CA2811357A1 - Electrolytic cell for extracting aluminium - Google Patents
Electrolytic cell for extracting aluminium Download PDFInfo
- Publication number
- CA2811357A1 CA2811357A1 CA2811357A CA2811357A CA2811357A1 CA 2811357 A1 CA2811357 A1 CA 2811357A1 CA 2811357 A CA2811357 A CA 2811357A CA 2811357 A CA2811357 A CA 2811357A CA 2811357 A1 CA2811357 A1 CA 2811357A1
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- Prior art keywords
- electrolytic cell
- aluminium
- cathode
- cell according
- side wall
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- Abandoned
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- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 86
- 239000004411 aluminium Substances 0.000 title claims abstract description 86
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 85
- 238000000034 method Methods 0.000 claims abstract description 28
- 238000005868 electrolysis reaction Methods 0.000 claims abstract description 27
- 239000007788 liquid Substances 0.000 claims abstract description 22
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 31
- 230000008569 process Effects 0.000 claims description 26
- 238000009413 insulation Methods 0.000 claims description 5
- 239000003792 electrolyte Substances 0.000 claims description 2
- 230000001747 exhibiting effect Effects 0.000 claims 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 7
- 239000000203 mixture Substances 0.000 description 7
- 229910052799 carbon Inorganic materials 0.000 description 6
- 229910001610 cryolite Inorganic materials 0.000 description 6
- 239000000274 aluminium melt Substances 0.000 description 5
- 238000000605 extraction Methods 0.000 description 5
- 230000002349 favourable effect Effects 0.000 description 5
- 238000009626 Hall-Héroult process Methods 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000005755 formation reaction Methods 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- -1 aluminium cations Chemical class 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 239000011244 liquid electrolyte Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- KLZUFWVZNOTSEM-UHFFFAOYSA-K Aluminium flouride Chemical compound F[Al](F)F KLZUFWVZNOTSEM-UHFFFAOYSA-K 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000003993 interaction Effects 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 239000010405 anode material Substances 0.000 description 1
- RHZUVFJBSILHOK-UHFFFAOYSA-N anthracen-1-ylmethanolate Chemical compound C1=CC=C2C=C3C(C[O-])=CC=CC3=CC2=C1 RHZUVFJBSILHOK-UHFFFAOYSA-N 0.000 description 1
- 239000003830 anthracite Substances 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 239000010406 cathode material Substances 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000009970 fire resistant effect Effects 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
- C25C3/08—Cell construction, e.g. bottoms, walls, cathodes
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electrolytic Production Of Metals (AREA)
Abstract
The invention relates to an electrolysis cell for extracting aluminium from its oxide, said cell comprising a cathode (1) and a surrounding lateral wall (1a), the lateral wall (1a) being provided with a number of passages (1aa) that open up outwardly into an overflow trough (10). The invention also relates to a method for extracting aluminium from its oxide by means of molten-salt electrolysis using such an electrolysis cell. The invention ensures a continuous and homogeneous delivery of the nascent liquid aluminium.
Description
07.03.2013 Electrolytic cell for extracting aluminium The invention relates to a cathode for an electrolytic cell for extracting aluminium by fused-salt electrolysis. The invention further relates to a process for extracting aluminium by fused-salt electrolysis.
The Hall-Heroult process is currently used for the industrial extraction of aluminium from its oxide. This is an electrolytic process in which aluminium oxide (A1203) is dissolved in molten cryolite (Na3 [AlF6]) and the resulting mixture acts as a liquid electrolyte in an electrolytic cell. In principal, the design of such an electrolytic cell used to carry out the Hall-Heroult process is depicted schematically in Figures la to lc, wherein Figure 1 a shows a cross-section through a traditional cell, while Figure lb shows an external side view of the cell. Fig. lc shows a perspective view of an electrolytic cell.
Reference symbol 1 denotes a cathode, which may, for example, be made from graphite, anthracite or a mixture thereof. Alternatively, coke-based graphitised cathodes may also be used. The cathode 1 is generally embedded in a mounting 2 made from steel and/or a fire-resistant material or the like. The cathode 1 may be made in one piece as well as may be made from individual cathode blocks. Reference symbol 20 denotes the side walls of the electrolytic cell, which form a tank along with the cathode. This tank may also be regarded as the internal lining of the mounting. The side walls may also be made in one piece as well as may be made from individual blocks.
Over the entire length of the cell, a number of current supply bars 3 are introduced into the cathode 1, although only a single current supply bar 3 can be seen in the cross-sectional view in Figure la. It can be seen in Fig. lc that two current supply bars, for example, may be provided for each cathode block.
The current supply bars are used to supply the cell with the current required for the electrolytic process. There is a plurality of prismatic anodes 4 opposite the cathode 1, while two anodes 4 are depicted in Figure la. Fig. 1 c shows a SGL CARBON SE
07.03.2013 detailed configuration of anodes in an electrolytic cell. During the performance of the process, the aluminium oxide dissolved in cryolite is reduced to aluminium wherein the aluminium cations move to the molten aluminium ¨
actually the cathode from an electrochemical point of view ¨ where they accept electrons by applying a voltage between cathode 1 and anodes 4. Due to the greater density, aluminium 5 gathers in the liquid phase beneath the molten mixture 6 of aluminium oxide and cryolite. The oxygen ions are reduced to oxygen at the anode, said oxygen reacting with the carbon of the anodes.
Reference symbols 7 and 8 are the schematic representations of the negative and positive poles, respectively, of a voltage source for providing the voltage required for the electrolytic process, the value of which lies between around 3.5 and 5 V, for example.
As can be seen in the side view in Figure 1 b, the mounting 2 and therefore the entire electrolytic cell traditionally has an elongated form, in which a plurality of current supply bars 3 are conducted vertically through the side walls of the mounting 2. The longitudinal expansion of cells currently in use is typically between around 8 and 15 m, while the width expansion is around 3 to 4 m. A
cathode, as is shown here in Figure la, is disclosed in EP 1845174, for example.
The high binding energy between aluminium and oxygen and also the heat and resistance losses cause a high energy requirement when producing aluminium by fused-salt electrolysis. The associated energy costs constitute the main part of the process costs. Reducing these costs is one of the major problems that need to be overcome in the field of fused-salt electrolysis. A major factor in relation to the energy efficiency of a fused-salt electrolytic cell is the distance required between the anode and cathode or, more accurately, the distance between the anode and the molten aluminium. The greater this distance has to be, the higher is the specific energy requirement of the electrolytic cell.
