WO2013038352A1

WO2013038352A1 - A system consisting of an anode hanger means and an enhanced geometry anode

Info

Publication number: WO2013038352A1
Application number: PCT/IB2012/054750
Authority: WO
Inventors: Aldo Iván LABRA VARGAS
Original assignee: Labra Vargas Aldo Ivan
Priority date: 2011-09-16
Filing date: 2012-09-12
Publication date: 2013-03-21
Also published as: US20140262761A1; CN104040031A; DE112012003846T5; MX2014003239A; CL2011002307A1; JP2014530295A; PE20141387A1; KR20140090153A

Abstract

The present invention relates to a system consisting of an anode hanger means (10) and an enhanced geometry anode (22) which makes possible to reuse said anode hanger means (10) minimizing the production of scrap, allowing an enhancement of the process between the smelting and the electrorefining wherein said hanger means (10) is formed by a reusable central bar (11) to be located on the upper edge of the enhanced geometry anode (22) wherein said reusable central bar (11) has on its ends reusable ears (12) having engagement means (13) which take the enhanced geometry anode (22) on its upper corners and wherein in the upper corners of said enhanced geometry anode (22) emerge two small upper projections (15). The small upper projections (15) are fitted with said engagement means (13) to secure the hanger means (10) to the enhanced geometry anode (22). Alternatively, the hanger means (10) comprises a reusable independent central bar (16) wherein on the ends of said reusable independent central bar (16), are fitted two reusable independent ears (17) which have fastening means (18) formed by a lower notch (23) on which the small upper projection (15) of the enhanced geometry anode (22) is housed.

Description

A SYSTEM CONSISTING OF AN ANODE HANGER MEANS AND AN

ENHANCED GEOMETRY ANODE TECHNICAL FIELD OF THE INVENTION

The present invention relates to a system comprising reusable ears for copper anodes used in the electrorefining process, which replaces the need of having these same anodes formed by its own ears. These ears currently only serve for the electrical contact function and work as a current anode supporter, and, therefore, when finishing the electro- winning process on the cathodes, this material is left intact and must be re-smelted again to form a new anode. This invention makes possible to use an anode without ears which allows to minimize the scrap production together with its consequent associated costs. BACKGROUND OF THE INVENTION

The high-purity copper production process involves several stages starting with the reception and sampling of copper concentrates. It is important to perform a sampling of them as well as classify them according to the copper, iron, sulfur, silica concentrations and impurities such as mainly arsenic, antimony and zinc.

Following the classification process, the concentrate enters into the drying stage where the humidity is reduced from 8% to 0.2%, then the dried concentrated enters into the fusion process, whose objective is to achieve a change of state which allows the concentrate to pass from a solid state to a liquid state so as the copper can be separated from the other elements comprising the concentrate.

The copper concentrate fusion is a product of the instantaneous auto-ignition thereof, which takes place at high temperatures (greater to 1200 °C). In this process the concentrate passes from the solid state to a liquid state, the elements comprising the ores present in the concentrate are separated according to their weight, remaining the lighter ones on the upper part of what has been smelted (molten metal), which is called slag, mainly high iron and silica phases, while the copper associated to sulfur which is heavier, is concentrated on the lower part of the reactor, which is called Babbitt metal or bearing metal. Thus, it is possible to separate both parts by taking them out from the reactor by means of tapping passages located at different levels.

Fusion reactors and furnaces must be constantly loaded and permanently tapped, the high-copper material is carried in liquid form through pots or channels to the conversion process where a high copper phase called blister copper is produced (98.5 Cu). This product is subsequently carried in liquid form through pots or channels to a refining process where are mainly removed impurities such as dissolved sulfur, dissolved oxygen and impurities such as arsenic, antimony, bismuth, lead among others, such that finally results the obtaining of the product called anode copper with an average purity of 99.5 % of copper.

The anode copper is molded and solidified with a rectangular geometry of an anode plate (1) having ears (2) as showed in figure 1. The most used way to cast the anode copper is by means of a casting wheel which comprises a determined quantity of copper molds wherein the copper is poured at a temperature lower or equal to 1200°C, once the copper is poured into the casting wheel, the latter starts to spin and the smelted copper begins to cool in a first stage at ambient temperature until the upper part of the copper is solid, subsequently the copper passes by a cooling stage which comprises upper water cooling and lower water cooling. During this stage the copper decreases its temperature until reaching a complete solid state to be carried to the electrolytic refining plant in order to produce a high-purity cathode having copper contents higher or equal to 99.9 % Cu.

