Microwave furnace

Patent metadata

Field	Value
Publication number	US-9253826-B2
Application number	US-10942108-A
Country	US
Kind code	B2
Filing date	Apr 25, 2008
Priority date	Apr 26, 2007
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

A system for melting a substance may be provided. The system may comprise a microwave generator, at least one wave guide, a melter assembly, and at least one thermal insulator. The at least one wave guide may connect the microwave generator to at least one power transfer element. The at least one wave guide may be configured to transfer microwave energy from the microwave generator to a refractory assembly. The melter assembly may comprise the refractory assembly and the at least one power transfer element connected to the refractory assembly. The refractory assembly may comprise at least one absorption element configured to transfer microwave energy, received from the at least one power transition element, into heat energy. The at least one thermal insulator may be configured to allow the microwaves to penetrate to the at least one absorption element.

First claim

What is claimed is:

1. A system for melting a substance, the system comprising:
a microwave generator;
at least one wave guide connecting the microwave generator to at least one power transfer element, the at least one wave guide configured to transfer microwave energy from the microwave generator to a refractory assembly;
a melter assembly comprising the refractory assembly and the at least one power transfer element being connected to the refractory assembly, the refractory assembly comprising;
a crucible, and
at least one absorption element adjacent the crucible, the at least one absorption element being cast of one piece and having a plurality of wedge shapes configured to convert microwave energy, received from the at least one power transfer element, into heat energy, the plurality of wedge shapes each having the same geometry and having a thin edge facing the at least one power transfer element, wherein the crucible is configured to receive the heat energy from the at least one absorption element, wherein an axis passing along the thin edge of each of the plurality of wedge shapes is substantially perpendicular to a direction from which the microwave energy is received from the at least one power transfer element; and

at least one thermal insulator configured to allow microwaves from the at least one wave guide to penetrate to the at least one absorption element wherein the at least one thermal insulator comprises at least two thermal insulation boards wherein the thermal insulator is configured to first pass the microwaves through a first of the at least two thermal insulation boards and then through a second of the at least two thermal insulation boards prior to the microwaves penetrating to the at least one absorption element.

2. The system of claim 1 , wherein the at least one thermal insulator comprises a gap between the at least two thermal insulation boards.

3. The system of claim 2 , wherein the gap comprises a sealed air gap.

4. The system of claim 2 , wherein the gap is configured to dissipate heat energy from the at least two thermal insulation boards.

5. The system of claim 1 , wherein the at least two thermal insulation boards comprise silica and alumina fiberboards.

6. The system of claim 1 , wherein the at least two thermal insulation boards are located outside a zone of highest electromagnetic energy density in the refractory assembly.

7. The system of claim 1 , wherein a first one of the at least two thermal insulation boards is adjacent the power transfer element and a second one of the at least two thermal insulation boards is adjacent the at least one absorption element.

8. The system of claim 1 , wherein the at least one absorption element comprises silicon carbide.

9. The system of claim 1 , wherein the at least one absorption element comprises a one piece cast of silicon carbide.

10. The system of claim 1 , further comprising a metal addition window configured to receive un-melted metal into the crucible.

11. The system of claim 10 , wherein the metal addition window is configured to prevent microwave energy from escaping the refractory assembly.

12. The system of claim 1 , further comprising a spout configured to allow melted metal to leave the crucible.

13. The system of claim 12 , wherein the spout is configured to prevent microwave energy from escaping the refractory assembly.

14. The system of claim 1 , wherein the refractory assembly further comprises at least one insulation element configured to retain heat in the crucible.

15. The system of claim 14 , wherein the at least one insulation element comprises fused silica.

16. The system of claim 14 , wherein the at least one insulation element comprising a plurality of individual bricks.

17. The system of claim 1 , wherein the at least one thermal insulator comprises one of the following: boards and a combination of a fibrous blanket and a board.

18. The system of claim 1 , wherein the at least one thermal insulator is configured to create a freeze plane for molten metal.

19. The system of claim 1 , wherein the thin edge is substantially parallel with the second one of the at least two thermal insulation boards.

20. The system of claim 1 , wherein the thin edge is substantially parallel with a surface of the at least one power transfer element.

21. A system for melting a substance, the system comprising:
a melter assembly comprising a refractory assembly and at least one power transfer element being connected to the refractory assembly, the refractory assembly surrounding a crucible and comprising at least one absorption element, the at least one absorption element being cast of one piece and having a plurality of wedge shapes each having the same geometry and configured to convert microwave energy into heat energy, the plurality of wedge shapes each having a thin edge facing the at least one power transfer element, wherein an axis passing along the thin edge of each of the plurality of wedge shapes is substantially perpendicular to a direction from which the microwave energy is received from the at least one power transfer element; and
at least one thermal insulator configured to allow microwaves from the at least one wave guide to penetrate to the at least one absorption element, wherein the at least one thermal insulator comprises;
at least two thermal insulation boards placed outside a zone of highest electromagnetic energy density in the refractory assembly wherein the thermal insulator is configured to first pass the microwaves through a first of the at least two thermal insulation boards and then through a second of the at least two thermal insulation boards prior to the microwaves penetrating to the at least one absorption element, and

a gap between the at least two thermal insulation boards.

22. A system for melting a substance, the system comprising:
a microwave generator;
at least one wave guide connecting the microwave generator to at least one power transfer element, the at least one wave guide configured to transfer microwave energy from the microwave generator to a refractory assembly;
a melter assembly comprising the refractory assembly and the at least one power transfer element being connected to the refractory assembly, the refractory assembly comprising at least one absorption element having a plurality of wedge shapes configured to convert microwave energy, received from the at least one power transfer element, into heat energy, the plurality of wedge shapes each having a thin edge facing the at least one power transfer element, wherein an axis passing along the thin edge of each of the plurality of wedge shapes is substantially perpendicular to a direction from which the microwave energy is received from the at least one power transfer element, the at least one absorption element comprising a one piece cast of silicon carbide;
at least one thermal insulator configured to allow microwaves from the at least one wave guide to penetrate to the at least one absorption element, wherein the at least one thermal insulator comprises:
at least two thermal insulation boards comprising silica and alumina fiberboards and being placed outside a zone of highest electromagnetic energy density in the refractory assembly, wherein a first one of the at least two thermal insulation boards is adjacent the power transfer element, a second one of the at least two thermal insulation boards is adjacent the at least one absorption element, and the first one of the at least two thermal insulati

Assignees

• Rundquist Victor F
• Gregory William J
• Gill Kevin S
• Southwire Co Llc

Inventors

• Rundquist Victor F
• Gregory William J
• Gill Kevin S

Classifications

• F27D99/0006

  Electric heating elements or system · CPC title

• H05B6/80 Primary

  Apparatus for specific applications (stoves or ranges F24C7/02) · CPC title

• F27B17/0016

  Chamber type furnaces · CPC title