Classification of wood drying rooms (2)
3. According to the medium circulation characteristics. Divided into natural circulation drying room and forced circulation drying room. The natural circulation drying room uses the principle that the hot air rises when it is light, and the cold air is heavy when it descends to realize the circulation of the drying medium and achieve the purpose of drying. Therefore, in the natural circulation drying room, the gas flow direction is generally vertical. The circulation speed of the gas flowing through the pile is generally 0.2-0.3m/s. The forced circulation drying room uses a fan to make the gas flow in the drying room, and the circulation speed of the medium flowing through the material pile is generally above 1m/s. For uniform drying, the forced circulation is preferably reversible, that is, the direction of the gas flow through the pile is periodically changed.
4. According to heating method or energy type. It can be divided into steam heating drying room, furnace gas heating drying room, electric heating drying room, solar drying room, heat transfer oil drying room, hot water heating drying room, etc.
The steam heating drying chamber uses low-pressure saturated water vapor (pressure 0.4-0.6Mpa) as the heat carrier, and the drying medium in the chamber is heated by a steam heater to dry wood. The drying medium of this drying chamber can be humid air or superheated steam at normal pressure. The latter becomes the superheated steam drying chamber.
Furnace gas heating drying chamber uses the hot gas produced by burning waste wood, gas or oil as the heating medium. According to the specific heating method, it can be divided into three types: furnace gas drying room, furnace gas indirect heating drying room and hot air drying room. Furnace gas drying chamber uses furnace gas as the drying medium; furnace gas indirect heating drying chamber uses furnace gas as the heat carrier, and the indoor drying medium—humid air is heated through the furnace gas radiator; hot air drying chamber uses the drying medium through the hot blast furnace Direct heat before drying the wood.
Solar-heated drying rooms generally use solar energy as the main energy source to heat humid air and dry wood. Electric heating or wood waste heating is supplemented in special time or seasons when solar energy is insufficient.
Heat conduction oil heating drying chamber Use heat conduction oil instead of saturated water vapor as the heat carrier, and other facilities are the same as steam heating drying chamber during drying.
The hot water heating drying room uses hot water as the heat carrier, and the others are the same as the steam drying room.
