LU86541A7 - Metallic melt mixing and treating vessel - has electromagnets to turn the melt up into raised part where it drops back to the melt surface and additives are added - Google Patents

Abstract

When metal melts are treated by the addn. of chemically active substances or alloying elements, the metal melt is kept in motion in a suitable vessel of cylindrical shape by electromagnetic forces. The melt fills at least half of the vessel and is raised by a rotational movement around the horizontal axis to the apex and drops back on the surface of the melt near the axis. Mechanism forces can be used to assist the inductive mixing action.

Description

/ - -f A 809 R h h fl 1 GRAND-DUCHÉ DE LUXEMBOURG; Certification N * ............. I *! you ......... whether üiï. ........... ffÿito Monsieur le Ministre 1 .... de l’Économie et des Classes Moyennes

Titre délivré ......................................... Service de la Propriété Intellectuelle

g- ^ LUXEMBOURG

Demande de Brevet d'invention

Certificat d’addition au brevet d'invention no 86.469; _ ______________________________________________________________________________________du 12 juin 1986 I. Requête

Monsi.eur ..... Pn.ul .... MEIZ .................................. .................................................. .................................................. ............................................. (1) lg, ... "xue ..... J. *. E ....... Brasseur, ...... L ..... r ...... 125.8 .... .LUXEMBOURG ................................................ ................................

reprê. £ en.tâ .... par ..... Me.ssie.ur5 ..... l! iEYJE] ii .. „ile.n.é .., ...... ingénieur .................................................. .......... (2) ..................................... .................................................. ............... LEITZ Paul, ...... engineer ......................... ................................................

Jgs dépose (nt) ce ..ci.nq.-aQÛt ~ -19.Û.Û jq.ua.txe .-. Ving t - .. s.ia ............. ............................................ (3) à .. ............ heures, au Ministère de l'Économie et des Classes Moyennes, à Luxembourg: 1. la présente requête pour l'obtention d'un brevet d'invention concernant:

Process and device for treating molten metals_____________ 2. la délégation de pouvoir, .....- requis-e ................. le .......... ...............................................

3. la description en langue ..al-leffiande .................................. de l'invention en deux exemplaires; 4. ............ 6 ................. planches de dessin, en deux exemplaires; 5. la quittance des taxes versées au Bureau de l'Enregistrement à Luxembourg, le ....... jQ.S ..... ao.û.t ..... 1.9..8.6 .... .................................................. .................................................. .................................................. ......................................

déclare (nt) en assumant la responsabilité de cette déclaration, que l ’(es) inventeurs) est (sont): _______________________________ (5)

Mons.iaur .-. E.aul .... ME.TZ _____________________________________________________________________________________________________________________________________________________________ 18 * rua- J ·, P · Brasseur · ----------------------- -------------------------------------------------- -------------------------------------------------- ------------------ L ... - .... 1..2S-8-LUXEMBQU.RG ............ .......... λ ____________________________________________________________________________________________________________% revendiquent) pour la susdite demande de brevet la priorité d'une (des) demande (s) de (6) ___________________________________________________________________________ déposée (s) en (7) ___________________________________________________________________________ ie ---- -------------------------------------------------- -------------- m au nom de ................................ ....................................... ___________________________________________________________________________ _____________________________________________ <8) élit (élisent) pour lui (elle) et, si désigné, pour son mandataire, à Luxembourg_________________ .A.RBED .... S..A .... J .....- A-. -G, -3 ...... GasePosta.le .... 1-802, ...... L -......- 2930 ..... LUXEMBOURG ------ ---------- (10) solIicite (nt) la délivrance d'un brevet d'invention pour l'objet décrit et représenté dans les annexes sjKsmentionnée ^^ - avec ajournement de cette délivrance à .... ........ 1S ........................................ mois . (11)

Le ..M £ Ma ± aix.a / ^ __________________ LEITZyPaul ^ II. Procès-verbal de Dépôt

La susdite demande de brevet d’invention a été déposée au Ministère de l’Économie et des Classes Moyennes, Service de la Propriété Intellectuelle à Luxembourg, en date du: À / '' /? 'Pr. Lj | Ministre à / y g heures de l’Économie et ^ s Classes Moyennes, »î. * - / A 809

Patent application

Additional application to the Luxembourg patent application No. 86,469

Applicant: Mr. Paul METZ

18, rue J. P. Brasseur L-1258 Luxembourg

Method and device for treating molten metals j

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Method and device for treating molten metals

The main patent describes a method or a device for treating metal melts by introducing solids or gases, in which the melt is rotated in an essentially horizontal, elongated vessel by means of electromagnetic force, such that the melt moves around the horizontal vessel axis is lifted, the metal preferably falling back onto the surface of the bath to which the said solids or gases have been applied by gravity in the direction of the vessel axis by gravity.

