org/10.1038/s41598-017-04110-z
_version_ 1783244632125079552
author Zhang, Rui
Liu, Shimin
Bahadur, Jitendra
Elsworth, Derek
Wang, Yi
Hu, Guanglong
Liang, Yanna
author_facet Zhang, Rui
Liu, Shimin
Bahadur, Jitendra
Elsworth, Derek
Wang, Yi
Hu, Guanglong
Liang, Yanna
author_sort Zhang, Rui
collection PubMed
description Microbial enhanced coalbed methane (ME-CBM) recovery is critically examined as a viable technology for natural gas recovery from coalbed methane (CBM) reservoirs. Since the majority of gas-in-place (GIP) is stored as an adsorbed phase in fine pores of coal matrix, the nano-pore structure directly influences gas storage and transport properties. Only limited studies have quantified the alteration of the nano-pore structure due to ME-CBM treatment. This study examines the evolution of the pore structure using a combination of small angle X-ray scattering (SAXS), low-pressure N(2) and CO(2) adsorption (LPGA) and high-pressure methane adsorption methods. The results show that the surface fractal dimension decreases for the two bioconverted coals compared to the untreated coal. After bio-treatment, the mesopore surface area and pore volume decrease with the average pore diameter increases, while the micropore surface area increases with pore volume decreases. Both inaccessible meso-/micropore size distributions decrease after bioconversion, while the accessible micropore size distribution increases, making a portion of closed micropore network accessible. In addition, the methane adsorption capacities increase after bio-treatment, which is confirmed by the increase of micropore surface area. A conceptual physical model of methanogenesis is proposed based on the evolution of the pore structure.
format Online
Article
Text
id pubmed-5476654
institution National Center for Biotechnology Information
language English
publishDate 2017
publisher Nature Publishing Group UK
record_format MEDLINE/PubMed
spelling pubmed-54766542017-06-23 Changes in pore structure of coal caused by coal-to-gas bioconversion Zhang, Rui Liu, Shimin Bahadur, Jitendra Elsworth, Derek Wang, Yi Hu, Guanglong Liang, Yanna Sci Rep Article Microbial enhanced coalbed methane (ME-CBM) recovery is critically examined as a viable technology for natural gas recovery from coalbed methane (CBM) reservoirs. Since the majority of gas-in-place (GIP) is stored as an adsorbed phase in fine pores of coal matrix, the nano-pore structure directly influences gas storage and transport properties. Only limited studies have quantified the alteration of the nano-pore structure due to ME-CBM treatment. This study examines the evolution of the pore structure using a combination of small angle X-ray scattering (SAXS), low-pressure N(2) and CO(2) adsorption (LPGA) and high-pressure methane adsorption methods. The results show that the surface fractal dimension decreases for the two bioconverted coals compared to the untreated coal. After bio-treatment, the mesopore surface area and pore volume decrease with the average pore diameter increases, while the micropore surface area increases with pore volume decreases. Both inaccessible meso-/micropore size distributions decrease after bioconversion, while the accessible micropore size distribution increases, making a portion of closed micropore network accessible. In addition, the methane adsorption capacities increase after bio-treatment, which is confirmed by the increase of micropore surface area. A conceptual physical model of methanogenesis is proposed based on the evolution of the pore structure. Nature Publishing Group UK 2017-06-19 /pmc/articles/PMC5476654/ /pubmed/28630465 http://dx.doi.org/10.1038/s41598-017-04110-z Text en © The Author(s) 2017 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
spellingShingle Article
Zhang, Rui
Liu, Shimin
Bahadur, Jitendra
Elsworth, Derek
Wang, Yi
Hu, Guanglong
Liang, Yanna
Changes in pore structure of coal caused by coal-to-gas bioconversion
title Changes in pore structure of coal caused by coal-to-gas bioconversion
title_full Changes in pore structure of coal caused by coal-to-gas bioconversion
title_fullStr Changes in pore structure of coal caused by coal-to-gas bioconversion
title_full_unstemmed Changes in pore structure of coal caused by coal-to-gas bioconversion
title_short Changes in pore structure of coal caused by coal-to-gas bioconversion
title_sort changes in pore structure of coal caused by coal-to-gas bioconversion
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5476654/
https://www.ncbi.nlm.nih.gov/pubmed/28630465
http://dx.doi.org/10.1038/s41598-017-04110-z
work_keys_str_mv AT zhangrui changesinporestructureofcoalcausedbycoaltogasbioconversion
AT liushimin changesinporestructureofcoalcausedbycoaltogasbioconversion
AT bahadurjitendra changesinporestructureofcoalcausedbycoaltogasbioconversion
AT elsworthderek changesinporestructureofcoalcausedbycoaltogasbioconversion
AT wangyi changesinporestructureofcoalcausedbycoaltogasbioconversion
AT huguanglong changesinporestructureofcoalcausedbycoaltogasbioconversion
AT liangyanna changesinporestructureofcoalcausedbycoaltogasbioconversion