Several commonly used combustion reaction kinetic models were introduced.On the basis of the co-combustion experiments of coal blends at constant high temperature

the homogeneous reaction model

one-dimensional diffusion model

and spherical symmetry shrinking core model were employed to carry out kinetic calculation for coal blends combustion at constant high temperatures.The combustion reaction dynamic parameters of the coal blends with different mixing ratios at high temperatures were obtained

and the simulated results were also compared with the experimental results.Moreover

by introducing an index called determination coefficient

the accuracy of the above three models were verified.The results show that

the dynamic parameters calculated by the above three models changed in the same trend

namely

both the activation energy and frequency factor decreased as the mixing ratio increased.For mixtures of Xinjiang lignite and other coals

the activation energy and frequency factor ranked in such order when different coals were mixed:Shenhua anthraciteDatong bituminousYunnan lignite.All the above three models can accurately reflect the nature of mixture combustion

to some extent.However

as models for solving kinetic parameters

each model had its own limitations.At the same temperature(1 400 ℃)

the maximum and minimum determination coefficients of the homogeneous reaction model and the one-dimensional diffusion model were low and the span was large.While that of the spherically symmetric shrinking core model was higher

indicating the spherically symmetric shrinking core model has higher simulation precision.