CN113401989A

CN113401989A - Filter core and separator

Info

Publication number: CN113401989A
Application number: CN202010184101.4A
Authority: CN
Inventors: 陈小平
Original assignee: Foshan Viomi Electrical Technology Co Ltd
Current assignee: Guangdong Lizi Technology Co Ltd
Priority date: 2020-03-16
Filing date: 2020-03-16
Publication date: 2021-09-17

Abstract

A bipolar membrane filter core and an electrodeionization device with the filter core are provided with a membrane structure formed by radially winding more than one bipolar membrane; the bipolar membrane is in a linear flow channel or is bent at least once from the water inlet to the water outlet in an unfolding state. According to the invention, the spiral flow channel is adopted, the length of the flow channel is prolonged, the retention time of water flow in the filter element is prolonged, and thus the desalting efficiency can be improved. The desalination efficiency of high-concentration brine can be realized under the condition of not increasing the membrane area and the volume of the filter element. The bipolar membrane structure is adopted, and the ion exchange efficiency is high.

Description

Filter core and separator

Technical Field

The invention relates to the technical field of water treatment, in particular to a bipolar membrane filter core and an electrodeionization device with the same.

Background

Ion exchange is one of the methods for extracting or removing ions from a liquid stream using ion exchange materials. Currently, ion exchange has been widely used for water purification and softening; desalting seawater and brackish water; refining and decolorizing solution (such as sugar solution). The ion exchange material has an ion exchange membrane in addition to the ion exchange resin beads and powder. The ion exchange membrane is a membrane which contains ion exchange groups and is made of high polymer materials, wherein the membrane contains all cation exchange groups and is a cation exchange membrane, and the membrane contains all anion exchange groups and is an anion exchange membrane.

However, in the prior art, the flow channel of the filter element in the electrodeionization system is generally designed to flow out along the transverse direction of the membrane, the retention time of raw water in the flow channel is short, the desalination effect is poor, and the application of the filter element in a large-flux and high-salt concentration area is limited.

Therefore, it is necessary to provide a bipolar membrane filter element and an electrodeionization device having the same to overcome the deficiencies of the prior art.

Disclosure of Invention

The invention aims to avoid the defects of the prior art and provides a bipolar membrane filter core and an electrodeionization device with the same, which can prolong the length of a flow channel and improve the desalination efficiency.

The object of the invention is achieved by the following technical measures.

Provided is a bipolar membrane filter element provided with a membrane structure formed by radially winding one or more bipolar membranes and a spiral flow channel formed by winding the bipolar membranes.

Preferably, after the bipolar membrane constituting the membrane structure is unfolded, one side parallel to the central axis of the membrane structure is defined as a side edge of the bipolar membrane, and one side perpendicular to the central axis is defined as an end edge; the water inlet of the flow channel is arranged on the side edge or the end edge of the bipolar membrane, and the water outlet of the flow channel is arranged on the end edge or the side edge.

Preferably, in the bipolar membrane filter element, the middle cavity of the membrane structure is provided with a functional channel, and the functional channel is communicated with at least one of the water inlet and the water outlet of the flow channel.

Preferably, in the bipolar membrane filter element, the functional channel is provided with at least one functional area, and at least one functional area is communicated with the flow channel.

Preferably, in the bipolar membrane filter element, the functional channel has at least two functional areas, and one functional area is used for the liquid to be treated to enter and is communicated with the water inlet; the other functional area is used for discharging liquid to be treated; is communicated with the water outlet.

Preferably, in the bipolar membrane filter element, the functional channel is a central tube, and the central tube is provided with a through hole.

Preferably, in the bipolar membrane filter cartridge, the central tube is provided with a plurality of sub-tubes which are separated, wherein at least one sub-tube is provided with a through hole for communicating with the flow passage.

Preferably, the central tube of the bipolar membrane filter element at least comprises two sections of sub-tubes with through holes, wherein one section of sub-tube is used for the liquid to be treated to enter and communicate with the water inlet of the flow channel; the other section is used for discharging the treated liquid and is communicated with a water outlet of the flow passage.

In another preferred embodiment, the middle cavity of the membrane structure of the bipolar membrane filter element has a functional channel, and the functional channel is not communicated with the flow channel.

Preferably, in the bipolar membrane filter element, the functional channel is a central tube or a support net or a support frame.

Preferably, in the bipolar membrane filter element, the flow channel of the bipolar membrane is a linear flow channel in the unfolded state.

In another preferred embodiment, in the bipolar membrane filter element, the flow channel is turned at least once from the water inlet to the water outlet in the unfolded state of the bipolar membrane.

Preferably, in the bipolar membrane filter element, the flow channel makes two to ten turns.

Preferably, the bipolar membrane filter element has a non-turning position of the flow channel, wherein the flow direction of the water flow is perpendicular to the central axis of the membrane structure, or the flow direction of the water flow is parallel to the central axis of the membrane structure.

Preferably, the water inlet and the water outlet of the bipolar membrane filter element connected with the same flow channel are distributed on the same side or different sides of the corresponding bipolar membrane.

Preferably, the central tube of the bipolar membrane filter cartridge at least comprises two sections of sub-tubes with through holes, wherein one section of the sub-tube is used for the liquid to be treated to enter, and the other section of the sub-tube is used for the treated liquid to be discharged.

Preferably, the water inlet and the water outlet of the bipolar membrane filter element connected with the same flow channel are arranged at the bipolar membrane or at a central tube with a through hole.

Preferably, the bipolar membrane filter element is provided with a plurality of bipolar membranes, and the bipolar membranes are stacked and radially wound to form a membrane structure;

the water inlets of all the flow channels are communicated, the water outlets of all the flow channels are communicated, and other positions of different flow channels are not communicated.

the water outlet of at least one previous stage of flow channel is connected with the water inlet of at least one next stage of flow channel, and the water flow is discharged from the water outlet of the last stage of flow channel.

