CN116216995A

CN116216995A - Desulfurization wastewater treatment system

Info

Publication number: CN116216995A
Application number: CN202310264960.8A
Authority: CN
Inventors: 杨东昱; 崔德圣; 梁宵; 岳鹏飞; 庞晓辰; 刘进; 李宏秀; 许强; 秦树篷
Original assignee: Huadian Water Engineering Co ltd
Current assignee: Huadian Water Engineering Co ltd
Priority date: 2023-03-17
Filing date: 2023-03-17
Publication date: 2023-06-06

Abstract

The invention relates to a desulfurization wastewater treatment system, comprising: the flow electrode electro-adsorption module comprises a desulfurization wastewater inlet, a first brine outlet, a first flow electrode outlet and a first flow electrode inlet; the container comprises a first container inlet, a second container inlet, a first container outlet and a second container outlet, wherein the first container inlet is connected with the first flowing electrode outlet, and the first container outlet is connected with the first flowing electrode inlet; the flowing electrode electrodialysis module comprises a second flowing electrode inlet, a second brine outlet and a second flowing electrode outlet, wherein the second flowing electrode inlet is connected with the second container outlet, and the second flowing electrode outlet is connected with the second container inlet; the bipolar membrane electrodialysis module comprises a second brine inlet, a desalted liquid outlet, an acid liquid outlet and an alkali liquid outlet, wherein the second brine outlet is connected with the second brine inlet. The desulfurization wastewater treatment system can fully utilize ionic salt in desulfurization wastewater, has small solid waste production amount and can save energy.

Description

Desulfurization wastewater treatment system

Technical Field

The invention relates to the technical field of industrial wastewater treatment systems, in particular to a desulfurization wastewater treatment system.

Background

The most of coal-fired power plants in China use wet desulfurization, the amount of the generated desulfurization wastewater is large, the desulfurization wastewater is often used as tail end wastewater for cascade utilization of thermal power plant wastewater, and the water quality is extremely complex. The pollutants mainly comprise suspended matters, hardness, soluble salts, fluorides, heavy metal substances and the like, and along with the increasingly strict environmental protection requirements, the treatment of desulfurization wastewater gradually progresses from standard discharge to wastewater zero discharge technology.

In the prior desulfurization wastewater zero discharge technology, the desulfurization wastewater is usually treated by the following steps ofThree processes are performed, namely pretreatment, concentration and evaporative crystallization. The pretreatment mainly reduces the hardness and alkalinity in the desulfurization wastewater; concentrating mainly to reduce desulfurization wastewater to generate usable water and concentrated water; the concentrated water passes through a crystallizer to form salt which is then recycled or buried. However, the desulfurization wastewater contains a large amount of SO ₄ ^2- 、Ca ²⁺ 、Na ⁺ And Cl ^- Etc. SO (SO) ₄ ^2- And Ca ²⁺ The gypsum is incompletely precipitated, and if a large amount of medicaments are used for precipitation, energy waste and generation of a large amount of solid wastes can be caused. If flue gas evaporation technology is used, na ⁺ And Cl ^- When the salt obtained by concentrating and crystallizing is also present in part of the mixed salt, the purity is insufficient, and the sale of the salt is affected. Thus the current desulfurization wastewater treatment mode causes SO ₄ ^2- 、Ca ²⁺ 、Na ⁺ And Cl ^- The waste of the desulfurization waste water with small medicine consumption, low energy consumption, low investment and high resource utilization rate is developed, and the desulfurization waste water zero discharge technology is a problem to be solved in the environmental protection field of the thermal power plant at present.

Disclosure of Invention

Therefore, the invention aims to solve the technical problems of the prior art such as SO caused by the desulfurization waste water treatment method ₄ ^2- 、Ca ²⁺ 、Na ⁺ And Cl ^- The defects of large waste, large solid waste production, high energy consumption and the like, thereby providing a method capable of fully utilizing SO in desulfurization wastewater ₄ ^2- 、Ca ²⁺ 、Na ⁺ And Cl ^- The desulfurization wastewater treatment system has small solid waste production amount, small medicine consumption and low energy consumption.

In order to solve the above problems, the present invention provides a desulfurization wastewater treatment system including a flow electrode electro-adsorption module including a desulfurization wastewater inlet, a first brine outlet, a first flow electrode outlet, and a first flow electrode inlet; the container comprises a first container inlet, a second container inlet, a first container outlet and a second container outlet, wherein the first container inlet is connected with the first flowing electrode outlet, and the first container outlet is connected with the first flowing electrode inlet; the mobile electrode electrodialysis module comprises a second mobile electrode inlet, a second brine outlet and a second mobile electrode outlet, wherein the second mobile electrode inlet is connected with the second container outlet, and the second mobile electrode outlet is connected with the second container inlet; the bipolar membrane electrodialysis module comprises a second brine inlet, a desalted liquid outlet, an acid liquid outlet and an alkali liquid outlet, wherein the second brine outlet is connected with the second brine inlet.

Further, the flow electrode electroadsorption module comprises:

a housing;

a water distribution chamber formed at the bottom of the housing;

the anode electric adsorption chamber and the cathode electric adsorption chamber are arranged in the shell and respectively paved on two sides of the shell, the anode electric adsorption chamber is connected with the positive electrode of the power supply, the cathode electric adsorption chamber is connected with the negative electrode of the power supply, and the anode electric adsorption chamber and the cathode electric adsorption chamber are communicated with the outlet of the first movable electrode;

and the plurality of desalting units are arranged between the anode electric adsorption chamber and the cathode electric adsorption chamber and are spaced from each other, the bottoms of the desalting units are communicated with the water distribution chamber, and the upper ends of the desalting units are communicated with the first brine outlet.

Further, the side wall of the desalination unit facing the anode electro-adsorption chamber side comprises at least two first permeable baffles and a first monovalent selective anion exchange membrane clamped between the first permeable baffles, the side of the desalination unit facing the cathode electro-adsorption chamber comprises at least two first permeable baffles and a first monovalent selective cation exchange membrane clamped between the first permeable baffles, a water passing channel is formed between the side wall of the desalination unit facing the anode electro-adsorption chamber side and the side wall of the desalination unit facing the cathode electro-adsorption chamber side, the bottom of the water passing channel is communicated with the water distribution chamber, and the upper end of the water passing channel is communicated with a first brine outlet.

Further, the anode electro-adsorption chamber includes:

a second water permeable separator disposed within the housing adapted to separate the flow electrode from the desulfurization wastewater;

the metal woven electrode is arranged between the second water-permeable partition plate and the shell, paved on the shell and/or the second water-permeable partition plate and suitable for being connected with the positive electrode of the power supply;

a flow electrode formed within the metal braided electrode;

the cathodic electro-adsorption chamber comprises:

the metal woven electrode is arranged between the second water-permeable partition plate and the shell, paved on the shell and/or the second water-permeable partition plate and suitable for being connected with the negative electrode of the power supply;

a flow electrode formed within the metal braided electrode.

