Experimental study on inhibition of coal spontaneous combustion by carbon dioxide and nitrogen

作者：Linxiao Yan, Yueping Qin, Changqing Chu, Biao Sun, Yi Xu, Qiaohong Jiang, Yipeng Song, Fei Tang, Hao Xu · 发表于：Energy Sources Part A Recovery Utilization and Environmental Effects · 年份：2024 · DOI：10.1080/15567036.2024.2348097 · 被引用次数：14 · 研究领域：Coal Properties and Utilization、Combustion and Detonation Processes、Safety and Risk Management

Injecting CO2 and N2 to reduce the concentration of O2 in the air is a commonly used measure to prevent coal spontaneous combustion (CSC). To study the difference in inhibitory effects of CO2 and N2 on coal oxidation, experiments in this study were conducted using a setup of self-developed gas-bath coal oxidation for low temperatures. The oxidation process of the coal-oxygen system was then analyzed using reaction kinetics. Two different coal samples were tested in experiments under two inert gas environments, i.e. CO2 and N2 with various O2 concentrations, respectively. The changes in O2 and CO concentrations were measured during the oxidation process. By studying the standard oxygen consumption rate (SOCR) and the apparent activation energy of the coal-oxygen reaction system, inhibitory effects of CO2 and N2 on CSC were analyzed and compared. The results showed that the SOCR of the same coal sample remained consistent and independent of the O2 concentration within the same inert gas environment although under different O2 levels. In both CO2-O2 and N2-O2 environments, the SOCR of the coal sample exhibits exponential growth with temperature. The SOCR was found to have a functional connection with temperature, it can be represented as y=a⋅ebT, and the R2 (determination coefficients) of the fitting formulas are all greater than 0.94. In the correlation, the inert gas environment has minimal impact on coefficient “b,” while in the CO2-O2 environment, reducing the value of coeff...