Volatile matter release and thin and thick char formation as a function of vitrinite content, coal rank, time and temperature devolatilization

Abstract

Pulverized coal combustion is determined by char chemical reactivity, which depends of its morphology developed during the devolatilization process. In this work, some empirical relationships were obtained, in order to determine the  composition  of  thin  and  thick  walled  char,  as  well  as  volatiles  liberation,  as  a  function  of  process  variables  (temperature  and  time  devolatilization)  and  coal  properties  (vitrinite  content  and  vitrinite  reflectance).  Those empirical models can be used to improve the combustion modelling and to simulate the char chemical reactivity. It was found that the empirical models, to predict different char morphology, gave a good approximation from coal properties and characteristic parameters of the devolatilization process, involving coal rank.