Further, the flow electrode electroadsorption module further comprises:

the cleaning port penetrates through the water distribution chamber and is communicated with the interior of the shell, and one side, far away from the shell, of the cleaning port is suitable for being connected with cleaning liquid;

and the drain outlet penetrates through the water distribution chamber and is communicated with the inside of the shell.

Further, the flow electrode electrodialysis module includes:

the first anode plate and the first cathode plate are arranged in parallel, the first anode plate is suitable for being connected with the positive electrode of the power supply, and the first cathode plate is suitable for being connected with the negative electrode of the power supply;

At least one second cation exchange membrane disposed between the first anode plate and the first cathode plate;

the second anion exchange membranes are arranged between the first anode plate and the first cathode plate and are staggered with the second cation exchange membranes, the second mobile electrode inlets are formed at the liquid inlet end of the mobile electrode electrodialysis module and are positioned between at least one group of second anion exchange membranes and the second cation exchange membranes, the second mobile electrode outlets are formed at the liquid outlet end of the mobile electrode electrodialysis module and are positioned between at least one group of second anion exchange membranes and the second cation exchange membranes, and the second brine outlets are formed at the liquid outlet end of the mobile electrode electrodialysis module and are staggered with the second mobile electrode outlets.

Further, the bipolar membrane electrodialysis module comprises a second anode plate, a first bipolar membrane, a third anion exchange membrane, a third cation exchange membrane, a second bipolar membrane and a second cathode plate which are sequentially arranged and spaced from each other, a second brine inlet is formed at the liquid inlet end of the bipolar membrane electrodialysis module and is positioned between the third anion exchange membrane and the third cation exchange membrane, a desalted liquid outlet is formed at the liquid outlet end of the bipolar membrane electrodialysis module and is positioned between the third anion exchange membrane and the third cation exchange membrane, an acid liquid outlet is formed at the liquid outlet end of the bipolar membrane electrodialysis module and is positioned between the first bipolar membrane and the third anion exchange membrane, and an alkali liquid outlet is formed at the liquid outlet end of the bipolar membrane electrodialysis module and is positioned between the third cation exchange membrane and the second bipolar membrane.

Further, the desulfurization wastewater treatment system comprises at least two bipolar membrane electrodialysis modules, wherein one group of bipolar membrane electrodialysis modules close to the flow electrode electrodialysis modules in the two adjacent groups of bipolar membrane electrodialysis modules is defined as a first bipolar membrane electrodialysis module, the other group of bipolar membrane electrodialysis modules is defined as a second bipolar membrane electrodialysis module, and a second brine inlet of the second bipolar membrane electrodialysis module is connected with a desalted liquid outlet of the first bipolar membrane electrodialysis module.

Further, the bipolar membrane electrodialysis module further includes:

an acid storage tank connected with the acid liquor outlet;

an alkali storage tank connected to the alkali outlet;

and the dilute brine storage tank is connected with the dilute brine outlet.

Further, the desulfurization wastewater treatment system further comprises a sedimentation filtration module, the sedimentation filtration module comprising:

the reaction chamber is suitable for receiving desulfurization wastewater, a stirring device is arranged in the reaction chamber, and a guide cylinder with two open ends is sleeved on the periphery of the stirring device;

the sedimentation chamber is communicated with the reaction chamber and is divided into at least two sedimentation partitions which are communicated with each other through at least one longitudinal partition plate;

the filtering chamber is communicated with the settling chamber, a filtering device is arranged in the filtering chamber, and the filtering chamber is communicated with the desulfurization waste water inlet of the flow electrode electric adsorption module.

Further, the alkali liquor outlet is connected with a reaction chamber of the sedimentation filtration module; and/or the number of the groups of groups,

the filtering chamber is connected with the desulfurization waste water inlet of the flow electrode electric adsorption module through a first pipeline, and the acid liquor outlet is connected with the first pipeline.

Further, the desulfurization wastewater treatment system also comprises a ceramic microfiltration device connected between the outlet of the filter chamber and the desulfurization wastewater inlet of the flow electrode electroadsorption module.

The invention has the following advantages:

the system for separating and treating wastewater comprises a flow electrode electro-adsorption module, a container, a flow electrode electrodialysis module and a bipolar membrane electrodialysis module. The flow electrode electro-adsorption module can receive desulfurization wastewater, and selectively adsorb Na in the desulfurization wastewater through the flow electrode and the desalination membrane unit ⁺ And Cl ^- To generate a solution with SO ₄ ^2- And Ca ²⁺ The first brine can be discharged through the first brine outlet for recycling to the desulfurization process, thereby avoiding SO ₄ ^2- And Ca ²⁺ Is a waste of (2). On one hand, the device realizes salt separation-desalination integration by coupling monovalent selective ion exchange membranes and electric adsorption, and greatly improves the energy utilization rate and the material utilization rate, and on the other hand, the desulfurization wastewater treatment system does not need Ca ²⁺ Precipitation is carried out, so that a large amount of a pharmaceutical agent such as Ca (OH) can be saved ₂ 、CaCO ₃ And the like, and reduces the generation of solid wastes, thereby saving the cost caused by the treatment of the solid wastes.

Carry Na ⁺ And Cl ^- Can enter the first container inlet of the container through the first container outlet and then enter the second flow electrode inlet of the flow electrode electrodialysis module through the first container outlet, and the flow electrode electrodialysis module can remove Na in the flow electrode ⁺ And Cl ^- To flow throughRegenerating the electrode and generating a catalyst containing Na ⁺ And Cl ^- Is a second brine of (a). The regenerated flowing electrode can return to the container through the second flowing electrode outlet and the second container inlet in sequence so as to be recycled by the flowing electrode electro-adsorption module.

The electroabsorption coupling flow electrode electrodialysis system of the flow electrode realizes the dynamic balance of the water-salt system in the industrial mode of feeding and discharging the desulfurization wastewater, so that the system has extremely strong impact load resistance, and the inspection and replacement of the flow electroabsorption material can be performed in a container.

