The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 26, 1978
Filed:
Aug. 18, 1977
Jonathan J Kim, Chelmsford, MA (US);
Thomas A Loose, Billerica, MA (US);
Chih-Chung Wang, Lexington, MA (US);
Kennecott Copper Corporation, New York, NY (US);
Abstract
Waste materials containing significant quantities of zinc oxide are mixed with carbon and a sufficient amount of copper to set the overall Zn/Cu weight ratio to a selected value below 0.66. The mixture is loaded into the top of a shaft furnace having a lower region which is heated. Hot gas rising from lower regions of the shaft furnace preheats the mixture as it descends. Rising zinc vapor is prevented from escaping the furnace because it condenses in the relatively cool preheated mixture descending down the furnace. As the mixture descends, it enters a brass production zone where zinc vapor alloys with the copper in the mixture. Further descent brings the mixture to a zinc reduction zone where the temperature is above 950.degree. C and where ZnO is reduced by carbon or carbon monoxide to produce a zinc vapor which rises coutercurrently to the charge. Molten brass and some slag is removed from a brass reservoir which forms in the bottom of the furnace.