A Multi-Continuum Multi-Component Model for Enhanced Gas Recovery and CO_2 Storage in Fractured Shale Gas Reservoirs

摘要

Shale gas reservoirs have been proposed as feasible choices of location for injection of CO_2 because this method could enhance recovery of natural gas resources, while at the same time sequester CO_2 underground. In this paper, a fully coupled multi-continuum multi-component simulator which incorporates several transport/storage mechanisms is developed. Knudsen diffusion and gas slippage are included in the flow model. An extended Langmuir isotherm is used to describe the adsorption/desorption behavior. In addition, a hierarchical approach which integrates EDFM with MINC concept is adopted. Fully implicit scheme is applied for discretizing fluid equations. Different injection strategies including huff-n-puff scenario are evaluated to provide insights for optimizing production of multi-fractured horizontal well. Results show that CO_2 injection can be an effective approach with great application potential for enhancing shale gas recovery.