KR102572460B1 - Filter for water treatment apparatus - Google Patents

Abstract

The present invention relates to a filter for a water treatment device. In one aspect, the present invention provides a filter for a water treatment device, comprising: a chamber including an inlet and a water outlet; an electrode assembly positioned in the chamber to contact inflow water introduced through the inlet unit and including a plurality of electrode units; a first power connection unit including a first connection unit and a second connection unit that supply power to one side of the electrode assembly and are divided to supply different voltages; a second power connector supplying power to the other side of the electrode assembly; and a hydrophobic separator positioned between two electrode units in which a power connection state is changed by being positioned between the first connection part and the second connection part.

Description

Filter for water treatment apparatus {Filter for water treatment apparatus}

The present invention relates to a filter for a water treatment device.

In general, a water treatment device for generating purified water by treating raw water, such as a water purifier, has been disclosed in various modern forms. However, among methods applied to water treatment devices, methods that have recently been spotlighted are deionization methods such as EDI (Electro Deionization), CEDI (Continuous Electro Deionization), and CDI (Capacitive Deionization). Among them, the CDI-type water treatment device has recently been in the limelight.

The CDI method refers to a method of removing ions (contaminants) in water using the principle that ions are adsorbed and desorbed from the surface of an electrode by electric power.

When treated water containing ions is passed between the electrodes (anode and cathode) while voltage is applied to the electrodes, negative ions move to the positive electrode and positive ions move to the negative electrode. That is, adsorption takes place. Ions in the treated water can be removed by such adsorption.

However, such adsorption continues, and the electrode reaches a state where it can no longer adsorb ions. When this state is reached, the electrode is regenerated by separating the ions adsorbed on the electrode. At this time, washing water containing ions separated from the electrode is discharged to the outside. Such regeneration can be achieved by not applying a voltage to the electrodes, or by applying a voltage opposite to that of adsorption.

In the desalination of the CDI method equipped with an ion exchange membrane, the removal performance may vary depending on the electrode area. When the electrode area is increased, the removal performance may be improved, but the power consumed may increase accordingly.

In order to suppress water decomposition and side reactions, the voltage applied per electrode may be required to be maintained below a certain level (applied voltage 1.5 V, theoretical voltage 1.23 V). In general, as the area of the capacitive desalination of the ion exchange membrane in parallel structure increases, the current consumption value increases as the area increases, which may cause difficulties in manufacturing a circuit board (PCB).

Therefore, according to an embodiment of the present invention, the voltage per electrode can be kept constant using the improved series-parallel electrode assembly structure as described above, and performance degradation due to the series structure can be minimized.

In this way, it is advantageous to maintain the applied voltage of 1.5 V (theoretical voltage of 1.23 V) or less per electrode. In order to increase the TDS (total dissolved solid) removal rate, increasing the electrode area is the most representative method, and the current can increase as the electrode area increases. Then, when designing the PCB, a low voltage (1.5 V) high current structure is created, and improvement is required.

The present invention is to solve the above problems, and to provide a filter for a water treatment device capable of providing an optimal electrode structure in a serial and parallel structure of a water treatment device (CDI module) structure using an ion exchange membrane.

In addition, it is intended to provide a filter for a water treatment device capable of reducing the overall thickness of the electrode stack of the water treatment device.

In addition, it is intended to provide a filter for a water treatment device capable of minimizing passage of water in a conversion unit where series and parallel are switched, and maintaining or improving TDS removal performance.

The present invention is to achieve the above object, and can provide an optimal electrode structure in a serial and parallel structure of a water treatment device (CDI module) structure using an ion exchange membrane.

As the distance between the plus (+) electrode and the minus (-) electrode is shorter, the loss of voltage may be reduced.

In the case of a CDI module using such an ion exchange membrane, the distance between electrodes may increase as an ion exchange membrane having a certain thickness (for example, 40 μm) is added. This increased distance appears as a voltage drop, and when this is changed to a series/parallel structure, the TDS removal rate reduction due to the voltage drop may increase. This reduced voltage may reduce the overall TDS rejection rate.

Therefore, in order to minimize the voltage drop, according to an embodiment of the present invention, the voltage drop can be minimized by using a hydrophobic separator and inserting it into a position (switching unit) where the serial/parallel structure is switched.

As a specific aspect for this, the present invention is a filter for a water treatment device, comprising: a chamber including an inlet and a water outlet; an electrode assembly positioned in the chamber to contact inflow water introduced through the inlet unit and including a plurality of electrode units; a first power connection unit including a first connection unit and a second connection unit that supply power to one side of the electrode assembly and are divided to supply different voltages; a second power connector supplying power to the other side of the electrode assembly; and a hydrophobic separator positioned between two electrode units in which a power connection state is changed by being positioned between the first connection part and the second connection part.

In addition, the hydrophobic membrane can prevent water located on both sides of the hydrophobic membrane from permeating.

In addition, the hydrophobic membrane can prevent a reaction between cations and anions.

In addition, the hydrophobic membrane may prevent generation of at least one of Ca(OH) ₂ , CaCO ₃ , and MgCO ₃ .

In addition, the hydrophobic separator may have a thickness of 10 to 20 μm.

In addition, the electrode unit may include a plate-shaped electrode; and an ion exchange membrane filtering ions contained in the influent.

In addition, the electrode, the current collector; and an activated carbon coating layer positioned on at least one surface of the current collector.

In addition, the two electrode units to which the power connection state is changed may not have the ion exchange membrane on the surface facing the hydrophobic separation membrane.

In addition, the hydrophobic separator may include a first hydrophobic separator close to one electrode of the two electrode units; and a second hydrophobic separator close to the other electrode of the two electrode units.

In addition, a separation electrode unit may be positioned between the first hydrophobic separation membrane and the second hydrophobic separation membrane.

In addition, a first voltage may be supplied to the first connection part, a second voltage may be supplied to the second connection part, and a third voltage having a value between the first voltage and the second voltage may be supplied to the second power connection part. .

