Bezruchko K.А, Burchak О.V, Balalaiev О.К. Gas generation by coal matter in contemporary conditions

Geoteh. meh. 2019, 145, 15-23

https://doi.org/10.1051/e3sconf/201910900006

GAS GENERATION BY COAL MATTER IN CONTEMPORARY CONDITIONS

1Bezruchko K, 1Burchak О.V, 1Balalaiev О.К.

1Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences ofUkraine

UDC 552.578.14.2.061.4:552.574                    

Language: English

Abstract.

The natural gas content of coal deposits is mainly formed as a result of irreversible structural transformations of fossil carbonized organic matter. Under the action of external factors in the coal substance, transformations with the emission of stable low-molecular weight compounds are occurred, primarily methane and its homologues. A new approach for the study of processes at the atomic-molecular level occurring in the current situation in fossil carbonized organics was proposed. A new phenomenological model of physicochemical transformations in a metastable coal substance with the emission of fluids has been developed. The proposed physic/chemical model is based on the genetic connection of coal methane with fossil organic matter and determines the conditions for the activation of structural transformations in coalmines. The proposed physico-chemical model explains the formation of a metastable single-phase system of the “solid solution” type. The separated gas molecules are in the absorbed state inside the defects of the molecular structure, formed under the action of geomechanical forces. If, as a result of the relaxation of structural stresses in the organic substance of coal such a molecule is initially was formed on the surface or of a pore or crack, then it will be in the adsorbed state until the pressure decreases moment and the transition to the free state. This model describes the possible options for the coal/gas system development in the current situation. The accumulation of thermal and mechanical energy by coal in the form of structural stresses in an amount, sufficient to activate free-radical reactions, was experimentally established. In the undisturbed coalrock massif the processes of the coal molecular structure transformation have the relaxation character. The result of relaxation of the accumulated energy in the conditions of a gas-saturated coalrock massif is the methane generation by coal. Gas generation in the process of coalification, in its essence, is the energy response of the system to the action of external geomechanical options (temperature and pressure), by the way of releasing the accumulated additional energy with the emission of gaseous products and the destruction of the solid phase in the organic matter of the coal.

Keywords:coalrock massif, coal/gas system, structural transformations, free-radical reactions, methane generation by coal.

 

References

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About the author

Bezruchko Kostiantin Andriiovych, Doctor of Geology Science (D.Sc.), Senior Researcher, Head of the Department of Geology of Coal Beds at Great Depths, Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine (IGTM, NAS of Ukraine), Dnipro, Ukraine, Ця електронна адреса захищена від спам-ботів. вам потрібно увімкнути JavaScript, щоб побачити її.

Burchak Oleksandr Vasylovych, Doctor of Geology Science (D.Sc.), Senior Researcher, Senior Researcher of the Department of Geology of Coal Beds at Great Depths, Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine (IGTM, NAS of Ukraine), Dnipro, Ukraine, Ця електронна адреса захищена від спам-ботів. вам потрібно увімкнути JavaScript, щоб побачити її.

BalalaievOleksandr Kostiantynovych,Candidate of Beology Science (Ph.D.), Senior Researcher, Senior Researcher of the Department of Geology of Coal Beds at Great Depths, Institute of Geotechnical Mechanics named by N. Poijakov of National Academy of Sciences of Ukraine (IGTM, NAS of Ukraine), Dnipro, Ukraine, Ця електронна адреса захищена від спам-ботів. вам потрібно увімкнути JavaScript, щоб побачити її.