Thermo Treatment

New heat treatment process results in very durable wood already at low temperatures

The newly developed heat treatment process is now available with a very effective heat transfer made possible through a heated double casing of the pressurized autoclave in stainless steel. The process is very swift, particularly gentle and commercially feasible. Wear parts like for instance ventilators are not needed in the plant. A specialty of the process is that the wood is not fully dried during the process: A residual moisture content of approx. 6% HF is retained.

The high rate of wood rejection which one often sees with traditional thermo treatment processes, where the wood is completely dried out, is minimized in the WTT process. The assumption that a pressurized thermal process reaches its full performance in the temperature range of 160--180°C, has been investigated in recent months at the Freiburg University Freiburg in Breisgau, Germany.

The university conducted investigations where the WTT heat-treated wood was examined in relation to the normal standards EN 350-1, EN 113, DIN-84, and EN 807. Extensive statistical and biological tests have been carried out for six types of wood (oak, beech, ash, pine, spruce and fir).

The summary of the biological results of wood:

Durability test (EN 350-1, EN 113 with EN 84) at 180°C treatment temperature