Spray drying is a method of producing a dry powder from a liquid or slurry by rapidly drying with a hot air. The feed is pumped to a nozzle/s or rotary atomizer at high pressure. The atomizer or nozzle atomizes the pumped liquid into very fine droplets of about 30 to 100 microns in size. At the same time hot air is passed through air distributor into drying chamber. This hot air comes in contact with the atomized feed particles and removes moisture. The dry powder drops down at bottom cone of chamber and is collected. Air leaves the drying chamber and is passed through cyclone and or bag filter / wet scrubber. Powder not trapped in chamber is collected at the outlet of cyclone separator. Very fine powder escaping cyclone is collected in Bag Filter or Wet Scrubber. Spray Dryers can be of co-current, counter current, tower or with Fluid Bed Cooler type. Also the design of chamber varies according to products and operating temperatures. Spray Dryers are used in food processing, chemicals, ceramic and pharmaceutical sectors. If product is oxygen sensitive or solvent being evaporated is flammable, then Closed Loop Spray Dryer with nitrogen gas is used.