Predicting adsorbed gas capacity of deep shales under high temperature and pressure: Experiments and modeling

Temperature and pressure conditions of deep shale are beyond experiment range, the amount adsorbed gas is difficult to determine. To predict content shales under formation conditions, isothermal adsorption experiments model building were conducted on samples from Longmaxi Formation in China. A temperature-dependent based Langmuir equation proposed, which can be well-fitted by observed isotherms with a high correlation coefficient. Based fitted parameters at 303.15 K, curves 333.15 363.15 393.15 K predicted, showing good agreement experimental available. Compared previous prediction methods, biggest advantage proposed method that it carried out only one-time experiment. predictions, downward trend excess will slow down temperature when reaches certain level (> 80 MPa), has little effect capacity. While for absolute adsorption, saturation much slowly temperature, also reach pressure. Under burial depth marine shale, plays major role controlling gas, resulting decrease its ratio further as increases. Cited as: Zhou, S., Wang, H., Li, B., Sepehrnoori, K., Cai, J. Predicting capacity pressure: Experiments modeling. Advances Geo-Energy Research, 2022, 6(6): 482-491. https://doi.org/10.46690/ager.2022.06.05