Experimental study on thermal characteristics of coal samples with different metamorphism degree during spontaneous combustion

doi:10.16265/j.cnki.issn1003-3033.2021.10.009

Abstract

Abstract: To explore thermal characteristics of coal spontaneous combustion, different types and content of functional groups in coal samples were analyzed by FTIR. Then, parameters, such as weight loss and heat release, were analyzed based on multiple tests of TG-DSC, a kinetic equation was established and solved, and activation energy value E and pre-index factor A of samples were obtained. The results suggest that types of functional groups in coal molecules, in spite of their different metamorphism degrees, are similar. Content of hydroxyl group, aliphatic hydrocarbon and oxygen-containing functional groups in samples with low metamorphism is greater than that in those with high metamorphism, however, the latter's TG and DSC curves show deviation and hysteresis, its rate of coal oxygen recombination slows down, weight loss decreases and heat release increases. In the stage of weight gain, pre-index factor of coal with high metamorphism degree is the smallest, while in the stage of combustion, its activation energy and pre-index factor both increase, so more energy is needed for spontaneous combustion.

Key words: metamorphism degree, coal spontaneous combustion, thermal characteristics, fourier transform infrared (FTIR), activation energy, thermogravimetric-differential scanning calorimetry (TG-DSC)

CLC Number:

X936

JIA Tinggui, QIANG Qian, LOU Hezhuang, QU Guona. Experimental study on thermal characteristics of coal samples with different metamorphism degree during spontaneous combustion[J]. China Safety Science Journal, 2021, 31(10): 62-67.

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