WO2007109858A1 - Method and apparatus for heating refractory oxides - Google Patents
Method and apparatus for heating refractory oxides Download PDFInfo
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- WO2007109858A1 WO2007109858A1 PCT/AU2007/000401 AU2007000401W WO2007109858A1 WO 2007109858 A1 WO2007109858 A1 WO 2007109858A1 AU 2007000401 W AU2007000401 W AU 2007000401W WO 2007109858 A1 WO2007109858 A1 WO 2007109858A1
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- Prior art keywords
- refractory oxide
- oxide material
- melt
- crucible
- heating
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Classifications
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/02—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture in electric furnaces, e.g. by dielectric heating
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/02—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture in electric furnaces, e.g. by dielectric heating
- C03B5/021—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture in electric furnaces, e.g. by dielectric heating by induction heating
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
- C03B5/24—Automatically regulating the melting process
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/653—Processes involving a melting step
Definitions
- the present invention relates to a method and apparatus for heating refractory oxides and for materials containing refractory oxides.
- Refractory oxides are insulators at low temperatures but become conductors when their temperature is raised above a certain temperature.
- WO 2004/047495 discloses a method and apparatus for heating refractory oxides. Whilst the method and apparatus described therein can be effectively used to heat refractory oxides, it is not suited for large scale commercial processing applications where the quality of the refractory oxide varies considerably, or where the material to be heated comprises hazardous and other waste material, which while it contains refractory oxides is a material of unknown specific composition.
- the present invention seeks to ameliorate the heating of refractory oxides by at least substantially overcoming the disadvantages associated with the abovementioned processes.
- the present invention consists in a method of processing a refractory oxide material, said method comprising applying a high frequency electric field to heat said initial batch of refractory oxide material and applying a magnetic field to heat said initial batch of refractory oxide material, said high frequency electric field substantially heating said refractory oxide material to a temperature range at which said refractory oxide material undergoes a transition in electrical resistivity from an insulator to a conductor, and the magnetic field inductively heats said refractory oxide material during and/or after said transition, wherein during said heating an electrical plasma is initiated and maintained, and when said material is heated to a predetermined temperature to form a melt, characterised in that during heating the emission spectra of the plasma is measured thereby acquiring in-situ information of the chemical and physical properties of said melt.
- said in-situ information can be used to monitor and control the continuous heating of said melt.
- said in-situ information is processed, stored, analysed and reported.
- said in-situ information is used to identify batches of the material being drawn off from said melt.
- said melt is drawn off as a batch.
- said high frequency electric field and said magnetic field is imparted to said refractory oxide material via a resonant structure.
- the frequency imparted via the resonant structure is carried out within a first range of frequencies at which heating is substantially carried out by the electric field, and then subsequently lowered to a second range of frequencies at which heating is substantially carried out by the magnetic field.
- Preferably said first range of frequencies is in the range of 13MHz-42MHz.
- Preferably said second range of frequencies is in the range of 0.5MHz-13MHz.
- said refractory oxide material is held within a container and said high frequency electric field is substantially imparted to said refractory oxide material by two spaced apart plates connected to an electric circuit, and said magnetic field is imparted by an RF coil surrounding said container.
- said refractory oxide material is held with a non-faraday container and both said high frequency electric field and said magnetic field is imparted by an RP coil surrounding said non-faraday container.
- Preferably said method is used in the manufacture of a synthetic gemstone.
- Preferably said method is used to vitrify a hazardous or other waste material.
- the present invention consists in a method of processing a material of unknown specific composition that includes a refractory oxide material, said method comprising applying a high frequency electric field to heat said initial batch of material of unknown specific composition and applying a magnetic field to heat said initial batch of material of unknown specific composition, said high frequency electric field substantially heating said material of unknown specific composition to a temperature range at which refractory oxide material contained within said material of unknown specific composition undergoes a transition in electrical resistivity from an insulator to a conductor, and the magnetic field inductively heats said refractory oxide material during and/or after said transition, wherein during said heating an electrical plasma is initiated and maintained, and when said material of unknown specific composition is heated to a temperature sufficient to form a melt, characterised in that during heating the emission spectra of the plasma is measured thereby acquiring in-situ information of the chemical and physical properties of said melt.
- said in-situ information of the melt can be used to monitor and control the continuous heating of said melt.
- said in-situ information is processed, stored, analysed and reported.
- said in-situ information is used to identify at least one batch of the material being drawn off from said melt.
- said melt is drawn off as a batch.
