1. Drying stage of wood drying equipment: operate accor […]
1. Drying stage of wood drying equipment: operate according to the process benchmark requirements, prevent temperature fluctuations in the heat preservation stage, and prevent the temperature from rising too fast when adjusting the benchmark stage;
2. Determine the preheating temperature according to different tree species and thickness. Generally, the initial preheating temperature does not exceed 45 °C, and most of them are lower than 40 °C. During preheating, the wood must be heated through to enter the drying stage, and steam can be sprayed if necessary;
3. Intermediate treatment: The intermediate treatment is to spray steam into the kiln to adjust the humidity of the air in the kiln. During the drying process, it is necessary to observe and record the speed of wood moisture change. The operator should enter the kiln to observe whether cracking and deformation occur on the surface of the wood. If it occurs, it must be recorded and marked. Inject steam into the kiln in time for the changes in the situation. The steam injection time should be guaranteed, but it should not be too long. Generally, the thickness of one centimeter is 2.0 hours. The intermediate treatment temperature is consistent with the requirements of the reference stage. The relative humidity is 5-8% higher, and the number of intermediate treatments can be carried out in time as needed;
4. Balancing treatment of wood drying equipment: It is to eliminate the difference in moisture content between different wood piles in the kiln, and ensure that the moisture content of all wood meets the requirements when leaving the kiln. In the later stage of drying, it can be found that most of the probes have high moisture content, and a few have reached the requirements. In order to make the wood in the kiln pass the kiln, balance treatment must be carried out. The balance treatment temperature is consistent with the final benchmark requirements, and the relative humidity requirements are higher than the final moisture content. The relative humidity of 2% lower equilibrium moisture content, the time is until the final moisture content of each probe is uniform;
5. Final high-humidity treatment: It is to eliminate the unevenness of wood thickness inside and outside. The high-humidity treatment temperature is equal to the baseline final stage temperature, and the relative humidity is the relative humidity of the equilibrium moisture content that is 4% higher than the final moisture content.
6. Cooling out of the kiln: The temperature in the later stage of drying is relatively high. In order to prevent the hot wood from bursting when it leaves the kiln, the wood must be cooled before it can be discharged from the kiln.