What are the advantages of a wood drying room or wood dryer?

With the development of the times, the supply of furniture has far exceeded market demand. Therefore, furniture drying has entered the era of high technology. Many furniture processing companies now use high-temperature heat pump wood dryer.

Heat pump wood dryer drying process:

1. Install the wood according to the display standards, close the drying room, and turn on the control system.

2. Preheating: Turn on the heat pump and fan, and set the upper temperature limit to 45°C. To save preheating time, activate the electric assist system, and control the heating and holding time from the ambient temperature of 20°C to 45°C within 14 hours. During this stage, the heat pump energy efficiency ratio is around 3.5, operating at full capacity, and the fan is operating at full capacity.

3. Heating: Since the base temperature for the previous drying stage is 62°C, during the heating process, due to the high initial moisture content of the wood, the evaporation of moisture from the wood ensures that the temperature and humidity are synchronized. At the same time, the electric assist system is activated to maintain the heat balance caused by humidification and heating.

4. First-stage drying: Set the temperature at around 62°C. After steaming, the wood releases moisture quickly, and this is the initial stage of free water removal. Standard technology adjusts the wood temperature to a high interior and low exterior. This stage allows for rapid removal of over 40% of free water. Assuming the wood has a moisture content of 45% upon entering the kiln, 900 kg of water must be removed from 2,000 kg of wood. Assuming a 12P dryer removes 30 kg of water, this process takes 30 hours.

5. Second-stage drying: Set the temperature at 66°C. At this point, the wood's moisture content is still above the fiber saturation point, and the water removal rate is relatively high. Increasing the drying temperature and lowering the relative humidity ensure rapid moisture removal, reducing the moisture content from 40% to 30%.

6. Third-stage drying: Set the temperature at 72°C. When the wood moisture content is above 25%, set the temperature to 60°C. At this point, the wood's moisture content is close to the fiber saturation point, and rapid drying may cause drying defects. The drying process can be accelerated from 30% to 25%.

7. Moisture Control Drying: When the wood moisture content reaches 25%, it has reached fiber saturation. To ensure wood drying quality, an intermediate treatment is required to accelerate subsequent drying.

8. Four-Stage Drying: After moisture control, the temperature is adjusted back to 72°C. This significantly accelerates drying speed, and the chance of drying defects in the treated wood is greatly reduced.

9. Five-Stage Drying: When the wood moisture content drops below 20%, the drying speed slows. At this point, the temperature must be raised to achieve a relatively dry relative humidity, forcing the moisture inside the wood to drain quickly.

10. Six-Stage Drying: When the wood moisture content drops below 15%, the moisture content is already very low, and the drying speed is slower than in any of the previous stages. At this point, the temperature is raised to 80°C.

11. Equilibrium Treatment: When the wood moisture content reaches 12%, it has reached or is close to the required moisture content before leaving the kiln. However, the drying stress in the wood has not yet been eliminated, and the moisture distribution within the wood is not yet uniform. Therefore, a final equilibration treatment is required.

12. Cooling and Kiln Exit: After the balancing treatment, the wood's moisture content is essentially balanced and drying stress is largely eliminated. The wood can be removed from the drying room only when the temperature drops to 35°C (10-15°C higher than the ambient temperature).

Wood Drying Room Options

The drying room size and ventilation method are determined based on the length, thickness, placement, and quantity of the wood.

Wood Drying Unit Options

A 12P dryer has a power of 11.12 kW, consumes 8-10 kWh per hour, and dehydrates approximately 30 kg per hour. Auxiliary equipment and a fan form a circulation system within the drying room.