Spray Dryers
Spray dryers take a material, such as wet sludge or wet powder, and spin it centrifugally before directing a line of spray of the material into a drying chamber. The material is then rapidly dried. Spray dryers are also commonly called dispersion dryers.
All spray dryers contain an air heater, atomizer, feed pump, air disperser, drying chamber and cleaning system. The evaporation rate and the necessary size distribution of a product determine how much air is needed, which then affects the size and cost of most system components. As a result, these are the most important factors when designing a spray dryer.
Spray drying is often used when the product must meet exact requirements in terms of particle size distribution, particle shape, bulk density, and residual moisture content. Applications for spray dryers include food flavorings, pigments, industrial chemicals, ceramic products, dyestuffs, catalysts, detergents, salts and many more. Advantages of spray drying include particle size control, enhancing flow properties of dry solids, evaporative cooling, corrosion reduction, and short residence.