武乡矿区多煤种低温氧化阶段特性参数研究

Research on Characteristic Parameters of Low Coal Oxidation Stage of Multiple Coal Types in Wuxiang Mining Area

针对数值模拟过程中因煤自然发火导致瓦斯爆炸所需的重要基础数据不足,在试验室借助热重试验研究不同煤种质量和放热量的变化规律,得到不同煤样发生低温氧化时的温度区域。通过管式炉程序升温和色谱仪开展不同煤样产生气体分析试验,确定在不同温度时管式炉出口不同气体的含量,得到耗氧速率、CO与CO2生成速率、放热强度与温度变化规律。试验结果证明:着火温度与煤的变质程度呈正比关系,煤的变质程度越高,发生低温氧化时温度区域越宽;温度相同时,煤的耗氧速率、CO与CO2生成速率、放热强度与变质程度呈反比,变质程度较差的煤,更加容易发生自燃;CO产生速度高于CO2产生速度;随着温度的升高,耗氧速率、CO与CO2生成速率、放热强度指数关系升高;放热强度与耗氧速率呈线性关系。试验结果可用于煤发生自燃时的数值模拟和预测火区发生瓦斯爆炸危险性。

Aiming at the lack of important basic data required for gas explosion caused by natural coal ignition during the numerical simulation process, the thermogravimetric test was used in the laboratory to study the changes in the quality and heat release of different coal types, and the results of low-temperature oxidation of different coal samples temperature zone. Analyze the gas produced by different coal samples through the tube furnace program heating and chromatograph, determine the content of different gases at the tube furnace outlet at different temperatures, and get the oxygen consumption rate,CO and CO2 generation rate, exothermic intensity and temperature changes.. The test results show that the ignition temperature is directly proportional to the degree of coal deterioration. The higher the degree of coal deterioration, the wider the temperature range when low-temperature oxidation occurs;when the temperature is the same, the oxygen consumption rate, CO and CO2 generation rate, and exothermic strength of the coal Inversely proportional to the degree of metamorphism, coal with poor metamorphism is more prone to spontaneous combustion;the rate of CO production is higher than the rate of CO2 production;as the temperature increases, the relationship between the rate of oxygen consumption, the rate of CO and CO2 production, and the index of heat release increases High;exothermic intensity is linearly related to the rate of oxygen consumption. The test results can be used for numerical simulation of coal spontaneous combustion and prediction of the danger of gas explosion in the fire zone.