Influence of an Oxidant on the Ignition of Coals

Abstract—Possible chemical reaction schemes of the interaction of the organic matter of coal (OMC) with the decomposition products of sodium nitrite in the determination of the ignition temperatures of unoxidized (reduced), tested, and oxidized coals according to DSTU 7611:2014 “Coal: Method for the Determination of Oxidation and the Degree of Oxidation” were proposed. Studies on the determination of the ignition temperatures of 170 samples of unoxidized coals of various types from Ukraine, the Russian Federation, Canada, Australia, the Czech Republic, Poland, and Indonesia were carried out to evaluate the influence of the composition, structure, and properties of these coals on the ignition temperature. Close correlations of the ignition temperatures of unoxidized coals with the concentrations of organic (C^daf) and aromatic (C_ar) carbon in them, the structural parameter δ characterizing the degree of unsaturation of the OMC structure, the vitrinite reflectance (R₀), and the yield of volatiles (V^daf) were established.