DEVICE FOR COATING PARTICLES

摘要

The invention relates to a device for coating particles (10), comprising a container (12) with a perforated flow contact floor (14) through which an upwardly-flowing process gas (15) can be delivered; at least one ascending tube (24), which is located in the container at a distance from the flow contact floor, whose top end is open to the container, and in whose bottom end a spray nozzle (18) for spraying coating material into the ascending tube is arranged. A coating area (32) is formed inside the ascending tube and a feedback area (37) is formed outside said ascending tube. Means for delivering a supporting gas (62) are provided in or on the container near the perforated flow contact floor, these means guiding in a supporting gas flow in the direction of the gap with at least one flow component that is oriented inwards, sideways, in order to form a sliding gas layer and to transport the particles between the feedback area and the coating area in a directed particle flow. In addition or alternatively, constructional shaping means (22), (120) are situated in the bottom area of the container, said means forming a transition channel between the feedback area and the coating area with essentially constant peripheral surfaces.