KR200314574Y1 - Electrochemical cell for removal of metals from solutions - Google Patents

Abstract

The present invention relates to an electrochemical cell for removing metal from a solution, comprising an outer casing 10 and a cathode assembly 21 disposed centrally in the outer casing 10, spaced apart from the cathode assembly 21. An anode assembly 22 disposed inside the outer casing 10 and a flow inlet 13 and an outlet 14 of the electrolytic solution, the cathode assembly 21 having permeable stretch support having a circumferential circumference; The member 27 is provided with a permeable cathode portion 26 made of a permeable carbon fiber material disposed on the permeable elongate support member 27 and extends along the entire length of the permeable cathode portion 26. Cathode current feeder post 17 held on top of the electrolyte flows through flow inlet 13 and exits through flow-through cathode portion 26 toward flow outlet 14 to remove at least one metal from the electrolyte.In the electrochemical cell of removal in a solution manner, the cathode current feeder post 17 consists of a plurality of current feeder strips 28, each extending along the length of the permeable cathode portion 20, the current feeder strip ( 28) is arranged evenly with respect to the circumference of the elongate support member 27, the total size of the width (W) of the structure is made of about 20% of the circumferential size of the elongated support member (27).

Description

ELECTROCHEMICAL CELL FOR REMOVAL OF METALS FROM SOLUTIONS

The present invention relates to an electrochemical cell for removing metal dissolved in a solution. For example, an electrochemical cell for recovering precious metals from a solution protects a waste environment and removes harmful metals from waste water. It is about.

Various electrochemical cells are well known for recovering metals from common diluent solutions such as wastewater or wastewater to electroprecipitate metals in solution, such cells are described, for example, in US Pat. No. 5,690,806, The cell was provided with an outer casing with a cathode in the shape of a cylindrical portion of carbon fiber material surrounding the network through support of the open structure.

The long current feeder located in the longitudinal direction of the tubular support provides a flow to the carbon fiber cathode, wherein the cathode assembly is surrounded by an aggregate tubular anode spaced from the cathode, so that the metal The removed electrolytic solution is led into the cell through the inlet and flows along the flow passage to the outlet through the porous or permeable carbon fiber cathode, whereby the associated metal is allowed to precipitate on the surface of the carbon fiber constituting the cathode.

Typically such cells are limited by the consumption of ions of the electrolyte in which the maximum flow density is in close contact with the surface of the electrode on which the material is deposited, i.e., in the cell of US Pat. Although it had a greatly increased surface area as an effective shape for the removal of metal ions, although the performance and efficiency of the cell was improved, practical improvements were needed for large-scale industrial use.

The present invention provides an electrochemical cell for removing metal from a solution that achieves the industrial practical improvement of US Pat. No. 5,690,806 described above.

It is an object of the present invention to provide an electrochemical cell with an improved current feeder, the current feeder having a structure that makes it easier to remove the used cathode.

And another object of the present invention is to have an electrochemical cell having an anode structure that obstructs the flow of gas along the cylindrical wall behind the anode.

Another object of the present invention is to provide an electrochemical cell with an easy removal module divider that can be further prevented from decomposition into a harmful environment while forming two separate passages for the anode and the cathode. The same cell is equipped with a module replacement tip cap assembly to enable it to handle different flow requirements without changing the cathode to anode assembly.

This object of the present invention is achieved by applying the permeable carbon fiber cathode supported to an open structure of the elongated support member to the general cell described in US Pat. No. 5,690,806 described above.

The cathode current feeder according to the present invention consists of a plurality of feeder strips each extending in the longitudinal direction of the permeable cathode, which feeder strips are arranged evenly around the elongated cathode support member. The feeder strips also have an aggregate total width of about 20% in the characteristic circumferential size of the cathode support member.

Moreover, feeder strips can be formed to avoid obsolete electrodeposition in current feeder strips to comply with the curvature of the cathode support member and to avoid obstacles that prevent the removal of the used cathode from the support member.

The cell of the present invention also has an anode spaced from the inner wall of the outer casing at least approximately 2.5 mm apart, and is intended to provide an effective means of preventing the gas formed between the anode and the outer casing.

The cell of the present invention provides an improved micropermeable divider disposed between the cathode and the anode to separate the anolyte and catholyte flow chambers.