The second brine can enter the bipolar membrane electrodialysis module through a second brine outlet, the bipolar membrane electrodialysis module being capable of producing the second brine as dilute brine, hydrochloric acid, and sodium hydroxide solution. The hydrochloric acid and sodium hydroxide solution can be recycled to various acid and alkali utilization points of the thermal power plant, such as acid and alkali dosing, raw water pretreatment dosing, boiler makeup water cleaning dosing and the like in the system, and the dilute brine can be recycled to a boiler makeup water reverse osmosis system or spray dust suppression of a coal yard. In summary, the desulfurization wastewater treatment system of the invention can treat SO in desulfurization wastewater ₄ ^2- And Ca ²⁺ Recycled to the desulfurization system to form gypsum, na ⁺ And Cl ^- Can be prepared into dilute brine, hydrochloric acid and sodium hydroxide solution, thereby realizing the recycling of desulfurization wastewater, needing no additional softening agent, reducing the generation of solid waste and saving the cost caused by the treatment of the solid waste.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 shows a schematic diagram of a desulfurization wastewater treatment system in accordance with an embodiment of the present invention;

FIG. 2 is a flow electrode electroadsorption module of a desulfurization wastewater treatment system according to an embodiment of the present invention;

FIG. 3 is a top view of a flow electrode electroadsorption module of a desulfurization wastewater treatment system in accordance with an embodiment of the present invention;

FIG. 4 is a schematic illustration of a desalination module of a flow electrode electroadsorption module of a desulfurization wastewater treatment system in accordance with an embodiment of the present invention;

FIG. 5 is an anodic electro-adsorption chamber of a desulfurization wastewater treatment system according to an embodiment of the present invention;

FIG. 6 is a cross-sectional view of the anode electro-adsorption chamber shown in FIG. 5;

FIG. 7 is a flow electrode electrodialysis module of a desulfurization wastewater treatment system according to an embodiment of the invention;

FIG. 8 is a bipolar membrane electrodialysis module of a desulfurization wastewater treatment system according to an embodiment of the invention;

FIG. 9 is a sedimentation filtration module of a desulfurization wastewater treatment system according to an embodiment of the present invention.

Reference numerals illustrate:

1. a flow electrode electroadsorption module; 11. a housing; 111. a cleaning port; 112. a sewage outlet; 12. a water distribution chamber; 13. an anode electro-adsorption chamber; 131. a second water permeable separator; 132. a metal braided electrode; 14. a cathode electroadsorption chamber; 15. a desalination unit; 152. a first water permeable separator; 153. a first monovalent selective anion exchange membrane; 154. a first monovalent selective cation exchange membrane; 16. a desulfurization waste water inlet; 17. a first brine outlet; 18. a first flow electrode inlet; 19. a first flow electrode outlet; 2. a container; 21. a first vessel inlet; 22. a first container outlet; 23. a second vessel inlet; 24. a second vessel outlet; 3. a flow electrode electrodialysis module; 31. a first anode plate; 32. a first cathode plate; 33. a second anion exchange membrane; 34. a second cation exchange membrane; 35. a second flow electrode inlet; 36. a second brine outlet; 37. a second flow electrode outlet; 4. a bipolar membrane electrodialysis module; 41. a second anode plate; 42. a first bipolar membrane; 43. a third anion exchange membrane; 44. a third cation exchange membrane; 45. a second bipolar membrane; 46. a second cathode plate; 47. a second brine inlet; 48. a desalinated liquid outlet; 49. an acid liquor outlet; 410. an alkali liquor outlet; 5. a sedimentation filtration module; 51. a reaction chamber; 52. a stirring device; 53. a guide cylinder; 54. a settling chamber; 55. a filtering chamber; 6. ceramic microfiltration device.

Detailed Description

The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In addition, the technical features of the different embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.

FIG. 1 shows a schematic diagram of a desulfurization wastewater treatment system in accordance with an embodiment of the present invention. As shown in fig. 1, the present embodiment relates to a desulfurization wastewater treatment system, which comprises a flow electrode electro-adsorption module 1, a container 2, a flow electrode electrodialysis module 3 and a bipolar membrane electrodialysis module 4. Wherein the flow electrode electroadsorption module 1 comprises a desulfurization waste water inlet 16, a first brine outlet 17, a first flow electrode outlet 19 and a first flow electrode inlet 18. The vessel 2 comprises a first vessel inlet 21, a second vessel inlet 23, a first vessel outlet 22 and a second vessel outlet 24. The first reservoir inlet 21 is connected to the first flow electrode outlet 19. The first reservoir outlet 22 is connected to the first flow electrode inlet 18. The flow electrode electrodialysis module 3 comprises a second flow electrode inlet 35, a second brine outlet 36 and a second flow electrode outlet 37. The second flow electrode inlet 35 is connected to the second container outlet 24. The second flow electrode outlet 37 is connected to the second vessel inlet 23. The bipolar membrane electrodialysis module 4 comprises a second brine inlet 47, a desalted liquid outlet 48, an acid liquid outlet 49 and an alkaline liquid outlet 410, the second brine outlet 36 being connected to the second brine inlet 47.

The system for treating the detached wastewater of the embodiment comprises a flow electrode electro-adsorption module 1, a container 2, a flow electrode electrodialysis module 3 and a bipolar membrane electrodialysis module 4. The flow electrode electro-adsorption module 1 can receive desulfurization wastewater, and selectively adsorb Na in the desulfurization wastewater through the flow electrode and the desalination membrane unit thereof ⁺ And Cl ^- To generate a solution with SO ₄ ^2- And Ca ²⁺ The first brine can be discharged through the first brine outlet 17 to be recycled to the desulfurization process, thereby avoiding SO ₄ ^2- And Ca ²⁺ Is a waste of (2). On one hand, the device realizes salt separation-desalination integration by coupling monovalent selective ion exchange membranes and electric adsorption, and greatly improves the energy utilization rate and the material utilization rate, and on the other hand, the desulfurization wastewater treatment system of the embodiment does not need Ca ²⁺ Precipitation is carried out, so that a large amount of a pharmaceutical agent such as Ca (OH) can be saved ₂ 、CaCO ₃ And the like, and reduces the generation of solid wastes, thereby saving the cost caused by the treatment of the solid wastes.

Carry Na ⁺ And Cl ^- Flow of (2)The electrode can enter the first container inlet 21 of the container 2 through the first container outlet 19 and then enter the second flow electrode inlet 35 of the flow electrode electrodialysis module 3 through the first container outlet 22, and the flow electrode electrodialysis module 3 can remove Na in the flow electrode ⁺ And Cl ^- To regenerate the movable electrode and generate Na-containing material ⁺ And Cl ^- Is a second brine of (a). The regenerated flow electrode can be returned to the vessel 2 through the second flow electrode outlet 37 and the second vessel inlet 23 in sequence for recycling by the flow electrode electro-adsorption module 1.

The electroabsorption coupling flow electrode electrodialysis system of the flow electrode realizes the dynamic balance of the water-salt system in the industrial mode of feeding and discharging the desulfurization wastewater, so that the system has extremely strong impact load resistance, and the inspection and replacement of the flow electroabsorption material can be performed in the container 2.

