| 摘要 |
<p>761,970. Distilling zinc; collecting precious metals. REVERE COPPER & BRASS, Inc. April 7. 1952 [April 12, 1951; April 14, 1951], No. 8889/52. Class 82(1) [Also in Groups XI and XII] Zinc-containing materials containing zinc oxide are mixed in granular form with granular carbonaceous material and are charged to the reaction space 31 of an electrical resistance furnace by means of a feed screw 131, the charge in the furnace forming a mass having a sloping surface 139 and the mixture being fed below this surface so as to force the materials outwardly towards the surface where it is heated by radiation to reaction temperature, preferably 2300‹F. The zinc formed is vaporized and removed to a condenser. The slag, copper matte and iron metal formed as a residue is pushed forward by movement of the charge and falls into well 37 where it is heated by radiation to a temperature at which it is sufficiently liquid to be tapped from the furnace. To ensure collection of any precious metal content of the initial material copper or copper oxide or other copper bearing material and cast iron or a reducible iron compound may be added to the charge to ensure production of sufficient iron and copper matte to remove the precious metals. Preferably carbon is used in excess to the extent of 5-30 per cent of that required to react with the reducible constituents. If the residue is not required to be sufficiently liquid to be tapped the excess of coal or coke used may be greater, say 80-125 per cent. Specification 678,263 [Group XI] is referred to.</p> |