In another aspect, the present invention provides a filter for a water treatment device, comprising: a chamber including an inlet and a water outlet; an electrode assembly positioned in the chamber to contact inflow water introduced through the inlet unit and including a first electrode unit, a second electrode unit, and a spacer disposed between the first electrode unit and the second electrode unit; a power connection unit supplying power to the electrode assembly and including a series connection unit and a parallel connection unit; a switching unit positioned between the parallel connection units and converting a potential direction; And it may be configured to include a hydrophobic separation membrane located in the conversion unit.

In addition, the parallel connection unit may include a first connection unit and a second connection unit to which different voltages are supplied.

In addition, a first voltage may be supplied to the first connection part, a second voltage may be supplied to the second connection part, and a third voltage having a value between the first voltage and the second voltage may be supplied to the series connection part.

In addition, the ion exchange unit may not be located in the conversion unit.

According to an embodiment of the present invention, an optimal electrode structure can be provided in a serial and parallel structure of a water treatment device (CDI module) structure using an ion exchange membrane.

Through this, the ion exchange membrane and the spacer are removed from the conversion unit, and the overall thickness of the electrode stack of the water treatment device can be reduced.

In addition, it is possible to minimize the passage of water in a switching unit where series and parallel are switched, and maintain or improve TDS removal performance.

Furthermore, according to another embodiment of the present invention, there are additional technical effects not mentioned herein. A person skilled in the art can understand the entire meaning of the specification and drawings.

1 is a partially cut-away perspective view showing a filter for a water treatment device according to an embodiment of the present invention.
2 is a cross-sectional view showing a first electrode unit of a filter for a water treatment device according to an embodiment of the present invention.
3 is a cross-sectional view showing a second electrode unit of a filter for a water treatment device according to an embodiment of the present invention.
4 is a conceptual diagram illustrating a state in which water is purified in a filter for a water treatment device according to an embodiment of the present invention.
5 is a conceptual diagram illustrating a state in which a filter for a water treatment device according to an embodiment of the present invention is regenerated.
6 is a schematic cross-sectional view showing a stack structure of a filter for a water treatment device according to an embodiment of the present invention.
7 is a schematic cross-sectional view showing a switching unit of a filter for a water treatment device according to an embodiment of the present invention.
8 is a schematic cross-sectional view showing a stack structure of a filter for a water treatment device according to another embodiment of the present invention.
9 is a schematic cross-sectional view showing a switching unit of a filter for a water treatment device according to another embodiment of the present invention.
10 is a schematic cross-sectional view showing a stack structure of a filter for a water treatment device according to a comparative example of the present invention.
11 is a schematic cross-sectional view showing a switching unit of a filter for a water treatment device according to a comparative example of the present invention.
12 is a performance evaluation graph of a filter for a water treatment device according to an embodiment of the present invention.

Hereinafter, the embodiments disclosed in this specification will be described in detail with reference to the accompanying drawings, but the same or similar elements are given the same reference numerals regardless of reference numerals, and redundant description thereof will be omitted. The suffixes "module" and "unit" for components used in the following description are given or used together in consideration of ease of writing the specification, and do not have meanings or roles that are distinct from each other by themselves. In addition, in describing the embodiments disclosed in this specification, if it is determined that a detailed description of related known technologies may obscure the gist of the embodiments disclosed in this specification, the detailed description will be omitted. In addition, it should be noted that the accompanying drawings are only for easy understanding of the embodiments disclosed in this specification, and should not be construed as limiting the technical idea disclosed in this specification by the accompanying drawings.

Furthermore, although each drawing is described for convenience of explanation, it is also within the scope of the present invention for those skilled in the art to implement another embodiment by combining at least two or more drawings.

It is also to be understood that when an element such as a layer, region or substrate is referred to as being “on” another element, it may be directly on the other element or intervening elements may exist therebetween. There will be.

A water treatment device according to an embodiment of the present invention may correspond to various water purification devices such as a water purifier and a water softener. In addition, the water treatment device according to the present invention may correspond to a water purification means installed in a washing machine, a dishwasher, a refrigerator, or the like.

In the water treatment device according to an embodiment of the present invention, various embodiments may occur in a process of electrosorbing ions and hardness substances included in raw water introduced from the outside and then discharging them.

Hereinafter, a filter for a water treatment device according to an embodiment of the present invention will be described.

1 is a partially cut-away perspective view showing a filter for a water treatment device according to an embodiment of the present invention. 1 shows a filter for a water treatment device of a deionization method such as CDI (Capacitive Deionization). A filter for such a water treatment device may be referred to as a CDI module.

Referring to FIG. 1 , a filter for a water treatment device includes a chamber 100 including an inlet 110 into which water is introduced and a water outlet 120 through which water is discharged. In FIG. 1 , an internal view of the chamber 100 is shown with a part cut away.

An electrode assembly 200 including a plurality of electrode units 210 and 220 (see FIGS. 3 and 4) may be provided in the chamber 100 so as to be in contact with the inflow water introduced through the water inlet 110. .

A power connector 250 for supplying power may be connected to the electrode assembly 200 . One side of the electrode of the electrode assembly 200 protrudes from one side of the electrode assembly 200 and can be connected to each other through the power connection part 250 .

In this way, the electrode assembly 200 is accommodated in the inner space of the chamber 100, and water (inflow water) may flow into the inner space of the chamber 100 from the outside through the water inlet 110.

At this time, the introduced water may pass through the electrode assembly 200 and then be discharged to the outside of the chamber 100 through the water outlet 120 . In this process, ions included in water may be adsorbed to and removed from the electrode assembly 200 while passing through the electrode assembly 200 .

The chamber 100 may be formed in a rectangular parallelepiped shape, and may be divided into an upper part 101 and a lower part 102 and provided. This chamber 100 may be provided so as not to leak water. To this end, an upper plate 103, a lower plate 104, a fastening means 130 such as a bolt binding the upper plate 103 and the lower plate 104, and a sealing member positioned between them may be provided.

