EP1101726B1 - Lifting and load handling device for an aluminium production installation - Google Patents

Abstract

A unit for the lifting and handling of charges (7) at the heart of an installation for the production of aluminium by igneous electrolysis is claimed, the installation comprising at least one series of electrolysis cells in series and being provided with a rail track destined to allow the displacement of at least one overhead crane over the series of cells for the realisation of the different functions necessary for operating the installation. The lifting and handling unit makes up one of the overhead cranes, on which are at least two lifting and handling assemblies, each mounted on a chariot (11, 12, 13), able to be displaced in a direction perpendicular to the translation of the station (7). This lifting and handling unit (7) is characterised in that the chariots are able to move on the unit one above the other in order to allow them to cross each other.

Description

The present invention relates to the general field of operation management an aluminum production facility, and more specifically an installation implementing the now widely used technique of igneous electrolysis.

It relates more particularly to a lifting and handling unit, while particularly intended to be used during metal casting operations or alumina, and handling of the lifting beam of the anode frames as well as various auxiliary handling associated with the operation of the electrolysis tanks.

The closest state of the art is seen in EP-A-2553923.

In a known manner, the production of aluminum by igneous electrolysis implements the electrolysis of alumina in a molten cryolite bath according to the reaction:

This reaction uses a melt comprising a mixture of cryolite and alumina, the temperature of which is generally above 800 ° C. take in account the energies implemented and in order to minimize the losses inherent in the phases restart, the aluminum production facilities implementing this technology, generally operate continuously at the level of of aluminum, the number and dimensions of which are based on the one hand, the amperage available from the direct current feeding the tanks, and secondly, from the quantity of desired production.

In addition, facilities are frequently organized in such a way that they present two series of tanks mounted parallel to each other, installed within the same building or in separate buildings, but symmetrically with respect to a central aisle intended in particular to allow the handling of the ladle containing molten alumina intended to fill the electrolytic tanks, and other part intended for the handling of receiving pockets of molten aluminum obtained by electrolysis.

Also, at the level of each series of tanks, is implemented a trolley of casting for handling the ladle. This casting carriage is equipped with a particular guidance system for handling said pocket with a capacity of typical lifting between 20 and 40 tons depending on the amperage of the tanks.

In addition, the installations in question also have handling, intended inter alia to operate a beam lifting frames anodic, raised at both ends, so that usually two of these type of trolley are implemented, with a typical capacity of between 10 and 20 tons. This lifting anodic frames, said frames being intended to receive and maintain within tanks the carbon anodes, is necessary as and when the wear of the anodes in the process of electrolysis and, still for the purpose of the continuity of the process.

To date, these carriages are mounted on the same traveling crane, moving according to a perpendicular direction relative to the translation of a bridge of more capacity important, moving over the vats ..

The trolleys, respectively casting and handling are mounted on the same track, with the furthest position from the center aisle both trucks, then the casting trolley. In other words, the configuration of such a unit can not be considered, given the dissymmetry as well operated at this unit only for specific positioning of the pot series compared to the aisle at which the ladle flows. Thus, it is constituted depending on this orientation a "right" bridge and a "left" bridge. In fact, when one wishes to arrange two series of tanks symmetrically from each other with respect to the central aisle receiving as already said the ladle, so it is necessary to have at least two types of this unit, respectively right and left, respectively at the level of the tank of the right series and the tank of the series of left.

In fact, notwithstanding the existence of a ferry, that is, a device capable of to allow the displacement of a crane from a series of tanks to the series of tanks parallel, it can not be considered to operate a right bridge on a series left and vice versa.

One of the objectives of the present invention is to reduce the costs of production and operation of aluminum production facilities. To this end, it aims to allow use indifferently on one or the other of said series of vats Parallels of the ladle handling and lifting bridges anodic.

Another object of the present invention is to allow, by design said bridge, to reduce the congestion generated and thereby reduce the costs inherent in civil engineering.

Another object of the invention is also to lighten the structure of the bridges placed in in order to optimize their service life and consequently reduce the costs of manufacturing.

The invention therefore relates to a unit for lifting and handling loads within of an igneous electrolysis plant, said installation comprising at least one series of electrolytic cells in series and being provided with a track intended to allow the displacement of at least one traveling crane at above said series of tanks, and intended to allow the realization of different functions necessary for the implementation of said installation.

This lifting and handling unit, constituting one of said overhead cranes, and on which are likely to move in a direction perpendicular to the translation of the unit, at least two lifting and handling assemblies mounted each on a trolley, is characterized in that said trolleys are susceptible to translate on said unit one above the other to allow their crossing respective.

In other words, the invention proposes a lifting and handling unit allowing, by the possible crossing of the two carriages that it comprises, a indifferent use on one or the other series of tanks mounted symmetrically compared to the central aisle.

