煤自燃阶段动力学参数及特征温度点的实验研究

Experimental study of stage characteristic parameters and temperature on coal spontaneous combustion

为了考察程序升温实验条件下煤自燃阶段特征参数的变化情况,分别对常村贫煤、兴县气肥煤、唐山1/3焦煤等煤样的进行程序升温实验,得到3煤样在低温自燃阶段其指标气体的析出变化曲线。实验结果表明:在同一受热温度,低变质程度的气肥煤其CO,C2H4等指标气体的析出浓度比高变质程度的焦煤和贫煤高,而C2H6则相反;CO特征气体在受热初期并不是所有煤样都存在,且C2H4,C2H6的释放规律与煤质无关;通过对低温段内煤自燃的反应能级及活化能值的计算,得到煤低温氧化段内的反应能级及活化能值,并找出了阶段特征温度点。煤反应能级和活化能的大小反映了煤在不同温度段内其自身氧化能力的强弱,特征温度点温度则可用来判断煤自燃所处的燃烧阶段。

In order to investigate the changes on the stage characteristic parameters of coal spontaneous combustion under the condition of temperature programmed experiment, the Changcun lean coal, Xingx- ian gas-fat coal, and Tangshan 1/3 coke coal are tested, characteristic gas curves are got for 3 coal sam- ples in the low temperature combustion phase. The results show that ： at the same heating temperatures, the concentration of the index gas such as CO, C2 H4 on the gas-fat coal of low metamorphic is higher than coking coal and lean coal in the high metamorphic, and the C2 H6 is opposite. CO is occurred at the beginning of the heat not for all samples, and C2 H4 and C2 H6 release has nothing to do with the meta- morphic degree. Calculated the reaction level and activation energy values of coal spontaneous combus- tion in the low temperature, the reaction energy level and energy values are gained, and the phase char- acteristics of the temperature is found. The size of the coal reaction level can directly reflect the coal＇ s oxidation ability which is strong or weak at the different temperature periods. The characteristic tempera- ture point can be used to judge the phase in the combustion.