Since the registration of the main patent, further research has led to significant improvements in the registered subject. At first it was found that the method according to the invention also for the treatment of metal baths with liquids e.g. premelted slag is best suited.

Furthermore, it was found that the angle of inclination of the vessel lying lengthwise was an important factor. With such a system, the most varied of reactions can be carried out, be it in cocurrent or in countercurrent, a combination of the two also being possible.

25 It is known that counter current operations can be performed with conventional electromagnetic troughs. However, it has been found that this method of working can usually only achieve an insufficient mixing effect. In contrast, the method and the device according to the invention allow implementation i j. 1 "* ^ - 2 - * very energetic reactions with simultaneous application of the principles of countercurrent metallurgy.

As already explained in the main patent, one can achieve a backward movement of the less conductive substances with horizontal mixing vessels, if one designs the inductor (s) in such a way that they produce a helical mixing and rotating movement. In most cases, however, it is appropriate to design the device with a certain inclination in order to accelerate the countercurrent reaction. This tendency depends on the reaction rate and should be adjustable between 0 and 20 0, at least in test plants. At different treatment stages, it is advisable to give the same channel several inclinations, parts of such a channel in the form of conventional electromagnetic transport channels being able to be used.

If several process stages are connected in series, it is necessary to separate the process stages from one another by means of siphon devices in order in this way to achieve the most complete intermediate slag removal possible.

Fig. 1 shows the diagram of a channel system which desiplicates, dephosphorized and desulfurized at the same time. She understands 3 siphons S1, S2 and S3, with 3 siphon walls la, 2a and 3a, as well as 3 mixing sections 25 lb, 2b and 2c. Such a system can be used in the blast furnace channel between the blast furnace and the transport ladle, but it can also be used as an intermediate ladle element between the torpedo ladle and the steelworks ladle. The pig iron R is tipped, for example, from a pig iron pan into the siphon device la, from where the 30 slag can flow out through the opening 4a. After the siphon wall S1 has been crossed, the pig iron is detected by an electromagnetic mixing device according to the invention 1b and conveyed into the siphon device S2 on the basis of a helical arrangement of the inductors over an incline OC = 5 °. Before this siphon 35 is reached, preheated mill scale with flux W is fed in, which flows back in countercurrent in the direction of the siphon S1 and largely removes the pig iron. This route is either acidic or - 3 - lined with a high alumina feed. The high-silica slag is separated through the opening 4b. The pig iron falls into the siphon S2, where silicon-containing slag residues flow out through the opening 4c. After passing the siphon 5, dephosphorization takes place in the electromagnetic mixing device 2b, which has a curved shape. The lower part of this system in the area of the siphon S2 has an inclination | î> = 7 ° to the horizontal and flattens at the upper end to 2 0 where the helically arranged mixing inductors pass through on the floor and / or above the slightly inclined device be replaced by linear feed inductors. This arrangement was chosen in order to give the soda S, which was added as a dephosphoric agent in this example, the opportunity to liquefy before being transported in countercurrent to S2 where it can react and drain through the opening 4d. 15 The dephosphorization reaction is supported in the mixing device by introducing oxygen or gases containing oxygen (not shown). After extensive dephosphorization, the treated pig iron flows into the siphon device S3, where traces of slag left behind can flow out through the opening 4e. After passage of the siphon S3, the pig iron enters the horizontal or downstream (1 to 3 °) electromagnetic mixing system 2c, where calcium carbide K is added directly behind the siphon wall 3a. After leaving the device 2c, the pig iron with its desulfurization slag flows into the pan 6, where a further desulphurization can be supported by flushing gas 6a. However, the main purpose of this operation is to protect the pig iron from radiation losses through the desulfurization slag layer. In the case where you would also like to automatically remove the desulfurization slag, you would tilt the electromagnetic mixing system 2c by about 7 ° and add the calcium carbide shortly before the end of the outlet and let the slag run off in an overflow to be installed in the siphon S3. The desulfurization effect can be supported in system 2c by injecting small amounts of reducing gases.

