煤的绝热氧化阶段特征及自燃临界点预测模型

Prediction model of coal spontaneous combustion critical point and the characteristics of adiabatic oxidation phase

为建立煤的绝热氧化阶段特征和自燃临界点的预测模型,基于绝热氧化实验、元素分析实验以及工业分析实验,首先得到了8个煤样的绝热氧化实验数据,据此计算出煤的绝热氧化阶段升温速率;然后运用热动力参数计算方法,定义并获取了各煤样的自燃临界点Tr0.05和TΔmax;最后应用Levenberg-Marquardt法计算拟合得出了煤元素含量、挥发分与绝热氧化阶段升温速率、Tr0.05的关系。结果表明:N,S元素含量与Tr0.05呈正相关,O,C,H元素含量与Tr0.05呈负相关,而各元素与阶段升温速率关系恰好相反;上述规律也表明Tr0.05越低,阶段升温速率越快,则煤越易自燃;煤的挥发分越大,煤的Tr0.05越低,煤越易自燃。

To investigate the characteristics of adiabatic oxidation phase and build the prediction model of coal sponta- neous combustion critical point, the adiabatic oxidation experiment data of eight coal samples are given in this paper, based on the adiabatic oxidation experiment, element analysis experiment and industrial analysis experiment. The phase heating rates of adiabatic oxidation of these samples are also calculated. Then using the thermodynamic parameter calculation method, T0. 05 and TAmax are defined and obtained. Furthermore, based on the Levenberg-Marquardt method, the relationship between the coal element content, volatility, the phase heating rate of adiabatic oxidation and Tr0.05 are established. The results show that the content of N or S correlates positively with Tr0.05 and that O, C, or H content corre- lates negatively with To. 05- However, the link between these elements and stage-heating rate is the opposite. The law al- so suggests that stage-heating rate will be much faster and coal spontaneous combustion will be easier when Tr0. 05 becomes much lower. The more volatile coal is, the lower Tr0. 05, and the more likely it is to spontaneously combust.