In this way, when the chamber 100 is separated into the upper part 101 and the lower part 102, the inner space of the chamber 100 is exposed to the outside, and the work of stacking the electrode assembly 200 in the inner space is easy. can proceed

In addition, when a problem occurs in the chamber 100, the upper part 101 and the lower part 102 are separated so that inspection and maintenance can be easily performed.

Inlet water supplied into the chamber 100 through the inlet 110 may be supplied to the side of the electrode assembly 200 . In this process, the inflow water may be evenly supplied to the entire thickness of the electrode assembly 200 .

In this way, after water is evenly supplied in the lateral direction of the electrode assembly 200, ion exchange can be performed while flowing from the lateral direction of the electrode assembly 200 toward the center. Thereafter, the ion-exchanged water may escape to the outside through the water outlet 120 connected to the inside of the electrode assembly 200, for example, to the center.

2 is a cross-sectional view showing a first electrode unit of a filter for a water treatment device according to an embodiment of the present invention. 3 is a cross-sectional view showing a second electrode unit of a filter for a water treatment device according to an embodiment of the present invention.

The electrode assembly 200 includes a first electrode unit 210, a second electrode unit 220, and a spacer 230 positioned between the first electrode unit 210 and the second electrode unit 220 (see FIG. 4 below). can include

The electrode assembly 200 may be provided by stacking a plurality of first electrode units 210 , second electrode units 220 , and spacers 230 .

Here, the first electrode unit 210 may include a dust collector 211 and an activated carbon coating layer 212 positioned on at least one side of the dust collector 211 . These activated carbon coating layers 212 may be located on both sides of the dust collector 211 . However, in some cases, the activated carbon coating layer 212 may be located only on one side of the dust collector 211 .

The dust collector 211 and the activated carbon coating layer 212 positioned on at least one side of the dust collector 211 may be referred to as a first electrode. These first electrodes 211 and 212 may be negative electrodes.

In addition, a part of the dust collecting body 211 may be extended or a conductor may be connected to the dust collecting body 211 so that the electrode unit 214 may be provided. Power connection units 250 and 260 may be connected to the electrode unit 214 .

At this time, the cation exchange membrane 213 may be positioned outside the first electrodes 211 and 212, that is, on the activated carbon coating layer 212. At this time, the cation exchange membrane 213 may be located on both sides of the activated carbon coating layer 212 . However, in some cases, the cation exchange membrane 213 may be located on only one side of the activated carbon coating layer 212 .

Depending on the configuration of the power connectors 250 and 260, the plurality of electrode units 210 and 220 may have a serial and parallel structure in which serial and parallel connections are mixed.

At this time, the cation exchange membrane 213 may be located only on one side of the activated carbon coating layer 212 between the two electrode units where the power connection state is changed, that is, in the so-called conversion unit where the electric potential direction is switched. Also, in some cases, the cation exchange membrane 213 may not be provided on the activated carbon coating layer 212 .

Similarly, the second electrode unit 220 may include a dust collector 221 and an activated carbon coating layer 222 positioned on at least one side of the dust collector 221 . The activated carbon coating layer 222 may be located on both sides of the dust collector 221 . However, in some cases, the activated carbon coating layer 222 may be located only on one side of the dust collector 221 .

The dust collector 221 and the activated carbon coating layer 222 positioned on at least one side of the dust collector 221 may be referred to as a second electrode. These second electrodes 221 and 222 may be positive electrodes.

In addition, a part of the dust collecting body 221 may be extended or a conductor may be connected to the dust collecting body 221 so that the electrode part 224 may be provided. Power connection units 250 and 260 may be connected to the electrode unit 224 .

At this time, the anion exchange membrane 223 may be positioned outside the second electrodes 221 and 222, that is, on the activated carbon coating layer 222. At this time, the anion exchange membrane 223 may be located on both sides of the activated carbon coating layer 222 . However, in some cases, the anion exchange membrane 223 may be located on only one side of the activated carbon coating layer 222 .

Depending on the configuration of the power connectors 250 and 260, the plurality of electrode units 210 and 220 may have a serial and parallel structure in which serial and parallel connections are mixed.

At this time, the anion exchange membrane 223 may be located only on one side of the activated carbon coating layer 222 between the two electrode units where the power connection state is changed, that is, in the so-called conversion unit where the electric potential direction is switched. Also, in some cases, the anion exchange membrane 223 may not be provided on the activated carbon coating layer 222 .

4 is a conceptual diagram showing a state in which water is purified in a filter for a water treatment device according to an embodiment of the present invention, and FIG. 5 is a conceptual diagram showing a state in which a filter for a water treatment device according to an embodiment of the present invention is regenerated. am. Hereinafter, with reference to FIGS. 4 and 5, an operation of a filter for a water treatment device according to an embodiment of the present invention will be described.

This operation may be performed in a state in which the first electrode unit 210 and the second electrode unit 220 receive power from the power supply unit 300 through the first power connection unit 250 and the second connection unit 260, respectively. .

As mentioned above, depending on the configuration of the power connectors 250 and 260, the plurality of electrode units 210 and 220 may have a serial and parallel structure in which serial and parallel connections are mixed. This will be described later in detail with reference to the drawings. Here, the operation of the filter (CDI module) for the water treatment device will be described. In addition, the configuration of the cation exchange membrane or anion exchange membrane is omitted from description.

First, referring to FIG. 4 , the electrode unit 220 disposed on the left side of the drawing is positively charged, and the electrode unit (eg, the first electrode unit 210) disposed on the right side of the drawing is charged negatively. In, when the influent is passed between the two electrode units 210 and 220, the negative ions (-) included in the influent are adsorbed to the positively charged electrode unit 220 on the left side, and the positive ions (+) included in the influent are negatively charged. It can be adsorbed to the electrode unit 210 on the right side that is charged with .

