EP0378842A1 - Protector sleeve for current supply elements - Google Patents

Protector sleeve for current supply elements Download PDF

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Publication number
EP0378842A1
EP0378842A1 EP89123755A EP89123755A EP0378842A1 EP 0378842 A1 EP0378842 A1 EP 0378842A1 EP 89123755 A EP89123755 A EP 89123755A EP 89123755 A EP89123755 A EP 89123755A EP 0378842 A1 EP0378842 A1 EP 0378842A1
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EP
European Patent Office
Prior art keywords
mass
anode
binder
protective jacket
jacket according
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EP89123755A
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German (de)
French (fr)
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EP0378842B1 (en
Inventor
Michael Müllerthann
Werner Dr. Weuster
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HOOGOVENS ALUMINIUM HUETTENWERK
Voerde Aluminium GmbH
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HOOGOVENS ALUMINIUM HUETTENWERK
Hoogovens Aluminium Huttenwerk GmbH
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    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
    • C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
    • C25C3/08—Cell construction, e.g. bottoms, walls, cathodes
    • C25C3/12—Anodes
    • C25C3/125—Anodes based on carbon

Definitions

  • the invention relates to a protective jacket for protecting anode power supply elements of electrolytic cells for aluminum production of the type mentioned in the preamble of claim 1.
  • Such protective jackets are already known (CH-PS 625 560, DE-AS 2 547 061). They are used to protect the current supply elements to the actual anodes, which mainly consist of electrode carbon (anode carbon) or block anodes, against the electrolyte bath. Since the power supply elements are often made of steel, when the power supply elements are immersed in the electrolyte bath, the steel dissolves, which on the one hand reduces the degree of purity of the aluminum during aluminum production and on the other hand reduces the service life of the anodes in the electrolysis cell, in which aluminum is produced by electrolysis of aluminum oxide is produced in a cryolite melt.
  • the protective sheath of the known type has, as a binder for the petroleum coke, the mass of coal tar pitch surrounding the transition point of the power supply element to the anode, the softening point of which is approximately 113 ° C. and a coking value (according to Conradson) of approximately 56% and a density of over 1.3 g / ml.
  • protective sheaths of this type release benzo (a) pyrene, in particular when the power supply pins are attached to the anode coals, as a result of which the health and, in particular, the persons handling the anodes can be adversely affected.
  • the invention has for its object to improve the protective jacket of the type mentioned with simple means to the extent that it causes less health risks despite simple and inexpensive to manufacture and therefore makes the establishment of special cleaning systems unnecessary. Nevertheless, the protective jacket is intended to ensure a long anode service life in the electrolytic cell.
  • the invention consists in that the binding agent of the mass comprising the petroleum coke consists of petroleum pitch all around the connection point between the power supply element and the anode.
  • Such petroleum pitch with the following values is preferred: Softening point (after Mettler) 100-150 ° C (after Kraemer-Sarnow) 70-130 ° C Coking value (after Conradson) 40 - 45% Ash content up to 0.10% Sulfur content up to 0.30% especially up to 0.25% Density (at 20 ° C) 1.15 - 1.25 g / cm3 especially 1.2 g / cm3 Brightness (according to Barrett) 16 colour dark brown to black
