Patent GB-1427412-A (GB)
Title: Apparatus for contacting one substance with another substance
IPC: F28C3/00
Filed: 1973-08-31
Abstract: 1427412 Evaporation E H CARLSSON 31 Aug 1973 [1 Sept 1972] 41192/73 Heading BIB [Also in Divisions F3 and F4] An apparatus for contacting a first material such as a liquid, semi-solid or solid material, with a second substance, such as a drying gas, comprises a container 6 having a bed 27 of a plurality of spherical contact bodies which, in use, circulated through the container by a centrally disposed screw 16. The path of the bodies in a downward direction comprises a material application zone in which the first substance is applied to the contact bodies, a main treatment zone located in the upper part of the bed, a peripheral point of introduction of the second substance, a final treatment zone and a separating zone located beneath the bed for separating processed material from the contact bodies from Which the screw conveyor 16 takes the bodies. The screw 16 is surrounded by a rotatable sleeve 21 to form a screw conveyor and the conveyor has associated therewith a material application means and separation means, the latter comprising infeed arms 28 for feeding the contact bodies and material from the lowermost part of the abed to a gap formed by an inner separation rotor 29 and an outer stationary separation stator 31 concentric with the rotor 29. Disposed beneath the gap is a perforated separation bottom 33 through which processed material separated from the contact bodies passes. The infeed arms 28 may be of spiral configuration (Fig. 3, not shown) and the rotor 29 and stator 21 may be provided with plates 30, 32 respectively. As shown the material application means comprises a bowl 20 attached to the sleeve 21 and to which material is fed from a conduit(s) 17 by a planar receiver 19 and to which the bodies are fed by the conveyor 16, the material, in this case being a liquid. The material coated bodies are then urged from the bowl by a pair of spiral arms 25 on to spreading arms 26 from whence they drop out of the bed 27. The screw 16, receiver 19 and arms 25 are rotated by a motor 15 and the sleeve 21 by a motor through a chain 23 and sprocket 22 drive. If the material is a semi-solid or paste-like material it is fed by a screw-conveyor through the upper part of the shaft of the screw (16) and then through the wall thereof into the stream of bodies, mixing arms being provided, are fixed to the screw shaft and the other to the sleeve (21) (Fig. 4, not shown). Various materials may be fed through the upper part of the screw shaft and from there into the stream of bodies surrounding the shaft (Fig. 8, not shown). For fibrous or solid material one or more rotating carriages may be provided, each carriage having at its lower end a tapered slot co-operating with a frusto-conical spreading roller (Figs. 5 to 7, not shown). Each carriage may have two or more spreading rollers. For a chip material the chips are fed downwardly directly onto the bodies emerging from the top of the sleeve (21) whence the mixtures is fed by arms rotating with the screw and discharge passages rotating with the sleeve (Fig. 9, not shown). A passage 34 for cooling gas may be provided at the gap.