The principle of spray drying method:
After the air is filtered and heated, it enters the air distributor on the top of the dryer, and the hot air enters the drying chamber evenly in a spiral shape. The material liquid passes through the high-speed centrifugal atomizer or high-pressure atomizer on the top of the tower body, and sprays into very fine misty liquid beads, which can be dried into finished products in a very short time in co-current contact with air. The finished product is output from the cyclone separator at the bottom of the drying tower, the fine dust material is collected by the bag filter, and the exhaust gas is evacuated by the fan.
Characteristics of spray drying
1. The drying speed is fast, and the surface area of the material liquid is greatly increased after atomization. In the hot air flow, 95%-98% of the water can be evaporated instantly, and the drying time is only a few seconds;
2. Suitable for drying heat sensitive materials;
3. Wide range of application: According to the characteristics of the material, it can be used for hot air drying, centrifugal granulation and cold air granulation;
4.Since the drying process is completed in an instant, the product has good dispersibility, fluidity and solubility;
5. Simplified production process and convenient operation and control. Spray drying is usually used for solutions with a solid content of less than 60%. After drying, there is no need to pulverize and screen, which reduces the production process and simplifies the production process. For the product's particle size, bulk density, and moisture content, within a certain range, the operating conditions can be changed for adjustment, and the control and management are very convenient;
6. In order to prevent the material from being polluted and prolong the life of the equipment, all parts in contact with the material can be made of stainless steel.
Because the spray dryer can make the solution or suspension into a uniform powder product directly, it is widely used in the food industry, especially in the plant extraction industry, such as Saw Palmetto Berry Powder , Aloe Vera Gel Powder, Cinnamon Bark Powder, etc.