Baranovsky V.I, Savitsky V.V., Burchak О.V. Mechanism of gas-generation track formation in сoal

Geoteh. meh. 2018, 141, 41-49

https://doi.org/10.15407/geotm2018.141.041

MECHANISM OF GAS-GENERATION TRACK FORMATION IN СOAL

1Baranovsky V.I, 2Savitsky V.V., 1Burchak О.V.

1Institute of Geotechnical Mechanics named by N. Polyakov of National Academy of Sciences of Ukraine, 2 Ye..O. Paton Electric Welding Institute of the National Academy of Sciences of Ukraine

UDC 552.574.08:[622/411/332:533.17]:620.179.1

Language: Ukrainian

Annotation.

The article is devoted to origin of structural transformations in the solid component of fossil organic matter under the external thermal influence, which results in release of volatile low-molecular compounds. The paper presents results of experimental studies of gas-generation processes in coal obtained by methods of electronic shearography and coal petrography. The methods of petrography of the coal samples at all stages of metamorphism recorded microdefects of coal bed structure in the form of gas "bubbles" with a channel for generated gases drainage. The possible mechanism of microdefect formation in the coal bed is presented. The conclusion made is based on the results of experimental studies of internal defects in the matter conducted by the non-destructive methods of control according the original methods designed by the E.O. Paton Electric Welding Institute. With the help of the methods of electronic shearography, it was experimentally proved that under the influence of weak heat fluxes in the coal, structural stresses occurred due to the heterogeneity and defect of the matter structure. In the rock massif, energy relaxation of these stresses in the coal molecular structure occurs due to the free radical transformations, which are accompanied by release of the fluids. At the micro level, consequence of the transformations is formation of gas "bubbles" and fractured porous structure of coal. Structural transformations in the coal organic component are in full compliance with the physicochemical model of transformations with release of gaseous hydrocarbons. Combined use of the two independent methods of investigation allowed to determine nature of defects in the coal seam structure and mechanism of formation and dynamics of gas "bubbles" as traces of volatile low-molecular compounds generated by the solid coal substance. In the conditions of constant heat flow from under the Earth's interior, the processes of gas generation in the carbon-bearing massif are permanent, though differ by speed of their development.

Keywords:

coal, structural transformations, gas generation, electronic shearography, coal petrography

References

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About the authors

BaranovskyVolodymyr Ignatovych, Master of Science, Junior Researcher in Department of Geology of Coal Beds at Great Depths, Institute of Geotechnical Mechanics named by N.S. Poljakov of National Academy of Sciences of Ukraine (IGTM NASU), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. .

Savitsky Viktor Volodymyrovych, Candidate of Technical Sciences (Ph.D/), Senior Researcher of Ye.O. Paton Electric Welding Institute of the National Academy of Sciences of Ukraine, (PWI NASU), Kyiv, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.

Burchak Oleksandr Vasylyovysh, Doctor of Geology (D.Sc.), Senior Researcher, Senior Research in Department of Geology of Coal Beds at Great Depths, Institute of Geotechnical Mechanics named by N.S. Poljakov of National Academy of Sciences of Ukraine (IGTM NASU), Dnipro, Ukraine, E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.