- the present invention consists in a crucible apparatus for heating a refractory oxide material, said apparatus comprising a means for supporting said refractory oxide material, a means for imparting a high frequency electric field to said refractory oxide material and a means for imparting a magnetic field to said refractory oxide material in such a manner that when said material is heated an electrical plasma is initiated, characterised in that said apparatus further comprises acquisition means for acquiring in-situ information from the emission spectra of said plasma.
- said acquisition means is connected to at least one control means for controlling the temperature of said refractory oxide material being heated within said apparatus.
- said acquisition means is operably connected to at least one computer.
- said computer comprises a controlling means for controlling the temperature of refractory oxide material being heated within said apparatus.
- said computer is adapted to process, store, analyse and report, said in-situ information.
- said in-situ information is used to identify at least one batch of the heated material being drawn off from said melt.
- said apparatus comprises drawing off means for drawing off material heated therein.
- said drawing off means is adapted to allow material to be drawn off in batches.
- said drawing off means is adapted to allow material to be drawn off continuously, and said apparatus further comprises means for adding refractory oxide material thereto in response to material being drawn off.
- said crucible comprises a resonant structure.
- said apparatus comprising a container adapted to hold said refractory oxide material, and said means for imparting a magnetic field to said refractory oxide material is an RF coil surrounding said container.
- said crucible is connected to a variable frequency generator.
- variable frequency generator is adapted to impart a frequency in the range 0.5MHz-42MHz.
- said means for imparting a high frequency electric field includes two spaced apart plates connected to an electric circuit.
- the capacitance between said two spaced apart plates may be variably adjusted.
- At least one of said two spaced apart plates is water-cooled.
- said apparatus further comprises a sensing means for sensing the temperature of said refractory oxide material, said sensing means operably connected to a control means which varies the frequency imparted by said variable frequency generator relative to the sensed temperature.
- said means for imparting a magnetic field to said refractory oxide material is adapted to substantially heat same at a frequency in the range 0.5MHz-13 MHz.
- said means for imparting a electric field to said refractory oxide material is adapted to substantially heat same at a frequency in the range 13MHz-42 MHz.
- said crucible apparatus comprises a non-faraday container adapted to hold said refractory oxide material, and said means for imparting an electric field to said refractory oxide material is an RF coil surrounding said non-faraday container, and said means for imparting a magnetic field to said refractory oxide material is said RF coil.
- said acquisition means comprises a sensor connected to a spectrum analysis device.
- said spectrum analysis device is any one of a spectrum analyser, spectrophotometer or atomic absorption analyser.
- the present invention consists in a crucible apparatus for heating a material of unknown specific composition that includes a refractory oxide material, said apparatus comprising a means for supporting said refractory oxide material, a means for imparting a high frequency electric field to said refractory oxide material and a means for imparting a magnetic field to said refractory oxide material in such a manner that when said material is heated an electrical plasma is initiated, characterised in that said apparatus further comprises acquisition means for acquiring in-situ information from the emission spectra of said plasma.
- said acquisition means is connected to at least one computer.
- said computer comprises controlling means for controlling the temperature of material being heated within said apparatus.
- said computer is adapted to process, store, analyse and report, said in-situ information.
- said material of unknown specific composition is hazardous or other waste material.
- said material of unknown specific composition is hazardous or other waste material, and said computer is adapted to at least partially identify the composition thereof.
- said acquisition means comprises a sensor connected to a spectrum analysis device.
- said spectrum analysis device is any one of a spectrum analyser, spectrophotometer or atomic absorption analyser.
- Fig. 1 is a schematic depiction of a crucible apparatus according to a first embodiment of the present invention.
- the abovementioned document describes a crucible 1 for heating and melting refractory oxides.
- the crucible 1 is adapted to impart heating to the refractory oxide placed within container 3, firstly by imparting a high frequency electric field, typically in the range of 13 MHz -42MHz. Once the refractory oxide material reaches a temperature range where it undergoes a transition in electrical resistivity from an insulator to a conductor, the heating during and subsequent to the transition may be imparted by a magnetic field at a lower frequency, typically 0.5MHz- 13MHz. During heating an electrical plasma may be initiated and maintained within container 3.
- an embodiment of the present invention comprises a crucible 1, of the type above described in WO2004/047495.
- the crucible 1 further comprises a data acquisition device 30, in the form of a sensor 31 that is connected to a spectrum analyser 32, which is connected to a computer 40.
- the sensor 31 gathers the emission spectra of the plasma 50 during heating.
