Patent ID: 7651714

Claim:
A method of drying an aqueous whey permeate slurry comprising at least about 78% solids, including at least about 50% lactose and having an equilibrium of lactose in solution and lactose in crystalline form; the method comprising the steps of: providing an air-lift dryer, including an enclosed drying chamber having an atomizing inlet for introducing atomized whey permeate into the enclosed drying chamber; the enclosed drying chamber having an upper portion and a lower portion, a primary air inlet and an exhaust air outlet; the atomizing inlet and the primary air inlet being located in the lower portion; and introducing atomized whey permeate into the enclosed drying chamber via the atomizing inlet with sufficient fluid pressure to drive atomized whey permeate upward within the enclosed drying chamber in a direction at least partially in opposition to a gravitational force acting on the atomized whey permeate.