不同热分析法解算煤自燃活化能的比较研究

Comparative Study on Activation Energy Calculation for Coal Spontaneous Combustion with Different Thermal Gravimetric Analysis Methods

为了准确计算煤自燃的活化能值,以作为科学划分煤自燃倾向性等级的判定指标,采用Coats-Redfern法、Flynn-Wall-Ozawa法、Kissinger法、Starink法、Fridman法等5种分析方法,分别对某矿区煤热分解反应过程的热分析数据进行处理,求解出相应的活化能,依次为37.788、30.222、23.511、24.237、27.288 k J/mol;进一步对各种方法的适用范围和优缺点进行了比较。研究结果表明:CoatsRedfern法需要对煤自燃的反应机理函数进行假设;Flynn-Wall-Ozawa法适用于E/RT13的条件,避开了因反应机理函数不同而引起的误差;Kissinger法只适用于反应机理函数为f(a)=(1-a)n的反应;Starink法的精确度比Kissinger法和Flynn-Wall-Ozawa法的精确度高。

In order to accurately calculate the activation energy value of coal spontaneous combustion and take it as thejudgment index for scientifically dividing the level of coal spontaneous combustion tendency, five analyzing methods includingCoats-Redfern method, Flynn-Wall-Ozawa method, Kissinger method, Starink method and Fridman method were applied torespectively process the thermal gravimetric analysis data in the course of the thermal decomposition and reaction of coal takenfrom a mining area, and corresponding activation energy values were solved; they were respectively 37.788, 30.222, 23.511,24. 237 and 27.288 kJ / mol; further comparison was carried out on the applicable scope, the advantages and disadvantages ofeach method. The research results showed that the Coats -Redfern method required to make an assumption for the reactionmechanism function of coal spontaneous combustion; the Flynn -Wall - Ozawa method was applicable to the condition withE/ RT〉13, and it avoided the errors caused by different reaction mechanism functions; the Kissinger method only suited for thereaction of the reaction mechanism function f（a）= （1-a）^ n; and the accuracy of the Starink method was higher than that of theKissinger and Flynn-Wall-Ozawa methods.