Flash dryers are used to dry efficiently those materials that can be transported pneumatically in large volume. During this conveying operation, small solid particles can be dried by pre heating the carrier air or gas to such an extent that it act as a drying medium. These types of dryers always operate in a co-current manner, and the drying takes place in a very short period of time. Flash dryers are probably the most suitable forms of atmospheric pressure continuous direct dryers. These dryers are most suitable for drying wet materials with a moisture content is in the form of recoverable solvents.