煤体自然发火判识模型

Coal Spontaneous Ignition Identification Model

本文采用室内试验和现场试验结合,提出白胶煤矿煤体自然发火判识模型,对不同粒度煤样进行升温实验表明,CO在常温下既有,C2H6在50℃开始出现,C2H4在125℃开始出现,C2H2在50℃开始出现,C2H6在50℃开始出现,C2H2在试验温度范围内未出现;CO浓度随温度升高基本呈指数规律增加,温度大于120℃时变化趋势明显。CH4浓度在130℃~150℃时达到最大值,随后逐步下降。实验初始阶段没有C2H6和C2H4气体,在50℃左右温度下才出现少量的C2H6气体。CO2在整个实验阶段存在高温脱附现象,在110℃~120℃左右CO2脱附量最大,在140℃左右脱附基本完成;随着温度的升高,C2H4/C2H6、CH4/C2H6值逐渐增大;随着温度升高CO2/CO值明显增加,到38℃达到峰值。随着温度继续升高,CO2/CO值呈下降趋势,到120℃左右达到谷值。根据煤体自然升温过程实验室测试结果和现场实践经验,CO和C2H4/C2H6作为判识煤体自然发火的指标气体,其中以CO为主,C2H4/C2H6为辅。

Based on the combination of laboratory test and field test, this paper puts forward a model of spon-taneous combustion of coal in white rubber coal mine. The heating experiment of different size coal samples showed that CO appeared at normal temperature, C2H6 began to appear at 50?C, C2H4 began to appear at 125?C, C2H2 appeared at 50?C, C2H6 began to appear at 50?C, and C2H2 did not appear in the range of experimental temperature. The concentration of CO increased exponentially with the increase of temperature, and the change trend was obvious when the temperature was greater than 120?C. The concentration of CH4 reached the maximum at 130?C - 150?C, and then decreased gradually. The concentration of CH4 reached the maximum at 130?C - 150?C, and then decreased gradually. At the initial stage of experiment, there was no C2H6 and C2H4 gas, and only a small amount of C2H6 gas appeared at 50?C or so. CO2 has high temperature desorption phenomenon at the whole experimental stage. The desorption amount of CO2 is the largest at about 110?C - 120?C, and the desorption is basically completed at about 140?C. With the increase of temperature, the value of C2H4/C2H6 and CH4/C2H6 increases gradually, and the value of CO2/CO increases with the increase of temperature, and reaches the peak at 38?C. As the temperature continues to rise, the CO2/CO value decreases and reaches the valley value at about 12?C degrees. According to the laboratory test results and practical experience of coal body natural heating process, CO and C2H4/C2H6 are used as indicators to identify the natural ignition of coal, with CO as the main and C2H4/C2H6 as the supplement.