When using a spray dryer, the core focus is on three dimensions: safe operation, product quality control, and equipment protection. Special attention must be paid to key aspects such as operating procedures, parameter monitoring, and compatibility with material characteristics.
I. Safe Operation: Eliminating Risks and Hazards
Strictly adhere to the start-up and shutdown sequence: Ventilation must be prioritized before heating, followed by material feeding. Shutdown must be completed by stopping material feeding first, then stopping heating, and finally stopping the fan. This prevents accidents caused by high-temperature dry burning or material residue.
Do not open the drying tower door or maintenance ports while the equipment is running to prevent burns or inhalation risks from high-temperature airflow or dust. If maintenance is required, the power must be disconnected first, and the equipment must be ensured to have cooled down.
When handling flammable and explosive materials (such as certain chemical raw materials), anti-static measures must be taken to ensure the equipment grounding resistance is less than 4Ω. Smoking and open flames are strictly prohibited around the equipment.
Operators must wear protective equipment, including dust masks, safety glasses, and high-temperature resistant gloves. Protective clothing is also required when handling corrosive materials.
II. Parameter Monitoring: Ensuring Product and Equipment Stability
Monitor inlet and outlet air temperatures in real time. These temperatures must be matched to the material characteristics (e.g., inlet air temperature should be lowered for heat-sensitive materials). If the outlet air temperature fluctuates abnormally (too high or too low), adjust the feed rate promptly to prevent the finished product from becoming too dry, clumping, or having excessive moisture content.
Control the negative pressure within the equipment, typically maintaining it between -50Pa and -150Pa. Excessive negative pressure can attract external impurities, while insufficient negative pressure may cause dust leakage, affecting the workshop environment and product purity.
Monitor the atomizer status. For centrifugal atomizers, check if the rotation speed meets the standard. For pressure atomizers, ensure the nozzles are not clogged and the pressure is stable. If uneven atomization occurs, immediately stop the machine for cleaning or replacement of parts to avoid affecting the drying effect.
III. Material and Equipment Protection: Extending Lifespan and Ensuring Quality
Proper material pretreatment is essential. The feed solution must be filtered to remove impurities and particles to prevent nozzle clogging or atomizer wear. Simultaneously, the feed solution concentration should be controlled (typically 10%-50%). Excessive concentration leads to poor atomization, while insufficient concentration increases energy consumption.
Regular equipment cleaning is crucial. After each use, the feed pipe, atomizer, drying tower inner wall, and cyclone separator should be cleaned with water or a suitable solvent to prevent material residue from clumping, affecting the quality of subsequent batches or corroding the equipment.
Daily equipment maintenance is vital. Weekly checks of atomizer bearing lubrication, monthly calibration of temperature and pressure gauges, and quarterly nozzle disassembly and cleaning are necessary to ensure component flexibility, accurate data, and extended equipment lifespan.