Abstract:
A method and recovering method of recovering zinc oxides and other metal oxides having an injection chamber where a mixture of natural gas and oxygen is formed and then ignited to form high temperature combustion gases of greater than 2000° C. with a high concentration of carbon monoxide. Then, the mixture is transported through a quiescent chamber to a feed chamber where the ignited high temperature combustion gases are mixed with finely divided material, including EAF dust. The mixture is transported to a reaction chamber, wherein zinc vapor and other metal vapors and molten slag particles are formed. The zinc vapor and other metal vapors are separated from the molten slag particles and transported to an insulated plenum. Zinc vapor and other metal vapors are mixed with air and become airborne zinc oxide and other metal oxides. The airborne zinc oxide and other metal oxides are collected.
Abstract:
A method and apparatus for recovering and refining zinc from scrap metals having a high zinc content. The scrap metals are melted in a conventional furnace and introduced in a molten state into the distillation zone of the apparatus of the invention. The apparatus comprises an atmospherically sealed vertical column having a distillation zone and a communicating superposed fractionation zone. Arranged within the vertical column is a plurality of vertically spaced horizontally staggered trays constructed of a suitable refractory material. Molten material is continuously introduced into the apparatus through a metal seal and flows downwardly in a circuitous path over the trays disposed in the distillation zone. The metal in each tray is heated to temperatures sufficient to vaporize zinc by means of precisely controllable radiant heating elements located immediately above and below each tray. The zinc vapors rise through the distilling zone in countercurrent with the descending molten metal, pass through the factionating column where various impurities are removed, and then are directed into a condenser wherein they are condensed to metallic zinc of high purity.