DE3405613A1 - Process and device for purifying molten metallurgical silicon - Google Patents
Process and device for purifying molten metallurgical siliconInfo
- Publication number
- DE3405613A1 DE3405613A1 DE19843405613 DE3405613A DE3405613A1 DE 3405613 A1 DE3405613 A1 DE 3405613A1 DE 19843405613 DE19843405613 DE 19843405613 DE 3405613 A DE3405613 A DE 3405613A DE 3405613 A1 DE3405613 A1 DE 3405613A1
- Authority
- DE
- Germany
- Prior art keywords
- reduction furnace
- silicon
- interior
- reactive gases
- furnace
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 229910052710 silicon Inorganic materials 0.000 title claims abstract description 31
- 239000010703 silicon Substances 0.000 title claims abstract description 31
- 238000000034 method Methods 0.000 title claims abstract description 13
- 239000007789 gas Substances 0.000 claims abstract description 18
- 239000007788 liquid Substances 0.000 claims description 11
- 238000004140 cleaning Methods 0.000 claims description 9
- 238000010079 rubber tapping Methods 0.000 claims description 8
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims description 4
- 239000000460 chlorine Substances 0.000 claims description 4
- 229910052801 chlorine Inorganic materials 0.000 claims description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 3
- 239000001301 oxygen Substances 0.000 claims description 3
- 229910052760 oxygen Inorganic materials 0.000 claims description 3
- 239000010453 quartz Substances 0.000 abstract description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract description 3
- 239000003245 coal Substances 0.000 abstract description 2
- 238000000746 purification Methods 0.000 abstract description 2
- 238000010891 electric arc Methods 0.000 abstract 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 24
- 239000012535 impurity Substances 0.000 description 7
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 5
- 229910002804 graphite Inorganic materials 0.000 description 3
- 239000010439 graphite Substances 0.000 description 3
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 229910052698 phosphorus Inorganic materials 0.000 description 2
- 239000011574 phosphorus Substances 0.000 description 2
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- 239000005046 Chlorosilane Substances 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 239000002800 charge carrier Substances 0.000 description 1
- KOPOQZFJUQMUML-UHFFFAOYSA-N chlorosilane Chemical class Cl[SiH3] KOPOQZFJUQMUML-UHFFFAOYSA-N 0.000 description 1
- 101150018117 cobB gene Proteins 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 1
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 150000003376 silicon Chemical class 0.000 description 1
- 101150089009 sir2 gene Proteins 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Electric arc furnaces ; Tank furnaces
- F27B3/10—Details, accessories or equipment, e.g. dust-collectors, specially adapted for hearth-type furnaces
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/02—Silicon
- C01B33/021—Preparation
- C01B33/023—Preparation by reduction of silica or free silica-containing material
- C01B33/025—Preparation by reduction of silica or free silica-containing material with carbon or a solid carbonaceous material, i.e. carbo-thermal process
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/02—Silicon
- C01B33/037—Purification
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
- C22B9/05—Refining by treating with gases, e.g. gas flushing also refining by means of a material generating gas in situ
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Electric arc furnaces ; Tank furnaces
- F27B3/08—Hearth-type furnaces, e.g. of reverberatory type; Electric arc furnaces ; Tank furnaces heated electrically, with or without any other source of heat
- F27B3/085—Arc furnaces
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Inorganic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Silicon Compounds (AREA)
Abstract
Description
Verfahren und Vorrichtung zum Reinigen von flüssigem,Method and device for cleaning liquid,
metallurqischem Silicium Die Erfindung betrifft ein Verfahren und eine Vorrichtung zum Reinigen von flüssigem, metallurgischem und in einem Reduktionsofen geschmolzenem Silicium durch Einleiten von reaktiven Gasen in das Silicium.metallurgical silicon The invention relates to a method and a device for cleaning liquid, metallurgical and in a reduction furnace molten silicon by introducing reactive gases into the silicon.
