EP0073729A1 - Stirring equipment for the dispersion of gas during the treatment of metal baths - Google Patents
Stirring equipment for the dispersion of gas during the treatment of metal baths Download PDFInfo
- Publication number
- EP0073729A1 EP0073729A1 EP82420123A EP82420123A EP0073729A1 EP 0073729 A1 EP0073729 A1 EP 0073729A1 EP 82420123 A EP82420123 A EP 82420123A EP 82420123 A EP82420123 A EP 82420123A EP 0073729 A1 EP0073729 A1 EP 0073729A1
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- Prior art keywords
- gas
- bath
- channels
- passage
- liquid
- 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.)
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- 239000006185 dispersion Substances 0.000 title claims abstract description 18
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 17
- 239000002184 metal Substances 0.000 title claims abstract description 17
- 238000011282 treatment Methods 0.000 title claims abstract description 17
- 238000003756 stirring Methods 0.000 title description 2
- 229910001338 liquidmetal Inorganic materials 0.000 claims abstract description 13
- 239000007788 liquid Substances 0.000 claims description 17
- 229910045601 alloy Inorganic materials 0.000 abstract description 5
- 239000000956 alloy Substances 0.000 abstract description 5
- 229910052782 aluminium Inorganic materials 0.000 abstract description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 abstract description 3
- 239000007789 gas Substances 0.000 description 49
- 239000000203 mixture Substances 0.000 description 5
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 239000000460 chlorine Substances 0.000 description 3
- 229910052801 chlorine Inorganic materials 0.000 description 3
- 238000004581 coalescence Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229910002804 graphite Inorganic materials 0.000 description 3
- 239000010439 graphite Substances 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 230000002411 adverse Effects 0.000 description 2
- 229910052786 argon Inorganic materials 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000005192 partition Methods 0.000 description 2
- 210000003462 vein Anatomy 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000002051 biphasic effect Effects 0.000 description 1
- 230000009172 bursting Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000009749 continuous casting Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000004945 emulsification Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 239000011872 intimate mixture Substances 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000011369 optimal treatment Methods 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000003380 propellant Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
Images
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D1/00—Treatment of fused masses in the ladle or the supply runners before casting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/20—Mixing gases with liquids
- B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
- B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
- B01F23/2331—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
- B01F27/05—Stirrers
- B01F27/11—Stirrers characterised by the configuration of the stirrers
- B01F27/111—Centrifugal stirrers, i.e. stirrers with radial outlets; Stirrers of the turbine type, e.g. with means to guide the flow
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
- B01F27/80—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis
- B01F27/81—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis the stirrers having central axial inflow and substantially radial outflow
-
- 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
- C22B21/00—Obtaining aluminium
- C22B21/06—Obtaining aluminium refining
- C22B21/066—Treatment of circulating aluminium, e.g. by filtration
-
- 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
-
- 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
- C22B9/055—Refining by treating with gases, e.g. gas flushing also refining by means of a material generating gas in situ while the metal is circulating, e.g. combined with filtration
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D27/00—Stirring devices for molten material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/20—Mixing gases with liquids
- B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
- B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
- B01F23/2331—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements
- B01F23/23311—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements through a hollow stirrer axis
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/20—Mixing gases with liquids
- B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
- B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
- B01F23/2331—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements
- B01F23/23314—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements through a hollow stirrer element
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/20—Mixing gases with liquids
- B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
- B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
- B01F23/2335—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the direction of introduction of the gas relative to the stirrer
- B01F23/23352—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the direction of introduction of the gas relative to the stirrer the gas moving perpendicular to the axis of rotation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
- B01F27/05—Stirrers
- B01F27/11—Stirrers characterised by the configuration of the stirrers
- B01F27/115—Stirrers characterised by the configuration of the stirrers comprising discs or disc-like elements essentially perpendicular to the stirrer shaft axis
Definitions
- the present invention relates to a rotary gas dispersion device for the treatment of a bath of liquid metal and, in particular, of aluminum and its alloys.
- the first consists in passing the liquid metal through inert or active filtration media which retain the impurities either mechanically, chemically or by exerting the two effects;
- the second way resorts to the use of inert or reactive gases or their mixtures, which are more or less intensely stirred with the liquid metal, in the presence or not of products such as fluxes.
- gases are injected in the form of small discrete bubbles by means of a device consisting of a rotary shaft secured to a finned rotor, of a fixed sleeve surrounding said shaft and connected at its lower end to a stator with fins: shaft and sleeve are separated by an axial passage in which the gases are transported then introduced at the level of the fins where they are subdivided into small bubbles and brought into contact with the metal stirred by the rotor.
- each gas bubble emitted can be small at the time of its formation, and give rise initially and locally to the formation of a fine dispersion, on the other hand, during its progress in the bath, it grows rapidly by coalescence with other bubbles and then forms a coarse dispersion.
- the liquid-gas exchange is considerably reduced for the parts of the bath which have not been in contact with the gas at its point of emission, hence the random effectiveness of the treatment.
- it is necessary to find a system in which each of the elementary volumes of the liquid constituting the whole of the bath to be treated, can form with the gas this desired fine dispersion in order to obtain optimum efficiency.
- This rotary gas dispersing device for the treatment of a bath of liquid metal contained in a container comprises a cylinder-shaped rotor equipped with vanes plunging into the bath, connected to a hollow drive shaft serving to supply gas, and is characterized in that the rotor is pierced with pairs of channels, each couple comprising a channel which is used for the passage of the liquid and the other, for the passage of the gas, each of these couples opening separately at the same point of the lateral surface of the cylinder so that a fine dispersion of liquid-gas is formed there, which is then distributed in the bath by means of paddles.
