JPH033750B2 - - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD This invention relates generally to anodes, and more particularly to special anode shapes and methods of manufacturing the same. [Background Art] Simply stated, copper electrorefining is an electrochemical process in which copper is leached from an impure anode and plated onto a pure copper cathode. The electrolyte in which these electrodes are immersed is generally an acidified copper sulfate solution. Currently, anodes are manufactured by pouring impure molten copper into molds. By convention, the mold is stationary or mounted in a rotating casting wheel. In each case, the general shape of the anode is illustrated in FIG. In particular, the typical profile of the lug is illustrated in FIG. An anode with such a protrusion profile does not sit vertically in the electrolytic cell, causing a short circuit between the anode and the cathode. In order to prevent this, the protrusion is bent by manually banging it inside the electrolytic cell, or a wedge is inserted under the protrusion. Some companies also use special processing machines to process the anode protrusion. All of this post-work is expensive. Other companies also cast full-size projectors (Figure 3). In such cases, a special filler metal must be placed in the mold cavity of the protrusion in order to mold out the anode. This is a labor-intensive operation and requires that such an anode (due to its thick ledge) occupy a large amount of space within the electrolytic cell. As a result, the production per electrolytic cell decreases. A solution to this problem is presented in the paper Continuous Casting of Anodes with Integral Projections (AIME, Chicago, February 1981) by JM Donpass, M. Gobert, and K. Hens, who developed a continuous casting method for anodes. is proposed. The profile of the anode protrusion is shown in FIG. Such an anode has a thin ledge, sits vertically in the electrolytic cell, and requires no other machining. However, this method requires special and complex machining and therefore has very high investment costs. SUMMARY OF THE INVENTION The present invention is based on the discovery that copper anodes that sit vertically in an electrolytic cell can be cast directly on a conventional anode casting wheel without the need for any other machining after casting. The ledge area of the mold is shaped so that the point of suspension of the anode is vertically above the center of gravity of the anode. To facilitate molding of the anode and to facilitate electrical contact between the anode and the conductive rod, a graphite suspension or other lubricant is sprayed into the lobed area of the mold during casting. Preferred Embodiments of the Invention Referring to FIG. 1, a conventional anode 10 is illustrated. This anode 10 has a main body portion 12 and a projecting portion 14 . The anode 10 is suspended by a ledge 14 into an electrorefining tank (not shown). A cross section of the projecting portion 14 is shown in FIG. This ledge 14 consists of an upper surface 16 sloping toward the front 18 of the anode 10, a rear surface 20 and a front 22, and a lower surface 24 sloping upward toward the anode front 18. As previously mentioned, the general shape of the anode 10 shown in FIGS. 1 and 2 does not allow the anode 10 to be placed vertically within the electrorefining vessel (see FIG. 9). Therefore,
The projecting portion 14 must be bent unnecessarily. This is exhausting. It's just a half-hearted measure.
An alternative to such a construction is a full size cast ledge 26 (FIG. 3). This is anode 10
Using an unnecessary amount of extra copper in the essentially non-reactive neck of the Furthermore, special fillers must be used in the mold to demold the anode from the mold. JM Donpass and others developed a continuous casting method,
In this case, the anode 10 has a thin bulge 28 and is vertical in the electrolytic cell. See Figure 4. FIG. 5 shows a partial cross-sectional view of the ledge 30 of the present invention. Note that the upper part of the anode 32 is thin. That is, the main body 36 is tapered toward the protruding portion 30 at the neck portion 56 . The anode 32 has an upper surface 34 that slopes downwardly toward the front surface 36 of the anode, and a front surface 38 and a rear surface 4.
0, and a lower surface 42. The lower surface 42 includes a downwardly sloped surface 44, a vertical step 46, and an upwardly sloped surface 48, with angle A being an opposite angle compared to FIG. The vertical step 46 ideally has a center of gravity 6
It coincides with plane F (vertical plane) passing through 0. When the anode 32 is inserted into the refining tank, the tip 62 formed by the intersection of the downwardly inclined surface 42 and the step 46
acts as the anode suspension edge and the anode is suspended vertically when the center of gravity 60 is aligned with the vertical plane below. FIG. 6 is a perspective view of the anode 32. Dimension G is approx.
It is 1.5 inches (3.8cm). It has been confirmed that the anode 32 with the protrusion 30 sits vertically in the refining tank and does not require any additional work. An anode 32 with a bulge 30 of this type can be cast on a conventional casting wheel, the bulge area of the mold being periodically coated with a light graphite spray during casting. Graphite has two functions. The first is to lubricate the projecting area of the mold to facilitate demolding of the anode.
The second function is that graphite acts as a reducing agent and an excellent conductor, preventing the formation of copper oxides and improving the electrical contact between the anode and the copper bar on which it rests in the smelting tank. In addition to graphite spray, it also controls mold warpage. A method for controlling mold warpage consists in using a double cavity mold as described in Canadian patent application no. FIG. 7 depicts a mold 50 that complements the desired ledge 30 structure. FIG. 8 is a detailed view of the ledge mold hole 52. For a “standard” 36 inch x 36 inch (0.914 m x 0.914 m) anode 32, the reverse angle A is approximately 5°, the dimension D is approximately 1 inch (2.54 cm), and the dimension E is approximately 1/8 inch (3.2mm). Dimension E is a function of the verticality of the anode (described below). A double cavity mold 50 (i.e., a double-sided mold) with a ledge hole 52 for creating the ledge 30 as shown in FIG. 5 is placed on a standard casting wheel. The anode 32 is systematically cast and a graphite spray is applied to the ledge hole 52 of the mold 50. Graphite lubricants are suspensions of graphite in water or other liquids, with or without dispersants or other agents of similar properties. The anode 32 can be easily molded out of the mold 50 by a push-up pin inserted through the aperture 54. This easy demolding of the anode 32 was quite surprising since it was thought that the opposite angle lobes could not be easily demolded due to their zeometry. A number of experimental heats were made to confirm the efficiency of the anode and its manufacturing method. The results are shown below. During a certain period of time, four groups of anodes (each group
(containing 38 anodes) were collected and measured for "verticality". The verticality of the normal anode 10 shown in FIG. 9 is expressed by the distance B between the anode and a true vertical line C when suspended in a refining tank. point 58
is the center of gravity of the anode. The closer this value B is to 0, the
The anode is nearly vertical. In some cases, if the anode swings to the side opposite to that shown in FIG. 6, the verticality of the anode becomes negative. Returning to FIG. 8, the dimension E can be changed depending on the magnitude and sign of this verticality. This dimension is also a function of anode bow. The greater the degree of warpage, the smaller the dimension E must be.