Preferably, the bipolar membrane filter core further comprises a diversion net, and at least one diversion net is arranged between the electrode and the bipolar membrane and between the bipolar membrane and the bipolar membrane.

Preferably, the bipolar membrane cartridge is further provided with at least one pair of electrode sets, each electrode set comprises at least one porous electrode, one electrode is arranged in the functional channel of the membrane structure, and the other electrode is sleeved outside the membrane structure.

Preferably, the bipolar membrane filter element is positioned at the electrode and is columnar; or

The electrode is a solid electrode formed by winding a sheet-shaped electrode; or

The electrode wire is coiled into a spiral shape; or

The tube shape is hollow or non-hollow;

the electrode sleeved outside the membrane structure is cylindrical, elliptic cylindrical, square cylindrical, triangular cylindrical or irregular cylindrical; or a spiral coiled by the electrode wire.

Preferably, in the bipolar membrane cartridge, the porous electrode is provided with a porous material.

Preferably, in the bipolar membrane filter element, the porous material is one or more of activated carbon, carbon black, carbon nanotubes, graphite, carbon fibers, carbon cloth, carbon aerogel, metal powder, metal oxide and conductive polymer.

Preferably, in the bipolar membrane cartridge, the porous electrode further includes a current collector, and the current collector and the porous material are stacked.

Preferably, in the bipolar membrane cartridge, the porous electrode is further provided with an ion exchange membrane, and the porous material and the ion exchange membrane are stacked.

The invention also provides a roll type bipolar membrane electrodeionization device which is provided with the bipolar membrane filter element.

The invention relates to a bipolar membrane filter element and an electrodeionization device with the same, which are provided with a membrane structure formed by radially winding more than one bipolar membrane and a spiral flow channel formed by winding the bipolar membrane. According to the invention, the spiral flow channel is adopted, the length of the flow channel is prolonged, the retention time of water flow in the filter element is prolonged, and thus the desalting efficiency can be improved. The desalination efficiency of high-concentration brine can be realized under the condition of not increasing the membrane area and the volume of the filter element. The bipolar membrane structure is adopted, and the ion exchange efficiency is high.

Drawings

The invention is further illustrated by means of the attached drawings, the content of which is not in any way limiting.

Fig. 1 is a schematic structural view of a long flow channel rolled bipolar membrane cartridge according to embodiment 1 of the present invention. Fig. 1(a) to (i) are schematic diagrams of seven different implementations.

Fig. 2 is a schematic view of a structure of a bipolar membrane cartridge of example 2 of the present invention.

FIG. 3 is another schematic diagram of the structure of a bipolar membrane cartridge of example 2 of the present invention.

Fig. 4 is another schematic structural diagram of a bipolar membrane cartridge according to example 2 of the present invention, wherein fig. 4(a), (b), (c), and (d) show four different implementations.

Fig. 5 is another schematic structural view of a bipolar membrane cartridge of example 2 of the present invention, wherein fig. 5(a), (b) show two different implementations.

Fig. 6 is a schematic structural diagram of a bipolar membrane cartridge of example 3 of the present invention, wherein fig. 6(a), (b), (c), and (d) are four different implementations.

FIG. 7 is a schematic structural view of a bipolar membrane cartridge of example 4 of the present invention.

Fig. 8 is a sectional view "B-B" of fig. 7.

FIG. 9 is a schematic illustration of the bipolar membrane cartridge of FIG. 7 in a partially desalinated state.

FIG. 10 is a schematic illustration of the bipolar membrane cartridge of FIG. 7 in a partially positioned regeneration mode.

Fig. 11 is a schematic representation of a multi-layer bipolar wound membrane configuration of example 5 of a bipolar membrane cartridge of the present invention.

FIG. 12 is a schematic structural view of a bipolar membrane cartridge of example 6 of the present invention.

FIG. 13 is a schematic structural diagram of a porous electrode in example 8 of the bipolar membrane cartridge of the present invention.

FIG. 14 is a schematic structural view of a porous electrode in example 9 of the bipolar membrane cartridge of the present invention.

In fig. 1 to 14, there are included:

electrode 100, electrode 200,

A bipolar membrane 300, a cation exchange membrane 310, an anion exchange membrane 320,

A membrane structure 30,

A central tube 500, a through hole 510,

A sealing area 400,

A current collector 130, a porous material 110, an anion exchange membrane 120.

Detailed Description

The invention is further illustrated by the following examples.

Unless clearly defined otherwise herein, the scientific and technical terms used have the meaning commonly understood by those of skill in the art to which this application pertains. As used in this application, the terms "comprising," "including," "having," or "containing" and similar referents to shall mean that the content of the listed items is within the scope of the listed items or equivalents thereof.

In the specification and claims, the singular and plural of all terms are not intended to be limiting unless the context clearly dictates otherwise. The use of "first," "second," and similar language in the description and claims of this application does not denote any order, quantity, or importance, but rather the intention is to distinguish one material from another, or embodiment.

Unless the context clearly dictates otherwise, the term "or", "or" does not mean exclusively, but means that at least one of the mentioned items (e.g. ingredients) is present, and includes the case where a combination of the mentioned items may be present.

References in the specification to "some embodiments" or the like indicate that a particular element (e.g., feature, structure, and/or characteristic) described in connection with the invention is included in at least one embodiment described in the specification, and may or may not be present in other embodiments. In addition, it is to be understood that the described inventive elements may be combined in any suitable manner.

Reference herein to "deionization" is to the removal of ions from the liquid to be treated, including anions and cations in various valence states. In most cases, "deionization" has the same meaning as "desalination". In some cases, deionization is also referred to as demineralization.

Example 1.

