Abstract: An apparatus for preserving wood product comprising, in one embodiment, a treatment space sealable in medium-tight manner; a vacuum pump connected to the treatment space; a steam source connected to the treatment space; a heating device which is in thermal contact with the treatment space; a dispenser for adding predetermined amounts of either a base or an acid to the treatment space; pH measuring device for determining the pH value of steam in the treatment space; and measuring and control equipment adapted to monitor at least the pH temperature and pressure inside the treatment space and to control the vacuum pump, the steam source and the heat source, and the pH by dispensing either a base or an acid. Also disclosed is a method for preserving wood. The preservation process has a relatively short process time, wherein a good preservation is realized while the mechanical strength of the wood is largely retained. The amount of waste wood material is greatly reduced.

Abstract: An apparatus for preserving wood product comprising, in one embodiment, a treatment space sealable in medium-tight manner; a vacuum pump connected to the treatment space; a steam source connected to the treatment space; a heating device which is in thermal contact with the treatment space; a dispenser for adding predetermined amounts of either a base or an acid to the treatment space; pH measuring device for determining the pH value of steam in the treatment space; and measuring and control equipment adapted to monitor at least the pH temperature and pressure inside the treatment space and to control the vacuum pump, the steam source and the heat source, and the pH by dispensing either a base or an acid. Also disclosed is a method for preserving wood. The preservation process has a relatively short process time, wherein a good preservation is realized while the mechanical strength of the wood is largely retained. The amount of waste wood material is greatly reduced.