STATE OF THE ART REVIEWS

COST ACTION E22: Environmental optimisation of wood protection
Working Group 3: INNOVATIONS
Scope: Application of modified wood, heat treatment, insect growth regulators, new
biocides, non-biocidal treatments, resins and oils
The activity of WG3 will be particularly oriented towards two major objectives:
• heat treatment;
• application of modified wood.
Heat treatment
As regarding the heating treatment, we could mention three treatment procedures
(drying, steaming and thermic shock) that have some effects over:
- dimensional stability of wood;
- wood plasticity;
- colour homogeneity;
- a better penetration of the preservatives into the wood structure;
- decrease of wood biodegradability;
- improvement of the technological features.
The drying procedure represents an important stage in wood processing, that
should provide characteristics suitable for a proper and high performance of wood
utilisation.
The steaming is a hygro-thermic process, which is particularly addressed to the
beech species (representing about 567% of the sawntimber production and featuring
a significant percentage in the furniture, parquetry and flooring board production).
The steaming follows shortly after sawing, by using direct steaming in special
chambers.
Studies have been undertaken on the effects of the steaming and drying processes
over:
- colour changes;
- evacuated water weight;
- wood shrinkage;
- density;
- strength to fiber parallel compression;
- strength to fiber parallel tension;
- Young modulus;
- shear strength;
- stress strength.
132