THERMAL SCIENCE

International Scientific Journal

Huailong Du

,

Kuiying Gao

,

Tao Jiang

,

Keqing Xue

,

Jianlei Guo

,

Qi Wang

PREPARATION AND SEALING PERFORMANCE OF INORGANIC SOLIDIFICATION MATERIAL WITH HIGH CONTENT OF COAL GANGUE IN GOAF

ABSTRACT
To address coal spontaneous combustion caused by air leakage in goafs and the limitations of traditional sealing materials, this study developed a high-dosage coal gangue inorganic solidification material (HDCG-ISM) using coal gangue and fly ash. The mix proportion was optimized via orthogonal experiments, and the sealing performance was evaluated using a self-designed apparatus. The optimal mix (85% coal gangue, 20% fly ash, 10% cement, 2% water reducer, 10% activator) achieved a 28-day compressive strength of 1.5 MPa with good stability. The material enhanced loose coal consolidation through physical filling, hydration product bonding, and interfacial chemical bonding. Compared to pure cement, its shrinkage rate was reduced by 21.95%, while specific surface area, pore volume, and average pore diameter decreased by 55.58%, 65.36%, and 22.02%, respectively. At 60 mm thickness, the material provided efficient sealing for 5-30 mm coal particles, reducing the sealing pressure difference by 38.5-66.7%. This study offers a new solution for coal-based solid waste utilization and goaf air leakage control.
KEYWORDS
coal spontaneous combustion, coal-based solid waste, Solidification mechanism, Sealing performance
PAPER SUBMITTED: 2026-03-09
PAPER REVISED: 2026-04-28
PAPER ACCEPTED: 2026-05-04
PUBLISHED ONLINE: 2026-08-07
DOI REFERENCE: https://doi.org/10.2298/TSCI260309155D
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Preparation and sealing performance of inorganic solidification material with high content of coal gangue in goaf

© 2026 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International licence