Patent GB-976623-A (GB)
Title: Improvements in and relating to the spinning of viscose
Inventor: SIDWELL GEORGE
IPC: F28F21/06
Filed: 1960-04-05
Abstract: 976,623. Heat-exchangers for viscose. COURTAULDS Ltd. April 4, 1961 [April 5, 1960], No. 11953/60. Heading B5B. [Also in Division F4] A heat-exchanger for viscose comprises an elongated body, at least a part of the surface of which is of heat-conducting, alkali-resistant material not readily corroded by weakly acid aqueous solutions, a passage within the body which is annular in cross-section and is separated from that surface only by the heat-conducting material, and an inlet and outlet communicating with opposite ends of the passage and both located adjacent the same end of the elongated body. In Fig. 1 the heat exchanger comprises a generally cylindrical container 3 of the heat conducting material, suitably F.M.B. stainless steel (B.S.S. 970) and the nickel alloys " Coronel 210 " (Registered Trade Mark) and " Hastelloy C " (Registered Trade Mark), an insert 1 of an alkali-resistant material of low heat-conductivity, suitably ebonite, polyethylene, polypropylene or polyvinyl chloride defining with the container the annular passage 7, a first part 2c in the container communicating with the passage at a point adjacent one end 9 of the insert, a second part 2e in the container adjacent the same end of the insert, and a longitudinal bore 1a within the insert, communicating with the second part and communicating with the passage at a point adjacent the other end of the insert, the bore being preferably axial to the insert, as shown. The insert may be so shaped as to retain a heat-insulating layer of air e.g. a double-walled, hollow insert may be used. In use, the container 3 is immersed in the spin bath, the viscose supply connected to the inlet part 2c and the spinning jet connected to the outlet 2e. The heat exchanger of Fig. 2 comprises four generally cylindrical members 11, 12, 13, 14 of the heat-conducting material, arranged coaxially in pairs to form two annular passages 15 and 16, an inlet port 18 adjacent one end of the first passage and an outlet port 19 adjacent the same end of the second passage, the two passages, which are preferably parallel, as shown, being in communication with each other at their other ends, via the transverse passage 17. The hollow interiors of the cylinders 12 and 14 act as channels for the spin bath liquor. The heat exchanger of Fig. 3 comprises three generally cylindrical members 21, 22, 25, disposed coaxially to form two annular passages 26, 27 at least the first and third members in sequence being of the heat-conducting material, an inlet port 28 communicating with one end of one of the passages and an outlet port 29 communicating with the adjacent end of the other passage, the passages being in communication with each other at their other ends. Preferably the intermediate cylindrical member 25 is of alkali-resistant material of low heat-conductivity. The plug 24 and ring 23 are open at their centres to allow spin bath liquor to flow into the hollow interior of the heat exchanger. If desired, port 29 may be used as the viscose inlet and port 28 as the outlet.