- the device according to the invention therefore comprises known elements, namely a cylinder-shaped rotor equipped on its side wall with pallets having any contour, placed symmetrically with respect to the axis of rotation and arranged either vertically or obliquely so as to form a helix with steps up or down.
- This rotor is connected, in its center, and in the direction of its axis, to the lower part of a drive shaft whose upper end is connected, via a speed reducer, with a motor which gives it a rotational movement.
- This shaft is hollow, so as to bring to the rotor a gas admitted at its upper end by means, for example, of a pipe provided with a rotating joint.
- this shaft is composed of two different materials: one, for the part which plunges into the bath and which is generally graphite, the other, for the emerging part and which can be a corrosion-resistant metal alloy when the treatment gas contains chlorine for example.
- This part of the shaft can be provided with cooling fins to avoid any excessive rise in temperature, which would adversely affect the performance of the equipment relating to the gas supply, and to the drive mechanism.
- the particularity of the device lies in the presence, at the inside of the rotor, most often made of graphite, of pairs of gas circulation channels and metal circulation channels drilled in the mass and arranged in an original manner.
- liquid metal circulation channels they generally have an oblique direction relative to the axis of the rotor and pass through the latter from side to side, originating either on its lower face or on its upper face, and opening onto the lateral face, at the precise place where the gas circulation pipes open. This direction is generally tilted between 10 and 60 degrees from the horizontal.
- Their section, generally circular, is greater than that of the gas channels, and also varies according to the flow rate of metal which it is desired to treat, but a diameter of between 0.5 and 1.5 cm is perfectly suitable.
- each gas channel is associated a liquid channel, from where a set of pairs of channels having a common point of emergence in the bath.
- the liquid metal moves in the channels which are intended for it. This movement takes place from bottom to top or from top to bottom depending on whether the liquid channels arise on the lower or upper face of the rotor.
- the flow rate obtained is a function of the speed of rotation of the rotor, the number of channels, their section, their inclination relative to the vertical, the difference in level between their ends and the distance between where they take birth and the center of the rotor.
- the mixture thus produced appearing on the lateral surface of the rotor is distributed immediately by means of paddles throughout the bath where the exchange reactions continue, and before coalescence occurs, the magnification of the gas bubbles and their bursting at the bath surface.
- the liquid flow rate Due to the numerous parameters which influence the liquid flow rate, it is always possible to adjust these to certain values so as to obtain a complete treatment of all the flow rate of the metal to be treated. Likewise, the gas flow rate can be adjusted to values commonly accepted for the treatment of a given quantity of metal. Thanks to these possibilities of adjusting the geometric parameters indicated above, it is possible to limit oneself to low rotational speeds, which has the advantage of simplifying the technology of the drive mechanism and thus improving the resistance in the material time.
- Such a device according to the invention can be placed in any container whose content is to be treated, whether it is a ladle, a holding or processing oven operating continuously or not, whether or not it is equipped with intermediate partitions, whether it involves flows or not, whether the gases used are nitrogen, argon, chlorine, or their mixtures, or vapors of halogenated derivatives, or any other gaseous product capable of having a favorable action on the purification of the metal.
- the flow to be treated the desired duration of the treatment, several devices can be used, whether they are placed on a single or several containers placed in series or in parallel.
- FIG. 1 there is a hollow drive shaft (1) by which the gas (2) is brought to the level of the rotor (3) by means of a chamber (4) provided at its periphery with channels ( 5) which open at (6) at the precise location where the channels (7) which originated in this case on the underside of the rotor terminate and supplying the liquid so as to form the fine liquid-gas dispersion which is then dispersed in the bath by the paddles (8).
- FIG 3 there is shown a ladle (9) closed by a cover (10), divided into an upstream compartment (11) and a downstream compartment (12) by a partition (13) supplied with liquid by the chute 'inlet (14) and drained by the outlet chute (15).
- the liquid is subjected to the action of the device according to the invention, on which we can distinguish the rotor (3) provided with its channels (5) and (7) opening into the bath at (6) and pallets (8), connected via the chamber (4) to the hollow shaft composed of a graphite part (1), sleeved at its upper part on a metal shaft (16) equipped with cooling fins (17) driven by a reduction gear (18) controlled by a motor (19) and connected to a pipe (20) by means of a rotary joint (21) in order to be able to admit gas (2) from an external source.
- the liquid enters the channels (7) in the directions (22), rises to (6) where it meets the gases admitted into the chamber (4) in the directions (23 ) which escape through the channels (5) to form a fine dispersion which is distributed in the bath by the pallets (8) in the direction (24).
- the present invention is illustrated by the following application example: a pocket 60 cm in diameter and 1 m high has been fitted with a graphite rotor having a diameter of 20 cm and a height of 8 cm.
- the rotor is provided with eight channels for the passage of metal with a diameter of 1 cm, with a length of 7 cm, inclined with respect to the vertical of 45 ° and with eight channels for the passage of gas, drilled horizontally, and with a diameter of 0.1 cm.
- the alloy was very gaseous, and presented in the vacuum test under a pressure of 2 Torr, a hydrogen content of 0.85 cc / 100 g; at the outlet, by subjecting this alloy to the same test, there was only a content of 0.14 cc / 100 g and no appearance of bubbles, which shows the effectiveness of the treatment obtained by means of the claimed device.