- This spectral information gathered from the plasma 50 which will further be referred to as "in-situ information” relates to the chemical and physical properties of the melt with which the plasma 50 is associated. This in-situ information may then be processed, stored and analysed.
- This in-situ information may be used in "real time” to control the melting process as the computer 50 may include a control system (not shown) connected to variable frequency generator 8 and other components of crucible 1.
- This in-situ information may be used for:
- the crucible 1 is provided with a delivery means 61 for adding material to container 3, and a draw-off means 62 for drawing off melted material from the melt created within container 3.
- the delivery means 61 and draw-off means 62 may be configured such that material being heated within crucible 1 can be processed in batches, and/or configured such that the material can be heated in a continuous process where material is added to the container 3, as material is drawn off.
- a particular advantage of the present embodiment is that it can also be used to process a material of unknown specific composition that includes at least one refractory oxide material. This is particularly useful when the process is used for heating hazardous and other waste material.
- the "in-situ information' gathered from plasma 50 via data acquisition device 30 can be used to identify the composition in the melt. This would then allow for batches of such hazardous and/or waste material, to be identified for future processing, material handling, and storage.
- the apparatus and method of the present embodiment may be used to identify waste material containing asbestos fibre/cement or radioactive material, thereby ensuring that batches of such material are handled in a safe manner and if necessary neutralised and/or vitrified. Also waste materials that are not hazardous can be identified, such that batches of such non-hazardous waste can be formed into blocks for disposal or recycling.
- the spectrum analyser 32 of the abovementioned embodiment may be any one of spectrophotometer, atomic absorption analyser or a similar device.
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- Engineering & Computer Science (AREA)
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- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Ceramic Engineering (AREA)
- Inorganic Chemistry (AREA)
- Structural Engineering (AREA)
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The present invention comprises a method of processing a refractory oxide material. The method comprises applying a high frequency electric field to heat the initial batch of refractory oxide material and applying a magnetic field to heat the initial batch of refractory oxide material. The high frequency electric field substantially heats the refractory oxide material to a temperature range at which the refractory oxide material undergoes a transition in electrical resistivity from an insulator to a conductor. The magnetic field inductively heats the refractory oxide material during and/or after the transition, wherein during the heating an electrical plasma is initiated and maintained. When the material is heated to a predetermined temperature to form a melt, during heating the emission spectra of the plasma is measured thereby acquiring in-situ information of the chemical and physical properties of the melt.
Description
METHOD AND APPARATUS FOR HEATING REFRACTORY OXIDES
TECHNICAL FIELD
The present invention relates to a method and apparatus for heating refractory oxides and for materials containing refractory oxides.
BACKGROUND
Refractory oxides are insulators at low temperatures but become conductors when their temperature is raised above a certain temperature.
It is known to heat and melt refractory oxides by various apparatus, including that described in US Patent No. 1,572,873 (Allcutt) and US Patent No. 3,205,292 (Descarin).
More recently, WO 2004/047495 (Fairfield Electronics Pty Ltd) discloses a method and apparatus for heating refractory oxides. Whilst the method and apparatus described therein can be effectively used to heat refractory oxides, it is not suited for large scale commercial processing applications where the quality of the refractory oxide varies considerably, or where the material to be heated comprises hazardous and other waste material, which while it contains refractory oxides is a material of unknown specific composition.
The present invention seeks to ameliorate the heating of refractory oxides by at least substantially overcoming the disadvantages associated with the abovementioned processes.
SUMMARY OF THE INVENTION
In a first aspect the present invention consists in a method of processing a refractory oxide material, said method comprising applying a high frequency electric field to heat said initial batch of refractory oxide material and applying a magnetic field to heat said initial batch of refractory oxide material, said high frequency electric field substantially heating said refractory oxide material to a temperature range at which said refractory oxide material undergoes a transition in electrical resistivity from an insulator to a conductor, and the magnetic field inductively heats said refractory oxide material during and/or after
said transition, wherein during said heating an electrical plasma is initiated and maintained, and when said material is heated to a predetermined temperature to form a melt, characterised in that during heating the emission spectra of the plasma is measured thereby acquiring in-situ information of the chemical and physical properties of said melt.
Preferably said in-situ information can be used to monitor and control the continuous heating of said melt.
Preferably said in-situ information is processed, stored, analysed and reported.
Preferably said in-situ information is used to identify batches of the material being drawn off from said melt.
In one preferred embodiment said melt is drawn off as a batch.