The distance required between the anode and cathode is primarily determined , 07.03.2013 3 , by the magnetic field induced by the extremely high current intensities of up to approx. 500 kA, by the electromagnetic interactions and by the thereby resulting wave movements and bulges of the liquid aluminium. As already explained above, the active cathode is actually the liquid aluminium during electrolysis. In this case, however, the solid body forming a base plate is referred to as the cathode.
It is customary for the resulting liquid aluminium to be extracted discontinuously, once a day for example. This requires the crust that forms on the top of the electrolyte during the process, i.e. the mixture of cryolite and aluminium oxide, to be broken, in order to reach the aluminium. Between two such removals of aluminium, the level of the same rises in the cathode tank.
Generally, when aluminium is produced roughly 10 ¨ 20 % of the existing liquid aluminium is removed, while the remainder stays in the cathode tank. The aluminium level is roughly 15 - 50 cm on average. Due to the forces exerted on the aluminium through the electromagnetic interaction, bulges and wave formation are resulting in the molten aluminium. This means that in order to avoid a short-circuit the anodes must be spaced further away from the surface of the liquid aluminium than would be the case without the wave formation. For this reason, it would be desirable for the bulge and wave movement of the aluminium melt to be kept as low as possible on a continuous basis. Moreover, the discontinuous extraction of aluminium causes a significant disruption of the electrical and thermal equilibrium in the electrolytic cell.
One problem addressed by the invention is therefore to specify an electrolytic cell used to extract aluminium, in which the level of the aluminium melt can be kept constant and can be stabilised. A further problem addressed by the invention is to specify a fused-salt electrolysis process, in which high energy efficiency can be achieved.
This problem is solved according to the invention by an electrolytic cell with the features contained in claim 1 and also by a process according to claim 11.
Preferred embodiments are specified in the respective dependent claims.
07.03.2013 In accordance with embodiments of the invention an electrolytic cell used to extract aluminium from its oxide exhibits a cathode and a surrounding side wall, wherein the side wall is provided with a number of passages that open up outwardly into an overflow trough.
Within the meaning of the invention, the term "cathode" is interpreted quite generally. It may be, for example (although not exclusively), a so-called cathode bottom, which is made from a plurality of cathode blocks, so that the core aspects according to the invention are realised as a whole by this cathode bottom in the electrolytic cell according to the invention. However, the term cathode is also intended to refer to the partial structures forming such a cathode bottom, within the meaning of cathode blocks. All features that may contribute to the invention in connection with a "cathode" do so in the same way in connection with a "cathode block" or "cathode blocks", without this having to be expressly explained below.
When using an electrolytic cell according to the invention to extract aluminium by fused-salt electrolysis, it is possible for the resulting aluminium to be continuously removed, so that the aluminium level in the actual electrolytic cell can always be kept at a constant level. The passages advantageously reduce reflection of the flowing aluminium at the side walls of the electrolytic cell. The aforementioned wave formations can thereby be reduced, which is why the anode or anodes of the electrolytic cell can be moved close to the surface of the aluminium, without there being the risk of a short-circuit. However, this also means that the distance between the anode(s) and cathode can be reduced and the specific energy requirement for the fused-salt electrolysis process can thereby be reduced compared with the state of the art. Through the continuous removal of the aluminium formed, the operating performance of the cell is stabilised, as the conditions within the cell do not change, or barely change, over time.
It is advantageous in an embodiment of the electrolytic cell according to the 07.03.2013 r 5 invention for a collecting launder to be attached to the outer periphery of the overflow trough in such a manner that liquid (i.e. particularly liquid aluminium) passing over the upper edge of an outer border of the overflow trough flows into the collecting launder. This kind of embodiment makes it easier for the liquid aluminium produced during fused-salt electrolysis to be continuously removed.
In this embodiment, the aluminium accumulating above the cathode during the process passes via the passages formed in the surrounding side wall into the overflow trough. The level of liquid aluminium thereby produced exhibits the same or virtually the same height in the overflow trough and in the tank of the electrolytic cell. If further aluminium is now produced in the electrolytic cell during the performance of the fused-salt electrolysis, the level rises in the cathode tank and also in the overflow trough. If it thereby reaches the upper edge of the outer border of the overflow trough, any further rise of the level will cause aluminium to flow over the border into the collecting launder, from where it can be removed. This means that the aluminium level within the cathode tank never rises beyond a specific level, which is determined by the height of the upper edge of the outer border of the tank.
At least some of the passages in the surrounding side wall of the electrolytic cell, particularly all passages, may advantageously be formed at the same height above the cathode. This makes an even discharge of the liquid aluminium into the tank easy.
Moreover, it has proved to be particularly favourable for the cathode to be horizontal. In this way, the filling level of the resulting aluminium at each point within the tank is at least virtually the same depth during the performance of the aforementioned fused-salt electrolysis and uniform process conditions can therefore be maintained over the entire cathode surface.
In accordance with an embodiment of the invention the overflow trough exhibits outer walls, which are provided with a thermal insulation. This thermal 07.03.2013 insulation fulfils the function of preventing the molten aluminium from cooling too quickly. In order to be able to maintain the effect of keeping the aluminium level constant by means of an overflow structure, which can be achieved with the electrolytic cell according to the embodiments of the invention, it is necessary for the aluminium to remain in its liquid state until it has been removed from the overflow trough or from the collecting launder. However, this requires a sufficiently high temperature outside the cathode tank too. The insulation of the overflow; trough and possibly also of the collecting launder helps to minimise unnecessary heat losses from those components.
In a further advantageous embodiment of the electrolytic cell, the passages are formed equidistant to one another in the surrounding side wall. In this way, the discharge of liquid aluminium, i.e. of aluminium melt, is largely uniform and even, in which case the creation of turbulences and the formation of waves within the cathode tank are largely precluded during the discharge. For the same reason, it is favourable to limit the number of passages not to a too small number. A number of roughly 2 to 5 passages per m length of side wall have proved to be particularly suitable.
In relation to the size and shape of the passages, these may exhibit a diameter of between 3 and 15 cm, for example, if they are circular in cross-section, which is advantageous with regard to flow conditions. If a cross-sectional shape other than a circle is chosen, the design can correspond to the equivalent diameters with regard to the upper values. "Equivalent diameter" refers in this case to any cross-sectional dimension that produces a cross-sectional area corresponding to a circular area with this diameter. A rectangular cross-section may also be advantageous, in which case a width of the cross-section may be greater than its height.