  • Such brown-black petroleum pitch sells e.g. the company Rütgerswerke AG, Duisburg, under the trade name WR-Harz 95 D; it forms a mixture of different thermopolymers and is unsaponifiable and soluble in aromatics and chlorinated hydrocarbons.
  • WR-Harz 95 D Such brown-black petroleum pitch
  • it also contains polystyrenes, polycyclopentadienes and polyolefins.
  • the object set in the invention can be achieved particularly well if the proportion of binder in the composition is between 32 and 45%.
  • the petroleum coke should consist of 40-70% fine grain with a grain size of up to about 0.3 mm, while the rest of the petroleum coke essentially consists of coarse grain with a grain size between about 0.5 and 5 mm.
  • the protective sheath according to the invention not only with respect to the previously known protective sheath containing coal tar pitch as a binder production, but above all it has far less harmful effects on the environment:
  • the benzo (a) pyrene level is not only significantly undercut at a release threshold of 2000 ng / m3, but also an expected TRK value of 2000 ng / m3 permanently observed safely.
  • the new protective jacket also forms an improved adhesion both to the anode surface and to the surface of the power supply elements, in particular steel. Petroleum pitch is even more advantageous than bitumen as a binder.
  • transition or connection area between the pin 3 and the anode 1 is surrounded in a ring with a mass 6, which consists of petroleum coke and a binder.
  • the protective jacket is completed by an aluminum ring 5 around the mass 6.
  • the outer sides of the aluminum ring 5 of the anode carbon or block anode 1 are sprayed with an aluminum layer.
  • the mass 6 consists on the one hand of coarse grain 6a and on the other hand of fine grain 6b of a petroleum coke, which is used with the help of petroleum pitch as a binder 6c is held together.
  • the coarse grain 6a has an average grain size of between 1 and 3 mm, while the fine grain falls through a sieve which retains grains of 0.3 mm and larger.
  • the proportion of fine grain 6b is 40-70% of petroleum coke, while the rest of it consists of coarse grain 6a, so that the total proportion of fine grain 6b and coarse grain 6a, ie petroleum coke, in mass 6 is between 55 and 75% and the proportion Petroleum pitch as a binder 6c is between 25 and 45%, in particular between 30 and 42%. In about 32%, the best results can be achieved not only with regard to reducing the health hazard, but also with regard to the mechanical. Strength.
  • the starting material is mixed at 130-200 ° C for 20 to 25 minutes and molded in blocks or granulated in a cooling drum.
  • the molded blocks are stored and, depending on requirements, crushed and bagged to approx. 3 - 12 mm in a crusher or stored in a silo. If necessary, the petroleum coke can only be mixed with the binder on site and used to manufacture the protective jacket.
  • the aluminum ring 5 is placed around the transition point in question on the surface 1b of the anode 1 in narrow annular grooves and then the mass 6 is filled into the inner region between the aluminum ring 5 and the pin 3 of the power supply element.
  • the top of the mass 6 is sealed so that when the anode 1, including the rings 5, which are made in particular of aluminum, are sprayed with liquid aluminum, no mass 6 is whirled up by the spray jet. Sealing also prevents alumina from entering the electrolytic cell. Sealing takes place in particular by sintering the mass at approximately 600 ° C., as a result of which the surface is covered with a dense sinter skin 6d, which has proven to be particularly advantageous.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrolytic Production Of Metals (AREA)
  • Emergency Protection Circuit Devices (AREA)

