The Multistage Airheater is a patent pending product that is used for heating circulating air in the pneumatic fiber dryers.
Multistage air heater is a vertical tubular heat exchanger, where the circulating air flows downwards on the tube side and The shell side is divided into two or three compartments through intermediate tube sheets. This construction makes it possible to use steams with different pressures in a single piece of equipment.
The steam with lowest pressure is connected to the uppermost compartment and the steam with highest pressure to the lowest compartment. This arrangement minimizes the risk of fibers being darkened on the hot tube sheet, because the fibers can only be contacted with the coldest tube sheet of the heater.
Air Heaters can be equipped with an internal fiber cleaning system to avoid the risk of fiber accumulation on the tube sheet.