DE1598540C

DE1598540C - Device for determining the activity, in particular of oxygen, in metallic baths

Info

Publication number: DE1598540C
Authority: DE
Inventors: Hans Jürgen Prof. Dr. rer. nat. 7000 Stuttgart; Schulte Eberhard Dr.-Ing. 4600 Dortmund. G06f 7-38 Engell
Original assignee: Hoesch AG
Current assignee: Hoesch AG
Publication date: 1971-12-16

Description

1 21 2

Die Erfindung betrifft eine Vorrichtung zur trolyten aus dem Schutzrohr bewirkte räumlicheThe invention relates to a device for trolytes brought about from the protective tube spatial

Bestimmung der Aktivität, insbesondere von Sauer- Trennung der wirksamen Kontaktstelle des Elek-Determination of the activity, in particular of acid separation of the effective contact point of the elec-

stoff in metallischen Bädern. In neuerer Zeit ist man trolyten, das ist die freie Stirnseite des Elektrolyten,fabric in metallic baths. In recent times one is trolyten, that is the free face of the electrolyte,

bemüht, sich von den konventionellen Methoden von dem Schutzrohr, vermeidet die Ausbildung einertries to move away from the conventional methods of the protective tube, avoids the formation of a

zur Bestimmung von Elementen, insbesondere von 5 Reaktionskette Schutzrohr—Schmelze—Elektrolyt,for the determination of elements, in particular of 5 reaction chain protection tube - melt - electrolyte,

Sauerstoff, in metallischen Bädern zu lösen. Vor die das Meßergebnis verfälschen würde,Oxygen, to be dissolved in metallic baths. In front of which the measurement result would be falsified,

allem die bislang gebräuchlichen Sauerstoffbestim- Eine solche Vorrichtung ermöglicht es ohne wei-all the oxygen determinations that have been used up to now.

mungen lassen zu wünschen übrig, da diese Be- teres, ausschließlich die Aktivitäten von in demComments leave a lot to be desired, since these are better things to do exclusively with the activities of in the

Stimmungen, wie auch die entsprechenden Bestim- schmelzflüssigen Metall befindlichen Sauerstoff undMoods, as well as the corresponding determining- molten metal and oxygen

mungen anderer Elemente, eine im Hinblick auf io solchen Elementen, die mit Sauerstoff in einemother elements, one with regard to io those elements which combine with oxygen in one

den Arbeitsablauf in Schmelzbetrieben zu lange Zeit definierten Zusammenhang stehen, zu ermitteln. Austhe workflow in smelting plants are related for too long a time. Out

beanspruchen. Insbesondere bei der Ermittlung des den so ermittelten eindeutigen Werten lassen sichclaim. In particular when determining the unambiguous values determined in this way,

Sauerstoffgehaltes mindert die für die Bestimmung die tatsächlichen Gehalte der interessierendenOxygen content reduces the actual content of those of interest for the determination

erforderliche Zeit den Aussagewert der Bestimmung, Elemente ohne weiteres herleiten. Die auf dieserequired time to derive the informative value of the determination, elements without further ado. The on this

da sich gerade die Sauerstoffgehalte in metallischen 15 Weise mögliche, eindeutige Schnellbestimmung vonsince it is precisely the oxygen content in a metallic 15 possible, clear rapid determination of

Bädern laufend ändern. Außerdem läßt die Genauig- Elementen, insbesondere von Sauerstoff, ist vonChange baths continuously. In addition, the Precision elements, especially oxygen, are of

keit der bekannten Analysenverfahren bei kleinen großem Nutzen bei der Überwachung und Steuerungability of the known analytical methods with small, large benefits in monitoring and control

Gehalten zu wünschen übrig. metallurgischer Prozesse.Kept much to be desired. metallurgical processes.

