TG-FTIR study on coal spontaneous combustion mechanism

doi:10.16265/j.cnki.issn1003-3033.2019.12.008

Abstract

Abstract: In order to study change features of coal molecular structure at occurrence and during development of its spontaneous combustion, with No. 15 coal in Fusheng Mine as an example, the spontaneous combustion mechanism of coal samples with medium sulfur content was analyzed. Firstly, TG-FTIR experiment was conducted to obtain characteristic temperature at different thermal weight loss stages and molecular structure and decomposition temperature of coals that reacted during corresponding stages. Then, analysis was made on distribution characteristics of functional groups of raw coal samples and variation in content of functional groups along with temperature change, and composition and content of functional groups of five coal molecular structures were obtained. The results show that critical reaction temperature range of Fusheng coal samples is 130-170 ℃ during low-temperature oxidation, and presence of sulfur in coal samples and oxidation of C-H and C-O / C-O-C bonds improve chemical activity of coal molecular structure, thus causing spontaneous combustion.

Key words: coal spontaneous combustion, coal oxygen reaction, low-temperature oxidation, thermogravimetric-Fourier transform infrared spectroscopy (TG-FTIR), coal molecular structure, functional group

CLC Number:

X932

ZHU Jianfang , SHEN Jiahui , SONG Fumei, DENG Huidong. TG-FTIR study on coal spontaneous combustion mechanism[J]. China Safety Science Journal, 2019, 29(12): 46-52.

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