KR20180121397A - Electrode structure - Google Patents

Abstract

The present invention alleviates influence of temperature rise of an electrode structure itself. Accordingly, deterioration of the electrode structure is suppressed, and further, the electrode structure having a long electrode life is provided. A gap (C1) is formed between an electrode plate (2) and a feeder (3) other than a connection unit (4) so that an electrolytic solution can communicate therewith. The electrode plate (2) is cooled on both the front and back surfaces by passing the electrolyte solution through the gap (C1) so that the connection unit (4) can be cooled.

Description

[0001] ELECTRODE STRUCTURE [0002]

The present invention relates to an electrode structure.

Conventionally, in high-speed electrolytic plating or electrolysis such as high-speed zinc plating, by using an electrode structure formed by segmenting an electrode plate and fixing it to a plurality of support plates (feeders), even when an accident such as contact occurs, . The segment of the electrode plate is connected to the power supply via a connection portion. However, when a large current of, for example, a current density of 100 A / dm ^{2 to} 300 A / dm ² is caused to flow during electrolysis, a relatively large current flows in such a connection portion. In this case, if the electrical resistance of the connection portion is high, the amount of heat generated becomes excessive, which may cause deterioration of the electrode plate and hence the electrode structure.

For example, Patent Document 1 discloses a technique of arranging a lead plate between connecting portions between an electrode plate and a feeder. By arranging the lead plates therebetween, the contact between the electrode plate and the feeder becomes more tight, thereby preventing an increase in electrical resistance and suppressing heat generation.

Patent Document 1: JP-A-7-331495

However, Patent Document 1 is very effective when used in a dry state. However, when it is immersed in a liquid such as a sulfuric acid solution, it generates insulative sulphate lead or contributes to electrolysis though it is partial due to electric current, There was a problem that was consumed.

Therefore, in the present invention, it is an object of the present invention to provide an electrode structure which suppresses the deterioration of the electrode structure by alleviating the influence of the temperature rise of the electrode structure itself, and which has a longer electrode life.

In order to achieve the above object, according to the present invention, a gap is formed between an electrode plate and a feeder other than a connecting portion so that an electrolytic solution can pass therethrough, and the gap is filled with an electrolytic solution to cool the electrode plate on both the front and back surfaces In addition, the connections were also allowed to cool.

That is, the electrode structure disclosed herein includes an electrode plate made of titanium or a titanium alloy as a base material and a feeder for supporting the electrode plate, wherein the electrode plate and the feeder are tightly fixed to each other via a connecting portion A gap is formed between the electrode plate and the feeder so that the electrolyte solution can pass between the electrode plate and the feeder except for the connection portion when the electrode plate is immersed in the electrolyte, And the gap with the feeder is not less than 1 mm and not more than 20 mm.

For example, in the high-speed zinc plating line, the inventors of the present invention found that when the temperature of the electrolytic solution, that is, the electrolytic temperature rises above 60 ° C, the electrode life of the electrode plate is lowered, Lt; RTI ID = 0.0 > half. ≪ / RTI > The temperature rise of the electrode structure during electrolysis can be caused mainly by overvoltages caused by electrode reactions on the electrode surfaces of the electrode plates, heat generated due to the electrode plates, feedstock, and electrical resistance of these connecting portions. In the high-speed zinc plating line, the temperature of the electrolytic solution is usually kept at about 60 캜. However, since the amount of heat generated by the electrode structure is increased, the temperature of the electrode structure itself becomes higher than about 60 캜 of the electrolytic solution and the deterioration of the electrode structure is promoted have.

According to the above configuration, a gap is formed so as to allow the electrolytic solution to pass through between the electrode plates and the feeding members other than the connecting portion. Therefore, when the electrode structure is immersed in the electrolytic solution, Electrolyte flow occurs in the entire interspace. Then, the electrode plate itself is cooled on both the front and back surfaces by the electrolytic solution, so that the cooling area of the electrode plate can be increased. Further, the flow of the electrolytic solution is generated in the space between the electrode plate and the power supply, so that the flow of the electrolytic solution also occurs around the connection portion, and the connection portion with a high calorific value is also cooled. In addition, cooling of the feedstock can be promoted. Therefore, it is possible to prevent the electrode plate from overheating, thereby lowering the temperature of the electrode plate to a temperature near the same level as that of the electrolytic solution, and consequently to prolong the electrode life of the electrode structure.

