A desulfurization wastewater treatment system

Abstract

The present invention relates to a desulfurization wastewater treatment system, comprising: a flow electrode electrosorption module, comprising a desulfurization wastewater inlet, a first salt water outlet, a first flow electrode outlet and a first flow electrode inlet; a container, comprising a first container inlet, a second container inlet, a first container outlet and a second container outlet, the first container inlet is connected to the first flow electrode outlet, and the first container outlet is connected to the first flow electrode inlet; a flow electrode electrodialysis module, comprising a second flow electrode inlet, a second salt water outlet and a second flow electrode outlet, the second flow electrode inlet is connected to the second container outlet, and the second flow electrode outlet is connected to the second container inlet; a bipolar membrane electrodialysis module, comprising a second salt water inlet, a desalinated liquid outlet, an acid outlet and an alkali liquid outlet, and the second salt water outlet is connected to the second salt water inlet. The desulfurization wastewater treatment system of the present invention can make full use of the ionic salts in the desulfurization wastewater, and the amount of solid waste generated is small, which can save energy.

Description

Technical Field

[0001] The invention relates to the technical field of industrial wastewater treatment systems, and in particular to a desulfurization wastewater treatment system. Background Art

[0002] Most of my country's coal-fired power plants use wet desulfurization, which produces a large amount of desulfurization wastewater. Desulfurization wastewater is often used as the terminal wastewater of the thermal power plant wastewater cascade utilization, and the water quality is extremely complex. Pollutants mainly include suspended solids, hardness, soluble salts, fluorides, and heavy metal substances. With the increasingly stringent environmental protection requirements, the treatment of desulfurization wastewater has gradually developed from standard discharge to zero wastewater discharge process.

[0003] The existing zero-emission technology for desulfurization wastewater usually goes through three processes, namely pretreatment, concentration and evaporation crystallization. Pretreatment is mainly to reduce the hardness and alkalinity in desulfurization wastewater; concentration is mainly to reduce the desulfurization wastewater to produce usable water and concentrated water; concentrated water passes through a crystallizer to form salt and then is recycled or landfilled. However, desulfurization wastewater contains a large amount of SO 4 2- , Ca 2+ 、Na + and Cl - wait. SO 4 2- and Ca 2+ , which is gypsum that has not been completely precipitated. If a large amount of reagents are used for precipitation, it will cause a waste of energy and the generation of a large amount of solid waste. If the flue gas evaporation technology is used, Na + and Cl - Spraying it into the ash residue may affect the quality of fly ash. If the salt obtained by concentrated crystallization contains some impurities, the purity is insufficient, which affects the sale of the salt. Therefore, the current treatment method of desulfurization wastewater causes SO 4 2- , Ca 2+ 、Na + and Cl - The waste of solid waste is large, resulting in a waste of energy. Therefore, developing a desulfurization wastewater zero-emission technology with low chemical consumption, low energy consumption, low investment and high resource utilization is an urgent problem to be solved in the field of environmental protection of thermal power plants. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the desulfurization wastewater treatment method in the prior art, such as SO 4 2- , Ca 2+ 、Na + and Cl - The waste of solid waste, large amount of solid waste, high energy consumption and other defects are eliminated, so as to provide a method that can fully utilize the SO in the desulfurization wastewater.4 2- , Ca 2+ 、Na + and Cl - , a desulfurization wastewater treatment system with small solid waste generation, low chemical consumption and low energy consumption.

[0005] In order to solve the above problems, the present invention provides a desulfurization wastewater treatment system, including a flow electrode electrosorption module, which includes a desulfurization wastewater inlet, a first brine outlet, a first flow electrode outlet and a first flow electrode inlet; a container, which includes a first container inlet, a second container inlet, a first container outlet and a second container outlet, the first container inlet is connected to the first flow electrode outlet, and the first container outlet is connected to the first flow electrode inlet; a flow electrode electrodialysis module, which includes a second flow electrode inlet, a second brine outlet and a second flow electrode outlet, the second flow electrode inlet is connected to the second container outlet, and the second flow electrode outlet is connected to the second container inlet; a bipolar membrane electrodialysis module, which includes a second brine inlet, a desalinated liquid outlet, an acid outlet and an alkali liquid outlet, and the second brine outlet is connected to the second brine inlet.