Metallurgisches Silicium, das durch Reduktion von Quarz (sir2) mit Kohlenstoff in der Form von Kohle in einem Reduktions- oder Lichtbogenofen hergestellt ist, enthält noch Verunreinigungen, wie beispielsweise Bor und Phosphor, die eine Verwendung dieses Siliciums für elektronische Bauelemente und auch Solarzellen beeinträchtigen.Metallurgical silicon obtained by reducing quartz (sir2) with Carbon is produced in the form of coal in a reduction or arc furnace is, still contains impurities such as boron and phosphorus, the one Use of this silicon for electronic components and also affect solar cells.
Die genannten Verunreinigungen bedingen nämlich eine wesentliche Verringerung der Ladungsträger lebensdauer und/oder eine unerwünscht hohe Dotierungskonzentration an Fremdstoffen im Silicium und/oder eine zu starke Kompensation der verschiedenen Ladungsträgerarten. Wenn beispielsweise p-leitendes Silicium hergestellt werden soll und dieses zu stark mit Phosphor angereichert ist, dann kann nicht die gewünschte p-Leitfähigkeit erreicht werden.This is because the impurities mentioned require a substantial reduction the charge carrier life and / or an undesirably high doping concentration of foreign matter in the silicon and / or excessive compensation of the various Load carrier types. For example, when producing p-type silicon and this is too strongly enriched with phosphorus, then it cannot be the desired p-conductivity can be achieved.
Es ist daher erforderlich, daß das in einem Reduktionsofen gewonnene metallurgische Silicium einer Nachreinigung unterzogen wird. Hierzu wird bisher nach dem Abstich des Reduktionsofens das metallurgische Silicium in speziellen Behältern flüssig gehalten und durch Einleiten von reaktiven Gasen, wie beispielsweise chlorhaltigen Gasen oder Sauerstoff, gereinigt. Als chlorhaltige Gase können beispielsweise Chlorwasserstoff und Chlorsilane verwendet werden.It is therefore necessary that the obtained in a reduction furnace metallurgical silicon is subjected to a post-purification. This is done so far After tapping the reduction furnace, the metallurgical silicon is placed in special containers kept liquid and by introducing reactive gases such as chlorine-containing gases Gases or oxygen. As chlorine-containing gases can for example Hydrogen chloride and chlorosilanes can be used.
Bisher wird also das metallurgische Silicium in einem zusätzlichen Verfahrensschritt nach dem Abstich des Reduktionsofens in gesonderten Behältern und von seinen Verunreinigungen befreit. Dies bedeutet, daß ein hoher apparativer Aufwand für gesonderte Behälter erforderlich ist, um das Silicium zu reinigen. Auch wird zusätzliche Energie benötigt, um nach dem Abstich des Reduktionsofens das Silicium bis zum Einleiten und während des Einleitens der reaktiven Gase flüssig zu halten.So far, the metallurgical silicon is in an additional Process step after tapping the reduction furnace in separate containers and freed from its impurities. This means that a high level of apparatus Effort for separate containers is required to clean the silicon. Even additional energy is required to remove the silicon after tapping the reduction furnace to keep liquid until the introduction and during the introduction of the reactive gases.
Es ist daher Aufgabe der Erfindung, ein Verfahren der eingangs genannten Art zu schaffen, das einfach ausführbar ist und die Reinigung des Siliciums in kurzer Zeit erlaubt; auch soll eine Vorrichtung zur Durchführung dieses Verfahrens angegeben werden.It is therefore the object of the invention to provide a method of the type mentioned at the beginning Art that is easy to do and the cleaning of the silicon in a short amount of time Time allowed; a device for carrying out this method is also to be specified will.
Diese Aufgabe wird bei einem Verfahren nach dem Oberbegriff des Patentanspruches 1 erfindungsgemäß dadurch gelöst, daß die reaktiven Gase in das noch im Reduktionsofen befindliche Silicium vor dem Abstich und/oder während des Abstichs des Reduktionsofens eingeleitet werden.This task is achieved with a method according to the preamble of the patent claim 1 solved according to the invention in that the reactive gases in the still in the reduction furnace silicon present before tapping and / or during tapping of the reduction furnace be initiated.