According to a first characteristic of the invention, the raceways of the two carts are coplanar.

More specifically, the installation comprises two series of electrolysis tanks symmetrical with respect to the central aisle allowing the handling of the ladle and, the characteristic unit of the invention is capable of moving from a series of tanks at the level of the symmetrical series by means of a transhipment bridge.

More specifically, one of the trolleys is intended for handling the casting ladle and the other is intended for auxiliary work and also for lifting anodic frames. The unit can also accommodate two trolleys for work auxiliaries and the lifting of the anode frames.

According to another characteristic of the invention, the trolley handling casting moves at the level of internal raceways and the at least one auxiliary carriages at level of external raceways.

In another configuration, the auxiliary trolley (s) moves to top of the ladle handling trolley.

According to another embodiment, said carriages move below the handling trolley of the ladle.

La figure 1 est une représentation schématique en perspective de parties d'une installation pour la production d'aluminium montrant notamment une série de cuves d'électrolyse.

La figure 2 est une représentation schématique en perspective de l'unité de levage et de manutention conforme à l'invention.

La figure 3 est une représentation schématique en perspective du chariot de coulée représenté sur la figure 2.

La figure 4 est une représentation schématique en perspective du chariot auxiliaire qui permet également la manutention de la poutre de relevage des cadres anodiques, représenté sur la figure 2.

La figure 5 est une représentation schématique en section transversale partielle de l'unité telle que représentée à la figure 2.

Les figures 6 et 7 sont des représentations schématiques respectivement vue de face et vue de dessus de la poche de coulée en coopération avec une cuve d'électrolyse, manutentionnée par le chariot de coulée.

Les figures 8 et 9 sont des vues respectivement de face et de dessus de la manutention de la poutre de levage du cadre anodique.

Les figures 10 et 11 sont des représentations schématiques en section de deux modes de réalisation conformes à l'invention.

The manner in which the invention can be realized and the advantages which result therefrom will emerge more clearly from the following exemplary embodiments, given by way of indication but without limitation, in support of the appended figures.

Figure 1 is a schematic perspective representation of parts of an installation for the production of aluminum including a series of electrolysis tanks.

Figure 2 is a schematic perspective view of the lifting unit and handling according to the invention.

FIG. 3 is a schematic perspective representation of the casting carriage shown in FIG.

FIG. 4 is a schematic representation in perspective of the auxiliary carriage which also allows the handling of the lifting beam of the anode frames, represented in FIG. 2.

FIG. 5 is a schematic representation in partial cross-section of the unit as represented in FIG. 2.

Figures 6 and 7 are schematic representations respectively front view and top view of the ladle in cooperation with an electrolytic tank, handled by the casting carriage.

Figures 8 and 9 are respectively front and top views of the handling of the lifting beam of the anode frame.

Figures 10 and 11 are diagrammatic representations in section of two embodiments according to the invention.

There is shown in Figure 1 a schematic view of a series of electrolysis tanks (1) for the production of aluminum according to the so-called method of igneous electrolysis.

These tanks are installed in an installation including two series of tanks parallel and symmetrical with respect to a central aisle (6), at the level of which are located on the one hand, an alumina supply device of said tanks, and on the other hand, the implementation of a system for capturing and treating fumes, in particular gases resulting from the reaction of electrolysis (in particular monoxide and dioxide carbon, oxygen, as well as fluorinated emanations).

These tanks are substantially identical to each other and each comprise an access cover (2) inside the tank, in particular at the molten electrolysis bath proper, thus freeing access to the carbon anodes (3).

The aforementioned fume collection and treatment system is fed from pipes (4) emanating from said tanks.

As can be seen in Figure 1, this series of tanks is overcome of a rolling path (5) on which one or more of cranes, such as for example the overhead traveling crane (7) constituting the handling and lifting according to the invention, and shown in more detail at the level of Figure 2.

This crane (7) moves on the raceway (5) by means of rollers (8), whose motorisation has not been represented so as not to unnecessarily FIGS.

It comprises two parallel raceways (9) and (10), extending perpendicular to the raceways (5), that is to say with respect to the direction of translation of said unit (7).

These two raceways (9) and (10) are intended to receive respectively a carriage (11) hereinafter referred to as a casting carriage, and one or two carriages (12) and (13) hereinafter referred to as auxiliary carriages or frame lifting carriages anodic.

These two carriages will be described in more detail later.

As can be seen from the observation of Figure 2, but also from FIGS. 6, 10 and 11, the carriages respectively of casting (11) and lifting of the frames anodic (12, 13) are likely to intersect, to the extent that, as represented in conjunction with FIGS. 2, 6 and 11, said carriages (12) and (13) are capable of can pass over the casting carriage (11) or, as shown in FIG. 10, are likely to pass below said casting carriage (11).