[0006] Further, the mobile electrode electrosorption module comprises:

[0007] shell;

[0008] a water distribution chamber formed at the bottom of the housing;

[0009] The anode electro-adsorption chamber and the cathode electro-adsorption chamber are arranged in the shell and laid on both sides of the shell respectively, the anode electro-adsorption chamber is connected to the positive electrode of the power supply, the cathode electro-adsorption chamber is connected to the negative electrode of the power supply, and the anode electro-adsorption chamber and the cathode electro-adsorption chamber are connected to the outlet of the first flow electrode;

[0010] A plurality of desalination units are arranged between the anode electrosorption chamber and the cathode electrosorption chamber and are spaced apart from each other, the bottom of the desalination unit is connected with the water distribution chamber, and the upper end of the desalination unit is connected with the first brine outlet.

[0011] Furthermore, the side wall of the desalination unit facing the anode electro-adsorption chamber includes at least two stacked first permeable partitions and a first monovalent selective anion exchange membrane sandwiched between the first permeable partitions, and the side of the desalination unit facing the cathode electro-adsorption chamber includes at least two first permeable partitions and a first monovalent selective cation exchange membrane sandwiched between the first permeable partitions. A water passage is formed between the side wall of the desalination unit facing the anode electro-adsorption chamber and the side wall facing the cathode electro-adsorption chamber, the bottom of the water passage is connected to the water distribution chamber, and the upper end of the water passage is connected to the first brine outlet.

[0012] Further, the anode electrosorption chamber comprises:

[0013] A second water-permeable separator, which is disposed in the housing and is suitable for separating the mobile electrode from the desulfurization wastewater;

[0014] A metal braided electrode, which is disposed between the second water-permeable baffle and the housing, and laid on the housing and / or the second water-permeable baffle, and is suitable for connecting to the positive electrode of the power supply;

[0015] a flow electrode formed within the metal braided electrode;

[0016] The cathode electrosorption chamber includes:

[0017] A second water-permeable separator, which is disposed in the housing and is suitable for separating the mobile electrode from the desulfurization wastewater;

[0018] A metal braided electrode, which is disposed between the second water-permeable separator and the housing, and laid on the housing and / or the second water-permeable separator, and is suitable for connecting to the negative electrode of the power supply;

[0019] A flow electrode formed within the metal braided electrode.

[0020] Furthermore, the mobile electrode electrosorption module further comprises:

[0021] A cleaning port, which passes through the water distribution chamber and communicates with the interior of the housing, and a side of the cleaning port away from the housing is suitable for connecting to a cleaning liquid;

[0022] A sewage outlet passes through the water distribution chamber and communicates with the interior of the shell.

[0023] Further, the mobile electrode electrodialysis module comprises:

[0024] A first anode plate and a first cathode plate, the first anode plate and the first cathode plate are arranged parallel to each other, the first anode plate is suitable for being connected to the positive electrode of the power supply, and the first cathode plate is suitable for being connected to the negative electrode of the power supply;

[0025] at least one second cation exchange membrane disposed between the first anode plate and the first cathode plate;

[0026] At least one second anion exchange membrane is arranged between the first anode plate and the first cathode plate and is staggered with the second cation exchange membrane. The second flow electrode inlet is formed at the liquid inlet end of the flow electrode electrodialysis module and is located between at least one group of second anion exchange membranes and second cation exchange membranes. The second flow electrode outlet is formed at the liquid outlet end of the flow electrode electrodialysis module and is located between at least one group of second anion exchange membranes and second cation exchange membranes. The second brine outlet is formed at the liquid outlet end of the flow electrode electrodialysis module and is staggered with the second flow electrode outlet.

[0027] Furthermore, the bipolar membrane electrodialysis module includes 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 arranged in sequence and spaced apart from each other. The second brine inlet is formed at the liquid inlet end of the bipolar membrane electrodialysis module and is located between the third anion exchange membrane and the third cation exchange membrane. The desalinated liquid outlet is formed at the liquid outlet end of the bipolar membrane electrodialysis module and is located between the third anion exchange membrane and the third cation exchange membrane. The acid liquid outlet is formed at the liquid outlet end of the bipolar membrane electrodialysis module and is located between the first bipolar membrane and the third anion exchange membrane. The alkali liquid outlet is formed at the liquid outlet end of the bipolar membrane electrodialysis module and is located between the third cation exchange membrane and the second bipolar membrane.

