Experimental Study on Effective Permeability of Supercritical CO2/CH4 Mixture Fluid in Coal
Year: 2025
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide For CO 2 enhanced CH 4 recovery in the coal seam, whose effective permeability would change with the different phase CO 2 . To evaluate this, a steady-state seepage test method was used to conduct the permeability tests under varying multiphase and multi-component CO 2 /CH 4 mixture fluid. The mixture permeability of gaseous or supercritical CO 2 + CH 4 under different fractions decreases with respect to the CO 2 concentration increasing. Meanwhile, the mixture permeability first decreases and then increases with the increasing injection pressure, and there is an obvious slippage effect when the injection pressure is lower than 3 MPa. The established permeability model values are in good agreement with the experimental data. The coal deformation accords with the Langmuir equation in the seepage process of CO 2 + CH 4 mixture under in situ conditions, and the two equation parameters (ε L, P L ) have a good linear relationship with CO 2 concentration. The CH 4 concentration in the outlet increases about 24.5% in the supercritical CO 2 + CH 4 mixture but less dramatic only about 8.5% in the gaseous CO 2 + CH 4 mixture. At the same time, the gaseous CO 2 (or CH 4 ) effective permeability increases (decreases) with increasing gaseous CO 2 concentration, while the supercritical CO 2 or CH 4 effective permeability basically remains unchanged with increasing supercritical CO 2 concentration. This study is meaningful for the prediction of mixed fluid permeability in the process of the CO 2 displacement exploitation of CH 4 .
Source: ACS Omega
Authors: Hongbo Yao, Dongsheng Hou
Institution: Shanxi College of Technology
Language: English
Subfield: Ocean Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,935
OpenAlex ID: W4411201411