The systems 2b and 2c are preferably to be provided with a basic lining.

35,. > · - 4 -

In addition, it was found that the effect of the electromagnetic force, which causes the rotational movement of the melt, can be increased significantly by conducting an electrical current through the axis of the metal bath to be moved. This current is advantageously introduced into the metal bath through electrodes (not shown) which are located before and after the point to be moved. The current can be three-phase or direct current, but the highest efficiency is achieved with direct current.

10 In addition, it was found that a change in the current supply to the inductors by superimposing the normal current supply with pulse currents or by brief frequency changes significantly increases the mixing effect.

15 If the main patent relates mainly to elongated furnaces, it also describes the possibility (page 3, lines 11-24) of applying the method according to the invention to other furnaces, only partial quantities being removed and returned to the furnace, or several Ovens are operated together in such a way that a continuous process is created.

A further task was therefore to describe these devices and methods, which relate on the one hand to the treatment of partial quantities and on the other hand to the use of several connected ovens 25.

Regarding a possible system for the treatment of partial quantities, we refer to FIG. 2a, which shows a top view, to FIG. 2b, which shows a frontal side view, and FIG. 2c, which combines a section with a side view.

In these three drawings, the pan or oven 1 lined with refractory contains the metal 2 which fills the pan to the N level. A slag film or slag layer S normally floats on the metal bath.

If you want to treat the metal 2 e.g. by adding desulfurizing

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As is frequently used in steel and pig iron, the device 3 is introduced into the metal bath, care being taken in most cases that the slag does not penetrate the device. After the inlet and possibly the outlet 5 of the device has been introduced into the bath, the device 3 is filled with metal. This filling can be effected by switching on the inductor (s) 5, which are designed in such a way that they exert a pumping action on the metal bath. If one wants to avoid that the inductors, which are mostly water-cooled, have to be introduced into the metal bath, these inductors can, as shown in FIG. 2c, be designed in such a way that the water-cooled inductor part 5 is located above the bath surface and the possibly air-cooled magnetic cores 5a reach below the metal level and thus convey the metal into the mixing section provided with the treatment inductors 4 15.

The treatment device 3 could also be filled using the method described in Luxembourg Patent No. 83,763.

20 The mode of operation of the inductors 4 corresponds to that which was already described in the main patent, in which case the inductors are preferably designed in such a way that they take care of conveying the metal from right to left. They can also be designed in such a way that they have a heating effect in addition to the mixing and conveying effect. At the moment when the metal reaches the inductors 4 and is set into an intimate mixing movement by these inductors, the solids or liquids or gases required for the treatment can be supplied to the metal bath through the openings or nozzles 9, 9a to 9b and 30 be intimately mixed with it.

If you want to separate the treated amount from the untreated one, you can provide the pan with a dividing wall T open at the bottom.

35 A device similar to that just described consists in that the mixing section provided with the inductors is direct, i.e. without the ascending section provided with the lifting inductor 5, with at least>. '1 * - 6 - one or two openings made in the pan and provided with slide closures, which would lead to a result similar to that previously described. Such a device leads to 5 very favorable results in tilting pans and in particular in torpedo pans. In these cases, the filling of the mixing device can be easily achieved by simply tilting the pan, whereby, with sufficient pumping and lifting action of the inductors 4, the metal could be reached by overflowing into the pans through a normal opening.

10th

The mixing section just described with direct contact with the metal, that is to say without a lifting inductor, could be attached to the device for treating molten metals before casting described in European patent application 83630074.9-2309, the heating described in this patent application being treated with a simultaneous treatment of the Metal can be treated according to the enclosed invention.

2a, 2b, 2c show a device in which the metal to be treated is conveyed from a pan into the mixing device according to the invention by means of a magnetic pump effect.

The magnetic pump effect can be supported or replaced by other known means. Thus, as further described with the help of an example game for torpedo pans, the pig iron to be treated can be supported or replaced by overpressure in the pan, by a gas siphoning effect or by vacuum, the four means mentioned, i.e. Overpressure in the pan, gas lifting effect, vacuum, electroinductive pumping can be used alone or in combination of the 30 individual or different or all of the means mentioned.

Fig. 3 describes such a system in connection with torpedo ladles in which the desired operations such as desiliconization, desulfurization, dephosphorization can be carried out in succession.

k. * "- 7 -

In addition to its normal sprue, this torpedo pan has a second opening 2, both openings preferably being able to be closed gas-tight. If this is not possible, a partition 3 is provided, which extends approximately to the middle of the torpedo pan.