The divider here consists of a micropermeable membrane sandwiched between two permeable support sleeves which hold and protect the membrane in order to extend its life and to limit its flexible movement during use.

In addition, the present invention has a definite modular structure while being easily adapted to different flow rates.

1 is an overall perspective view of an electrochemical cell according to the present invention,

2 is a cross-sectional view taken along line II of FIG. 1;

3 is a perspective view of a cathode assembled in the present invention,

4 is a cross-sectional view of FIG.

(A) is sectional drawing along the II-II line | wire of FIG.

5B is a cross-sectional view of another embodiment of line II-II of FIG. 3;

6 (a) and 6 (b) are exploded views showing another embodiment of the distal end caps of the divider assembly.

Explanation of symbols on main parts of drawing

10: outer casing, 11, 12: tip cap,

13: flow inlet, 14: flow outlet,

16: toggle bolt, 17: cathode feeder post,

18: anode feeder post, 19: anolyte flow outlet,

21: cathode assembly,

22: anode assembly,

23: divider, 26: cathode portion,

27: extension support member, 28: current feeder strip,

29: outer cover, 31: round end piece,

32: first annular baffle plate, 33: second annular tip piece,

36: spacing ring, 37: bracket,

38: plug, 39: opening,

41: membrane, 42, 43: sleeve,

44, 45: round end piece, 46: 0 ring,

48, 49: engaging annular portion, 51, 52: inclined wall,

53: 0 ring, 56: the third annular portion,

57: bolt, 58: hole,

61,62 module insertion part.

Hereinafter, the present invention will be described in detail based on the accompanying drawings.

1 and 2 are views showing the outside and inside of the electrochemical cell according to the present invention, the cell of the present invention is provided with a housing structure that is usually a cylindrical outer casing 10, both ends of the outer casing 10 End caps 11 and 12 are installed at the end.

Here, one of the lower front end caps 11 has a flow inlet 13 (see FIG. 2), and the other upper front end cap 12 has a flow outlet 14.

The solution under treatment enters the cell through the flow inlet 13 in a continuous flow and is discharged to the flow outlet 14 whereby the associated metal ions are electrochemically removed.

Also shown in FIG. 1 are a number of toggle bolts that can safely remove the outer casing 10, the cathode current feeder post 17, the anode current feeder post 18, and the anolyte flow outlet 19 of the cell described below. It can be seen that 16) is installed.

All these mechanical elements 16-19 are located on the upper tip cap 12 without protruding backwards around the periphery of the tip cap without protruding to the cylindrical side of the outer casing 10.

This structure is of considerable practical use to avoid leakage during use of the cell, for example during installation or replacement of the cathode member.

The electrochemical cell is equipped with a cathode assembly 21, an anode assembly 22 and a divider 23 disposed therebetween to separate the flow of the cathode assembly 21 and the anode assembly 22.

The divider 23 is an optional structure used for preventing exposure of the catholyte to the anode assembly 22. For example, induced chlorine gas can be produced at the anode and it is desirable to prevent the production of such gas for safety reasons.

Specifically, the divider 23 is a module that can be removed from the cell and easily inserted into the cell when its use is required or not required.

The structure and operation of this divider 23 will be described in more detail below.

The cathode assembly 21 includes a permeable cathode portion 26 supported by the permeable elongate support member 27 as shown in FIGS. 3 to 5, and a plurality of cathode currents in electrical contact with the cathode portion 26. It consists of a feeder strip 28.

The cathode portion 26 is a well-known technique as described in US Pat. No. 5,690,806, which is made of a permeable carbon fiber material and has a permeable structure having a large surface area by volume ratio.

In this case, the carbon fiber material is formed in a flat felt-to-mat shape in a roll shape with a size wrapped around the elongate support member 27. And, if necessary, the carbon fiber material has a hollow cylinder shape for installation on the elongate support member 27.

Specifically, the elongate support member 27 is a cylinder of circular cross section and has a general tubular shape as shown in FIGS. 2 and 4 and 5 (a) (b).

The elongate support member 27 is of sufficient porosity through which the electrolyte solution passes through the support member, and as shown, this porous permeability is the tubular wall of the elongate support member 27 like an open mesh or grid pattern. To form.