[0028] Furthermore, the desulfurization wastewater treatment system includes at least two bipolar membrane electrodialysis modules, and one group of bipolar membrane electrodialysis modules close to the flow electrode electrodialysis module in two adjacent groups of bipolar membrane electrodialysis modules is defined as a first bipolar membrane electrodialysis module, and the other group is a second bipolar membrane electrodialysis module, and the second brine inlet of the second bipolar membrane electrodialysis module is connected to the desalinated liquid outlet of the first bipolar membrane electrodialysis module.

[0029] Furthermore, the bipolar membrane electrodialysis module also includes:

[0030] an acid storage tank connected to the acid liquid outlet;

[0031] an alkali storage tank connected to an alkali solution outlet;

[0032] The desalinated water storage tank is connected to the desalinated liquid outlet.

[0033] Furthermore, the desulfurization wastewater treatment system also includes a sedimentation filtration module, which includes:

[0034] A reaction chamber, the reaction chamber is suitable for receiving desulfurization wastewater, a stirring device is arranged in the reaction chamber, and a guide tube with open ends is sleeved on the outer periphery of the stirring device;

[0035] A settling chamber connected to the reaction chamber, wherein the settling chamber is divided into at least two mutually connected settling partitions by at least one longitudinal partition;

[0036] The filter chamber is connected with the sedimentation chamber. A filter device is arranged in the filter chamber. The filter chamber is connected with the desulfurization wastewater inlet of the flow electrode electric adsorption module.

[0037] Further, the alkali solution outlet is connected to the reaction chamber of the sedimentation filtration module; and / or,

[0038] The filter chamber is connected to the desulfurization wastewater inlet of the flow electrode electric adsorption module through a first pipeline, and the acid liquid outlet is connected to the first pipeline.

[0039] Furthermore, the desulfurization wastewater treatment system also includes a ceramic microfiltration device connected between the outlet of the filter chamber and the desulfurization wastewater inlet of the flow electrode electrosorption module.

[0040] The present invention has the following advantages:

[0041] The desulfurized wastewater treatment system of the present invention comprises a flow electrode electrosorption module, a container, a flow electrode electrodialysis module and a bipolar membrane electrodialysis module. The flow electrode electrosorption module can receive desulfurized wastewater and selectively absorb Na in the desulfurized wastewater through its flow electrode and desalination membrane unit. + and Cl - , to generate a reserved SO 4 2- and Ca 2+ The first brine can be discharged through the first brine outlet to be reused in the desulfurization process, thereby avoiding SO 4 2- and Ca 2+ On the one hand, the device realizes the integration of salt separation and desalination by coupling the monovalent selective ion exchange membrane with the electric adsorption, which greatly improves the energy utilization rate and material utilization rate. On the other hand, since the desulfurization wastewater treatment system of the present invention does not need to treat Ca 2+ Precipitation can save a lot of reagents such as Ca(OH) 2 、CaCO 3 etc., and reduces the generation of solid waste, thereby saving the cost incurred by treating solid waste.

[0042] Carrying Na + and Cl - The flow electrode can enter the first container inlet of the container through the first flow electrode outlet, and then enter the second flow electrode inlet of the flow electrode electrodialysis module through the first container outlet. The flow electrode electrodialysis module can remove Na + and Cl - , to regenerate the mobile electrode and generate Na + and Cl - The regenerated flow electrode can be returned to the container through the second flow electrode outlet and the second container inlet in sequence, so as to be circulated and used by the flow electrode electrosorption module.

[0043] The mobile electrode electrosorption coupled with the mobile electrode electrodialysis system realizes the dynamic balance of the water-salt system under the industrial mode of desulfurization wastewater feeding and discharging. Therefore, the system has a strong ability to resist shock loads, and the inspection and replacement of the mobile electrosorption material can also be carried out in the container.

