Flash Dryers and Coolers Flash Dryer

The pneumatic system used to drive off free moisture in seconds.

Elevated drying temperatures can be used with many products since the flashing off of surface moisture instantly cools the drying gas without appreciably increasing the product temperature which may damage its quality.

Flash Drying Process

Wet material is dispersed into a stream of heated air (or gas) which conveys it through a drying duct. Using the heat from the airstream, the material dries as it is conveyed. Product is separated using cyclones, and/or bag filters. Typically, cyclones are followed by scrubbers or bag filters for final cleaning of the exhaust gases to meet current emission requirements. 

For even greater thermal efficiency and where inertization is required, recycling of exhaust gases can be used. This partial gas recycle (PGR) configuration can be implemented on all our airstream drying systems as well as retrofitted on customer's existing drying operations. 

Flash dryers have been used to dry products in many industries including agrifood, chemical, mineral. A broad range of feed materials including powders, cakes, granules, flakes, pastes, gels, and slurries can be processed. For slurries, pastes, or sticky materials, backmixing of the wet feed with a portion of dry product to produce a suitable conditioned material is required.

Pneumatic Cooler Conveyor

Pneumatic coolers are a simple and reliable method of cooling and conveying dried product. In many instances ambient air will achieve the desired cooling duty. Where required, greater cooling capacity and a finer degree of control can be achieved with conditioned air at a controlled humidity and temperature.

 

Features

  • Short residence time
  • A buffer hopper or back-mixing system if required
  • Can be designed for open circuit, partial gas recycle and SSD™
  • Can be designed for operation in an inert atmosphere
  • Simple system with few moving parts

Benefits

  • Promotes product quality
  • Flexibility to work with different dewatering systems and to enable use with friable and non-friable wet feeds
  • Enables energy savings and system integration
  • Suitable for operation with solvent and recovery thereof
  • Cost effective and reliable with low maintenance and cleaning requirements - good for regular grade changes

Process Flow Diagram

Flash drying process diagram