High speed centrifugal spray dryerIt is an advanced drying equipment widely used in industries such as chemical, food, and pharmaceutical. Its core principle is to atomize liquid materials into small droplets through a high-speed rotating centrifugal atomizer, and then quickly exchange heat with hot air to achieve efficient drying.
The equipment mainly consists of a feeding system, atomization system, hot air system, drying tower, feeding system, and control system. During operation, liquid materials are pumped to the atomizer and, under the action of a centrifugal disk rotating at high speed (up to 10000-30000 revolutions per minute), are thrown out and form a uniform group of droplets. These droplets come into full contact with hot air and complete water evaporation in a very short period of time (usually 5-30 seconds), ultimately forming powder or granular products that are discharged from the bottom of the tower. The exhaust gas is treated by a dust removal device before being discharged.
High speed centrifugal spray dryerThe operation steps must strictly follow the specifications to ensure production safety and product quality, as follows:
1、 Preparation before operation
Equipment inspection
Check whether the core components such as the host, fan, heater, and centrifugal atomizer are intact, whether the connecting bolts are tightened, and whether there is any looseness or abnormal wear.
Check whether the piping system (feed pipe, hot air duct, exhaust duct, etc.) is unobstructed, whether there is blockage, leakage or corrosion, and whether the sealing components (such as sealing rings, gaskets) are intact.
Check the electrical system: whether the power cord connection is firm, whether the grounding is reliable, whether the instruments, buttons, and indicator lights on the control panel are normal, and ensure that there are no short circuits or leakage hazards.
Check the centrifugal atomizer: Confirm that the atomizing disc is installed correctly, without deformation, without jamming or abnormal noise during rotation, and that the lubricating oil (or grease) level meets the requirements.
Material preparation
Ensure that the concentration, viscosity, temperature, and other parameters of the material to be dried meet the equipment requirements (different material characteristics need to be matched with corresponding atomization and drying conditions, refer to the equipment manual or process documents for details).
Pre treat the materials (such as filtration and impurity removal) to prevent impurities from entering the equipment, damaging the atomizer, or affecting product purity.
Preparation of auxiliary system
Prepare heat sources (such as steam, electric heating, gas, etc.), ensure stable supply, and ensure that pressure and temperature meet the set values.
Check the cooling water system (if the atomizer uses water cooling) to ensure that the pipeline is unobstructed and the water volume and temperature are normal.
Clean the residual materials in the drying tower, cyclone separator, bag filter and other components to avoid cross contamination.
2、 Power on operation
Activate auxiliary equipment
Turn on the main power, start the induced draft fan (exhaust system), adjust the air damper to the appropriate opening, and create negative pressure in the drying tower (usually set according to process requirements, generally 5-20Pa).
Start the air supply fan (intake system), gradually adjust the intake air volume, and cooperate with the induced draft fan to maintain stable negative pressure inside the tower.
Preheating and drying system
Start the heater and set the inlet air temperature according to the drying requirements of the material (such as the common temperature range of 50-180 ℃ in the food industry, depending on the characteristics of the material).
Wait for the equipment to heat up, and when the inlet air temperature reaches the set value and stabilizes, prepare to start the atomizer and feeding system.
Start atomizer and feed
Start the centrifugal atomizer and adjust the speed to meet the process requirements (the higher the speed, the finer the atomized droplets, and the faster the drying speed, which needs to be set according to the material and product particle size requirements).
Turn on the feed pump (or feed valve) and first feed the atomizer with a small flow rate, observing the atomization effect (ensuring that the droplets are evenly dispersed and there is no splashing or aggregation).
Gradually adjust the feed rate to match the drying heat load (avoiding insufficient drying caused by excessive feed rate or energy waste caused by insufficient feed rate), while closely monitoring the exhaust temperature. By adjusting the feed rate, heating power, or feed rate, stabilize the exhaust temperature within the set range (usually 20-50 ℃ lower than the feed temperature, depending on the material).
3、 Monitoring and adjustment during operation
Parameter monitoring
Real time monitoring of key parameters such as inlet air temperature, outlet air temperature, negative pressure inside the tower, atomizer speed, feed rate, and hot air volume to ensure fluctuations within the process range (deviation generally does not exceed ± 5 ℃ or ± 10Pa).
Observing product status: Regularly sample the product through the sampling port to check its moisture content, particle size, color, flowability, etc. If it does not meet the requirements, adjust the parameters in a timely manner (such as increasing the atomizer speed if the particle size is too coarse, and increasing the inlet air temperature or reducing the feed rate if the moisture content is too high).
exception handling
If there is a sudden increase in the inlet air temperature, it may be due to a heating system malfunction or insufficient air volume. The heating power should be immediately reduced and the inlet air volume should be increased. If necessary, the feeding should be paused.
If the outlet air temperature suddenly drops, it may be due to excessive feeding or insufficient heating. The feeding amount should be reduced or the heating power should be increased.
If there is abnormal noise or severe vibration in the atomizer, it is necessary to immediately stop the machine for inspection, eliminate problems such as unbalanced atomization disc and bearing wear, and avoid equipment damage.
If wall sticking occurs inside the tower (material adhering to the tower wall), the inlet air temperature can be appropriately increased, the atomization angle can be adjusted, or the tower wall vibration device (if any) can be activated for cleaning.
4、 Shutdown operation
Stop feeding and heating
First, turn off the feed pump, stop feeding the atomizer, and continue to keep the atomizer running. Rinse the feed pipeline and atomizer with clean water or solvent (depending on the characteristics of the material) to remove residual materials (to avoid material drying up and blockage inside the atomizer).
Turn off the heater, stop heating, but keep the supply fan, induced draft fan, and atomizer running, and use cold air to blow and cool the inside of the equipment.
Stop atomizer and fan
When the temperature inside the tower drops below 60 ℃ (to avoid residual material deterioration or spontaneous combustion caused by waste heat), turn off the atomizer.
After the atomizer stops, turn off the air supply fan and induced draft fan in sequence.
Cleaning and Inspection
After the equipment cools down, open the maintenance doors of the drying tower, cyclone separator, dust collector and other components to clean up residual products and materials, ensuring internal cleanliness (especially in corners and sealed areas).
Check for wear or blockage of components such as atomizers, feed pumps, and pipelines, and promptly clean or replace vulnerable parts (such as atomizing discs and gaskets).
Turn off the main power and organize operation records (such as operating parameters, product quality, abnormal situations, etc.).