In accordance with an embodiment of the invention, the surrounding outer wall of the cathode is disposed rotationally symmetrically around a central column.
In this case the outer wall may exhibit a circular or a regular polygonal form when viewed from above. In this context, "rotationally symmetrical" means any SGL CARBON SE
07.03.2013 form that can be brought into congruence with the original form when rotated around the centre at an angle of rotation of under 360 . Examples of such outer wall profiles may also be regular polygons. The rotational symmetry produces a uniform discharge of the aluminium melt over the entire tank area of the tank-shaped cathode.
The aforementioned central column may be tapered downwards radially towards the outside. This is particularly advantageous when it comes to filling the cathode tank, as will be discussed in greater detail below.
With regard to the versatility of use of the electrolytic cell, it is advantageous for the outer side wall of the overflow trough to be height-adjustable. As the height of the outer side wall, therefore the height of the upper edge of the outer border above the passages, determines the height of the aluminium level within the cathode tank, a height-adjustable outer side wall enables the aluminium level to be varied quickly and easily according to need. A mechanical or motorised adjusting device may be provided to adjust the height of the side wall.
A process for continuously extracting aluminium from its oxide by fused-salt electrolysis, in which the electrolytic cell according to the invention can be used, comprises the removal of the aluminium produced by fused-salt electrolysis from the collecting launder, which is fed from an overflow of an overflow trough, which is connected by passages to the inside of an electrolytic cell used during fused-salt electrolysis below the level of the aluminium produced in the cathode tank.
Since the aluminium is therefore discharged from the side of the electrolytic cell, it can flow into the overflow trough continuously and uniformly, which means that the level of liquid aluminium is always kept constant in the cathode tank. As already mentioned, movements in the liquid or melt can thereby be largely avoided, so that the surface of the molten aluminium in the cathode tank remains smooth and the anodes can therefore also be brought close to the level of the liquid aluminium, without there being any risk of a short-circuit between ,1 07.03.2013 the anodes and cathodes through the aluminium. The energy efficiency of the aluminium production process can therefore be significantly improved.
Moreover, the continuous discharge means that a more stable method of operation is guaranteed.
In order to ensure the smoothest possible removal of liquid aluminium, it is thereby advantageous for the fused-salt electrolysis to be carried out above a temperature of approx. 750 C, particularly between 930 und 1000 C. A lower temperature threshold of 750 C ensures that the aluminium melt is still sufficiently liquid outside the tank of the electrolytic cell to be able to flow over the edge of the overflow trough into the collecting launder and to be removed from there. Where there are suitable conditions, in which the heat loss in the outer parts of the overflow trough and collecting launder is kept low, it is prevented to fall below the aforementioned lower temperature limit. However, because this kind of process is advantageously conducted well above the aluminium melting point, for technical reasons, adequate flowability is generally ensured for the aluminium without further measures being required.
The invention will now be described in greater detail with reference to the attached drawing using a non-restrictive embodiment. In the drawing:
Fig. la shows a cross section of an electrolytic cell for the extraction of aluminium oxide according to the state of the art, Fig. lb shows the electrolytic cell from Fig. la in an external longitudinal view, Fig. lc shows a perspective view, partially in section, of an electrolytic cell for the extraction of aluminium from aluminium oxide according to the state of the art, Fig. 2a shows a cross-sectional view of a section of an electrolytic cell according to an embodiment of the invention, 07.03.2013 Fig. 2b shows a top view of the electrolytic cell from Fig. 2a; and Fig. 3 shows a configuration of anodes, which is adapted to the cathode form according to Fig. 2a and Fig. 2b, The same reference symbols are used in the figures to refer to the same or corresponding elements in the different representations.
With reference to Figure 2a, an electrolytic cell according to a first embodiment is shown in cross-section, which is suitable for use in the extraction of aluminium from aluminium oxide using the Hall-Heroult process already described. The electrolytic cell is made up of a cathode 1 and a surrounding side wall 1a, which is provided with passages 1aa. The side wall 1a along with the cathode 1 delimits the tank 1c, which gives the electrolytic cell its tank shape. There are several connections 1d at the lower end of the cathode 1, which are used to connect to pins 3, which are disposed vertically in the present example and are connected to a common current bar 3a.
A central column 1e is formed in the centre of the tank 1c, which exhibits a tip, as can be seen in Fig. 2a, i.e. runs downwards in an outward direction. This shape assists with the introduction of the mixture 6 of aluminium oxide and possibly cryolite and/or aluminium fluoride, in other words the liquid electrolytes, into the tank lc of the electrolytic cell. In this case, the outward tapering brings about a desired reduction in wave movements in the liquid aluminium when the electrolytic cell is filled during fused-salt electrolysis.
Different levels of the substances involved in the process are drawn into the figure: the lowest line shows the level of liquid aluminium 5 that accumulates close to the cathode 1. The mixture 6 is located above the aluminium 5 and is upwardly limited by a crust 6a of solidified melt 6, which forms during the course of the process.
The anodes 4 used as an opposite pole for the cathode 1 in the fused-salt SGL CARBON SE
07.03.2013 electrolysis process are contained in the cover 9. As can be seen in the figure, the anodes 4 are lowered so far into the tank lc of the electrolytic cell that from the upper end they come close to the level of the aluminium 5. This is possible because the electrolytic cell is an electrolytic cell according to an embodiment of the invention, which exhibits an overflow trough 10 adjacent to the surrounding side wall 1a, whose outer side wall 10a is limited at the top by the upper edge of an outer border 10b and at the bottom by a lower outer wall 10c.
A collecting launder 11 is attached to the outer side wall 10a or formed in one piece together with the collecting launder.
When performing the fused-salt electrolysis according to the known Hall-Heroult process, liquid aluminium 5 is produced at the cathode 1 from the liquid electrolyte, which settles close to the cathode 1. Since the cathode tank 1c is connected via the passages 1 aa in the side wall 1a of the electrolytic cell below a desired target level for the aluminium 5, the level in the overflow trough 10 also rises as more aluminium is produced. If the filling level shown in Figure 2a is reached, according to which the level of the aluminium 5 is at the height of the upper edge of the outer border 10b of the overflow trough 10, as the process continues aluminium 5 flows over the outer border 10b into the collecting launder 11, from where it can be removed using traditional means.