In another preferred embodiment as said heated material is drawn off from said melt additional refractory oxide material is introduced to the melt, thereby continuously processing said refractory oxide material.
Preferably said high frequency electric field and said magnetic field is imparted to said refractory oxide material via a resonant structure.
Preferably the frequency imparted via the resonant structure is carried out within a first range of frequencies at which heating is substantially carried out by the electric field, and then subsequently lowered to a second range of frequencies at which heating is substantially carried out by the magnetic field.
Preferably said first range of frequencies is in the range of 13MHz-42MHz.
Preferably said second range of frequencies is in the range of 0.5MHz-13MHz.
Preferably said refractory oxide material is held within a container and said high frequency electric field is substantially imparted to said refractory oxide material by two
spaced apart plates connected to an electric circuit, and said magnetic field is imparted by an RF coil surrounding said container.
Preferably said refractory oxide material is held with a non-faraday container and both said high frequency electric field and said magnetic field is imparted by an RP coil surrounding said non-faraday container.
Preferably said method is used in the manufacture of a synthetic gemstone.
Preferably said method is used to vitrify a hazardous or other waste material.
In a second aspect the present invention consists in a method of processing a material of unknown specific composition that includes a refractory oxide material, said method comprising applying a high frequency electric field to heat said initial batch of material of unknown specific composition and applying a magnetic field to heat said initial batch of material of unknown specific composition, said high frequency electric field substantially heating said material of unknown specific composition to a temperature range at which refractory oxide material contained within said material of unknown specific composition undergoes a transition in electrical resistivity from an insulator to a conductor, and the magnetic field inductively heats said refractory oxide material during and/or after said transition, wherein during said heating an electrical plasma is initiated and maintained, and when said material of unknown specific composition is heated to a temperature sufficient to form a melt, characterised in that during heating the emission spectra of the plasma is measured thereby acquiring in-situ information of the chemical and physical properties of said melt.
Preferably said in-situ information of the melt can be used to monitor and control the continuous heating of said melt.
Preferably said in-situ information is processed, stored, analysed and reported.
Preferably said in-situ information is used to identify at least one batch of the material being drawn off from said melt.
Preferably in one embodiment said melt is drawn off as a batch.
Preferably in another embodiment as said heated material is drawn off from said melt additional material of unknown specific composition is introduced to the melt, thereby continuously processing said material.
In a third aspect the present invention consists in a crucible apparatus for heating a refractory oxide material, said apparatus comprising a means for supporting said refractory oxide material, a means for imparting a high frequency electric field to said refractory oxide material and a means for imparting a magnetic field to said refractory oxide material in such a manner that when said material is heated an electrical plasma is initiated, characterised in that said apparatus further comprises acquisition means for acquiring in-situ information from the emission spectra of said plasma.
Preferably said acquisition means is connected to at least one control means for controlling the temperature of said refractory oxide material being heated within said apparatus.
Preferably said acquisition means is operably connected to at least one computer.
Preferably said computer comprises a controlling means for controlling the temperature of refractory oxide material being heated within said apparatus.
Preferably said computer is adapted to process, store, analyse and report, said in-situ information.
Preferably said in-situ information is used to identify at least one batch of the heated material being drawn off from said melt.
Preferably said apparatus comprises drawing off means for drawing off material heated therein.
Preferably in one embodiment, said drawing off means is adapted to allow material to be drawn off in batches.
Preferably in another embodiment, said drawing off means is adapted to allow material to be drawn off continuously, and said apparatus further comprises means for adding refractory oxide material thereto in response to material being drawn off.
Preferably said crucible comprises a resonant structure.
Preferably said apparatus comprising a container adapted to hold said refractory oxide material, and said means for imparting a magnetic field to said refractory oxide material is an RF coil surrounding said container.
Preferably said crucible is connected to a variable frequency generator.
Preferably said variable frequency generator is adapted to impart a frequency in the range 0.5MHz-42MHz.
Preferably said means for imparting a high frequency electric field includes two spaced apart plates connected to an electric circuit.
Preferably the capacitance between said two spaced apart plates may be variably adjusted.
Preferably at least one of said two spaced apart plates is water-cooled.
Preferably said apparatus further comprises a sensing means for sensing the temperature of said refractory oxide material, said sensing means operably connected to a control means which varies the frequency imparted by said variable frequency generator relative to the sensed temperature.
Preferably said means for imparting a magnetic field to said refractory oxide material is adapted to substantially heat same at a frequency in the range 0.5MHz-13 MHz.
