风化煤自燃性程序升温氧化实验研究

摘要

为研究风化煤的自燃特性,运用程序升温实验台,对弱粘煤、1/3焦煤进行程序升温,之后通入N2 进行绝氧降温,以此作为风化煤进行二次程序升温,通过测定原煤和风化煤程序升温过程中的O2 浓度,计算不同阶段的反应活化能和指前因子,研究风化煤自燃特性变化规律. 实验结果表明:在临界温度以前,弱粘煤的原煤反应活化能和指前因子低于1/3焦煤,超过临界温度,则高于1/3焦煤;风化煤的反应活化能和指前因子在干裂温度以前明显低于原煤,超过干裂温度,弱粘煤的风化煤反应活化能和指前因子低于原煤,并逐渐接近原煤,1/3焦煤的风化煤反应活化能和指前因子超过原煤;原煤和风化煤的反应活化能及指前因子随温度升高均呈增大趋势.%In order to study the spontaneous combustion characteristics of the weathered coal, the temperature programmed experiments of weakly caking coal and 1/3 coking coal were carried out with the temperature programmed experiment table, and then the anaerobic cooling treatment of these coals was conducted by injecting N2 , this was regarded as the secondary temperature programmed of the weathered coal. By measuring O2 concentration in the process of the temperature programmed of the raw coal and weathered coal, the reaction activation energy and preexponential factor at different stages were calculated, and the variation regularity of spontaneous combustion characteristics of the weathered coal was studied. The experiment results showed that the reaction activation energy and pre-exponential factor of the weakly caking coal were lower than that of 1/3 coking coal when the temperature was below the critical temperature; the reaction activation energy and pre-exponential factor of the weakly caking coal were higher than that of 1/3 coking coal when the temperature was over the critical temperature;the reaction activation energy and pre-exponential factor of the weathered coal were clearly lower than that of the raw coal when temperature was below the dry temperature, and when the temperature was over the dry temperature, the reaction activation energy and pre-exponential factor of the weathered coal of the weakly caking coal were lower than that of the raw coal, and the reaction activation energy and pre-exponential factor of weathered coal of 1/3 coking coal were higher than that of the raw coal;the reaction activation energy and pre-exponential factor of both raw coal and weathered coal tended to increase with the temperature rise.