不同变质程度煤燃烧特性及动力学参数研究

发布时间：2018-08-30 07:51

【摘要】：为研究煤的变质程度对煤矿火灾时期煤燃烧放热特性的影响,选取6种不同变质程度煤样作为试验样品,采用STA-449C型同步热分析仪进行热重(TG)试验。研究煤样的质量变化、放热量变化规律。通过对TG曲线进行一阶微分得到煤样失重速率(DTG)曲线。利用Freeman-Carrol模型计算各煤样的燃烧反应动力学参数。结果表明:失重率和最大失重速率随着煤样变质程度升高逐渐降低,DTG曲线近似符合Gauss分布;初始放热温度T_(f_0)随着煤样水分含量升高而升高;煤样变质程度升高,特征温度点T_1,T_3,T_(s_1)与T_4呈线性增加,T_(f_0)与T_(s_0)呈线性下降趋势变化;放热量随煤变质程度升高呈指数关系变化,相同温度时,煤样变质程度越高放热量越小;煤化程度越高,综合燃烧特性指数S越大,放热量越大,失水活化能、着火活化能与燃烧活化能均升高。
[Abstract]:In order to study the influence of coal metamorphism degree on coal combustion exothermic characteristics during coal fire, six kinds of coal samples with different metamorphism degrees were selected as test samples and thermogravimetric (TG) test was carried out with STA-449C synchronous thermal analyzer. The changes of coal quality and heat release were studied. The (DTG) curve of coal sample weightlessness rate was obtained by first order differentiation of TG curve. The kinetic parameters of combustion reaction of coal samples were calculated by Freeman-Carrol model. The results show that the weight loss rate and the maximum weight loss rate decrease gradually with the increase of the metamorphism degree of coal samples, and the initial exothermic temperature T _ (f _ 0) increases with the increase of moisture content of coal samples, and the metamorphism degree of coal samples increases. The characteristic temperature point T _ 1 / T _ 3 T _ (s _ S _ 1) and T _ 4 showed a linear increasing trend of decreasing trend of T _ (f _ 0) and T _ (s _ 0). The heat release changed exponentially with the increase of coal metamorphism. At the same temperature, the higher the metamorphic degree of coal, the smaller the heat release, and the higher the degree of coalification, the higher the degree of coalification. The larger the comprehensive combustion characteristic index S, the greater the heat release, the higher the activation energy of water loss, the higher the ignition activation energy and the combustion activation energy.
【作者单位】：辽宁工程技术大学安全科学与工程学院;矿山热动力灾害与防治教育部重点实验室;
【基金】：国家自然科学基金资助(51274115)
【分类号】：TD75;TQ534

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