不同吸附模型对容量法、重量法测定页岩吸附等温曲线的拟合分析

Analysis on model fitting of adsorption isotherms in shales tested by volumetric method and gravimetric method

摘要: 采用容量法、重量法对随机选取的12个页岩样品在不同温度进行等温吸附测试。使用Freundlich,Langmuir,D-R,Langmuir-Freundlich,Double Langmuir,Toth等6种常用的单组分拟合模型对实验数据进行拟合,检验了实验数据的拟合程度。结果表明:综合考虑不同样品、温度、平衡压力及实验方法,拟合结果由好到差的顺序为:Langmuir-Freundlich,Double Langmuir,Toth,D-R,Freundlich,Langmuir。其中,Langmuir-Freundlich、双Langmuir分别在平衡压力较高、较低的实验条件下拟合最为精确。

Abstract: The adsorption isotherms test at different temperatures on 12 shale samples selected randomly was conducted using volumetric method and gravimetric method. Six different single-component fitting models (Freundlich,Langmuir, D-R,Langmuir-Freundlich,double Langmuir,Toth) were used to fit the experimental data,and their fitting degree was investigated. Considering different samples,temperature,equilibrium pressure and experimental methods,the results show that the fitting result order from good to badis:Langmuir-Freundlich,double Langmuir,Toth,D-R,Freundlich, and Langmuir. Among them,the Langmuir-Freundlich equation and double Langmuir equation could describe the curve most accurately under the condition of higher equilibrium pressure and lower experiment condition respectively.