| 摘要 |
<PICT:0484207/III/1> <PICT:0484207/III/2> In a process for sweating mixtures of waxes, the wax mixture is chilled while in contact with a series of vertical reticulated ducts open below, through which the sweatings pass and descend to the bottom, the wax mass being also supported by vertical imperforate walls. Each reticulated duct 19, Fig. 4, is mounted within an imperforate metal tube 7 and supported therein by perforated or dished discs 20. A number of these tube assemblies are mounted in a shell 5, Fig. 1, supported in upper and lower plates 6 perforated to receive the tube members. The chamber 9 at the lower end is provided with wax inlet 11, water inlet and drain 25, wax run off pipe 26, steam coil 18, and vacuum line 30. The chamber 12 at the upper end is provided with a vent 27, a pipe 28 for admission of compressed air or inert gas and a steam pipe 29. Through the centre of each reticulated duct passes an electrically heated wire on which is threaded insulating glass beads. The space surrounding the tubes 7 in the tower 5 is connected through pipes 16 and 17 to a source of steam or cooling liquid. In operation, the lower chamber 9 is filled with water and molten wax mixture is admitted through the pipe 11 until the column is full, steam being passed into the heating coil 18. The wax is then chilled by admitting a cooling liquid to the space around the tubes 7. During chilling compressed air or inert gas is admitted through the pipe 28, whereby the wax is rendered porous and subsequent sweating is assisted. When the wax is solid, the water is run off from the chamber 9, and the core of wax in each perforated duct is melted out by passing current through the heater wire. The wax is then submitted to the sweating operation by admitting a heating fluid, e.g. steam, through the pipe 16 and current to the wires. During sweating, pipes 31 or 32 are connected to a vacuum pump, whereby reduced pressure is generated. After removal of the sweatings, the residual wax is melted out by admitting steam to the pipe 29. The heating wires may be replaced by central steam pipes. |