[0044] The second salt water can enter the bipolar membrane electrodialysis module through the second salt water outlet, and the bipolar membrane electrodialysis module can prepare the second salt water into light salt water, hydrochloric acid and sodium hydroxide solution. Among them, hydrochloric acid and sodium hydroxide solution can be reused to various acid and alkaline points in the thermal power plant, such as acid and alkali dosing, raw water pretreatment dosing, boiler feed water cleaning dosing, etc. in this system, and the light salt water can be reused in the boiler feed water reverse osmosis system or in the coal yard for spraying and dust suppression. In summary, the desulfurization wastewater treatment system of the present invention can convert SO in the desulfurization wastewater into 4 2- and Ca 2+ Reuse in the desulfurization system to form gypsum, Na + and Cl - It can be prepared into brine, hydrochloric acid and sodium hydroxide solution, thereby realizing the resource utilization of desulfurization wastewater without the need for additional softening agents, reducing the generation of solid waste and saving the cost of solid waste treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0046] Figure 1 A schematic diagram of a desulfurization wastewater treatment system according to an embodiment of the present invention is shown;

[0047] Figure 2 It is a mobile electrode electrosorption module of a desulfurization wastewater treatment system according to an embodiment of the present invention;

[0048] Figure 3 A top view of a flow electrode electrosorption module of a desulfurization wastewater treatment system according to an embodiment of the present invention;

[0049] Figure 4 It is a desalination module of a mobile electrode electric adsorption module of a desulfurization wastewater treatment system according to an embodiment of the present invention;

[0050] Figure 5 It is the anode electrosorption chamber of the desulfurization wastewater treatment system according to an embodiment of the present invention;

[0051] Figure 6 for Figure 5 A cross-sectional view of the anode electrosorption chamber shown in ;

[0052] Figure 7 A mobile electrode electrodialysis module of a desulfurization wastewater treatment system according to an embodiment of the present invention;

[0053] Figure 8 A bipolar membrane electrodialysis module of a desulfurization wastewater treatment system according to an embodiment of the present invention;

[0054] Fig. 9 It is a sedimentation filtration module of the desulfurization wastewater treatment system according to an embodiment of the present invention.

[0055] Description of reference numerals:

[0056] 1. Flow electrode electrosorption module; 11. Shell; 111. Cleaning port; 112. Drain port; 12. Water distribution chamber; 13. Anode electrosorption chamber; 131. Second permeable baffle; 132. Metal braided electrode; 14. Cathode electrosorption chamber; 15. Desalination unit; 152. First permeable baffle; 153. First monovalent selective anion exchange membrane; 154. First monovalent selective cation exchange membrane; 16. Desulfurization wastewater inlet; 17. First brine outlet; 18. First flow electrode inlet; 19. First flow electrode outlet; 2. Container; 21. First container inlet; 22. First container outlet; 23. Second container inlet; 24. Second container outlet; 3. Flow electrode electrodialysis module ; 31. first anode plate; 32. first cathode plate; 33. second anion exchange membrane; 34. second cation exchange membrane; 35. second flow electrode inlet; 36. second brine outlet; 37. second flow electrode outlet; 4. bipolar membrane electrodialysis module; 41. second anode plate; 42. first bipolar membrane; 43. third anion exchange membrane; 44. third cation exchange membrane; 45. second bipolar membrane; 46. second cathode plate; 47. second brine inlet; 48. desalinated liquid outlet; 49. acid outlet; 410. alkali outlet; 5. sedimentation and filtration module; 51. reaction chamber; 52. stirring device; 53. guide tube; 54. sedimentation chamber; 55. filtration chamber; 6. ceramic microfiltration device. DETAILED DESCRIPTION

[0057] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0058] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0059] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0060] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0061] Figure 1 FIG. 1 is a schematic diagram of a desulfurization wastewater treatment system according to an embodiment of the present invention. Figure 1 As shown, this embodiment relates to a desulfurization wastewater treatment system, including a flow electrode electrosorption module 1, a container 2, a flow electrode electrodialysis module 3 and a bipolar membrane electrodialysis module 4. Among them, the flow electrode electrosorption module 1 includes a desulfurization wastewater inlet 16, a first brine outlet 17, a first flow electrode outlet 19 and a first flow electrode inlet 18. The container 2 includes a first container inlet 21, a second container inlet 23, a first container outlet 22 and a second container outlet 24. The first container inlet 21 is connected to the first flow electrode outlet 19. The first container outlet 22 is connected to the first flow electrode inlet 18. The flow electrode electrodialysis module 3 includes 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 container inlet 23. The bipolar membrane electrodialysis module 4 includes a second brine inlet 47, a desalinated liquid outlet 48, an acid outlet 49 and an alkali outlet 410, and the second brine outlet 36 is connected to the second brine inlet 47.