- the present invention finds its application whenever a good dispersion in two-phase liquid-gas mixtures is sought: this is the case in the treatment of liquid metals and, in particular, aluminum or its alloys with a view to '' remove hydrogen and non-metallic impurities.
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Abstract
Description
La présente invention est relative à un dispositif rotatif de dispersion de gaz pour le traitement d'un bain de métal liquide et, notamment, d'aluminium et de ses alliages.The present invention relates to a rotary gas dispersion device for the treatment of a bath of liquid metal and, in particular, of aluminum and its alloys.
L'homme de l'art sait qu'avant de procéder à la mise en forme de produits métallurgiques semi-finis, il est nécessaire de traiter le métal brut d'élaboration pour le débarrasser des gaz dissous et des impuretés non métalliques qu'il contient, et dont la présence nuirait aux propriétés souhaitées et à la facilité de solidification des pièces fabriquées.Those skilled in the art know that before proceeding to the shaping of semi-finished metallurgical products, it is necessary to treat the raw metal of preparation to rid it of dissolved gases and non-metallic impurities which it contains, the presence of which would adversely affect the desired properties and the ease of solidification of the parts produced.
Deux voies principales de traitement sont connues actuellement : la première consiste à faire passer le métal liquide à travers des milieux de filtration inertes ou actifs qui retiennent les impuretés soit mécaniquement, soit chimiquement, soit en exerçant les deux effets ; la deuxième voie recourt à l'utilisation de gaz inertes ou réactifs ou de leurs mélanges, lesquels sont brassés plus ou moins intensément avec le métal liquide, en présence ou non de produits tels que des flux. Ces deux voies peuvent, d'ailleurs, être combinées entre elles.Two main ways of treatment are currently known: the first consists in passing the liquid metal through inert or active filtration media which retain the impurities either mechanically, chemically or by exerting the two effects; the second way resorts to the use of inert or reactive gases or their mixtures, which are more or less intensely stirred with the liquid metal, in the presence or not of products such as fluxes. These two routes can, moreover, be combined together.
Suivant la deuxième voie, de nombreuses réalisations ont été faites portant, entre autres, sur la manière d'introduire le gaz dans le bain de métal, et sur la façon d'obtenir une meilleure dispersion des gaz dans le liquide, sachant que l'efficacité du traitement est liée à la surface interfaciale entre les deux phases.According to the second path, many achievements have been made relating, inter alia, to the way of introducing the gas into the metal bath, and to the way of obtaining a better dispersion of the gases in the liquid, knowing that the effectiveness of the treatment is linked to the interfacial surface between the two phases.
C'est ainsi que, dans le brevet français n°1.555.953, le gaz est amené dans le bain par un plongeur dont la partie inférieure est équipée d'un dispositif rotatif assurant le brassage et la répartition du gaz à travers une grande surface du bain.Thus, in French patent n ° 1.555.953, the gas is brought into the bath by a plunger whose lower part is equipped with a rotary device ensuring the mixing and the distribution of the gas through a large surface of the bath.
Dans le brevet français n°2.063.916, le gaz est insufflé dans le métal fondu au moyen d'une lance à double enveloppe refroidie par eau.In French Patent No. 2,063,916, the gas is blown into the molten metal by means of a water-cooled double-casing lance.
Dans le brevet français n°2.166.014, on injecte des gaz sous forme de petites bulles discrètes au moyen d'un dispositif constitué d'un arbre rotatif solidaire d'un rotor à ailettes, d'un manchon fixe entourant ledit arbre et relié à son extrémité inférieure à un stator à ailettes : arbre et manchon sont séparés par un passage axial dans lequel les gaz sont transportés puis introduits au niveau des ailettes où ils sont subdivisés en petites bulles et amenés en contact avec le métal agité par le rotor.In French patent n ° 2.166.014, gases are injected in the form of small discrete bubbles by means of a device consisting of a rotary shaft secured to a finned rotor, of a fixed sleeve surrounding said shaft and connected at its lower end to a stator with fins: shaft and sleeve are separated by an axial passage in which the gases are transported then introduced at the level of the fins where they are subdivided into small bubbles and brought into contact with the metal stirred by the rotor.
Dans le brevet français n°2.200.364, le gaz est introduit au centre de rotation d'un agitateur à turbine et mis en contact avec le métal liquide dans des conditions d'agitation évitant toute émulsification.In French Patent No. 2,200,364, the gas is introduced into the center of rotation of a turbine agitator and brought into contact with the liquid metal under stirring conditions avoiding any emulsification.
De nombreuses autres solutions ont encore été proposées visant à introduire le gaz sous forme de bulles très petites. Toutefois, si chacune d'elles présente des avantages spécifiques, toutes ont l'inconvénient de ne conduire qu'à une dispersion irrégulière des bulles de gaz dans le métal liquide.Many other solutions have also been proposed aiming to introduce the gas in the form of very small bubbles. However, if each of them has specific advantages, all of them have the drawback of only leading to an irregular dispersion of the gas bubbles in the liquid metal.
