Ten Key Principles of Spray Drying, an Important Drying Equipment for Plant Extract Powder
Each spray drying equipment consists of seven systems: feeding pump, atomizer, air heater, air distributor, drying chamber, dust recovery system, and exhaust gas cleaning system. To truly understand spray drying, it is necessary to grasp the following ten key principles: Atomization: Using an atomizer to disperse the liquid material (which can be a solution, emulsion, suspension, or melt) into uniform droplets. Contact between droplets and hot air: Hot air, distributed evenly by the hot air distributor, enters the drying chamber, where it mixes thoroughly with the droplets and moves according to certain rules (the contact between air and droplets can be concurrent, countercurrent, or mixed flow). Drying process: Due to their large surface area and significant “gradient” in temperature and humidity compared to the hot air, these droplets enhance the process of heat and mass transfer, causing the water content within them to rapidly vaporize and evaporate (typical...