On the other hand, it can also be used in other structures, for example, the elongate support member 27 may be formed of a hollow cylinder or permeable polyethylene, or may be made of a suitable filter cloth of an open structure that is adjusted to the selection of the flow filter. have.

In the present invention, even if the elongate support member 27 is a conductor in another technology, the elongate support member 27 is a non-conductor and has a form to help the current feeder function.

On the other hand "invasive" in the present invention is used in the most general sense that can penetrate. Thus, the permeable support member is a support member having suitable openings through which the electrolyte solution permeates in the desired flow.

The "small holes" of the elongate support member 27 are provided by a large cell of the mesh structure as shown in the drawing or may be a small hole in the filter cloth or a large or small perforation of the support member wall.

The carbon cathode member is permeable which has the same function as the electrolyte solution to penetrate the carbon material, and the "small holes" of this permeable carbon cathode member are also in large or small proportions depending on the special material selected for the cathode member. It does not have the same size or shape as the small holes of the extension support member 27. It can be seen that the small holes of the cathode member are smaller than the small holes of the support member and are formed by the gaps and spaces of the carbon fiber material forming the cathode member.

The current feeder is electrically connected to the cathode member, and effective electrolysis is achieved, as is well known in US Pat. No. 5,690,806, in particular metal deposition is uniform on the cathode member.

In addition, it is preferable to provide a uniform distribution of current to the cathode member.

In the present invention, the cathode current feeder is provided with a plurality of current feeder strips 28 disposed evenly around the periphery of the cathode extension support member 27, and the cathode portion 26 is installed along the length direction, and the circumferential size, that is, the extension Compared with the space | interval of the circumference of the support member 27, it has a collective width.

Moreover, the collective width of the strips should be about 20% of the circumferential size of the stretch support member 27.

It can be seen that it is effective when preferably having a collective width of about 25% in the circumference size.

This arrangement provides the advantage of reduced heat generation due to uniform current distribution, more metal settling, and reduced resistance in the current strip.

5 (a) and 5 (b) are different embodiments showing the installation states of two current feeder strips 28 arranged opposite to each other around the extension support member 27. As shown in FIG. However, more than two current feeder strips 28 may be disposed as desired.

The current feeder strip 28A shown in FIG. 5A is flat and has a width W, the total width of which is 2W greater than about 20% on the circumference of the extension support member 27. The current feeder strip 28B shown in FIG. 5B is curved along the circumference of the extension support member 27. The purpose of this curved structure will be described later, but in operation the relevant metals are deposited on the interstitial surfaces of the permeable carbon cathode members. After the operation is completed, the cathode member is replaced by dropping the deposited metal.

This opens the cell with the upper tip cap 12 and then removes the entire cathode assembly. The dropped cathode portion 26 is slid off from the extension support member 27, and then replaced with a new cathode member.

However, sometimes the loaded cathode member is hung on the edge of the current feeder strip 28A shown in Fig. 5 (a), partly because of the small amount of metal which is deposited at the exposed bottom of the current feeder strip 28A. As a result, in this case, the dropped cathode member can be easily separated by the current feeder strip 28B conforming to the shape of the extension support member 27 as shown in FIG.

Although the elongate support member 27 is shown in a cylindrical shape for easy separation of the loaded cathode member, the elongated support member may be thin tapered, in which case the cathode member is generally cylindrical and hollow. In order to fit with the tapered portion of the elongate support member, it is slightly tapered.

The circumferential size of the elongate support member may vary depending on the position measured along the length of the elongate support member. However, it can be seen that only a small taper shape is possible and the variation in the circumference is small.

Any size of circumferential size along the elongate support member, e.g., at intermediate length, may be a specific circumference that can be determined to accommodate the total width of the current feeder strip 28.

As shown in FIG. 3, the cathode portion 26 is firmly attached to the extension support member 27 by a conventional mesh-like sheath 29.

This sheath 29 is in the form of a resin sheath netting or a resin tie to attach the cathode to the support member, as is well known in US Pat. No. 5,690,806.

The sheathing cover 29 provides better electrical contact and current distribution, even though it is sized appropriately with an elastic material for uniform pressing of the cathode portion 26 against the current feeder strip 28.