Bei der Erfindung wird also die Reinigung des Siliciums vor dem Abstich des Reduktionsofens durchgeführt, so daß keine gesonderte Energie erforderlich ist, um das Silicium in zusätzlichen Behältern flüssig zu erhalten. Vielmehr ist bei der Erfindung vorgesehen, daß das Silicium direkt im Reduktionsofen bereits von den Verunreinigungen befreit wird.In the invention, the cleaning of the silicon before tapping of the reduction furnace, so that no separate energy is required, to keep the silicon liquid in additional containers. Rather, is at of the invention provided that the silicon is already in the reduction furnace the impurities is freed.
Eine Vorrichtung zur Durchführung des erfindungsgemäßen Verfahrens zeichnet sich dadurch aus, daß zusätzlich im Bodenbereich des Reduktionsofens Kanäle vorgesehen sind, durch die die reaktiven Gase in den Innenraum des Reduktionsofens einblasbar sind.A device for carrying out the method according to the invention is characterized by the fact that there are channels in the bottom area of the reduction furnace are provided through which the reactive gases enter the interior of the Reduction furnace can be blown.
Bei der Erfindung wird also der Reduktionsofen selbst als "Reinigungsbehälter" herangezogen, um in diesem das Silicium mittels der an sich bekannten reaktiven Gase von seinen Verunreinigungen zu befreien. Zusätzliche Behälter für die Reinigung werden also nicht benötigt.In the invention, the reduction furnace itself is used as a "cleaning container" used in this the silicon by means of the known reactive To rid gases of its impurities. Additional containers for cleaning are therefore not required.
Nachfolgend wird die Erfindung anhand der Zeichnung näher erläutert, in deren einziger Figur ein Reduktionsofen dargestellt ist.The invention is explained in more detail below with reference to the drawing, in the single figure of which a reduction furnace is shown.
Ein etwa 190 cm hoher Reduktionsofen 1 ist auf dem Boden 2 durch einzelne Träger 3 im Abstand gelagert. Der Boden des Reduktionsofens 1 selbst ist etwa 70 cm dick und hat einen Innendurchmesser von etwa 150 cm. Von diesem Boden führt ein Abstich 4 zu einer Wanne 5, in der das aus dem Abstich 4 austretende flüssige Silicium aufgefangen wird.An approximately 190 cm high reduction furnace 1 is on the floor 2 by individual Carrier 3 stored at a distance. The bottom of the reduction furnace 1 itself is about 70 cm thick and has an inner diameter of about 150 cm. From this ground we introduce Tap 4 to a tub 5, in which the emerging from the tap 4 liquid silicon is caught.
Der Innenraum 6 des Ofens 1 ist zunächst mit einer Graphitschicht 7 ausgekleidet, die noch zusätzlich mit einer etwa 6 pm dicken Pyrographitschicht 8 belegt ist.The interior 6 of the furnace 1 is initially covered with a graphite layer 7, which is additionally lined with an approximately 6 μm thick pyrographite layer 8 is occupied.
Diese Pyrographitschicht 8 gibt praktisch keine Verunreinigungen an die Schmelze im Innenraum 6 ab und verhindert außerdem, daß Verunreinigungen von außen, also beispielsweise aus der Graphitschicht 7, in den Innenraum 6 des Ofens 1 eindringen können.This pyrographite layer 8 indicates practically no impurities the melt in the interior 6 and also prevents impurities from outside, for example from the graphite layer 7, into the interior 6 of the furnace 1 can penetrate.
Im Innenraum 6 des Reduktionsofens 1 ist jeweils für eine Drehstromphase eine Elektrode angeordnet, d. h., es befinden sich drei Elektroden, von denen lediglich zwei Elektroden 9 und 10 dargestellt sind, im Innenraum 6 des Reduktionsofens 1. Diese Elektroden 9, 10 bestehen aus Graphit und haben einen Durchmesser von etwa 25 cm.In the interior 6 of the reduction furnace 1 is in each case for a three-phase phase an electrode arranged, d. That is, there are three electrodes, of which only two electrodes 9 and 10 are shown in the interior 6 of the reduction furnace 1. These electrodes 9, 10 are made of graphite and have a diameter of approximately 25 cm.
