准确获得煤氧化自热过程中的反应动力学参数是研究煤自燃及其特性的基础。针对现有方法尚无法获得煤自燃不同反应温度对应的动力学参数这一问题，开展了煤氧化自热动力学参数测试方法的研究。基于热分析动力学理论推导得到了以转化率为纽带的煤氧化自热动力学参数计算模型，提出了多升温速率实验和恒温实验相结合的测试方法。为确定测试方法的最优参数，引入了煤氧化自热反应时间作为对比参量。采用绝热氧化测试装置和同步热分析仪开展了3种不同变质程度的干燥煤样在纯氧条件下的绝热氧化实验、多升温速率实验以及恒温实验。根据多升温速率实验结果，分析了升温速率对煤氧不同反应阶段整体质量变化量的影响，确定了煤氧化自热动力学参数测试的最大升温速率。在此升温速率范围内，依据推导的计算模型，对比分析了不同升温速率组合和转化率计算步长对动力学参数计算结果的影响，发现转化率计算步长主要影响动力学参数计算结果的疏密程度，而升温速率组合对动力学参数计算结果的影响不大。根据绝热氧化实验结果，综合考虑测试时间成本，确定了获得煤氧化自热动力学参数的最优实验和计算参数，并对其准确性和适用性进行了验证。结果表明:当升温速率组合为0.2，0.5，1.0，2.0 ℃/min，转化率计算步长为0.03时测试得到的煤氧化自热动力学参数与实际最为贴近。

It is the basis for studying coal spontaneous combustion and its characteristics to obtain the relationship between kinetic parameters and temperature in the process of coal selfheating oxidation,which can’t be obtained by existing methods.The research on the testing approach of kinetic parameters during coal selfheating oxidation had been carried out.Based on the theory of thermal kinetic analysis,the model for calculating the kinetic parameters of coal oxidation with extents of conversion as the bond was derived,and the testing approach combining multiple heating rate experiments and constant temperature experiments was proposed.In order to determine the optimal experimental and computational parameters of the testing approach,the reaction time of coal self heating oxidation was introduced.By-using thermal analyzer and adiabatic oxidation device,the adiabatic oxidation experiments,multiple heating rate experiments and constant temperature experiments of three different ranks of coal under the condition of pure oxygen were conducted.According to the multiple heating rate experiments results,the influence of heating rates on the global mass variation in different stage was analyzed respectively,and the maximum heating rate was determined.Within this range of heating rate and derived calculation model,the influence on kinetic parameters with different heating rates and extent of conversion step length was analyzed.It was found that the extent of conversion step length mainly affects the density of the kinetic parameters,while the combination of heating rates have little effect on the results of kinetic parameters.Based on the adiabatic oxidation experiment results and considered the time cost,the optimal experimental and computational parameters for obtaining the coal self heating oxidation kinetic parameters were determined,and their accuracy and applicability were verified.The results showed that when the heating rates are 0.2,0.5,1.0,2.0 ℃/min and the extent of conversion step length is 0.03,the self heating kinetic parameters of coal oxidation obtained from the experiment are closest to the reality.

1 理论基础

   1.1 动力学参数计算模型

   1.2 测试方法的提出

2 实验

   2.1 煤样选取与制备

   2.2 测试过程

3 实验结果分析

   3.1 升温速率对煤氧反应质量变化的影响

   3.2 升温速率组合和转化率计算步长对动力学参数的影响

   3.3 煤氧化自热温度与转化率对应关系

   3.4 最优升温速率组合和转化率计算步长的确定

   3.5 结果准确性与适用性验证

4 结论