A bipolar membrane filter element is provided with a membrane structure formed by radially winding more than one bipolar membrane and a spiral flow passage formed by winding the bipolar membranes. The length of the flow channel can be prolonged by adopting the spiral pipeline.

When the bipolar membrane is in an unfolded state, the flow channel is linear. After the bipolar membrane forming the membrane structure is unfolded, one side parallel to the central axis of the membrane structure is defined as the side edge of the bipolar membrane, and the other side perpendicular to the central axis is defined as the end edge; the water inlet of the flow channel is arranged on the side edge or the end edge of the bipolar membrane, and the water outlet of the flow channel is arranged on the end edge or the side edge.

The lumen site of the membrane structure may have a functional channel that may be in communication with at least one of the water inlet or the water outlet of the flow channel. The functional channel is provided with at least one functional area, and at least one functional area is communicated with the flow channel. The functional channel can also be provided such that there are at least two functional areas, one for the entry of the liquid to be treated and one for the exit of the liquid to be treated.

The middle cavity of the membrane structure is provided with a functional channel, and the functional channel can not be communicated with the flow channel. This case also makes it possible to realize the bent flow path of the present embodiment. In this case, the water inlet or outlet of the flow channel is arranged at the end edge or side edge position of the bipolar membrane.

The functional channel may be a central tube, which is provided with openings as required depending on whether it is to be in communication with the flow channels. The functional channel can be only a cavity formed in the process of spirally winding the bipolar membrane, can also be a support structure made of plastic, metal or other materials, and the like, and can also be a section of the bipolar membrane adopted in the process of winding the bipolar membrane as the functional channel.

The functional passage may be an inlet passage for raw water or a discharge passage for pure water, or both an inlet port for raw water and an outlet port for pure water, or only a supported or unsupported space or structure, etc.

The present invention will be described below by taking a center pipe as an example of the functional passage.

As shown in fig. 1, the long flow channel wound bipolar membrane cartridge is further provided with a central tube 500 and a membrane structure 30 formed by more than one bipolar membrane 300 in radial direction. The central tube 500 has at least one through hole 510 for allowing water to flow through the central tube 500 into the flow channel or for allowing liquid in the flow channel to be introduced into the central tube 500 through the through hole 510 and discharged from the central tube.

The bipolar membrane 300 is composed of a cation exchange membrane 310 and an anion exchange membrane 320 which are attached together, and the cation exchange membrane and the anion exchange membrane which form the same bipolar membrane are clamped tightly without a binder; the cation exchange membrane and the anion exchange membrane may be formed by thermal bonding. No flow channel is formed between the cation exchange membrane and the anion exchange membrane, and a flow channel is formed between the bipolar membrane and the bipolar membrane or a flow channel is formed between the bipolar membrane and the electrode. The bipolar membranes sold in the market can be used as the bipolar membranes in the scheme, and the details are not repeated.

The bipolar membrane 300 is wound radially around the central tube 500 to form a helical flow channel, and a water inlet or outlet is provided at the end of the membrane structure, into or from which liquid can be introduced or discharged.

It should be noted that the membrane forms a flow channel, only the inlet and outlet of the flow channel can pass through the flow channel, and the other part is a sealing area 400, which is in a sealing shape and can be sealed by means of a sealing adhesive tape or a hot melt adhesive. This is common knowledge in the art, and the detailed description is not repeated in this embodiment.

The filter element is generally provided with a filter element shell to provide installation support for relevant components, an outer electrode component is arranged in the shell, and an electrode positioned in a central tube is columnar; or may be a solid electrode formed by winding a sheet-like electrode; or can be a spiral coiled by the electrode wire; or hollow or non-hollow cylindrical; or a plane formed by coiling filaments, a hollow or non-hollow sheet, or a flat net, or can be co-injection molded with the filter element shell. The electrode sleeved outside the membrane structure can be cylindrical, elliptic, square, triangular or irregular; or a spiral coiled by the electrode wire. The electrode material can be inert metal such as titanium, gold, platinum and the like, or ruthenium iridium coated metal, and can also be non-metal electrode, such as capacitance electrode, graphite electrode and any electrode part capable of forming an electric field.

The bipolar membranes are stacked together in the same direction, meaning that the anode membranes are all facing in one direction. The flow channel between the two bipolar membranes can be made of a flow guide net material such as polypropylene, nylon, polyester and the like, and the thickness of the flow channel is 0.05-2 mm. If the bipolar membrane surface is provided with the concave-convex structural characteristics, the structure of peaks and valleys formed by the concave-convex characteristics can naturally form a flow channel between two membranes when a plurality of membranes are laminated, and no additional flow guide net is needed.

The desalting effect of the liquid in the filter element is firstly related to the length of the flow channel in the filter element. In order to improve the length of the flow channel, the bipolar membrane is radially wound around the central tube to form a spiral flow channel, so that the length of the flow channel is greatly improved.

Seven bipolar membranes are shown in FIGS. 1(a) to (g) and are implemented in a straight flow channel after being unfolded. In fig. 1(a), one end of the central tube 500 is used as a water inlet, the side of the bipolar membrane is used as a water outlet, raw water enters the central tube 500, enters the flow channel through the through hole formed in the central tube 500, and is discharged from the water outlet on the side of the bipolar membrane. In fig. 1(b), raw water enters from the center pipe and is discharged from the edge side water outlet of the bipolar membrane. In fig. 1(c), raw water enters from the center tube and is discharged from the end edge water outlet on the other side of the bipolar membrane. In fig. 1(d), raw water enters from a water inlet provided at an end edge of an upper end, and is discharged from a water outlet provided at an end edge of the other side after being treated by a spiral flow channel.

Fig. 2 shows another mode, in which the side of the membrane structure is the water inlet, and one end of the central tube 500 is the water outlet. Raw water enters the flow channel from the water inlet on the side edge at the same time, and is discharged from the central pipe after being desalted by the flow channel.

