超临界状态下构造煤甲烷等温吸附模型研究

Methane Isothermal Adsorption Model in Tectonic Coal under Supercritical State

为了表征构造煤超临界吸附特征,准确预测深部煤层瓦斯含气量,进行容量法等温吸附实验。依据Langmuir、BET、D-A、D-R模型对绝对吸附量进行非线性拟合。比较各模型对整体吸附过程和甲烷临界压力之后吸附数据的拟合效果。结果表明:Langmuir模型和D-R模型可近似拟合吸附量数据,但精度不高,BET模型不适合用于描述构造煤超临界吸附特征,D-A超临界吸附模型拟合效果最好且能够合理地解释构造煤超临界吸附特征。

In order to characterize the supercritical adsorption characteristics of tectonic coal and accurately predict the gas content of deep coal seam,and the absolute adsorption capacity was nonlinearly fitted according to Langmuir,BET,D-A and D-R models.The fitting effects of the adsorption data were compared between the model and the overall adsorption process and the critical pressure of methane.The results show that the Langmuir model and the D-R model can approximate the adsorption capacity data,but the accuracy is not high,The BET model is not suitable for describing the supercritical properties of tectonic coal,and the D-A supercritical adsorption model has the best fitting effect and can explain the supercritical adsorption characteristics of tectonic coal reasonably.