As a result of this design, the level of aluminium 5 both within the overflow trough 10 and in the tank 1c of the cathode 1 is limited to a desired target level, which is defined by the height of the upper edge of the outer border 10b of the overflow trough. So that the target level can be easily altered, it is favourable for the outer side wall 10a of the overflow trough 10 to be height-adjustable via the lower outer wall 10c. This may, for example, be achieved through an immersible wall construction (not shown). Furthermore, it is favourable in relation to the process management for heat losses from the molten aluminium 5 close to the overflow trough 10 and also the collecting launder 11 to be minimised as far as possible, in order to prevent the melt from starting to solidify before it has been removed from the run-off collector 11. This may be achieved, for example, by thermal insulation (not shown in the figures) of the outer walls , SGL CARBON SE
07.03.2013 10a, 10c of the overflow trough and possibly also of the collecting launder 11.
Structural measures aimed at keeping the surface of the aluminium 5 within the overflow trough 10 as small as possible also have the same effect. It is favourable, therefore, for the overflow trough 10 to be designed with a small width b, between roughly 50 mm and 100 mm, for example.
Now with reference to Figure 2b, a top view of the electrolytic cell in Figure 2a is shown. It can be seen that the side wall la of the electrolytic cell exhibits rotational symmetry here. The shape of the base area of the cathode 1 is that of a star with cropped jags. It should be noted that this shape is not obligatory and that a traditional rectangular tank lc or another tank shape, for example, is also possible for the electrolytic cell according to the invention.
The top view of Figure 2b furthermore shows the central column le, which exhibits the shape of a regular hexagon in this case. Dotted lines are used to identify the connections 1d (six of them in this case) for the pins 3 shown in Figure 2a designed as current supply devices, which run into the cathode 1 perpendicular to the image plane. In the embodiment shown the connections 1d represent a radial centre around which respective bulges in the side wall la run.
As likewise indicated by dotted lines, the tank 1c of the electrolytic cell may be divided into individual sections if or sectors, which can be regarded as partial cells of an electrolytic cell connected to one another. Because the dotted lines do not represent genuine barriers, but simply serve as virtual limits to clarify the position of the sections if or sectors, only a single section if was defined in its limits by these lines in the figure.
Beyond the side wall la of the electrolytic cell, the outer side wall 10a of the overflow trough 10 can be seen, which is continuous in the case shown and has an outer contour that matches the outer contour of the side wall 1a of the cathode 1. The passages 1aa and the collecting launder 11 are not shown in Figure 2b.
ri 07.03.2013 n 12 With reference to Figure 3, a configuration of anodes 4 is shown from above, which are designed as part of the section of an electrolytic cell represented in Figures 2a and 2b to act as the entire electrolytic cell.
In this case the base areas 4a of the anodes 4 exhibit the shape of elongated, inward-tapering hexagons (six of them here) in the top view, which are disposed in a star shape around a common centre Z. This means that the shape and number of anodes 4 corresponds to the shape and number of sections If or sectors of the cathode 1 in Figures 2a and 2b. However, it should be noted that the size of the sections If does not correspond to those of the associated anodes 4. Instead, the base area of the anodes 4, which is visible in the top view in Figure 3, is smaller than that of the associated section if, which means that the anodes 4 can be lowered into the tank 1c of the cathode 1 while the electrolytic cell is in operation.
With the cathode unit according to the invention and also the process according to the invention, the energy efficiency of an electrolytic cell for fused-salt electrolysis used to extract aluminium can be improved, due to the fact that the anodes and cathode can be moved closer together, as the continuous removal of the aluminium produced means that the filling level of the same in the cathode tank is low and/or a surface largely free from wave movements can be achieved. The height of the level can be kept at least largely at a target position within the cathode tank, so that in addition to a tracking of the anodes due to their consumption during the process, no additional tracking is required. A
high quality of the aluminium produced and also an optimised temperature control can thereby be achieved.
In relation to cathode and anode materials, any materials known to the person skilled in the art and suitable for the electrolysis of aluminium from its oxide may be used. Suitable materials are specified in DE 10261745, for example, the content of which, in this respect, is to be incorporated here by reference.
=
SGL CARBON SE
07.03.2013 Reference list 1 Cathode 1a Side wall 1aa Passage 1c (Cathode) tank 1d Connections 1e Central column If Section 2 Mounting 3 (Current-carrying) pin 3a Current bar 4 Anode 4a Base area Aluminium 6 Mixture (aluminium oxide, cryolite) 6a Crust of solidified melt 6 7 Negative pole, voltage source 8 Positive pole, voltage source 9 Cover Overflow trough 10a Outer side wall 10b Outer border 10c Lower outer wall 11 Collecting launder
The Hall-Heroult process is currently used for the industrial extraction of aluminium from its oxide. This is an electrolytic process in which aluminium oxide (A1203) is dissolved in molten cryolite (Na3 [AlF6]) and the resulting mixture acts as a liquid electrolyte in an electrolytic cell. In principal, the design of such an electrolytic cell used to carry out the Hall-Heroult process is depicted schematically in Figures la to lc, wherein Figure 1 a shows a cross-section through a traditional cell, while Figure lb shows an external side view of the cell. Fig. lc shows a perspective view of an electrolytic cell.
Reference symbol 1 denotes a cathode, which may, for example, be made from graphite, anthracite or a mixture thereof. Alternatively, coke-based graphitised cathodes may also be used. The cathode 1 is generally embedded in a mounting 2 made from steel and/or a fire-resistant material or the like. The cathode 1 may be made in one piece as well as may be made from individual cathode blocks. Reference symbol 20 denotes the side walls of the electrolytic cell, which form a tank along with the cathode. This tank may also be regarded as the internal lining of the mounting. The side walls may also be made in one piece as well as may be made from individual blocks.
Over the entire length of the cell, a number of current supply bars 3 are introduced into the cathode 1, although only a single current supply bar 3 can be seen in the cross-sectional view in Figure la. It can be seen in Fig. lc that two current supply bars, for example, may be provided for each cathode block.
The current supply bars are used to supply the cell with the current required for the electrolytic process. There is a plurality of prismatic anodes 4 opposite the cathode 1, while two anodes 4 are depicted in Figure la. Fig. 1 c shows a SGL CARBON SE
07.03.2013 detailed configuration of anodes in an electrolytic cell. During the performance of the process, the aluminium oxide dissolved in cryolite is reduced to aluminium wherein the aluminium cations move to the molten aluminium ¨
actually the cathode from an electrochemical point of view ¨ where they accept electrons by applying a voltage between cathode 1 and anodes 4. Due to the greater density, aluminium 5 gathers in the liquid phase beneath the molten mixture 6 of aluminium oxide and cryolite. The oxygen ions are reduced to oxygen at the anode, said oxygen reacting with the carbon of the anodes.