Fig. 3 shows another way, in which both ends of the central tube 500 are used as water inlets and the side edges of the bipolar membrane are used as water outlets. Raw water simultaneously enters from two ends of the central pipe 500, enters the flow channel through the through hole 510, and is discharged from the side edge of the bipolar membrane after the dragging treatment.

It should be noted that the flow channel direction listed in this embodiment can be changed, that is, the water inlet is used as the water outlet, the water outlet is used as the water inlet, and the requirement of extending the flow channel in this patent is also satisfied.

It should be noted that the flow channel, the water inlet and the water outlet illustrated in this embodiment are only some examples. In practice, the solution of this patent is suitable as long as the liquid flow is purified by passing through the spiral flow channel.

The long-flow-channel roll type bipolar membrane filter core adopts a bipolar membrane structure, and has high ion exchange efficiency. The bipolar membrane is wound on the central tube to form a spiral flow channel, so that the length of the flow channel is prolonged, the retention time of water flow in the filter element is prolonged, and the desalting efficiency can be improved. The desalination efficiency of high-concentration brine can be realized under the condition of not increasing the membrane area and the volume of the filter element.

Example 2.

The bipolar membrane is in an unfolded state, and a flow channel is turned at least once from the water inlet to the water outlet.

Because the flow channel is turned at least once, the length of the flow channel is prolonged, the retention time of water flow in the filter element is prolonged, and the desalting efficiency can be improved. Preferably the flow path may make two to ten turns. It should be noted that the turn times of the flow channel refers to the change of the water flow direction in the front and back flow channels, and may be 180 degrees or 90 degrees. The turning in this embodiment does not include the turning at the curved joint, and the curved joint is regarded as a connecting pipeline of the front and rear flow passages in different directions.

At the non-turning position of the flow channel, the flow direction of the water flow may be perpendicular to the central axis of the membrane structure winding, or the flow direction of the water flow may be parallel to the central axis of the membrane structure winding.

The requirement of the flow channel is realized, and the water inlet and the water outlet which are connected with the same flow channel can be distributed on the same side or different sides of the corresponding bipolar membrane. After the bipolar membrane forming the membrane structure is unfolded, one side parallel to the central axis of the membrane structure is defined as a side edge of the bipolar membrane, one side perpendicular to the central axis is defined as an end edge, a water inlet corresponding to the flow channel can be arranged on the side edge or the end edge of the bipolar membrane, and a water outlet of the flow channel can also be arranged on the end edge or the side edge.

The functional channel may be a central tube, which is provided with openings as required depending on whether it is to be in communication with the flow channels. The functional channel can also be only a cavity formed in the process of spirally winding the bipolar membrane, can also be a support structure made of plastic, metal or other materials, and the like, and can also be a section of the bipolar membrane adopted in the process of winding the bipolar membrane as the functional channel.

The invention will now be described with reference to a central tube as the functional channel.

A bipolar membrane filter element is provided with at least one pair of electrodes. As shown in fig. 2, the bipolar membrane cartridge is further provided with a central tube 500 and a membrane structure 30 in which one or more bipolar membranes 300 are radially wound around the central tube 500. In the unfolded state, the flow channel passes through at least one 180-degree turn from the water inlet to the water outlet, and preferably passes through two to ten turns.

The bipolar membrane 300 is radially wound around the central tube 500 to form a spiral flow channel, and both ends of the flow channel are respectively communicated with the water inlet and the water outlet.

The bipolar membrane cartridge has a flow direction perpendicular to the axis of the central tube at a non-turning position of the flow channel. The water inlet and the water outlet which are connected with the same flow passage are distributed on the same side or different sides of the corresponding bipolar membrane. The inlet of the flow channel may be provided at the bipolar membrane or at the center tube 500 having the through-hole 510. The water outlet of the flow channel can also be arranged at the bipolar membrane or at a central tube with through holes.

The bipolar membrane filter element has the advantages that the central tube can be provided with multiple sections of sub-tubes which are separated, and at least one section of sub-tube is provided with a through hole which is used for being communicated with a flow channel. Or the central pipe at least comprises two sections of sub-pipes with through holes, wherein one section of the sub-pipe is used for the liquid to be treated to enter, and the other section of the sub-pipe is used for the treated liquid to be discharged. By means of the divided multi-segment sub-tubes, correspondingly desired functional areas can be formed.

Fig. 2 shows an extended flow path, with liquid entering and exiting through the central tube. The central tube 500 contains two sections of sub-tubes with through holes, one for the entry of the liquid to be treated and the other for the exit of the treated liquid. Both sections of sub-pipe are provided with through holes 510. Raw water enters the flow channel from the sub-pipe at one end through the through hole arranged on the sub-pipe, changes the flow direction at the turning part of the flow channel, enters the other section of the sub-pipe through the through hole arranged on the other section of the sub-pipe, and purified pure water is discharged from the other section of the sub-pipe.

It should be noted that the number of the sub-pipes can be set according to the number of times of changing the flow channel, and the sub-pipe which is used as the liquid flow inlet and the sub-pipe which is used for liquid flow discharge are generally provided with through holes. The sub-tubes that do not undergo fluid exchange are not provided with through holes.

FIG. 3 is another way of extending the flow channel, in which the inlet of the liquid is arranged at the central tube and the outlet of the liquid is arranged at the bipolar membrane. In this manner, the center tube contains two subsections, one section having through holes 510 and the other section having no through holes. The liquid enters the subsection with the through hole and enters the flow channel through the through hole, and the purified pure water is discharged from a water outlet at the tail end of the flow channel.

