不同水分煤样吸附甲烷的极限吸附量预测

以大佛寺4#不粘煤样为研究对象,进行4#不粘煤空气干燥基样和平衡水分样等温吸附实验,计算吸附势和吸附空间,得出吸附特征曲线,以期预测大佛寺4#不粘煤层中煤层气资源/储量,验证吸附理论的可靠性。实验结果显示:对于同1种煤样,吸附势与环境温度无关系,煤中水分大小对吸附势影响较大;实验进一步证明煤-甲烷分子之间作用力主要为色散力,吸附过程为物理吸附;根据吸附特征曲线计算所得极限吸附量与常规Langmuir方程拟合所得结果十分相近,初步证明吸附特征曲线所得极限吸附量预测煤吸附甲烷最大能力、预测煤层气资源/储量是可行的方法。

Prediction on Utmost Adsorption Quantity of Methane in Coal Samples with Different Water Content

Taking 4#non-caking coal sample in Dafosi as the research object, isothermal adsorption experiment is conducted between the air drying base sample and equilibrium water moisture sample of4#non-caking coal, also the adsorption potential and adsorption space are calculated, in order to predict the coalbed methane resources or reserves of 4#non-caking coalbed in Dafosi for verifying the reliability of adsorption theory. The experiment result shows that: for the same kind of coal sample,adsorption potential is not associated with environmental temperature, but moisture size does have a great influence on adsorption potential; experiment further proves that the main acting force among the coal-methane molecules is dispersion force, and it is a physical adsorption process; ultimate adsorption quantity based on the adsorption characteristic curve is very close with the result of the general Langmuir equation fitting, which preliminarily testifies that ultimate adsorption quantity from the adsorption characteristic curve can viably predict the maximum adsorption capacity for methane of coal as well as the coalbed methane resources or reserves.