Reference symbols 7 and 8 are the schematic representations of the negative and positive poles, respectively, of a voltage source for providing the voltage required for the electrolytic process, the value of which lies between around 3.5 and 5 V, for example.
As can be seen in the side view in Figure 1 b, the mounting 2 and therefore the entire electrolytic cell traditionally has an elongated form, in which a plurality of current supply bars 3 are conducted vertically through the side walls of the mounting 2. The longitudinal expansion of cells currently in use is typically between around 8 and 15 m, while the width expansion is around 3 to 4 m. A
cathode, as is shown here in Figure la, is disclosed in EP 1845174, for example.
The high binding energy between aluminium and oxygen and also the heat and resistance losses cause a high energy requirement when producing aluminium by fused-salt electrolysis. The associated energy costs constitute the main part of the process costs. Reducing these costs is one of the major problems that need to be overcome in the field of fused-salt electrolysis. A major factor in relation to the energy efficiency of a fused-salt electrolytic cell is the distance required between the anode and cathode or, more accurately, the distance between the anode and the molten aluminium. The greater this distance has to be, the higher is the specific energy requirement of the electrolytic cell.
The distance required between the anode and cathode is primarily determined , 07.03.2013 3 , by the magnetic field induced by the extremely high current intensities of up to approx. 500 kA, by the electromagnetic interactions and by the thereby resulting wave movements and bulges of the liquid aluminium. As already explained above, the active cathode is actually the liquid aluminium during electrolysis. In this case, however, the solid body forming a base plate is referred to as the cathode.
It is customary for the resulting liquid aluminium to be extracted discontinuously, once a day for example. This requires the crust that forms on the top of the electrolyte during the process, i.e. the mixture of cryolite and aluminium oxide, to be broken, in order to reach the aluminium. Between two such removals of aluminium, the level of the same rises in the cathode tank.
Generally, when aluminium is produced roughly 10 ¨ 20 % of the existing liquid aluminium is removed, while the remainder stays in the cathode tank. The aluminium level is roughly 15 - 50 cm on average. Due to the forces exerted on the aluminium through the electromagnetic interaction, bulges and wave formation are resulting in the molten aluminium. This means that in order to avoid a short-circuit the anodes must be spaced further away from the surface of the liquid aluminium than would be the case without the wave formation. For this reason, it would be desirable for the bulge and wave movement of the aluminium melt to be kept as low as possible on a continuous basis. Moreover, the discontinuous extraction of aluminium causes a significant disruption of the electrical and thermal equilibrium in the electrolytic cell.
One problem addressed by the invention is therefore to specify an electrolytic cell used to extract aluminium, in which the level of the aluminium melt can be kept constant and can be stabilised. A further problem addressed by the invention is to specify a fused-salt electrolysis process, in which high energy efficiency can be achieved.
This problem is solved according to the invention by an electrolytic cell with the features contained in claim 1 and also by a process according to claim 11.
Preferred embodiments are specified in the respective dependent claims.
07.03.2013 In accordance with embodiments of the invention an electrolytic cell used to extract aluminium from its oxide exhibits a cathode and a surrounding side wall, wherein the side wall is provided with a number of passages that open up outwardly into an overflow trough.
Within the meaning of the invention, the term "cathode" is interpreted quite generally. It may be, for example (although not exclusively), a so-called cathode bottom, which is made from a plurality of cathode blocks, so that the core aspects according to the invention are realised as a whole by this cathode bottom in the electrolytic cell according to the invention. However, the term cathode is also intended to refer to the partial structures forming such a cathode bottom, within the meaning of cathode blocks. All features that may contribute to the invention in connection with a "cathode" do so in the same way in connection with a "cathode block" or "cathode blocks", without this having to be expressly explained below.
When using an electrolytic cell according to the invention to extract aluminium by fused-salt electrolysis, it is possible for the resulting aluminium to be continuously removed, so that the aluminium level in the actual electrolytic cell can always be kept at a constant level. The passages advantageously reduce reflection of the flowing aluminium at the side walls of the electrolytic cell. The aforementioned wave formations can thereby be reduced, which is why the anode or anodes of the electrolytic cell can be moved close to the surface of the aluminium, without there being the risk of a short-circuit. However, this also means that the distance between the anode(s) and cathode can be reduced and the specific energy requirement for the fused-salt electrolysis process can thereby be reduced compared with the state of the art. Through the continuous removal of the aluminium formed, the operating performance of the cell is stabilised, as the conditions within the cell do not change, or barely change, over time.
It is advantageous in an embodiment of the electrolytic cell according to the 07.03.2013 r 5 invention for a collecting launder to be attached to the outer periphery of the overflow trough in such a manner that liquid (i.e. particularly liquid aluminium) passing over the upper edge of an outer border of the overflow trough flows into the collecting launder. This kind of embodiment makes it easier for the liquid aluminium produced during fused-salt electrolysis to be continuously removed.
In this embodiment, the aluminium accumulating above the cathode during the process passes via the passages formed in the surrounding side wall into the overflow trough. The level of liquid aluminium thereby produced exhibits the same or virtually the same height in the overflow trough and in the tank of the electrolytic cell. If further aluminium is now produced in the electrolytic cell during the performance of the fused-salt electrolysis, the level rises in the cathode tank and also in the overflow trough. If it thereby reaches the upper edge of the outer border of the overflow trough, any further rise of the level will cause aluminium to flow over the border into the collecting launder, from where it can be removed. This means that the aluminium level within the cathode tank never rises beyond a specific level, which is determined by the height of the upper edge of the outer border of the tank.
At least some of the passages in the surrounding side wall of the electrolytic cell, particularly all passages, may advantageously be formed at the same height above the cathode. This makes an even discharge of the liquid aluminium into the tank easy.
Moreover, it has proved to be particularly favourable for the cathode to be horizontal. In this way, the filling level of the resulting aluminium at each point within the tank is at least virtually the same depth during the performance of the aforementioned fused-salt electrolysis and uniform process conditions can therefore be maintained over the entire cathode surface.
In accordance with an embodiment of the invention the overflow trough exhibits outer walls, which are provided with a thermal insulation. This thermal 07.03.2013 insulation fulfils the function of preventing the molten aluminium from cooling too quickly. In order to be able to maintain the effect of keeping the aluminium level constant by means of an overflow structure, which can be achieved with the electrolytic cell according to the embodiments of the invention, it is necessary for the aluminium to remain in its liquid state until it has been removed from the overflow trough or from the collecting launder. However, this requires a sufficiently high temperature outside the cathode tank too. The insulation of the overflow; trough and possibly also of the collecting launder helps to minimise unnecessary heat losses from those components.