Fig. 4 shows another way of extending the flow channel, where the flow channel makes two turns in the direction of the water flow. The central tube has two separate sections of sub-tubes, one section of sub-tube having through holes 510 and the other section having no through holes. The water outlet of the flow channel is arranged at the tail end of the bipolar membrane. The liquid enters the subsection with the through hole and enters the flow channel through the through hole, and the purified pure water is discharged from a water outlet at the tail end of the flow channel. Fig. 4(a), (b), (c) and (d) show four flow channels and flow modes of the water inlet and the water outlet arranged at different positions.

FIG. 5 shows another way of extending the flow path, where the liquid enters and exits through the bipolar membrane. The center tube 500 contains two sections with sub-tubes, neither of which has a through hole. The water inlet and the water outlet are both arranged at the bipolar membrane. Raw water enters the flow channel from the water inlet, changes the flow direction through the turning part of the flow channel and enters the other section of the flow channel, and the purified bipolar membrane is discharged from the water outlet. Fig. 5(a) and (b) show two flow channels and flow modes of the water inlet and the water outlet arranged at different positions.

The bipolar membrane filter core adopts a bipolar membrane structure, and has high ion exchange efficiency. The bipolar membrane is wound on the central tube to form a spiral flow channel, the length of the flow channel is prolonged by at least one turning of the flow channel, the retention time of water flow in the filter element is prolonged, and the desalting efficiency can be improved. The desalination efficiency of high-concentration brine can be realized under the condition of not increasing the membrane area and the volume of the filter element.

It should be noted that the water inlet and the water outlet in this embodiment can be exchanged, and accordingly, the flow direction in the flow channel is correspondingly changed.

Example 3.

A bipolar membrane cartridge, otherwise characterized as in example 1, except that: in the non-turning position of the flow channel, the flow direction of the water flow is parallel to the axis of the central tube.

The water inlet and the water outlet which are connected with the same flow passage of the bipolar membrane filter core can be distributed on the same side or different sides of the corresponding bipolar membrane. The water inlet and the water outlet which are connected with the same flow channel are arranged at the bipolar membrane or at the central tube with a through hole.

Fig. 6 shows a manner of extending the flow channel according to this embodiment, in which the bipolar membrane is provided with a water inlet and a water outlet, and pure water is discharged from the water outlet of the bipolar membrane after the raw water enters the flow channel from the water inlet and the flow is diverted twice. As shown in FIGS. 6(a), (b), (c) and (d), four flow channels and flow modes are provided at different positions of the water inlet and the water outlet.

In this embodiment, liquid enters and exits through the water inlet and the water outlet which are arranged on the bipolar membrane. The water inlet or the water outlet can also be arranged on the central tube, and the water enters the flow channel or is discharged from the flow channel through the through hole arranged on the central tube.

Example 4.

A bipolar membrane cartridge comprises an electrode pair consisting of a pair of

electrodes

100, 200, a central tube 500 and a bipolar membrane 300 wound around the central tube, as shown in FIG. 7. The electrode 100 is arranged in the central tube 500, the bipolar membrane 300 is radially wound on the central tube 500 to form a spiral membrane structure, and the other electrode 200 is sleeved outside the membrane structure. The bipolar membrane of the membrane structure is wound to form a spiral flow channel.

In this embodiment, bipolar membrane 300 is longitudinally wound around central tube 500, as viewed in the section "B-B" of fig. 7, forming a spiral flow path. Fig. 8 illustrates a sectional view B-B taken from a cut-away position, in which sector-shaped area portions are indicated by color blocks to indicate a cation exchange membrane 310 and an anion exchange membrane 320 in the bipolar membrane, and a water flow passage enters a flow passage formed by rotation of the bipolar membrane from a through hole of a center tube 500 and is discharged from the end of the membrane structure.

The desalination process of the rolled bipolar membrane cartridge is shown in fig. 9. When desalination is carried out for a while, reverse-polarity regeneration is required to release ions in water adsorbed on the bipolar membrane, as shown in FIG. 10.

It should be noted that, between the two electrodes, the number of layers of bipolar membrane winding can be flexibly set according to the needs, and is not limited to the case of the present embodiment.

It should be noted that, after the bipolar membrane is unfolded, the flow direction of the filter element with the straight flow channel is consistent in a cross section view of 'B-B' cut from all positions. After the bipolar membrane is unfolded correspondingly, the flow channel is bent and flows out at different cutting positions, and the directions of liquid flows can be different.

The bipolar membrane in this embodiment is a single-layer bipolar membrane, but in practice, after a plurality of bipolar membranes are stacked, the electrode 100 may be radially wound as a whole to form a spiral membrane structure. The number of the bipolar membranes stacked may be 2 or 3 or other numbers.

The rolled bipolar membrane filter core repeatedly utilizes the membrane area of the bipolar membrane, and the speed and the efficiency of ion exchange are greatly improved by the electrolytic ion exchange mode.

The bipolar membrane filter core adopts a bipolar membrane structure, and has high ion exchange efficiency. The bipolar membrane is wound on the central tube to form a spiral flow channel, so that the length of the flow channel is prolonged, the retention time of water flow in the filter element is prolonged, and the desalting efficiency can be improved. The desalination efficiency of high-concentration brine can be realized under the condition of not increasing the membrane area and the volume of the filter element.

Example 5.

A bipolar membrane cartridge, other features are the same as those of example 4, except that a plurality of bipolar membranes are provided, and the plurality of bipolar membranes are stacked with a radially wound central tube. The central tube is communicated with the initial winding positions of the bipolar membranes, and the tail end positions of the bipolar membranes are water outlets. As shown in FIG. 11, there are four bipolar membranes wound.

This structural arrangement, rivers can get into a plurality of spiral runners simultaneously, discharge through every spiral runner, can shorten the time of water treatment.

Example 6.

