DE102022129543B3 - Electrolysis cell, especially for swimming pool disinfection and its use - Google Patents

Abstract

The disclosure relates to an electrolytic cell, comprising an input and an output and a housing with a plurality of plate-shaped electrodes. The housing provides an annular space into which electrolyte can be introduced from the inlet in such a way that a rotating flow occurs.

Description

Field of invention

The invention relates to an electrolysis cell, which is used in particular to produce chlorine or hypochlorite or bromine or hypobromite for swimming pool disinfection. The invention further relates to a method for producing the electrolytic cell.

Background of the invention

It is known from practice to produce hypochlorite or hypobromite from a salt solution using an electrolytic cell and to use it to disinfect swimming pools. Chlorine produced by the electrolytic cell, in particular hypochorous acid HClO, acts as a strong oxidative agent and thus has a high disinfectant effect.

Known electrolysis cells used for swimming pool disinfection include, for example, a tubular housing in which an electrode pack is arranged. A disinfection system with such an electrolysis cell is sold in particular by the applicant under the trade name BWT Hydrolife 16.

The disadvantage of known electrolysis cells is that the efficiency is only sufficient if the water has a relatively high salt content, usually > 3 g/l NaCl.

Task of the invention

In contrast, the invention is based on the object of providing an electrolytic cell which is of simple construction and which has a high efficiency in terms of current yield and conversion. In particular, the invention is intended to provide an electrolytic cell which can be optimally used for a system for disinfecting swimming pools.

The document EP 0 109 789 B1 shows an electrolytic cell with a vortex generating device in the entrance. The document DE 694 31 724 T2 shows, among other things, hexagonal electrodes for an electrolytic cell.

Task of the invention

The object of the invention is already achieved by an electrolytic cell and by a method for producing an electrolytic cell according to one of the independent claims.

Preferred embodiments and further developments of the invention can be found in the subject matter of the dependent claims, the description and the drawings.

The invention relates to an electrolysis cell. The electrolysis cell is designed in particular for a system for swimming pool disinfection in order to produce free chlorine or free bromine from a salt containing chloride or bromide, or generally from a salt containing halide.

The electrolytic cell includes an input and an output as well as a housing with a plurality of plate-shaped electrodes. The housing provides an annular space.

According to the invention, the electrolytic cell is designed in such a way that electrolyte can be introduced into the space from the entrance in such a way that a rotating flow is created.

According to the invention, the flow around the electrodes, in particular the electrode pack, is not linear, but rather a vortex is created in the space which flows past the plate-shaped electrodes.

It has been shown that this can increase the efficiency of the electrolytic cell. The inventors suspect that the vortex-shaped flow ensures that fresh electrolyte flows around the electrodes in an improved manner, which increases efficiency.

The space can in particular be designed in the shape of a circular cylinder.

The housing can in particular comprise a circular cylindrical section which provides the space and in which the electrodes are stacked.

In one embodiment of the invention, this circular cylindrical space intersects on the shell side with a tubular housing section, which provides the input and the output. Due to the overlap, the circular cylindrical space opens into the tubular section, so that a partial stream of water can flow into the space and form a vortex there.

Between the input and output, the flow of electrolyte is divided into two partial streams. A first partial stream flows directly to the output, while part of the salt solution or swimming pool water passes through the electrode pack in a vortex shape in a second partial stream.

Due to its design, the bypass is already integrated into a compact housing and there is no need for an additional bypass.

The electrolysis cell is in particular designed in such a way that the electrolyte flows into the room tangentially or secantially. The plate-shaped electrodes are stacked parallel to the base of the circular cylindrical space and spaced apart from one another.

The electrodes preferably protrude from the room into the input current. In particular, the stacked electrodes of the electrode pack protrude into the tubular section which overlaps with the space.

The electrolysis cell preferably has an electrode pack with a large number of stacked electrodes, in particular 3 to 10 electrodes.

Inner electrodes of the electrode pack can be arranged as bipolar electrodes. Bipolar electrodes are not connected to the electrical connections of the electrolytic cell. The bipolar connected electrodes are free in the room and are surrounded by electrolyte. The bipolar electrodes serve as reaction carriers.

This arrangement ensures a particularly simple structure of the electrolytic cell.

For the production of chlorine or bromine for swimming pool disinfection, the electrolysis cell is preferably designed as a one-piece, i.e. undivided, electrolysis cell.

Instead of a bipolar arrangement of the inner electrodes of the electrode pack, in another embodiment of the invention they are connected in parallel and/or in series.

In one embodiment of the invention, the electrodes sit in holders or frames which are stacked in the space of the housing.

The holders can in particular include fingers for holding the plate-shaped electrodes. In particular, the holders can be designed annularly, in particular circularly.

Furthermore, the holders preferably include spacers and can be stacked on top of one another, in particular plugged onto one another, so that the individual plate-shaped electrodes are positioned at a defined distance from one another via the holders in the housing. The spacers can be designed as webs, for example. Water can flow through the electrode pack with the holders from the jacket side. The holders form a kind of grid through which water can flow.

