A process dryer is an air dryer technology which is utilized to take out moisture or liquids from continuous sheets, parts, powders, bulk solids or other liquids by sublimation or evaporation. A product air dryer could be broken up within 2 primary kinds: indirect and direct. The direct dryers convectively heat products via direct contact using gas, heated air or some combusted gas product. The indirect dryers conductively heat products via contact with the heated wall. A few of the more common process dryers which an air dryer process plant utilizes includes:
The air bars, that make dispersed drying air, as well as floatation dryers which utilize a sequence of louvers or air bars to gently dry and support webs of materials that are fragile.
The hot air impingement dryers utilize blasts of hot air in order to convectively dry moving boards, webs or other huge materials of bulk.
The belt conveyor dryers utilize a mesh or perforated belt in order to transfer feed materials via the dryer. The heated air will be passed through and under, or through and over the product bed and belt prior to being re-circulated and reheated.
The chamber-type dryers will consist of the heated chamber which is normally heated up to a higher temperature than any other air dryer.
The disc dryers include units that are drum shaped that are filled with series heated discs. Air flow or disc motion is utilized to move the bulk material or powders through a dryer.
Within fluidized bed dryers, the bed of material will be fluidized through air flow or vibration. Powder will be then dried by way of heating directly the combusted gas flow or hot air or via contact with surfaces that are heated.
The suction drum dryers are made up of a sequence of perforated drums or cylinders with a vacuum that is internal. Sheet or web materials will be held against a drum by the suction or vacuum that is generated while the fan draws in air from the inside of a drum. The suction will hold the material to the drum's surface allowing air to pass through a material that is being dried. A part of the drum at the transfer will have no suction and will allow the material to transfer to the next drum without any interference.