Abstract

To reduce health hazards by means of protective sleeves (5) used to protect anode current supply elements in electrolytic cells, petroleum pitch is used in a proportion of between, in particular, 32 and 42%, as a binder for the material (6) which consists, in particular, of petroleum coke. <IMAGE>

Description

Die Erfindung bezieht sich auf einen Schutzmantel zum Schutz von Anoden-Stromzuführungselementen von Elektrolysezellen für die Aluminiumherstellung der im Oberbegriff des Anspruches 1 genannten Gattung.The invention relates to a protective jacket for protecting anode power supply elements of electrolytic cells for aluminum production of the type mentioned in the preamble of claim 1.

Derartige Schutzmäntel sind bereits bekannt (CH-PS 625 560, DE-AS 2 547 061). Sie dienen dazu, die Stromzuführungs­elmente zu den eigentlichen Anoden, die vorwiegend aus Elektrodenkohle (Anodenkohle) bzw. Blockanoden bestehen, gegenüber dem Elektrolytbad zu schützen. Da die Stromzu­führungselemente vielfach aus Stahl bestehen, ergibt sich beim Eintauchen solcher Stromzuführungselemente in das Elektrolytbad eine Auflösung des Stahls, wodurch einerseits der Reinheitsgrad des Aluminiums bei der Aluminiumherstellung vermindert, andererseits aber die Standzeit der Anoden in der Elektrolysezelle vermindert wird, in der Aluminium durch Elektrolyse von Aluminiumoxyd in einer Kryolithschmelze erzeugt wird. Der Schutzmantel der bekannten Gattung weist als Bindemittel für den Petrolkoks der die Übergangsstelle des Stromzuführungselements zur Anode umgebenden Masse Stein­kohlenteerpech auf, dessen Erweichungspunkt bei etwa 113 °C liegt und der einen Verkokungswert (n. Conradson) von ca. 56 % sowie eine Dichte von über 1,3 g/ml aufweist. Es hat sich jedoch gezeigt, daß derartige Schutzmäntel insbe­sondere beim Anbringen der Stromzuführungszapfen an den Anodenkohlen Benzo(a)pyren freigeben, wodurch die Umwelt und vor allem die mit den Anoden umgehenden Personen gesund­heitlich beeinträchtigt werden können.Such protective jackets are already known (CH-PS 625 560, DE-AS 2 547 061). They are used to protect the current supply elements to the actual anodes, which mainly consist of electrode carbon (anode carbon) or block anodes, against the electrolyte bath. Since the power supply elements are often made of steel, when the power supply elements are immersed in the electrolyte bath, the steel dissolves, which on the one hand reduces the degree of purity of the aluminum during aluminum production and on the other hand reduces the service life of the anodes in the electrolysis cell, in which aluminum is produced by electrolysis of aluminum oxide is produced in a cryolite melt. The protective sheath of the known type has, as a binder for the petroleum coke, the mass of coal tar pitch surrounding the transition point of the power supply element to the anode, the softening point of which is approximately 113 ° C. and a coking value (according to Conradson) of approximately 56% and a density of over 1.3 g / ml. However, it has been shown that protective sheaths of this type release benzo (a) pyrene, in particular when the power supply pins are attached to the anode coals, as a result of which the health and, in particular, the persons handling the anodes can be adversely affected.

Eine Abhilfe solcher umweltbelastenden Anlage wäre die In­stallierung von Filter- und dergleichen Entsorgungsanlagen, wozu jedoch große Investitionskosten aufzubringen sind, zumal solche Filter in der Regel auch explosionsgeschützt ausgebil­det sein müssen. Trotz dieser hohen Aufwendungen müssen aber auch die Filter- oder dergleichen Anlagen wieder entsorgt werden, was zu neuen Problemen führt.A remedy for such an environmentally damaging system would be the installation of filter and similar disposal systems, which, however, entails high investment costs, especially since such filters generally also have to be explosion-proof. Despite these high expenses, the filter or similar systems must also be disposed of again, which leads to new problems.

Der Erfindung liegt die Aufgabe zugrunde, den Schutzmantel der eingangs genannten Gattung mit einfachen Mitteln dahin­gehend zu verbessern, daß er trotz einfacher und preis­günstiger Herstellbarkeit weniger Gesundheitsgefährdungen verursacht und daher die Einrichtung von Reinigungs-Spezial­anlagen überflüssig macht. Dennoch soll der Schutzmantel eine lange Anodenstandzeit in der Elektrolysezelle gewähr­leisten.The invention has for its object to improve the protective jacket of the type mentioned with simple means to the extent that it causes less health risks despite simple and inexpensive to manufacture and therefore makes the establishment of special cleaning systems unnecessary. Nevertheless, the protective jacket is intended to ensure a long anode service life in the electrolytic cell.

Die Erfindung besteht darin, daß das Bindemittel der den Petrolkoks aufweisenden Masse rings um die Verbindungsstelle zwischen dem Stromzuführungselement und der Anode aus Petrolpech besteht. Bevorzugt wird ein solches Petrolpech mit folgenden Werten: Erweichungspunkt (nach Mettler) 100 - 150 °C (nach Kraemer-Sarnow) 70 - 130 °C Verkokungswert (nach Conradson) 40 - 45 % Ascheanteil bis 0,10 % Schwefelanteil bis 0,30 % insb.bis 0,25 % Dichte (bei 20 °C) 1,15 - 1,25 g/cm³ insb. 1,2 g/cm³ Helligkeit (nach Barrett) 16 Farbe dunkelbraun bis schwarz The invention consists in that the binding agent of the mass comprising the petroleum coke consists of petroleum pitch all around the connection point between the power supply element and the anode. Such petroleum pitch with the following values is preferred: Softening point (after Mettler) 100-150 ° C (after Kraemer-Sarnow) 70-130 ° C Coking value (after Conradson) 40 - 45% Ash content up to 0.10% Sulfur content up to 0.30% especially up to 0.25% Density (at 20 ° C) 1.15 - 1.25 g / cm³ especially 1.2 g / cm³ Brightness (according to Barrett) 16 colour dark brown to black

