Patent attributes
A process for treating biomass comprises providing a material that contains an amount of residual moisture. The material is heated to a torrefying temperature in a low-oxygen atmosphere in a torrefaction reactor to convert it into a torrefied material. The material with the contained residual moisture is essentially fully dried in a drying chamber by evaporation of residual moisture. The torrefaction reactor comprises a torrefying chamber, in which the torrefaction of this dried material is essentially carried out. The material is conveyed through the torrefaction reactor. The drying of the material in the drying chamber is carried out by introducing into it a hot drying gas that flows therethrough cocurrently with the material. The torrefaction of the material in the torrefying chamber of the torrefaction reactor is carried out by introducing into it a hot torrefying gas that flows through the torrefying chamber countercurrently with the material.
