Air humidity control in drying kiln


Humidity control of air in a wood drying kiln.
When you build a wood drying kiln, pay special attention to control of air humidity. Air humidity is a very important parameter in the drying process of wood.

Reducing of humidity for reversible airflow.

drying-kiln-humidity-001 drying-kiln-humidity-002
When the air flow moves in the forward direction - the air moves to the inside of the wood drying kiln through the pipe 1 and to the out through the pipe 2.
When the air flow moves in the reverse direction - the air moves to the inside of the kiln through the pipe 2 and to the out through the pipe 1.
In the first figure pipes are laid up through the roof. In the second figure pipes are laid through walls.
If the pipes are laid up, they must be short. If the pipes are long, large natural draft and humidity reduction system works poorly.

Reducing of humidity for non-reversible airflow.

drying-kiln-humidity-000
Air flow moves always in the forward direction - the air moves to the inside of the wood drying kiln through the pipe 2 and to the out through the pipe 1.
This scheme allows to take the air not only from the outdoors, but also from the indoors, for example, from the boiler room. Also for an extract, you can use a small fan with high pressure. Diameter of pipes becomes smaller, and the scheme will be easier.

Increasing of air humidity in a wood drying kiln.
If you are going to dry only softwoods (pine, etc.), an air humidifier is not a compulsory thing.
If you are going to dry and hardwoods (oak, etc.), an air humidifier is always needed.