Verfahren und Vorrichtung zur Wirbelschichtbehandlung,insbesondere -trocknung von aus losen Teilchen oder Stuecken bestehenden Materialien

1,235,235. Treating food; treating seeds with gases. D. F. FARKAS and M. E. LAZAR. 28 Feb., 1969 [7 March, 1968], No. 11008/69. Headings A2D and A2Q. [Also in Division F4] Particulate material is treated with a gas by introducing it into perforated basket 5, rotating the basket to apply centrifugal force to the material, and directing a stream of gas via inlet 2 through the mass of material in a direction counter to the centrifugal force, the velocity of the gas stream being sufficiently high to cause the individual particles actively to tumble about within the mass, but not so high as to eject particles from the mass before they have undergone a predetermined treatment. The velocity of the gas stream may be sufficiently high to fluidize the mass of material. The process is applicable to drying and dehydrating foods, e.g. peas, beans, other vegetables, fruit, meat, yeast, bones, feathers, wool or cotton, puffing wheat, rice, corn, potatoes and fruit, roasting coffee, cooking or blanching foods, cooling and freezing foods, and reacting solids with gases. Smoke or sulphur dioxide may be added to the chamber. In a continuous process, e.g. drying, the material is introduced at a desired rate by compressed air through inlet 15 and is only ejected into chamber 17 when its density has been sufficiently reduced by drying.