5

The device understands a riser pipe 5 which protrudes to just above the bottom of the torpedo pan and is preferably provided with a gas lift system. The upper part of the riser pipe can be provided with an intake line 6. The electromagnetic pump 10 described in FIG. 2 can also be installed in the nozzle 5. The torpedo pan itself can be subjected to a slight excess pressure, so that the pig iron fills the tube 5 and reaches the mixing section 4, or 4a and 4b. If the inlet of the torpedo pan is not easy to seal, it is sufficient to pressurize only the right part of the torpedo pan after installing the partition 3. The filling device 9, which is connected to the entire system, is inserted into the normal insertion nozzle of the torpedo pan 1. This device consists of a syphon vessel with a partition, a ladle insertion nozzle 8, and 20 a slag overflow 7. The nozzle 8 can be closed with a melting plate 9a or with a plug 9b at the beginning of the operation.

The electromagnetic mixing section 4 can pass directly from 5a to 9, as shown in dashed lines in the upper illustration of FIG. 3 and in the lower illustration of FIG. 3. However, in order to achieve a larger mixing distance, the mixing section can also take the detour 4a and 4b from 5 to 9. The mode of operation of the system as a whole, which is introduced into the torpedo pan 30 by means of a lifting and lowering device, can easily be seen from FIG. 3 and from the description which has just been given:

The pig iron to be treated is lifted via the pipe 5 with one or more of the four means described above to 5a where it is then continuously conveyed into the siphon body 9 via the mixing sections 4, or 4a and 4b with addition of 10a of the known substances or gases to be treated which, after filling and melting 8a or lifting 9b, causes the pig iron to flow back into the torpedo pan above 8 after treatment.

The slag generated during the treatment automatically drains off via 5 7, so that the treatments such as desulfurization, de-siliconization and dephosphorization can be carried out in succession.

If the mixing sections 4, or 4a and 4b have a sufficient gradient 10 e.g. Above 2 °, such that the slag is not entrained with the metal flow, it is possible to work in countercurrent, the additions being carried out in FIG. 10 and the slag running out of the nozzle 5a designed as a siphon via 7a.

15 It is possible to place the system on the right side of the pan symmetrically on the left side of the pan, whereby both systems can work together using the same siphon device 9.

20 As indicated in the illustration below, it is possible for individual torpedo pans to mount the nozzle 2 in such a way that it automatically fills with metal when the torpedo pan is tilted backwards, this metal then being fed into the mixing device via 5a and then continuing as described can. In this case 25, the four described lifting means can be bypassed.

The device just described could also be used in normal pans containing pig iron, steel or other metals.

30th

It is easy to see that with the devices just described in FIGS. 2a, 2b, 2c and 3, the most varied of metallurgical operations are possible.

35 In the case of pig iron, the desired operations, such as desilication, dephosphorization and desulfurization, can preferably be carried out successively in the same pan, e.g. Torpedo pans with the same device '_, * * * - 9 - be carried out by means known per se. The individual operations are favored by the automatic intermediate deslagging.

5 Operations such as the treatment of waste products containing zinc and lead with pig iron as described in the main patent can also be carried out in the systems described.

Steel baths can also be treated in the manner described in the production furnace 10 itself or in the casting ladle or intermediate ladle with the devices described using known means. For example, Steel baths can be easily alloyed with powdery alloy elements or with known treatment slags such as solid or liquid Perrin slags are desulfurized or deoxidized 15.

The same devices can be used for snow heating steel melts by aluminothermic. This method, which combines snow heating of the bath with a treatment effect of the 20 slag produced at the same time, was described in the Luxembourg patent No. 84 272 by the same author.

The reaction described in this process can be combined with the device according to the invention, just described under Fig. 2a, 2b or 2c, the aluminum addition e.g. can take place through the nozzle 9, and the subsequently required oxygen is introduced through the nozzles 9a and 9b. The intimate mixing which can be achieved by the device according to the invention between the steel treated with aluminum and the oxygen subsequently introduced leads to a very rapid heating effect, combined with a simultaneous cleaning effect due to the slag produced during the reaction.

