We hope to be able to work with Black Mountain Fuels in the research and development of wood torrefaction.

Torrefaction is a process used to produce high-grade solid biofuels from various sources of woody biomass or agro residues. The end product is a stable, homogeneous, high quality biofuel with far greater energy density and calorific value than the original feedstock, providing significant benefits in logistics, handling and storage, as well as opening up a wide range of potential uses.

Torrefaction is a thermal process that involves heating the biomass to temperatures between 250 and 300 degrees Celsius in an inert atmosphere. When biomass is heated at such temperatures, the moisture evaporates and various low-calorific components contained in the biomass are driven out. During this process the hemi-cellulose in the biomass decomposes which transforms the biomass from a fibrous material into a product with excellent fuel characteristics.

Torrefied biomass has seven immediate benefits over untreated biomass:

  • Higher calorific value
  • More homogeneous product
  • Higher bulk density
  • Excellent grindability
  • Durability
  • Hydrophobic nature/water resistance
  • No biological activity

Torrefaction of biomass results in a high grade biofuel which can be used as a replacement of coal in electricity and heat production and as fuel for gasification processes in the production of high value biobased fuels and chemicals.

Torrefaction process takes place in reactors. The incoming wood chips, which typically have a moisture content between 40-50% (fresh wood), are first dried. After drying the wood chips enter the torrefaction process. The volatiles released in the torrefaction process contain up to 10% of the energy stored in the wood chips (dry basis). Burning these volatiles in a combustor supplies the heat for the drying and torrefaction process. After the torrefaction step the torrefied wood chips (torchips) are cooled down. The bulk density of the material is increased by first grinding the torchips and then compacting the material in so-called pelletisers, similar to the way wood pellets are made.