摘要
为研究热对煤体吸附/解吸瓦斯的作用效果及影响程度,在高压气体吸附仪的基础上,使用外接的恒温水浴装置,对潘三煤矿11-2煤层煤样进行不同温度下的甲烷吸附/解吸试验研究。结果表明:相同温度条件下,甲烷气体吸附量随着压力的增加而增大,但增加幅度逐渐降低;相同气体压力条件下,甲烷气体吸附量与温度之间呈非线性负相关关系,而且降低幅度逐渐增大;将气体压力修正系数引入到Langmuir方程之后,对不同温度条件下煤样吸附数据拟合,发现与传统的Langmuir方程相比,修正后的Langmuir方程拟合曲线的相关系数更高,而且拟合回归得到的吸附常数a、b的标准误差更小;在Langmuir方程修正模型基础上对不同温度条件下的吸附常数a、b及修正系数c进行了多项式拟合,得到煤吸附甲烷含量与温度、压力之间的耦合方程;试验得到的同一温度条件下煤样对甲烷的吸附和解吸曲线不重合,说明煤样对甲烷的解吸过程滞后于吸附过程,随着试验温度升高,吸附和解吸2条曲线间距越小,表明煤对甲烷的解吸滞后性越弱;利用吸附/解吸滞后评价模型定量计算了不同温度下的吸附/解吸滞后量,通过曲线拟合得到解吸滞后量与温度呈现负指数关系;从吸附热角度进一步揭示了解吸滞后于吸附的原因是吸附热小于解吸热,而且随着温度升高,煤对甲烷吸附/解吸热差值越小,从而导致煤解吸甲烷滞后量也越小。
In order to study the influence of heat on coal adsorption and desorption of gas and its degree,a high-pressure gas adsorption ap⁃paratus and thermostatic water bath device were used to conduct methane adsorption/desorption experiments on No.11-2 coal samples in Pan 3 Coal Mine under different constant temperature environments.The results show that the amount of methane adsorption increases with the increase of methane pressure under the same temperature,but the increase gradually decreases.Under the same gas pressure,the a⁃mount of methane adsorption decreases with the increase of temperature.The Langmuir equation is introduced a correction coefficient to the gas pressure,and then fit the experimental data of coal adsorption methane at different constant temperatures.It is found that compared with the traditional Langmuir equation,the correlation coefficient of the modified Langmuir equation fitting curve is higher,and the standard errors of the adsorption constants a,b obtained by the combined regression are smaller.On the basis of the Langmuir equation correction model,the adsorption constants a,b and the correction coefficient c at different experimental temperatures are polynomial fitting to obtain the model of the coal adsorption methane content and temperature and pressure.The experiment shows that the adsorption and desorption curves of coal for methane at the same temperature do not overlap,and the desorption lags behind the adsorption.The higher the tempera⁃ture,the smaller the distance between the adsorption and desorption curves,which indicates the weaker desorption hysteresis of methane by coal.The adsorption/desorption hysteresis evaluation model is used to quantitatively calculate the desorption hysteresis at different temper⁃atures,and it is a negative exponential relationship between the amount of desorption hysteresis and temperature by curve fitting.From the perspective of adsorption heat,it is further revealed that the reason of for the desorption hysteresis is that the heat of adsorption is less than the heat of desorption,and the difference between the adsorption/desorption heat of coal to methane is smaller as the temperature increa⁃ses,which leads to the smaller the amount of desorption hysteresis.
作者
唐明云
张海路
段三壮
姚冠霖
郑春山
张亮伟
TANG Mingyun;ZHANG Hailu;DUAN Sanzhuang;YAO Guanlin;ZHENG Chunshan;ZHANG Liangwei(State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan 232001,China;School of Safety Science and Engineering,Anhui University of Science and Technology,Huainan 232001,China)
出处
《煤炭科学技术》
CAS
CSCD
北大核心
2021年第5期182-189,共8页
Coal Science and Technology
基金
国家自然科学基金资助项目(51774014,51904013)。
关键词
气体压力
温度
吸附热
Langmuir修正方程
解吸滞后量
gas pressure
temperature
heat of adsorption
correction of Langmuir equation
amount of desorption hysteresis
