As a core equipment in the field of food processing, the operating standards of the fruit and vegetable belt dryer directly affect product quality and production efficiency. From equipment debugging to process parameter optimization, standardized processes need to be followed to achieve efficient drying. The following analysis will be conducted from four aspects: preliminary preparation, operation control, process adjustment, and maintenance.

　　1、 Equipment debugging and pre inspection: laying the foundation for safe operation

1. Mechanical system inspection

Before starting, it is necessary to confirm that the conveyor belt is not damaged, the transmission bearings are well lubricated, and the gear mesh clearance meets the standard (error ≤ 0.1mm). A dehydrated vegetable factory once caused material accumulation due to insufficient tension of the mesh belt, resulting in local overheating accidents.

2. Hot air system testing

Check that the direction of the circulating fan is correct and the air pressure is stable within the range of 1500-2000Pa. Verify the heating rate of the heater through a temperature sensor, requiring a heating time of ≤ 15 minutes at the target temperature of 80 ℃.

3. Electrical system calibration

Test the accuracy of the temperature controller, and the error should be controlled within ± 1 ℃. Set the over temperature alarm threshold (usually set temperature+10 ℃) and verify that the emergency stop button response time is less than 0.5 seconds.

　　2、 Operation control: precise parameter matching of material characteristics

1. Coordination between material thickness and mesh belt speed

High moisture content materials (such as carrot slices) are combined with thin-layer paving (thickness ≤ 15mm) and high-speed operation (0.3-0.5m/s), while low moisture content materials (such as mushrooms) can be appropriately increased in paving thickness (20-25mm) and reduced in speed (0.1-0.2m/s).

Step by step temperature control

The initial drying stage temperature is set at 70-80 ℃, the middle stage is raised to 85-95 ℃, and the final drying stage is maintained at 75-85 ℃. A fruit and vegetable processing factory has shortened the drying cycle by 20% and increased the product rehydration ratio by 15% through this strategy.

3. Optimization of airflow organization

Adopting a bidirectional air supply mode, ensuring that the temperature difference between the upper and lower parts of the material layer is ≤ 5 ℃. Regularly clean the dust accumulation on the fins of the heat exchanger to maintain a heat transfer efficiency of over 90%.

　　3、 Dynamic adjustment of process parameters: responding to changes in material characteristics

1. Real time monitoring of moisture content

Install an online moisture meter at the discharge end, which automatically adjusts the hot air temperature or mesh belt speed when the detected value deviates from the target value (such as dehydrated vegetables ≤ 8%).

2. Intelligent compensation for wind speed

Adjust the frequency of the circulating fan through a frequency converter to maintain the wind speed within the range of 2-3m/s. For fragile materials such as strawberry slices, the wind speed can be reduced to 1.5m/s and the drying time can be extended.

3. Waste heat recovery and utilization

Configure plate heat exchangers to recover heat from wet exhaust gas, increasing thermal efficiency to over 75%. A certain enterprise saves over 300 tons of steam consumption annually through this technology.

　　4、 Maintenance and emergency response: ensuring long-term operation of equipment

1. Regular cleaning and lubrication

Clean up residual materials on the mesh belt after daily production, and add high-temperature resistant lubricating grease to the transmission chain every week (working temperature>120 ℃).

2. Periodic replacement of vulnerable parts

The filter should be replaced every 3 months, and the seals should be checked and replaced every 6 months. Establish a spare parts inventory warning mechanism to ensure that the inventory adequacy rate of critical components is ≥ 95%.

3. Handling of abnormal working conditions

When the fan overload alarm occurs, immediately stop the machine and check if the air duct is blocked; If the material is found to be burnt, it is necessary to verify whether the heater temperature sensor is malfunctioning.

The operation of the fruit and vegetable belt dryer requires process adaptation as the core, and through the collaborative optimization of mechanical, thermal, and electrical systems, the goal of reducing energy consumption by more than 20% and increasing product qualification rate to 98% can be achieved. It is recommended that enterprises establish a skill certification system for operators and introduce PLC intelligent control systems to promote the development of drying processes towards precision and energy conservation.