Research on coal's combustion characteristics and kinetics parameters as a function of its metamorphic degree

doi:10.16265/j.cnki.issn1003-3033.2017.09.011

Abstract

Abstract: For the sake of studying the influence of coal metamorphic grade on the heat release characteristics of coal combustion in coal mine fires, thermogravimetric experiments were carried out on 6 coal samples different from each other in metamorphic degree by using an STA 449C type synchronous thermal analyzer. DTG curves were obtained by differential calculation of TG curves. Kinetic parameters of combustion reaction were calculated for the 6 coal samples by using Freeman-Carrol model. The results show that the weight loss rate and the maximum weight loss rate decrease gradually with the increase of the metamorphic degree of coal samples,the DTG curves accord with Gauss distribution approximately, that the higher the coal sample moisture content is, the higher the initial exothermal temperature θ_f0 will be, that with the increase of metamorphic degree of coal sample, characteristic temperatures θ₁, θ₃, θ_s1 and θ₄ increase linearly and θ_s0 and θ_f0 decrease linearly that the amount of heat released is an exponential function the degree of coalification, that at the same temperature, there is a negative correlation between the heat quantity and the metamorphic degree, and that there is a positive correlation between the degree of coalification, and the five items, composite combustion characteristic index S, the heat quantity, the filtration activation energy, the ignition activation energy and combustion activation energy.

Key words: metamorphic degree, characteristic temperature point, initial exothermic temperature, heat release, combustion characteristic index, kinetic parameters

CLC Number:

BAI Gang, ZHOU Xihua, SONG Dongping, LI Xueming. Research on coal's combustion characteristics and kinetics parameters as a function of its metamorphic degree[J]. China Safety Science Journal, 2017, 27(9): 63-68.

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