Zhang Shanxue, Wang Zhaofeng, Fan Daopeng, Qiu Yang, Chen Yanqi
School of Safety Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, Henan, China.
State Key Laboratory Cultivation Base for Gas Geology and Gas Control, Henan Polytechnic University, Jiaozuo 454000, Henan, China.
ACS Omega. 2024 Sep 13;9(38):39986-39996. doi: 10.1021/acsomega.4c05816. eCollection 2024 Sep 24.
The coal is affected by the latent heat of the phase change of in situ and migrating water and the exothermic heat of gas adsorbed by the coal during the freezing process, which leads to different temperatures at different locations and times inside the coal. Relying on the independently developed simulation platform for the freezing response characteristics of gas-containing coal, simulation experiments on the internal temperature change of the coal freezing process under different ambient cryogenic treatment temperatures were carried out, and the effects of the phase change latent heat of the in situ water and migrating water and the exothermic heat of gas adsorbed by the coal on the freezing coal temperature field were taken into account, so as to establish a temperature field model of the cryogenic treatment process of the coal under the influence of the thermal effect of the water and gas and construct the internal heat transfer model of the freezing coal with the aid of COMSOL. The internal heat transfer of frozen coal was constructed with the help of COMSOL, and the mathematical model of temperature field proposed in this paper was simulated and verified. The results show that the change in temperature with time in the coal cryogenic treatment process is consistent with the experimental law. It is generally divided into four stages: rapid decline, short stabilization, slow decline, and relative stability, and the maximum error between the simulation temperature and the experimentally measured temperature is 0.85 K. The rate of temperature decrease of coal during the cryogenic treatment process is accelerated with the decrease of ambient freezing temperature, and the duration of short stabilization of temperature is shortened in the stage of water phase change. The mathematical model proposed in this article can be used to simulate and characterize the temperature field distribution and changes during the cryogenic treatment process of water-containing gas-containing coal.
在冻结过程中，煤受到原地水和迁移水的相变潜热以及煤吸附气体的放热影响，导致煤内部不同位置和不同时间的温度不同。依托自主研发的含瓦斯煤冻结响应特性模拟平台，开展了不同环境低温处理温度下煤冻结过程内部温度变化的模拟实验，考虑了原地水和迁移水的相变潜热以及煤吸附气体的放热对冻结煤温度场的影响，从而建立了水热效应影响下煤低温处理过程的温度场模型，并借助COMSOL构建了冻结煤内部传热模型。借助COMSOL构建了冻结煤内部传热过程，对本文提出的温度场数学模型进行了模拟验证。结果表明，煤低温处理过程中温度随时间的变化规律与实验规律一致。一般分为快速下降、短暂稳定、缓慢下降和相对稳定四个阶段，模拟温度与实测温度的最大误差为0.85K。低温处理过程中煤的降温速率随着环境冻结温度的降低而加快，在水相变阶段温度短暂稳定的持续时间缩短。本文提出的数学模型可用于模拟和表征含瓦斯含水煤低温处理过程中的温度场分布及变化。
