GB429820A - Purifying zinc metal - Google Patents

Abstract

429,820. Distilling zinc. IMPROVED METALLURGY, Ltd., 95, Gresham Street, London.-(Assignees of Ginder, P. M., Peirce, W. M., and Waring, R. K. ; Palmerton, Pennsylvania, U.S.A.) Dec. 28, 1934, Nos. 37131 and 37132. Convention dates, Dec. 28, 1933. Addition to 395,602 and 409,531. [Class 82 (i)] Zinc is purified by the method of the parent Specification modified in that the zinc is transferred from the first to the second rectification stages as molten metal. Zinc vapour, for instance from a condenser 10, passes into a leadeliminating column 13, thence to a condenser 22 and finally to a cadmium-eliminating column 34. The columns 13, 34 are as described in the parent Specification except that the gas reservoir for the column 34 is replaced by a vent 55. The condenser 22 is connected to the column 13, Fig. 1, by a pipe 21 and to the column 34 by means of a well 25, overflow conduit 28, feed trough 29, needle valve 30 and charging-tray 33. Liquid seals are provided at 26, 32, a cleaning port at 27 and a vent at 23. In a modification, Fig. 2, the condenser is connected to the column 13 by a refractory conduit 56, heat insulated at 56<1>, a baffle 58 delivering any metal condensed in the conduit into a well 59 equipped with a skimming bar 6C and cleaning port 61. The con. denser comprises lateral passages 62, 63, cleaning ports 67 ... 70, and liquid seals 65, 66; reflux to the column 13 is provided by metal flowing from the condenser through a port 71 and needle valve 72. A modification of the column 13 is shown in Fig. 3, in which the pots 14 are contained in a flue 20 containing heating gases. Specification 392,361 is referred to.