The size of the gap is adjusted by the length of the connecting portion. However, as the length of the connecting portion becomes longer, the electrical resistance of the connecting portion increases and the amount of heat generated increases. By setting the size of the gap within the above-mentioned range, it is possible to suppress the rise of the electrical resistance of the connection portion and to secure the amount of electrolytic solution flowing between the electrode plates and the power supply members while suppressing the heat generation amount.

In a preferred embodiment, the electrode plate is composed of a plurality of segment electrode plates divided into a plurality of segments, and a gap of not less than 1 mm and not more than 3 mm is formed between the adjacent segment electrode plates.

According to this configuration, a gap is also formed between the adjacent segment electrode plates, so that the flow of the electrolyte also occurs between the segment electrode plates. Therefore, the cooling of the electrode plate and the connecting portion is promoted, and the electrode plate can be prevented from overheating, and the electrode life can be effectively extended.

In a preferred embodiment, the electrode plate is composed of a plurality of segment electrode plates divided into a plurality of segments, the connecting portion includes a convex portion formed on at least one of the segment electrode plate and the feed electrode, And a mounting member for mounting and fixing the plate and the feeder.

According to this configuration, maintenance of the electrode plate, such as replacement of the electrode plate, can be improved by dividing the electrode plate into a plurality of electrode plates. Further, by making the connecting portion a convex upper portion, the electrolytic solution flowing into the space between the electrode plate and the feeding members flows around the connecting portion, so that the connecting portion can be effectively cooled.

The mounting member is preferably a bolt. Thereby, the electrode plate and the feeder can be reliably tightly fixed.

Further, when the electrode plate is energized with a rated current through the feeder, the current density of the connection portion is preferably 0.3 A / mm 2 or more and 1.0 A / mm 2 or less. Thereby, it is possible to prevent the amount of heat generated at the connection portion due to the energization from becoming excessive while securing the amount of current required for electrolysis.

In a preferred embodiment, the shape of the cross section perpendicular to the energizing direction of the connecting portion is such that the flow of the electrolytic solution passing through the gap when the electrode plate is immersed in the electrolytic solution in the state where the electrode plate is fixed to the feed electrode is made laminar Shape. Thereby, turbulence is not generated in the flow of the electrolytic solution around the connection portion, so that the flow of the electrolytic solution around the connection portion is promoted, and a high cooling effect can be obtained.

It is preferable that a contact surface of the electrode plate and the feeder in the connection portion is covered with a platinum group metal. With this configuration, the electrical resistance of the contact surface can be lowered, and the amount of heat generated at the connection portion can be reduced.

Further, in a preferred aspect, the electrode plate and the power supply member in the connection portion are bonded to each other via a washer. According to this configuration, the strength of the connecting portion can be increased by providing a metal washer having a corrosion resistance and being disposed between the contact surfaces of the electrode plate and the powder feeder.

It is preferable that the washer is made of tantalum whose surface is coated with platinum. According to this configuration, it is possible to suppress heat generation at the contact surfaces of the electrode plate and the washer, the contact surfaces of the feeder and the washer.

These electrode structures can be suitably used as anodes for electrolytic plating.

As described above, according to the present invention, since a gap is formed so as to allow the electrolyte solution to pass through between the electrode plates and the feeding members other than the connecting portion, when the electrode structure is dipped in the electrolyte solution, , The electrolyte flows in the space between the electrode plate and the feed electrode. Then, the electrode plate itself is cooled on both the front and back surfaces by the electrolytic solution, so that the cooling area of the electrode plate can be increased. Further, the flow of the electrolytic solution is generated in the space between the electrode plate and the power supply, so that the flow of the electrolytic solution also occurs around the connection portion, and the connection portion with a high calorific value is also cooled. In addition, cooling of the feedstock can be promoted. Therefore, it is possible to prevent the electrode plate from overheating, thereby lowering the temperature of the electrode plate to a temperature near the same level as that of the electrolytic solution, and consequently to prolong the electrode life of the electrode structure.

1 is a plan view of an electrode structure according to the first embodiment.
2 is a vertical cross-sectional view taken along the line II-II of the electrode structure of FIG.
Fig. 3 is a diagram of the electrode structure of Fig. 1 viewed from the electrode back surface side of the segment electrode plate, and schematically shows an electrolyte flow around the connection portion. Fig.
Fig. 4 is a vertical cross-sectional view showing a connecting portion of an example segment electrode plate and a feeder in the electrode structure according to the second embodiment. Fig.
Fig. 5 is a view corresponding to Fig. 4 of an example of the electrode structure according to the second embodiment.
Fig. 6 is a view corresponding to Fig. 4 of the electrode structure according to the third embodiment.
7 is a plan view of the electrode structure used in the electrode surface temperature measurement test 2. Fig.
8 is a longitudinal sectional view taken along line VIII-VIII of the electrode structure of FIG.
Fig. 9 is a plan view of the electrode structure used in the electrode surface temperature measurement test 3. Fig.
10 is a longitudinal cross-sectional view of the X-X line of the electrode structure of Fig.
11 is a graph showing the relationship between the distance between the electrode plate and the feeding electrode of the electrode surface temperature measurement test 3 and the electrode surface temperature.
12 is a graph showing the relationship between the electrolysis temperature and the electrode life.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses thereof.

