An Agitated Thin Film Dryer is utilised to generate a granular substance with high flowability from a slurry or solution-type feed. It is extensively employed in the pharmaceutical, chemical, and food sectors. These are employed in circumstances where traditional dryers/evaporators are incapable of managing the solutions.
An Agitated Thin Film Dryer is a type of drying equipment that utilises a scraped heat exchanger to carry out a continuous drying operation. This equipment is designed to function under decreased pressure, making it suited for drying heat sensitive materials. The Agitated Thin Film Dryer comprises two primary components: the drying chamber equipped with a heating jacket, and the rotor featuring fixed blades.
Multi-effect evaporators are utilised in industries across the globe to concentrate or dewater industrial waste liquids or RO reject slurries with a maximum TDS of 400000 to 500000 ppm. Subsequently, this mixture, which is challenging to manage, can be effortlessly transformed into solid salts and purified water by utilising AGS's exceptionally effective ATFDs and surface condensers.
The operating principle of an agitated thin film dryer involves the use of a thin film of material that is agitated to enhance heat transfer and drying efficiency.
The Agitated Thin Film Dryer features a vertically-oriented design, with a Rotor that rotates within a precisely manufactured jacketed shell. The feed is transformed into a thin layer, which is vigorously stirred as a result of the high-speed rotor's movement. A distribution ring located on the rotor ensures the uniform dispersion of the liquid along the outside edge. The thickness over the heat transfer surface ranges from 0.5 to 0.6 mm. The feed material undergoes transitions from a slurry state to a paste state and then to a wet powder state, before ultimately emerging as a dry powder.
Another crucial function of the rotor is to maintain the stability of the liquid coating on the heating surface during high rates of evaporation. This facilitates evaporation in the region of nucleate boiling without the occurrence of film rupture. Simultaneously, the liquid layer is forced against the heating surface due to the centrifugal force. This prevents the occurrence of the detrimental phenomenon known as unfavourable evaporation mode, wherein a layer of vapour is created beneath the liquid sheet, resulting in insulation. The Agitated Thin Film Dryer allows for the achievement of extraordinarily high specific evaporation rates due to its operating principle.