[Table] An anode 32 provided with a protrusion 30 as shown in FIGS. 5 and 6 by wheel casting has better performance than an ordinary anode 10 suspended in an electrolytic cell. It became clear. The anode, which is suspended vertically above the electrolyzer, can be cast on a conventional casting wheel with graphite for lubrication of the mold ledges. The anode of the present invention sits more vertically in the electrolytic cell than a conventional anode. As a result, manpower is significantly saved in the electrolytic cell and current efficiency is increased. Such improvements are achieved with minimal investment.
In fact, the payback time is approximately
It is estimated to be 100 times shorter. The present invention is not limited to the above description, but can be modified and implemented as desired within the scope of the spirit thereof.

[Brief explanation of drawings]

1 is a side view of a prior art anode, FIG. 2 is a partial sectional view taken along line 2-2 of FIG. 1, FIG. 3 is a partial sectional view of another prior art anode, and FIG. 4 is a partial sectional view of another prior art anode. 5 is a partial sectional view of an anode according to the present invention; FIG. 6 is a perspective view of an anode of the present invention; FIG. 7 is a perspective view of an anode mold; FIG. is a partially enlarged view of the mold in Figure 7, and Figure 9 is a partial enlarged view of the mold in Figure 1.
FIG. 3 is a side view of the anode shown in FIG. 10... Anode, 12... Main body, 14, 30...
Projection part, 32...Anode, 34...Protrusion part upper surface, 36...Main body front surface, 42...Protrusion bottom surface,
44...Downward inclined part of the lower surface 42, 46...Step part, 48...Upward inclined part, 50...Mold, 52
... Projection mold hole, 56 ... Main body tapered part, 60 ...
...Anode center of gravity, 62...Tip.

Claims (1)

[Scope of Claims] 1. includes a main body and an inverted angular ledge aligned with the main body, the main body has a front face and a back face, the main body has a tapered shape toward the ledge, and the inverted angular ledge is aligned with the main body; The projecting part allows the anode to be vertically suspended in the electrolytic cell, and the inverted projecting part includes an upper surface and a lower surface, the upper surface is inclined downward toward the front, and the lower surface has a plurality of parts. These parts are oriented so that the anode is vertically suspended in the electrolytic cell, and the lower surface of the inverted angled protrusion has a first part that is inclined downward toward the front of the main body, and a second part that is slanted downward toward the front of the main body. An anode including a second part extending upward from the first part, and a third part inclined upward from the second part toward the front of the main body. 2. An anode according to claim 1 containing copper. 3. An anode according to claim 1, wherein the opposite angle is about 5°. 4a the profile of the shaped ledge includes an upper surface and a lower surface, the upper surface slopes downwardly toward the front of the anode, and the lower surface is divided into a plurality of sections;
using an inverted angle mold containing ledge mold holes whose lower surface portions are oriented to suspend the anode vertically into the electrolytic cell; b. positioning the mold on a casting wheel; c. spraying a lubricant into the ledge mold cavity; d. casting the molten material into the mold; e. rotating the casting wheel; f. solidifying the molten material; g. the projecting part mold hole has a first part inclined downward with a lower part of the projecting part facing the front of the main body, and a second part extending upward from the first part; A method for casting an anode having a shape that includes a second part and a third part that slopes upward toward the front of the main body. 5. A method according to claim 4, wherein the molten substance comprises copper.