Spray Dryer

Spray drying is a process widely used in the industrial route of particle forming and drying. It is suitable for producing powdered, granular or lump solid products from liquid feedstocks such as solutions, emulsions and pumpable suspensions. Where the finished product's particle size distribution, residual moisture content, bulk density and particle shape have to meet precise specifications, spray drying is therefore an ideal process.

In the spray drying process, a liquid feedstock is turned into fine droplets inside a drying chamber and brought into contact with hot air to dry it. Atomization can be carried out with a rotary atomizer or a nozzle atomizer. Evaporation of the droplets can be adjusted as required through temperature and airflow conditions. The dried powder product is discharged continuously from the drying chamber. Operating conditions and dryer design can be selected according to the drying characteristics the product requires and the specifications of the powder.

Every spray drying system comprises a feed pump, atomizer, air heater, air diffuser, drying chamber, and exhaust gas cleaning and dust recovery systems. The quality requirements of the many products that are spray dried — together with their widely differing drying characteristics — determine the choice of atomizer, the appropriate airflow pattern and the drying chamber design.