The spray drying process is older than might commonly be imagined.   Earliest descriptions date from 1860 with the first patented design  recorded in 1872. The basic idea of spray drying is the production of highly  dispersed powders from a fluid feed by evaporating the solvent. This is  achieved by mixing a heated gas with an atomized (sprayed) fluid of high  surface-to-mass ratio droplets, ideally of equal size, within a vessel (drying  chamber), causing the solvent to evaporate uniformly and quickly through direct  contact.

 Spray drying can be used in a wide range of applications where the  production of a free-flowing powder is required. This method of dehydration has  become the most successful one in the following areas:
 Pharmaceuticals
 Bone and  tooth amalgams
 Beverages
 Flavours,  colourings and plant extracts
 Milk and  egg products
 Plastics,  polymers and resins
 Soaps  and detergents
 Textiles  and many more

Almost all other methods of drying, including use of ovens, freeze dryers  or rotary evaporators, produce a mass of material requiring further processing  (e.g. grinding and filtering) therefore, producing particles of irregular size  and shape. Spray drying on the other hand, offers a very flexible control over  powder particle properties such as density, size, flow characteristics and  moisture content.

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