Ein derartiges braun-schwarzes Petrolpech vertreibt z.B. die Firma Rütgerswerke AG, Duisburg, unter dem Handelsnamen WR-­Harz 95 D; es bildet ein Gemisch verschiedener Thermo­polymerisate und ist unverseifbar sowie in Aromaten und Chlorkohlen-Wasserstoffen löslich. Es enthält neben Poly-­Cumaron-Inden auch Polystyrole, Polycyclopentadiene und Polyolefine.Such brown-black petroleum pitch sells e.g. the company Rütgerswerke AG, Duisburg, under the trade name WR-Harz 95 D; it forms a mixture of different thermopolymers and is unsaponifiable and soluble in aromatics and chlorinated hydrocarbons. In addition to poly-coumarone indene, it also contains polystyrenes, polycyclopentadienes and polyolefins.

Es ist an sich bekannt (US-PS 4 086 156, DE-OS 2 308 971, 2 243 490), Petrolpech insbesondere im Gemisch mit Steinkoh­lenteerpech als Bindemittel zu verwenden; dabei werden jedoch die Elektroden selbst hergestellt und nicht deren Schutzman­tel, dabei wird aber wegen Rissebildung von deren Verwendung abgeraten, sofern nicht Spezialmaßnahmen ergriffen werden.It is known per se (US Pat. No. 4,086,156, DE-OS 2,308,971, 2,243,490) to use petroleum pitch as a binder, particularly in a mixture with coal tar pitch; however, the electrodes themselves are manufactured and not their protective sheath, but their use is not recommended due to the formation of cracks, unless special measures are taken.

Es hat sich aber gezeigt, daß bei Verwendung des oben ge­nannten Bindemittels die gestellte Aufgabe bei der Erfin­dung insbesondere dann besonders gut gelöst werden kann, wenn der Bindemittelanteil an der Masse zwischen 32 und 45 % beträgt. Dabei sollte das Petrolkoks zu 40 - 70 % aus Feinkorn einer Korngröße von bis zu etwa 0,3 mm bestehen, während der Rest des Petrolkokses im wesentlichen aus Grobkorn einer Korngröße zwischen etwa 0,5 und 5 mm besteht.It has been shown, however, that when using the above-mentioned binder, the object set in the invention can be achieved particularly well if the proportion of binder in the composition is between 32 and 45%. The petroleum coke should consist of 40-70% fine grain with a grain size of up to about 0.3 mm, while the rest of the petroleum coke essentially consists of coarse grain with a grain size between about 0.5 and 5 mm.

Es hat sich gezeigt, daß der erfindungsgemäße Schutzmantel den bisher bekannten, Steinkohlenteerpech als Bindemittel aufweisenden Schutzmantel nicht nur hinsichtlich der ein­ fachen Herstellung entspricht, sondern vor allem weitaus weniger umweltbelastende Wirkungen ausübt: So wird die Benzo(a)pyren-Belastung nicht nur bei einer Auslöseschwelle von 2000 ng/m³ erheblich unterschritten, sondern wird auch ein zu erwartender TRK-Wert von 2000 ng/m³ dauerhaft sicher eingehalten. Infolgedessen müssen keine zusätzlichen Reini­gungsanlagen installiert werden und erübrigt sich auch die Entsorgung derselben. Überraschenderweise bildet der neue Schutzmantel auch eine verbesserte Haftung sowohl an der Anodenoberfläche als auch an der Oberfläche der Stromzu­führungselemente, insbesondere Stahl. Sogar gegenüber Bitumen ist das Petrolpech als Bindemittel wesentlich vorteilhafter.It has been shown that the protective sheath according to the invention not only with respect to the previously known protective sheath containing coal tar pitch as a binder production, but above all it has far less harmful effects on the environment: For example, the benzo (a) pyrene level is not only significantly undercut at a release threshold of 2000 ng / m³, but also an expected TRK value of 2000 ng / m³ permanently observed safely. As a result, no additional cleaning systems need to be installed and there is no need to dispose of them. Surprisingly, the new protective jacket also forms an improved adhesion both to the anode surface and to the surface of the power supply elements, in particular steel. Petroleum pitch is even more advantageous than bitumen as a binder.