In a further advantageous embodiment of the electrolytic cell, the passages are formed equidistant to one another in the surrounding side wall. In this way, the discharge of liquid aluminium, i.e. of aluminium melt, is largely uniform and even, in which case the creation of turbulences and the formation of waves within the cathode tank are largely precluded during the discharge. For the same reason, it is favourable to limit the number of passages not to a too small number. A number of roughly 2 to 5 passages per m length of side wall have proved to be particularly suitable.
In relation to the size and shape of the passages, these may exhibit a diameter of between 3 and 15 cm, for example, if they are circular in cross-section, which is advantageous with regard to flow conditions. If a cross-sectional shape other than a circle is chosen, the design can correspond to the equivalent diameters with regard to the upper values. "Equivalent diameter" refers in this case to any cross-sectional dimension that produces a cross-sectional area corresponding to a circular area with this diameter. A rectangular cross-section may also be advantageous, in which case a width of the cross-section may be greater than its height.
In accordance with an embodiment of the invention, the surrounding outer wall of the cathode is disposed rotationally symmetrically around a central column.
In this case the outer wall may exhibit a circular or a regular polygonal form when viewed from above. In this context, "rotationally symmetrical" means any SGL CARBON SE
07.03.2013 form that can be brought into congruence with the original form when rotated around the centre at an angle of rotation of under 360 . Examples of such outer wall profiles may also be regular polygons. The rotational symmetry produces a uniform discharge of the aluminium melt over the entire tank area of the tank-shaped cathode.
The aforementioned central column may be tapered downwards radially towards the outside. This is particularly advantageous when it comes to filling the cathode tank, as will be discussed in greater detail below.
With regard to the versatility of use of the electrolytic cell, it is advantageous for the outer side wall of the overflow trough to be height-adjustable. As the height of the outer side wall, therefore the height of the upper edge of the outer border above the passages, determines the height of the aluminium level within the cathode tank, a height-adjustable outer side wall enables the aluminium level to be varied quickly and easily according to need. A mechanical or motorised adjusting device may be provided to adjust the height of the side wall.
A process for continuously extracting aluminium from its oxide by fused-salt electrolysis, in which the electrolytic cell according to the invention can be used, comprises the removal of the aluminium produced by fused-salt electrolysis from the collecting launder, which is fed from an overflow of an overflow trough, which is connected by passages to the inside of an electrolytic cell used during fused-salt electrolysis below the level of the aluminium produced in the cathode tank.
Since the aluminium is therefore discharged from the side of the electrolytic cell, it can flow into the overflow trough continuously and uniformly, which means that the level of liquid aluminium is always kept constant in the cathode tank. As already mentioned, movements in the liquid or melt can thereby be largely avoided, so that the surface of the molten aluminium in the cathode tank remains smooth and the anodes can therefore also be brought close to the level of the liquid aluminium, without there being any risk of a short-circuit between ,1 07.03.2013 the anodes and cathodes through the aluminium. The energy efficiency of the aluminium production process can therefore be significantly improved.
Moreover, the continuous discharge means that a more stable method of operation is guaranteed.
In order to ensure the smoothest possible removal of liquid aluminium, it is thereby advantageous for the fused-salt electrolysis to be carried out above a temperature of approx. 750 C, particularly between 930 und 1000 C. A lower temperature threshold of 750 C ensures that the aluminium melt is still sufficiently liquid outside the tank of the electrolytic cell to be able to flow over the edge of the overflow trough into the collecting launder and to be removed from there. Where there are suitable conditions, in which the heat loss in the outer parts of the overflow trough and collecting launder is kept low, it is prevented to fall below the aforementioned lower temperature limit. However, because this kind of process is advantageously conducted well above the aluminium melting point, for technical reasons, adequate flowability is generally ensured for the aluminium without further measures being required.
The invention will now be described in greater detail with reference to the attached drawing using a non-restrictive embodiment. In the drawing:
Fig. la shows a cross section of an electrolytic cell for the extraction of aluminium oxide according to the state of the art, Fig. lb shows the electrolytic cell from Fig. la in an external longitudinal view, Fig. lc shows a perspective view, partially in section, of an electrolytic cell for the extraction of aluminium from aluminium oxide according to the state of the art, Fig. 2a shows a cross-sectional view of a section of an electrolytic cell according to an embodiment of the invention, 07.03.2013 Fig. 2b shows a top view of the electrolytic cell from Fig. 2a; and Fig. 3 shows a configuration of anodes, which is adapted to the cathode form according to Fig. 2a and Fig. 2b, The same reference symbols are used in the figures to refer to the same or corresponding elements in the different representations.
With reference to Figure 2a, an electrolytic cell according to a first embodiment is shown in cross-section, which is suitable for use in the extraction of aluminium from aluminium oxide using the Hall-Heroult process already described. The electrolytic cell is made up of a cathode 1 and a surrounding side wall 1a, which is provided with passages 1aa. The side wall 1a along with the cathode 1 delimits the tank 1c, which gives the electrolytic cell its tank shape. There are several connections 1d at the lower end of the cathode 1, which are used to connect to pins 3, which are disposed vertically in the present example and are connected to a common current bar 3a.
A central column 1e is formed in the centre of the tank 1c, which exhibits a tip, as can be seen in Fig. 2a, i.e. runs downwards in an outward direction. This shape assists with the introduction of the mixture 6 of aluminium oxide and possibly cryolite and/or aluminium fluoride, in other words the liquid electrolytes, into the tank lc of the electrolytic cell. In this case, the outward tapering brings about a desired reduction in wave movements in the liquid aluminium when the electrolytic cell is filled during fused-salt electrolysis.
Different levels of the substances involved in the process are drawn into the figure: the lowest line shows the level of liquid aluminium 5 that accumulates close to the cathode 1. The mixture 6 is located above the aluminium 5 and is upwardly limited by a crust 6a of solidified melt 6, which forms during the course of the process.
The anodes 4 used as an opposite pole for the cathode 1 in the fused-salt SGL CARBON SE
07.03.2013 electrolysis process are contained in the cover 9. As can be seen in the figure, the anodes 4 are lowered so far into the tank lc of the electrolytic cell that from the upper end they come close to the level of the aluminium 5. This is possible because the electrolytic cell is an electrolytic cell according to an embodiment of the invention, which exhibits an overflow trough 10 adjacent to the surrounding side wall 1a, whose outer side wall 10a is limited at the top by the upper edge of an outer border 10b and at the bottom by a lower outer wall 10c.