For complex reactions such as in coal gasification in the raw iron bath with simultaneous desulfurization, in direct reduction with simultaneous pig iron production, or in the processes used in non-ferrous metallurgy, it is advantageous

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- 10 - drive or to use the device according to the invention as an intermediate link between two or more furnaces working in a network. This application of the invention, which is associated with great advantages, is described in more detail in the following two examples.

5

The first example is shown in Fig. 4 and relates to a coal gasification plant of coal with a relatively low sulfur content. The. System basically consists of two containers 1 and 2, which are connected in the upper part to the mixing section 4, a tube 5 10 connects the two vessels in their lower part. The system is provided with a refractory lining 3. The system is closed with the covers 6 in such a way that it can also work under pressure.

15 The vessel 1 is equipped with a lance 15, which optionally blows oxygen with lime dust onto the pig iron bath designated 9. The oxygen, possibly with added lime, can also be fed to the pig iron bath 9 through the floor nozzles 15a, which nozzles are designed as oil or gas-cooled annular gap nozzles.

20th

This supply of oxygen creates the gas by burning the carbon contained in the pig iron. The heat generated can be regulated by adding water vapor to the injected oxygen. The heat that occurs can also be used to melt scrap or pre-reduced ores which are introduced into the vessel 1 through the opening 16. Incidentally, all or part of the gases produced can be used for the pre-reduction of ores.

30 The centerpiece of the system is the upper connecting trough'4, which is designed as an electroinductive mixing device, as described in more detail in the main patent. This gutter, which naturally consists of a magnetically permeable jacket, such as Non-magnetic steel, or should advantageously consist of an non-magnetic composite material 35, is lined on the inside with a highly refractory and abrasion-resistant material. This channel should be designed in such a way that the metal 9 is conveyed from 1 to 2; to this end * . * k »- 11 - the inductor (s) 11 are designed in such a way that, in addition to their intensive mixing effect, they also promote the metal from 1 to 2. The trough has the filler neck 12 through which the carbon is introduced into the system.

5

As shown in FIG. 4, the channel can be installed in the furnace 1 in such a way that the slag, in this case a desulphurization slag, which mainly consists of lime with possibly a riverside additive, is conveyed from 1 to 2. In this way, the coal introduced by 12 is immediately associated with the premelted desulfurization slag and the pig iron, so that the pig iron is not only carburized by the carbon, but is also desulfurized.

15 According to this procedure, the volatile constituents of the coal can be discharged separately via the gas line 13 together with the valuable tars as rich gas, whereby the gas resulting from the oxygen-steam injection in 1 can be discharged via 13a. If you want to have a sharp separation of the gases, you have to 20 insert the connection and mixing tube 4 in the vessel 1 under the bath level. In this case, however, the liquid slag desulfurization effect has to be dispensed with and the desulfurization agents introduced with the coal.

25 If you only want to obtain a mixed gas, the exhaust pipe 13 is closed and all gases are discharged via 13a. The tars are then cracked in the hot gas space above the bath 9 in the vessel 1.

The slags 10 leave the system via 7 possibly together with 30 a slight excess of pig iron. Is with scrap or; cooled with pre-reduced ore, the pig iron resulting from these substances is tapped through the tap holes 8 or 14.

Since 4 pig iron is continuously conveyed from 1 to 2 35 through the mixing trough and flows back to the vessel 1 via the connecting pipe 5, the system operates continuously.

The system shown in Fig. 4 can be used for a wide variety of metallurgical work.

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This system can be used for the treatment of lead and zinc containing 5 the metallurgical waste as already described in the main patent, whereby in this system the electrical heating is replaced by carbon combustion with oxygen. In this case, the connecting piece of the mixing and conveying trough 4 is moved into the vessel 1 under the bath level N and the substances to be treated are introduced through 12, possibly with added carbon. The gases containing lead and zinc leave the system via the nozzle 13. The temperature is regulated by injecting smaller amounts of oxygen via the lance 15 and / or the floor nozzles 15a. The slag leaves, possibly with pig iron, the vessel 15 2 via the overflow 7. Pig iron can be discharged via the outlet 8 or together with lead via the outlet 14.

Fig. 5 shows schematically a plant with 3 tanks and 2 mixing sections. This plant already allows more complex treatments 20 such as e.g. Gasification of coal with a higher sulfur content and simultaneous cement production.