Es ist besonders vorteilhaft, ein Petrolpech mit einem Erwei­chungspunkt zwischen 110 °C und 120 °C mit einer Dichte zwi­schen 1,10 und 1,25 g/cm³ und mit einem Verkokungswert zwischen 35 % und 50 % als Bindemittel zu verwenden.It is particularly advantageous to use petroleum pitch with a softening point between 110 ° C and 120 ° C with a density between 1.10 and 1.25 g / cm³ and with a coking value between 35% and 50% as a binder.

Ein Ausführungsbeispiel der Erfindung wird anhand der Zeichnung im folgenden noch näher erläutert: Dabei zeigen:

  • Fig. 1 eine Seitenansicht, teilweise im Querschnitt, einer mit einem Stromzuführungselement versehene Anode, wie sie bei der Aluminiumherstellung in Elektrolyse­zellen verwendet wird;
  • Fig. 2 den gleichen Gegenstand wie von Fig. 1 in einer spä­teren Verfahrensstufe, wenn ein großer Teil der Kohlenstoffanode im Elektrolytbad bereits ver­braucht ist und die Oberflächen der Anode von einem Teil des Elektrolytbades überdeckt sind, und
  • Fig. 3 einen Teilausschnitt aus Fig. 1/2 im Bereich der Übergangsstelle zwischen dem Stromzuführungselement und der Anode.
An embodiment of the invention is explained in more detail below with reference to the drawing:
  • 1 is a side view, partly in cross section, of an anode provided with a current supply element, as is used in the production of aluminum in electrolytic cells;
  • FIG. 2 shows the same object as in FIG. 1 in a later process stage when a large part of the carbon anode in the electrolyte bath has already been used up and the surfaces of the anode are covered by part of the electrolyte bath, and
  • Fig. 3 is a partial section of Fig. 1/2 in the area of the transition point between the power supply element and the anode.

Gemäß Fig. 1 ist eine sogenannte "Blockanode", bestehend aus mit insbesondere Steinkohlenteerpech gebundenem Elektroden­koks, als Anode 1 mit einem Stromzuführungselement derart verbunden, daß die von dem Joch 2 des aus Stahl bestehenden Stromzuführungselements abstehenden Zapfen 3 in Aussparungen an der Oberseite der Anode 1 versenkt und mit Hilfe von Stampfmasse oder Grauguß GG verankert sind.1, a so-called "block anode", consisting of electrode coke bonded with coal tar pitch in particular, is connected as anode 1 to a power supply element in such a way that the pins 3 protruding from the yoke 2 of the steel power supply element into recesses on the top of the anode 1 are sunk and anchored with the aid of rammed earth or cast iron GG.

Darüber hinaus ist der Übergangs- bzw. Verbindungsbereich zwischen dem Zapfen 3 und der Anode l ringförmig mit einer Masse 6 umgeben, die aus Petrolkoks und einem Bindemittel besteht. Der Schutzmantel wird vervollständigt durch einen Aluminiumring 5 rings um die Masse 6. Zusätzlich sind die Außenseiten des Aluminiumrings 5 der Anodenkohle bzw. Blockanode 1 mit einer Aluminiumschicht besprüht.In addition, the transition or connection area between the pin 3 and the anode 1 is surrounded in a ring with a mass 6, which consists of petroleum coke and a binder. The protective jacket is completed by an aluminum ring 5 around the mass 6. In addition, the outer sides of the aluminum ring 5 of the anode carbon or block anode 1 are sprayed with an aluminum layer.

Während zu Beginn des Elektrolyseverfahrens nur der untere Teil der Anode 1 in das Elektrolytbad eintaucht, wird mit zu­nehmendem Abbrennen der Blockanode 1 diese immer tiefer in das Elektrolytbad eingesenkt, bis gemäß Fig. 2 auch die Ober­seite 1b der Anode 1 von Elektrolytbad 8 überflutet wird. Dadurch, daß das Elektrolytbad 8 infolge der Anbringung des aus der Masse 6 und dem Aluminiumring 5 gebildeten Schutz­mantels der Zutritt zu den Stahlteilen des Stromzuführungs­elements verwehrt wird, kann sich der Stahl nicht zersetzen bzw. auflösen, was zum vorzeitigen Ausfall der Restanode 1a führen würde. Die Anbringung des Schutzmantels erlaubt daher eine Verlängerung der Anodenstandzeit in der Elektro­lysezelle und verbilligt daher die Aluminiumherstellung.While at the beginning of the electrolysis process only the lower part of the anode 1 is immersed in the electrolyte bath, as the block anode 1 burns, it is immersed ever deeper into the electrolyte bath until the top side 1b of the anode 1 is also flooded with the electrolyte bath 8. Because the electrolyte bath 8 is prevented from accessing the steel parts of the power supply element due to the application of the protective jacket formed from the mass 6 and the aluminum ring 5, the steel cannot decompose or dissolve, which would lead to the premature failure of the residual anode 1a. The application of the protective jacket therefore allows the anode service life in the electrolysis cell to be extended and therefore reduces the cost of aluminum production.