En effet, si chaque bulle de gaz émise peut être petite au moment de sa formation, et donner lieu initialement et localement à la formation d'une dispersion fine, par contre, au cours de son cheminement dans le bain, elle grossit rapidement par coalescence avec d'autres bulles et forme alors une dispersion grossière. L'échange liquide-gaz se trouve singulièrement réduit pour les parties du bain n'ayant pas été en contact avec le gaz à son point d'émission, d'où une efficacité aléatoire du traitement. Comme on ne peut échapper à ce phénomène de coalescence, il est nécessaire de trouver un système dans lequel chacun des volumes élémentaires du liquide constituant l'ensemble du bain à traiter, puisse former avec le gaz cette dispersion fine souhaitée pour obtenir une efficacité optimum.Indeed, if each gas bubble emitted can be small at the time of its formation, and give rise initially and locally to the formation of a fine dispersion, on the other hand, during its progress in the bath, it grows rapidly by coalescence with other bubbles and then forms a coarse dispersion. The liquid-gas exchange is considerably reduced for the parts of the bath which have not been in contact with the gas at its point of emission, hence the random effectiveness of the treatment. As one cannot escape this coalescence phenomenon, it is necessary to find a system in which each of the elementary volumes of the liquid constituting the whole of the bath to be treated, can form with the gas this desired fine dispersion in order to obtain optimum efficiency.
C'est pourquoi la demanderesse a cherché et mis au point un dispositif rotatif de dispersion de gaz pour le traitement de bain de métal liquide, de forme simple et, donc, de réalisation facile et robuste avec lequel l'ensemble du bain, circulant entre l'entrée et la sortie du récipient qui le contient, est résolu en une série de veines liquides sur lesquelles le gaz exerce, de façon continue, son effet de pénétration, de sorte que toute la masse du liquide connaisse, à à un moment du traitement cet état de dispersion fine biphasique liquide-gaz.This is why the applicant has sought and developed a rotary gas dispersion device for the treatment of a liquid metal bath, of simple shape and, therefore, of easy and robust construction with which the whole of the bath, circulating between the inlet and the outlet of the container which contains it, is resolved into a series of liquid veins on which the gas exerts, in a continuous way, its effect of penetration, so that the entire mass of the liquid knows, at a time of the treatment, this state of fine biphasic liquid-gas dispersion.
Ce dispositif rotatif de dispersion de gaz pour le traitement d'un bain de métal liquide contenu dans un récipient comprend un rotor en forme de cylindre équipé de palettes plongeant dans le bain, relié à un arbre d'entraînement creux servant à l'amenée de gaz, et est caractérisé en ce que le rotor est percé de couples de canaux, chaque couple comprenant un canal qui sert au passage du liquide et l'autre, au passage du gaz, chacun de ces couples débouchant séparément en un même point de la surface latérale du cylindre de manière qu'en cet endroit, il se forme une dispersion fine de liquide-gaz, laquelle est ensuite répartie dans le bain au moyen des palettes.This rotary gas dispersing device for the treatment of a bath of liquid metal contained in a container comprises a cylinder-shaped rotor equipped with vanes plunging into the bath, connected to a hollow drive shaft serving to supply gas, and is characterized in that the rotor is pierced with pairs of channels, each couple comprising a channel which is used for the passage of the liquid and the other, for the passage of the gas, each of these couples opening separately at the same point of the lateral surface of the cylinder so that a fine dispersion of liquid-gas is formed there, which is then distributed in the bath by means of paddles.
Le dispositif suivant l'invention comprend donc des éléments connus, à savoir un rotor en forme de cylindre équipé sur sa paroi latérale de palettes ayant un contour quelconque, placées symétriquement par rapport à l'axe de rotation et disposées, soit verticalement, soit obliquement de manière à former une hélice a pas vers le haut ou vers le bas. Ce rotor est relié, en son centre, et dans la direction de son axe, à la partie inférieure d'un arbre d'entraînement dont l'extrémité supérieure est en relation, par l'intermédiaire d'un réducteur de vitesse, avec un moteur qui lui communique un mouvement de rotation.The device according to the invention therefore comprises known elements, namely a cylinder-shaped rotor equipped on its side wall with pallets having any contour, placed symmetrically with respect to the axis of rotation and arranged either vertically or obliquely so as to form a helix with steps up or down. This rotor is connected, in its center, and in the direction of its axis, to the lower part of a drive shaft whose upper end is connected, via a speed reducer, with a motor which gives it a rotational movement.
Cet arbre est creux, de façon à amener au niveau du rotor un gaz admis à son extrémité supérieure au moyen, par exemple, d'une conduite munie d'un joint tournant. De préférence, cet arbre est composé de deux matériaux différents : l'un, pour la partie qui plonge dans le bain et qui est généralement du graphite, l'autre, pour la partie émergente et qui peut être un alliage métallique résistant à la corrosion lorsque le gaz de traitement contient du chlore par exemple. Cette partie de l'arbre peut être pourvue d'ailettes de refroidissement pour éviter toute élévation de température trop importante, qui nuirait à la tenue de l'équipement relatif à l'amenée de gaz, et au mécanisme d'entraînement.This shaft is hollow, so as to bring to the rotor a gas admitted at its upper end by means, for example, of a pipe provided with a rotating joint. Preferably, this shaft is composed of two different materials: one, for the part which plunges into the bath and which is generally graphite, the other, for the emerging part and which can be a corrosion-resistant metal alloy when the treatment gas contains chlorine for example. This part of the shaft can be provided with cooling fins to avoid any excessive rise in temperature, which would adversely affect the performance of the equipment relating to the gas supply, and to the drive mechanism.
