Torrefaction is not a new process. The Vikings were already using it to enhance the resistance and durability of wood back at the turn of the 8th century.
Scandinavian countries have been improving this age-old procedure since the 1930s. Valutech-VTT is a proven technology that was developed for use in both the residential and commercial sectors in the past ten years.
What is torrefaction?
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1. Preheating and drying
First, the wood is gradually heated to approximately 130°C for about 20 hours. This process equalizes the material and lowers the moisture level to almost 0%.
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2. Intensive heat treatment
he wood is then heated to about 200°C to thermally modify its molecular structure. This procedure yields three effects: it gives wood a rich natural amber colour, the wood is much less subject to fluctuations in moisture levels, giving it unmatched stability and durability and the wood has much greater resistance to decay and insects.
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3. Cooling and conditioning
The temperature is then gradually lowered. During this phase, the controlled addition of water vapor brings the moisture level of the wood back to 4% to 7%. This restores natural flexibility, making it easier to work with.
How does torrefaction affect the molecular structure of wood?