The second brine can enter the bipolar membrane electrodialysis module 4 through the second brine outlet 36, and the bipolar membrane electrodialysis module 4 can prepare the second brine into dilute brine, hydrochloric acid and sodium hydroxide solution. The hydrochloric acid and sodium hydroxide solution can be recycled to various acid and alkali utilization points of the thermal power plant, such as acid and alkali dosing, raw water pretreatment dosing, boiler makeup water cleaning dosing and the like in the system, and the dilute brine can be recycled to a boiler makeup water reverse osmosis system or spray dust suppression of a coal yard. In summary, the desulfurization wastewater treatment system of the present embodiment can treat SO in desulfurization wastewater ₄ ^2- And Ca ²⁺ Recycled to the desulfurization system to form gypsum, na ⁺ And Cl ^- Can be prepared into dilute brine, hydrochloric acid and sodium hydroxide solution, thereby realizing the recycling of desulfurization wastewater, needing no additional softening agent, reducing the generation of solid waste and saving the cost caused by the treatment of the solid waste.

The flow electrode electro-adsorption module 1 may alternatively include an anode plate, an anion exchange membrane, a cation exchange membrane, and a cathode plate disposed in parallel in this order. The flow electrode is positioned between the anion exchange membrane and the cation exchange membrane, and the desulfurization wastewater is positioned between the anode plate and the anion exchange membrane, and between the cathode plate and the cation exchange membrane.

Preferably, as shown in fig. 2 and 3, in the present embodiment, the flow electrode electrosorption module 1 includes a housing 11, a water distribution chamber 12, an anode electrosorption chamber 13, a cathode electrosorption chamber 14, and a plurality of desalination units 15. The water distribution chamber 12 is formed at the bottom of the housing 11. The anode electro-adsorption chamber 13 and the cathode electro-adsorption chamber 14 are provided in the housing 11 and are respectively laid on both sides of the housing 11. The anode electro-adsorption chamber 13 is connected with the positive electrode of the power supply. The cathodic electrosorption chamber 14 is connected to the negative pole of the power supply. The anode electro-adsorption chamber 13 and the cathode electro-adsorption chamber 14 are in communication with a first flow electrode outlet 19. A plurality of desalination units 15 are disposed between the anode electro-adsorption chamber 13 and the cathode electro-adsorption chamber 14 and spaced apart from each other. The bottom of the desalination unit 15 is communicated with the water distribution chamber 12, and the upper end of the desalination unit 15 is communicated with the first brine outlet 17.

The flow electrode electro-adsorption module 1 of the embodiment modularizes the desalination units 15, and each desalination unit 15 is arranged in a staggered manner, so that the problems of small ion exchange membrane area, reduced desalination efficiency, serious membrane polarization and the like caused by insufficient ion transmission capacity due to a conventional membrane arrangement mode are avoided. The flow electrode electro-adsorption module 1 of the present embodiment increases the ion exchange membrane area, and due to the modular arrangement of the desalination unit 15, an operator can open the housing to withdraw the desalination unit 15 during maintenance and replacement, and the flow electrode electro-adsorption module 1 of the present embodiment facilitates replacement and maintenance of electro-adsorption equipment.

Specifically, the water distribution chamber 12 may be selected to include a partition for partitioning the water distribution chamber 12 from an upper space of the housing 11. The partition plate is provided with a plurality of water outlets matched with the cross section of the desalination unit 15, and the bottoms of the desalination modules are in sealing connection with the water outlets in a one-to-one correspondence manner.

The size of the desalination unit 15 can be adaptively set according to the flow rate, salt content, and size of the housing 11 of the desulfurization waste water. Preferably, in this embodiment, the desalination unit 15 is 10 cm long, 2.5 cm wide and 100 cm high. The areas of the first monovalent selective anion exchange membrane 153 and the first monovalent selective cation exchange membrane 154 can be calculated from the desalination amount. First monovalent selective anion exchange The current density of the membrane 153 and the first monovalent selective cation exchange membrane 154 may be selected to be in the range of 280 to 360A/m ² Between them.

As shown in fig. 4, in the present embodiment, the side wall of the desalination unit 15 on the side facing the anode electro-adsorption chamber 13 includes at least two first water permeable separator plates 152 arranged in a stacked manner and a first monovalent selective anion exchange membrane 153 interposed between the first water permeable separator plates 152. The side of the desalination unit 15 facing the cathode electro-adsorption chamber 14 includes at least two first water permeable separators 152 and a first monovalent selective cation exchange membrane 154 sandwiched between the first water permeable separators 152. A water passage is formed between the side wall facing the anode electro-adsorption chamber 13 side and the side wall facing the cathode electro-adsorption chamber 14 side. The bottom of the water passing channel is communicated with the water distribution chamber 12, and the upper end of the water passing channel is communicated with the first brine outlet 17. The other two side walls of the water passage may alternatively be composed of watertight partitions, and in one embodiment, the desalination unit 15 has a desalination unit housing, and one side wall of the desalination unit housing facing the anode electro-adsorption chamber 13 and one side wall facing the cathode electro-adsorption chamber 14 are made of a watertight partition sandwiching an ion exchange membrane. The other two side walls of the desalination unit housing are composed of watertight partitions. The material of the separator is preferably insulating polypropylene.

The flow rate of the desulfurization waste water in the desalting unit 15 is preferably in the range of 6 to 8cm/s, and the calcium sulfate structure can be prevented. Cl ^- And Na (Na) ⁺ Respectively penetrate the membrane and are transferred into the flowing electrode under the action of electric field force SO ₄ ^2- And Ca ²⁺ Is blocked from flowing out of the upper portion of the desalination unit 15, recycled to the desulfurization process tank and continued for desulfurization to form gypsum. The process is completed as salt and SO ₄ ^2- And Ca ²⁺ Can be reused. As the content of sulfate and sodium chloride in the desulfurization wastewater is almost the same, the osmotic pressure at two sides of the membrane is greatly reduced, and the service life of the membrane can be prolonged.

As shown in fig. 5 and 6, in the present embodiment, the anode electro-adsorption chamber 13 preferably includes a second water-permeable separator 131, a metal braid electrode 132, and a flow electrode. A second water permeable separator 131 is provided within the housing 11 and is adapted to separate the flow electrode from the desulfurization waste water such that a majority of the flow electrode is confined within the anode electro-adsorption chamber 13. The metal braided electrode 132 is disposed between the second water permeable separator 131 and the housing 11, and is laid on the housing 11 and/or the second water permeable separator 131, and is adapted to be connected to the positive electrode of the power supply. The flow electrode is formed within a metal braided electrode 132.