Through this process, anions (-) and cations (+) included in the influent are adsorbed and removed, and the influent can be purified.

Conversely, when the inflow water passes between the two electrode units 210 and 220 in a state where the electrode unit 210 disposed on the right side of the drawing is positively charged and the electrode unit 220 disposed on the left side of the drawing is charged negatively, , Negative ions (-) included in the influent may be adsorbed to the positively charged electrode unit 210 on the right side, and positive ions (+) included in the influent water may be adsorbed to the negatively charged electrode unit 220 on the left side. .

At this time, the inflow water can easily pass between the two electrode units 210 and 220 through the permeable spacer 230 disposed to prevent a short circuit and secure a passage between the two electrode units 210 and 220 .

However, as this adsorption continues and the number of ions adsorbed to the electrode units 210 and 220 increases, the electrode units 210 and 220 may no longer adsorb ions or may reach a state in which the ion adsorption capacity is significantly reduced. there is.

In this state, as shown in FIG. 5 , it is necessary to regenerate the electrode units 210 and 220 by separating ions adsorbed on the electrode units 210 and 220 .

In this way, as a method for regenerating the electrode units 210 and 220, there is a method of cutting off the current supply and a method of flowing the current opposite to the case of adsorbing ions.

In the case of the embodiment of the present invention, when inflow water (treated water) is supplied to the electrode assembly 200, the power supply unit 300 supplies current in one direction and adsorbs ions to the electrode units 210 and 220 to absorb ions in the water. can be removed.

In addition, when inflow water (washing water) is supplied to the electrode assembly 200, the power supply unit 300 supplies current in a direction opposite to the above one direction, and discharges ions adsorbed to the electrode units 210 and 220 into the water. The electrode units 210 and 220 may be regenerated.

For example, as shown in FIG. 4, negative ions (-) included in the raw water are adsorbed to the positively charged electrode unit 220 on the left side, and positive ions (+) included in the raw water are negatively charged electrode units on the right side. In order to regenerate the electrode units 210 and 220 in the state adsorbed to 210, the electrode unit 220 on the left side of the drawing is charged as a cathode as shown in FIG. 5 by changing the current flow, and the electrode on the right side of the drawing is charged. Unit 210 can be positively charged.

Then, the negative ions (-) adsorbed to the left electrode unit 220 during the water purification process are separated from the negatively charged left electrode unit 220, and the positive ions (-) adsorbed to the right electrode unit 210 during the water purification process ( +) can be separated from the positively charged electrode unit 210 on the right.

In this process, positive ions (+) and negative ions (-) separated from the electrode units 210 and 220 on both sides may be discharged to the outside together with the washing water.

When the ions adsorbed on the electrode units 210 and 220 are removed through the cleaning process of the electrode units 210 and 220, the ion removal ability of the electrode assembly 200 is regenerated, and the ion removal ability is maintained constant. can

When the electrode assembly 200 is driven in this way, since ions in the water are quickly removed, the hardness of the water is lowered and the water can be softened.

6 is a schematic cross-sectional view showing a stack structure of a filter for a water treatment device according to an embodiment of the present invention. 7 is a schematic cross-sectional view showing a switching unit of a filter for a water treatment device according to an embodiment of the present invention.

6 schematically shows an electrode assembly of a filter for a water treatment device according to an embodiment of the present invention.

As described above, the electrode assembly 200 is positioned in the chamber 100 to contact inflow water introduced through the water acquisition unit 110 and may include a plurality of electrode units 210 and 220 .

The electrode assembly 200 may be provided by stacking a plurality of first electrode units 210 and second electrode units 220 with spacers 230 interposed therebetween.

In addition, the activated carbon coating layers 212 and 222 in each of the electrode units 210 and 220 are omitted. That is, in FIG. 6, each of the electrode units 210 and 220 is shown in a state where the cation exchange membrane 213 and the anion exchange membrane 223 are positioned on the collectors 211 and 221.

Referring to the upper portion (a) of FIG. 6 , the first electrode unit 210 has electrode units 214 disposed in one direction, and the second electrode unit 220 has electrode units 224 disposed in the other direction. It can be. For example, the electrode part 214 of the first electrode unit 210 is provided on the left side and connected to the first power connection part 250, and the electrode part 224 of the second electrode unit 220 is provided on the right side It may be connected to the second power connection unit 260 .

The connection directions of each of the electrode units 210 and 220 may be reversed in the lower part (b) of FIG. 6 . In addition, the first power connection unit 250 includes a first connection unit 251 (upper side) and a second connection unit 252 (lower side) to which different voltages are supplied to supply power to one side of the electrode assembly 200. there is. Also, the second power connector 260 may be located on the opposite side of the first power connector 250 to supply power to the other side of the electrode assembly 200 .

With this configuration, in the electrode assembly 200, the connection direction of the power source can be switched at a portion between the upper side part (a) and the lower side part (b) (hereinafter, referred to as the switching part (A)). Accordingly, the electrode assembly 200 may have a series-parallel connection configuration in which a series connection configuration and a parallel connection configuration are mixed.

At this time, power having a voltage between the first connection part 251 and the second connection part 252 of the first power connection part 250 may be supplied to the second power connection part 260 . For example, as shown in FIG. 6 , power of 3 V voltage may be connected through the first connection part 251 and power of 0 V voltage may be connected through the second connection part 252 . In addition, power of 1.5 V may be supplied to the second power connection unit 260 .

Therefore, in the upper portion (a) of FIG. 6, as shown, the left side has a positive (+) potential and the right side has a negative (-) potential, and in the lower portion (b), the left side has a negative (-) potential. With , the right side can have a positive (+) potential.

At this time, the hydrophobic separator 240 located between the first connection unit 251 and the second connection unit 252 and located between the two electrode units 210a and 220a (ie, the switching unit A) where the power connection state is changed. ) may be provided.

