Numerical research of heat and mass transfer during low-temperature ignition of a coal particle

Abstract

Numerical researches have been carried out to study the influence of air flow temperature and a fossil fuel particle rate on sufficient conditions of ignition in a "coal particle -air" system. Developed mathematical model takes into account interconnected processes of heat transfer in a coal particle and gas area, thermal decomposition of organic material, diffusion and gas-phase oxidation of volatiles, heating of a coke (carbon) and its heterogeneous ignition. The effect of low-temperature (about 600 K) ignition for a single coal particle is impossible even at variation of its rate (radius) from 0.05 mm to 0.5 mm. Nevertheless this process is possible for group of particles (two, three, et al.) situated at close-range from each other. The physical aspects of the problem are discussed.

Ignition of a coal particle at the low temperature of gas flow

“…When planning the experiment the following scheme of the investigated process was adopted [3]. The coal particle 11 was fixed on the axis of symmetry of the cylinder 7 (Fig.…”

Ignition of Coal Dust from the Tomsk Region Talovsky Deposit by Air Flow

“…The power plant will operate with a new type of fuel to generate heat and electricity. The development and implementation of design solutions require the full amount of information about the characteristics of physical and chemical processes occurring during coal ignition [5][6][7][8].…”

Change in Ignition Characteristics Of Composite Liquid Fuel Droplet While Varying the Combustible Liquid Content

“…In recent years, it was made efforts to use the coal-water suspensions as fuel at power engineering facilities [1,2] instead of traditional solid fuel [3,4]. This can be explained by several advantages of such compositions in comparison with coal dust: explosive safety, relatively low concentration of injurious substances (sulfur and nitrogen oxides) in gas-like combustion products, the possibility of utilization of solid and combustible waste.…”