Gemäß Fig. 3 ist gezeigt, daß die Masse 6 einerseits aus Grobkorn 6a und andererseits aus Feinkorn 6b eines Petrol­kokses besteht, das mit Hilfe von Petrolpech als Bindemittel 6c zusammengehalten wird. Das Grobkorn 6a weist eine durch­schnittliche Korngröße zwischen 1 und 3 mm auf, während das Feinkorn durch ein Sieb hindurchfällt, das Körner mit 0,3 mm und größer zurückhält. Der Anteil des Feinkorns 6b beträgt 40 - 70 % des Petrolkokses, während der Rest desselben aus Grobkorn 6a besteht, so daß der Gesamtanteil an Feinkorn 6b und Grobkorn 6a, d.h. an Petrolkoks, an der Masse 6 zwischen 55 und 75 % und der Anteil an Petrolpech als Bindemittel 6c zwischen 25 und 45 %, inbesondere zwischen 30 und 42 % beträgt. Bei etwa 32 % sind die besten Ergebnisse erzielbar nicht nur hinsichtlich der Verminderung der Gesundheitsgefährdung, sondern auch hinsichtlich der mechan. Festigkeit.According to FIG. 3 it is shown that the mass 6 consists on the one hand of coarse grain 6a and on the other hand of fine grain 6b of a petroleum coke, which is used with the help of petroleum pitch as a binder 6c is held together. The coarse grain 6a has an average grain size of between 1 and 3 mm, while the fine grain falls through a sieve which retains grains of 0.3 mm and larger. The proportion of fine grain 6b is 40-70% of petroleum coke, while the rest of it consists of coarse grain 6a, so that the total proportion of fine grain 6b and coarse grain 6a, ie petroleum coke, in mass 6 is between 55 and 75% and the proportion Petroleum pitch as a binder 6c is between 25 and 45%, in particular between 30 and 42%. In about 32%, the best results can be achieved not only with regard to reducing the health hazard, but also with regard to the mechanical. Strength.

Das Ausgangsmaterial wird bei 130-200 °C 20 bis 25 Minuten lang gemischt und in Blöcken abgeformt oder in einer Kühl­trommel granuliert. Die abgeformten Blöcke werden gelagert und je nach Bedarf in einer Brechanlage auf ca. 3 - 12 mm zerkleinert und abgesackt oder in einem Silo gelagert. Im Bedarfsfall kann das Petrolkoks mit dem Bindemittel aber auch erst an Ort und Stelle vermischt und zur Herstellung des Schutzmantels verwendet werden. Dabei wird zuerst der Aluminiumring 5 rings um die betreffende Übergangsstelle an der Oberfläche 1b der Anode 1 in schmalen ringförmigen Nuten angebracht und danach die Masse 6 in den Innenbereich zwischen dem Aluminiumring 5 und dem Zapfen 3 des Stromzu­führungselements eingefüllt wird. Nach dem Einfüllen wird die Oberseite der Masse 6 abgedichtet, damit beim Besprühen der Anode 1 einschließlich der insbesondere aus Aluminium be­stehenden Ringe 5 mit flüssigem Aluminium keine Masse 6 durch den Sprühstrahl aufgewirbelt wird. Das Abdichten verhindert auch das Eindringen von Aluminiumoxyd aus der Elektrolyse­zelle. Das Abdichten erfolgt insbesondere durch Sintern der Masse bei ca. 600 °C, wodurch die Oberfläche mit einer dichten Sinterhaut 6d überzogen wird, was sich als besonders vorteilhaft erwiesen hat.The starting material is mixed at 130-200 ° C for 20 to 25 minutes and molded in blocks or granulated in a cooling drum. The molded blocks are stored and, depending on requirements, crushed and bagged to approx. 3 - 12 mm in a crusher or stored in a silo. If necessary, the petroleum coke can only be mixed with the binder on site and used to manufacture the protective jacket. First, the aluminum ring 5 is placed around the transition point in question on the surface 1b of the anode 1 in narrow annular grooves and then the mass 6 is filled into the inner region between the aluminum ring 5 and the pin 3 of the power supply element. After filling, the top of the mass 6 is sealed so that when the anode 1, including the rings 5, which are made in particular of aluminum, are sprayed with liquid aluminum, no mass 6 is whirled up by the spray jet. Sealing also prevents alumina from entering the electrolytic cell. Sealing takes place in particular by sintering the mass at approximately 600 ° C., as a result of which the surface is covered with a dense sinter skin 6d, which has proven to be particularly advantageous.