Preferably said means for imparting a electric field to said refractory oxide material is adapted to substantially heat same at a frequency in the range 13MHz-42 MHz.
Preferably said crucible apparatus comprises a non-faraday container adapted to hold said refractory oxide material, and said means for imparting an electric field to said refractory oxide material is an RF coil surrounding said non-faraday container, and said means for imparting a magnetic field to said refractory oxide material is said RF coil.
Preferably said acquisition means comprises a sensor connected to a spectrum analysis device. Preferably said spectrum analysis device is any one of a spectrum analyser, spectrophotometer or atomic absorption analyser.
In a fourth aspect the present invention consists in a crucible apparatus for heating a material of unknown specific composition that includes a refractory oxide material, said apparatus comprising a means for supporting said refractory oxide material, a means for imparting a high frequency electric field to said refractory oxide material and a means for imparting a magnetic field to said refractory oxide material in such a manner that when said material is heated an electrical plasma is initiated, characterised in that said apparatus further comprises acquisition means for acquiring in-situ information from the emission spectra of said plasma.
Preferably said acquisition means is connected to at least one computer.
Preferably said computer comprises controlling means for controlling the temperature of material being heated within said apparatus.
Preferably said computer is adapted to process, store, analyse and report, said in-situ information.
Preferably in one embodiment, said material of unknown specific composition is hazardous or other waste material.
Preferably in another embodiment, said material of unknown specific composition is hazardous or other waste material, and said computer is adapted to at least partially identify the composition thereof.
Preferably said acquisition means comprises a sensor connected to a spectrum analysis device. Preferably said spectrum analysis device is any one of a spectrum analyser, spectrophotometer or atomic absorption analyser.
BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described with reference to drawing in which:
Fig. 1 is a schematic depiction of a crucible apparatus according to a first embodiment of the present invention.
BEST MODE OFCARRYINGOUT INVENTION The present description includes herein by reference the description and figures disclosed within International Publication No. Number WO2004/047495 entitled "Method and apparatus for heating refractory oxides" in the name of Fairfield Electronics Pty Ltd published on 3 June 2004, by the present inventor. The present specification utilises like reference numerals for like components to that disclosed in WO2004/047495.
The abovementioned document describes a crucible 1 for heating and melting refractory oxides. The crucible 1 is adapted to impart heating to the refractory oxide placed within container 3, firstly by imparting a high frequency electric field, typically in the range of 13 MHz -42MHz. Once the refractory oxide material reaches a temperature range where it undergoes a transition in electrical resistivity from an insulator to a conductor, the heating during and subsequent to the transition may be imparted by a magnetic field at a lower frequency, typically 0.5MHz- 13MHz. During heating an electrical plasma may be initiated and maintained within container 3.
As shown in Fig 1, an embodiment of the present invention comprises a crucible 1, of the type above described in WO2004/047495. The crucible 1, further comprises a data acquisition device 30, in the form of a sensor 31 that is connected to a spectrum analyser 32, which is connected to a computer 40.
The sensor 31 gathers the emission spectra of the plasma 50 during heating. This spectral information gathered from the plasma 50, which will further be referred to as "in-situ information" relates to the chemical and physical properties of the melt with which the plasma 50 is associated. This in-situ information may then be processed, stored and analysed.
This in-situ information may be used in "real time" to control the melting process as the computer 50 may include a control system (not shown) connected to variable frequency generator 8 and other components of crucible 1.
This in-situ information may be used for:
• modifying the quality or nature of the material being melted in real time;
• quality assurance purposes; • be used as record of physical and chemical properties of the particular melt;
• reference if the heating process is interrupted, and there is a need to 're-start" the heating process.
The crucible 1 is provided with a delivery means 61 for adding material to container 3, and a draw-off means 62 for drawing off melted material from the melt created within container 3. The delivery means 61 and draw-off means 62 may be configured such that material being heated within crucible 1 can be processed in batches, and/or configured such that the material can be heated in a continuous process where material is added to the container 3, as material is drawn off.
It should be understood that the present embodiment is suitable for:
• commercial applications such as the heating of refractory oxides to form synthetic gemstones, such as ruby, sapphire, cubic zirconia, etc;
• research or synthesis and characterization of novel materials; • processing hazardous waste;
• forensic analysis; and
• batch and continuous processing of ceramic and glass products.