The anode copper is formed on a mold (7) which comprises a central rectangular-shaped cavity (8) to receive the liquid copper which forms the anode plate (1). On the upper part of said mold (7) and towards the corners of the central cavity (8) are located two cavities (9) to receive the liquid copper which comprises the ears (2) as can be seen in figures 6 and 7.

In the refineries, the anode (1) is introduced into an electrolytic cell (3), which has a cathode (4) that can be permanent or of mother sheet according to the technology to be used having its respective hanging bar (5). The electrolytic cell (3) is filled with an acid solution and current is applied to the contacts (6) in order to produce the electrowinning of the copper from the anode (1) towards the cathode (4) according to what is shown in figures 2 to 5. In this process the anode (1) only remains submerged up to the continuous zone of the ears (2) and due to this the upper part of the anode (1) does not participate in the electrolysis process as shown in greater detail in figure 3, thus using the ears (2) only to transport the same and for electrical contact.

When finishing the electrolytic cycle, this part of the anode remains intact and becomes an important part of the rest of the anode, together with the material that was not dissolved, called scrap. This material must be smelted again to form a new anode (1) and continuing with the complete cycle; this product is formed in all the existing refineries and the reprocessing cost is high wherein said product is made by means of different technologies existing in the market. The present invention proposes a new geometrical shape of the anode (1) which leads to separate the ears (2) of the anode body, by keeping a rectangular configuration or other shape of dimensions required by the electrorefining technology to be used, subsequently and downstream of the molding process must be incorporated the fastening system, which has already been dimensioned and standardized from the factory, according to the geometrical dimensions used by the existing technologies of electrorefining. The fastening system can be comprised by materials resistant to the acid solution used in the electro-erosion and having conductive elements that will allow to transmit the electric current to the modified anode such that the electrical contact can be the suitable one for the electrolysis process.

There have been several attempts in the state of the art to generate bars with ears for hanging cathodes as well as anodes during different processes within the obtaining of non-ferrous metals. Thus, for example, document EP 0284128 published on September 28, 1988 discloses a suspension bar for anode or a cathode sheet in the electrolytic refining of metals wherein the core of the suspension bar consists of a material which exhibits a high resistance to bending and a high mechanical resistance, and being surrounded by a sheath of a material with good electrical conducting properties. This material with good electrical conduction properties, such as copper, near at least one of the ends of the suspension bar and preferably near both ends, over a length of at least 3 cm and at most 5 cm, the sheath being continuous to the end of the core. In addition, this document discloses a method for the manufacture of a suspension bar in which a sheath of copper is drawn over a core of steel, starting from copper tube. Copper and steel cores are introduced into the copper tube, subsequently the sheath is drawn with further cores being added, to a total length which essentially corresponds to the change in length of the copper tube occurring as a result of the drawing and, finally, the rod produced is sawn up into the desired rod lengths at the points where the copper cores are located. Towards the center, the bar has two hooks to suspend an anode or cathode as the case may be.

Document ES 8303548 (Prengaman et al.) discloses a method of manufacture of a lead anode for the electrolytic extraction of metals. The lead anode is used in the electrolytic extraction of metals and comprises a sheet of lead anode material provided with one or more recesses on the surface of a lead-tin alloy coated copper bus bar in the slot of which is placed a sheet of lead anode material of one solder that joins the mentioned sheet to the bus bar and of deposits of lead alloy which join the existing joints between the mentioned sheet and the cited bus bar. The solder comprises a lead-tin-silver alloy to be applied in the electrowinning of copper, nickel and zinc.

Document CA 1095841 (Huppi) published on February 17, 1981 discloses an electrode hanger of unitary construction for an electrostatic precipitator having means on the upper end thereof for engaging with a current carrying support means and means on the lower end thereof for receiving an electrode thereon.

Document WO 2000/39366 (Prengaman) published on July 6, 2000 discloses a method of manufacturing electrowinning anode comprising adjusting a sheet of lead alloy in a slot in a bus bar; b) holding the bus bar on the sheet; c) electrowining a lead coating on a bus bar; the pin and joint to form a metallurgical bond around the bus bar, pin and joint between the sheet and the bus bar.