(First Embodiment)

<Electrode Structure and Manufacturing Method Thereof>

1 and 2, the electrode structure 1 according to the first embodiment includes an electrode plate 2 and a feeder 3 for supporting the electrode plate 2.

The electrode structure 1 is used as a cathode for high-speed electrolytic plating such as zinc, chromium, and tin. The electrode structure 1 is not limited to high-speed electrolytic plating, and can be used as other electrolytic electrodes, as a cathode for foil or the like, a surface oxidation treatment or the like.

The electrode plate 2 has a role of promoting the electrolytic reaction at the electrode surface 21A by being fed. The electrode plate (2) is constituted by a plurality of segment electrode plates (21) divided into a plurality. The electrode plate 2 may be divided or divided, but it is preferable that the electrode plate 2 is divided and divided into a plurality of segment electrode plates so as to be detachably attached to the power supply 3, Is preferable. The surface area of the electrode surface of the electrode plate 2 and the size, shape, thickness, longevity and the like of the segment electrode plate 21 can be appropriately changed depending on the use of the electrode structure 1 and are not particularly limited .

The segment electrode plate 21 has a base material and an electrode surface 21A formed by forming an electrode coating made of an electrode material on one surface of the base material. The substrate is a titanium or titanium alloy agent excellent in corrosion resistance even when a strongly acidic liquid is used as an electrolytic solution. The titanium may be, for example, JIS 1 or 2, and the titanium alloy may be Ti / Pd alloy, for example. The electrode material is not particularly limited but is, for example, Ir / Ta oxide, Pt, Pt / Ir alloy, Pt / Ir oxide, etc. from the viewpoint of promoting the reaction on the electrode surface 21A. The method of forming the electrode coating is not particularly limited, but is formed by vapor deposition, plating, pyrolysis, CVD or the like.

The feeder 3 supports the electrode plate 2 and supplies electricity to the electrode plate 2 through a feed cable connected to the back surface of the feeder 3. The power supply 3 may be made of a commonly used material, but at least the portion of the surface of the power supply 3 that comes into contact with the electrolytic solution is made of metal which is corrosion resistant to the electrolytic solution. The metal is, for example, titanium, a titanium alloy, zirconium, niobium or tantalum, preferably titanium or a titanium alloy. As the titanium or titanium alloy, specifically, the same material as the base material of the electrode plate 2 can be used. The size, shape, thickness, longevity, and the like of the feeder 3 can be appropriately changed depending on the intended use of the electrode structure 1, and are not particularly limited. For example, It is also possible to constitute the electrode structure 1 by arranging a plurality of the power supply units 3 having the plurality of segment electrode plates 21. In this case,

The segment electrode plate 21 and the feeder 3 are tightly fixed to each other via the connecting portion 4. [

The connecting portion 4 has a role to energize the electricity supplied to the power supply 3 to the segment electrode plate 21. The electrode plate boss portion 41A formed in the segment electrode plate 21 And a bolt 43 (mounting member) for mounting and fixing the segment electrode plate 21 and the feeding member 3 on the electrode plate boss portion 41A.

A bolt insertion through hole 42 for inserting the bolt 43 is formed near the center of the electrode plate boss portion 41A. The segment electrode plate 21 and the feeder 3 are brought into contact with each other by the electrode plate side contact surface 44 (contact surface) and the feeder side contact surface 45 (contact surface).

The electrode plate side contact surface 44 and the power supply side contact surface 45 (hereinafter sometimes referred to as "contact surfaces 44, 45") are machined by a polishing machine from the viewpoint of reducing electric resistance. It is preferable that at least one of the contact surfaces 44 and 45, more preferably both of them, are covered with a platinum group metal such as Pt or Pd. With this structure, the electrical resistances of the contact surfaces 44 and 45 can be reduced. Therefore, it is possible to reduce the amount of heat generated by the connecting portion 4 during energization. The electrode back surface 21B of the segment electrode plate 21 and the feed surface 3A of the feeder 3 may be machined or not machined.