Mittels eines Hebezeuges 11 können die Elektroden 9, 10 nach oben gefahren werden, wie dies in der Fig. schematisch durch Strichpunktlinien angedeutet ist. Kühlwasserleitungen 12 dienen zur Kühlung der Elektroden 9, 10, damit diese durch die große Wärme im Innenraum 6 des Reduktionsofens 1 nicht beeinträchtigt werden.By means of a hoist 11, the electrodes 9, 10 can move upwards be driven, as indicated schematically in the figure by dash-dotted lines is. Cooling water lines 12 are used to cool the electrodes 9, 10 so that they not impaired by the great heat in the interior 6 of the reduction furnace 1 will.
Wenn in den Innenraum 6 des Reduktionsofens 1 Quarz und Kohle eingefüllt werden und der Innenraum 6 mittels der Elektroden 9, 10 aufqeheizt wird, dann bildet sich am Boden des Reduktionsofens 1 eine Schicht aus flüssigem Silicium aus, das periodisch oder kontinuierlich über den Abstich 4 aus dem Innenraum 6 zum Ausfließen gebracht wird.When filled into the interior 6 of the reduction furnace 1 quartz and carbon and the interior 6 is heated up by means of the electrodes 9, 10, then forms At the bottom of the reduction furnace 1, a layer of liquid silicon that periodically or continuously via the tap 4 from the interior 6 to flow out is brought.
Erfindungsgemäß wird dieses flüssige Silicium bereits im Innenraum 6 des Reduktionsofens 1 gereinigt. Hierzu sind im Bodenbereich des Reduktionsofens 1 Kanäle 13 vorgesehen, die zu Öffnungen 14 führen, welche im Innenraum 6 des Reduktionsofens 1 enden. Durch diese Kanäle 13 und Öffnungen 14 werden reaktive Gase, wie beispielsweise chlorhaltige Gase oder Sauerstoff, in das noch im Innenraum 6 befindliche flüssige Silicium eingeblasen. Erst nach diesem Reinigungsvorgang wird der Abstich 4 geöffnet, so daß dann gereinigtes Silicium in die Wanne 5 ausfließt. Es ist aber auch ein kontinuierlicher Betrieb möglich, bei dem das Silicium im Innenraum 6 des Reduktionsofens 1 gereinigt wird, während der Abstich 4 geöffnet ist, so daß es gleichzeitig aus dem Reduktionsofen 1 ausströmen kann.According to the invention, this liquid silicon is already in the interior 6 of the reduction furnace 1 cleaned. For this purpose are in the bottom area of the reduction furnace 1 channels 13 are provided which lead to openings 14 in the interior 6 of the reduction furnace 1 ends. Through these channels 13 and openings 14 are reactive gases, such as chlorine-containing gases or oxygen, into the liquid still in the interior 6 Blown silicon. The tap 4 is only opened after this cleaning process, so that purified silicon then flows out into the trough 5. But it is also a continuous operation possible, in which the silicon in the interior 6 of the reduction furnace 1 is cleaned while the tap 4 is open so that it is off at the same time the reduction furnace 1 can flow out.
Bei der Erfindung ist also keine gesonderte "Nachreinigungsapparatur' erforderlich. Vielmehr erfolgt das Reinigen des metallurgischen und flüssigen Siliciums bereits im Lichtbogenofen 1 durch Einleiten (vgl. den Pfeil 15) der reaktiven Gase in den Innenraum 6 über die Öffnungen 14.In the invention, there is no separate "post-cleaning apparatus" necessary. Rather, the metallurgical and liquid silicon is cleaned already in the arc furnace 1 by introducing it (see arrow 15) of the reactive gases into the interior 6 via the openings 14.