Die Suche nach einer zeitunabhängigen Bestim- In der Patentschrift Nr. 21 673 des Amtes für mungsmethode, insbesondere zur Bestimmung des 20 Erfindungs- und Patentwesen in Ost-Berlin ist zwar Augenblicksgehaltes von Sauerstoff in metallischen schon eine Vorrichtung zur Durchführung von Gas-Bädern, hat zur Einführung der elektrochemischen analysen bei erhöhten Temperaturen mit Hilfe gal-Aktivitätenermittlung geführt. Die Ermittlung von vanischer Feststoffelektrolytelemente vorgeschlagen Aktivitäten in wäßrigen Lösungen mit Hilfe einer worden, bei der ein kompakter Elektrolyt in einem galvanischen Kette ist seit langem bekannt. Durch 25 Trägerrohr gelagert ist. In diesem Falle ist aber einen Kunstgriff ist es ermöglicht worden, ent- weder eine Abdichtung des Inneren des Trägerrohres sprechende Ermittlungen in metallischen Bädern vorgesehen noch eine räumliche Trennung der freien durchzuführen, indem man nämlich das schmelz- Stirnseite des Elektrolyten von dem Trägerrohr,
flüssige Metall zur Elektrode macht, in die ein hoch- Es sind verschiedene Ausführungsformen des temperaturbeständiger Elektrolyt im Kontakt mit 30 Elektrolyten und des ihn umgebenden Schutzrohres einer Vergleichselektrode eintaucht, von der ein . möglich. Bei der Auswahl geeigneter Stoffe, wie auch Spannungsmeßgerät beaufschlagt wird, das an das bei der Formgebung, ist den beim Einsatz auftretenmetallische Bad angeschlossen ist. Es werden jedoch den Beanspruchungen, wie sie insbesondere durch auf diese Weise bei technischen Metallbädern noch die schroffen Temperaturwechsel ausgelöst werden, keine einwandfreien Werte, insbesondere was die 35 Rechnung zu tragen.The search for a time-independent determination In patent no. 21 673 of the Office for mung method, in particular to determine the 20 invention and patent system in East Berlin, although the instantaneous content of oxygen in metallic already has a device for carrying out gas baths led to the introduction of electrochemical analyzes at elevated temperatures with the help of gal activity determination. The determination of vanic solid electrolyte elements has been proposed using an activity in aqueous solutions, in which a compact electrolyte in a galvanic chain has long been known. Is supported by 25 support tube. In this case, however, a trick has been made possible to either seal the interior of the support tube for determining determinations in metallic baths or to carry out a spatial separation of the free ones, namely by removing the melting end face of the electrolyte from the support tube,
There are various embodiments of the temperature-resistant electrolyte in contact with the electrolyte and the protective tube surrounding it of a comparison electrode, from which a. possible. In the selection of suitable materials, as well as a voltage measuring device is applied, which is connected to the metal bath that occurs during the shaping process. However, the stresses that are triggered in this way in technical metal baths, in particular, by the abrupt temperature changes, are not flawless values, especially those that have to be taken into account.

Aktivität des Sauerstoffes betrifft, ermittelt, da als Für den betriebllichen Einsatz hat sich eine VorFehlerquellen die über dem Metallbad befindliche richtung als zweckmäßig erwiesen, bei der ein sich Gasphase und gegebenenfalls auch die das Metallbad eintauchseitig konisch verjüngendes Schutzrohr vorbedeckende Schlacke das Meßergebnis beeinflussen. gesehen ist, in dem der Elektrolyt in Form eines Die Schlacke beeinflußt gegebenenfalls auch die 4° konischen Stopfens unter Federdruck in seiner End-Ermittlung der Aktivität anderer Elemente. Außer- lage gehalten wird. Es ist natürlich auch möglich, dem zerstört die Schlacke die Meßanordnung. den Elektrolyten in das Schutzrohr einzuschmelzen.Activity of the oxygen concerns, determined, since as for the operational use has a pre-sources of error the direction located above the metal bath proved to be useful, in which a Gas phase and optionally also the protective tube that tapers conically in front of the metal bath on the immersion side Slag influence the measurement result. is seen in which the electrolyte is in the form of a The slag may also influence the 4 ° conical plug under spring pressure in its final determination the activity of other elements. Is held out of position. It is of course also possible the slag destroys the measuring arrangement. to melt the electrolyte in the protective tube.