In a further development of the invention, the electrodes are polygonal. In particular, the electrodes are triangular, square or hexagonal.

This geometry has the advantage that the electrodes are produced by separating them from a plate material, with no waste occurring between the individual electrodes. In particular, the hexagonal design closely approximates the circular cylindrical shape of the housing.

The invention further relates to an electrolytic cell, in particular an electrolytic cell with the features described above.

This includes an input and an output as well as a housing with a plurality of plate-shaped electrodes, the housing providing a space with the electrodes. In particular, the room contains an electrode pack with a large number of electrodes.

An electrolyte can be introduced into the space with the electrodes. According to the invention, the space comprises an electrolyte inlet, via which the electrolyte can be introduced through the space via the electrodes into a main current.

In this embodiment of the invention, the electrolysis cell therefore comprises a housing through which a main stream, in particular a circulation line from a swimming pool, is passed.

The room is connected to the main stream in such a way that electrolyte can flow from the room into the main stream.

The housing further comprises a further inlet, namely an electrolyte inlet, via which electrolyte can be conducted directly into the room. Using the electrolyte, free chlorine or bromine, for example, is produced in the room and then fed into the main stream.

This configuration enables a particularly simple provision of an electrolytic cell without an additional bypass.

In particular, it can be the electrolysis cell described above, which includes an additional electrolyte inlet that leads into the space with the electrode pack.

The electrolyte inlet can be used in particular to generate chlorine or bromine from an electrolyte concentrate and to introduce this into the main stream.

The concentrated electrolyte can be provided, for example, via a salt separation system through which the swimming pool water is passed. This can in particular be a reverse osmosis system.

The salt separation system produces low-salt water, which is fed back into the swimming pool, as well as concentrated electrolyte, which is metered into the electrolytic cell via the electrolyte inlet.

In one embodiment of the invention, it is particularly provided that an insert part is inserted in the main stream, which provides an output for the space with the electrodes.

The insert part is preferably designed to be removable and is used when the electrolytic cell is to be connected to the electrolyte inlet.

If the swimming pool water is used directly as electrolyte, the insert can be omitted and the electrolyte inlet is not connected. With this use, there must be a vortex in the space of the electrolytic cell and chlorine or bromine is produced directly from the swimming pool water.

If, on the other hand, the electrolysis cell is used to produce chlorine or bromine from an electrolysis concentrate, for example a salt separation system, the insert part is inserted and provides the exit from the room with the electrodes.

The insert can in particular be designed as a cover, which reduces the opening between the main stream and the space with the electrodes. No significant amount of water now flows into the room from the main stream, but electrolyte concentrate is fed into the room via the electrolyte inlet and the water enriched with free chlorine or bromine enters the main stream via the insert.

The invention further relates to a method for producing an electrolytic cell, in particular an electrolytic cell as described above.

According to the invention, a plate-shaped electrode material made of a coated metal is provided.

The electrodes can in particular be made of coated titanium, tantalum or nickel and include a conductive oxide layer.

For example, iridium oxide and/or ruthenium oxide or platinum can serve as the conductive oxide layer.

The material of the plate-shaped electrode can, for example, have a thickness of 0.5 to 2 mm.

According to the invention, this material is divided into polygonal, in particular hexagonal, electrodes, which are then inserted into a housing of the electrolysis cell.

In particular, the electrodes can be punched out, laser cut or water jet cut.

The use of a hexagonal shape enables production with almost no waste.

Rather, a material such as titanium is preferably used, which oxidizes on the edge and thus forms an oxidizing protective layer. The cutting edge is thus passivated.

This even has the advantage that an electrode is automatically provided which has a material with lower electrical conductivity on the edges than on the front and back.

Brief description of the drawings

• 1 ist eine perspektivische Ansicht einer erfindungsgemäßen Elektrolysezelle.
• 2 ist ein Längsschnitt der Elektrolysezelle.
• 3 ist ein Querschnitt der Elektrolysezelle.

The subject matter of the invention will be described below with reference to the drawings 1 until 5 will be explained in more detail using an exemplary embodiment.

• 1 is a perspective view of an electrolysis cell according to the invention.
• 2 is a longitudinal section of the electrolysis cell.
• 3 is a cross section of the electrolysis cell.

Referring to the sectional views according to 4 and 5 The use of the electrolytic cell is intended to be used for a concentrate, with an insert being inserted into the main stream of the electrolytic cell.

Detailed description of the drawings

1 shows a perspective view of an exemplary embodiment of an electrolytic cell 1 according to the invention. The electrolytic cell 1 comprises a housing 10, which provides a substantially circular cylindrical space 13, which is closed with a cover 11.

The cover 11 can in particular be designed as a screw cover.

The housing 10 further comprises a pipe section 14, which provides an input 15 and an output 16.

By means of the pipe section 14, the electrolysis cell 1 can be installed in particular in the circulation line of a swimming pool.

The housing 10 is thus formed by a circular cylindrical space 13, which intersects with the pipe section 14 on the jacket side.

The lid 11 includes star-shaped webs 12, which serve as stiffening webs or handles for screwing the lid 11 on and off. An electrical connection 3a for connecting an electrode protrudes from the housing 10, more precisely from the cover 11.

