Torrefaction process of biomass material is essential in converting them into biofuel with improved calorific value and physical
strength.However, the production of torrefied biomass is loose, powdery, and nonuniform. Onemethod of upgrading thismaterial
to improve their handling and combustion properties is by densification into briquettes of higher density than the original bulk
density of the material. The effects of critical parameters of briquetting process that includes the type of biomass material used
for torrefaction and briquetting, densification temperature, and composition of binder for torrefied biomass are studied and
characterized. Starch is used as a binder in the study. The results showed that the briquette of torrefied rubber seed kernel (RSK) is
better than torrefied palm oil shell (POS) in both calorific value and compressive strength. The best quality of briquettes is yielded
from torrefied RSK at the ambient temperature of briquetting process with the composition of 60% water and 5% binder. The
maximum compressive load for the briquettes of torrefied RSK is 141N and the calorific value is 16MJ/kg. Based on the economic
evaluation analysis, the return of investment (ROI) for the mass production of both RSKand POS briquettes is estimated in 2-year
period and the annual profit after payback was approximately 107,428.6 USD