A collecting launder 11 is attached to the outer side wall 10a or formed in one piece together with the collecting launder.
When performing the fused-salt electrolysis according to the known Hall-Heroult process, liquid aluminium 5 is produced at the cathode 1 from the liquid electrolyte, which settles close to the cathode 1. Since the cathode tank 1c is connected via the passages 1 aa in the side wall 1a of the electrolytic cell below a desired target level for the aluminium 5, the level in the overflow trough 10 also rises as more aluminium is produced. If the filling level shown in Figure 2a is reached, according to which the level of the aluminium 5 is at the height of the upper edge of the outer border 10b of the overflow trough 10, as the process continues aluminium 5 flows over the outer border 10b into the collecting launder 11, from where it can be removed using traditional means.
As a result of this design, the level of aluminium 5 both within the overflow trough 10 and in the tank 1c of the cathode 1 is limited to a desired target level, which is defined by the height of the upper edge of the outer border 10b of the overflow trough. So that the target level can be easily altered, it is favourable for the outer side wall 10a of the overflow trough 10 to be height-adjustable via the lower outer wall 10c. This may, for example, be achieved through an immersible wall construction (not shown). Furthermore, it is favourable in relation to the process management for heat losses from the molten aluminium 5 close to the overflow trough 10 and also the collecting launder 11 to be minimised as far as possible, in order to prevent the melt from starting to solidify before it has been removed from the run-off collector 11. This may be achieved, for example, by thermal insulation (not shown in the figures) of the outer walls , SGL CARBON SE
07.03.2013 10a, 10c of the overflow trough and possibly also of the collecting launder 11.
Structural measures aimed at keeping the surface of the aluminium 5 within the overflow trough 10 as small as possible also have the same effect. It is favourable, therefore, for the overflow trough 10 to be designed with a small width b, between roughly 50 mm and 100 mm, for example.
Now with reference to Figure 2b, a top view of the electrolytic cell in Figure 2a is shown. It can be seen that the side wall la of the electrolytic cell exhibits rotational symmetry here. The shape of the base area of the cathode 1 is that of a star with cropped jags. It should be noted that this shape is not obligatory and that a traditional rectangular tank lc or another tank shape, for example, is also possible for the electrolytic cell according to the invention.
The top view of Figure 2b furthermore shows the central column le, which exhibits the shape of a regular hexagon in this case. Dotted lines are used to identify the connections 1d (six of them in this case) for the pins 3 shown in Figure 2a designed as current supply devices, which run into the cathode 1 perpendicular to the image plane. In the embodiment shown the connections 1d represent a radial centre around which respective bulges in the side wall la run.
As likewise indicated by dotted lines, the tank 1c of the electrolytic cell may be divided into individual sections if or sectors, which can be regarded as partial cells of an electrolytic cell connected to one another. Because the dotted lines do not represent genuine barriers, but simply serve as virtual limits to clarify the position of the sections if or sectors, only a single section if was defined in its limits by these lines in the figure.
Beyond the side wall la of the electrolytic cell, the outer side wall 10a of the overflow trough 10 can be seen, which is continuous in the case shown and has an outer contour that matches the outer contour of the side wall 1a of the cathode 1. The passages 1aa and the collecting launder 11 are not shown in Figure 2b.
ri 07.03.2013 n 12 With reference to Figure 3, a configuration of anodes 4 is shown from above, which are designed as part of the section of an electrolytic cell represented in Figures 2a and 2b to act as the entire electrolytic cell.
In this case the base areas 4a of the anodes 4 exhibit the shape of elongated, inward-tapering hexagons (six of them here) in the top view, which are disposed in a star shape around a common centre Z. This means that the shape and number of anodes 4 corresponds to the shape and number of sections If or sectors of the cathode 1 in Figures 2a and 2b. However, it should be noted that the size of the sections If does not correspond to those of the associated anodes 4. Instead, the base area of the anodes 4, which is visible in the top view in Figure 3, is smaller than that of the associated section if, which means that the anodes 4 can be lowered into the tank 1c of the cathode 1 while the electrolytic cell is in operation.
With the cathode unit according to the invention and also the process according to the invention, the energy efficiency of an electrolytic cell for fused-salt electrolysis used to extract aluminium can be improved, due to the fact that the anodes and cathode can be moved closer together, as the continuous removal of the aluminium produced means that the filling level of the same in the cathode tank is low and/or a surface largely free from wave movements can be achieved. The height of the level can be kept at least largely at a target position within the cathode tank, so that in addition to a tracking of the anodes due to their consumption during the process, no additional tracking is required. A
high quality of the aluminium produced and also an optimised temperature control can thereby be achieved.
In relation to cathode and anode materials, any materials known to the person skilled in the art and suitable for the electrolysis of aluminium from its oxide may be used. Suitable materials are specified in DE 10261745, for example, the content of which, in this respect, is to be incorporated here by reference.
=
SGL CARBON SE
07.03.2013 Reference list 1 Cathode 1a Side wall 1aa Passage 1c (Cathode) tank 1d Connections 1e Central column If Section 2 Mounting 3 (Current-carrying) pin 3a Current bar 4 Anode 4a Base area Aluminium 6 Mixture (aluminium oxide, cryolite) 6a Crust of solidified melt 6 7 Negative pole, voltage source 8 Positive pole, voltage source 9 Cover Overflow trough 10a Outer side wall 10b Outer border 10c Lower outer wall 11 Collecting launder
Claims (15)
1. An electrolytic cell used to extract aluminium from its oxide, exhibiting a cathode (1) and a surrounding side wall (1a), characterised in that the side wall (1a) is provided with a number of passages (1aa), that open up outwardly into an overflow trough (10).
2. The electrolytic cell according to claim 1, characterised in that a collecting launder (11) is attached to the outer periphery of the overflow trough (10) in such a manner that liquid aluminium passing over an outer border (10b) of the overflow trough (10) flows into the collecting launder (11).
3. The electrolytic cell according to claim 1 or 2, characterised in that at least some of the passages (1aa) in the surrounding side wall (1a) are formed at the same height above the cathode (1).
4. The electrolytic cell according to one or more of the preceding claims, characterised in that the cathode (1) is horizontal.
5. The electrolytic cell according to one or more of the preceding claims, characterised in that the overflow trough (10) exhibits outer walls (10a, 10c), which are provided with a thermal insulation.