The hydrophobic membrane 240 can prevent water located on both sides of the hydrophobic membrane 240 from permeating. That is, the hydrophobic membrane 240 can prevent water located on one side of the hydrophobic membrane 240 from permeating to the other side under a certain water pressure.

The material of the hydrophobic separator 240 may be a polyethylene (PE) or polypropylene (PP)-based material.

The hydrophobic membrane 240 may include a material that prevents ions in water from participating in the reaction even when power is supplied through the power supply unit 250 . That is, the hydrophobic membrane 240 has resistance to water and may be made of a material that does not pass water under a certain water pressure. For example, the water resistance characteristic of the hydrophobic membrane 240 may be maintained even at a water pressure of 10 kgf or less.

The spacer 230 positioned between the electrode units 210 and 220 may have hydrophilicity opposite to that of the hydrophobic separator 240 . That is, the spacer 230 may have a structure through which water passes. For example, the spacer 230 includes many holes in the form of a mesh, so that water can pass through the spacer 230 . Conversely, the hydrophobic separator 240 may have a sheet-like structure rather than a mesh-like structure.

The hydrophobic separator 240 may be advantageous as it is thinner in a range in which a short circuit does not occur between the electrode units 210 and 220 . That is, due to the characteristics of the CDI-type electrode assembly 200, the hydrophobic separator 240 is made of a polyethylene (PE) or polypropylene (PP)-based material to prevent short circuits and leakage at the same time. It may advantageously be formed to a thickness of approximately 10 μm or greater. For example, considering the electrode stack structure of the electrode assembly 200, the hydrophobic separator 240 may have a thickness of 20 μm or less. That is, the hydrophobic separator 240 may have a thickness of 10 to 20 μm.

In addition, the hydrophobic separator 240 may prevent a reaction between cations and anions. For example, the hydrophobic membrane 240 may prevent generation of at least one of Ca(OH) ₂ , CaCO ₃ , and MgCO ₃ .

Referring to FIGS. 6 and 7 , the two electrode units 210a and 220a located in the so-called switching unit A where the power connection state is changed may not have the ion exchange membranes 213 and 223 .

For example, the ion exchange membranes 213 and 223 described above may not be provided on the surface facing the hydrophobic separation membrane 240 in the conversion unit A. That is, in the conversion unit (A), the first electrode unit 210a may be provided with only the dust collection layer 211 and the activated carbon coating layer 212 . In addition, in the conversion unit (A), the second electrode unit 220a may be provided with only the dust collection layer 221 and the activated carbon coating layer 222 .

Accordingly, in the conversion unit A, the first electrode unit 210a may directly contact the hydrophobic separator 240 and the second electrode unit 220a may directly contact the hydrophobic separator 240 .

The cation exchange membrane 213 can pass only cations and the anion exchange membrane 223 can pass only anions. Therefore, the anion exchange membrane 223 can improve overall performance within the CDI module. In addition, the anion exchange membrane 223 can prevent a reaction between the cation material and the anion material at the electrode.

Since the cation exchange membrane 213 and the anion exchange membrane 223 do not exist in the portion where the hydrophobic membrane 240 is located, if water permeates, the performance of the CDI module may be reduced. Therefore, it may be advantageous that the above-described ion exchange membranes 213 and 223 are not provided on the surface facing the hydrophobic separation membrane 240 in the conversion unit A.

Accordingly, a reaction formed by meeting cations and anions (typically CCa(OH) ₂ , CaCO ₃ , and MgCO ₃ ) can be minimized.

In addition, in the case of operating at a reverse voltage (-1.5 V) during ion desorption, ion desorption can be performed smoothly when the ion exchange membranes 213 and 223 are present. Therefore, in the case where the ion exchange membranes 213 and 223 are present in parts other than the conversion part A, the performance of the CDI module can be maintained for a long time.

According to this structure, a voltage of 1.5 V may be applied between the first electrode unit 210a and the second electrode unit 220a located in the switching unit A, and substantially the first electrode unit 210a A potential difference of 1.5 V or less may be formed between the second electrode unit 220a and the second electrode unit 220a.

At this time, water may not pass between the first electrode unit 210a and the hydrophobic separator 240 and between the second electrode unit 220a and the hydrophobic separator 240 located in the conversion unit A.

8 is a schematic cross-sectional view showing a stack structure of a filter for a water treatment device according to another embodiment of the present invention. 9 is a schematic cross-sectional view showing a switching unit of a filter for a water treatment device according to another embodiment of the present invention.

8 schematically shows an electrode assembly of a filter for a water treatment device according to an embodiment of the present invention.

As described above, the electrode assembly 200 is positioned in the chamber 100 to contact inflow water introduced through the water acquisition unit 110 and may include a plurality of electrode units 210 and 220 .

The electrode assembly 200 may be provided by stacking a plurality of first electrode units 210 and second electrode units 220 with spacers 230 interposed therebetween.

In addition, the activated carbon coating layers 212 and 222 in each of the electrode units 210 and 220 are omitted. That is, in FIG. 8, each of the electrode units 210 and 220 is shown in a state where the cation exchange membrane 213 and the anion exchange membrane 223 are positioned on the collectors 211 and 221.

Referring to the upper portion (a) of FIG. 8 , the first electrode unit 210 has electrode units 214 disposed in one direction, and the second electrode unit 220 has electrode units 224 disposed in the other direction. It can be. For example, the electrode part 214 of the first electrode unit 210 is provided on the left side and connected to the first power connection part 250, and the electrode part 224 of the second electrode unit 220 is provided on the right side It may be connected to the second power connection unit 260 .

The connection directions of each of the electrode units 210 and 220 may be reversed in the lower part (b) of FIG. 8 . In addition, the first power connection unit 250 includes a first connection unit 251 (upper side) and a second connection unit 252 (lower side) to which different voltages are supplied to supply power to one side of the electrode assembly 200. there is. Also, the second power connector 260 may be located on the opposite side of the first power connector 250 to supply power to the other side of the electrode assembly 200 .

