Combustion behavior and kinetics of biochar

This study investigates combustion behavior and kinetics of biochars derived from three common agricultural residues — sugarcane bagasse, rice straw, and rice husk — as well as their binary blends, to assess their suitability as bioenergy fuels. Nature Using thermogravimetric analysis (TGA) and a distributed activation energy model (DAEM), the authors evaluate key combustion parameters including ignition temperature, peak combustion rate, burnout temperature, and activation energy for different feedstocks and their mixtures. Nature

Results show that the combustion characteristics of biochars are similar to those of coal: they exhibit high fixed carbon content, low volatile matter compared to raw biomass, and enhanced heating value (HHV). Nature Among the biochars tested, sugarcane bagasse char showed the highest fixed carbon and favourable combustion profile. Nature The activation energy for char combustion was found to be relatively high (~ 247.6 kJ/mol), indicating stable combustion, while decomposition of partially degraded lignin had lower activation energies (130.8–175.5 kJ/mol), varying with feedstock type. Nature

Importantly, biochar blends — combining chars from different residues — retained good combustion characteristics and often outperformed single-feedstock biochars, suggesting that such blends can be used in existing industrial boilers as a sustainable, carbon-neutral alternative to coal. Nature Overall, the paper supports large-scale biomass residue valorization via pyrolysis and combustion as a viable route for waste-to-energy conversion.