Influence of Pyrolysis Condition and Coal Type on Gasification Reactivity of Charcoal

The correlation of solid charcoal gasification reactivity with pyrolysis condition and coal type was investigated. The CO2 gasification of char observed under variant pyrolysis pressures,final temperature and coal type was analyzed using pressurized thermogravimetric coupled with ambient thermal analyzer. Based on the summary of the variant indexes of char reactivity,specific maximum gasification rate(Rs,max) and mean gasification rate were put forward to indicate the gasification reactivity of char. Specific maximum gasification rate can be used to point out the maximum reactivity of char,it decreases with pyrolysis firstly and get the minimum value at 3 MPa,then it increases with pyrolysis pressure increasing further;while it shows different trend with final temperature. Xiaolongtan brown coal char shows higher gasification reactivity whereas char of Shenfu bituminous coal and Pingzai anthracite coal shows lower Rs,max. Mean gasification rate(Rm) can displayed the process characteristics and burnout property of char gasification. Combined with Rs,max and Rm,it can describe the gasification property of char comprehensively. It can supply important reference for the design of coal gasification unit.