Displacement behavior of CH4 adsorbed on coals by injecting pure CO2, N2, and CO2–N2 mixture

Sorption of carbon dioxide, methane and nitrogen in dry coals at high pressure and moderate temperature

“…In the case of CH 4 , the isotherms exhibit also a maximum, though less pronounced, whereas for N 2 this is not visible, the measuring conditions being far above the critical temperature. It is well known that coal has a higher sorption capacity for CO 2 compared to CH 4 , and even more compared to N 2 (Fitzgerald et al, 2005;Shimada et al, 2005;Bae and Bhatia, 2006;Sakurovs et al, 2007). This behavior, which has also been observed for all the coals tested here, is a prerequisite for a successful ECBM operation.…”

Permeability evolution in fractured coal: The roles of fracture geometry and water-content

“…This ratio decreases with increasing temperature (Bae and Bhatia, 2006;Li et al, 2010). The sorption capacity ratios of CO 2 to N 2 are found to be between 2:1 and 8.5:1 (Battistutta et al, 2010;Saghafi et al, 2007;Shimada et al, 2005). However, some coals under certain conditions show a larger sorption capacity to CH 4 than to CO 2 (Busch et al, 2003;Busch et al, 2006;Majewska et al, 2009).…”

Competitive adsorption equilibria of CO2 and CH4 on a dry coal

“…In addition, an extensive set of high-pressure adsorption data of CO 2 , CH 4 and N 2 and their mixtures on three water-moistened coals, namely Fruitland, Tiffany and Illinois, was reported, and the data were described using a simplified local-density model (Fitzgerald et al 2005;Fitzgerald and Robinson 2006). The displacement of CH 4 adsorbed on coals by injecting either pure CO 2 , pure N 2 or CO 2 /N 2 mixtures was investigated on a dried Japanese coal sample (Shimada et al 2005), and CO 2 -CH 4 binary adsorption measurements on two types of Polish coal have also been reported (Ceglarska-Stefanska and Zarebska 2005). Finally, the adsorption of pure CO 2 and a flue gas (containing mainly nitrogen, carbon dioxide, hydrogen and methane) on a coal sample from the Silesian Basin in Poland in dry and wet state was recently investigated, showing that CO 2 was the most and CH 4 the second most preferred component adsorbed (Mazumder et al 2006).…”