CO2 Injection in Coal Formations for Enhanced Coalbed Methane and CO2 Sequestration

This chapter investigates the ability of CO2 sequestration in coal formations, and the effect of different parameters on the process behavior. It presents experimental results for adsorption isotherm, wettability behavior, and injectivity in coal formations, and then provides conclusions based on those results. The chapter presents the characterization of the coal formations, the CO2, N2, and CH4 adsorption, wettability coal surface, CO2 injectivity, and a different pilot field test for enhanced coalbed methane (ECBM) process. In the ECBM process, nitrogen, CO2, or their binary mixtures are injected into coalbeds to be adsorbed on the coal surface and replace the CH4, CO2, or N2 adsorption, and CH4 desorption affect the coal permeability. CO2 can be sequestrated in coal seams to enhance the ECBM process in addition to CO2 storage. The efficiency of this process is greatly affected by the coal formation properties and the operation conditions.