Effect of Coal Dust Content on the Low-temperature Oxidation of Silo Coal

Abstract

Coal's low-temperature oxidation (LTO) poses a significant threat to the safety of storing coal in silos. This study investigates the impact of coal dust content on the LTO characteristics of silo coal samples. The results indicate that the larger the coal dust content the higher the oxygen (O 2 ) consumption rate and carbon monoxide (CO) generation rate and the stronger the LTO capacity. To clear the mechanism of the impact, the thermal physical characteristics were studied and thermogravimetric and differential thermal analysis (TG-DTA) experiments were performed on various coal samples. The results show that, first, with the increase of coal dust content, the thermal conductivity of the silo coal samples initially increased and then decreased, whereas the thermal diffusion and heat capacity decreased and increased linearly, respectively. This indicates that the heat storage capacity of the silo coal sample is enhanced with the increase of the coal dust content. Second, the maximum oxygen absorption rate and differential thermal reduction value of the coal samples increased linearly with the decrease in their particle size; this result verifies that decreasing the particle size of silo coal can advance its LTO process. The study findings indicate that the risk of LTO and spontaneous combustion of silo coal can be effectively reduced by controlling the coal dust content (fine coal particles).

Suppression Characteristics and Mechanism of Molasses Solution on Coal Dust: A Low-Cost and Environment-Friendly Suppression Method in Coal Mines

“…To analyze the suppression efficiency of molasses solution on the test samples, the ∆m reduction percentage (P) of the molasses solution over that of pure water (0% molasses) was computed using Equation (5).…”

“…The rapid development of science and technology has become synonymous with improved living standards for many parts of the world, and these improved living standards have been accompanied by an increase in energy demand [ 1 , 2 , 3 ]. With regard to energy, coal is one of the most widely used energy sources, and this is especially true in developing countries, where coal is the primary source of energy [ 4 , 5 ]. To meet the ever-increasing demands, the mining intensity of coal is increasing yearly, resulting in severe coal dust pollution in underground coal mines [ 6 , 7 ].…”

Design and Optimization of a Novel Dust Collection Device for Underground Dry Drilling Based on Numerical Simulation and Field Testing

“…In the drilling process, a large amount of dust is ejected from the drill hole under the action of the wind jet of the drill head [10]. Then, the dust spreads to the tunnels and causes pollution, posing a severe threat to the health and safety of the workers [11,12] and possibly even triggering coal dust explosions that result in injuries and casualties [13][14][15]. To control the dust generated by underground dry drilling, drill hole dust collection devices are now commonly used for sealing in synergy with a secondary dust removal device [16,17].…”