A particular advantage of the present embodiment is that it can also be used to process a material of unknown specific composition that includes at least one refractory oxide material. This is particularly useful when the process is used for heating hazardous and other waste material. When heating a material of unknown specific composition that includes at least one refractory oxide material, the "in-situ information' gathered from plasma 50 via data acquisition device 30, can be used to identify the composition in the melt. This would then allow for batches of such hazardous and/or waste material, to be identified for future processing, material handling, and storage.
For instance the apparatus and method of the present embodiment may be used to identify waste material containing asbestos fibre/cement or radioactive material, thereby ensuring that batches of such material are handled in a safe manner and if necessary neutralised and/or vitrified. Also waste materials that are not hazardous can be identified, such that batches of such non-hazardous waste can be formed into blocks for disposal or recycling.
It should be understood that whilst the abovementioned embodiment depicts a computer 40 for processing, storing and analysing the in-situ information, it should be understood that in another not shown embodiment the data acquisition device 30 may be directly connected to the frequency control generator 8 or other control system without the use of the computer, controlling the operation of crucible 1.
It should be understood that the spectrum analyser 32 of the abovementioned embodiment, may be any one of spectrophotometer, atomic absorption analyser or a similar device.
The term "comprising" (and its grammatical variations) as used herein is used in the inclusive sense of "having" or "including" and not in the exclusive sense of "consisting only of.
Claims
1. A method of processing a refractory oxide material, said method comprising applying a high frequency electric field to heat said initial batch of refractory oxide material and applying a magnetic field to heat said initial batch of refractory oxide material, said high frequency electric field substantially heating said refractory oxide material to a temperature range at which said refractory oxide material undergoes a transition in electrical resistivity from an insulator to a conductor, and the magnetic field inductively heats said refractory oxide material during and/or after said transition, wherein during said heating an electrical plasma is initiated and maintained, and when said material is heated to a predetermined temperature to form a melt, characterised in that during heating the emission spectra of the plasma is measured thereby acquiring in-situ information of the chemical and physical properties of said melt.
2. A method of processing a refractory oxide material as claimed in claim 1, wherein said in-situ information can be used to monitor and control the continuous heating of said melt.
3. A method of processing a refractory oxide material as claimed in claim 1, wherein said in-situ information is processed, stored, analysed and reported.
4. A method of processing a refractory oxide material as claimed in claim 3, wherein said in-situ information is used to identify batches of the material being drawn off from said melt.
5. A method of processing a refractory oxide material as claimed in claim 1, wherein said melt is drawn off as a batch.
6. A method of processing a refractory oxide material as claimed in claim 1, wherein as said heated material is drawn off from said melt additional refractory oxide material is introduced to the melt, thereby continuously processing said refractory oxide material.
7. A method as claimed in claim 1, wherein said high frequency electric field and said magnetic field is imparted to said refractory oxide material via a resonant structure.
8. A method as claimed in claim 7, wherein the frequency imparted via the resonant structure is carried out within a first range of frequencies at which heating is substantially carried out by the electric field, and then subsequently lowered to a second range of frequencies at which heating is substantially carried out by the magnetic field.
9. A method as claimed in claim 8, wherein said first range of frequencies is in the range of 13MHz-42MHz.
10. A method as claimed in claim 8, wherein said second range of frequencies is in the range of 0.5MHz-BMHz.
11. A method of heating a refractory oxide material as claimed in claim 1, wherein said refractory oxide material is held within a container and said high frequency electric field is substantially imparted to said refractory oxide material by two spaced apart plates connected to an electric circuit, and said magnetic field is imparted by an RF coil surrounding said container.
12. A method of heating a refractory oxide material as claimed in claim 1, wherein said refractory oxide material is held with a non-faraday container and both said high frequency electric field and said magnetic field is imparted by an RF coil surrounding said non-faraday container.
13. A method of heating a refractory oxide material as claimed in claim 1, wherein said method is used in the manufacture of a synthetic gemstone.
14. A method of heating a refractory oxide material as claimed in claim 1, wherein said method is used to vitrify a hazardous or other waste material.
15. A method of processing a material of unknown specific composition that includes a refractory oxide material, said method comprising applying a high frequency electric field to heat said initial batch of material of unknown specific composition and applying a magnetic field to heat said initial batch of material of unknown specific composition, said high frequency electric field substantially heating said material of unknown specific composition to a temperature range at which refractory oxide material contained within said material of unknown specific composition undergoes a transition in electrical resistivity from an insulator to a conductor, and the magnetic field inductively heats said refractory oxide material during and/or after said transition, wherein during said heating an electrical plasma is initiated and maintained, and when said material of unknown specific composition is heated to a temperature sufficient to form a melt, characterised in that during heating the emission spectra of the plasma is measured thereby acquiring in-situ information of the chemical and physical properties of said melt.
