A novel understanding of combustion behavior of coals by cone calorimeter

Abstract

Coal has played a significant role in daily life. However, the highly effective combustion and reducing combustion-caused hazards of the coal still hold a great challenge. In this work, effect of particle size on combustion behaviors of two kinds of coals, i.e., Tashan weakly caking coal (TS) and Ningxia coking coal (NX), was studied by the cone calorimeter. The results obtained from cone calorimeter testing indicated that the time to ignition and the values of peak of heat release rate of TS and NX coal samples increased with increasing their particle size. TS coal samples showed an increased content of char residues with the increment in the particle size, whereas the char residues of NX were decreased with the increase in the particle size. The total smoke production values of the TS coal samples were increased as the particle size increased, whereas NX coal samples presented an opposite trend in the total smoke production. This phenomenon is caused by the difference in density of char residues during the combustion process of the coal samples. With regard to the volatile gaseous release, it was noted that the highest total carbon monoxide yield of TS was higher than that of NX. In addition, the total carbon dioxide yields of TS and NX coal samples were decreased with the increase in the particle size. This work paves a potential pathway to explore highly effective burning model of coal.