A compact freeze dryer removes a liquid from a bulk powder product. The freeze dryer utilizes a single cryogenic vessel for both (1) freezing the liquid contained in the bulk product, and (2) condensing vapor resulting from sublimating the frozen liquid. A vacuum pump is connected to the cryogenic vessel for drawing a vacuum in the cryogenic vessel and in a drying vessel. Vapor resulting from subliming the frozen liquid in the drying vessel is drawn into the cryogenic vessel and condensed.