Der Erfindung liegt einerseits die Aufgabe zu- Dazu ist es zweckmäßig, die Innenwandung desThe invention is on the one hand the task to- To this end, it is appropriate to the inner wall of the

gründe, den in das Metallbad eintauchenden Elek- Schutzrohres auszukehlen.reasons to groove the electrical protective tube immersed in the metal bath.

trolyten gegen Schlacke bzw. Atmosphäre abzu- 45 Insbesondere bei der Verwendung von Elektrolytschirmen und auf diese Weise die störende Beein- werkstoffen mit einem gegenüber dem Schutzrohr flussung durch diese Medien auszuschalten, und höheren Ausdehnungskoeffizienten erweist sich eine andererseits die Aufgabe, eine Verfälschung des Ausführungsform als zweckmäßig, bei der ein ein-Meßergebnisses durch die Reaktionskette Schutz- tauchseitig eingezogenes Schutzrohr und ein auf dem rohr—Schmelze—Elektrolyt zu vermeiden. 50 eingezogenen Rand des Rohres in dem Rohr mitTrolytes to protect against slag or atmosphere, especially when using electrolyte screens and in this way the disruptive interfering materials with one opposite the protective tube Eliminate flow through these media, and a higher coefficient of expansion turns out to be on the other hand, the task of falsifying the embodiment as expedient in the case of a one-measurement result through the reaction chain, protective tube drawn in on the immersion side and a protective tube on the Avoid pipe-melt-electrolyte. 50 retracted edge of the tube in the tube with

Die Aufgaben werden erfindungsgemäß mit einer Spiel lagernder, in feuerfester Masse . eingebetteterAccording to the invention, the tasks are performed with a game that is stored in a refractory mass. embedded

Vorrichtung zur Bestimmung der Aktivität, insbeson- Stopfen mit einem aus dem Rohr herausragendenDevice for determining the activity, in particular a stopper with a protruding from the tube

dere von Sauerstoff in metallischen Bädern, wobei Ansatz vorgesehen ist. Vorteilhafterweise ist dermore of oxygen in metallic baths, whereby approach is provided. Advantageously, the

das metallische Bad eine Elektrode darstellt, in die Stopfen im wesentlichen kugelförmig ausgebildet,the metallic bath represents an electrode in which the plugs are essentially spherical,

ein in einem feuerfesten, nicht ionenleitenden Schutz- 55 Die Vergleichselektrode, die mit dem Elektrolytenone in a fireproof, non-ion-conductive protective 55 The comparison electrode that contains the electrolyte

rohr angeordneter hbchtemperaturbeständiger Elek- in unmittelbarem Kontakt stehen muß, wird in wei-must be in direct contact with the high-temperature-resistant elec-

trolyt in Kontakt mit einer Vergleichselektrode ein- terer Ausgestaltung der Erfindung gebildet durchtrolyte in contact with a comparison electrode of a first embodiment of the invention formed by

taucht, von der ein Spannungsmeßgerät beaufschlagt einen die Verbindung zwischen dem Elektrolytendips, from which a voltmeter acts on the connection between the electrolyte

wird, das an das metallische Bad angeschlossen ist, und dem Spannungsmeßgerät herstellenden Drahtconnected to the metallic bath and the tension meter making wire

gelöst, die dadurch gekennzeichnet ist, daß der Elek- ⁶° aus ionenleitendem, hochhitze- und chemisch bestän-which is characterized achieved in that the electron ⁶ ° of ionically conductive, highly heat and chemical bestän-

trolyt aus dem Schutzrohr unter Abdichtung des- digem Material, beispielsweise aus einem Platindraht,trolyt from the protective tube with sealing of the material, for example from a platinum wire,

selben nach außen begrenzt herausragt. in Verbindung mit einem bei der Meßtemperatursame protrudes limited to the outside. in connection with one at the measuring temperature

