impregneringsanläggning

An impregneringsanläggning is an industrial facility where timber and other porous materials are treated with chemical preservatives to improve durability and resistance to decay, fungi, and wood-boring insects. The aim is to extend service life in outdoor or humid environments.

Typical treatment involves conditioning the wood, placing it in a treatment vessel, applying a vacuum to remove air, and then introducing preservative under controlled pressure so the chemical penetrates and binds within the wood. After impregnation, the material is dried or conditioned to the target moisture content. There are several process variants and preservative formulations (waterborne or oil-based) chosen according to wood species and end use.

Plants are equipped with autoclaves or impregnation tanks, dryers or kilns, and recovery or effluent-treatment systems. Process controls regulate temperature, pressure, and timing, while quality control measures determine preservative retention, penetration, and moisture content. Environmental and worker-safety considerations require handling of spent preservatives, proper ventilation, containment of effluents, and use of protective equipment in accordance with applicable regulations.

Applications include structural timber, fence posts, utility poles, railway sleepers, and outdoor joinery. In recent decades, the industry has shifted toward copper-based and other modern preservatives with improved environmental performance and treatability, while older formulations such as creosote or CCA have been restricted in many markets.

Terminology: impregneringsanläggning denotes a plant where wood impregnation and related drying and conditioning take place as part of wood preservation under national and regional standards.