Spray dryer is a device that uses spray technology to instantly dry liquid materials into powder. It is widely used in food, medicine, chemical industry and other industries. Daily maintenance and upkeep can effectively extend equipment life, ensure drying efficiency and product quality. Specific measures are as follows:
Equipment appearance and connection
Check the body, pipelines, and valves for any damage or leakage, especially the sealing of the interfaces of the feed pipe, compressed air pipe, and steam pipe.
Confirm whether all fasteners (bolts, nuts) are loose, especially the fixing of rotating parts such as atomizers, fans, pumps, etc.
Key System Status
Feeding systemCheck the liquid level of the material storage tank, whether there is blockage or corrosion in the pipeline, and whether the motor rotation and lubricating oil level of the feed pump (such as screw pump, centrifugal pump) are normal.
Atomization systemCentrifugal atomizers require checking the balance of the turntable and the temperature of the motor bearings; The pressure atomizer needs to confirm the cleanliness of the nozzle and the stability of the high-pressure pump pressure; The air flow atomizer needs to check the compressed air pressure and pipeline sealing.
Heating and ventilation systemCheck the calibration of temperature control instruments for heaters (electric heating, steam heating), the cleanliness of impellers and belt tightness of fans (induced draft fans, supply fans), and whether filters (air filters, dust filters) are clogged.
Parameter monitoring and adjustment
Real time recording of parameters such as inlet temperature, outlet temperature, liquid flow rate, atomization pressure (or speed), vacuum degree (if equipped with a vacuum system), etc., to ensure that they are within the process range (such as the inlet temperature in the food industry usually being 180-220 ℃ and the outlet temperature being 70-90 ℃).
If there is a sudden increase in exhaust temperature, it may be due to insufficient supply of feed liquid, and the feed pump or pipeline should be stopped and checked in a timely manner; If the temperature drops sharply, it may be due to blockage of the atomizer or heating failure, which requires urgent handling.
exception handling
When abnormal equipment noise (such as the sound of worn bearings in fans and atomizers), excessive vibration (possibly due to unbalanced impellers or loose feet), or leakage (liquid or steam) is found, the machine should be stopped immediately for troubleshooting to prevent the fault from expanding.
To prevent the liquid from sticking to the wall in the drying tower: If there is too much material on the wall, the tower wall vibration device (such as a pneumatic hammer) can be activated or the atomization angle can be adjusted. If necessary, the feeding can be paused and the inner wall can be blown with hot air.
Comprehensive cleaning
Inside the drying towerRinse the tower wall, atomizer, and guide plate with clean water or specialized cleaning agents (such as alkaline solution to remove grease and acidic solution to remove scale) to avoid residual material clumping (especially high sugar and high protein materials that are prone to bacterial growth).
auxiliary equipmentClean the liquid storage tank, pipeline, and filter screen to prevent residual liquid from deteriorating; The centrifugal atomizer needs to dismantle the turntable and wipe it with a soft cloth (to avoid scratches), and the pressure nozzle needs to clear the aperture (which can be cleaned with fine steel wire or ultrasonic waves).
Ventilation and heating componentsClean the air filter element (can be washed with water or replaced), check if there is any dust accumulation on the surface of the heater (affecting heat transfer efficiency), and remove the dust attached to the fan impeller (to avoid impeller imbalance).
Component inspection and maintenance
Rotating components: Add lubricating oil (grease) to the atomizer motor, fan bearings, pump bearings, etc., and replace them periodically according to the instructions (such as changing the lubricating oil every 500 hours of operation).
Seals: Check whether the sealing rings (such as silicone rings and PTFE gaskets) of the feed pipe and steam pipe are aging, and replace them in a timely manner to prevent leakage.
Electrical system: Clean the dust inside the control cabinet (blow with compressed air), check whether the wiring terminals are loose, and whether the temperature control sensors, pressure gauges, and other instruments are sensitive.
Weekly maintenance
Check the wear of the atomizer turntable or nozzle (such as whether there are gaps on the edge of the centrifugal turntable and whether the nozzle aperture has increased), and replace spare parts if necessary.
Test the effectiveness of safety devices (such as over temperature alarm, overload protection, emergency stop button) to ensure immediate shutdown when triggered.
Monthly maintenance
Calibrate key instruments (thermometers, pressure gauges, flow meters) to ensure measurement accuracy.
Check the transmission components: the tension of the fan belt (with a deflection of 10-15mm), the temperature rise of the motor bearing (not exceeding 40 ℃ during operation), and replace the belt or bearing if necessary.
Annual maintenance
Perform anti-corrosion treatment on the inner walls and pipelines of the drying tower (such as spraying high-temperature resistant coatings), and inspect the welds for corrosion and leakage.
Comprehensively inspect power equipment such as motors and pumps, replace aging wires and cables, evaluate the service life of core components such as atomizer motors and high-pressure pumps, and reserve vulnerable parts in advance such as nozzles, bearings, and seals.
Corrosive materialsIf dealing with acidic and alkaline materials, stainless steel (such as 316L) or titanium components should be selected, and corrosion should be checked regularly to shorten maintenance cycles.
Flammable and explosive materialsIf the solvent based liquid (containing ethanol and acetone) is used, it is necessary to ensure that the equipment is grounded (anti-static), and explosion-proof motors and instruments are used to avoid the danger caused by sparks.
Seasonal maintenanceAfter shutting down in winter, it is necessary to drain the residual water in the pipes (especially steam pipes and cooling water pipes) to prevent freezing and cracking; Pay attention to motor heat dissipation in summer and clean the filter of the cooling fan.
Normal routine maintenance can significantly reduce the failure rate of spray dryer, ensure product purity (reduce cross contamination) and production efficiency, and extend the service life of equipment (usually up to 8-10 years, and replace core components such as atomizer for 3-5 years).