A bipolar membrane cartridge, other features of which are the same as those of one of embodiments 1 or 2 or 3 or 4 or 5, except that in this embodiment, a plurality of bipolar membranes are provided, and the plurality of bipolar membranes are stacked with a radially wound center tube. The water outlet of at least one previous stage of flow channel is connected with the water inlet of at least one next stage of flow channel, and the water flow is discharged from the water outlet of the last stage of flow channel. The flow channel is prolonged by the serial connection mode.

FIG. 12 is a schematic view showing a method of extending a flow path in series, in which raw water is introduced from a water inlet provided in a bipolar membrane of a previous stage and discharged from a water outlet, and then introduced into a water inlet provided in a bipolar membrane of a next stage, and purified pure water is discharged from a water outlet of the bipolar membrane of the next stage.

It should be noted that fig. 12 is only an illustrative manner, and may be flexibly set according to actual requirements.

According to the filter element, the flow channels formed by different bipolar membranes are connected in series and then discharged, the length of the flow channels can be prolonged, the flow of liquid desalination in the flow channels is increased, and the desalination efficiency is greatly improved. The desalination efficiency of high-concentration brine can be realized under the condition of not increasing the membrane area and the volume of the filter element.

Example 7.

A bipolar membrane filter element is characterized in that the bipolar membrane filter element is the same as any one of the embodiments 1 to 6, except that a flow guide net is arranged between an electrode and the bipolar membrane and between the bipolar membrane and the bipolar membrane, wherein the flow guide net material comprises a net material such as polypropylene, nylon, polyester and the like, and the thickness of the net material is 0.05-2 mm. And a flow channel is formed through the flow guide net, so that the bipolar membrane filter core can accurately and effectively work.

Example 8.

A bipolar membrane cartridge, otherwise characterized as in examples 1 to 7, except that at least one porous electrode is included in a pair of electrode groups.

The pair of electrode groups may be composed of two porous electrodes, or may be composed of one porous electrode and one common electrode. Common electrodes such as metal electrodes, titanium electrodes with ruthenium-yttrium coatings, ruthenium-yttrium electrodes, carbon electrodes, graphite electrodes, etc.

Among them, the porous electrode may be composed of a porous material, or a porous material and a current collector laminated, or a current collector, a porous material, and an ion exchange membrane laminated in this order. The ion exchange membrane is an anion exchange membrane or a cation exchange membrane, and when the ion exchange membrane is contained, the ion exchange membrane in the porous electrode is close to the bipolar membrane. The cation exchange membrane or the anion exchange membrane in the porous electrode can be flexibly selected according to actual needs.

The porous material may be any electrically conductive material having a large specific surface, e.g. a specific surface of more than 100m²Conductive material per gram. In some embodiments, the porous material is a hydrophobic, electrically conductive material. The porous material has a porous structure with pore sizes between 0.5 and 50 nanometers. The porous material can be an electric conductor prepared from one or more of activated carbon, carbon black, carbon nanotubes, graphite, carbon fibers, carbon cloth, carbon aerogel, metal powder (such as nickel), metal oxide (such as ruthenium oxide) and conductive polymer. In one embodiment, the porous material is a sheet or plate structure made of activated carbon and having a thickness in the range of 100 to 5000 micrometers, preferably 200 to 2,500 micrometers, and the pore size of the activated carbon sheet structure is between 0.5 to 20 nanometers, preferably 1 to 10 nanometers.

The porous electrode can reduce the scaling risk of the roll type bipolar membrane filter element. Since the ion exchange membrane contains or is adsorbed with ion charge units, when the amount of ions at the porous electrode is insufficient to complete the desorption process, the excess charge on the electrode is buffered by releasing the ions in the ion exchange membrane to help complete the desorption process. In this way, the risk of fouling is greatly reduced.

The current collector is used to connect to a wire or power source, also referred to as a "current collector". The current collector is formed of one or more materials selected from the group consisting of metals, metal alloys, graphite, graphene, carbon nanotubes, and conductive plastics. The current collector may be in any suitable form such as a plate, mesh, foil or sheet. In some embodiments, the current collector may be made of a metal or metal alloy, suitable metals include titanium, platinum, iridium or rhodium, etc., preferably titanium, and suitable metal alloys may be stainless steel, etc. In other embodiments, the current collector may be made of a conductive carbon material, such as graphite, graphene, carbon nanotubes, and the like. In other embodiments, the current collector is made of a conductive plastic material, such as a polyolefin (e.g., polyethylene), and conductive carbon black or metal particles, etc., may be mixed therein. In some embodiments, the current collector is a sheet or plate-like structure and may have a thickness in the range of 50 micrometers to 5 millimeters. In some embodiments, the current collector and the porous electrode have substantially the same shape and/or size.

When the porosity and conductivity of the porous material are sufficient, the current collector may not be provided when the porous material itself functions as the current collector.

The rolled bipolar membrane filter element of the embodiment can be composed of a plurality of electrode groups, and when the rolled bipolar membrane filter element comprises a plurality of electrode groups, the electrode groups can be connected in series or in parallel or in series-parallel or in parallel-series and parallel-parallel series-parallel connection mode for flow passage connection. In the present specification, the terms "in series" and "in parallel" are defined in consideration of the flow direction of the flow path liquid flow output liquid. For example, if two electrode sets are connected in series, the product fluid from the flow channel of the previous electrode set enters the flow channel of the next electrode set. For another example, if two electrode sets are connected in parallel, it means that the flow channels of the two electrode sets receive the same liquid. The series set of electrodes is used to further remove ions from the liquid, while the parallel set of electrodes is used to increase the throughput of the device.

The rolled bipolar membrane cartridge of the present embodiment includes an electrode pair formed by a pair of

porous electrodes

100 and 200, a central tube, and a bipolar membrane 300 wound around the central tube. In the present embodiment, the porous electrode 100 is formed by laminating the current collector 130 and the porous material 110 as shown in fig. 13. The porous electrode 200 is formed by sequentially laminating a current collector and a porous material. The porous electrode can be formed by laminating and clamping a current collector and a porous material together without using a binder; or may be fixed by thermal bonding or bonded by an adhesive.