None of the above-mentioned documents discloses a system proposing a new geometrical shape for the anode having independent fastening means which makes possible to use said anode without ears, minimizing the production of scrap, thus allowing an enhancement of the process between the smelting and electrorefining.

SUMMARY OF THE INVENTION

The present invention relates to a reusable ear system for copper anodes allowing to hang these electrodes in order to carry them between the smelting process and the electrorefining which avoids smelting their own ears on these same anodes, thus generating a change of geometry that allow to enhance the process and thereby reducing the scrap.

Currently the anode copper molded by means of molding wheels has a great variability with respect to the geometrical dimensions, the aforementioned is mainly produced by a poor leveling of the molds or due to other factors of the molding process and this leads to the existence of a percentage of rejected anodes which do not comply with the allowed dimensions in the cell with the subsequent reprocessing of the defective anodes, thereby having an effect on the costs, this phenomenon becomes more critical when using technologies working with high current densities.

The system of the proposed invention starts with the modification of the mold of the previous art, which currently manufactures a standard anode (1) having ears (2) of the same molded material. This geometry of the mold must be modified by a mold geometry producing an anode without ears. The system of the present invention further incorporates a set of external ears to the original piece which have been manufactured according to a pre-established and standardized design according to the electrorefining or electrowinning technology to be used, containing conductive elements which allow to transmit the electric current to the modified anode such that the electrical contact is the suitable one for the electrorefining process and must be able to incorporate an electronic system by means of which through a software relevant information of the electrowinning process is received.

This modification of the anode can lead to a modification in the way of removing the anode from the wheel by means of robotized, automated or semi-automated system with a gripper systems or any other, to remove the anode from the wheel and place it on the water cooling pit.

The integrated anodes will be placed in the water cooling pit or in a subsequent stage before entering into the electrolytic cells. These integrated anodes must have a fitting system which guarantees the handling of the anode copper thereby allowing an excellent electrical contact within the cell and can be reusable, thus allowing the effective release of the rest of the anode which was not able to dissolve in the electrolysis stage.

The system of the invention comprises an anode with a special geometrical shape and a set of reusable pieces which are independently generated and incorporated as a system in subsequent stages into the molding process of the anode copper. The essence of the invention lays in the system of assembly which allows the operation handling of the anode copper allowing an efficient current conduction and incorporating technological elements which generate relevant information of the process. The system of this invention is reusable in the process.

The normal operating regime of the system allows to automate stages without the need of manual intervention, improving the security and productivity of the process from the previous art. Once the system of the invention is assembled this is handled in the same way as done by the current anode copper. Due to the aforementioned, a second object of this invention is providing a monitoring system which allows to measure the material flow within the discharge channel and in the evacuation zone.

BRIEF DESCRIPTION OF THE FIGURES

The accompanying figures are included to provide a better understanding of the invention. They are part of this description and also illustrate part of the previous art and some of the preferred embodiments in order to explain the principles of this invention.

Figure 1 shows a perspective view of an anode according to the previous art.

Figure 2 shows a perspective view, from the previous art, of an electrolytic cell with the anode and cathode inserted therein.

Figure 3 shows a perspective view, according to the previous art, of an electrolytic cell with the anode and cathode risen above the acid solution (electrolyte).

Figure 4 and 5 shows a perspective view, according to the previous art, of an electrolytic cell with the anodes and cathodes submerged in the acid solution (electrolyte).

Figure 6 shows a frontal elevation of a casting mold to form an anode according to the previous art.

Figure 7 shows a perspective view of a casting mold to form an anode according to the previous art.

Figure 8 shows a perspective view of a first embodiment of ears for fastening the anodes of the present invention.

Figure 9 shows a perspective view of a first embodiment of ears installed in an anode of the present invention. Figure 10 shows a front perspective view of a first embodiment of the set of ears and anode of the present invention.

Figure 11 shows an end perspective view of a first embodiment of the set of ears and anode of the present invention.

Figure 12 shows a perspective view of a cell for the electrorefining of copper with the set of ears and anode of the present invention.

Figure 13 shows a perspective view of a casting mold to form an anode according to the present invention.

Figure 14 shows a front elevation view of a casting mold to form an anode according to the present invention.

Figure 15 shows a perspective view of an anode according to the present invention.

Figure 16 shows a front elevation view of an anode according to the present invention.

Figure 17 shows a perspective view of a second embodiment of the set of ears and anode of the present invention.

Figure 18 shows a front elevation view of a second embodiment of the set of ears and anode of the present invention.

