深部煤层赋存环境温度及对瓦斯吸附影响微观机制

Ambient Temperature of Deep Coal Seam and Influence on Gas Adsorption Micro-mechanism

为探究深部煤层赋存环境温度变化及对瓦斯吸附的影响,在研究地温变化规律的基础上,预测了深部煤层赋存环境温度,通过高压容量法测试了5组不同温度下吸附常数,从理论上分析了温度对分子热运动的作用效应,利用Materials Studio软件模拟了5组不同温度下的平均吸附热绝对值。研究结果表明:随着埋藏深度的增加,煤层赋存环境温度呈线性升高;随着温度的升高,吸附常数a呈线性减小,吸附常数b呈现出阶段性变化,在30℃~120℃变化较小,高于120℃后迅速增大;环境温度升高,分子热运动加剧,增加了甲烷分子的脱附速度;平均瓦斯吸附热的绝对值随着温度的升高线性增大,增加了瓦斯吸附难度,降低了瓦斯吸附量。

In order to explore the temperature change of the deep coal seam and its influence on gas adsorption, based on the study of the law of ground temperature, the temperature of the deep coal seam was predicted, and 5 sets of adsorption constants at different temperatures were tested by the high pressure volumetric method. The above analyzes the effect of temperature on the thermal motion of molecules, using Materials Studio software to simulate the absolute value of the average heat of adsorption at 5 groups of different temperatures. The research results show that with the increase of burial depth, the temperature of the coal seam storage environment increases linearly;with the increase of temperature, the adsorption constant a decrease linearly, and the adsorption constant b presents a stage change. From 30 ℃ to 120 ℃, the change between is small, and it increases rapidly when the temperature is higher than 120 ℃;when the ambient temperature rises, the molecular thermal movement intensifies, which increases the desorption rate of methane molecules;the absolute value of the average gas adsorption heat increases linearly with the increase in temperature Large, increasing the difficulty of gas adsorption and reducing the amount of gas adsorption.