Institute of Integrated Mineral Development – IPKON, Russian Academy of Sciences, Moscow, Russia:

O. N. Malinnikova, Head of Laboratory, Doctor of Engineering Sciences, olga_malinnikova@mail.ru
E. V. Ulyanova, Leading Researcher, Doctor of Engineering Sciences, ekaterina-ulyanova@yandex.ru
M. O. Dolgova, Leading Engineer
I. V. Zverev, Leading Engineer

The review of the statistics on outbursts in mines in the coal basins of Donetsk, Kuznetsk, Vorkuta, Pechora and Karaganda as well as at Egorhsin deposit shows that the specific gas release (ratio of released gas to outburst coal) is many times, occasionally by an order of magnitude, higher than gas content of coal beds. The statistical treatment of the data by the linear regression method yields that the released gas amount is proportional to the outburst coal amount rather than to the outburst cavity surface area in all samplings. Put it otherwise, it is confirmable that outburst gas releases from outburst coal rather than from outburst cavity. The petrographic analysis of coal sampled from bed l3 in Krasny Liman Mine shows that an outbursthazardous zone contains considerably more aliphatic fringe than an outburst-nonhazardous zone. After the application of IR and 13C-NMR spectroscopy of coal, it has been concluded that coal undergoes intramolecular failure during an outburst, with breakage of the weakest bonds in the fringe, and many methyl groups get lost in addition; moreover, it has been found that IR and 13C-NMR spectroscopy enable finding connection between the structure and reactive capacity of natural all-carbon composites. Based on the research findings, methane formation during an outburst occurs owing to the breakage of =СН– fragments in the structures with sp2-hybridization and –СН₃ fragments in the structures with sp3-hybridization of electron shells. The authors obtain quantitative estimates of methane amount formed during two real outbursts by the ratio of carbon in aromatic and methyl groups of coal produced by an outburst and sampled from the bed nearby the outburst site. The estimates are obtained under assumption that all carbon is preserved in the aromatic group after the outburst, and each detached methyl group finds its atomic hydrogen for methane formation as hydrogen amount formation exceeds greatly the amount of methyl groups under an outburst since nearly any chain in the coal fringe ends with hydrogen and its bond energy in coal can be very low.
This research work was carried out with the support of the grant of the Russian Foundation of Fundamental Research 16-05-00584.

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