为研究不同氧气体积分数对含硫煤低温氧化自燃的影响，选取山西石港煤业有限责任公司14号和15号煤层煤样作为试验样品,开展不同氧气体积分数下管式炉程序升温试验。14号和15号煤样的氧气体积分数分别为21.0%和21.0%、12.2%和12.1%、10.2%和10.1%、7.1%和7.2%、5.0%和5.1%、2.9%和2.8%,共6个组别,并联用气相色谱仪分析气体成分。研究了不同氧气体积分数下14号煤样与15号煤样在低温氧化阶段CO气体与特征温度变化规律。通过计算不同氧气体积分数、不同温度时刻的耗氧速率和放热强度,分析了耗氧速率、放热强度与温度之间的对应关系，并对氧气体积分数为21%时14号煤样与15号煤样耗氧速率和放热强度进行拟合。计算出不同氧气体积分数下14号煤样与15号煤样低温氧化表观活化能，分析了氧气体积分数与表观活化能之间的关系，根据煤自燃临界温度及表观活化能变化特性得出了14号煤样与15号煤样的自燃临界氧气体积分数值。结果表明：在试验测试范围内(氧气体积分数2.8%～21.0%,温度30～300 ℃),提高氧气体积分数有助于14号煤样与15号煤样氧化发展,降低氧气体积分数则抑制其发展，14号煤样的自燃倾向性大于15号煤样，14号和15号煤层自燃临界氧气体积分数分别为5.0%和7.2%；氧气体积分数恒定时，CO释放量、耗氧速率及放热强度均随温度升高而增大，符合指数函数变化规律，同一组别的14号煤样各温度点的CO释放量、耗氧速率及放热强度均大于15号煤样，表观活化能和自燃临界温度则小于15号煤样；温度恒定时，随着氧气体积分数的降低，CO释放量、耗氧速率及放热强度减小，表观活化能和自燃临界温度增大；耗氧速率、放热强度随温度变化的拟合曲线及自燃临界氧气体积分数值可为采空区煤自燃特性数值模拟及自燃危险区域划分提供重要参量。

In order to study the influence of different oxygen concentrations on low-temperature oxidation and spontaneous combustion of sulfur-containing coal, coal samples of No. 14 and No. 15 coal seams of Shanxi Shigang Coal Industry Co., Ltd. were selected as test samples to carry out temperature-programming experiments of tube furnaces under different oxygen concentrations. There are 6 groups in total, the oxygen concentrations of No. 14 and No. 15 coal samples are 21.0% and 21.0%, 12.2% and 12.1%, 10.2% and 10.1%, 7.1% and 7.2%, 5.0% and 5.1%, 2.9% and 2.8%, respectively. And the gas composition was analyzed by parallel gas chromatograph. By calculating the oxygen consumption rate and heat release intensity at different oxygen concentrations and temperatures, the corresponding relationship between the oxygen consumption rate, heat release intensity and temperature was analyzed, and the oxygen consumption rate and heat release intensity of No. 14 coal sample and No. 15 coal sample were fitted when the oxygen concentration was 21%. The apparent activation energy of low temperature oxidation of No. 14 and No. 15 coal samples under different oxygen concentrations was calculated, the relationship between oxygen concentration and apparent activation energy was analyzed. According to the critical temperature of spontaneous combustion oxidation and the change characteristics of apparent activation energy, the critical oxygen concentration of No. 14 and No. 15 coal samples was obtained. In the test range(oxygen concentration 2.8%−21%, temperature 30−300 ℃), the results show that increasing the oxygen concentration is helpful for the oxidation development of No. 14 and No. 15 coal samples, while reducing the oxygen concentration will inhibit its development. The spontaneous combustion tendency of No. 14 coal sample is greater than that of No. 15 coal sample, and the critical oxygen concentration of spontaneous combustion of No. 14 and No. 15 coal seams is 5.0% and 7.2% respectively. When the oxygen concentration is constant, the CO release volume, oxygen consumption rate and heat release intensity all increase with the increase in temperature, which conforms to the exponential function. The CO release volume, oxygen consumption rate and heat release intensity of No. 14 coal sample at each temperature point of the same group are larger than that of No. 15 coal sample, while the apparent activation energy and critical temperature of spontaneous combustion are smaller than that of No. 15 coal sample. When the temperature is constant, the CO release, oxygen consumption rate and heat release intensity decrease with the decrease of oxygen concentration, while the apparent activation energy and critical temperature of spontaneous combustion increase. The fitting curve of oxygen consumption rate and heat release intensity with temperature and the critical oxygen concentration value of spontaneous combustion can provide important parameters for numerical simulation of spontaneous combustion characteristics of coal in goaf and classification of spontaneous combustion risk area.