Patent · US Expired

Thermal gravity classifying apparatus and method

US4617112A · kind A · utility

5Cited by
8References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 31, 1984
Grant dateOct 14, 1986
Priority date
Expiry dateOct 31, 2004

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02W30/52
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A thermal gravity classifier in which various nonferrous scrap metals are classified and separated, using a single tank containing two layers of molten media. Shredded nonferrous scrap containing metal constituents such as aluminum, zinc, lead, and copper or the like are introduced to the top of the tank containing an upper layer of molten zinc, floating on a lower layer of molten lead. Metals such as aluminum, having a specific gravity less than zinc, by a screw conveyor approximately parallel with the top surface. Heavier metals and alloys such as copper or the like, having a melting point above the temperature within the tank, fall through the zinc layer and are conveyed from the tank by a separate screw conveyor extending up a diagonal wall of the tank. Metals such as lead and zinc, having a melting point lower than the temperature maintained within the tank, melt and gravitate to the appropriate molten layer in the tank. The molten metals are separately withdrawn from the layers in the tank from time to time.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.