As in the previous example, coal 1 is gasified with oxygen and possibly water vapor in vessel 1. In the mixing section 4, the carbon 25 with lime dust is introduced through the nozzle 12 and mixed intensively with the pig iron by the described action of the inductors 11. The lime additive is calculated in such a way that the coal ash results in a composition suitable for cement production. The slag formed in this way is discharged via the channel 7, a siphon wall 6, which is interrupted at the bottom, possibly preventing this slag from being entrained into the mixing section 4a.

The main desulfurization is carried out in this mixing section 4a, whereby known desulfurization agents such as e.g. 35 soda or lime flow path mixtures are introduced and intimately mixed with the pig iron through the action of the inductors 11a. The resulting desulphurization slag is separated off via 7a, I w - 13 - whereby the pig iron flows back into the vessel 1 via 5. The amount flowing back can be controlled via the solenoid and pump valve 5a.

5 The gases or pig iron produced are removed from the system as described in FIG. 3.

In the case of even more complex metal treatments, as is customary in non-ferrous metallurgy, the number of vessels and inductive mixing channels can be increased as desired.

As shown in Fig. 5, these channels are formed as straight tubes, which, in contrast to the embodiment of Fig. 4, significantly facilitates the lining of these channels. The circular-arc-shaped channel shown in FIG. 4 could be replaced with a straight-line channel with good success.

It may not fall outside the scope of this invention e.g. in the case of coal rich in ash, the system receives additional energy e.g. in the form of electrical energy by means of induction coils or arcs.

Claims (17)

1. Process for treating molten metal by introducing solid, liquid or. gaseous substances that make you loud 2. The method according to claim 1, characterized in that the mixing section is formed by inclining the vessel or the flow-through member in the upward direction of the flow and by 20 application of the substances at the end of the mixing section causes a counterflow between the rising metal melt and the falling substance addition. 3. The method according to claims 1 and 2, characterized in that 'in the region of the mixing section, electrical current, preferably direct current, is passed through the melt. 4. The method according to claims 1-3, characterized in that a partial quantity is removed from a metallurgical vessel, this is treated in at least one mixing section and conveyed back into the same vessel. 5. The method according to claims 1-3, characterized in that a partial quantity is removed from a metallurgical vessel, treated in the mixing section and conveyed to a second vessel. ». - 2 - 5 main patent sets the melt in a suitable essentially horizontal vessel or flow element by means of electromagnetic force in a rotational movement such that the melt is lifted around the axis of the vessel or flow, the metal preferably after reaching the vessel or flow flow organ crest by gravity in the direction of the axis falls back onto the bath surface to which the said substances or gases have been applied, characterized in that, with the aid of electromagnetic means, the melt is additionally moved in the axial direction and onto it 6. The method according to claim 5, characterized in that one connects the lower parts of the two metallurgical vessels with a tube with a view to a metal circulation. 7. Process according to claims 1-3, characterized in that several metallurgical vessels are connected to one another by means of several mixing sections, with different types of metallurgical reactions being carried out in the individual vessels and mixing sections. 10th 8. The method according to claims 1-3, characterized in that one arranges several mixing sections one behind the other and carries out a specific metallurgical treatment in each mixing section, wherein siphon systems with discharge connections for removing reaction slags or exhaust gases are arranged between the individual mixing sections. 9. Device for performing the method according to claims 1 and 2, characterized in that a metallurgical vessel 20 or flow element is provided with at least one electromagnetic inductor which induces forces in the metallic content which act on the one hand transversely to the longitudinal axis and on the other hand in the axial direction . 10. The device according to claim 9, characterized in that the vessel or the flow element comprehends at least one inductor, which is arranged along the longitudinal axis. 11. The device according to claim 9, characterized in that the 30 vessel or the flow organ comprehends several inductors which are arranged helicoïdally around the longitudinal axis. 12. Device according to claims 9-11, characterized in that the power supply to the inductors includes means for 35 Superimposing the normal power supply with pulse currents or for briefly changing the current frequency. ». . ’F - 3 - 13. Device according to claims 9-12, characterized in that the flow element is arranged inclined in connection with a metal inlet and a metal outlet, the metal outlet being located at the higher level. 5 14. Device according to claims 9-13, characterized in that the flow element is designed in a straight line. 15. The device according to claims 9-13, characterized in 10 that the flow element is curved. 15 way forms a mixing section. 16. Device according to claims 9-15, characterized in that the vessel or the flow element is designed to be tiltable. 15 17. Device according to claims 9-15, characterized in that the vessel or the flow element is connected to cooperating metallurgical vessels which are themselves designed to be tiltable.