In doing so, the trolleys respectively casting (11) and lifting frames anodes (12, 13) can be crossed without hindrance, of course as long as the carriage superior does not have a suspended load.

It is conceivable in fact all the interest of this device, which allows to transfer the unit of lifting and handling (7) of a series of tanks to the series of parallel tanks, symmetrical to the first compared to the central aisle (6), and to make it at the level of this parallel series, by reversing the positioning of the respective carts by simple crossing.

As we have seen, such a configuration makes it possible to achieve, in addition to simplification of the aluminum production facility, also to a reduction of its costs of implementation and operation.

The casting carriage (11) has been described in more detail with reference to FIG. This one basically consists of a U-shaped chassis (15) resting on the road rolling (9) by means of rollers (14), and in particular by means of two sets of rollers parallel (14). The motorization system of these rollers has not been shown in order not to not overload the figures unnecessarily.

This casting carriage (11) comprises a lifting device represented briefly and in particular the motorization (16) appears in Figure 3.

This carriage is intended to take charge of the ladle (23) (FIGS. 6 and 7), allow it to perform a translation so as to allow the filling of the ladle through a pipe (24) which is immersed in the tank (1). The liquid metal is sucked by a vacuum system connected to the pocket, installed on the trolley, or coming directly from the building.

FIG. 4 also shows in greater detail the carriage auxiliary or lifting carriage of the anode frames (12, 13).

These carriages, since the unit advantageously comprises two, are constituted a chassis (17) resting on the tracks (10), parallel, coplanar and external to the tracks (9), by means of rollers (18) motorized by motors (19).

These auxiliary carriages (12, 13) are also provided with lifting means. We have the drums on which the hoisting ropes (20) are wound, the motor (21) and, in FIG. 5, the lifting hook (22) located at the end of the cables.

For auxiliary tasks, only one of these trolleys is implemented.

On the other hand, since it is a question of carrying out the lifting of anodic frames level of each of the tanks, the two carriages are implemented simultaneously, respectively at the two ends of the lifting beam (25) of the frame supporting the anodes (26), as partially shown in Figure 8.

The advantages provided by the invention appear very clearly.

By the possibility of standardizing the handling and lifting unit, the costs are substantially reduced, especially since the number of such units necessary for operation of the aluminum production facility is diminished. Indeed, he becomes possible to increase the operating time of this unit.

In addition, in the context of the embodiment of the invention, as shown in connection with Figures 2, 6 and 11, the space generated by the carriages auxiliaries is reduced, thus allowing new installations to reduce dimensions of buildings housing these facilities, and thus the cost of civil engineering corresponding.

Claims (6)

1. A load lifting and handling unit (7) within an electrolytic aluminium production plant, the said plant comprising at least one series of electrolysis pots (1) in series and provided with a runway (5) designed to allow at least one overhead crane to travel over the said series of pots in order to carry out the various functions needed for operating the said plant, the said lifting and handling unit, constituting one of the said overhead cranes along which at least two lifting and handling assemblies each mounted on a crab (11, 12, 13) can move in a direction perpendicular to the displacement of the unit (7), characterized:

   in that one of the said lifting and handling assemblies consists of a pouring crab (11) intended to ensure filling of the pouring ladle (23) at the pots (1) and collection of the molten aluminium at the said pots;

   in that the other of the said lifting and handling assemblies consists of two auxiliary crabs (12, 13), intended for auxiliary work and for raising the anode frames at each of the said pots; and

   in that the pouring crab (11) and the two auxiliary crabs (12, 13) are able to move along the said unit, one over another and thus allow them to cross one another.
2. Lifting and handling unit according to Claim 1, characterized in that the runways (9, 10) for the crabs (11, 12, 13) are coplanar.
3. Lifting and handling unit according to either of Claims 1 and 2, characterized in that the pouring crab (11) travels along the inner runways (9) and the auxiliary crabs (12, 13) along the outer runways (10), the pouring crab being able to travel beneath the auxiliary crabs.
4. Lifting and handling unit according to either of Claims 1 and 2, characterized in that the pouring crab (11) travels along the inner runways (9) and the auxiliary crabs (12, 13) along the outer runways (10), the auxiliary crabs being able to travel beneath the crab (11) for handling the pouring ladle.
5. Electrolytic aluminium production plant comprising two series of electrolysis pots (1) that are symmetrical with respect to a central aisle (6) intended to allow handling of a pouring ladle (23) containing liquid aluminium produced by the said electrolysis pots, each of the series of pots being surmounted by a runway (5) intended to allow at least one overhead crane to travel over the said pots in order to carry out the various functions needed to operate the plant, characterized in that it includes a handling and lifting unit (7) according to one of Claims 1 to 4.
6. Electrolytic aluminium production plant according to Claim 5, characterized in that it furthermore includes at least one transfer crane intended to transfer, especially from the lifting and handling unit, one series of pots to the parallel series.

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