The cathode electroadsorption chamber 14 includes a second water permeable separator 131, a metal woven electrode 132, and a flow electrode. Wherein a second water permeable separator 131 is provided within the housing 11, adapted to separate the flow electrode from the desulfurization waste water such that a majority of the flow electrode is confined within the cathodic electrosorption chamber 14. The metal braided electrode 132 is disposed between the second water-permeable separator 131 and the casing 11, and is laid on the casing 11 and/or the second water-permeable separator 131, and is adapted to be connected to the negative electrode of the power supply. The flow electrode is formed within a metal braided electrode 132.

The second water permeable separator 131 can separate the electric adsorption chamber from the desalination unit 15, and the pore diameter of the water permeable separator is preferably 0.5mm, so that most of the activated carbon can be restrained in the cathode electric adsorption chamber 14 and the anode electric adsorption chamber 13, so that the ion exchange membrane is prevented from being polluted by the excessive concentration of the activated carbon, and the ion transmission and the water exchange are not affected. In addition, the permeable partition plate can be convenient for overhauling the electric adsorption chamber, and an operator can finish overhauling by opening the shell 11 and drawing out the electric adsorption chamber. The metal braided electrode 132 is preferably, but not limited to, a titanium ruthenium coated electrode having strong corrosion resistance, which has a mesh structure, which can increase the contact area with the flowing electrode, and has higher conductivity efficiency. The flowing electrode is preferably but not limited to being prepared by granular active carbon, acetylene black and an auxiliary agent in NaCl solution, wherein the size of the active carbon is between 10 and 50 mu m, and the flowing electrode has good adsorption performance and certain mechanical strength. The specific manner in which the flow electrode is formulated is well known to those skilled in the art and will not be described in detail herein. The voltage difference between the anode electro-adsorption chamber 13 and the cathode electro-adsorption chamber 14 is preferably maintained in the range of 1.0-1.5V.

The flow electrode can enter the container 2 through the first flow electrode outlet 19 and the first container inlet 21 after adsorption saturation, and the flow electrode flowing out of the cathode electric adsorption chamber 14 and the anode electric adsorption chamber 13 is mixed and enters the electrode electrodialysis unit. Preferably, a peristaltic pump is provided between the container 2 and the flow electrode electrodialysis module 3. The peristaltic pump is capable of driving the flow electrode within the container 2 into the flow electrode electrodialysis module.

Preferably, in the present embodiment, the flow electrode electro-adsorption module 1 further includes a cleaning port 111 and a drain port 112. Wherein a cleaning port 111 penetrates the water distribution chamber 12 and communicates with the inside of the housing 11, and a side of the cleaning port 111 away from the housing 11 is adapted to be connected with a cleaning liquid. A drain 112 passes through the water distribution chamber 12 and communicates with the interior of the housing 11. After the flowing electrode electro-adsorption module 1 is operated for a period of time, the cleaning port 111 can spray the cleaning liquid to clean the desalination unit 15 and electro-adsorption chamber inside the housing 11, and the cleaning liquid can flow out through the drain port 112. Preferably, the cleaning solution is selected from acid and alkali generated by bipolar membrane electrodialysis, and acid with the concentration of 3% and alkali liquor with the concentration of 1% are prepared. The cleaning is performed according to the sequence of water washing, acid washing, water washing, alkali washing, water washing, acid washing and water washing, inorganic scale generated by high-valence salt can be removed by acid washing, organic scale can be removed by alkali washing, and the acid and alkali generated by the bipolar membrane electrodialysis module 4 are used, so that the cost and the expense of cleaning are saved.

In this embodiment, as shown in fig. 7, the flow electrode electrodialysis module 3 includes a first anode plate 31, a first cathode plate 32, at least one second anion exchange membrane 33, and at least one second cation exchange membrane 34. Wherein the first anode plate 31 and the first cathode plate 32 are disposed parallel to each other. The first anode plate 31 is adapted to be connected to the positive pole of a power source and the first cathode plate 32 is adapted to be connected to the negative pole of the power source. At least one second anion exchange membrane 33 is disposed between the first anode plate 31 and the first cathode plate 32. At least one second cation exchange membrane 34 is disposed between the first anode plate 31 and the first cathode plate 32 and is staggered with the second cation exchange membrane 34, a second mobile electrode inlet 35 is formed at the liquid inlet end of the mobile electrode electrodialysis module 3 and is located between at least one group of second anion exchange membranes 33 and the second cation exchange membranes 34, and a second mobile electrode outlet 37 is formed at the liquid outlet end of the mobile electrode electrodialysis module 3 and is located between at least one group of second anion exchange membranes 33 and the second cation exchange membranes 34. The second brine outlet 36 is formed at the liquid outlet end of the flow electrode electrodialysis module 3 and is arranged in a staggered manner with respect to the second flow electrode outlet 37.

The water inlet channels of the second anion exchange membrane 33 and the second cation exchange membrane 34 are preferably greater than 5mm to prevent clogging of the activated carbon. The ion exchange membrane of the flow electrode electrodialysis module 3 has strong wear resistance and certain pollution resistance. The flow electrode is rapidly desalted in the flow electrode electrodialysis module 3 to realize the regeneration of the flow electrode, the regenerated flow electrode enters the container 2 and is peristaltic pumped into the flow electrode electrodialysis module to be adsorbed again, so that the balance of adsorption and desorption of the flow electrode in the system is realized, and the circulation use of the flow electrode is realized. The flow electrode electrodialysis module may optionally further comprise a concentrate tank, a pole tank, and a control tank. Wherein the concentrate tank is adapted to hold liquid discharged from the second brine outlet 36. The anode water tank is used for containing anode liquid and circulating the anode liquid therein, and the cathode water tank is used for containing cathode liquid and circulating the cathode liquid therein.

In this embodiment, as shown in fig. 8, the bipolar membrane electrodialysis module 4 includes a second anode plate 41, a first bipolar membrane 42, a third anion exchange membrane 43, a third cation exchange membrane 44, a second bipolar membrane 45, and a second cathode plate 46, which are disposed in this order and spaced apart from each other, a second brine inlet 47 is formed at the liquid inlet end of the bipolar membrane electrodialysis module 4 between the third anion exchange membrane 43 and the third cation exchange membrane 44. A desalted liquid outlet 48 is formed at the liquid outlet end of the bipolar membrane electrodialysis module 4 and is located between the third anion exchange membrane 43 and the third cation exchange membrane 44. An acid outlet 49 is formed at the liquid outlet end of the bipolar membrane electrodialysis module 4 and is located between the first bipolar membrane 42 and the third anion exchange membrane 43. A lye outlet 410 is formed at the liquid outlet end of the bipolar membrane electrodialysis module 4 and is located between the third cation exchange membrane 44 and the second bipolar membrane 45.