Claims (7)

1. Schutzmantel zum Schutz von Anoden-Stromzuführungsele­menten von Elektrolysezellen für die Aluminiumherstel­lung bei der das oder die mit der Anode, inbesondere einer Kohlenstoffanode, verbundene(n) Stromzuführungselement(e), zum Beispiel Stromzuführungszapfen oder -spaten, im Bereich rings um die Übergangs- bzw. Verbindungsstelle(n) zur Anode mit (je) einer Masse aus Petrolkoks und einem Bindemittel umgeben ist (sind), dadurch gekennzeichnet, daß das Bindemittel (6c) der Masse (6) aus Petrolpech be­steht.1. Protective sheath for protecting anode power supply elements of electrolysis cells for aluminum production in which the power supply element (s) connected to the anode, in particular a carbon anode, for example power supply pins or spades, in the area around the transition or connection point (s) to the anode is (are) surrounded by a mass of petroleum coke and a binder, characterized in that the binder (6c) of the mass (6) consists of petroleum pitch. 2. Schutzmantel nach Anspruch 1, dadurch gekennzeichnet, daß der Anteil des Petrolkokses an der aus diesem und dem Bindemittel (6c) gebildeten Masse (6) 55 - 75 % beträgt.2. Protective jacket according to claim 1, characterized in that the proportion of petroleum coke in the mass (6c) formed from this and the binder (6) is 55-75%. 3. Schutzmantel nach Anspruch 1 oder 2, dadurch gekennzeich­net,
daß der Anteil des Bindemittels an der Masse zwischen 32 % und 42 % beträgt.3. Protective jacket according to claim 1 or 2, characterized in
that the proportion of the binder in the mass is between 32% and 42%. 4. Schutzmantel nach einem der vorhergehenden Ansprüche, da­durch gekennzeichnet,
daß das Petrolkoks zu 40 - 70 % aus Feinkorn (6b) einer Korngröße von bis zu 0,3 mm und im übrigen im wesentlichen aus Grobkorn (6a) einer Korngröße zwischen 0,5 und 5 mm besteht.4. Protective jacket according to one of the preceding claims, characterized in
that the petroleum coke consists of 40-70% fine grain (6b) with a grain size of up to 0.3 mm and otherwise essentially coarse grain (6a) with a grain size between 0.5 and 5 mm. 5. Schutzmantel nach einem der vorhergehenden Ansprüche, da­durch gekennzeichnet,
daß die Masse (6) von einem Aluminiumring (5) umgeben ist.5. Protective jacket according to one of the preceding claims, characterized in
that the mass (6) is surrounded by an aluminum ring (5). 6. Schutzmantel nach einem der vorhergehenden Ansprüche, da­durch gekennzeichnet,
daß das Bindemittel (6c) der Masse (6) aus Petrolpech mit einem Erweichungspunkt zwischen 110 und 120 °C, einer Dichte zwischen 1,10 und 1,25 g/cm³ und einem Verkokungs­wert zwischen 35 und 50 % besteht.6. Protective jacket according to one of the preceding claims, characterized in that
that the binder (6c) of the mass (6) consists of petroleum pitch with a softening point between 110 and 120 ° C, a density between 1.10 and 1.25 g / cm³ and a coking value between 35 and 50%. 7. Schutzmantel nach einem der vorhergehenden Ansprüche, da­durch gekennzeichnet,
daß die Masse an der Oberfläche mit einer Sinterhaut (6d) überzogen ist.7. Protective jacket according to one of the preceding claims, characterized in
that the mass on the surface is covered with a sintered skin (6d).
EP89123755A 1989-01-17 1989-12-22 Protector sleeve for current supply elements Expired - Lifetime EP0378842B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE8900473U 1989-01-17
DE8900473U DE8900473U1 (en) 1989-01-17 1989-01-17 Protective sheath for power supply elements