[0062] The desulfurized wastewater treatment system of this embodiment includes a flow electrode electrosorption module 1, a container 2, a flow electrode electrodialysis module 3 and a bipolar membrane electrodialysis module 4. The flow electrode electrosorption module 1 can receive desulfurized wastewater and selectively adsorb Na in the desulfurized wastewater through its flow electrode and desalination membrane unit. + and Cl - , to generate a reserved SO 4 2- and Ca 2+ The first brine can be discharged through the first brine outlet 17 to be reused in the desulfurization process, thereby avoiding SO 4 2- and Ca 2+ On the one hand, the device realizes the integration of salt separation and desalination by coupling the monovalent selective ion exchange membrane with the electric adsorption, which greatly improves the energy utilization rate and material utilization rate. On the other hand, since the desulfurization wastewater treatment system of this embodiment does not need to treat Ca 2+ Precipitation can save a lot of reagents such as Ca(OH) 2 、CaCO 3 etc., and reduces the generation of solid waste, thereby saving the cost incurred by treating solid waste.

[0063] Carrying Na + and Cl - The mobile electrode can enter the first container inlet 21 of the container 2 through the first mobile electrode outlet 19, and then enter the second mobile electrode inlet 35 of the mobile electrode electrodialysis module 3 through the first container outlet 22. The mobile electrode electrodialysis module 3 can remove Na + and Cl - , to regenerate the mobile electrode and generate Na + and Cl - The regenerated flow electrode can be returned to the container 2 through the second flow electrode outlet 37 and the second container inlet 23 in sequence, so as to be circulated and used by the flow electrode electrosorption module 1.

[0064] The mobile electrode electrosorption coupled mobile electrode electrodialysis system realizes the dynamic balance of the water-salt system under the industrial mode of desulfurization wastewater feeding and discharging. Therefore, the system has a strong ability to resist shock loads. The inspection and replacement of the mobile electrosorption material can also be carried out in container 2.

[0065] The second salt water can enter the bipolar membrane electrodialysis module 4 through the second salt water outlet 36, and the bipolar membrane electrodialysis module 4 can prepare the second salt water into light salt water, hydrochloric acid and sodium hydroxide solution. Among them, hydrochloric acid and sodium hydroxide solution can be reused to various acid and alkaline points in the thermal power plant, such as acid and alkali dosing, raw water pretreatment dosing, boiler feed water cleaning dosing, etc. in this system, and the light salt water can be reused in the boiler feed water reverse osmosis system or in the coal yard for spraying and dust suppression. In summary, the desulfurization wastewater treatment system of this embodiment can convert SO in the desulfurization wastewater into 4 2- and Ca 2+ Reuse in the desulfurization system to form gypsum, Na + and Cl - It can be prepared into brine, hydrochloric acid and sodium hydroxide solution, thereby realizing the resource utilization of desulfurization wastewater without the need for additional softening agents, reducing the generation of solid waste and saving the cost of solid waste treatment.

[0066] The flow electrode electrosorption module 1 may optionally include an anode plate, an anion exchange membrane, a cation exchange membrane and a cathode plate arranged in parallel. The flow electrode is located between the anion exchange membrane and the cation exchange membrane, and the desulfurized wastewater is located between the anode plate and the anion exchange membrane, and between the cathode plate and the cation exchange membrane.

