Influence of blending low-rank coals on gasification characteristics of gasification coke

Three types of coal blending for coking were screened out from seven types of coal samples.The three types of coal chars were prepared under different pyrolysis temperatures by using high temperature pyrolysis test device.The effect of temperature on the distribution of pyrolysis products was studied.The parameters of the char surface area, pore volume and pore size distribution were investigated to reveal the relationship between coal species and coke reactivity as well as coal coke characteristics.The results show that the yields of the three coal chars decrease with the increase of pyrolysis temperature, and the coal char prepared by blending CY/QM has the lowest yield under the same temperature.The specific surface area and pore volume of coal char increase with the increase of pyrolysis temperature if the temperature is below 1 150 ℃, and the reactivity of coal increases as well.The order of reactivity for coal char samples with different coal blending follows CY/QM> CY/QM/JM> CY/GSJM.However, the partial structure of coal char was collapsed when the pyrolysis temperature reaches 1 150 ℃, and its reactivity was no longer increased.Moreover, the difference in the reactivity of the coal chars prepared by the three types of coal blending is not obvious.