To explore the effect of coalbed methane (CBM) airflow on coal oxidation under low temperatures, an experimental apparatus was developed and applied to simulate coal oxidation under different oxidizing atmospheres. The formation of carbon monoxide CO, the index gas, in CBM airflow was analyzed to obtain the optimum concentration of CH₄ that exerted the strongest influence on coal oxidation. Then, a comparison experiment was performed on coal oxidation in dry air and in CH₄ at the optimum concentration by using electron spin resonance (ESR) and Fourier transform infrared (FTIR) technology. The results suggest that 25% of CH₄ has the strongest effect on coal oxidation at low temperatures. The free radical concentration (N_g) in coal increases with temperature in both dry air and 25% CH₄. At this concentration, CH₄ can inhibit the reactivity of coal substantially while raising the excitation temperature. The oxidation of aliphatic hydrocarbons is severely inhibited by 25% CH₄, which reduces its consumption rate and abates its decrement in the initial phase. Although 25% CH₄ restricts the consumption of –OH and –COOH in oxidation, it promotes the formation of –C–O.

中文翻译：

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最佳作用浓度煤层气气流对低温下煤氧化的影响

为了探索低温下煤层气（CBM）气流对煤氧化的影响，开发了一种实验装置并将其应用于模拟不同氧化气氛下的煤氧化。分析了煤层气气流中一氧化碳CO（指示气）的形成，以获得对煤氧化影响最大的最佳CH ₄浓度。然后，使用电子自旋共振（ESR）和傅里叶变换红外（FTIR）技术对最佳浓度的干燥空气和CH ₄中的煤氧化进行了对比实验。结果表明，低温下25％的CH ₄对煤的氧化作用最强。自由基浓度（N _g在干燥空气和25％CH _4中，煤中的γ随温度升高而增加。在该浓度下，CH ₄可以在提高激发温度的同时充分抑制煤的反应性。25％CH ₄会严重抑制脂肪烃的氧化，这会降低其消耗速率并减少其初始阶段的减量。尽管25％CH ₄限制了氧化过程中–OH和–COOH的消耗，但它会促进–C–O的形成。