[0067] Preferably, if Figure 2 and Figure 3 As shown, in this embodiment, the flow electrode electrosorption module 1 includes a shell 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 shell 11. The anode electrosorption chamber 13 and the cathode electrosorption chamber 14 are arranged in the shell 11 and are respectively laid on both sides of the shell 11. The anode electrosorption chamber 13 is connected to the positive pole of the power supply. The cathode electrosorption chamber 14 is connected to the negative pole of the power supply. The anode electrosorption chamber 13 and the cathode electrosorption chamber 14 are connected to the first flow electrode outlet 19. A plurality of desalination units 15 are arranged between the anode electrosorption chamber 13 and the cathode electrosorption chamber 14 and are spaced apart from each other. The bottom of the desalination unit 15 is connected to the water distribution chamber 12, and the upper end of the desalination unit 15 is connected to the first brine outlet 17.

[0068] The flow electrode electrosorption module 1 of the present embodiment modularizes the desalination unit 15, and the various desalination units 15 are arranged in a staggered manner, thereby avoiding the problems of small ion exchange membrane area caused by conventional membrane arrangement, reduced desalination efficiency caused by insufficient ion transmission capacity, and severe membrane polarization. The flow electrode electrosorption module 1 of the present embodiment increases the ion exchange membrane area, and due to the modular arrangement of the desalination unit 15, the operator can open the shell and pull out the desalination unit 15 during maintenance and replacement. The flow electrode electrosorption module 1 of the present embodiment facilitates the replacement and maintenance of the electrosorption equipment.

[0069] Specifically, the water distribution chamber 12 may include a partition for separating the water distribution chamber 12 from the upper space of the housing 11. The partition is provided with a plurality of water outlets matching the cross-section of the desalination unit 15, and the bottoms of the plurality of desalination modules are sealed and connected to the plurality of water outlets one by one.

[0070] The size of the desalination unit 15 can be adaptively set according to factors such as the flow rate, salt content and size of the shell 11 of the desulfurized wastewater. Preferably, in this embodiment, the length of the desalination unit 15 is 10 cm, the width is 2.5 cm, and the height is 100 cm. The area of ​​the first monovalent selective anion exchange membrane 153 and the first monovalent selective cation exchange membrane 154 can be calculated based on the desalination amount. The current density of the first monovalent selective anion exchange membrane 153 and the first monovalent selective cation exchange membrane 154 can be selected to be between 280 and 360 A / m 2 between.

[0071] like Figure 4 As shown, in this embodiment, the side wall of the desalination unit 15 facing the anode electrosorption chamber 13 includes at least two first permeable baffles 152 stacked and a first monovalent selective anion exchange membrane 153 sandwiched between the first permeable baffles 152. The side of the desalination unit 15 facing the cathode electrosorption chamber 14 includes at least two first permeable baffles 152 and a first monovalent selective cation exchange membrane 154 sandwiched between the first permeable baffles 152. A water passage is formed between the side wall facing the anode electrosorption chamber 13 and the side wall facing the cathode electrosorption chamber 14. The bottom of the water passage is connected to the water distribution chamber 12, and the upper end of the water passage is connected to the first brine outlet 17. The other two side walls of the water passage can be optionally composed of impermeable baffles. In an embodiment not shown, the desalination unit 15 has a desalination unit shell, and the side wall of the desalination unit shell facing the anode electrosorption chamber 13 and the side wall facing the cathode electrosorption chamber 14 are made of permeable baffles sandwiching ion exchange membranes. The other two side walls of the desalination unit housing are composed of water-impermeable partitions, which are preferably made of insulating polypropylene.

[0072] The flow rate of the desulfurized wastewater in the desalination unit 15 is preferably in the range of 6-8 cm / s, which can prevent the formation of calcium sulfate. - and Na + Under the action of the electric field, SO 4 2- and Ca 2+ The water is blocked and flows out from the top of the desalination unit 15, and is recycled to the desulfurization process water tank and continues to be used for desulfurization to form gypsum. This process completes the salt separation and SO 4 2- and Ca 2+Since the sulfate and sodium chloride contents in desulfurization wastewater are similar, the osmotic pressure on both sides of the membrane is greatly reduced, which can extend the service life of the membrane.

