不同温度与压力下瓦斯的吸附-热力学特性研究  

Adsorption-thermodynamic characteristics of methane at different temperatures and pressures conditions

作　　者：李波波[1,2,3] 高政 李建华 任崇鸿 王斌 张尧[1] LI Bo-bo;GAO Zheng;LI Jian-hua;REN Chong-hong;WANG Bin;ZHANG Yao(College of Mining,Guizhou University,Guiyang 550025,China;National&Local Joint Laboratory of Engineering for Effective Utilization of Regional Mineral Resources from Karst Areas,Guizhou University,Guiyang 550025,China;Guizhou Key Laboratory of Comprehensive Utilization of Non-metallic Mineral Resources,Guiyang 550025,China)

机构地区：[1]贵州大学矿业学院,贵阳550025 [2]贵州大学喀斯特地区优势矿产资源高效利用国家地方联合工程实验室,贵阳550025 [3]贵州省非金属矿产资源综合利用重点实验室,贵阳550025

出　　处：《安全与环境学报》2021年第6期2479-2488,共10页Journal of Safety and Environment

基　　金：国家自然科学基金项目(52064007,51804085,51911530203)。

摘　　要：为研究不同温度和气体压力下煤岩吸附瓦斯行为及热力学特性,考虑真实气体行为和吸附相的影响,进一步修正L-F模型以量化煤岩吸附能力,通过不同温度和压力条件吸附数据验证新修正吸附模型的适用性。并以此计算煤岩等量吸附热,探讨温度和气体压力(吸附量)对等量吸附热的影响。结果表明,新修正的吸附模型能较好地表征低、中、高气体压力试验范围下的等温吸附行为,且较原L-F模型能够更精确地预测其他条件吸附量。煤岩吸附瓦斯过程中等量吸附热的绝对值随温度和吸附量升高均呈降低趋势,但气体压力处于亨利定律区域时,其对应等量吸附热并未展现出对温度和吸附量的依赖性,该值可作为评价煤岩在低压区域内吸附瓦斯亲和力的唯一指标。Gas is a high-risk factor threatening the safety of coal mines.To study the gas adsorption behaviors and thermodynamic characteristics of coal under different temperatures and gas pressures,the L-F model was modified to quantify the adsorption capacity of coal by considering the real gas law and the effect of the adsorbed phase,and the applicability of the newly modified adsorption model was verified by adsorption dates under different temperature and pressure conditions.Meanwhile,the predictions of the adsorption isotherms under other test conditions of the original L-F model and the newly modified adsorption model were compared.Then the isosteric heat of adsorption of coal was further calculated,and the effects of temperature and pressure(adsorption amount) on the isosteric heat of adsorption were discussed.The results show that the new modified adsorption model can better characterize the isothermal adsorption behaviors under the test range of low,medium,and high gas pressure,and be more accurate to predict the adsorption capacity under other conditions than the original L-F model.In all test temperature and pressure ranges,the density of the gas adsorption phase calculated in this paper is always higher than that of the free phase and lower than that of liquid methane(26.33 mmol/cm^(3)).In the process of gas adsorption by coal,the isosteric heat of adsorption is an important thermodynamic parameter reflecting the interaction between coal and gas molecules.And the absolute value of isosteric heat of adsorption decreases with increasing temperature and adsorption capacity.However,when the gas pressure is within Henry’s law,the isosteric heat of absorption does not depend on temperature and adsorption amount.This value can be regarded as the only indicator to evaluate the adsorption appetency of gas by coal in the area of low pressure.

关 键 词：安全工程 煤岩 吸附 温度 等量吸附热 亨利定律 

分 类 号：X936[环境科学与工程—安全科学]