When the roll type bipolar membrane filter element is used, the porous material is directly contacted with the flow channel, and the bipolar membrane between the porous electrodes is arranged in the same way. In the manner of this example, desalination and regeneration can be achieved. Under the desalting condition, the porous material can adsorb anions and cations in raw water, and has no selectivity and the adsorption efficiency of about 50 percent. Under the regeneration condition, anions and cations in the porous material can be desorbed into the flow channel to realize the regeneration.

The roll type bipolar membrane filter core has a simple water path structure. The rolled bipolar membrane filter core repeatedly utilizes the membrane area of the bipolar membrane, and the speed and the efficiency of ion exchange are greatly improved by the electrolytic ion exchange mode. The roll type bipolar membrane filter core of the invention can not generate gas in polar water and can not cause scaling phenomenon.

So this formula of book bipolar membrane filter core adopts porous electrode and bipolar membrane's structure, can avoid among the prior art the problem that the pole water hydrolysis produced gas and scale deposit, and can improve the desalination, has the characteristics that the system water rate is high, the water waste is few.

In addition, experiments show that the whole desalting efficiency of the electrodeionization device adopting the porous electrode can be improved by more than 8% compared with that of the conventional electrode. This is because the porous electrode can adsorb ions of raw water, and this adsorption efficiency is higher than the ion exchange efficiency of the bipolar membrane.

The electrode 100 located at the center may be a columnar shape, a solid or hollow electrode formed by winding a sheet-shaped electrode, a spiral shape formed by coiling an electrode wire, a hollow or non-hollow cylindrical shape, or the like, and may be specifically selected according to actual conditions.

The electrode 200 sleeved outside the membrane structure may be cylindrical, elliptic cylindrical, square cylindrical, triangular cylindrical or irregular cylindrical, or may be spiral formed by coiling electrode wires, and the like, and may be selected according to actual situations, which are not listed herein.

The filter core of this embodiment can prolong the length of runner, increases the flow of liquid in the runner desalination, promotes desalination efficiency by a wide margin. The desalination efficiency of high-concentration brine can be realized under the condition of not increasing the membrane area and the volume of the filter element.

Example 9.

A rolled bipolar membrane cartridge, other features are the same as those of embodiment 8 except that in this embodiment: as shown in fig. 14, the porous electrode 100 is formed by stacking a current collector 130, a porous material 110, and an anion exchange membrane 120 in this order, and the porous electrode 100 is a cathode membrane electrode; the porous electrode 200 is also formed by stacking a current collector, a porous material, and a cation exchange membrane in this order, and the porous electrode 200 is an anode membrane electrode. The porous electrode can be formed by overlapping and clamping a current collector, a porous material and an ion exchange membrane together without using a binder; or may be fixed by thermal bonding or bonded by an adhesive.

Experiments show that the whole desalting efficiency of the electrodeionization device adopting the porous electrode can be improved by more than 10% compared with that of the electrodeionization device adopting the common electrode, and the desalting efficiency is improved by a higher degree than that of the structure in the embodiment 1. This is because the porous electrode can adsorb ions of raw water, and this adsorption efficiency is higher than the ion exchange efficiency of the bipolar membrane. It can be seen that the electrodeionization apparatus of this example using porous electrodes is excellent in overall performance.

Example 10.

A rolled bipolar membrane cartridge, other features being the same as those of embodiment 8 or 9 except that: the porous electrode is not provided with a collector, and is formed only by laminating a porous material and an ion exchange membrane. The porous material of the present embodiment has a conductive property that satisfies the requirement of conductivity, and therefore, does not need to be provided with a collector.

It should be noted that the specific structure of the two porous electrodes can be flexibly set according to the need, for example, one porous electrode has a collector, the other porous electrode has no collector, or two porous electrodes have collectors at the same time or two porous electrodes have no collectors at the same time, as long as the actual need is met.

Example 11.

A bipolar membrane electrodeionization device having a rolled bipolar membrane filter cartridge as in any one of embodiments 1 to 10. The bipolar membrane electrodeionization device comprises a filter element, a pipeline and a power supply, and can independently carry out desalination and regeneration on water. Due to the adoption of the bipolar membrane, the desalination rate can be improved, and the method has the characteristics of high water production rate and less water resource waste.

The bipolar membrane electrodeionization device of the embodiment has the advantages that the length of the flow channel is prolonged by the filter element, so that the flow of liquid desalting in the flow channel is increased, the desalting efficiency is greatly improved, and the desalting efficiency of high-concentration brine can be realized under the condition that the membrane area and the volume of the filter element are not increased.

Example 12.

A water treatment device having a rolled bipolar membrane cartridge according to any one of embodiments 1 to 10, which can be used for industrial or domestic water treatment. Examples of uses of industrial water treatment facilities mentioned herein include, but are not limited to, industrial sewage treatment, municipal sewage treatment, seawater desalination, brine treatment, river and lake water treatment, cheese whey demineralization, and the like. The industrial water treatment apparatus includes, in addition to the rolled bipolar membrane cartridge of an embodiment of the present invention, one or more of, for example, a flocculation and/or coagulation unit, an advanced oxidation unit, an adsorption unit, an electrolysis unit, a membrane separation unit (including one or more of microfiltration, ultrafiltration, nanofiltration and reverse osmosis).

The household water treatment device according to the embodiment of the present invention generally includes one or more of an ultrafiltration unit, a nanofiltration unit, an activated carbon adsorption unit, and an ultraviolet sterilization unit, in addition to the rolled bipolar membrane filter element, the pipeline, and the power supply device according to the embodiment of the present invention.

