GB849329A - Improvements in or relating to the treatment, for example, drying of materials in fluidised beds - Google Patents

Abstract

849,329. Drying threads, fabrics etc.; fluidized beds for heating. sheet or filamentary materials. BRITISH RAYON RESEARCH ASSOCIATION. Feb, 8, 1957 [Feb. 18, 1956; Aug. 21, 1956], Nos. 25811/59 and 25812/59. Divided out of 838,784. Classes 34(1) and 64(2) Material in thread or sheet form is dried &c. by passage through a hot fluidized bed 19, Fig. 1, of solid particles in a container 11, the material entering the container through an aperture 17, sealed by a rigid angle 21 and a flexible strip 21b of phosphor bronze supported by a rigid angle 21a, and passing through an aperture 14 in a perforate division plate 11b supporting the bed, said aperture 14 being sealed by particles 18 of larger size than the particles comprising the bed and enclosed by partitions 15 having slots 16. The particles comprising the bed and the seal may consist of glass balls having diameters of 0.5 mm. and 3 mm. respectively. The bed is fluidized by compressed air admitted through pipes 13 to the space beneath the plate 11b. Small particles from the bed entering the enclosure formed by the partitions 15 through the space between their upper portions may return to the bed through the slots 15. In a modification, the aperture in the division plate is sealed by large particles 18, Fig. 2, filling the space beneath the division plates 20 and underlying the fluidized bed. The aperture between the plates 20 may be 0.5 in. wide. In another arrangement, the aperture in the bottom of the container is sealed by a pair of rollers 22, Fig. 5, and flexible strips 23. The stentoring means for conveying fabric sheet through the fluidized bed are similar to those described in Specification 838,784. Compressed air may be directed from within the stentor chain guides through the clearance between the slots in the guides and the stentor plates to prevent the entry of bed particles into the guides. Specifications 773,598, 800,091 and 817,992 also are referred to.