Das Schutzrohr schirmt den bei der Messung in flüssigen oder gasförmigen Sauerstoffträger mitThe protective tube also shields the oxygen carrier when measuring in liquid or gaseous form

das Metallbad eintauchenden Elektrolyten gegen konstantem Sauerstoff-Partialdruck. Der gasförmigeElectrolytes immersed in the metal bath against constant oxygen partial pressure. The gaseous one

Schlacke bzw. Atmosphäre ab. Die Abdichtung stellt 65 Sauerstoffträger durchströmt dabei zweckmäßiger-Slag or atmosphere. The seal provides 65 oxygen carriers.

sicher, daß kein schmelzflüssiges Metall in das Innere weise das den Elektrolyten umgebende und abschir-make sure that no molten metal gets into the interior of the electrolyte surrounding and shielding

des die Vergleichselektrode enthaltenden Schutz- mende Schutzrohr als Spülmedium,the protective tube containing the reference electrode as flushing medium,

rohres dringt. Die durch das Herausragen des Elek- Für den betrieblichen Einsatz ist es erforderlich,pipe penetrates. Due to the protrusion of the elec- For operational use it is necessary

Claims

3 43 4

that the parts of the device that continuously outgaseous oxygen carriers 16 have to be changed immediately, that is, the electrolyte is in contact with the electrolyte 13 and the protective tube, easy and quick to install, comparison electrode 14, 16. The measuring line 15 also proved can be dismantled. This object is achieved by a voltmeter 17 which, in a further embodiment of the invention, is indirectly connected to the metallic bath 21 in that the protective tube is placed in a manner known per se, namely via a contact with the metallurgical vessel 19, into a reference electrode carrying the reference electrode Holding magnets 18, is connected.
Measuring lance or the like over the comparison electrode. Further details of the immersion head, which can be screwed in from the electrolyte and the comparison electrode, can be seen from FIG. 2 through FIG. 1. The protective tube 12, as a rule, creates a clamp connection. One made of quartz tapers on the immersion side so that, according to the advantageous embodiment, the electrolyte 13, formed as a conical stopper, remains attached to the clamp connection through the twisted central protruding into an end protective tube 12, which is provided in the electrolyte on the side. On the inside of the electrolyte bore, the end of the comparison electrode has a central bore 23, into which the twisted end of a ceramic two-hole bead 24 connects with the aid of the electrode and the voltmeter. To twist the line end 26 of the connecting line 14 is inserted. If one expediently uses a clearance of free space, the connection line 14 is mixed with a two-hole bead. This type of connection is additionally shielded by a guide tube 27, which avoids any contact between the reference electrode and 20, which prevents the forced circulation of the protective tube fed from above. gaseous oxygen carrier 16 is effected.

It is of course also possible to use a protective tube, electrolyte The seat of the electrolyte 13 in the protective tube 12

trolyt and reference electrode to a lost, can additionally be secured by resilient means

head which can be attached to the measuring lance, as shown for example in FIG.

to understand. This is the component that compares 25 is.

Oxygen carriers forming the electrode are more useful - Figs. 4a and 4b show in the protective tubes 31, 31 '

wisely melted into the lost head. In the melted electrolyte 32, 32 '.

lost head can also be the connection contact for According to Fig. 5 is in the protective tube 33

the molten metal voltmeter arranged electrolyte 34 in refractory mass 36.

be included. In this case, there are 30 beds on the connection side.

one connector each for connecting the device. Apart from a solution according to FIG. 1

the same electrode and the connection contact for this, of course, other constructive solutions are possible.

Provide a voltage measuring device. Another possibility. So the connection contact for .the Span-

possibility, the voltage measuring device to the metallic voltage measuring device be a diving contact. Diving contact

To connect the bath is the one to which the molten 35 and electrolyte can also be in one and the same

Metal-containing containers, for example a diving head, can be combined. A corresponding

Mold to put a holding magnet, which is with the corresponding solution in F i g. 6 shown. It is

Voltmeter is conductively connected. a dip head 41 made of refractory material

In the event that the electrolyte is seen through a, in which a comparison electrode is used in the Slag cover introduced into the metal bath 40 measuring temperature of gaseous or liquid oxygen must, a fusible, the free carrier 43 and one in contact with the Elek end of the electrolyte or the entire immersion head trolyte 42 standing platinum wire 44 melted shielding sheath be provided. is, in such a way that the electrolyte 42 includes

