Free radical reaction characteristics of coal low-temperature oxidation and its inhibition method

Springer Science and Business Media LLC - Tập 23 - Trang 23593-23605 - 2016
Zenghua Li1,2, Biao Kong1,2, Aizhu Wei3, Yongliang Yang2, Yinbo Zhou1,2, Lanzhun Zhang1,2
1Key Laboratory of Coal Methane and Fire Control, Ministry of Education, China University of Mining and Technology, Xuzhou, China
2School of Safety Engineering, China University of Mining and Technology, Xuzhou, China
3School of Chemical Engineering, Sichuan University, Chengdu, China

Tóm tắt

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.

Tài liệu tham khảo

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