6. The electrolytic cell according to one or more of the preceding claims characterised in that the passages (1aa) are formed equidistant to one another in the surrounding side wall (1a).
7. The electrolytic cell according to one or more of the preceding claims characterised in that the passages (1aa) each exhibit a diameter of between 3 and 15 cm.
8. The electrolytic cell according to one or more of the preceding claims characterised in that the surrounding side wall (1a) is disposed rotationally symmetrically around a central column (1e).
9. The electrolytic cell according to one or more of the preceding claims characterised in that the central column (1e) is tapered downwards radially towards the outside.
10. The electrolytic cell according to one or more of the preceding claims, characterised in that at least one outer wall (10a) of the overflow trough (10) is height-adjustable.
11. A process for continuously extracting aluminium from its oxide by fused-salt electrolysis, characterised in that the resulting aluminium is discharged from a collecting launder (11), which is fed from an overflow of an overflow trough (10), which is connected by passages (1aa) with the inside of an electrolytic cell used during fused-salt electrolysis below the level of the aluminium produced in the electrolytic cell.
12. The process according to claim 11, characterised in that the fused-salt electrolysis is carried out above a temperature of 750 °C, particularly between 930 and 1000 °C.
13. The process according to claim 11 or 12, characterised in that the electrolyte and/or aluminium oxide required for the fused-salt electrolysis is continuously supplied from a centre of the electrolytic cell.
14. The process according to one or more of the claims 11 to 13, characterised in that the centre is disposed in the central column (1e).
15. The process according to one or more of the claims 11 to 14, characterised in that it is carried out using an electrolytic cell according to one or more of the claims 1 to 10.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE201010041084 DE102010041084A1 (en) | 2010-09-20 | 2010-09-20 | Electrolysis cell for the production of aluminum |
| DE102010041084.5 | 2010-09-20 | ||
| PCT/EP2011/066317 WO2012038423A1 (en) | 2010-09-20 | 2011-09-20 | Electrolysis cell for extracting aluminium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2811357A1 true CA2811357A1 (en) | 2012-03-29 |
Family
ID=44651848
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2811357A Abandoned CA2811357A1 (en) | 2010-09-20 | 2011-09-20 | Electrolytic cell for extracting aluminium |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP2619350A1 (en) |
| JP (1) | JP2013540898A (en) |
| CN (1) | CN103180486A (en) |
| CA (1) | CA2811357A1 (en) |
| DE (1) | DE102010041084A1 (en) |
| RU (1) | RU2013118243A (en) |
| WO (1) | WO2012038423A1 (en) |
Family Cites Families (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE564404A (en) * | 1957-01-31 | |||
| GB1162153A (en) * | 1965-09-08 | 1969-08-20 | Conzinc Riotinto Ltd | Production of Aluminium and Aluminium Alloys |
| CH544578A (en) * | 1973-02-09 | 1973-11-30 | Alusuisse | Electrode block for an electrolysis cell with a current conducting bar in a groove in the electrode block |
| JPS5857517B2 (en) * | 1974-04-30 | 1983-12-20 | アルカン・アルミニウムヴエルケ・ゲゼルシヤフト・ミツト・ベシユレンクテル・ハフツング | Aluminum Den Cairo |
| NO764014L (en) * | 1975-12-31 | 1977-07-01 | Aluminum Co Of America | |
| CH643885A5 (en) * | 1980-05-14 | 1984-06-29 | Alusuisse | ELECTRODE ARRANGEMENT OF A MELTFLOW ELECTROLYSIS CELL FOR PRODUCING ALUMINUM. |
| JPS5741393A (en) * | 1980-08-27 | 1982-03-08 | Sumitomo Alum Smelt Co Ltd | Electrolytic furnace for production of aluminum |
| ZA824257B (en) * | 1981-06-25 | 1983-05-25 | Alcan Int Ltd | Electrolytic reduction cells |
| EP0103350B1 (en) * | 1982-06-18 | 1986-04-16 | Alcan International Limited | Aluminium electrolytic reduction cells |
| AU2824084A (en) * | 1984-02-03 | 1985-08-27 | Commonwealth Aluminium Corporation | Refractory hard metal containing plates for aluminium cell cathodes |
| DE69526264T2 (en) * | 1994-09-08 | 2002-10-24 | Moltech Invent S.A., Luxemburg/Luxembourg | Aluminum electrolytic cell with drainable cathode |
| DE10261745B3 (en) | 2002-12-30 | 2004-07-22 | Sgl Carbon Ag | Cathode system for electrolytic aluminum extraction |
| PL1845174T3 (en) | 2006-04-13 | 2011-10-31 | Sgl Carbon Se | Cathodes for aluminium electrolysis cell with non-planar slot design |
| CN201228286Y (en) * | 2007-11-23 | 2009-04-29 | 高德金 | Novel aluminum cell structure |
| CN101323958A (en) * | 2007-11-23 | 2008-12-17 | 高德金 | Novel aluminum cell structure |
| CN201390784Y (en) * | 2009-03-03 | 2010-01-27 | 沈阳铝镁设计研究院 | Cathode structure of aluminum electrolytic tank |
| CN201367468Y (en) * | 2009-03-05 | 2009-12-23 | 沈阳铝镁设计研究院 | Cathode structure of horizontal discharging aluminium electrolysis bath |
| CN201416037Y (en) * | 2009-06-16 | 2010-03-03 | 沈阳铝镁设计研究院 | Novel aluminum electrolytic cell |
-
2010
- 2010-09-20 DE DE201010041084 patent/DE102010041084A1/en not_active Withdrawn
-
2011
- 2011-09-20 RU RU2013118243/02A patent/RU2013118243A/en not_active Application Discontinuation
- 2011-09-20 EP EP11757661.1A patent/EP2619350A1/en not_active Withdrawn
- 2011-09-20 CA CA2811357A patent/CA2811357A1/en not_active Abandoned
- 2011-09-20 JP JP2013529631A patent/JP2013540898A/en active Pending
- 2011-09-20 CN CN2011800452658A patent/CN103180486A/en active Pending
- 2011-09-20 WO PCT/EP2011/066317 patent/WO2012038423A1/en not_active Ceased
Also Published As
| Publication number | Publication date |
|---|---|
| WO2012038423A1 (en) | 2012-03-29 |
| RU2013118243A (en) | 2014-10-27 |
| DE102010041084A1 (en) | 2012-03-22 |
| CN103180486A (en) | 2013-06-26 |
| JP2013540898A (en) | 2013-11-07 |
| EP2619350A1 (en) | 2013-07-31 |
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