16. A method of processing a material of unknown specific composition as claimed in claim 15, wherein said in-situ information of the melt can be used to monitor and control the continuous heating of said melt.
17. A method of processing a material of unknown specific composition as claimed in claim 15, wherein said in-situ information is processed, stored, analysed and reported.
18. A method of processing a material of unknown specific composition as claimed in claim 17, wherein said in-situ information is used to identify at least one batch of the material being drawn off from said melt.
19. A method of processing a material of unknown specific composition as claimed in claim 15, wherein said melt is drawn off as a batch.
20. A method of processing a refractory oxide material as claimed in claim 15, wherein as said heated material is drawn off from said melt additional material of unknown specific composition is introduced to the melt, thereby continuously processing said material.
21. A crucible apparatus for heating a refractory oxide material, said apparatus comprising a means for supporting said refractory oxide material, a means for imparting a high frequency electric field to said refractory oxide material and a means for imparting a magnetic field to said refractory oxide material in such a manner that when said material is heated an electrical plasma is initiated, characterised in that said apparatus further comprises acquisition means for acquiring in-situ information from the emission spectra of said plasma.
22. A crucible apparatus as claimed in claim 21, wherein said acquisition means is connected to at least one control means for controlling the temperature of said refractory oxide material being heated within said apparatus.
23. A crucible apparatus as claimed in claim 21, wherein said acquisition means is operably connected to at least one computer.
24. A crucible apparatus as claimed in claim 23, wherein said computer comprises a controlling means for controlling the temperature of refractory oxide material being heated within said apparatus.
25. A crucible apparatus as claimed in claim 23, wherein said computer is adapted to process, store, analyse and report, said in-situ information.
26. A crucible apparatus as claimed in claim 25, wherein said in-situ information is used to identify at least one batch of the heated material being drawn off from said melt.
27. A crucible apparatus as claimed in claim 25, wherein said apparatus comprises drawing off means for drawing off material heated therein.
28. A crucible apparatus as claimed in claim 25, wherein said drawing off means is adapted to allow material to be drawn off in batches.
29. A crucible apparatus as claimed in claim 25, wherein said drawing off means is adapted td allow material to be drawn off continuously, and said apparatus further comprises means for adding refractory oxide material thereto in response to material being drawn off.
30. A crucible apparatus as claimed in claim 21, wherein said crucible comprises a resonant structure.
31. A crucible apparatus as claimed in claim 21, comprising a container adapted to hold said refractory oxide material, and said means for imparting a magnetic field to said refractory oxide material is an RF coil surrounding said container.
32. A crucible apparatus as claimed in claim 31, wherein said crucible is connected to a variable frequency generator.
33. A crucible apparatus as claimed in claim 32, wherein said variable frequency generator is adapted to impart a frequency in the range 0.5MHz-42MHz.
34. A crucible apparatus as claimed in claim 21, wherein said means for imparting a high frequency electric field includes two spaced apart plates connected to an electric circuit.
35. A crucible apparatus as claimed in claim 34, wherein the capacitance between said two spaced apart plates may be variably adjusted.
36. A crucible apparatus as claimed in claim 34, wherein at least one of said two spaced apart plates is water-cooled.
37. A crucible apparatus as claimed in claim 32 comprising a sensing means for sensing the temperature of said refractory oxide material, said sensing means operably connected to a control means which varies the frequency imparted by said variable frequency generator relative to the sensed temperature.
38. A crucible apparatus as claimed in claim 21, wherein said means for imparting a magnetic field to said refractory oxide material is adapted to substantially heat same at a frequency in the range 0.5MHz- 13 MHz.
39. A crucible apparatus as claimed in claim 21, wherein said means for imparting a electric field to said refractory oxide material is adapted to substantially heat same at a frequency in the range 13MHz-42 MHz.
40. A crucible apparatus as claimed in claim 21, wherein said crucible comprises a non-faraday container adapted to hold said refractory oxide material, and said means for imparting an electric field to said refractory oxide material is an RF coil surrounding said non-faraday container, and said means for imparting a magnetic field to said refractory oxide material is said RF coil.
41. A crucible apparatus as claimed in claim 21 wherein said acquisition means comprises a sensor connected to a spectrum analysis device.
42. A crucible apparatus as claimed in claim 41 wherein said spectrum analysis device is any one of a spectrum analyser, spectrophotometer or atomic absorption analyser.
