Vitrinite-rich coal concentrate intrinsic reactivity index

Abstract

This work defines a new reactivity coal combustion parameter called intrinsic reactivity index (IRI), combining reactive maceral fraction (vitrinite/liptinite), non-reactive maceral fraction (inertinite/intrinsic mineral matter) and vitirinite reflectance averages. Coal samples from La Yolanda and Guachinte (Valle del Cauca) collieries were used to evaluate the IRI; samples consisted of original and vitrinite concentrated fractions obtained from froth flotation column. This new parameter was compared to three conventional parameters: weighted mean activation energy (WMAE), peak temperature (PT) and final temperature (FT). Results revealed that vitrinite concentrated fractions had higher IRI figures than original coal. This meant that vitrinite concentrated fractions presented higher reactivity to combustion than original coal. Results also showed that EAMP TP and TF decreased with an increase in IRI, suggesting that coal combustion reactivity becomes improved when vitirinite concentration in coal is increased.