[0073] like Figure 5 and Figure 6 As shown, in this embodiment, the anode electrosorption chamber 13 preferably includes a second permeable partition 131, a metal braided electrode 132 and a flow electrode. The second permeable partition 131 is arranged in the housing 11, suitable for separating the flow electrode from the desulfurization wastewater, so that most of the flow electrodes are confined in the anode electrosorption chamber 13. The metal braided electrode 132 is arranged between the second permeable partition 131 and the housing 11, and is laid on the housing 11 and / or the second permeable partition 131, and is suitable for connecting to the positive pole of the power supply. The flow electrode is formed in the metal braided electrode 132.

[0074] The cathode electrosorption chamber 14 includes a second permeable partition 131, a metal braided electrode 132 and a flow electrode. The second permeable partition 131 is arranged in the housing 11, and is suitable for separating the flow electrode from the desulfurization wastewater, so that most of the flow electrodes are confined in the cathode electrosorption chamber 14. The metal braided electrode 132 is arranged between the second permeable partition 131 and the housing 11, and is laid on the housing 11 and / or the second permeable partition 131, and is suitable for connecting to the negative pole of the power supply. The flow electrode is formed in the metal braided electrode 132.

[0075] The second permeable partition 131 can separate the electric adsorption chamber from the desalination unit 15. The pore size of the permeable partition is preferably 0.5 mm, which can confine most of the activated carbon in the cathode electric adsorption chamber 14 and the anode electric adsorption chamber 13 to prevent the high concentration of activated carbon from contaminating the ion exchange membrane, and will not affect the transmission of ions and water exchange. In addition, the permeable partition can facilitate the maintenance of the electric adsorption chamber. The operator only needs to open the shell 11 and pull out the electric adsorption chamber to complete the maintenance. The metal braided electrode 132 is preferably, but not limited to, a titanium-coated ruthenium electrode with strong corrosion resistance, which has a mesh structure, can increase the contact area with the flow electrode, and has a higher conductivity efficiency. The flow electrode is preferably, but not limited to, configured by granular activated carbon, acetylene black and additives in NaCl solution, and the activated carbon size is between 10 and 50 μm, with good adsorption performance and certain mechanical strength. The specific method of preparing the flow electrode is well known to those skilled in the art and will not be described in detail here. The voltage difference between the anode electrosorption chamber 13 and the cathode electrosorption chamber 14 is preferably maintained within the range of 1.0-1.5V.

[0076] After the mobile electrode is saturated with adsorption, it can enter the container 2 through the first mobile electrode outlet 19 and the first container inlet 21 in sequence, and the mobile electrodes flowing out of the cathode electrosorption chamber 14 and the anode electrosorption chamber 13 are mixed and enter the electrode electrodialysis unit. Preferably, a peristaltic pump is provided between the container 2 and the mobile electrode electrodialysis module 3. The peristaltic pump can drive the mobile electrode in the container 2 to flow into the mobile electrode electrodialysis module.

[0077] Preferably, in this embodiment, the flow electrode electrosorption module 1 further includes a cleaning port 111 and a sewage outlet 112. The cleaning port 111 passes through the water distribution chamber 12 and is connected to the interior of the shell 11, and the side of the cleaning port 111 away from the shell 11 is suitable for being connected to the cleaning liquid. The sewage outlet 112 passes through the water distribution chamber 12 and is connected to the interior of the shell 11. After the flow electrode electrosorption module 1 has been running for a period of time, the cleaning port 111 can spray cleaning liquid to clean the desalination unit 15 and the electrosorption chamber inside the shell 11, and the cleaning liquid can flow out through the sewage outlet 112. Preferably, the cleaning liquid uses the acid and alkali produced by bipolar membrane electrodialysis, and the acid and alkali solution with a reagent concentration of 3% and 1% are configured. The cleaning is carried out in the order of water washing-acid washing-water washing-alkali washing-water washing-acid washing-water washing. Acid washing can remove inorganic scale produced by high-price salt, and alkali washing can remove organic scale. The acid and alkali produced by the bipolar membrane electrodialysis module 4 are used to save the cost of cleaning.