43. A crucible apparatus for heating a material of unknown specific composition that includes a refractory oxide material, said apparatus comprising a means for supporting said refractory oxide material, a means for imparting a high frequency electric field to said refractory oxide material and a means for imparting a magnetic field to said refractory oxide material in such a manner that when said material is heated an electrical plasma is initiated, characterised in that said apparatus further comprises acquisition means for acquiring in-situ information from the emission spectra of said plasma.
44. A crucible apparatus as claimed in claim 43, wherein said acquisition means is connected to at least one computer.
45. A crucible apparatus as claimed in claim 44, wherein said computer comprises controlling means for controlling the temperature of material being heated within said apparatus.
46. A crucible apparatus as claimed in claim 44, wherein said computer is adapted to process, store, analyse and report, said in-situ information.
47. A crucible apparatus as claimed in claim 43, wherein said material of unknown specific composition is hazardous or other waste material.
48. A crucible apparatus as claimed in claim 44, wherein said material of unknown specific composition is hazardous or other waste material, and said computer is adapted to at least partially identify the composition thereof.
49. A crucible apparatus as claimed in claim 43 wherein said acquisition means comprises a sensor connected to a spectrum analysis device.
50. A crucible apparatus as claimed in claim 49 wherein said spectrum analysis device is any one of a spectrum analyser, spectrophotometer or atomic absorption analyser.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AU2006901551 | 2006-03-27 | ||
| AU2006901551A AU2006901551A0 (en) | 2006-03-27 | Method and Apparatus for Heating Refractory Oxides |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2007109858A1 true WO2007109858A1 (en) | 2007-10-04 |
Family
ID=38540729
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/AU2007/000401 Ceased WO2007109858A1 (en) | 2006-03-27 | 2007-03-26 | Method and apparatus for heating refractory oxides |
Country Status (1)
| Country | Link |
|---|---|
| WO (1) | WO2007109858A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES2544514A1 (en) * | 2014-02-28 | 2015-08-31 | Equilab, S.A. | Equipment and procedure for preparation of x-ray or icp analysis samples (Machine-translation by Google Translate, not legally binding) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1572873A (en) * | 1923-12-29 | 1926-02-16 | Westinghouse Electric & Mfg Co | High-frequency dielectric and magnetic furnace |
| US4401625A (en) * | 1980-07-24 | 1983-08-30 | Institut De Recherches De La Siderurgie Francaise | Apparatus for preparing test samples |
| US4844612A (en) * | 1986-10-03 | 1989-07-04 | Commissariat A L'energie Atomique | Apparatus for the analysis of elements by inductive plasma spectrometry produced by air |
| US6122050A (en) * | 1998-02-26 | 2000-09-19 | Cornell Research Foundation, Inc. | Optical interface for a radially viewed inductively coupled argon plasma-Optical emission spectrometer |
| WO2004047495A1 (en) * | 2002-11-15 | 2004-06-03 | Liquid Ceramics Technology Pty Ltd | Method and apparatus for heating refractory oxides |
-
2007
- 2007-03-26 WO PCT/AU2007/000401 patent/WO2007109858A1/en not_active Ceased
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1572873A (en) * | 1923-12-29 | 1926-02-16 | Westinghouse Electric & Mfg Co | High-frequency dielectric and magnetic furnace |
| US4401625A (en) * | 1980-07-24 | 1983-08-30 | Institut De Recherches De La Siderurgie Francaise | Apparatus for preparing test samples |
| US4844612A (en) * | 1986-10-03 | 1989-07-04 | Commissariat A L'energie Atomique | Apparatus for the analysis of elements by inductive plasma spectrometry produced by air |
| US6122050A (en) * | 1998-02-26 | 2000-09-19 | Cornell Research Foundation, Inc. | Optical interface for a radially viewed inductively coupled argon plasma-Optical emission spectrometer |
| WO2004047495A1 (en) * | 2002-11-15 | 2004-06-03 | Liquid Ceramics Technology Pty Ltd | Method and apparatus for heating refractory oxides |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES2544514A1 (en) * | 2014-02-28 | 2015-08-31 | Equilab, S.A. | Equipment and procedure for preparation of x-ray or icp analysis samples (Machine-translation by Google Translate, not legally binding) |
| WO2015128522A1 (en) * | 2014-02-28 | 2015-09-03 | Equilab, S.A. | Device and method for preparing analysis samples obtained by x-ray or icp |
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