Abstract: A new and improved discharge system for a spray dryer that permits the immediate exit of dry solids from the chamber of a spray dryer is disclosed. The spray dryer apparatus of the invention comprises a cylindrical drying chamber having a lower conically shaped discharge portion. The liquid or slurry is introduced into the drying chamber in the form of fine droplets which are contacted with a stream of hot gas that evaporates the liquid, leaving residual particles of dry solids. The solids are collected in the discharge portion of the dryer. The latter, i.e., the conical bottom is provided with a series of openings or slots near the bottom discharge outlet. Vacuum means, such as an exhaust fan creates a vacuum in the discharge outlet so that outside air is pulled in through the openings and the air conveys the solids immediately as they are collected. The solids in the stream of air are recovered by means of a gas-solids separator such as a cyclone separator.