Such an elastic sheath 29 induces smooth operation during work and weakens the strain caused by the cathode portion 26.

The cathode assembly 21 is connected to the annular tip 31 at the inlet side of the cathode assembly with a laterally projecting face to hold the cathode portion 26. The flow inlet 13 extends toward the center of the elongate support member 27 through the center of the annular end piece 31, and one end of the current feeder strip 28 is formed by the small screw. This annular tip piece 31 has the advantage that the removal and screw separation from the tip of the elongate support member 27 are simple.

This structure facilitates the removal of the used cathode portion 26 so that the extension support member can be separated.

At the other end of the cathode assembly 21 there is a first annular baffle plate 32 and a second annular tip piece 33 spaced apart from the first annular baffle plate 32. The permeable elongate support member 27 extends to the second annular tip piece 33 behind the first annular baffle plate 32, and the flow outlet 14 opens the hole of the second annular tip piece 33. It is formed through.

Therefore, the electrolyte solution is guided to the center of the extension support member 27 through the flow inlet 13 and is prevented from flowing directly toward the flow outlet 14 by the first annular baffle plate 32.

Therefore, the electrolyte flows through the opening of the permeable elongate support member 27 and the cathode part 26, and at this time, metals are precipitated in the outer space of the cathode part 26.

The solution depleted of the metal component, as shown in the direction of the arrow in FIGS. 2 and 3, is rearward through the permeable stretch support member in the space between the first annular baffle plate 32 and the second annular tip piece 33. Flows out to the flow outlet (14).

The cathode assembly 21 also has two cathode current feeder posts 17 for electrical connection to the current feeder strip 28, the cathode current feeder posts 17 having an upper tip cap for the connection of the electricity supply. The second annular end piece 33 inside the cell, which is an assembly structure extending through 12, is bolted with the current peter strip 28.

On the other hand, the anode assembly 22 is a conductive cylinder while concentrically wrapping it with the cathode assembly 21, the structure and suitable material of the anode assembly is a known technique as described in US Pat. No. 5,690,806 Avoid the above.

That is, the anode known from the US patent is attached to the inner wall of the tubular outer casing and arranged concentrically, and the anode assembly 22 may be spaced apart from the inner wall of the tubular outer casing 10 at a predetermined interval.

This may require a space behind the anode assembly 22 to prevent the formation of gas pockets between the inner wall of the outer casing 10 and the anode assembly 22 and to reduce heat resistance to eliminate heat generation.

The spacing of about 2.5 mm is preferably within 5 mm, and the spacing is made by the spacing ring 36.

In FIG. 2, the spacer ring 36 is equipped with a bolted head for attachment to the anode assembly 22 and the conductive bracket 37.

The conductive bracket 37 is also connected to an anode current feeder post 18, for which the anode current feeder post 18 is helically fastened to the tip of the anode assembly 22, which is an anode current. The feeder post 18 extends through the upper tip cap 12 via the plug 38 for electrical supply.

In some systems, it is desirable to set up an electrochemical cell having an anode and cathode connection at the opposite tip of the cell.

The lower tip cap 11 is provided with an optional pair of anode current feeder openings 39 arranged symmetrically with respect to the openings in the upper tip cap 12 to achieve a system with the same cell. 37) and the anode assembly 22 with the anode current feeder post 18 are simply flipped over and unused pairs of current feeder openings are plugged in.

As described above, when a separate unmixed flow is provided for the catholyte for the cathode and for the anolyte for the anode, the optional divider 23 is inserted between the anode and the cathode assembly.

This known divider 23 is equipped with a micropermeable membrane 41 which allows for the proper movement of ions across the membrane but does not allow water to pass through it.

Conventionally, these micropenetrating membranes tended to be weaker and burst more than desired.

However, in the present invention, the use of the membrane 41 on both sides of a pair of inner and outer permeable support sleeves 42 and 43 increases the life and makes it stronger.

The support sleeves are synthetic tubular members having a network structure or a hole in which the membrane 41 is coaxially disposed between them, and in which the outer sleeves press and hold the membrane 41 from both sides.

This approach minimizes the flexible movement of the membrane during use.