With this configuration, in the electrode assembly 200, the connection direction of the power source can be switched at a portion between the upper portion (a) and the lower portion (b) (hereinafter, referred to as the switching portion (B)). Accordingly, the electrode assembly 200 may have a series-parallel connection configuration in which a series connection configuration and a parallel connection configuration are mixed.

At this time, power having a voltage between the first connection part 251 and the second connection part 252 of the first power connection part 250 may be supplied to the second power connection part 260 . For example, as shown in FIG. 8 , power of 3 V voltage may be connected through the first connection part 251 and power of 0 V voltage may be connected through the second connection part 252 . In addition, power of 1.5 V may be supplied to the second power connection unit 260 .

Therefore, in the upper portion (a) of FIG. 8, as shown, the left side has a positive (+) potential and the right side has a negative (-) potential, and in the lower portion (b), the left side has a negative (-) potential. With , the right side can have a positive (+) potential.

At this time, the hydrophobic separator 241 located between the first connection unit 251 and the second connection unit 252 and located between the two electrode units 210b and 220b (ie, the switching unit B) where the power connection state is changed. , 242) may be provided.

That is, in the switching part (B), the first hydrophobic separator 241 of the two electrode units 210b and 220b close to one electrode 210b and the second of the two electrode units 210b and 220b close to the other electrode 220b A hydrophobic separator 242 may be included.

In addition, a separation electrode unit 270 may be positioned between the first hydrophobic separation membrane 241 and the second hydrophobic separation membrane 242 .

These hydrophobic membranes 241 and 242 can prevent water located on both sides of the hydrophobic membranes 241 and 242 from permeating. That is, the hydrophobic membranes 241 and 242 may prevent water located on one side of the hydrophobic membranes 241 and 242 from permeating to the other side under a certain water pressure.

As the material of the hydrophobic membranes 241 and 242, polyethylene (PE) or polypropylene (PP)-based materials may be suitable.

The characteristics of the hydrophobic membranes 241 and 242 may be the same as those of the hydrophobic membrane 240 described above. Therefore, overlapping descriptions will be omitted below.

Referring to FIGS. 8 and 9 , the two electrode units 210b and 220b located in the so-called switching unit B where the power connection state is changed may not have the ion exchange membranes 213 and 223 .

For example, the above-described ion exchange membranes 213 and 223 may not be provided on surfaces facing the hydrophobic separation membranes 241 and 242 in the conversion unit B, respectively. That is, in the conversion unit (B), the first electrode unit 210b may be provided with only the dust collecting layer 211 and the activated carbon coating layer 212 . In addition, in the conversion unit (B), the second electrode unit 220b may be provided with only the dust collection layer 221 and the activated carbon coating layer 222 . Meanwhile, the separation electrode unit 270 in the conversion unit B may include a dust collecting layer 271 and an activated carbon coating layer 272 positioned on both sides of the dust collecting layer 271.

Therefore, in the conversion unit (B), the first electrode unit 210b may directly contact the first hydrophobic separator 241 and the second electrode unit 220b may directly contact the second hydrophobic separator 242. can Also, both surfaces of the separation electrode unit 270 may directly contact the first hydrophobic separation membrane 241 and the second hydrophobic separation membrane 242 .

The cation exchange membrane 213 can pass only cations and the anion exchange membrane 223 can pass only anions. Therefore, the anion exchange membrane 223 can improve overall performance within the CDI module. In addition, the anion exchange membrane 223 can prevent a reaction between the cation material and the anion material at the electrode.

Since the cation exchange membrane 213 and the anion exchange membrane 223 do not exist in the portion where the hydrophobic separation membranes 241 and 242 are located, if water permeates, the performance of the CDI module may decrease. Therefore, it may be advantageous that the above-described ion exchange membranes 213 and 223 are not provided on the surface facing the hydrophobic separation membranes 241 and 242 in the conversion unit B.

Accordingly, a reaction formed by meeting cations and anions (typically CCa(OH) ₂ , CaCO ₃ , and MgCO ₃ ) can be minimized.

In addition, in the case of operating at a reverse voltage (-1.5 V) during ion desorption, ion desorption can be performed smoothly when the ion exchange membranes 213 and 223 are present. Therefore, in the case where the ion exchange membranes 213 and 223 are present in parts other than the conversion part B, the performance of the CDI module can be maintained for a long time.

According to this structure, a 3 V voltage may be applied between the first electrode unit 210b and the second electrode unit 220b located in the switching unit B, and substantially the first electrode unit 210b A potential difference of 1.5 V or less may be formed between the electrode unit 270 and the separation electrode unit 270 and between the separation electrode unit 270 and the second electrode unit 220a.

At this time, between the first electrode unit 210a and the first hydrophobic separator 241 located in the conversion unit B, the second electrode unit 220a, the second hydrophobic separator 242, and the first hydrophobic separator 241 Water may not pass between the second hydrophobic separator 242 and the separation electrode unit 270 and between the separation electrode unit 270 and the separation electrode unit 270 .

10 is a schematic cross-sectional view showing a stack structure of a filter for a water treatment device according to a comparative example of the present invention. 11 is a schematic cross-sectional view showing a switching unit of a filter for a water treatment device according to a comparative example of the present invention.

10 schematically shows an electrode assembly of a filter for a water treatment device according to a comparative example of the present invention.

The electrode assembly 200 may include a plurality of electrode units 21 and 22 .

Such an electrode assembly may be provided by stacking a plurality of first electrode units 21 and second electrode units 22 with spacers 23 interposed therebetween.

In addition, the activated carbon coating layers 212 and 222 in each of the electrode units 21 and 22 are omitted. That is, in FIG. 10, each of the electrode units 21 and 22 is shown in a state where a cation exchange membrane and an anion exchange membrane are respectively positioned on the collector.