Publications (2)

Publication Number Publication Date
EP0378842A1 true EP0378842A1 (en) 1990-07-25
EP0378842B1 EP0378842B1 (en) 1993-04-28

Family

ID=6835119

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89123755A Expired - Lifetime EP0378842B1 (en) 1989-01-17 1989-12-22 Protector sleeve for current supply elements

Country Status (4)

Country Link
EP (1) EP0378842B1 (en)
DE (2) DE8900473U1 (en)
ES (1) ES2040975T3 (en)
NO (1) NO179048C (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6159603A (en) * 1995-12-15 2000-12-12 Norsk Hydro Asa Method for the use of material containing carbon in the electrolytic production of aluminium
DE10300444A1 (en) * 2003-01-07 2004-07-22 Corus Aluminium Voerde Gmbh Collar protecting connection between anode and suspension used in electrolytic cells manufacturing aluminum, comprises dense, fired carbonaceous material

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0197887A1 (en) * 1985-03-06 1986-10-15 Alusuisse-Lonza Services Ag Protector sleeve
DE3538220A1 (en) * 1985-10-26 1987-04-30 Gliemeroth Georg Dr Ing Collar packing composition

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH406650A (en) * 1958-04-22 1966-01-31 Ardal Og Sunndal Verk Process for making binders for use in the manufacture of carbonaceous electrodes
BE788602A (en) * 1971-09-10 1973-01-02 Cindu Chemie Bv WERKWIJZE TER BEREIDING VAN ELEKTRODENPEKKEN
DE2308971A1 (en) * 1973-02-23 1974-09-05 Sigri Elektrographit Gmbh Carbon or graphite article prodn. - from hard pitch contg. filler and thermosetting resin binder mixt.
US4086156A (en) * 1974-12-13 1978-04-25 Exxon Research & Engineering Co. Pitch bonded carbon electrode
DE2547061B2 (en) * 1975-10-21 1978-06-08 Kaiser-Preussag Aluminium Gmbh & Co, Voerde, 4223 Voerde Device for protecting power supply pins on anode carbons for the fused-salt electrolysis of aluminum
CH625560A5 (en) * 1977-12-16 1981-09-30 Alusuisse
DE3418663A1 (en) * 1984-05-19 1985-11-21 Rütgerswerke AG, 6000 Frankfurt Process for preparing an electrode binder
DE3533106A1 (en) * 1985-09-17 1987-03-26 Ruetgerswerke Ag ELECTRODE BINDING AGENT
DE3702720A1 (en) * 1987-01-30 1988-08-11 Bergwerksverband Gmbh CARBONED PECH MATERIAL, METHOD FOR THE PRODUCTION THEREOF AND USE OF THE PECH MATERIAL
DE3702935A1 (en) * 1987-01-31 1988-08-11 Zschimmer & Schwarz Gmbh & Co Additive for carbon-containing ceramic compositions

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0197887A1 (en) * 1985-03-06 1986-10-15 Alusuisse-Lonza Services Ag Protector sleeve
DE3538220A1 (en) * 1985-10-26 1987-04-30 Gliemeroth Georg Dr Ing Collar packing composition

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6159603A (en) * 1995-12-15 2000-12-12 Norsk Hydro Asa Method for the use of material containing carbon in the electrolytic production of aluminium
DE10300444A1 (en) * 2003-01-07 2004-07-22 Corus Aluminium Voerde Gmbh Collar protecting connection between anode and suspension used in electrolytic cells manufacturing aluminum, comprises dense, fired carbonaceous material

Also Published As

Publication number Publication date
NO900016D0 (en) 1990-01-04
ES2040975T3 (en) 1993-11-01
NO900016L (en) 1990-07-18
NO179048C (en) 1996-07-24
NO179048B (en) 1996-04-15
DE58904216D1 (en) 1993-06-03
EP0378842B1 (en) 1993-04-28
DE8900473U1 (en) 1990-05-23

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