As a porous solid,coke exhibits typical non-uniform deterioration characteristics from the surface to the inside,which has a very important influence on the porosity of the coke layer in the blast furnace.Based on the basic principle of mass transfer reaction in the dissolution process of porous coke,the paper analyzes the characteristics of the heterogeneous evolution of coke pores,and further improves the determination and analysis methods of coke matrix reaction rate kv and pore diffusion coef-ficient Deff on the basis of previous research,and gives a more accurate and easy-to-measure param-eter,i.e.,√kv/Deff to characterize the non-uniform deterioration characteristics of coke pores,which provides help for improving the coke quality evaluation system.The results show that there is a strong heterogeneity in the pores with great size differences from nanoscale to millimeter scale,and the pores with different pore sizes obey different diffusion laws and equations,so the pore diffusion charac-teristics of coke should be considered separately and comprehensively evaluated.With the progress of the carbon loss reaction,the pores in the coke gradually expand or merge into mesopores and macro-pores,the stomatal diffusion coefficient gradually increases,and the instantaneous inhomogeneity of deterioration decreases.The smaller the coke √kv/Deff-value,the better the particle size uniformity after deterioration,which is beneficial to the air and liquid permeability of the blast furnace.
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