A bolt hole 46 is formed at a position corresponding to the bolt insertion through hole 42 when the vicinity of the center of the power supply side contact surface 45, that is, the contact surfaces 44 and 45 are in contact with each other.

The segment electrode plate 21 is fixed to the bolt hole 46 of the feeder 3 by a bolt 43 inserted into the bolt insertion through hole 42. At this time, the plurality of segment electrode plates 21 are mounted on the power supply 3 so that the height of the electrode surface 21A described above is the same with respect to the power supply 3.

The method of attaching and fixing the segment electrode plate 21 to the power feeder 3 is not particularly limited and any method can be employed. From the viewpoint, bolt fastening is preferable. In the present specification, the term &quot; bolt fastening &quot; as used herein means, in addition to a configuration in which the bolt 43 is fixed to the feeder 3 on the electrode surface 21A side as shown in Fig. 2, And is fixed to the segment electrode plate 21. [ It is also possible to arrange stud bolts in the segment electrode plate 21 or the feed electrode 3 and fix them to the feeder 3 or the segment electrode plate 21, for example. These are generically referred to as &quot; bolt fastening &quot;.

The material of the bolt 43 is a corrosion-resistant metal with respect to the electrolytic solution, preferably a titanium or titanium alloy. As the titanium or titanium alloy, specifically, the same material as the base material of the electrode plate 2 can be used.

From the viewpoint of suppressing the amount of heat generated by the connecting portion 4 and promoting cooling by the electrolytic solution, it is preferable that the connecting portion 4 be thinner, but thicker from the viewpoint of current density. The diameter of the connecting portion 4 varies depending on the value of the applied electric current. For example, when the electric current is passed through the rated current (current density of about 100 A / dm ² to about 500 A / dm ² ) The current density of the connection portion 4 is preferably 0.3 A / mm 2 or more and 1.0 A / mm 2 or less, more preferably 0.55 A / mm 2 or more and 0.75 A / mm 2 or less, from the viewpoint of suppressing the heat generation amount of the connection portion 4 while securing the power supply amount. / Mm &lt; 2 &gt;.

Here, the electrode structure 1 according to the present embodiment is characterized in that a gap C1 is formed between the segment electrode plate 21 and the feeder 3. The presence of the gap C1 allows the electrolytic solution to pass between the segment electrode plate 21 and the feeder 3 other than the connecting portion 4 when the electrode structure 1 is immersed in the electrolytic solution, The flow of the electrolytic solution occurs between the segment electrode plate 21 and the power supply 3 and around the connection portion 4 as indicated by arrows in Fig. In this case, since the segment electrode plate 21 itself is cooled on both the front and back surfaces by the electrolytic solution, the cooling area of the segment electrode plate 21 can be increased. Further, the connection portion 4 having a large heat generation amount is also cooled by the flow of the electrolytic solution around the connection portion 4. Therefore, it is possible to prevent the segment electrode plate 21 from overheating, and the temperature of the electrode surface of the segment electrode plate 21, that is, the electrode plate 2 as a whole, It is possible to extend the electrode life of the electrode. However, for example, in the conventional electrode structure as described in Patent Document 1, a gap is not formed between the electrode plate and the feeding member other than the connecting portion between the electrode plate and the feeding member, from the viewpoint of preventing the penetration of the electrolyte solution, A very small gap of about 0.5 mm or less is usually formed. A very small gap is intended to prevent the electrode from being damaged due to short-circuiting such as impurities in the electrolytic solution interposed between the electrode plate and the electrolytic solution. However, with such a small gap, the electrolytic solution may cause a flow The amount of the penetration does not occur.

The gap C1 between the segment electrode plate 21 and the feeder 3 is preferably 1 mm or more and 20 mm or less. If the clearance C1 is less than 1 mm, the electrolytic solution hardly flows smoothly and the cooling effect may be reduced. If the clearance C1 exceeds 20 mm, the electrical resistance of the connection portion 4 becomes large due to the increase in the length of the connection portion 4, and the amount of heat generated by the connection portion 4 may rise excessively. From the viewpoint of compactness of an apparatus such as an electrolytic cell in which the electrode structure 1 is provided, the size of the gap C1 is more preferably 3 mm or more and 10 mm or less.

