Impact of torrefaction on the grindability and fuel characteristics of forest biomass

Torrefaction increases bulk density and simplifies storage and transportation.

“increases bulk density and simplifies storage and transportation (Bergman, 2005;Phanphanich and Mani, 2011)”

Lignocellulosic biomass is associated with shortcomings like structural heterogeneity, non-uniform physical properties, low energy density, hygroscopic nature, and low bulk density.

“The lignocellulosic biomass, in spite of all its positive attributes, is associated with the different shortcomings like structural heterogeneity, non-uniform physical properties, low energy density, hygroscopic nature, and low bulk density.”

These limitations create difficulties in transportation, handling, storage, and conversion processes.

“These limitations create difficulties in transportation, handling, storage, and conversion processes (Arias et al., 2008;Phanphanich and Mani, 2011;Medic et al., 2011;Uemura et al., 2011;Wannapeera et al., 2011).”

Torrefaction reduces grinding energy.

“reduces grinding energy (Repellin et al., 2010;Phanphanich and Mani, 2011)”

Torrefaction improves particle size distribution.

“improves particle size distribution (Phanphanich and Mani, 2011)”

The mean particle size of ground torrefied biomass decreases with torrefaction temperature.

“The mean particle size of the ground torrefied biomass as shown in the Fig. 16 decreases with the torrefaction temperature (Deng et al., 2009;Phanphanich and Mani, 2011).”

A decrease in specific grinding energy by one-tenth (from 237.7 kWh/tonne to 23.9 kWh/tonne) for pine chips, and one-sixth (from 236.7 kWh/t to 36.7 kWh/t) for logging residues, was noted when biomass was torrefied at 300 °C for 30 minutes.

“A decrease in a specific grinding energy by one-tenth (from 237.7 kWh/tonne to 23.9 kWh/tonne) for pine chips, and one-sixth (from 236.7 kWh/t to 36.7 kWh/t) for logging residues was noted when the biomass was torrefied at 300 °C for 30 minutes (Phanphanich and Mani, 2011).”

The particle size distribution curve skews more towards lower particle sizes at different torrefaction temperatures compared with untreated biomass.

“The particle size distribution curve also skews more towards lower particle sizes at different torrefaction temperature compared to untreated biomass (Phanphanich and Mani, 2011;Repellin et al., 2010).”

Phanphanich and Mani (2011) found a fineness fraction of 82% in pine chips and 51% in logging residues.

“For example, Phanphanich and Mani (2011) found the fineness fraction of the particle 82% in the pine chips, and 51% in the logging residues.”