Development of a multi-mechanistic, dual-porosity, dual-permeability, numerical flow model for coalbed methane reservoirs

作者：Thararoop Prob; Karpyn Zuleima T; Ertekin Turgay^*

来源：Journal of Natural Gas Science and Engineering, 2012, 8: 121-131.

DOI：10.1016/j.jngse.2012.01.004

• Coalbed methane simulation
• Dual-porosity dual-permeability model
• Multi-mechanistic gas flow
• Water in the coal matrix
• Coal shrinkage and swelling
• Enhanced coalbed methane recovery

Most existing coalbed methane (CBM) simulators usually treat coal seams as dual-porosity, single-permeability systems ignoring the effects of water presence in the coal matrix. In this study, a compositional dual-porosity, dual-permeability CBM simulator has been developed. The CBM reservoir is treated as a dual-porosity, dual-permeability system consisting of coal matrix and fracture network. The development of the proposed numerical model incorporates the effects of water presence in the coal matrix and the phenomena of coal shrinkage and swelling. The transport of gas follows a multi-mechanistic flow mechanism triggered by pressure and concentration gradients. In addition, the proposed simulator is able to collapse to simpler coal seam representations and was successfully tested against the existing commercial and research CBM simulators for CO2-enhanced CBM recovery process. Successful history matching exercises were performed on pure CO2 injection and flue gas injection tests using the actual field data.

• 出版日期2012-9