Drying Technology

Agitated Thin Film Dryer
Agitated thin film dryers are used for continuous drying of heat sensitive products with total solvent recovery. This is ideal for drying pharmaceuticals, bulk drugs and intermediates, organic and inorganic salts.

Agitated Thin Film Dryer (ATFD) is the final stage equipment in Zero Liquid Discharge plant. Concentrated liquid is spread over the wall of jacket vessel to form thin film. Due to film technology high heat transfer coefficient is achieved and liquid gets evaporated. Powered product is collected from the bottom of the ATFD.

Scrapping blades are provided to scrap the powder from wall of jacket to keep surface area ready for new film evaporation. Evaporated vapors are condensed in separate condenser for solvent recovery.

Spray Dryer

Spray drying is a method of producing a dry powder from a liquid or slurry by rapidly drying with a hot gas. This is the preferred method of drying of many thermally-sensitive materials such as foods and pharmaceuticals. Spray Dryer takes a liquid stream and separates the solute or suspension as a solid and the solvent into a vapor. The solid is usually collected in a drum or cyclone. The liquid input stream is sprayed through a nozzle into a hot vapor stream and vaporized.

Solids form as moisture quickly leaves the droplets. A nozzle is usually used to make the droplets as small as possible.

Applications of Spray Dryers

  • Food and beverages: Production of milk powder, coffee, tea
  • Pharmaceutical: Antibiotics, medical Ingredients
  • Industrial: paints, ceramic materials


  • Effective for viscous, fibrous and crystalline products
  • High heat transfer rates due to film boiling
  • Compact design
  • Complete solvent recovery
  • Easy to maintain