Study of coal fire hazard by dynamic thermogravimetry

The results of thermogravimetric analysis of coal samples of grades Zh, GZh, and A are examined. The mass loss of the coal sample of grades Zh and GZh during thermogravimetric analysis is stepwise. The mass loss of the coal sample of grade A during thermogravimetric analysis is smooth and monotonic. For all studied coal grades Zh, GZh, and A, the primary mass loss of approximately 4% occurs at temperatures of approximately 350–370 ºС and is associated with the evaporation of external and hygroscopic moisture. The second mass loss for coal grades Zh and GZh occurs in two stages, ranging from approximately 350–660 ºС and 700–870 ºС. The first peak (479.95 ºС) is associated with endothermic processes, the second (772.32 ºС) with exothermic processes. In total, the two stages result in a mass loss of approximately 30%, with a loss of approximately 16% in the first stage and approximately 14% in the second stage. The second mass loss associated with the desorption of hydrocarbons is 1.6 times greater for GZh coal than for Zh coal, which corresponds to the ratio of volatile matter yield from these coal grades. The second mass loss for A coal is 2%, which is 8 to 13 times less than the mass loss for Zh and GZh coal. The third loss of mass of coal samples in the temperature range from 660 to 870ºC for coal grade Zh is 3.5 times greater than for coal grade GZh, which is explained by the ash content being 4.6 times higher for coal grade GZh compared to coal grade Zh. The smallest mass loss in the temperature range of 100 to 1200 ºC is observed in A-grade coals, amounting to 2%, which is 2 to 7 times less than in GZh- and Zh-grade coals. Of the studied coal samples, the GZh-grade coal sample is the most explosive and flammable.

Skopintseva O. V., Rybichev A. A., Balovtsev S. V. Study of coal fire hazard by dynamic thermogravimetry. MIAB. Mining Inf. Anal. Bull. 2026;(6):134-144. [In Russ]. DOI: 10.25018/0236_1493_2026_6_0_134.

O.V. Skopintseva¹, Dr. Sci. (Eng.), Professor, Professor, e-mail: skopintseva54@mail.ru, ORCID ID: 0000-0002-7257-8720, 
A.A. Rybichev¹, Assistant, e-mail: rybichev@yandex.ru, ORCID ID: 0009-0005-9269-201X,
S.V. Balovtsev¹, Dr. Sci. (Eng.), Assistant Professor, Professor, e-mail: balovcev@yandex.ru, ORCID ID: 0000-0002-0961-6050,
¹ NUST MISIS, 119049, Moscow, Russia.

A.A. Rybichev, e-mail: rybichev@yandex.ru.

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