The working process of a pressure spray dryer is as follows: Liquid feed is input under high pressure through a pneumatic diaphragm pump, spraying out as a mist of droplets. The droplets then descend in parallel with hot air. Most of the powder particles are collected at the bottom discharge port. Waste gas and fine powder are separated by a cyclone separator. The waste gas is discharged by an exhaust fan, and the powder is collected by a powder collection cylinder located below the cyclone separator. A secondary dust removal device can also be installed at the fan outlet. The recovery rate is 96%-98%.
I. Applications of Pressure Spray Drying
Chemicals: Organic catalysts, resins, synthetic detergents, oils, ammonium sulfate, dyes, dye intermediates, white carbon black, graphite, ammonium phosphate, etc.
Food: Amino acids and similar substances, seasonings, proteins, starches, dairy products, coffee extracts, fishmeal, meat extract, etc.
Pharmaceuticals: Traditional Chinese medicine, pesticides, antibiotics, pharmaceutical powders, etc.
Ceramics: Magnesium oxide, kaolin, various metal oxides, dolomite, etc.
II. Daily Operation Procedures for Pressure Spray Dryers
During prolonged operation or improper operation, material buildup may occur inside some parts of the pressure spray dryer, affecting normal operation. In this case, operation must be stopped for cleaning. To clean the material buildup inside the drying tower, open the cleaning door and use a long-handled broom to sweep away the material at the bottom of the funnel. Open the discharge valve and rinse the inside of the tower with tap water. Similarly, to remove dust from the cyclone separator, open the cyclone separator, sweep away the material with a broom, and rinse with water if necessary. For cleaning the bag filter, turn on the control switch and tap continuously, then open the cleaning door and tap the bag filter. Finally, replace the filter bag. For cleaning the slurry pipeline system, open the drain valve of the bidirectional filter, clean the filter screen and pipeline, then turn on the feed pump and use water instead of feed to clean the pump pipe, pressure stabilizer, and pipelines.
After a period of operation, necessary inspections and maintenance of the spray granulation dryer are required. For the feeding system, inspect filters, pipes, valves, nozzles, etc., for blockages, clean them regularly, and check nozzle wear for timely replacement. Check the feed pump for oil leaks, normal pressure, and normal oil level. For the blower, check the shaft and bearings for insufficient oil and overheating, and for vibration and noise; clean the fan blades and balance them if necessary. For the heater, check the heat pipes for normal operation, and clean the filters at the oil pipes, oil pump, and oil nozzles if necessary. Additionally, pay attention to whether each motor is overheating, vibrating, or making abnormal noises, and check the instruments and electrical components in the control cabinet for proper functioning.