The desulfurization wastewater treatment system of this embodiment may optionally include a set of bipolar membrane electrodialysis modules 4. Preferably, in the present embodiment, the desulfurization-wastewater treatment system includes at least two bipolar membrane electrodialysis modules 4, and one set of bipolar membrane electrodialysis modules 4 adjacent to the flow electrode electrodialysis module among the two adjacent sets of bipolar membrane electrodialysis modules 4 is defined as a first bipolar membrane electrodialysis module 4, and the other set is defined as a second bipolar membrane electrodialysis module 4. The second brine inlet 47 of the second bipolar membrane electrodialysis module 4 is connected to the desalted liquid outlet 48 of the first bipolar membrane electrodialysis module 4. Can promote the recycling effect of desulfurization wastewater. For example, in this embodiment, the desulfurization wastewater treatment system includes three bipolar membrane electrodialysis modules 4 connected in series with each other.

The first group of bipolar membrane electrodialysis modules 4 can realize 70% salt utilization, the second group of bipolar membrane electrodialysis modules 4 can realize 65% salt utilization, the third group of bipolar membrane electrodialysis modules can realize 60% salt utilization, and finally more than 95% of salt is prepared into acid and alkali, the concentration of the prepared acid and alkali is about 1.4mol/L, and the purity is about 98%. Hydrochloric acid and sodium hydroxide solution can be recycled to various acid and alkali utilization points of the thermal power plant, such as acid and alkali dosing, raw water pretreatment dosing, boiler makeup water cleaning dosing and the like in the system, so that the pretreatment cost of the thermal power plant makeup water is greatly reduced. The dilute brine can be reused in a boiler makeup water reverse osmosis system or sprayed dust suppression of a coal yard. In addition, the bipolar membrane electrodialysis module 4 is used for separating salt in the desulfurization wastewater, and compared with the modes such as concentration crystallization and the like in the prior art, the method has the advantages of short process chain and less impurity salt in the generated salt.

In this embodiment, the bipolar membrane electrodialysis module 4 further comprises an acid tank, a base tank and a weak brine tank. Wherein the acid reservoir is connected to an acid outlet 49. The base reservoir is connected to the base outlet 410. The dilute brine storage tank is connected to the dilute brine outlet 48.

In this embodiment, as shown in fig. 9, the desulfurization wastewater treatment system preferably further includes a sedimentation filtration module 5. The sedimentation filtration module 5 comprises a reaction chamber 51, a sedimentation chamber 54 and a filtration chamber 55. The reaction chamber 51 is adapted to receive desulfurization waste water. A stirring device 52 is provided in the reaction chamber 51. The periphery of the stirring device 52 is sleeved with a guide cylinder 53 with two open ends. Settling chamber 54 is in communication with reaction chamber 51. The interior of settling chamber 54 is divided into at least two settling compartments in communication with each other by at least one longitudinal partition. The filtering chamber 55 is communicated with the settling chamber 54, a filtering device is arranged in the filtering chamber 55, and the filtering chamber 55 is communicated with the desulfurization waste water inlet 16 of the flow electrode electric adsorption module 1.

The sedimentation filter module 5 of the embodiment performs targeted treatment on the characteristics of the desulfurization wastewater, and by arranging the guide cylinder 53 on the periphery of the stirring device 52, vortex is formed in the guide cylinder 53 along with stirring, so that the mixing degree of the desulfurization wastewater and the absorbent is enhanced; multistage sedimentation of the desulfurization wastewater is realized through a plurality of sedimentation partitions formed by the longitudinal partition plates. Compared with the traditional triple box, the triple box has the advantages of simple structure, strong mixing capability and good separation effect. Preferably, a high-efficiency composite desulfurization wastewater treatment agent and NaOH are added into the sedimentation filtration module 5 of the embodiment to replace traditional flocculating agents, coagulant aids, organic sulfur, lime or sodium carbonate and other agents.

The agent comprises diatomite, zeolite molecular sieve, active carbon, bentonite and other inorganic materials. Compared with the traditional medicament, the method has the advantages of lower operation cost, simple operation, high water outlet stability, halving of sludge amount and the like, can be perfectly abutted with the follow-up flow electrode electro-adsorption module 1, the flow electrode electro-osmosis module 3 and the bipolar membrane electro-osmosis module 4, can not influence the membrane, can especially solve the problems of COD, heavy metals, fluoride and membrane blockage, and can also shorten flocculation time, so that the flocculation time is reduced from the traditional time of more than or equal to 30min to 5-10min, and the sedimentation time is reduced from the traditional time of more than or equal to 6 hours to 1-2 hours. The device volume and the floor space can be greatly reduced. And because lime is not needed to be added, the generated mud amount is reduced by about half, and the mud treatment cost is saved. The separated and clarified desulfurization waste water is filtered in a simple manner in a filter chamber 55 to remove suspended substances and the like. And adding HCl into the water outlet to adjust the PH to 7.

The concentration of F ions in the treated wastewater is below 5 mg/L. Adding NaOH to adjust pH to 11, removing a large amount of magnesium ions, and controlling magnesium ion concentration below 200Mg/L to form Mg (OH) ₂ And then the high-efficiency composite medicament is adsorbed and coprecipitated, so that a good removing effect can be achieved.

Preferably, in this embodiment, the lye outlet 410 is connected to the reaction chamber 51 of the sedimentation filtration module 5. The filter chamber 55 is connected to the desulfurization waste water inlet 16 of the flow electrode electroadsorption module 1 through a first pipeline, and the acid liquor outlet 49 is connected to the first pipeline. This allows the lye produced by the bipolar membrane electrodialysis module 4 to be fed into the reaction chamber 51 and used to adjust the PH of the desulfurization wastewater to 10.5 and to precipitate magnesium ions. The acid liquor generated by the bipolar membrane electrodialysis module 4 can be introduced into the first pipeline to adjust the pH value of the desulfurization wastewater, so that the product of the bipolar membrane electrodialysis module 4 is fully utilized, and the dosing cost is greatly reduced.

In this embodiment, the desulfurization waste water treatment system further comprises a ceramic microfiltration device 6 connected between the outlet of the filtration chamber 55 and the desulfurization waste water inlet 16 of the flow electrode electroadsorption module 1. The wastewater after sedimentation and filtration still contains a large amount of inorganic salts and suspended matters, and has high hardness, so that the chemical property, mechanical strength and service life of the conventional organic microfiltration equipment are difficult to meet the microfiltration requirements of the desulfurization wastewater. The desulfurization wastewater treatment system of this embodiment adopts ceramic microfiltration device 6 to filter desulfurization wastewater, and its mechanical strength is big, the flux is high, be difficult for blockking up, long service life, easy maintenance can satisfy desulfurization wastewater's filtration demand, and domestic product can satisfy the operation requirement, can reduce equipment cost.

