On the reactivity of various biomass species with CO2 using a standardised methodology for fixed-bed gasification

A standardised method for studying the kinetics of CO2 gasification was applied to seven different biomass species from Europe and Asia. The aim was to gain a truer understanding of variations in feedstock behaviour inside fixed bed biomass gasifiers. Slow heating rates and fixed variable in-situ pyrolysis was followed by gasification at isothermal temperatures from 800 °C to 950 °C. There was closer similarity in reactivity between all species in the region of 900≤°C≤950 suggesting that these temperatures could be optimal for the design of generic gasifier settings. Values of activation energy were in the range of 159≤kJ mol−1≤216 for European arboreal species plus Sugar Bagasse. Coconut Coir and Jute had CO2 gasification characteristics that were distinct from the other species (lower activation energy and higher reactivity), particularly at lower temperatures of 800≤°C≤875. CO2 gasification thermolysis was found to develop as predicted by the theoretical random pore model; and a unique episode of ultra-low temperature devolatisation was observed during pyrolysis of Sugar Bagasse samples.