GB337149A - Improvements in or relating to apparatus for the preparation of cellulose xanthate - Google Patents

Abstract

337,149. Dassonville, M. July 1, 1929, [Convention date]. Rotary mixers.-Apparatus for the production of cellulose xanthate comprises a pair of hermetically fitting double jacketed caps of spherical calotte form with smooth internal surfaces, the caps being supported on journals and arranged so that they can be moved axially with respect to one another for discharge and cleaning purposes. The caps thus form a jacketed churn which is slowly rotated during the reaction of carbon bisulphide on the charge of alkalicellulose. The construction enables the temperature of the reacting mass to be continuously controlled and results in a more homogeneous product. Carbon bisulphide may be fed in through one of the journals and the cooling or heating fluid circulating in the jacket may also be fed through the same journal. In the drawings, the spherical caps 1 and 1<b> are assembled as shown; the connecting joint 2 made between conical members held by nuts and bolts 17<a> renders the apparatus fluid-tight. Each cap is provided with a double jacket 3, continuity being established between the jackets by means of the flexible tubes 4, even during the opening of the apparatus. The poles of the caps are provided with flanges secured to journals 7 and 8. The churn is given a slow revolving motion by means of a worm-wheel 11 and a worm 12 on the shaft of fast and loose pulleys. Removable distance pieces 17 which normally engage beneath the heads of the bolts 17<a> define and limit the linear motion of the caps for discharge and cleaning purposes. This motion is provided for by the hand-wheel 22 and gears 20 and 21 which may rotate the axially fixed nut 19 meshing with the square threaded screw 18 on the journal 8. During the rotation of the chum, the pinion 21 is disconnected. Carbon bisulphide is supplied under pressure from the gauging device 26 through a central conduit in journal 7. At the end of the reaction the carbon bisulphide vapours are sucked out of the churn through the funnel 27 connected by means of conduit 25 and a pump to a recovery apparatus. Internal ribs or baffles 29 are dipsposed in the jacket 3 to control the circulation of the heating or cooling fluid which may be made to pass from one half of the axially fixed cap to the movable cap and then back through the other half of the fixed cap. The inlet and outlet conduits leading to and from the connections 34 and 35 of the double jacket pass through the journal 7. Manholes 36 for facilitating the loading of the apparatus are provided in the caps, and the process is observed through sights 37.