Electric arc furnace dust recycling apparatus and method

Patent metadata

Field	Value
Publication number	US-9376732-B2
Application number	US-201414480189-A
Country	US
Kind code	B2
Filing date	Sep 8, 2014
Priority date	Aug 16, 2011
Publication date	Jun 28, 2016
Grant date	Jun 28, 2016

Abstract

The present technology provides an illustrative apparatus for recycling electric arc furnace (EAF) dust and method of use related to the same. The apparatus has a heat controlling region coupled to a separation volume and includes at least one magnet and a cooling region. The heating controlling region operates at a temperature sufficient to transform at least some of the EAF dust into a mixture of gaseous zinc and one or more additional metals. The magnet separates the iron-rich material from the mixture of gaseous zinc and one or more additional metals and the cooling region condenses the gaseous zinc.

First claim

What is claimed is:

1. An apparatus for recycling electric arc furnace (EAF) dust material, the apparatus comprising:
a heat controlling region configured to control a temperature of EAF dust material within the heat controlling region such that the temperature of the EAF dust material is sufficient to transform at least a portion of the EAF dust material into a mixture of gaseous zinc and one or more additional metals, wherein the one or more additional metals comprise iron-rich material and steel additives; and
a separation volume coupled to the heat controlling region and configured to receive the mixture of gaseous zinc and one or more additional metals, wherein the separation volume is configured to:
separate within the separation volume the iron-rich material from the mixture of gaseous zinc and one or more additional metals; and
direct the gaseous zinc to a cooling region; and
wherein the separation volume comprises a cooling region configured to condense the gaseous zinc within the cooling region after the iron-rich material is separated, wherein the condensing the gaseous zinc comprises condensing zinc oxide into different grades that fall out at different locations within the separation unit, and wherein the cooling region comprises a cooling air injection port configured to mix cooling air with the gaseous zinc.

2. The apparatus of claim 1 , wherein the heat controlling region comprises an inductive heater.

3. The apparatus of claim 1 , wherein the temperature sufficient to transform at least a portion of the EAF dust material into gaseous zinc and one or more additional metals is greater than about 910 degrees Celsius.

4. The apparatus of claim 1 , further comprising a first collection area for the iron-rich material, a second collection area for the stainless steel additives, and a third collection area for the condensed zinc.

5. The apparatus of claim 4 , wherein the first collection area is positioned such that it is horizontally offset from the second collection area.

6. The apparatus of claim 5 , wherein the third collection area is positioned such that it is horizontally offset from the second collection area in a direction opposite that of the first collection area.

7. The apparatus of claim 1 , further comprising a reducing agent introduction component configured to introduce a reducing agent to the EAF dust material.

8. The apparatus of claim 7 , wherein the reducing agent comprises one or more of carbon powder, carbon monoxide gas, or hydrogen gas.

9. The apparatus of claim 1 , wherein the heat controlling region is coupled to an output of an electric arc furnace and configured to receive the EAF dust material from the output of the electric arc furnace, and wherein the heat controlling region is configured to control cooling of the received EAF dust material such that the EAF dust material is transformed into the mixture of gaseous zinc and one or more additional metals.

10. The apparatus of claim 1 , wherein the separation unit comprises at least one magnet configured to magnetically separate the iron-rich material from the mixture of gaseous zinc and one or more additional metals.

11. The apparatus of claim 10 , further comprising a first collection area for the iron-rich material, a second collection area for the stainless steel additives, and a third collection area for the condensed zinc, wherein the first collection area is positioned between the second collection area and the at least one magnet such that the first collection area is horizontally offset from the second collection area.

12. The apparatus of claim 11 , wherein the heat controlling region comprises an inductively-heated vertical structure configured to heat the EAF dust material as it falls within the vertical structure, and wherein the second collection area is positioned directly below the vertical structure.

13. The apparatus of claim 10 , wherein the at least one magnet is positioned and configured to pull the iron-rich material in a direction opposite from a flow of the mixture of gaseous zinc and one or more additional metals through the separation volume.

14. The apparatus of claim 1 , wherein the separation volume comprises an outlet, and wherein the outlet comprises a filtration system configured to filter remaining undesired, un-precipitated gaseous material from the gaseous zinc and other remaining gases.

15. An apparatus for recycling electric arc furnace (EAF) dust material, the apparatus comprising:
a heat controlling region configured to control a temperature of EAF dust material within the heat controlling region such that the temperature of the EAF dust material is sufficient to transform at least a portion of the EAF dust material into a mixture of gaseous zinc and one or more additional metals, wherein the one or more additional metals comprise iron-rich material and steel additives, and wherein the heat controlling region comprises an inductively-heated vertical structure configured to heat the EAF dust material as it falls within the inductively-heated vertical structure; and
a separation volume coupled to the heat controlling region and configured to receive the mixture of gaseous zinc and one or more additional metals, wherein the separation volume is configured to:
separate within the separation volume the iron-rich material from the mixture of gaseous zinc and one or more additional metals; and
direct the gaseous zinc to a cooling region; and

wherein the separation volume comprises a cooling region configured to condense the gaseous zinc within the cooling region after the iron-rich material is separated, wherein the condensing the gaseous zinc comprises condensing zinc oxide into different grades that fall out at different locations within the separation unit.

16. The apparatus of claim 15 , wherein a collection area for stainless steel additives is positioned directly below the inductively-heated vertical structure.

17. An apparatus for recycling electric arc furnace (EAF) dust material, the apparatus comprising:
a heat controlling region configured to control a temperature of EAF dust material within the heat controlling region such that the temperature of the EAF dust material is sufficient to transform at least a portion of the EAF dust material into a mixture of gaseous zinc and one or more additional metals, wherein the one or more additional metals comprise iron-rich material and steel additives; and
a separation volume coupled to the heat controlling region and configured to receive the mixture of gaseous zinc and one or more additional metals, wherein the separation volume is configured to:
separate within the separation volume the iron-rich material from the mixture of gaseous zinc and one or more additional metals; and
direct the gaseous zinc to a cooling region; and

wherein the separation volume comprises a cooling region configured to condense the gaseous zinc within the cooling region after the iron-rich material is separated, wherein the condensing the gaseous zinc comprises condensing zinc oxide into different grades that fall out at different locations within the separation unit, and wherein the cooling region comprises a plurality of zinc oxide collection areas positioned horizontally across the cooling region, wherein each zinc oxide collection area of the plurality of zinc oxide collection areas collects a different grade of condensed zinc oxide.

Assignees

• Empire Technology Dev Llc

Inventors

• Kruglick Ezekiel

Classifications

• C22B7/02 Primary

  Working-up flue dust · CPC title

• B01D49/00

  Separating dispersed particles from gases, air or vapours by other methods · CPC title

• C22B7/001 Primary

  Dry processes · CPC title

• C21B2200/00

  Recycling of non-gaseous waste material · CPC title

• B03C3/019

  Post-treatment of gases · CPC title