3 Patentansprüche 1 Figur3 claims 1 figure
Claims (3)
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19843405613 DE3405613A1 (en) | 1984-02-16 | 1984-02-16 | Process and device for purifying molten metallurgical silicon |
| DE20321213U DE20321213U1 (en) | 1984-02-16 | 2003-08-22 | Extending tabletop forming part of table for domestic use has drawer mechanism with rollers and telescopic sliding rails moving extension piece out from under fixed tabletop |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19843405613 DE3405613A1 (en) | 1984-02-16 | 1984-02-16 | Process and device for purifying molten metallurgical silicon |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| DE3405613A1 true DE3405613A1 (en) | 1985-08-22 |
Family
ID=6227934
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DE19843405613 Withdrawn DE3405613A1 (en) | 1984-02-16 | 1984-02-16 | Process and device for purifying molten metallurgical silicon |
Country Status (1)
| Country | Link |
|---|---|
| DE (1) | DE3405613A1 (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3635064A1 (en) * | 1986-10-15 | 1988-04-21 | Bayer Ag | METHOD FOR REFINING SILICON AND ITS PURIFIED SILICUM |
| EP0245601A3 (en) * | 1986-03-05 | 1988-08-31 | Showa Aluminum Corporation | Apparatus for treating molten metal |
| EP0304715A1 (en) * | 1987-08-19 | 1989-03-01 | Bayer Ag | Process for the continuous purification of silicon |
| EP0339644A1 (en) * | 1988-04-28 | 1989-11-02 | Messer Griesheim Gmbh | Method for refining silicon metal and ferrosilicon alloys |
| EP0720967A1 (en) * | 1995-01-09 | 1996-07-10 | Pechiney Electrometallurgie | Metallurgical silicon and ferrosilicon of low oxygen content |
| RU2131843C1 (en) * | 1998-03-30 | 1999-06-20 | Институт геохимии им.Виноградова А.П. СО РАН | Method of preparing high-purity silicon |
| WO2008119331A3 (en) * | 2007-03-30 | 2009-02-19 | Solmic Gmbh | Carbothermal reduction method and device for carrying out said method |
-
1984
- 1984-02-16 DE DE19843405613 patent/DE3405613A1/en not_active Withdrawn
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0245601A3 (en) * | 1986-03-05 | 1988-08-31 | Showa Aluminum Corporation | Apparatus for treating molten metal |
| DE3635064A1 (en) * | 1986-10-15 | 1988-04-21 | Bayer Ag | METHOD FOR REFINING SILICON AND ITS PURIFIED SILICUM |
| EP0264045A3 (en) * | 1986-10-15 | 1990-04-25 | Bayer Ag | Process for refining silicium and silicium purified in such a way |
| EP0304715A1 (en) * | 1987-08-19 | 1989-03-01 | Bayer Ag | Process for the continuous purification of silicon |
| EP0339644A1 (en) * | 1988-04-28 | 1989-11-02 | Messer Griesheim Gmbh | Method for refining silicon metal and ferrosilicon alloys |
| EP0720967A1 (en) * | 1995-01-09 | 1996-07-10 | Pechiney Electrometallurgie | Metallurgical silicon and ferrosilicon of low oxygen content |
| FR2729131A1 (en) * | 1995-01-09 | 1996-07-12 | Pechiney Electrometallurgie | SILICON AND METALLURGICAL FERROSILICIUM WITH LOW OXYGEN CONTENT |
| US5782955A (en) * | 1995-01-09 | 1998-07-21 | Pechiney Electrometallurgie | Low oxygen-content metallurgical silicon and ferrosilicon |
| RU2131843C1 (en) * | 1998-03-30 | 1999-06-20 | Институт геохимии им.Виноградова А.П. СО РАН | Method of preparing high-purity silicon |
| WO2008119331A3 (en) * | 2007-03-30 | 2009-02-19 | Solmic Gmbh | Carbothermal reduction method and device for carrying out said method |
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| 8139 | Disposal/non-payment of the annual fee |