Figure 19 shows a front elevation view of a second embodiment of the set of ears and anode of the present invention wherein the ears are illustrated as stripped out from the anode. Figure 20 shows a front elevation view of a second embodiment of the set of ears and anode of the present invention wherein the ears are illustrated being mounted to the anode.

Figure 21 shows a front elevation view of a second embodiment of the set of ears and anode of the present invention wherein the ears are illustrated as mounted on the anode.

Figure 22 shows a cross section view of a second embodiment of the set of ears and anode of the present invention wherein the ears are illustrated as mounted on the anode.

Figure 23 shows a cross section view of a second embodiment of the set of ears and anode according to the present invention wherein the cavities for inserting sensors and circuits for the monitoring of variables generated from the process are illustrated.

DESCRIPTION OF THE INVENTION

The present invention consists of a set of elements of pieces which are assembled between each other forming an anode (1), the rectangular-shaped anode body is molded by a molding system by means of liquid metal coming from a furnace or reactor, the ears or ear system are manufactured in an unrelated place according to the pre- established design and material such that they establish a perfect electrical contact in the electrolytic cell, the ears or fastening system It has a design such that they can contain inside themselves an electronic system which allows to transmit electrical signals and of the electrolytic process. These elements are assembled to the anode body in a place past the molding system, once the rectangular anode body is at a suitable temperature for the assembly. The anode system can be installed in any system for molding copper or other metal.

The system is comprised by a rectangular-shaped body anode formed of a material preferably copper or other metal wherein said body is molded and solidified in a casting wheel system or other mechanism, this molded body and of dimensions according to specific requirements is carried by a robotized, automated machine or other carrying mechanism and cooled for its subsequent assembly. The anode with a modified geometry is further comprised by a fastening and handling means which can be joined between each other or separately. This fastening means serves for handling the anode and to make contact between the rectangular body and the electrolytic cell. The fastening means is manufactured of a material equal or different to the rectangular body, which can vary according to the design of the electrolytic cell technology to be used, these are strong enough such that they can support the weight of the rectangular body without being deformed and allowing a perfect verticality of the anode with a modified geometry in the electrolytic cell. In addition, this fastening means must be manufactured of a material inert to the solution in the electrolytic cell such that these are not dissolved in the electrolyte and can cause a detachment and fall of the rectangular body or of the fastening means itself within the interior of the cell.

The fastening means can have in its manufacturing design a section inside which is possible to incorporate an electronic element, by means of which it is possible to access to the relevant information of the process such as: weight loss of the anode system, short circuits and variables of the typical electrical type of the electrorefining or electrowinning process and variables of productive nature which make possible to observe the process as a whole. This information will be captured by means of a computing system especially developed for this process.

As can be seen in figures 8 to 12, the system of the present invention is comprised by an anode hanger means (10) and a anode of enhanced geometry (22).

In a first embodiment, the hanger means (10) comprises a reusable central bar

(11) to be located on the upper edge of the enhanced geometry anode (22). On the ends of the reusable central bar (11) emerge reusable ears (12) having engagement means (13) which take the enhanced geometry anode (22) on its upper corners.

The enhanced geometry anode (22) is formed in the mold (7) as shown in figures 13 and 14. In this case, the central rectangular- shaped cavity (8) receives the liquid copper forming the enhanced geometry anode plate (22). On the upper part of said mold (7) and towards the corners of the central cavity (8) are located two small recesses (14) to receive the liquid copper forming two small upper projections (15) which replace the ears (2) of the previous art.

These small upper projections (15) are used by the engagement means (13) to fasten the hanger means (10) to the enhanced geometry anode (22).

In a second embodiment of the present invention, the hanger means (10) comprises a reusable independent central bar (16). On the ends of this reusable independent central bar (16), are fitted two reusable independent ears (17) which have fastening means (18) formed by a lower notch (23) on which is housed the small upper projection (15) of the enhanced geometry anode (22).

The reusable independent ears (17) have on the opposite side to the fastening means (18), an overhanging short bar (19) with a male rim (21). This male rim (21) is fitted with a female slot (20) located on the reusable independent central bar (16). This allows to generate a fastening mechanism between said reusable independent central bar

(16) and said reusable independent ears (17) thus achieving a system which can be easily dismountable and mountable to be compacted during its transport.

