RT Journal Article
ID 12116f667c42c4be
A1 Xiang, Zuping
A1 Liang, Hongbin
A1 Qi, Zhilin
A1 Xiao, Qianhua
A1 Yan, Wende
A1 Liang, Baosheng
A1 Guo, Qiutian
T1 MATHEMATICAL MODEL FOR ISOTHERMAL ADSORPTION OF SUPERCRITICAL SHALE GAS
JF Journal of Porous Media
JO JPM
YR 2019
FD 2019-03-29
VO 22
IS 4
SP 499
OP 510
K1 shale gas
K1 supercritical
K1 isothermal adsorption
K1 mathematical model
AB Shale gas adsorption under reservoir conditions belongs to supercritical adsorption in general, while the current adsorption models are constructed under subcritical conditions. Laboratory measurements of shale gas densities have demonstrated that temperature and pressure have a significant impact on supercritical shale gas density and therefore adsorption volume, leading to the importance of considering the influence of the supercritical state on the calculation of shale gas adsorption volume in the shale gas isothermal adsorption model. In this paper, we modified the Dubibin-Astakhov (D-A) model and built an isothermal adsorption mathematical model of supercritical shale gas using the change of bulk gas density to represent adsorption volume and replacing the saturated vapor pressure of the D-A
equation with the maximum pressure of supercritical adsorption determined from a linear method in the low-pressure region. Our examples show that the proposed model is a good fit with the data. The potential energy distribution on the absorbent surface calculated from the modified model illustrates that supercritical shale gas adsorption is performed inside micropores. When the temperature increases, the maximum adsorption volume of the micropores decreases and the adsorption phase density increases, while the characteristic adsorption energy is stable.
PB Begell House
LK http://dl.begellhouse.com/journals/49dcde6d4c0809db,3a1b1ba75698ac79,12116f667c42c4be.html