Referring to the upper portion of FIG. 10 , the first electrode unit 21 may have electrode units disposed in one direction, and the second electrode unit 22 may have electrode units disposed in the other direction.

The connection directions of each of the electrode units 21 and 22 may be reversed in the lower portion of FIG. 10 . In addition, the first power connection unit 25 includes a first connection unit 25a (upper side) and a second connection unit 25b (lower side) to which different voltages are supplied to supply power to one side of the electrode assembly. And, the second power connection unit 26 is located on the opposite side of the first power connection unit 25 to supply power to the other side of the electrode assembly.

With this configuration, the connection direction of the power supply can be switched in the portion between the upper and lower portions of the electrode assembly (hereinafter, referred to as the switching unit C). Accordingly, the electrode assembly may have a series-parallel connection configuration in which a series connection configuration and a parallel connection configuration are mixed.

At this time, power having a voltage between the first connection part 25a and the second connection part 25b of the first power connection part 25 may be supplied to the second power connection part 26 . For example, as shown in FIG. 10 , power of 3 V voltage may be connected through the first connection portion 25a and power of 0 V voltage may be connected through the second connection portion 25b. In addition, power of 1.5 V may be supplied to the second power connection unit 26 .

Therefore, in the upper part of FIG. 10, as shown, the left side has a positive (+) potential and the right side has a negative (-) potential, and in the lower side, the left side has a negative (-) potential and the right side has a positive (-) potential. +) potential.

On the other hand, a spacer is located between the first connection part 25a and the second connection part 25b and the same as the other parts between the two electrode units 21 and 22 (ie, the switching part C) where the power connection state is changed. (23) can be located.

The spacer 23 positioned between the electrodes 21 and 22 may have hydrophilicity. That is, the spacer 23 may have a structure through which water passes. For example, the spacer 23 includes many holes in the form of a mesh, so that water can pass through the spacer 23 .

In addition, the electrodes 21 and 22 located in the conversion unit C may also include a cation exchange unit and an anion exchange unit, respectively.

With this structure, a voltage of 1.5 V may be applied between the first electrode 21 and the second electrode 22 located in the switching unit C, and substantially between the first electrode 21 and the second electrode 21. A potential difference of 1.5 V or less may be formed between the electrodes 22 .

At this time, water may pass between the first electrode 21 and the spatter 23 and between the second electrode 22 and the spacer 23 located in the conversion unit C.

12 is a performance evaluation graph of a filter for a water treatment device according to an embodiment of the present invention.

A filter (CDI module) for a water treatment device using a deionization method such as capacitive deionization (CDI) may operate while adsorption and desorption of ions are repeated.

First, the operation principle of CDI will be briefly described as follows.

A large amount of scale-inducing substances (Ca ²⁺ , Mg ^{2+ ,} etc.) contained in the raw water flows into the filter for the water treatment device and is discharged to the rear end of the filter for the water treatment device through an adsorption process (adsorption operation) for a certain period of time. Thereafter, when the adsorption is saturated, the adsorbed ions may be discharged to the rear end of the filter for the water treatment device through a desorption process (desorption operation).

Therefore, the graph shown in FIG. 12 can be divided into an adsorption process located at 1 to 3 minutes, 6 minutes to 9 minutes, etc., and a desorption process located at 3 to 6 minutes, 9 minutes to 12 minutes, etc.

The vertical axis of the graph represents conductivity (uS/cm), and this half value usually means total dissolved solids (TDS) or TDS removal rate.

At this time, the adsorption process is an operation process in which a voltage of 1.5 V (or 3 V) is applied to the electrode to adsorb contaminants of passing water into the electrode.

On the other hand, the desorption process is an operation process in which contaminants adsorbed on the electrode are discharged by using a reverse voltage (-1.5 V) or a short-circuit state on the electrode.

The TDS removal rate is calculated as “1-(pure water TDS/raw water TDS))×100 (%)” and is one of the indicators representing the water purification performance of the CDI module. In FIG. 12 , a sawtooth waveform may be seen because the automatic electrode cleaning function operates periodically and the removal rate may temporarily increase.

Referring to FIG. 12, it can be seen that the TDS removal rate is superior in the case of applying the embodiment (Example 1) of the present invention compared to the case of the conventional and comparative examples.

The ion removal method of the CDI module having an ion exchange membrane, so-called ion exchange membrane capacitive desalination, may have different removal performance depending on the area of the electrode. When the electrode area is increased, the removal performance may be improved, but the power consumed may increase accordingly.

In order to suppress water decomposition and side reactions, the voltage applied per electrode may be required to be maintained below a certain level (applied voltage 1.5 V, theoretical voltage 1.23 V). In general, as the area of the capacitive desalination of the ion exchange membrane in parallel structure increases, the current consumption value increases as the area increases, which may cause difficulties in manufacturing a circuit board (PCB).

Therefore, according to an embodiment of the present invention, the voltage per electrode can be kept constant using the improved series-parallel electrode assembly structure as described above, and performance degradation due to the series structure can be minimized.

In this way, it is advantageous to maintain the applied voltage of 1.5 V (theoretical voltage of 1.23 V) or less per electrode. In order to increase the TDS removal rate, increasing the electrode area is the most representative method, and the current can increase as the electrode area increases. Then, when designing the PCB, a low voltage (1.5 V) high current structure is created and needs to be improved.

To this end, when a series-parallel structure as in the comparative example is applied, as shown in FIG. 12, a TDS removal rate may be reduced. In addition, an optimal series-parallel structure is required in the CDI module to which the ion exchange membrane is applied.

Referring to Table 1 below, it can be confirmed that the operating current is greatly reduced to 2.78A when the embodiment (Example 1) of the present invention is applied. It can be seen that the average removal rate at this time is 92.40%, which is relatively smaller than the parallel structure having a very large operating current, but greatly improved compared to the case of the comparative example.