The adjacent segment electrode plates 21 may be disposed so as to be in contact with each other. However, as shown in Figs. 1 and 2, for example, the gap C1 between the segment electrode plate 21 and the feed electrode 3 , And a gap C2 may be formed between the adjacent segment electrode plates 21 as well. By forming the interval C2, a flow of the electrolytic solution also occurs between the segment electrode plates 21 as shown by the arrow in Fig. Therefore, the cooling of the electrode plate 2 and the connecting portion 4 is promoted, thereby preventing the electrode plate 2 from overheating and effectively extending the life of the electrode. The size of the interval C2 is preferably 1 mm or more and 3 mm or less. As shown in Fig. 1, the interval C2 is divided into a first interval C21 and a second interval C22. At least one of the first interval C21 and the second interval C22 is preferably formed in the interval C2. For example, when the electrode structure 1 is used as an anode for plating a metal plate material, the distance C2 between 1 mm and 3 mm is formed in the direction perpendicular to the flow direction of the metal plate material to be plated, And the cooling effect is enlarged. In addition, a gap in the direction parallel to the flow direction of the metal plate material to be plated may be formed, but there is a possibility that the plating thickness of the plated steel sheet may become uneven, so that it is preferable to form the interval C2 in consideration of the arrangement of the electrode plates .

The shape of the connection portion 4 is not particularly limited but is sufficiently supplied to the vicinity of the connection portion 4 in such a manner that the electrolytic solution is sufficient so that the cooling of the connection portion 4 is more important, It is important to flow as fast as possible. Therefore, it is preferable that the electrolytic solution is laminar in the vicinity of the connecting portion 4. For this purpose, it is preferable that the connecting portion 4 has a minimum edge or deformation portion. 3, the shape of the cross section perpendicular to the energizing direction of the connecting portion 4 is preferably circular, elliptical, or the like having no corner, that is, the connecting portion 4 preferably has a circular or elliptical shape Do. As a result, turbulence does not occur in the flow of the electrolyte around the connection portion 4, laminar flow occurs, and the flow of the electrolyte around the connection portion 4 is promoted, and a high cooling effect can be obtained.

The electrode surface temperature of the electrode structure 1 is preferably less than 6 占 폚, more preferably less than 5.5 占 폚, particularly preferably less than 5 占 폚, from the viewpoint of prolonging the life of the electrode Is preferable.

<Electrolysis tank and electrolytic condition>

When the electrode structure 1 is used as an anode for plating, the electrode structure 1 is used as a positive electrode and the material to be plated (not shown) is used as a negative electrode, and placed in an electrolytic bath (not shown). The material to be plated is, for example, a coil, a plate, or a wire of a conductive metal such as iron, steel, copper, or nickel. The distance between the anode and the cathode can be appropriately changed according to the plating condition, but may be, for example, 10 mm to 50 mm. Further, an energizing cable (not shown) is mounted on the power supply rear face 3B. The conditions such as the kind, concentration and liquid amount of the electrolytic solution can be appropriately changed depending on the intended use of the electrode structure 1, although generally used conditions of the electrolytic solution can be used. The temperature of the electrolytic solution can be maintained at a desired temperature, for example, by circulating the electrolytic solution between the electrolytic bath and the heater provided outside the electrolytic bath. For example, in the case of high-speed zinc plating, the temperature can be maintained at about 60 ° C. The electrolytic conditions can be appropriately changed according to the intended use of the electrode structure 1. For example, the electrolytic conditions of high-speed zinc plating can be set to a current density of 100 A / dm ^{2 to} 500 A / dm ² .

<Electrode life>

When the electrode structure 1 according to the present embodiment is used as an anode for electrolytic plating, its electrode life is 1.5 times or more, more preferably 1.5 times or more as compared with the case where the electrode structure 1 having no gap C1 is used Can be extended more than two times.

(Second Embodiment)

Hereinafter, another embodiment according to the present invention will be described in detail. In the description of these embodiments, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

The electrode plate boss portion 41A is formed on the segment electrode plate 21 side as shown in Fig. 2 in the first embodiment. However, as shown in Fig. 4, And the boss portion 41B may be formed. 5, the electrode plate boss portion 41A and the power supply boss portion 41B may be formed on both the segment electrode plate 21 and the feeder 3, respectively. 4 and 5, the segment electrode plate 21 and the feeder 3 are in contact with each other at the contact surfaces 44 and 45, respectively.

(Third Embodiment)

In the first and second embodiments, the segment electrode plate 21 and the feeder 3 are configured to contact each other at the contact surfaces 44 and 45. However, from the viewpoint of increasing the strength of the connection portion 4, It is also possible to adopt a constitution in which both are joined via a washer 48 between the electrode plate side contact surface 44 and the power supply side contact surface 45 as shown in Fig. In this case, since the contact surfaces 44 and 45 contact the surfaces of the washer 48, respectively, the contact surfaces are increased. Therefore, in order to suppress heat generation at these contact surfaces, It is preferable to use a metal washer 48 having the same flexibility and corrosion resistance. Specifically, the washer 48 may be made of a platinum group metal such as Ta, Ta / Nb alloy, platinum, palladium, or gold. It is preferable that the surface of the washer 48 is subjected to energization holding treatment such as formation of a platinum film, for example.

