| 摘要 |
<p>1,134,535. Granulating. SOUTHWEST RESEARCH INSTITUTE. 7 June, 1967 [20 June, 1966], No. 26398/67. Heading B5A. Small spherical hardened particles are produced by extruding a stream of liquid material, e.g. molten wax, within a confined stream of carrier liquid, e.g. hot water which is chemically non-reactive and physically immiscible with the material, and which flows at a speed greater than the rate of extrusion of the said material causing it to break up into spherical particles which are then hardened, e.g. by cooling the carrier liquid. Apparatus providing hardened capsules in which a filler material is encased within a shell of film material comprises a conduit 10 with coaxial inner and outer tubes 11, 12 through which hot melts of filler material and film forming material respectively are fed from receptacles 15 and 14. On leaving the ends of the tubes the two extruded streams are met by a hot stream of carrier liquid supplied by conduit 20 to the conduit 10 and which, passing through a convergent part 10c, flows at a greater speed than the material streams and breaks them up into capsules which are carried through a section 10b to a vessel 24. The capsules float in the vessel and pass to a screen conveyer 26 and are received in a container 27<SP>1</SP>, carrier liquid is returned to the conduit 20 for recirculation. A heat exchanger 19 cools the carrier liquid and a heat exchanger 23 heats it. In a modified apparatus, instead of hardening the capsules by cooling, the capsules are conveyed by the liquid carrier to a vessel containing a liquid hardening medium immiscible with the carrier liquid, and the two liquids stratify in the vessel so that the capsules fall through the carrier liquid and pass to an outlet from which they are received by a conveyer. In this embodiment each capsule may comprise a filler of hexane within a shell of aqueous sodium alginate; the carrier liquid may be naphtha and the hardening medium aqueous calcium chloride.</p> |
