煤体自然发火判识模型

Coal Spontaneous Ignition Identification Model

摘要: 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。

Abstract: 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.