Enhanced coalbed methane recovery by the modification of coal reservoir under the supercritical CO2 extraction and anaerobic digestion

Weizhong Zhao, Xianbo Su, Daping Xia, Shihui Hou, Qian Wang and Yixuan Zhou

Energy, 2022, vol. 259, issue C

Abstract: Coal reservoir is considered as the ideal site for coalbed methane (CBM) occurrence, biomethanation and CO2 sequestration. Four coal samples with different ranks were selected to conduct supercritical CO2 (Sc-CO2) extraction and anaerobic digestion (AD). X-ray photoelectron spectroscopy, mercury intrusion, and isothermal adsorption experiments were performed on the raw coal samples and the remaining coal samples after Sc-CO2 and Sc–CO2–AD to analyze the mechanism of enhanced CBM recovery by reservoir modification. The results showed that coal pore volume and porosity are greatly increased after Sc-CO2 extraction. Meanwhile, the reduction of the oxygen-containing functional groups and the micropore specific surface area determined the weakening of the adsorption capacity of coal. After Sc–CO2–AD, the macropore volume and porosity of coal continued to increase, and the permeability of coal was effectively improved. And the oxygen-containing functional groups and micropore specific surface area continued to decrease, which determined that the adsorption capacity of coal for methane continued to decrease. Sc-CO2 and AD can mutually promote the modification of coal reservoirs. These effects are quite favorable for gas desorption, migration and production during CBM exploitation, which provide powerful supports for CO2 emission reduction, CO2 geological sequestration and CBM production enhancement.

Keywords: Sc-CO2 extraction; Anaerobic digestion; Reservoir modification; Coalbed methane stimulation; CO2 emission reduction (search for similar items in EconPapers)
Date: 2022
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (4)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544222018151
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:259:y:2022:i:c:s0360544222018151

DOI: 10.1016/j.energy.2022.124914

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().