La particularité du dispositif réside dans la présence, à l'intérieur du rotor, le plus souvent en graphite, de couples de canaux de circulation de gaz et de canaux de circulation de métal percés dans la masse et disposés de manière originale.The particularity of the device lies in the presence, at the inside of the rotor, most often made of graphite, of pairs of gas circulation channels and metal circulation channels drilled in the mass and arranged in an original manner.
Ainsi, en ce qui concerne les premiers, ils sont placés radialement et se rejoignent tous au centre du rotor en un endroit directement en relation avec la partie creuse de l'arbre ou par l'intermédiaire d'une chambre. Ils débouchent tous dans le bain sur la paroi latérale du cylindre, de préférence, entre deux palettes. Leur section, généralement circulaire, est petite et varie en fonction de la pression du gaz utilisé et du débit de gaz qu'on désire faire passer, mais on peut de préférence choisir des diamètres compris entre 0,1 et 0,4 cm.Thus, with regard to the first, they are placed radially and all meet at the center of the rotor at a location directly in relation to the hollow part of the shaft or through a chamber. They all lead into the bath on the side wall of the cylinder, preferably between two pallets. Their section, generally circular, is small and varies according to the pressure of the gas used and the gas flow rate which it is desired to pass, but it is preferably possible to choose diameters between 0.1 and 0.4 cm.
Quant aux canaux de circulation de métal liquide, ils ont généralement une direction oblique par rapport à l'axe du rotor et traversent ce dernier de part en part, prenant naissance soit sur sa face inférieure, soit sur sa face supérieure, et débouchant sur la face latérale, à l'endroit précis où débouchent les canalisations de circulation de gaz. Cette direction est inclinée généralement entre 10 et 60 degrés par rapport à l'horizontale. Leur section, généralement circulaire, est supérieure à celle des canaux de gaz, et varie également en fonction du débit de métal que l'on désire traiter, mais un diamètre compris entre 0,5 et 1,5 cm convient parfaitement.As for the liquid metal circulation channels, they generally have an oblique direction relative to the axis of the rotor and pass through the latter from side to side, originating either on its lower face or on its upper face, and opening onto the lateral face, at the precise place where the gas circulation pipes open. This direction is generally tilted between 10 and 60 degrees from the horizontal. Their section, generally circular, is greater than that of the gas channels, and also varies according to the flow rate of metal which it is desired to treat, but a diameter of between 0.5 and 1.5 cm is perfectly suitable.
Le nombre de canaux des deux types étant le même, à chaque canal de gaz est associé un canal de liquide, d'où un ensemble de couples de canaux ayant un point commun d'émergence dans le bain.The number of channels of the two types being the same, with each gas channel is associated a liquid channel, from where a set of pairs of channels having a common point of emergence in the bath.
En fonctionnement, sous l'effet de la force centrifuge engendrée par la rotation, le métal liquide se déplace dans les canaux qui lui sont destinés. Ce déplacement s'effectue de bas en haut ou de haut en bas suivant que les canaux de liquide prennent naissance sur la face inférieure ou supérieure du rotor. Le débit obtenu est fonction de la vitesse de rotation du rotor, du nombre de canaux, de leur section, de leur inclinaison par rapport à la verticale, de la différence de niveau entre leurs extrémités et de la distance entre l'endroit où ils prennent naissance et le centre du rotor.In operation, under the effect of the centrifugal force generated by the rotation, the liquid metal moves in the channels which are intended for it. This movement takes place from bottom to top or from top to bottom depending on whether the liquid channels arise on the lower or upper face of the rotor. The flow rate obtained is a function of the speed of rotation of the rotor, the number of channels, their section, their inclination relative to the vertical, the difference in level between their ends and the distance between where they take birth and the center of the rotor.
Lorsque la liaison de l'arbre creux avec une source de gaz sous pression est établie, on provoque dans les canaux de gaz l'apparition d'un flux qui, en raison de la faible section de ces derniers, con- - duit à des vitesses très grandes à l'endroit où les veines de liquide débouchent dans le bain. Il en résulte alors une dispersion fine des deux phases et un mélange intime entre le gaz et le métal sur toute la section de sortie du canal de liquide.When the connection of the hollow shaft with a source of gas under pressure is established, the gas channels cause the appearance of a flow which, due to the small cross section of the latter, - leads to very high speeds at the point where the veins of liquid open into the bath. This then results in a fine dispersion of the two phases and an intimate mixture between the gas and the metal over the entire outlet section of the liquid channel.
Le mélange ainsi produit apparaissant à la surface latérale du rotor est réparti immédiatement au moyen des palettes dans tout le bain où se poursuivent les réactions d'échange, et avant que se produise, par coalescence le grossissement des bulles de gaz et leur éclatement à la surface du bain.The mixture thus produced appearing on the lateral surface of the rotor is distributed immediately by means of paddles throughout the bath where the exchange reactions continue, and before coalescence occurs, the magnification of the gas bubbles and their bursting at the bath surface.
En raison de nombreux paramètres qui influent sur le débit de liquide, il est toujours possible d'ajuster ceux-ci à certaines valeurs de façon à obtenir un traitement complet de tout le débit du métal à traiter. De même, on peut ajuster le débit de gaz à des valeurs communément admises pour le traitement d'une quantité de métal donné. Grâce à ces possibilités d'ajustement des paramètres géométriques indiquées ci-dessus, on arrive à se limiter à des vitesses de rotation faibles, ce qui a pour avantage de simplifier la technologie du mécanisme d'entraînement et d'améliorer ainsi la tenue dans le temps du matériel.Due to the numerous parameters which influence the liquid flow rate, it is always possible to adjust these to certain values so as to obtain a complete treatment of all the flow rate of the metal to be treated. Likewise, the gas flow rate can be adjusted to values commonly accepted for the treatment of a given quantity of metal. Thanks to these possibilities of adjusting the geometric parameters indicated above, it is possible to limit oneself to low rotational speeds, which has the advantage of simplifying the technology of the drive mechanism and thus improving the resistance in the material time.
