ABSTRACT
This chapter provides a summary of the basics of the spray drying process, its applications, principal components, and ancillaries. Existing spray drying systems provide various forms of the dry product—from fine powders to granules. Generally the wheel atomizer produces a spray of high homogeneity within a wide range of mean droplet size. The product specifications are almost always determined from small-scale tests in an experimental spray dryer. Sometimes they are available from the literature. In a spray drying process, high flow rates of drying air are generally obtained by the use of centrifugal fans. The air carrying fine particles flows through a venturi; at the throat of the scrubber water is injected to form a spray. The semidried powder is deposited on a moving belt situated at the bottom of the primary spray chamber. A gastight closed-cycle spray dryer with nitrogen as the drying medium may be used in such cases.
