Key Laboratory of Coal Methane and Fire Control, Ministry of Education, China University of Mining and Technology, Xuzhou, Jiangsu, 221116, China.
School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, 221116, China.
Environ Sci Pollut Res Int. 2016 Dec;23(23):23593-23605. doi: 10.1007/s11356-016-7589-x. Epub 2016 Sep 10.
Study on the mechanism of coal spontaneous combustion is significant for controlling fire disasters due to coal spontaneous combustion. The free radical reactions can explain the chemical process of coal at low-temperature oxidation. Electron spin resonance (ESR) spectroscopy was used to measure the change rules of the different sorts and different granularity of coal directly; ESR spectroscopy chart of free radicals following the changes of temperatures was compared by the coal samples applying air and blowing nitrogen, original coal samples, dry coal samples, and demineralized coal samples. The fragmentation process was the key factor of producing and initiating free radical reactions. Oxygen, moisture, and mineral accelerated the free radical reactions. Combination of the free radical reaction mechanism, the mechanical fragmentation leaded to the elevated CO concentration, fracturing of coal pillar was more prone to spontaneous combustion, and spontaneous combustion in goaf accounted for a large proportion of the fire in the mine were explained. The method of added diphenylamine can inhibit the self-oxidation of coal effectively, the action mechanism of diphenylamine was analyzed by free radical chain reaction, and this research can offer new method for the development of new flame retardant.
煤自燃机理的研究对控制煤自燃火灾具有重要意义。自由基反应可以解释煤在低温氧化过程中的化学过程。电子自旋共振（ESR）光谱用于直接测量不同种类和不同粒度的煤的变化规律；通过对空气和吹氮气、原煤样、干煤样和脱矿煤样的煤样进行比较，得出了随温度变化的自由基 ESR 图谱。碎裂过程是产生和引发自由基反应的关键因素。氧气、水分和矿物质加速了自由基反应。自由基反应机制与机械碎裂相结合，导致 CO 浓度升高，煤柱断裂更容易自燃，采空区自燃占矿山火灾的很大比例，这一机制解释了这一现象。添加二苯胺的方法可以有效地抑制煤的自氧化，通过自由基链式反应分析了二苯胺的作用机制，为开发新型阻燃剂提供了新的方法。