Preferably, in the present embodiment, the ceramic microfiltration device 6 comprises a feed pump, a ceramic microfiltration membrane device and a cleaning system. The ceramic microfiltration membrane is preferably a microfiltration membrane with large aperture, the aperture is selected to be in the range of 0.1-1 μm, the ceramic membrane is preferably a flat ceramic membrane, and the ceramic material is Al ₂ O ₃ Cross-flow filtration is selected. The design flux is 300-500L/m ² Between h. The cleaning system is preferably in communication with the acid and base reservoirs of the bipolar membrane electrodialysis module 4, and is capable of acid and base washing the microfiltration desulfurized wastewater with the product of the bipolar membrane electrodialysis module 4. After microfiltration, suspended matters of the wastewater are smaller than 1NTU, so that the water inlet requirement of the ion exchange membrane is met.

An example of the desulfurization wastewater treatment system of the present invention for treating desulfurization wastewater will be described below:

a certain 2X 35 kilowatt cogeneration coal-fired power plant adopts a limestone-gypsum wet desulfurization process, is arranged in one furnace and one tower, has about 10t/h of desulfurization wastewater volume, and is 15m in accordance with ³ And (3) designing the wastewater amount. The desulfurization wastewater treatment system is used for treating desulfurization wastewater, and the water quality and water quantity of each stage are as follows:

each stage	Raw water	After pretreatment	First brine	Second salt water	Light brine
						Water quantity/m ³	15	15	13.5	1.35	0.55
TDS	35000	35000	18900	200000	8400
						SS	25100	5	6	0	0
Ca ₂ ⁺	1900	1900	2110	0	0
						Mg ₂ ⁺	3614	200	230	0	0
Na ⁺	7524	7524	500	78630	1817
						Cl ^-	12500	12500	1760	121300	5097
F ^-	80	0	0	0	0
						SO ₄ ^2-	8300	8300	9200	200	0

Note that: the ion units are mg/L

As shown in the table, the desulfurization wastewater treatment system of the embodiment of the invention has the direct recycling rate of desulfurization wastewater up to 90 percent, ca ₂ ⁺ ，Na ⁺ ，SO ₄ ^2- And Cl ^- The recycling rate of the plasma salt is up to more than 95%, and the recycling level is extremely high. In terms of investment and operating costs, despite the high cost of ceramic microfiltration device 6 and bipolar membrane electrodialysis module 4, compared to the zero emission technology currently in common use, the total investment is still slightly lower than in the prior art, due to its ability to save more than 50% of the floor space and civil cost of the system.

At the running cost, the medicament cost is about 9 yuan/m ³ (containing special defluorinating agent), the running power consumption of the system is about 46.3 kW.h/m ³ Most of the electricity consumption is that of the bipolar membrane electrodialysis module 4, and the electricity price of the power plant is 0.4 yuan kW.h/m ³ Calculating the operation cost to be 27.5 yuan/m ³ And produce 3m ³ The acid and the alkali with the mol/L of about 1.4 are directly recycled into the dosing of the water pretreatment high-density clarifier in the power plant, and the cost of the alkali is directly saved by 336 yuan/h (the finished alkali is 2000 yuan/ton), the cost of the acid is saved by 148 yuan/h (the 31 percent industrial hydrochloric acid is 300 yuan/ton), so that the net benefit of the power plant is 456.5 yuan/h, and good economic benefit is obtained. And no generation of mixed salt waste, realizes the coal-fired power plant The zero emission of desulfurization wastewater and the reutilization of mixed salt resources can obtain better environmental protection and ecological benefits.

In summary, the desulfurization wastewater treatment system of the present invention has the following advantages:

1. the desulfurization wastewater treatment system of the invention can realize 90% recycling of desulfurization wastewater on the basis of realizing zero emission of desulfurization wastewater, and prepares mixed salt wastewater into acid and alkali, naCl-CaSO ₄ The material utilization rate is up to more than 95%.

2. The desulfurization wastewater treatment system uses the desulfurization wastewater integrated reaction and ceramic microfiltration device 6, and can complete pretreatment of desulfurization wastewater without softening by a large amount of agents, thereby saving investment and operation cost.

3. The desulfurization wastewater treatment system can realize salt separation and concentration of desulfurization wastewater with low energy consumption, and can quickly regenerate mobile activated carbon by using mobile electrode electrodialysis. By using the system, the occupied area is small, the operation is continuous, the energy utilization rate is high, the maintenance aspect and the intelligent degree are high, and the current requirements of the intelligent power plant can be met.

4. The multistage bipolar membrane electrodialysis modules 4 are connected in series, so that the utilization rate of salt is greatly improved, the generated acid and alkali are directly reused in a power plant, and the residual trace fresh brine is subjected to reverse osmosis or is used for spraying in a coal yard, so that non-negligible economic benefit is generated.

It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.

Claims

1. A desulfurization wastewater treatment system, comprising:

a flow electrode electroadsorption module (1) comprising a desulfurization wastewater inlet (16), a first brine outlet (17), a first flow electrode outlet (19) and a first flow electrode inlet (18);

a vessel (2) comprising a first vessel inlet (21), a second vessel inlet (23), a first vessel outlet (22) and a second vessel outlet (24), said first vessel inlet (21) being connected to said first flow electrode outlet (19), said first vessel outlet (22) being connected to said first flow electrode inlet (18);

a flow electrode electrodialysis module (3) comprising a second flow electrode inlet (35), a second brine outlet (36) and a second flow electrode outlet (37), the second flow electrode inlet (35) being connected to the second vessel outlet (24), the second flow electrode outlet (37) being connected to the second vessel inlet (23);

A bipolar membrane electrodialysis module (4) comprising a second brine inlet (47), a desalinated liquid outlet (48), an acid liquid outlet (49) and an alkaline liquid outlet (410), the second brine outlet (36) being connected to the second brine inlet (47).

2. The desulfurization wastewater treatment system according to claim 1, characterized in that the flow electrode electrosorption module (1) comprises:

a housing (11);

a water distribution chamber (12) formed at the bottom of the housing (11);

an anode electro-adsorption chamber (13) and a cathode electro-adsorption chamber (14) which are arranged in the shell (11) and are respectively paved on two sides of the shell (11), wherein the anode electro-adsorption chamber (13) is connected with the positive electrode of a power supply, the cathode electro-adsorption chamber (14) is connected with the negative electrode of the power supply, and the anode electro-adsorption chamber (13) and the cathode electro-adsorption chamber (14) are communicated with the first flowing electrode outlet (19);

a plurality of desalination units (15), a plurality of desalination units (15) are arranged between the anode electric adsorption chamber (13) and the cathode electric adsorption chamber (14) and are separated from each other, the bottom of the desalination units (15) is communicated with the water distribution chamber (12), and the upper end of the desalination units (15) is communicated with the first brine outlet (17).