Example

Next, concrete examples will be described.

(Electrode surface temperature measurement test 1)

&Lt; Example 1 &gt;

As the electrode plate 2, one surface of a titanium plate having a length of 200 mm and a width of 200 mm and a thickness of 15 mm was coated with an electrode made of Ir / Ta oxide and having a thickness of about 20 탆. A titanium plate having a length of 200 mm, a width of 200 mm and a thickness of 30 mm was used as the feeder 3. As the connecting portion 4, there is formed a steel boss portion having a diameter of 55 mm and a height of 3 mm at the center of the feeder 3, and a bolt hole for fastening M12 bolts is formed at the center thereof, Machined to planarize, and plated to a thickness of 0.1 탆 to obtain a contact surface on the side of the filler. The electrode back surface of the electrode plate 2 was machined and smoothed. In the center of the electrode plate 2, a bolt insertion through hole for mounting a feeder is formed. The electrode plate 2 was mounted and fixed to the power supply boss portion of the feeder 3 by M12 titanium bolts inserted into the bolt insertion through holes. Here, the distance between the electrode plate 2 and the feeder 3 is 3 mm.

Then, the PR thermocouple was welded in the vicinity of the bolt position of the electrode surface of the electrode plate 2, and the welded portion was sealed with an epoxy resin.

The electrode structure 1 thus prepared was used as an anode and a top electrode and a zirconium plate having a length of 200 mm and a width of 200 mm as a negative electrode and a lower electrode and disposed parallel to each other with a gap of 20 mm therebetween, 3) was placed in the electrolytic cell so that the upper part of the electrolytic cell was 10 mm outside. The power supply cable 3 is mounted on the back surface of the power supply 3. A 150 g / L aqueous sulfuric acid solution was used as the electrolytic solution, and the electrolytic solution temperature was set at 60 캜. The amount of electrolytic solution was set at 50 L. The solution was circulated between heater portions to maintain the temperature at 60 캜. Then, electrolysis was performed at a current density of 1000 A (current density 250 A / dm ² ), and the electrode surface temperature was measured. The current density of the connection portion was 0.42 A / mm 2. At the electrolysis time of 20 minutes, the surface temperature of the electrode was almost constant, and the electrode surface temperature at that time was taken as the measured value.

&Lt; Comparative Example 1 &

The same procedure as in Example 1 was carried out except that the electrode fixing portion of the feeder was flat and the electrode front face with the electrode back face was mechanically machined and fixed with M12 bolts in the same manner.

<Results and Discussion>

The electrolytic solution temperature in Example 1 and Comparative Example 1 was 60 ° C.

In Example 1, the measurement value of the surface temperature of the electrode was 62 캜, which is almost the same as the temperature of the electrolytic solution.

On the other hand, in Comparative Example 1, the measurement value of the surface temperature of the electrode was 66 캜, which was 6 캜 higher than the electrolyte solution temperature. In the structure of Comparative Example 1, since the flow of the electrolytic solution around the electrode back surface and the connection portion is suppressed, cooling is not performed on the back surface of the electrode plate and cooling is performed only on one side of the electrode surface exposed to the electrolytic solution. .

(Electrode surface temperature measurement test 2)

&Lt; Comparative Example 2 &

As shown in Fig. 7 and Fig. 8, the segment electrode plate 21 was coated with an electrode of a thickness of about 20 mu m made of Ir / Ta oxide on one side of a titanium plate having a length of 100 mm and a width of 100 mm and a thickness of 15 mm Four electrode surfaces 21A were formed. Since the connecting portion 4 is formed at the center of the electrode of the segment electrode plate, an electrode plate boss portion having a diameter of 25 mm and a height of 2 mm is formed, and an M10 titanium bolt fastening bolt insertion hole is formed in the center of the electrode plate boss portion Respectively. The surface of the electrode plate boss portion other than the bolt insertion through-hole was machined and smoothed to obtain the electrode plate side contact surface.

On the other hand, a titanium plate 210 mm long × 210 mm wide and 30 mm thick was used as the feeder 3. In order to form the connecting portion 4, four solidified boss portions each having a diameter of 26 mm and a height of 2 mm were formed on one surface of the titanium plate so as to correspond to the positions where the electrode plate boss portions were arranged. A bolt hole having a diameter of 12 mm was formed at the center of the full boss portion, and the surface other than the bolt hole was smoothed by machining to obtain a contact surface on the feeder side.

