Characteristics of high temperature environment on coal pore structure and oxidation dynamics of Barapukuria coal mine in Bangladesh

doi:10.16265/j.cnki.issn1003-3033.2024.08.0061

Abstract

Abstract:

In order to prevent coal spontaneous combustion disasters under high-temperature environment and clarify the spontaneous combustion characteristics, coal samples from the 1306 working face of the VI coal seam in Barapukuria coal mine were selected. The coal samples were subjected to constant temperature treatment at 40, 50, and 60 ℃ for 30 days, and pore structure analysis and thermogravimetry(TG) were performed on the raw coal samples and high-temperature pretreated coal samples to test the oxidation kinetic parameters. The results show that after high-temperature treatment, the proportion of small pores decreases while the proportion of medium pores and large pores increases. After treatment at 60 ℃, the specific surface area of the coal sample increases from 2.351 m²/g of raw coal to 3.285 m²/g, and the total pore volume increases from 0.007 88 mL/g of raw coal to 0.010 01 mL/g. In addition, compared with raw coal, the ignition temperature and burnout temperature of the coal sample significantly decreased after high-temperature treatment, and the maximum weight loss and the maximum weight loss rate increased by 6.1% and 23.3%, respectively. The calculation results of oxidation kinetics show that the activation energy and pre-exponential factor of the coal sample after high-temperature treatment are lower than those of the raw coal, indicating that the high-temperature environment significantly improves the oxidation reaction activity and increases the risk of spontaneous combustion of coal.

Key words: high ground temperature, pore structure, oxidation dynamic characteristics, thermogravimetric (TG), coal spontaneous combustion

CLC Number:

X936

MA Dong, XIE Qingdian, ZHAO Zhiqiang, LIU Fang, ZHOU Qigeng. Characteristics of high temperature environment on coal pore structure and oxidation dynamics of Barapukuria coal mine in Bangladesh[J]. China Safety Science Journal, 2024, 34(8): 162-169.

Figures/Tables 10

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煤样	t₁	t₂	t₃	t₄	t₅	t₆	t₇
1306-原煤样	52.29	265.55	280.86	320.78	450.1	561.38	612.78
1306-40 ℃	52.29	259.54	275.67	316.68	436.71	529.67	581.07
1306-50 ℃	51.47	259.54	273.75	312.85	435.61	526.93	577.24
1306-60 ℃	51.46	250.24	267.46	311.21	429.87	463.23	573.41