In figures 19 to 22 is shown the assembly of this second embodiment of the present invention. The reusable independent central bar (16) is located on the upper edge of the enhanced geometry anode (22). In turn, two reusable independent ears (17) are displaced from the ends with the overhanging short bars (19) co-linear to the reusable independent central bar (16) until the male rim (21) of the reusable independent ears (17) are fitted with the female slot (20) of the reusable independent central bar (16). When this displacement takes place, the lower notches (23) of the fastening means (18) are also fitted with the small upper projections (15) of the enhanced geometry anode (22), thus generating the closure of the system and securing the anode to the hanger means (10). The female slot (20) and the male rim (21) form a tongue and groove joint member that makes possible the joint between the reusable independent central bar (16) and the reusable independent ears

(17) .

The hanger means (10) of the present invention also has cavities for the mounting of sensors and electrical circuits which allow to measure and control different parameters of the process. The sensors and circuits comprise communication means which emits signals that are received by a computing unit receiving means, which through a software processes the received data and transform them into relevant information of the process such as: weight loss of the anode system, short circuits and variables of the typical electrical type of the electrorefining or electrowinning process and variables of productive nature which make possible to observe the process as a whole. This information will be captured by means of a computing system especially developed for this process.

In figure 23 it is possible to observe that the hanger means (10) has in at least one of its reusable independent ears (17) first cavities (24) for installing sensors, circuits and communication means. On the center of the reusable independent central bar (16) there is also a second cavity (25) for the installation of sensors, electronic circuits and communication means. In both cases, the communication means deliver the obtained data from the sensors and electronic circuits to a computer which processes said data and delivers relevant information for the monitoring and control of the process.

Claims

1. - A system consisting of an anode hanger means (10) and an enhanced geometry anode (22) which makes possible to reuse said anode hanger means (10) minimizing the production of scrap, thus allowing an enhancement of the process between the smelting and the electrorefining characterized in that said hanger means (10) is formed by a reusable central bar (11) to be located on the upper edge of the enhanced geometry anode (22) wherein said reusable central bar (11) has on its ends reusable ears (12) having engagement means (13) which take the enhanced geometry anode (22) on its upper corners and wherein in the upper corners of said enhanced geometry anode (22) emerge two small upper projections (15).

2. - The system according to claim 1 characterized in that said small upper projections (15) are fitted with said engagement means (13) to secure the hanger means (10) to the enhanced geometry anode (22).

3. - The system according to claim 1 or 2 characterized in that said enhanced geometry anode (22) comprises a mold (7) having a central rectangular-shaped cavity (8) which receives the liquid copper to form the enhanced geometry anode plate (22) wherein towards the corners of the central cavity (8) are located two small recesses (14) to receive the liquid copper forming said small upper projections (15).

4. - The system according to any of the preceding claims characterized in that said hanger means (10) comprises a reusable independent central bar (16) wherein on the ends of said reusable independent central bar (16), are fitted two reusable independent ears (17) which have fastening means (18) formed by a lower notch (23) on which the small upper projection (15) of the enhanced geometry anode is housed.

5. - The system according to claim 4 characterized in that said reusable independent central bar (16) has a female slot (20).

6. - The system according to claim 5 characterized in that said reusable independent ears (17) have on the opposite side to the fastening means (18), an overhanging short bar (19) with a male rim (21).

7. - The system according to claims 4 and 5 characterized in that said female slot (20) and said male rim (21) form a tongue and groove joint means which allows the joint between said reusable independent central bar (16) and said reusable independent ears (17).

8. - The system according to any of claims 4 to 7 characterized in that the reusable independent central bar (16) is located on the upper edge of the enhanced geometry anode (22) wherein the two reusable independent ears (17) are displaced from the ends with the overhanging short bars (19) co-lineal to the reusable independent central bar (16) until the male rim (21) of the reusable independent ears (17) is fitted with the female slot (20) of the reusable independent central bar (16).

9. - The system according to claim 8 characterized in that said lower notches (23) of the fastening means (18) are also fitted with the small upper projections (15) of the enhanced geometry anode (22) thus generating the closure of the system and securing the anode to the hanger means (10).

10. - The system according to any of the preceding claims characterized in that said hanger means (10) has in at least one of its reusable independent ears (17) first cavities (24) for installing sensors, electronic circuits and communication means.

11.- The system according to any of the preceding claims characterized in that said reusable independent central bar (16) has on its center a second cavity (25) for installing sensors, electronic circuits and communication means.