Impregnated Wood

Vacuum pressure impregnation
6.The excess solution is draw off during the final vacuum, so that the timber ca be removed from the pressure vessel drip – free

Vacuum pressure impregnation
7. The vessel is aerated , the treated timber is removed and placed in covered storage to allow fixation

Vacuum pressure impregnation
The stronger the vacuum, the more protective solution can be absorbed
Wood species are very different in their permeability levels.
Much longer vacuums and pressure phases must be selected for spruce than for pine. 

The negative side of impregnation
chemicals are used for impregnation
especially during the Soviet Union for impregnation solutions were used heavy metals such as copper and chromium and other chemicals
Burning impregnated wood in big amounts may cause air poisoning and pollution
If used properly and for the intended use, preserved wood does not cause health risks for humans.

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