2 is a longitudinal section approximately in the middle through the pipe section 14.

Plate-shaped electrodes 2 are stacked on top of each other in the circular cylindrical space 13.

The space 13 overlaps with the pipe section 14, so that the space 13 is open to the side of the pipe section 14.

The electrolyte flowing in via the entrance 15 flows partially into the space 13, in which a vortex forms. The flow directions are marked with arrows.

Electrolyte, which leaves the vortex again, flows back into the main stream and leaves the electrolytic cell 1 via the outlet 16.

The annular holders 20, which are inserted into the space 13, are also shown.

In this exemplary embodiment, the holders 20 include fingers 21 which grasp and hold the electrodes 2 at the corners.

The holders 20 also include spacers 22, which serve for a defined distance between the holders 20 and thus the electrodes 2.

The space 13 preferably has a diameter of 50 - 200 mm (inner diameter).

On the side opposite the pipe section 14, the housing 10 includes the electrolyte inlet 17.

The electrolyte inlet 17 can in particular include a check valve and can be used alternatively if the electrolyte is not to be supplied via the inlet 15, but rather, for example, as a concentrate via the electrolyte inlet 17 (see 4 and 5 ).

3 is a cross section of the electrolysis cell.

The housing 10 is shown, which also has star-shaped webs 12 on the side opposite the screwed-on cover.

The electrical connections 3a, 3b are led out of the middle of the room 13. These are sealed in the housing 10, in particular one of them in the cover 11 of the housing 10.

The outer electrodes 2a and 2e are contacted via the electrical connections 3a, 3b.

The inner electrodes 2b - 2d, on the other hand, are arranged bipolar and only serve as reaction carriers.

The electrodes 2a - 2e are inserted into the holders 20a - 20f. The holders 20a - 20f are plugged together and, together with the electrodes 2a - 2e, form an electrode package in which the electrodes 2a - 2e are held together at a defined distance.

The electrode package protrudes into the pipe section 14.

Referring to 4 and 5 The alternative use of the electrolytic cell 1 for processing an electrolyte concentrate will be explained in more detail.

4 is a sectional view in which the pipe section 14 is cut open.

An insert part 30 is now inserted into the pipe section 14, which includes a bulge 31 into which the electrodes protrude.

Within the bulge 31 there is an outlet 32 through which the electrolyte enriched with chlorine or bromine flows into the main stream in the pipe section 14.

The insert part 30 therefore serves to reduce the passage cross section between the pipe section 14 and the space with the electrodes.

In this operating state, no significant amount of water now flows from the pipe section 14 into the space with the electrodes.

Rather, as shown in the longitudinal section 5 is shown, the electrolyte over the Electrolyte input 17 is introduced into the space 13 with the electrodes 2.

The electrolyte flows through the package with the electrodes 2 and the water enriched with free chlorine or bromine flows via the outlet 32 into the main stream in the pipe section 14.

As here, together with the insert 30, the electrolytic cell 1 can be used in particular if the concentrate from a salt separation system (not shown) is to be introduced directly into the electrolytic cell via the electrolyte inlet 17.

The creation of a vortex that washes around the electrodes 2 is not necessary in this operating state, since the salt concentration is higher than in 1 until 3 operating state shown.

The invention made it possible to provide an electrolysis cell which has high efficiency and can be used flexibly, in particular for the production of free chlorine or bromine for swimming pool disinfection.

Reference symbol list

1

Electrolytic cell

2

electrode

3a, 3b

electrical Connection

10

Housing

11

Lid

12

web

13

Space

14

piece of pipe

15

Entrance

16

Exit

17

Electrolyte input

20

holder

21

finger

22

Spacers

30

Insert part

31

Bulging

32

Exit

Claims (9)

Electrolysis cell, comprising an input and an output and a housing with a plurality of plate-shaped electrodes, the housing with the plate-shaped electrodes providing an annular space into which electrolyte can be introduced from the input in such a way that a rotating flow is created by entering the annular space A vortex is created that flows past the plate-shaped electrodes. Electrolysis cell according to the preceding claim, characterized in that the space is circular cylindrical. Electrolysis cell according to one of the preceding claims, characterized in that the electrolysis cell is designed such that the electrolyte flows tangentially or secantially into the space. Electrolysis cell according to one of the preceding claims, characterized in that the electrodes protrude from the room into an input current. Electrolysis cell according to one of the preceding claims, characterized in that the electrolysis cell comprises an electrode pack with a plurality of stacked electrodes, in particular 5 to 10 electrodes. Electrolysis cell according to the preceding claim, characterized in that inner electrodes of the electrode pack are arranged as bipolar electrodes. Electrolysis cell according to one of the preceding claims, characterized in that the electrodes sit in holders which are stacked in the space of the housing. Electrolysis cell according to one of the preceding claims, characterized in that the electrodes are polygonal, in particular hexagonal. Use of an electrolytic cell according to one of the preceding claims for producing an oxidizing agent, in particular free chlorine, for swimming pool disinfection.

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