The presence of the "manifold" or "internal classifier" in the Ring drying systems are what differentiates them from the Flash dryer. The manifolds use the centrifugal forces created through passing a product containing air-stream around a curve to concentrate the product into a moving layer. Adjustable splitter blades are used to cut this layer and return the heavier, semi-dried materials back to the dryer for another pass through the system while the lighter, drier products exit the dryers and proceed to the product collection systems.