Abstract: To permit the output of a vertical fluidizing-cell column to be increased, its cross-sectional area to be enlarged, and the installation of plates in the column to be simplified, the plates are made conical or pyramidal with their concave and convex sides alternately directed upwardly. The plates have central openings for the passage of one stream of material, and are mounted in the column with peripheral passages for another stream of material. Preferably the plates are movable relative to each other and have movable center pieces variably closing some of the central openings for varying the operation of the column.