Fusion process using an alkali metal metalate

Patent metadata

Field	Value
Publication number	US-9433038-B2
Application number	US-201514839337-A
Country	US
Kind code	B2
Filing date	Aug 28, 2015
Priority date	Dec 8, 2006
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

The product of a molten alkali metal metalate phase separation can be processed into a purified metal from a metal source. Metal sources include native ores, recycled metal, metal alloys, impure metal stock, recycle materials, etc. The method uses a molten alkali metal metalate as a process medium or solvent in purifying or extracting high value metal or metal oxides from metal sources. Vitrification methods using the silicate glass separation phase can be prepared as is or can be prepared with a particulate phase distributed throughout the silica glass phase and encapsulated and fixed within the continuous glass phase. Tungsten metal can be obtained from an alkali metal tungstate. A typically finely divided tungsten metal powder can be obtained from a variety of tungsten sources including recycled tungsten scrap, tungsten carbide scrap, low grade tungsten ore typically comprising tungsten oxide or other form of tungsten in a variety of oxidation states.

First claim

I claim:

1. A reactor structure comprising a flow-through reactor for forming a purified sodium tungstate salt phase and separating the salt phase from a glass flux phase, the reactor structure comprising:
(a) an induction coil and a reactor vessel, the reactor vessel having a stand pipe used to control flow-through reaction time by accumulating and then permitting a flow of the purified sodium tungstate, the stand pipe having a circular diameter of about 1 to about 10 centimeters;
(b) a heating component consisting of a conductive graphite reactor core positioned within the reactor vessel, the conductive graphite reactor core comprising a top portion and extending downward from the top portion, a downwardly extending cylindrical outer wall defining an interior space, the conductive graphite reactor core structure having a height of about 20 to about 200 centimeters;
(c) the reactor structure comprises a reactor-flow space positioned between the outer wall of the conductive graphite reactor core and an interior surface of the reactor vessel, the reactor-flow space having an annular thickness of about 2 to about 10 centimeters and is less than 10% of the outside diameter of the vessel; and
(d) a charge of reagents comprising a source of tungsten comprising an ore having an alkali metal metallate in particulate form at the top of the reactor vessel;

wherein the charge of reagents, the conductive graphite reactor core and the reactor vessel are inductively heated by power from the induction coil to a temperature greater than about 700° C. sufficient to produce an alkaline micro-corrosion of the source of tungsten resulting in a liquid glass flux phase separate from a phase comprising greater than 90% of a purified liquid of the sodium tungstate salt that flows through the conductive graphite reactor core and exits the vessel.

2. The reactor structure of claim 1 wherein the induction coil has a power output of about 50-2000 KW at about 1-10 KHz.

3. The reactor structure of claim 1 wherein the reactor vessel comprises a silicon carbide-carbon composite or zirconium.

4. The reactor structure of claim 1 wherein the conductive graphite reactor core comprises a graphite composite comprising greater than 30 wt.-% graphite.

5. The reactor structure of claim 1 wherein the reactor vessel is a substantially right cylindrical vessel.

6. The reactor structure of claim 1 wherein the reactor structure is sized and configured to operate at a power of 10 to 300 kilowatts at about 500 to 10,000 hertz with a flow through rate of about 10 to about 400 kilograms per hour at a reaction temperature at a point within the reactor vessel of greater than 700° C.

7. The reactor structure of claim 1 wherein the conductive graphite reactor core center of mass is positioned at approximately the center of the induction coil.

8. The reactor structure of claim 1 wherein the charge of reagents is introduced into the reactor structure in particulate form having a particle size of about 10 to 300 microns.

9. The reactor structure of claim 6 wherein the charge of reagents inside the reactor vessel is inductively heated to a temperature sufficient to form a liquid product.

10. A reactor structure comprising a flow-through reactor for forming a purified sodium tungstate salt, the reactor structure comprising:
(a) an induction coil and a substantially right cylindrical reactor vessel, the reactor vessel free of electrical heating and positioned in an interior of the induction coil, the reactor vessel having a fluid stand pipe used to control flow-through reaction time by accumulating and then permitting a flow of the purified sodium tungstate by generating a back pressure, the stand pipe having a circular diameter of about 1 to about 10 centimeters;
(b) a heating component consisting of a conductive graphite reactor core positioned within the reactor vessel, the conductive graphite reactor core comprising a top portion and extending downward from the top portion, a downwardly extending cylindrical outer wall defining an interior space, the conductive graphite reactor core structure having a height of about 20 to about 200 centimeters;
(c) the reactor structure comprises a reactor-flow space positioned between the conductive graphite reactor core and an interior surface of the reactor vessel, the reactor-flow space having an annular thickness of about 2 to about 10 centimeters and is less than 10% of the outside diameter of the vessel, the reactor structure is sized and configured to operate at a power of 10 to 300 kilowatts at about 500 to 10,000 hertz with a flow through rate of about 10 to about 400 kilograms per hour at a reaction temperature of greater than 700° C.; and
(d) a charge of reagents comprising a source of tungsten comprising an ore having a particle size of about 10 to 300 microns and an alkali metal metallate in particulate form at the top of the reactor vessel; and

wherein the charge of reagents and the reactor vessel are inductively heated by the conductive graphite reactor core with power from the induction coil to a temperature greater than about 700° C. sufficient to produce an alkaline micro-corrosion of the source of tungsten resulting in a liquid flux phase separate from a product phase comprising greater than 90% of a purified liquid of the sodium tungstate salt that flows through the conductive graphite reactor core and exits the vessel.

11. The reactor structure of claim 10 wherein the induction coil has a power output of about 50-2000 KW at about 1-10 KHz.

12. The reactor structure of claim 10 wherein the reactor vessel comprises a silicon carbide-carbon composite or zirconium.

13. The reactor structure of claim 10 wherein the conductive graphite reactor core comprises a graphite composite comprising greater than 30 wt.-% graphite.

14. The reactor structure of claim 10 wherein the conductive graphite reactor core center of mass is positioned at approximately the center of the induction coil.

15. The reactor structure of claim 10 wherein the charge of reagents is introduced into the reactor structure in particulate form having a particle size of about 10 to 300 microns.

Assignees

• Tundra Composites Llc

Inventors

• Williams Rodney K

Classifications

• F27B14/10

  Crucibles · CPC title

• F27D11/06

  Induction heating, i.e. in which the material being heated, or its container or elements embodied therein, form the secondary of a transformer · CPC title

• C03C14/004 Primary

  the non-glass component being in the form of particles or flakes · CPC title

• F27B14/061

  Induction furnaces · CPC title

• Y02W30/54

  Cross-Sectional Technologies · mapped topic