THERMAL SCIENCE

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Authors of this Paper

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Qiuling Zuo

,

Yujie Wang

,

Jingshan Li

STUDY ON THE OXIDATION AND HEATING CHARACTERISTICS OF RESIDUAL COAL IN GOAFS UNDER DIFFERENT AIR-LEAKAGE CONDITIONS

ABSTRACT
The spontaneous combustion of broken coal is one of the main causes for mine safety accidents in goafs. To determine the effect of different air-leakage conditions on the spontaneous combustion of leftover coal, the air-leakage passage of the goaf was designed based on the principle of Sudoku grid in an inflammable coal seam. The temperature rise during the auto-ignition oxidation of coal was studied using a self-built experimental platform. By changing the air-flow rate, the laws of the change in the oxygen consumption rate and the heat release intensity with the coal temperature were analyzed. Results show that the oxygen consumption rate had three obvious peaks at 48°C, 75°C, and 105°C, respectively. Above 80°C, spontaneously combustion of the experimental coal samples began. The exothermic intensity increased exponentially with the rise of temperature. Furthermore, an exponential relationship was observed between the air supply at the working face and the spontaneous combustion of broken coal in the goaf. In addition, the increase in air supply in the fully-mechanized mining face increased the width of the oxidation zone.
KEYWORDS
goaf, air-leakage conditions, oxidation characteristics
PAPER SUBMITTED: 2020-06-09
PAPER REVISED: 2020-08-29
PAPER ACCEPTED: 2020-09-22
PUBLISHED ONLINE: 2020-10-31
DOI REFERENCE: https://doi.org/10.2298/TSCI200609314Z
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2021, VOLUME 25, ISSUE Issue 5, PAGES [3293 - 3302]
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Study on the oxidation and heating characteristics of residual coal in goafs under different air-leakage conditions

© 2024 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-NonCommercial-NoDerivs 4.0 International licence