In the embodiment of FIG. 2, the divider 23 has annular tip pieces 44, 45 at each tip side thereof, which tip pieces 44, 45 are stepped, with an inner sleeve 42. And membrane 41 are attached to the first step and the outer sleeve 43 extends to be attached to the next step of the annular piece 44.

In the upper tip piece 45, the inner sleeve 42 extends to the rear of the outer sleeve 43 as shown in FIG. 2.

These membranes and sleeves are tightly joined by a suitable waterproofing binder.

The tip pieces 44 and 45 serve as a seal member that is waterproof to the inlet and outlet extending through the central opening in the annular tip pieces. The tip piece 44 of 2 shows the 0 ring 46.

However, under certain corrosive environments, the bonded membranes 41 and sleeves 42 and 43 are of poor quality, resulting in leaking of the divider assembly. FIGS. 6 (a) and 6 (b) show alternative embodiments of the tip piece. Are shown by reference numerals 44 and 45.

The tip piece 45 'is provided with a pair of engagement annular portions 48, 49 having corresponding inclined walls 51, 52, one on the inclined wall 51 of the inner engagement annular portion 48. The above zero ring 53 is attached.

The membrane (shown in partial view in FIG. 6 (a)) is spread over the zero ring 53 and pressed by the outer engagement annular portion 49, which is joined together and tightened together. Coupled with the three annular portion 56, it is firmly fastened by the bolt (57).

The third annular portion 56 is formed with a hole 58 for the anode current feeder post 18.

On the other hand, the bottom tip piece 44 'is substantially similar to the top tip piece 45', but the third annular part 56 'is like the third annular part 56 in the upper tip piece 45'. Since the width is not required, it is not necessary to prepare for alternative positions of the anode current feeder post, and in FIG. 6 (b), the same reference numeral is added to the same reference numeral in FIG. 6 (a).

The present invention with greater flexibility for use in other applications is that the lower tip cap 11 and the upper tip cap 12 are formed in a modular structure for easy application to different flow rates. The tip cap 11 has a movable module insert 61 having a flow inlet 13.

In the case of other inlet channels, only the replacement of the module insert 61 is required by comparable tip pieces with different inlet holes.

Therefore, the present invention has the upper end cap 12 also has a moving module insert having a flow outlet 14, such a structure, for example, the advantage that can be used quickly and easily for use for maintaining a larger flow amount This makes it quick and simple to replace the insert.

Moreover, the module structure has the advantages of manufacturing, cost and timing since it can be applied to other cells only by changing the insert in the same basic cell.

On the other hand, the present invention has been described with an example with the accompanying drawings, various modifications are possible within the scope not departing from the gist of the present invention, for example, the extension support member 27 is not only a grid shape having a circular cross section It is of course possible to have other geometries.

Claims (3)

An outer casing 10, a cathode assembly 21 disposed in the center of the outer casing 10, an anode assembly 22 spaced apart from the cathode assembly 21 and disposed inside the outer casing 10, and electrolytically A flow inlet 13 and outlet 14 of the solution, wherein the cathode assembly 21 has a permeable stretch support member 27 having a circumferential circumference and is permeable disposed on the permeable stretch support member 27. The permeable cathode portion 26 made of carbon fiber material, the cathode current feeder post 17 held on the elongate supporting member 27 while extending along the entire length of the permeable cathode portion 26, and the electrolyte solution flow inlet. An electrochemical cell which flows in through and passes through the permeable cathode and exits to the flow outlet, removes one or more metals from the electrolyte in an electrolytic manner. The cathode current feeder post 17 consists of a plurality of current feeder strips 28 each extending along the length of the permeable cathode portion 26, the current feeder strips 28 being the circumference of the elongate support member 27. An electrochemical cell for removing metal from a solution, characterized in that the total size of its widths (W) is approximately 20% of the circumference of the elongate support member (27) while being evenly disposed about the perimeter. 2. The solution of claim 1 wherein the elongate support member 27 is tubular and the current feeder strip 28 is flat and tangentially disposed along the width around the circumference of the tubular member. Electrochemical cell to remove metal. The method of claim 1, wherein the cathode portion 26 is provided with a permeable sheath cover 29, the sheath cover 29 is made of an elastic material to compress the cathode portion 26 to be electrically connected with the current feeder strip 28 An electrochemical cell for removing metal from a solution, characterized in that contact is made.