|
Computational
analysis of the coal self-heating model in a dense rock massiv
E.P. Feldman*1,
N.O. Kalugina1, O.V. Chesnokova1
1Institute for
Physics of Mining Processes of the National Academy of Sciences of Ukraine,
Dnipro, Ukraine
*Corresponding
author: edward.feldman.40@gmail.com
Physical and
technical problems of mining production, 2020, (22), 77-84.
https://doi.org/10.37101/ftpgp22.01.006
full
text (pdf)
ABSTRACT
Purpose. A numerical analysis of the processes of self-heating of a coal
massif section on the basis of a mathematical model that takes into account
the case of tight contact of coal with the rock at great depths of the
formation and conditions when the heat of the chemical reaction of coal
oxidation is transferred to the environment (enclosing rocks) only by the
heat conduction mechanism.
Methods. The work is based on solving the equations of thermodynamics by
numerical methods using mathematical computer programs.
Findings. As a result of a numerical analysis of the constructed
mathematical model of coal self-heating in a compact coal mass in the
presence of an oxygen source near the bed, the results of an asymptotic
analysis confirming that the temperature of the coal rises, albeit slowly,
but unlimitedly, and reaching the constant temperature mode for all, the
value of the coefficient of heat transfer and thermal diffusivity of the
rock is absent.
Originality. By numerical
calculations, the theoretical model of coal self-heating in a dense rock
mass is studied, when the heat of the chemical
reaction of coal oxidation is transferred to the host rocks only by the
heat conduction mechanism. The calculations were carried
out for the case when the host rocks are heated near the surface of
their contact with coal and the density of the heat flow from coal to rock
is determined by the difference in the contact temperatures of coal and
rock.
Practical
implications. The results obtained can be useful for updating the fire hazard
forecast under appropriate environmental conditions. They allow us to
describe the process of low-temperature self-heating of compact coal seams
over a wide range of changes in the basic thermophysical
parameters of coal and rocks, and can be the basis for predicting the
endogenous fire hazard at great depths.
Keywords: coal,
oxygen, self-heating, spontaneous combustion, fire.
REFERENCES
1. Shcherban' A.N., Kremnev
O.A. (1951). Issledovaniye koeffitsiyentov
teploprovodnosti v mo-delyakh
gornykh vyrabotok, Kiyev: Iz-vo AN
USSR.
2. Feldman, Е.P., Kalugina, Т.О., & Chesnokova, О.М. (2018) Matematychna
modelʹ teploperenosu u vuhilʹnomu
plasti na velykykh hlybynakh. Fizyko-tekhnichni problemy hirnychoho vyrobnytstva,
(20), 914.
3. Feldman, Е.P., Kalugina, Т.О., & Chesnokova, О.М. (2019) Asymptotychnyy analiz modeli samonahrivannya vuhillya. Мozhlyvosti prohnozu pozhezhonebezpeky. Fizyko-tekhnichni problemy hirnychoho vyrobnytstva,
(21), 106115.
4. Veselovskiy V.S., Vinogradova
L.P., Orleanskaya G.L. (1972). Fizicheskiye osnovy samovoz-goraniya uglya i rud. Moskva: Nauka.
|