3. The desulfurization wastewater treatment system according to claim 2, wherein the side wall of the desalination unit (15) facing the anode electro-adsorption chamber (13) comprises at least two first water permeable partition plates (152) and a first monovalent selective anion exchange membrane (153) sandwiched between the first water permeable partition plates (152) which are stacked, the side of the desalination unit (15) facing the cathode electro-adsorption chamber (14) comprises at least two first water permeable partition plates (152) and a first monovalent selective cation exchange membrane (154) sandwiched between the first water permeable partition plates (152), a water passage is formed between the side wall of the desalination unit (15) facing the anode electro-adsorption chamber (13) and the side wall facing the cathode electro-adsorption chamber (14), the bottom of the water passage is communicated with the water distribution chamber (12), and the upper end of the water passage is communicated with the first brine outlet (17).

4. The desulfurization wastewater treatment system according to claim 2, wherein the anodic electro-adsorption chamber (13) comprises:

a second water-permeable separator (131) disposed within the housing (11) and adapted to separate the flow electrode from the desulfurization wastewater;

a metal braided electrode (132) which is arranged between the second water-permeable separator (131) and the housing (11) and is laid on the housing (11) and/or the second water-permeable separator (131) and is suitable for being connected with the positive electrode of the power supply;

a flow electrode formed within the metal braided electrode (132);

the cathodic electrosorption chamber (14) comprises:

a metal braided electrode (132) which is arranged between the second water-permeable separator (131) and the housing (11) and is laid on the housing (11) and/or the second water-permeable separator (131) and is suitable for being connected with the negative electrode of the power supply;

a flow electrode formed within the metal braided electrode (132).

5. The desulfurization wastewater treatment system according to claim 2, wherein the flow electrode electrosorption module (1) further comprises:

A cleaning port (111) penetrating through the water distribution chamber (12) and communicating with the inside of the housing (11), a side of the cleaning port (111) away from the housing (11) being adapted to be connected with a cleaning liquid;

a drain (112) passing through the water distribution chamber (12) and communicating with the interior of the housing (11).

6. The desulphurised wastewater treatment system according to any of claims 1-5, characterized in that the flow electrode electrodialysis module (3) comprises:

the first anode plate (31) and the first cathode plate (32), the first anode plate (31) and the first cathode plate (32) are arranged in parallel, the first anode plate (31) is suitable for being connected with the positive electrode of a power supply, and the first cathode plate (32) is suitable for being connected with the negative electrode of the power supply;

at least one second anion exchange membrane (33) disposed between the first anode plate (31) and the first cathode plate (32);

the second cation exchange membranes (34) are arranged between the first anode plate (31) and the first cathode plate (32) and are staggered with the second cation exchange membranes (34), the second mobile electrode inlets (35) are formed at the liquid inlet ends of the mobile electrode electrodialysis modules (3) and are positioned between at least one group of the second anion exchange membranes (33) and the second cation exchange membranes (34), the second mobile electrode outlets (37) are formed at the liquid outlet ends of the mobile electrode electrodialysis modules (3) and are positioned between at least one group of the second anion exchange membranes (33) and the second cation exchange membranes (34), and the second brine outlets (36) are formed at the liquid outlet ends of the mobile electrode electrodialysis modules (3) and are staggered with the second mobile electrode outlets (37).

7. The desulfurization wastewater treatment system according to any one of claims 1-5, characterized in that the bipolar membrane electrodialysis module (4) comprises a second anode plate (41), a first bipolar membrane (42), a third anion exchange membrane (43), a third cation exchange membrane (44), a second bipolar membrane (45) and a second cathode plate (46) arranged in sequence and spaced apart from each other, the second brine inlet (47) being formed at the liquid inlet end of the bipolar membrane electrodialysis module (4) between the third anion exchange membrane (43) and the third cation exchange membrane (44), the desalted liquid outlet (48) being formed at the liquid outlet end of the bipolar membrane electrodialysis module (4) between the third anion exchange membrane (43) and the third cation exchange membrane (44), the acid liquid outlet (49) being formed at the liquid outlet end of the bipolar membrane electrodialysis module (4) between the first bipolar membrane (42) and the third anion exchange membrane (43), the outlet (48) being formed at the liquid outlet end of the bipolar membrane (4) between the bipolar membrane (45) and the third cation exchange membrane (44).

8. The desulfurization wastewater treatment system according to claim 7, characterized in that the desulfurization wastewater treatment system comprises at least two bipolar membrane electrodialysis modules (4), one bipolar membrane electrodialysis module (4) of the adjacent two bipolar membrane electrodialysis modules (4), which is close to the flow electrode electrodialysis module, being defined as a first bipolar membrane electrodialysis module (4), the other bipolar membrane electrodialysis module (4), and a second brine inlet (47) of the second bipolar membrane electrodialysis module (4) being connected to a desalinated liquid outlet (48) of the first bipolar membrane electrodialysis module (4).

9. The desulfurization wastewater treatment system according to claim 7, characterized in that the bipolar membrane electrodialysis module (4) further comprises:

an acid reservoir connected to the acid outlet (49);

an alkali storage tank connected to the alkali liquor outlet (410);

and a dilute brine storage tank connected with the dilute brine outlet (48).

10. The desulfurization wastewater treatment system according to any one of claims 1-5, further comprising a sedimentation filtration module (5), the sedimentation filtration module (5) comprising:

the desulfurization device comprises a reaction chamber (51), wherein the reaction chamber (51) is suitable for receiving desulfurization wastewater, a stirring device (52) is arranged in the reaction chamber (51), and a guide cylinder (53) with two open ends is sleeved on the periphery of the stirring device (52);

a settling chamber (54) in communication with the reaction chamber (51), the interior of the settling chamber (54) being divided into at least two settling compartments in communication with each other by at least one longitudinal partition;

the filtering chamber (55) is communicated with the sedimentation chamber (54), a filtering device is arranged in the filtering chamber (55), and the filtering chamber (55) is communicated with the desulfurization waste water inlet (16) of the flow electrode electric adsorption module (1).

11. The desulfurization wastewater treatment system according to claim 10, characterized in that the lye outlet (410) is connected to a reaction chamber (51) of the sedimentation filtration module (5); and/or the number of the groups of groups,

The filtering chamber (55) is connected with the desulfurization waste water inlet (16) of the flowing electrode electric adsorption module (1) through a first pipeline, and the acid liquor outlet (49) is connected with the first pipeline.

12. The desulfurization wastewater treatment system according to claim 10, further comprising a ceramic microfiltration device (6) connected between an outlet of the filter chamber (55) and a desulfurization wastewater inlet (16) of the flow electrode electroadsorption module (1).