ANDRITZ - Model BDC - Belt Drying System
The ANDRITZ SEPARATION belt dryer/cooler BDC is available with gas-, oil-, or steam heating and can be applied for bulk material, food, or chemical products. The drying of the product takes place on a ventilated conveyor belt. Depending on the type of product we can offer either a single-belt dryer or multi-belt dryer.
The BDC belt dryer is a continuous convective belt dryer. A well-ventilated layer of product is put on a wire mesh or perforated plate belt conveyor and conveyed continuously through drying chambers. In these chambers, circulating air fans blow hot air through the product vertically. In this process, the circulating air is reheated after each product flow by the heat exchangers integrated into the dryer.
The amount of air required to discharge the exhaust vapor from the belt dryer is sucked in by a radial fan and fed to the appropriate zones of the belt dryer. Due to the arrangement of the air inlet and outlet ducts to and from the appropriate zones, the drying air is passed repeatedly through the product layer until it has the optimum vapor content before leaving the dryer.
ANDRITZ SEPARATION belt drying or conveyor drying systems are used in the chemical and pharmaceutical industries, in food and stimulants, and for dyes and pigments. The belt dryer is suitable for drying free-flowing, crumbly, crystalline, and lumpy products, as well as malleable pastes.
- Easy maintenance and easy- clean options with simple and efficient access to all internal components
- Easy operation with a fully automatic control system
- Plants can be built in full compliance with ATEX safety regulations
- High thermal efficiency due to the integrated air circulation fans, thereby optimizing the exhaust air volume and heat recovery from the dryer exhaust
- Good adaptation of the temperature profile to the drying behavior of different product qualities
- Capacity from about 200 kg up to 4 tph water evaporation per drying plant
The ANDRITZ SEPARATION BDC belt dryer has a modular design, with band widths of 1-3 m and a drying belt-surface of about 6 to more than 100 m2.
Type BDC-S (Single-Belt Dryer):
Products that tend to generate dust and thus cannot be relocated are dried on a single belt. In this process, optimum drying can be achieved by reversing the direction of air flow through the product.
The ANDRITZ SEPARATION multi-stage dryer or the dryer multi-band (3- or 5-band) can be used for products that are insensitive to the transfer from belt to belt. Wet agglomerate can be disintegrated during the transfer from belt to belt. In a multi-stage dryer, the temperature profile can be adapted directly to the drying process of the respective product.
Large throughput quantities with a long residence time can be dried with the multi-belt dryer. The dryer is heated either internally or in an external air handling unit.
Viscous or pasty products, which cannot be associated with an extruder or granulator in a well-ventilated layer, are dried on a contact belt dryer. Here, the product is placed on a PTFE coated strip and conveyed via contact hotplates. Steam or thermal oil is used for heating purposes (up to 260 °C).
Vapors emerging from the product are absorbed by hot air that is directed above the product layer and discharged continuously.