不同粒径下煤样瓦斯吸附热力学特性影响实验研究

发布时间：2018-11-08 12:13

【摘要】：为揭示不同粒径下煤样的瓦斯吸附热力学特性,选择典型矿井煤样进行不同粒径、温度条件下的瓦斯等温吸附实验,利用Clausius-Clapeyron方程计算出各煤样等量吸附热;根据Langmuir方程建立了含标准平衡压力常数的瓦斯吸附自由能方程,得到其吸附自由能;通过Gibb-Helmholtz方程获得各煤样的吸附熵。研究结果表明:不同粒径、温度影响因素下的煤体瓦斯吸附过程依旧可用Langmuir方程表征;不同粒径煤样瓦斯等量吸附热、吸附自由能和吸附熵均小于0,变化范围分别为-14.19~-22.27 k J/mol、-4.83~-6.72 k J/mol和-28.20~-51.32 J/(mol·K);随着粒径增大,煤样瓦斯等量吸附热、吸附自由能、吸附熵均增大;随着温度升高,煤样瓦斯吸附自由能、吸附熵逐渐降低。实验结果表明,煤体瓦斯吸附过程是一种放热、自发、熵减小的物理吸附过程。
[Abstract]:In order to reveal the thermodynamic characteristics of gas adsorption of coal samples with different particle sizes, the isothermal adsorption experiments of coal samples with different particle sizes and temperatures were carried out, and the adsorption heat of each coal sample was calculated by Clausius-Clapeyron equation. According to the Langmuir equation, the gas adsorption free energy equation with standard equilibrium pressure constant was established, and the adsorption entropy of each coal sample was obtained by Gibb-Helmholtz equation. The results show that the adsorption process of coal gas under the influence of different particle size and temperature can still be characterized by Langmuir equation. The adsorption free energy and adsorption entropy of coal samples with different particle sizes are less than 0, ranging from -14.19 ~ 22.27 k / mol ~ (-1) J / m ~ (-1) to 4.83 ~ (3) ~ 6.72 k J/mol and -28.20 ~ (-1) ~ 51.32 J / (mol K);, respectively. With the increase of particle size, the adsorption heat, adsorption free energy and adsorption entropy of coal sample gas increase, and with the increase of temperature, the adsorption free energy of coal sample gas decreases gradually. The experimental results show that the gas adsorption process of coal body is a physical adsorption process of exothermic spontaneous and entropy decreasing.
【作者单位】：新疆维吾尔自治区煤炭科学研究所;西安科技大学教育部西部矿井开采及灾害防治重点实验室;西安科技大学安全科学与工程学院;
【分类号】：TD712

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