As shown in Figs. 7 and 8, the four segment electrode plates described above were mounted and fixed by M10 bolts 43 to obtain an electrode structure 1. The four segment electrode plates 21 mounted at this time were parallel to each other, and the interval between the adjacent segment electrode plates 21 was 2 mm. The distance between the segment electrode plate 21 and the feeder 3 is 4 mm.

Next, a PTFE plate (not shown) capable of filling the clearance C1 between the electrode plate and the feeding electrode was prepared by disposing it between the four segment electrode plates 21 and the feeder 3. Further, a PTFE plate (not shown) capable of filling the gap C2 between the adjacent segment electrode plates 21 was prepared.

The electrode structure 1 was fixed to the same electrolytic cell as that in Example 1 by filling the gap C1 and the gap C2 with the positive electrode. The cathodes were similarly placed on the bottom of the electrolytic cell using zirconium plates. The electrode structure 1 was placed on the upper side at a distance of 20 mm between the electrodes, and zirconium cathode was provided in parallel with the electrode structure 1. A PR thermocouple was attached to one of the four segment electrode plates 21 near the center of the electrode plate 2 and the surface temperature of the electrode was measured.

The electrolytic solution was an aqueous solution of 150 g / L sulfuric acid + 50 g / L sodium sulfate (Na ₂ SO ₄ ), and the temperature was 60 ° C. Electrolysis was performed by flowing a current of 300 A (current density of 300 A / dm ² ) to each electrode plate. The current density of the connection portion was 0.61 A / mm 2. The electrolysis time was 20 minutes, and the temperature of the surface of the electrode plate was measured.

&Lt; Example 2 &gt;

The measurement was carried out in the same manner as in Comparative Example 2 except that the PTFE plate filling the gap C1 between the segment electrode plate 21 and the feed electrode 3 was removed.

&Lt; Example 3 &gt;

The PTFE plate filling the gap C1 and the PTFE plate covering the gap C2 between the adjacent segment electrode plates 21 were removed in the same manner as in Comparative Example 2. [

<Results and Discussion>

The results of Comparative Example 2 and Examples 2 and 3 are shown in Table 1.

[Table 1]

In Comparative Example 2, since the cooling is not performed on the back surface of the segment electrode plate, it is considered that the temperature has greatly increased.

In Embodiment 2, by removing the PTFE plate that fills the gap C1 between the segment electrode plates and the power supply members, the electrolyte flows to the back side of the segment electrode plate 21 to serve as a cooling liquid, It is considered that the temperature has decreased to the vicinity of the temperature.

Further, in the third embodiment, the PTFE plate for covering the gap C2 between the segment electrode plates 21 in the state of the second embodiment is further removed, whereby the surface temperature of the electrode is further lowered. This is considered to be because the liquid circulation is generated through the space between the segment electrode plates, the liquid circulation is further improved, and the cooling effect by the flow of the electrolyte solution is improved.

(Electrode surface temperature measurement test 3)

&Lt; Examples 4 to 7 and Comparative Example 3 &gt;

Using the electrode structure 1 shown in Fig. 9 and Fig. 10, electrolysis was carried out under the same conditions as in Comparative Example 2, and the change of the surface temperature of the electrode according to the distance between the electrode plate and the feeding electrode was examined.

The configuration of the electrode structure 1 shown in Figs. 9 and 10 is the same as that of the comparative example 2 shown in Figs. 7 and 8, except for the following points.

9 and 10, the PTFE sealing 6 is performed along the outer periphery of the segment electrode plate 21 and the feeder 3, and the flow of the electrolyte is controlled by the interval between the segment electrode plates 21 (C2). Thus, even if the distance between the electrode plate and the feeding electrode changes, the flow rate of the electrolytic solution flowing into the gap C1 is made constant.

From both sides of the electrode plate side contact surface 44 of the segment electrode plate 21 constituting the connecting portion 4 and the feeder side contact surface 45 of the feeder 3 in terms of reducing the electrical resistance, Platinum plating was carried out. Then, a platinum-coated tantalum washer 48 was disposed between the contact surfaces 44, 45. The distance between the electrode plate and the feeder is adjusted by adjusting the thickness of the washer 48 in the range of 5 mm to 25 mm.

Table 2 and Fig. 11 show the results of measuring electrode surface temperature rise in accordance with the change of the distance between the electrode plate and the feed electrode of the electrode structure 1 of Examples 4 to 7 and Comparative Example 3.