On conçoit l'intérêt d'un tel dispositif par rapport aux autres propulseurs de gaz proposés jusqu'à maintenant, car en plus du brassage par les palettes, on a un renouvellement continu et complet de la masse de métal à traiter, à l'endroit précis où on injecte le gaz de traitement. D'où une surface d'échange gaz-liquide maximale, et par suite, une efficacité optimale du traitement.We can see the advantage of such a device compared to the other gas propellants proposed up to now, because in addition to mixing by the pallets, there is a continuous and complete renewal of the mass of metal to be treated, at precise location where the process gas is injected. Hence a maximum gas-liquid exchange surface, and therefore, optimal treatment efficiency.
Un tel dispositif selon l'invention peut être placé dans tout récipient dont on veut traiter le contenu, que ce soit une poche de coulée, un four de maintien ou d'élaboration fonctionnant en continu ou non, qu'il soit équipé ou non de cloisons intermédiaires, qu'il mette en jeu des flux ou non, que les gaz utilisés soient de l'azote, de l'argon, du chlore, ou leurs mélanges, ou des vapeurs de dérivés halogénés, ou tout autre produit gazeux susceptible d'avoir une action favorable sur la purification du métal.Such a device according to the invention can be placed in any container whose content is to be treated, whether it is a ladle, a holding or processing oven operating continuously or not, whether or not it is equipped with intermediate partitions, whether it involves flows or not, whether the gases used are nitrogen, argon, chlorine, or their mixtures, or vapors of halogenated derivatives, or any other gaseous product capable of having a favorable action on the purification of the metal.
Suivant le traitement désiré, le débit à traiter, la durée souhaitée du traitement, on peut utiliser plusieurs dispositifs, qu'ils soient mis en place sur un seul ou plusieurs récipients placés en série ou en parallèle.Depending on the desired treatment, the flow to be treated, the desired duration of the treatment, several devices can be used, whether they are placed on a single or several containers placed in series or in parallel.
L'invention sera mieux comprise à l'aide des dessins ci-joints, qui n'ont d'autre but que d'illustrer et non de limiter la portée de la présente demande.The invention will be better understood with the aid of the attached drawings, which have no other purpose than to illustrate and not to limit the scope of the present application.
- La figure 1 représente une coupe verticale du dispositif suivant un plan passant par l'axe de rotation et les axes de deux couples de canaux.Figure 1 shows a vertical section of the device along a plane passing through the axis of rotation and the axes of two pairs of channels.
- La figure 2 représente, vue de dessous, une coupe horizontale suivant le tracé X'X de la figure 1, du dispositif.2 shows, seen from below, a horizontal section along the line X'X of Figure 1, of the device.
- La figure 3 représente, en coupe verticale, le dispositif installé sur une poche de coulée en continu.Figure 3 shows, in vertical section, the device installed on a continuous casting ladle.
Sur la figure 1, on distingue un arbre d'entraînement (1) creux par lequel le gaz (2) est amené au niveau du rotor (3) par l'intermédiaire d'une chambre (4) pourvue à sa périphérie de canaux (5) qui débouchent en (6) à l'endroit précis où aboutissent les canaux (7) ayant pris naissance dans le cas présent sur la face inférieure du rotor et amenant le liquide de manière à former la dispersion fine liquide-gaz qui est ensuite dispersée dans le bain par les palettes (8).In FIG. 1, there is a hollow drive shaft (1) by which the gas (2) is brought to the level of the rotor (3) by means of a chamber (4) provided at its periphery with channels ( 5) which open at (6) at the precise location where the channels (7) which originated in this case on the underside of the rotor terminate and supplying the liquid so as to form the fine liquid-gas dispersion which is then dispersed in the bath by the paddles (8).
Sur la figure 2, on voit en (1) l'extrémité inférieure de l'arbre creux à l'endroit où il se raccorde sur la chambre (4) du rotor (3) percé des canaux (5) servant au passage du gaz, qui débouchent dans le bain en (6) au même endroit que les canaux qui servent au passage du liquide et où la dispersion fine liquide-gaz est répartie dans le bain par les palettes (8).In FIG. 2, we see in (1) the lower end of the hollow shaft at the place where it is connected to the chamber (4) of the rotor (3) pierced with channels (5) serving for the passage of the gas , which open into the bath in (6) at the same place as the channels which serve for the passage of the liquid and where the fine liquid-gas dispersion is distributed in the bath by the pallets (8).
Sur la figure 3, est représentée une poche de coulée (9) fermée par un couvercle (10), partagée en un compartiment amont (11) et un compartiment aval (12) par une cloison (13) alimentée en liquide par la goulotte d'entrée (14) et vidangée par la goulotte de sortie (15).In Figure 3, there is shown a ladle (9) closed by a cover (10), divided into an upstream compartment (11) and a downstream compartment (12) by a partition (13) supplied with liquid by the chute 'inlet (14) and drained by the outlet chute (15).