This water treatment facilities, its roll-type bipolar membrane filter core adopt porous electrode and bipolar membrane's structure, can improve the desalination, and the system water rate is high, and water waste is few.

The water treatment equipment of the embodiment has the advantages that the length of the flow channel is prolonged by the filter element, so that the flow of liquid desalting in the flow channel is increased, the desalting efficiency is greatly improved, and the desalting efficiency of high-concentration brine can be realized under the condition that the membrane area and the volume of the filter element are not increased.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A bipolar membrane filter element is characterized in that: the device is provided with a membrane structure formed by radially winding more than one bipolar membrane and a spiral flow passage formed by winding the bipolar membranes.

2. The bipolar membrane cartridge of claim 1, wherein: after the bipolar membrane forming the membrane structure is unfolded, one side parallel to the central axis of the membrane structure is defined as the side edge of the bipolar membrane, and the other side perpendicular to the central axis is defined as the end edge; the water inlet of the flow channel is arranged on the side edge or the end edge of the bipolar membrane, and the water outlet of the flow channel is arranged on the end edge or the side edge.

3. The bipolar membrane cartridge of claim 1, wherein: the middle cavity position of the membrane structure is provided with a functional channel, and the functional channel is communicated with at least one of the water inlet or the water outlet of the flow channel.

4. The bipolar membrane ratio of claim 3, characterized in that: the functional channel is at least provided with one functional area, and at least one functional area is communicated with the flow channel.

5. The bipolar membrane cartridge of claim 4, wherein: the functional channel at least has two functional areas, one functional area is used for the liquid to be treated to enter and is communicated with the water inlet; the other functional area is used for discharging liquid to be treated; is communicated with the water outlet.

6. The bipolar membrane cartridge of claim 3, wherein: the functional channel is a central tube, and the central tube is provided with a through hole.

7. The bipolar membrane cartridge of claim 6, wherein: the central tube is provided with a plurality of sections of sub-tubes which are separated, wherein at least one section of sub-tube is provided with a through hole which is used for being communicated with the flow passage.

8. The bipolar membrane cartridge of claim 7, wherein: the central pipe at least comprises two sections of sub-pipes with through holes, wherein one section of the sub-pipe is used for the liquid to be treated to enter and be communicated with the water inlet of the flow channel; the other section is used for discharging the treated liquid and is communicated with a water outlet of the flow passage.

9. The bipolar membrane cartridge of claim 1, wherein: the middle cavity of the membrane structure is provided with a functional channel which is not communicated with the flow channel.

10. The bipolar membrane cartridge of claim 9, wherein: the functional channel is a central tube or a supporting net or a supporting frame.

11. The bipolar membrane cartridge of claim 1, wherein: when the bipolar membrane is in an unfolded state, the flow channel is a linear flow channel.

12. The bipolar membrane cartridge of claim 1, wherein: the bipolar membrane is in an unfolded state, and a flow channel is turned at least once from the water inlet to the water outlet.

13. The bipolar membrane cartridge of claim 12, wherein: the flow passage makes two to ten turns.

14. The bipolar membrane cartridge of claim 12, wherein: at the non-turning position of the flow channel, the flow direction of the water flow is perpendicular to the central axis of the winding of the membrane structure, or the flow direction of the water flow is parallel to the central axis of the winding of the membrane structure.

15. The bipolar membrane cartridge of claim 14, wherein: the water inlet and the water outlet which are connected with the same flow passage are distributed on the same side or different sides of the corresponding bipolar membrane.

16. A bipolar membrane cartridge according to any one of claims 1 to 15 wherein: the functional channel is a central tube, and the central tube is provided with a through hole.

17. The bipolar membrane cartridge of claim 16, wherein: the central tube is provided with a plurality of sections of sub-tubes which are separated, wherein at least one section of sub-tube is provided with a through hole which is used for being communicated with the flow passage.

18. The bipolar membrane cartridge of claim 16, wherein: the central tube at least comprises two sections of sub-tubes with through holes, wherein one section of the sub-tube is used for the liquid to be treated to enter, and the other section of the sub-tube is used for the treated liquid to be discharged.

19. The bipolar membrane cartridge of claim 16, wherein: the water inlet and the water outlet which are connected with the same flow channel are arranged at the bipolar membrane or at the central tube with a through hole.

20. A bipolar membrane cartridge according to any one of claims 1 to 15 wherein:

a plurality of bipolar membranes are arranged and radially wound to form a membrane structure;

21. A bipolar membrane cartridge according to any one of claims 1 to 15 wherein: a plurality of bipolar membranes are arranged and radially wound to form a membrane structure;

22. A bipolar membrane cartridge according to any one of claims 1 to 15 wherein: the bipolar membrane.

23. A bipolar membrane cartridge according to any one of claims 1 to 15 wherein: at least one pair of electrode groups is also arranged, the electrode group at least comprises a porous electrode, one electrode is assembled in the functional channel of the membrane structure, and the other electrode is sleeved outside the membrane structure.

24. The bipolar membrane cartridge of claim 23, wherein: the porous electrode is provided with a porous material.

25. The bipolar membrane cartridge of claim 24, wherein: the porous material is one or more of activated carbon, carbon black, carbon nanotubes, graphite, carbon fibers, carbon cloth, carbon aerogel, metal powder, metal oxides and conductive polymers.

26. The bipolar membrane cartridge of claim 24, wherein: the porous electrode is also provided with a current collector which is laminated with the porous material.

27. The bipolar membrane cartridge of claim 24, wherein: the porous electrode is also provided with an ion exchange membrane, and the porous material and the ion exchange membrane are arranged in a stacked mode.

28. A roll-type bipolar membrane electrodeionization device is characterized in that: a bipolar membrane cartridge according to any one of claims 1 to 27.