[Table 2]

As the distance between electrode plate and feed electrode increased from 5 mm to 25 mm, the electrode surface temperature gradually increased. This is considered to be due to the fact that the liquid flow rate around the connection portion 4 is reduced due to an increase in the distance between the electrode plate and the feeding electrode, and the heat generation amount of the connection portion 4 is increased.

(Electrode life test)

&Lt; Example 8 and Comparative Example 4 &gt;

In order to confirm that the life of the electrode was prolonged as cooling was performed on the back surface of the electrode plate 2, an operation test was actually performed in a continuous high-speed zinc plating line.

That is, the electrode structure 1 of Example 8 was prepared as follows. As the segment electrode plate 21, a titanium plate having a length of 200 mm and a width of 200 mm and a thickness of 20 mm was coated with an electrode made of Ir / Ta oxide and having a thickness of about 20 占 퐉 to form an electrode surface. A part of the back surface of the electrode of the segment electrode plate 21 was machined to form two electrode plate boss portions each having a height of 4 mm in the circumferential direction and the distance between the segment electrode plates was 3 mm, Bolts were fastened.

As the electrode structure of the comparative example 4, the electrode back surface of the segment electrode plate was smoothed and directly bolted to the smooth power supply.

The electrolytic solution was a high-speed zinc plating bath (ZnSO ₄ , 200 g / L) and the electrolyte temperature was 60 ± 2 ° C. A steel sheet was used as the material to be plated. The electrolytic current density was 120 A / dm ^2, and the electrolytic current density was set as an electrode of a plating line to conduct continuous electrolysis.

<Results and Discussion>

The electrode structure having no gap between the segment electrode plate of the comparative example 4 and the feed electrode has reached the end of its useful life in three months. On the other hand, it was found that the initial performance was maintained even after 9 months or more with the gap of 4 mm between the full-electrode plates of Example 8.

The present invention is very useful because it can reduce deterioration of the electrode structure by alleviating the influence of the temperature rise of the electrode structure itself and can provide an electrode structure having a long electrode life.

1: Electrode structure 2: Electrode plate
21: segment electrode plate 21A: electrode surface
21B: Electrode surface 3: Feed electrode
3A: grade surface 3B: grade grade
4: Connection
41A: electrode plate boss portion (convex upper portion)
41B: full boss portion (convex upper portion)
42: bolt insertion through hole 43: bolt (mounting member)
44: electrode plate side contact surface (contact surface) 45: feed side surface (contact surface)
46: Bolt hole 48: Washer
C1: clearance C2: clearance
C21: first spacing C22: second spacing

Claims (10)

An electrode plate made of titanium or a titanium alloy,
The electrode plate
And,
Wherein the electrode plate and the power supply member are tightly fixed via a connection portion,
A gap is formed between the electrode plate and the power supply member so that the electrolyte solution can pass between the electrode plate and the power supply member other than the connection portion when the electrode plate is immersed in the electrolyte solution,
And the gap between the electrode plate and the feeder is 1 mm or more and 20 mm or less. The method according to claim 1,
Wherein the electrode plate comprises a plurality of segment electrode plates divided into a plurality of segments,
And an interval of 1 mm or more and 3 mm or less is formed between adjacent segment electrode plates. The method according to claim 1 or 2,
Wherein the electrode plate comprises a plurality of segment electrode plates divided into a plurality of segments,
Wherein the connecting portion comprises:
A convex portion formed on at least one of the segment electrode plate and the feed electrode,
And a mounting member for mounting and fixing the electrode plate and the feeding member on the convex portion. The method of claim 3,
Wherein the mounting member is a bolt. The method according to claim 1 or 2,
Wherein a current density of the connection portion is 0.3 A / mm &lt; 2 &gt; or more and 1.0 A / mm &lt; 2 &gt; or less when the electrode plate is energized with a rated current through the feeder. The method according to claim 1 or 2,
Wherein the shape of the cross section perpendicular to the energizing direction of the connecting portion is a shape in which the flow of the electrolytic solution passing through the gap when the electrode plate is immersed in the electrolytic solution in a state where the electrode plate is fixedly mounted on the feed electrode is a laminar flow Structure. The method according to claim 1 or 2,
Wherein an interface between the electrode plate and the feeder in the connection portion is covered with a platinum group metal. The method according to claim 1 or 2,
And the electrode plate and the feeding member in the connecting portion are joined to each other with a washer interposed therebetween. The method of claim 8,
Wherein the washer is made of tantalum coated with platinum on its surface. The method according to claim 1 or 2,
Wherein the electrode structure is an anode for electrolytic plating.

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