Au cours de son passage dans la poche entre (14) et (15), le liquide est soumis à l'action du dispositif selon l'invention, sur lequel on peut distinguer le rotor (3) muni de ses canaux (5) et (7) débouchant dans le bain en (6) et des palettes (8), raccordé par l'intermédiaire de la chambre (4) à l'arbre creux composé d'une partie en graphite (1), manchonnée à sa partie supérieure sur un arbre métallique (16) équipé d'ailettes de refroidissement (17) entraîné par un réducteur (18) commandé par un moteur (19) et relié à une tuyauterie (20) par l'intermédiaire d'un joint tournant (21) afin de pouvoir admettre le gaz (2) en provenance d'une source extérieure.During its passage through the pocket between (14) and (15), the liquid is subjected to the action of the device according to the invention, on which we can distinguish the rotor (3) provided with its channels (5) and (7) opening into the bath at (6) and pallets (8), connected via the chamber (4) to the hollow shaft composed of a graphite part (1), sleeved at its upper part on a metal shaft (16) equipped with cooling fins (17) driven by a reduction gear (18) controlled by a motor (19) and connected to a pipe (20) by means of a rotary joint (21) in order to be able to admit gas (2) from an external source.
Au cours de la rotation du dispositif, le liquide pénètre dans les canaux (7) suivant les directions (22), s'élève jusqu'en (6) où il rencontre les gaz admis dans la chambre (4) suivant les directions (23) qui s'échappent par les canaux (5) pour former une dispersion fine qui est répartie dans le bain par les palettes (8) suivant la direction (24).During the rotation of the device, the liquid enters the channels (7) in the directions (22), rises to (6) where it meets the gases admitted into the chamber (4) in the directions (23 ) which escape through the channels (5) to form a fine dispersion which is distributed in the bath by the pallets (8) in the direction (24).
La présente invention est illustrée par l'exemple d'application suivant : une poche de 60 cm de diamètre et de 1 m de haut a été équipée d'un rotor en graphite ayant un diamètre de 20 cm et une hauteur de 8 cm.The present invention is illustrated by the following application example: a pocket 60 cm in diameter and 1 m high has been fitted with a graphite rotor having a diameter of 20 cm and a height of 8 cm.
Le rotor est muni de huit canaux servant au passage du métal de diamètre 1 cm, de longueur 7 cm, inclinés par rapport à la verticale de 45° et de huit canaux servant au passage du gaz, percés horizontalement, et d'un diamètre de 0,1 cm.The rotor is provided with eight channels for the passage of metal with a diameter of 1 cm, with a length of 7 cm, inclined with respect to the vertical of 45 ° and with eight channels for the passage of gas, drilled horizontally, and with a diameter of 0.1 cm.
On a fait circuler dans la poche six tonnes par heure d'un alliage d'aluminium du type 2014. Le rotor tournait à la vitesse de cent cinquante tours par minute et l'on a injecté 4 Nm3/h d'un mélange argon 95% chlore 5% en volume.One circulated in the pocket six tons per hour of an aluminum alloy of the type 2014. The rotor turned at the speed of one hundred and fifty revolutions per minute and one injected 4 Nm 3 / h of an argon mixture 95%
A l'entrée de la poche, l'alliage était très gazeux, et présentait au test de vide sous une pression de 2 Torr, une teneur en hydrogène de 0,85 cc/100 g ; à la sortie, en soumettant cet alliage au même test,on ne notait plus qu'une teneur de 0,14 cc/100 g et aucune apparition de bulles, ce qui montre l'efficacité du traitement obtenu au moyen du dispositif revendiqué.At the entry of the pocket, the alloy was very gaseous, and presented in the vacuum test under a pressure of 2 Torr, a hydrogen content of 0.85 cc / 100 g; at the outlet, by subjecting this alloy to the same test, there was only a content of 0.14 cc / 100 g and no appearance of bubbles, which shows the effectiveness of the treatment obtained by means of the claimed device.
La présente invention trouve son application chaque fois que l'on cherche une bonne dispersion dans les mélanges biphasiques liquide-gaz : c'est le cas dans le traitement des métaux liquides et, notamment, de l'aluminium ou de ses alliages en vue d'éliminer l'hydrogène et les impuretés non métalliques.The present invention finds its application whenever a good dispersion in two-phase liquid-gas mixtures is sought: this is the case in the treatment of liquid metals and, in particular, aluminum or its alloys with a view to '' remove hydrogen and non-metallic impurities.