Embodiments according to the invention are immersed in the shielded oxygen carrier 43

45 in the drawing projects out of the immersion head 41 in a very schematic manner. component

placed. It shows the diving head 41 is also the connection

F i g. 1 an embodiment of the device contact 46 for the voltage measuring device, from which

according to the invention in use, the immersion head 41 protruding end

F i g. 2 shows the broken diving head from FIG. 1 moderately by a nozzle 47 made of refractory

on a larger scale, 5 ° material is shielded. Electrolyte 42 and connection

Fig. 3 is an embodiment of the electrolyte contact46 for protection against the action

with protective tube, the slag through a meltable shell 48

Fig. 4a, 4b, 5 further embodiments of the screened.

Electrolyte with protective tube, ^ patent claims:

F1 g. 6 a modified embodiment of the 55th

Device according to the invention. 1. Device for determining the activity,

In Fig. 1, 19 is a metallurgical vessel in particular of oxygen in metallic

in which there is a bath covered with slag 22, the metallic bath being an elec-

metallic bath 21 is located. trode represents, in the one in a refractory,

A protective tube arranged by a non-ion-conductive 60 is immersed in the metallic bath 21

In a measuring lance 11 screwed protective tube 12 high temperature resistant electrolyte in contact

against the slag 22 and the atmosphere above which is immersed with a comparison electrode from which

Melt 21, 22 is shielded, held and acted upon by a tension measuring device that

led electrolyte 13, for example from with CaO is connected to the metallic bath, d a -

stabilized ZrO. ,, a. A 65 made of platinum is characterized in that the elec-

Connection line 14, which the electrolyte 13 with trolyte (13, 32, 32 ', 34) from the protective tube (12,

a measuring line 15 connects, forms together with 31, 3Γ, 33) with sealing of the same

one inserted from above into the protective tube 12 protrudes to a limited extent on the outside. .

2. Apparatus according to claim 1, characterized in that the protective tube (12) is immersion side conically tapered, and that the electrolyte (13) has the shape of a conical plug which is held in its end position under spring pressure will.

3. Apparatus according to claim 1, characterized in that the protective tube (33) is immersed is drawn in, and that the electrolyte (34) embedded in a refractory mass (36) and with provided a projection protruding from the tube in the tube on the retracted Edge of the same with play superimposed.

4. Apparatus according to claim 3, characterized in that the in the protective tube (33) is located Part of the electrolyte (34) is essentially spherical.

5. Apparatus according to claim 1, characterized in that the electrolyte (32, 32 ') in the Protective tube (31, 31 ') is melted.

6. Apparatus according to claim 5, characterized in that the inner wall of the protective tube (31, 31 ') for receiving the electrolyte (32, 32') is grooved on the immersion side.

7. Device according to claims 1 to 6, characterized by a clamp connection between the electrolyte and the reference electrode.

8. Apparatus according to claim 7, characterized in that the electrolyte has a bore (23) in which the twisted end (26) of the comparison electrode (14,16) with the voltmeter (17) connecting measuring line (15) is inserted.

9. Device according to claims 1 to 6, characterized in that the protective tube (12), the electrolyte (13) and the comparison electrode (14, 16) are combined to form a unit, which can be plugged onto a measuring lance (11).

10. The device according to claim 9, characterized in that that the immersion head (41), which consists of the protective tube, the electrolyte and the reference electrode, has one connection contact (46) is provided for the voltmeter, and one connector each for the Connection of the comparison electrode and the connection contact to the voltmeter is provided is.

11. Device according to claims 1 to 9, characterized by a holding magnet (18) for connecting the voltmeter to the metal bath (21) containing the vessel (19). .

12. Device according to claims 1 to 11, characterized in that the free end of the Electrolytes (13, 32, 32 ', 34, 42) or the immersion head (41) from a fusible shell (48) is surrounded.

1 sheet of drawings