Ignition and Kinetic Studies: The Influence of Lignin on Biomass Combustion

This study investigates the relationship between the thermal behavior of nine biomass samples during combustion and lignocellulosic composition. The lignocellulosic composition was determined via standard biological assays, and it was observed that in most samples, cellulose is the most abundant organic component. Combustion kinetics and thermal behavior were examined using thermogravimetric analysis, while an Ash Fusion Furnace equipped with camera was used to monitor ignition temperatures in real time. The kinetic studies were repeated at heating rates of 5, 10, and 17.5 °C/min. All derivative thermogravimetric graphs, for each biomass, show two distinct peaks, thus suggesting two major reaction stages. Linear correlations were found between lignocellulosic composition of biomass and its combustion kinetics (both first and second stage), DSC peak temperature, as well as the ignition point of biomass. This is associated with the chemical characteristics and biological arrangements of lignocellulose in plant cells. Such tests potentially provide a quick and straightforward indication for selecting highly reactive and efficient biomass for combustion processes, which is linked directly to biomass composition.