Claims (7)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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AT82420123T ATE12311T1 (en) | 1981-08-28 | 1982-08-25 | STIRRER FOR GAS INTRODUCTION IN METAL BATH TREATMENT. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8116735A FR2512067B1 (en) | 1981-08-28 | 1981-08-28 | ROTARY GAS DISPERSION DEVICE FOR THE TREATMENT OF A LIQUID METAL BATH |
FR8116735 | 1981-08-28 |
Publications (2)
Publication Number | Publication Date |
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EP0073729A1 true EP0073729A1 (en) | 1983-03-09 |
EP0073729B1 EP0073729B1 (en) | 1985-03-20 |
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Application Number | Title | Priority Date | Filing Date |
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EP82420123A Expired EP0073729B1 (en) | 1981-08-28 | 1982-08-25 | Stirring equipment for the dispersion of gas during the treatment of metal baths |
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US (1) | US4426068A (en) |
EP (1) | EP0073729B1 (en) |
JP (1) | JPS6049700B2 (en) |
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AT (1) | ATE12311T1 (en) |
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BG (1) | BG41825A3 (en) |
BR (1) | BR8205026A (en) |
CA (1) | CA1184381A (en) |
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DE (1) | DE3262681D1 (en) |
DK (1) | DK158325C (en) |
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ES (1) | ES8307914A1 (en) |
FR (1) | FR2512067B1 (en) |
GR (1) | GR77611B (en) |
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SU (1) | SU1233807A3 (en) |
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EP0162789A1 (en) * | 1984-04-06 | 1985-11-27 | Servimetal | Installation for the treatment of steel by injection of gas before continuous casting |
FR2562449A1 (en) * | 1984-04-06 | 1985-10-11 | Servimetal | DEVICE FOR TREATING STEEL, BEFORE CONTINUOUS CASTING, BY GAS INJECTION |
EP0183402A2 (en) * | 1984-11-29 | 1986-06-04 | Foseco International Limited | Rotary device, apparatus and method for treating molten metal |
EP0183402A3 (en) * | 1984-11-29 | 1986-09-03 | Foseco International Limited | Rotary device, apparatus and method for treating molten metal |
FR2604099A1 (en) * | 1986-09-22 | 1988-03-25 | Pechiney Aluminium | ROTATING DEVICE WITH PELLETS FOR SOLUTION OF ALLOY ELEMENTS AND DISPERSION OF GAS IN AN ALUMINUM BATH |
EP0262058A1 (en) * | 1986-09-22 | 1988-03-30 | Aluminium Pechiney | Rotating devices having blades for dissolving alloy elements and for dispersing gas in a bath of aluminium |
WO1990001985A1 (en) * | 1988-08-16 | 1990-03-08 | Dieter Gabor | Device for treating fluid to thin-bodied media |
US5292194A (en) * | 1988-08-16 | 1994-03-08 | Dieter Gabor | Device for preparing liquid to thin pulpy media |
EP0365013A3 (en) * | 1988-10-21 | 1991-10-23 | Showa Aluminum Kabushiki Kaisha | Device for releasing and diffusing bubbles into liquid |
EP0365013A2 (en) * | 1988-10-21 | 1990-04-25 | Showa Aluminum Kabushiki Kaisha | Device for releasing and diffusing bubbles into liquid |
US5087292A (en) * | 1989-04-11 | 1992-02-11 | L'Air Liquide, Societe Anonyme pour l'Etude et l Exploitation des Procedes Georges Claude | Process and apparatus for treating a liquid with a gas |
EP0392900A1 (en) * | 1989-04-11 | 1990-10-17 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Process and apparatus for the treatment of a liquid with a gas |
FR2645456A1 (en) * | 1989-04-11 | 1990-10-12 | Air Liquide | PROCESS AND PLANT FOR TREATING A LIQUID WITH A GAS |
EP0408165A1 (en) * | 1989-07-10 | 1991-01-16 | The Carborundum Company | Dispersing gas into molten metal |
FR2656001A1 (en) * | 1989-12-18 | 1991-06-21 | Pechiney Recherche | METHOD AND DEVICE FOR PRODUCING METALLIC MATRIX COMPOSITE PRODUCTS |
EP0438004A1 (en) * | 1989-12-18 | 1991-07-24 | PECHINEY RECHERCHE (Groupement d'Intérêt Economique régi par l'Ordonnance du 23 Septembre 1967) Immeuble Balzac | Method and device for making composite products having a metal matrix |
EP0665198A1 (en) * | 1994-01-27 | 1995-08-02 | Foseco International Limited | Impact resistant oxidation protection for graphite parts |
US5656236A (en) * | 1994-02-04 | 1997-08-12 | Alcan International Limited | Apparatus for gas treatment of molten metals |
EP0900853A1 (en) * | 1994-02-04 | 1999-03-10 | Alcan International Limited | Rotary impeller for gas treatment of molten metals |
US5593634A (en) * | 1994-02-04 | 1997-01-14 | Alcan International Limited | Gas treatment of molten metals |
US5527381A (en) * | 1994-02-04 | 1996-06-18 | Alcan International Limited | Gas treatment of molten metals |
WO1995021273A1 (en) * | 1994-02-04 | 1995-08-10 | Alcan International Limited | Gas treatment of molten metals |
US5660614A (en) * | 1994-02-04 | 1997-08-26 | Alcan International Limited | Gas treatment of molten metals |
WO1997011034A1 (en) * | 1995-09-22 | 1997-03-27 | Bernhard Van Dyk | Submersible mixing impeller |
AU708143B2 (en) * | 1995-09-22 | 1999-07-29 | Bernhard Van Dyk | Submersible mixing impeller |
US6126150A (en) * | 1995-09-22 | 2000-10-03 | Van Dyk; Bernhard | Submersible mixing impeller |
WO1998005915A1 (en) * | 1996-08-02 | 1998-02-12 | Pechiney Rhenalu | Rotary gas dispersion device for treating a liquid aluminium bath |
US6060013A (en) * | 1996-08-02 | 2000-05-09 | Pechiney Rhenalu | Rotary gas dispersion device for treating a liquid aluminium bath |
WO1999034024A1 (en) * | 1997-12-24 | 1999-07-08 | Alcan International Limited | Injector for gas treatment of molten metals |
US6056803A (en) * | 1997-12-24 | 2000-05-02 | Alcan International Limited | Injector for gas treatment of molten metals |
CN111102850A (en) * | 2019-12-26 | 2020-05-05 | 河北工业职业技术学院 | Automatic material homogenizing device for metal smelting |
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