Factors Influencing CO_2 Gasification of Hunyuan Coal Char and the Kinetic Characteristics

The effect of pyrolysis temperature,coke-forming time and gasification temperature on the CO2 gasification of Hunyuan coal char was studied,during which a dynamic model was obtained for the gasification reaction.Results show that the gasification reactivity of Hunyuan coal char decreases along with the increment of temperature.There may exist an optimal pyrolysis time at a specific temperature,which may decrease with the increment of gasification temperature.Improving the gasification temperature can remarkably increase the gasification reactivity,on which the gasification temperature has a stronger impact than the pyrolysis temperature.The gasification reactivity of coal char formed at lower pyrolysis temperatures increases obviously with rising gasification temperature.When the gasification temperature gets above 900 ℃,the gasification reactivity of coal char will have a slight change.It is recommended to use volumetric model to describe the gasification process of Hunyuan coal char,compensation effect exists among the kinetic parameters,in which the iso-kinetic temperature has been computed to be 1 199.6 ℃.