High temperature metal recovery process
AssigneeMidrex Technologies, Inc.
InventorJames M. McClelland, Jr.
Life of this patent
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Abstract
An improved method and apparatus for recovering metal values from Electric Arc Furnace dust, particularly zinc and iron values, by mixing EAF dust and carbonaceous fines to form a particulate mixture; heating the mixture at a sufficient temperature and for a sufficient time to reduce and release volatile metals and alkali metals in a flue gas; collecting the released metals, and removing the metal values from the process as product.
Claims13
A method of recovering metal values from metal-containing dust, comprising the steps of:
- a. mixing metal-containing dust and carbonaceous fines to form a particulate mixture and distributing the mixture across a conveyor pan;
- b. heating the metal-containing dust and carbonaceous fines mixture in a moving bed horizontal tunnel furnace at a sufficient temperature and for a sufficient time to reduce and release volatile metals therefrom along with gaseous products;
- c. collecting the volatile metals and gases, adding dilution air, and reoxidizing the volatile metals that in this form are metal values;
- and
- d. separating the metal values generated from the gases and removing the metal values from the process as product.
Apparatus for recovering metal values from particulate metal-containing dust, comprising:
- a. a sealed horizontal furnace chamber having a horizontal conveyor situated therein;
- b. means for feeding and distributing finely divided metal-bearing particulate material onto said conveyor pan;
- c. means for direct-fired heating particulate material on said conveyor;
- d. means for monitoring the temperature of the particulate material on said conveyor pan;
- e. means for controlling by a frequency of said horizontal conveyor, therein maintaining a temperature set point;
- f. means for reducing metal values within the metal-bearing particulate material to metallized product;
- g. means for separating volatile metals from finely divided metal-bearing particulate material containing iron;
- h. means for discharging and collecting said metallized product;
- and
- i. means for adding dilution air.
Dependencies are inferred from the claim text.