Patent GB-488708-A (GB)
Title: Improvements in and relating to methods of and apparatus for the treatment of resins
Filed: 1936-11-12
Abstract: <PICT:0488708/III/1> In a process of melting resins, e.g. copal, the resin is melted in a boiler and the molten liquid is raised from the bottom of the boiler by mechanical means, e.g. a pump, and allowed to fall through the air either back on to the surface of the liquid or into a separate vessel.  Glycerine may be admitted to the boiler to effect esterification of the molten resin.  Apparatus for carrying out the process may comprise a boiler 1 provided with a pump 2 situated at the bottom of a rising pipe 4 to the bottom of which the molten resin has access.  A baffle plate 27 is situated adjacent the upper end of the pipe 4.  A feed hopper 19 provided with a periodically-operated distributer 20 is connected to the upper end of the boiler.  A glycerine container 10 surrounded by a jacket 11 is connected to the upper part of the boiler by an upper pipe 8 and a lower pipe 9, and communicates with a condenser 17 through a pipe 18. The jacket 11 communicates with the container 10 through a connection 12.  The upper end of the container 10 is connected by a pipe 14 to an injector 15 feeding the condenser 17, the injector 15 being actuated by a pump 16 connected to the condenser.  The pipe 8 is connected by a pipe 21 to the intake of the injecter 15.  In operation, during the melting of the resin, the valves 28, 29 are closed and the valves 26, 27 are opened; the molten resin is forced up the pipe 4 by the pump 2, impinges on the baffle 27, and falls back on to the surface of the liquid in the boiler 1.  Owing to the circulation and stirring effected, the melting proceeds without frothing, and any vapours evolved are drawn through the pipe 21 by the injector 15 and passed to the condenser 17.  When esterification is to be effected, the valves 26, 27 are closed and the valves 28, 29 are opened, and glycerine is supplied from the lower part of the container 10 through the pipe 9 to the boiler.  The jacket 11 may be filled with a cooling liquid or with glycerine which is fed to the lower part of the container through the connection 12.  The vaporized products escape through the pipe 8 into the upper part of the container 10, any glycerine present being condensed and flowing through the pipe 9 into the boiler; condensation products which are lighter than the glycerine float thereon and pass through a pipe 18 to the condenser 17, and the uncondensed vapours pass through the pipe 14 to the condenser.  In a modification, a vessel situated above the bottom of the boiler surrounds the pipe 4 and receives the molten resin falling from the top of the pipe 4.  The vessel is provided at the bottom with a valve-controlled aperture, which valve is opened during esterification to allow circulation between the boiler and the vessel.  According to the Specification as open to inspection under Sect. 91, the process may be used for heating linseed oil to form stand oil.  This subject-matter does not appear in the Specification as accepted.ALSO:<PICT:0488708/IV/1> In a process of melting and esterifying resins, e.g. copal, the resin is melted in a boiler and the molten liquid is raised from the bottom of the boiler by mechanical means, e.g. a pump, and allowed to fall through the air either back on to the surface of the liquid or into a separate vessel; glycerine is then admitted to the boiler to effect esterification of the molten resin. Apparatus for carrying out the process may comprise a boiler 1 provided with a pump 2 situated at the bottom of a rising pipe 4 to the bottom of which the molten resin has access.  A baffle plate 27 is situated adjacent the upper end of the pipe 4.  A feed hopper 19 provided with a periodically-operated distributer 20 is connected to the upper end of the boiler.  A glycerine container 10 surrounded by a jacket 11 is connected to the upper part of the boiler by an upper pipe 8 and a lower pipe 9, and communicates with a condenser 17 through a pipe 18.  The jacket 11 communicates with the container 10 through a connection 12.  The upper end of the container 10 is connected by a pipe 14 to an injector 15 feeding the condenser 17, the injector 15 being actuated by a pump 16 connected to the condenser.  The pipe 8 is connected by a pipe 21 to the intake of the injector 15.  In operation, during the melting of the resin, the valves 28, 29 are closed and the valves 26, 27 are opened; the molten resin is forced up the pipe 4 by the pump 2, impinges on the baffle 27, and falls back on to the surface of the liquid in the boiler 1.  Owing to the circulation and stirring effected, the melting proceeds without frothing, and any vapours evolved are drawn through the pipe 21 by the injector 15 and passed to the condenser 17.  When esterification is to be effected, the valves 26, 27 are closed and the valves 28, 29 are opened, and glycerine is supplied from the lower part of the container 10 through the pipe 9 to the boiler.  The jacket 11 may be filled with a cooling liquid or with glycerine which is fed to the lower part of the container through the connection 12.  The vaporized products escape through the pipe 8 into the upper part of the container 10, any glycerine present being condensed and flowing through the pipe 9 into the boiler; condensation products which are lighter than the glycerine float thereon and pass through a pipe 18 to the condenser 17, and the uncondensed vapours pass through the pipe 14 to the condenser.  In a modification, a vessel situated above the bottom of the boiler surrounds the pipe 4 and receives the molten resin falling from the top of the pipe 4.  The vessel is provided at the bottom with a valve-controlled aperture, which valve is opened during esterification to allow circulation between the boiler and the vessel.