National's Multistage Dryers
Source: National Drying Machinery Company
This design incorporates a series of single-stage, multizone units
This design incorporates a series of single-stage, multizone units. It is ideal for products with a high incoming moisture content, which would benefit from reorientation by transferring between conveyor belts at the ideal time in their drying cycle.
The system normally consists of two to three stages, but can be designed with more. Product bed depth and air flow vary between stages based on the product's drying curve. A series of mouth curtains, zone partitions and tunnel seals creates discrete zones, sealing both above and below the conveyor. These discrete zones allow both air flow and temperature to be independently altered to maintain proper process parameters, even with seasonal or varietal product changes.
This design provides economic use of space at high production rates, and can also be expanded as processing capacity requirements increase.
National Drying Machinery Company, 2190 Hornig Road, Philadelphia, PA 19116. Tel: 215-464-6070; Fax: 215-464-4096.