The microwave drying machine is an advanced drying device that uses microwave energy to heat and dehydrate materials quickly and evenly. It allows drying to be completed at relatively low temperatures, which helps reduce damage to the nutritional content of food.
Compared with traditional hot air drying, microwave drying rapidly evaporates moisture, significantly shortening the drying time. By adjusting the frequency and power of the microwave radiation, the machine enables precise control over different types of food, improving drying efficiency while saving time and energy.
Microwave drying machines are widely used for drying vegetables, fruits, meat, seafood, pet food, tea leaves, dried fruits, and other food materials. They offer a faster, more convenient drying solution and bring greater efficiency and benefits to food processing businesses.
Advantages of Shuliy microwave drying machine
- Fast Heating: Microwave heating is different from traditional methods—it makes the material itself generate heat, so there’s no need for heat conduction. The material reaches the target temperature almost instantly.
- Even Heating: Microwaves penetrate the material, heating it from the inside out. This ensures uniform heating and avoids the problem of being burnt outside but raw inside.
- Energy Efficient: Microwave heating has very little energy loss. Compared to electric or infrared heating, it can save more than 30%–50% of energy.
- Heating and Sterilizing at the Same Time: Microwaves have both thermal and biological effects, allowing sterilization and mold removal at lower temperatures. Fast heating helps preserve nutrients and natural color.
- Easy to Control: With a PLC control system, microwave power can be adjusted easily. The heating starts and stops instantly, enabling continuous and automated production.
- Safe and Low Radiation: The machine uses a microwave suppressor to prevent leakage. Microwaves are safely contained, and no radiation or harmful substances are released.
- Eco-friendly: The drying process produces no harmful gas, no waste heat, and no dust pollution.
What are the components and working principles of a microwave dryer?
Microwave Heating Chamber
Microwaves evenly distribute inside the sealed chamber and penetrate the material. This causes water molecules inside to vibrate rapidly, generating heat for fast and uniform drying.
Microwave Generator (Magnetron)
It converts electrical energy into microwaves at a frequency of 2.45 GHz and sends them through waveguides into the heating chamber to heat the material from inside.
Control System
Using a PLC with a touchscreen interface, the user can set and adjust microwave power, drying time, start/stop the machine, and monitor the process for automated and precise control.
Rotating Tray
Driven by a motor, the tray rotates the material inside the chamber so the microwave energy heats it uniformly, avoiding uneven drying or burning.
Mechanical Conveyor System
Materials are transported on stainless steel mesh belts or heat-resistant conveyor belts continuously into the drying chamber and out when drying is complete, enabling continuous or semi-continuous drying.
Material Safety
All parts in contact with the materials are made of food-grade stainless steel (SUS304). The conveyor belt material is stable and does not chemically react or adsorb substances from the materials.
Technical specifications of microwave drying machine
SL-3
| Item | Specification |
| Power supply | 380V±5% 50Hz±1% 3PHASE |
| Microwave Output Power | 8kw |
| Number of trays | 3 pcs |
| Capacity | 5-7.5kg/batch |
| Microwave frequency | 2450MHz±50MHz |
| Overall Dimension | 1400×1200×1600(mm) |
| Microwave heating box | 1000*900*1000(mm) |
| Diameter of trays | 500mm |
| Tray speed | 0-40 circle /min(adjustable) |
| Temperature range, accuracy | 0-300℃ (adjustable) |
SL-6
| Item | Specification |
| Power supply | 380V±5% 50Hz±1% 3PHASE |
| Microwave Output Power | 12kw |
| Number of trays | 6 pcs |
| Capacity | 10-15kg/batch |
| Microwave frequency | 2450MHz±50MHz |
| Overall Dimension | 1400×1600×2000(mm) |
| Microwave heating box | 1000*1000*1400(mm) |
| Diameter of trays | 500mm |
| Tray speed | 0-40 circle /min(adjustable) |
| Temperature range, accuracy | 0-300℃ (adjustable) |
Wide applications of microwave drying machine
The microwave dryer can be widely used in food, fruit, condiments, flowers, medicine, and the chemical industry, etc.
How to operate the microwave drying machine
Startup procedure
- Turn on all main power switches and the air switch.
- Release the emergency stop button. The control cabinet screen will light up, showing a clear view inside the drying chamber.
- Press the exhaust fan start button. The white start indicator light on the control cabinet will turn on. This activates the exhaust fan and dehumidifying fan. Check that the small fan inside the machine, the exhaust fan, and the dehumidifying fan are all running properly.
- Set the temperature parameters according to the drying process requirements.
- Place the material on the tray inside the drying chamber.
- Turn on the conveyor switch and adjust the frequency speed controller so the tray rotates, ensuring even heating of the material.
- Turn on the microwave start switch. The microwave current meter will indicate whether the microwave is working properly. Under normal operation, the current meter should show 2.4A and 2.4A.
Shutdown procedure
- When the microwave stops after the set drying time, the current meter will show zero.
- Turn off the frequency converter and conveyor. Remove the dried material and turn off the dehumidifying system.
- If the machine has been working for a long time, to prolong the life of electrical components, wait 10-15 minutes for them to cool before turning off the exhaust fan.
- Press the emergency stop button and turn off the main power switch.
- Temporary Stop Operation
If you need to pause the machine briefly during normal operation, follow these steps: - Turn off all microwaves and stop the frequency converter. The current meters on all microwave chambers should read zero.
- Turn off the exhaust fan and dehumidifying fan.
Restart after temporary stop
- Turn on the exhaust fan and the dehumidifying fan.
- Turn on the microwave and frequency converter to resume normal operation.
Troubleshooting methods for microwave drying machine
| PHENOMENON | REASONS | CLEARING OF FAULT |
| Fans don’t work | 1. The switch is not closed; 2. Poor contact; 3. Fan blade stuck. | Closed circuit breaker Check the fan terminal Change fan |
| Breaker tripping（control box） | 1. Transformer short circuit; 2. Voltage doubler rectifier diode breakdown; 3. Voltage doubler capacitor breakdown. | Change transformer Change diode Change high voltage capacitor |
| No indication on ammeter | 1. Plug don’t contact well; 2. Voltage doubler capacitor or diode circuit magnetrons don’t have high pressure; 3. Transformer bad; 4. Magnetron lamp wire is broken; Magnetron aging; 5. Ammeter bad; 6. Temperature switch is damaged,open circuit; 7. AC contactor line circuit breaker. | Check and plug Change double voltage capacitor or diode Change transformer Change magnetronChange magnetron Change current meter Change temperature switch Change AC contactor |
| Speed motor have a smell and slow | 1. Three phase power supply lack phase; 2. Motor bad. | Cut off power quickly,check reason of lack phase and change motor. |
| Shell charged | 1. Bad grounding; 2. Ground wire fall off. | Check ground wire,should be well-connected,solid connection |
| Sound of ventilation fan is abnormal | 1. Three phase power supply lack phase; 2. Wind leaf met shell. | Check phase,rule out and repair blades |