Prediction of coal reactivity during combustion and gasification by using petrographic data

Abstract

Petrographic data were correlated with calorific value, oxygen content, fuel ratio, ignition temperature, oxygen chemisorption and selected gasification reactivity data of twenty one Canadian coals (17 from Western and 4 from Eastern Canada). Both parameters are suitable for predicting other coal properties particularly in the absence of mineral matter effects. Using ignition temperature and oxygen chemisorption the series of coals can be divided into three groups. The first group, characterized by low ignition temperatures and low oxygen chemisorption, had mean vitrinite reflectance and/or petrofactor less than 0.6 and/or 7.0. The second group, characterized by the largest oxygen chemisorption and intermediate ignition temperatures had mean vitrinite reflectance and/or petrofactor in the range of 0.6 to 1.0 and/or 7.0 to 11.0. The third group, characterized by the highest ignition temperatures and the lowest oxygen chemisorption had mean vitrinite reflectance and/or petrofactor greater than about 1.0 and/or 11.0. Calorific value and ignition temperature are good correlating parameters for low rank coals, whereas fuel ratio is suitable for higher rank coals. The petrofactor as a correlating parameter offered little advantage compared with the mean vitrinite reflectance.