Dryer & Cooler types
Dryers are used to produce dry solids. They can be classified in different ways. Whether they are continuous or batch, whether the product is heated by hot air (convection) or by heated surfaces (contact), whether atmospheric or vacuum.
Batch versus Continuous: determined by the production capacity and the drying characteristics of the product. Fast drying products are better served by continuous systems with residence times up to 30 minutes. Slow drying products often are a function of diffusion of liquids from the product and usually are dried in batch.
Contact versus Convection: convection dryers use hot air to convey heat to the product and liquid. With contact dryers the metal surfaces are heated by heating medium while the hot metal transfers the heat into the product.
Atmospheric versus Batch: heat sensitive products are dried under vacuum to allow liquid boiling at lower temperatures and avoid overheating of product.
We will limit us here to describe the dryers of our suppliers.