Biomass torrefaction characteristics in inert and oxidative atmospheres at various superficial velocities

- Non-oxidative and oxidative torrefaction of biomass are studied.
- The superficial velocity or volumetric flow rate of carrier gas is altered.
- Thermal degradation of biomass in N2 is controlled by internal heat and mass transfer.
- Torrefaction reaction of biomass in air is dominated by surface oxidation.
- There exists an upper limit of air superficial velocity in the decrement of solid yield.