As the distance between the plus (+) electrode and the minus (-) electrode is shorter, the loss of voltage may be reduced. In the embodiment described above, since the ion exchange membranes 213 and 223 are provided, electrode voltage may decrease.

In the case of a CDI module using such an ion exchange membrane, the distance between electrodes may increase as an ion exchange membrane having a certain thickness (for example, 40 μm) is added. This increased distance appears as a voltage drop, and when this is changed to a series/parallel structure, the TDS removal rate reduction due to the voltage drop may increase. This reduced voltage may reduce the overall TDS rejection rate.

Therefore, in order to minimize the voltage drop, according to an embodiment of the present invention, the voltage drop can be minimized by using a hydrophobic separator and inserting it into a position (switching unit) where the serial/parallel structure is switched.

In this way, according to an embodiment of the present invention, an optimal electrode structure can be provided in a series-parallel structure of a CDI module structure using an ion exchange membrane.

Through this, the ion exchange membrane and the spacer are removed from the conversion unit, thereby reducing the overall thickness.

In addition, the passage of water can be minimized by using a hydrophobic separation membrane provided in a conversion unit where serial and parallel conversion is performed, and TDS removal performance can be maintained or improved.

The above description is merely an example of the technical idea of the present invention, and various modifications and variations can be made to those skilled in the art without departing from the essential characteristics of the present invention.

Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments.

The protection scope of the present invention should be construed according to the claims below, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

100: chamber 200: electrode assembly
210: first electrode unit 220: second electrode unit
211, 221: dust collector 212, 222: activated carbon coating layer
213: cation exchange membrane 223: anion exchange membrane
214, 224: electrode part 240: hydrophobic separator
241: first hydrophobic separator 242: second hydrophobic separator
250, 260: power connection
251: first connection part 252: second connection part
270: separation electrode unit

Claims (20)

In the filter for a water treatment device,
a chamber including an inlet and outlet;
an electrode assembly positioned in the chamber to contact inflow water introduced through the inlet unit and including a plurality of electrode units;
a first power connection unit including a first connection unit and a second connection unit that supply power to one side of the electrode assembly and are divided to supply different voltages;
a second power connector supplying power to the other side of the electrode assembly; and
A filter for a water treatment device, characterized in that it comprises a hydrophobic separation membrane located between the two electrode units in which the power connection state is changed by being located between the first connection part and the second connection part. The filter for a water treatment device according to claim 1, wherein the hydrophobic separation membrane prevents water located on both sides of the hydrophobic separation membrane from permeating. The filter for a water treatment device according to claim 1, wherein the hydrophobic separation membrane prevents a reaction between cations and anions. The filter of claim 1, wherein the hydrophobic membrane prevents generation of at least one of Ca(OH) ₂ , CaCO ₃ , and MgCO ₃ . The filter for a water treatment device according to claim 1, wherein the hydrophobic membrane has a thickness of 10 to 20 μm. The method of claim 1, wherein the electrode unit,
plate-shaped electrodes; and
A filter for a water treatment device comprising an ion exchange membrane for filtering ions contained in the influent. The method of claim 6, wherein the electrode,
current collector; and
A filter for a water treatment device comprising an activated carbon coating layer located on at least one surface of the current collector. The filter for a water treatment device according to claim 6, wherein the two electrode units to which the power connection state is changed do not have the ion exchange membrane on the surface facing the hydrophobic separation membrane. The method of claim 1, wherein the hydrophobic separation membrane,
a first hydrophobic separator close to one electrode of the two electrode units; and
A filter for a water treatment device, characterized in that it comprises a second hydrophobic separation membrane close to the other electrode of the two electrode units. The filter for a water treatment device according to claim 9, wherein a separation electrode unit is positioned between the first hydrophobic separation membrane and the second hydrophobic separation membrane. The method of claim 1 , wherein a first voltage is supplied to the first connection part, a second voltage is supplied to the second connection part, and a third voltage between the first voltage and the second voltage is supplied to the second power connection part. A filter for a water treatment device, characterized in that supplied. In the filter for a water treatment device,
a chamber including an inlet and outlet;
an electrode assembly positioned in the chamber to contact inflow water introduced through the inlet unit and including a first electrode unit, a second electrode unit, and a spacer positioned between the first electrode unit and the second electrode unit;
a power connection unit supplying power to the electrode assembly and including a series connection unit and a parallel connection unit;
a conversion unit positioned between the parallel connection units and converting a potential direction; and
A filter for a water treatment device, characterized in that it comprises a hydrophobic separation membrane located in the conversion unit. The filter for a water treatment device according to claim 12, wherein the parallel connection part comprises a first connection part and a second connection part to which different voltages are supplied. The method of claim 13, wherein a first voltage is supplied to the first connection part, a second voltage is supplied to the second connection part, and a third voltage having a value between the first voltage and the second voltage is supplied to the series connection part. A filter for a water treatment device, characterized in that. The method of claim 12, wherein at least one electrode unit of the first electrode unit and the second electrode unit,
plate-shaped electrodes; and
A filter for a water treatment device comprising an ion exchange membrane for filtering ions contained in the influent. The filter for a water treatment device according to claim 15, wherein the ion exchange membrane is not located in the conversion unit. The method of claim 12, wherein the hydrophobic separation membrane,
a first hydrophobic separator close to one electrode of the two electrode units; and
A filter for a water treatment device, characterized in that it comprises a second hydrophobic separation membrane close to the other electrode of the two electrode units. The filter for a water treatment device according to claim 17, wherein a separation electrode unit is positioned between the first hydrophobic separation membrane and the second hydrophobic separation membrane. The filter for a water treatment device according to claim 12, wherein the hydrophobic separation membrane prevents water located on both sides of the hydrophobic separation membrane from permeating. The filter for a water treatment device according to claim 12, wherein the hydrophobic membrane has a thickness of 10 to 20 μm.