Influence of the Properties of Fossil Coal on Its Tendency to Self-Ignition
P. N. KUZNETSOV1, A. S. MALOLETNEV2, Z. R. ISMAGILOV3,4
1Institute of Chemistry and Chemical Technology, Siberian Branch of the Russian Academy of Sciences, Akademgorodok 50, Build. 24, Krasnoyarsk 660036
2Moscow Institute of Mines, Leninsky Prospekt 6, Moscow 119991
3Institute of Coal Chemistry and Material Science, Federal Research Centre of Coal and Coal Chemistry, Siberian Branch of the Russian Academy of Sciences, Sovetskiy Pr. 18, Kemerovo 650000
4Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences, Prospekt Akademika Lavrentyeva 5, Novosibirsk 630090
Keywords: самовозгорание углей, окисление, состав, структура, coal self-ignition, oxidation, composition, structure
Abstract
Russian and foreign works describing coal self-ignition during mining, during storage in stores, dumps of coal mines and open pits are generalized. The features of these processes are analyzed depending on metamorphism stages, petrographic composition, and porous structure of coal, water content and concentrations of mineral components. It was noted that self-ignition processes include mainly the oxidation of aliphatic structures containing oxygenated functional groups, branched aliphatic chains, methylene groups connected with aromatic rings. The highest tendency to self-ignition is exhibited by brown and black coal of low metamorphism degree. A definite effect on the tendency to self-ignition may be due to mineral substances present in coal. Fine porous structure of the organic mass defines mainly diffusion-kinetic regime of oxidation reactions. As a rule, the effect of diffusion stages is less essential in comparison with the effect of metamorphism degree and humidity of coal. It was noted that self-ignition of coal is due to the combined action of a large number of factors of different nature, including chemical, physical, mining and geological conditions. Their effects are manifested to different extents and are studied insufficiently. To establish physicochemical foundations of the reactions of coal with oxygen, reveal key stages of self-heating and ignition, elaborate reliable criteria for prediction, new data relying on thorough interdisciplinary studies involving modern chemical and physical methods are necessary. Taking into account the multifactor nature of self-ignition phenomena, endogenous fire events and explosions, it is reasonable to elaborate the criteria for coal and beds under specific mining and geological conditions similarly to the basin-related industrial classification of coal.
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