[0078] In this embodiment, if Figure 7 As shown, 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 arranged in parallel with each other. The first anode plate 31 is suitable for being connected to the positive pole of the power supply, and the first cathode plate 32 is suitable for being connected to the negative pole of the power supply. At least one second anion exchange membrane 33 is arranged between the first anode plate 31 and the first cathode plate 32. At least one second cation exchange membrane 34 is arranged between the first anode plate 31 and the first cathode plate 32, and is staggered with the second cation exchange membrane 34. The second flow electrode inlet 35 is formed at the liquid inlet end of the flow electrode electrodialysis module 3 and is located between at least one group of the second anion exchange membrane 33 and the second cation exchange membrane 34. The second flow electrode outlet 37 is formed at the liquid outlet end of the flow electrode electrodialysis module 3 and is located between at least one group of the second anion exchange membrane 33 and the second cation exchange membrane 34. The second brine outlet 36 is formed at the liquid outlet end of the flow electrode electrodialysis module 3 and is arranged alternately with the second flow electrode outlet 37 .

[0079] The water inlet channel of the second anion exchange membrane 33 and the second cation exchange membrane 34 is preferably greater than 5mm to prevent the blockage of activated carbon. The ion exchange membrane of the mobile electrode electrodialysis module 3 has strong wear resistance and certain anti-pollution performance. The mobile electrode is quickly desalted in the mobile electrode electrodialysis module 3 to achieve the regeneration of the mobile electrode. The regenerated mobile electrode enters the container 2 and is sent to the mobile electrode electrodialysis module by a peristaltic pump to adsorb again so that the mobile electrode achieves a balance of adsorption and desorption in the system and realizes the recycling of the mobile electrode. The mobile electrode electrodialysis module can be optionally further provided with a concentrated water tank, a pole water tank, and a control box. Among them, the concentrated water tank is used to accommodate the liquid discharged from the second brine outlet 36. The pole water tank includes an anode water tank and a cathode water tank, the anode water tank is used to accommodate the anode liquid and the anode liquid is circulated therein, and the cathode water tank is used to accommodate the cathode liquid and the cathode liquid is circulated therein.

[0080] In this embodiment, if Figure 8 As shown, 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 arranged in sequence and spaced apart from each other. A second salt water inlet 47 is formed at the liquid inlet 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. A desalinated 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 solution 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. An alkali solution 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.

[0081] The desulfurization wastewater treatment system of this embodiment may optionally include a group of bipolar membrane electrodialysis modules 4. Preferably, in this embodiment, the desulfurization wastewater treatment system includes at least two bipolar membrane electrodialysis modules 4, and one group of bipolar membrane electrodialysis modules 4 close to the flow electrode electrodialysis module in two adjacent groups of bipolar membrane electrodialysis modules 4 is defined as the first bipolar membrane electrodialysis module 4, and the other group is the second bipolar membrane electrodialysis module 4. The second brine inlet 47 of the second bipolar membrane electrodialysis module 4 is connected to the desalinated liquid outlet 48 of the first bipolar membrane electrodialysis module 4. It can enhance the resource utilization effect of desulfurization wastewater. For example, in this embodiment, the desulfurization wastewater treatment system includes three bipolar membrane electrodialysis modules 4 connected in series.

[0082] The first group of bipolar membrane electrodialysis modules 4 can achieve the utilization of 70% of the salt, the second group of bipolar membrane electrodialysis modules 4 can achieve the utilization of 65% of the salt, and the third group of bipolar membrane electrodialysis modules can achieve the utilization of 60% of the salt, and finally more than 95% of the salt is prepared into acid and alkali, and 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 reused to various acid and alkali points in thermal power plants, such as acid and alkali dosing, raw water pretreatment dosing, boiler feed water cleaning dosing, etc. in this system, which greatly reduces the pretreatment cost of water replenishment in thermal power plants. The light salt water can be reused in the boiler feed water reverse osmosis system or in the coal yard for spraying and dust suppression. In addition, the use of bipolar membrane electrodialysis modules 4 to separate the salt in the desulfurization wastewater has the advantages of a short process chain and less impurities in the produced salt compared to the methods such as concentration and crystallization in the prior art.

[0083] In this embodiment, the bipolar membrane electrodialysis module 4 further includes an acid storage tank, an alkali storage tank and a salt water storage tank. The acid storage tank is connected to the acid outlet 49. The alkali storage tank is connected to the alkali outlet 410. The salt water storage tank is connected to the desalinated liquid outlet 48.

[0084] In this embodiment, if Fig. 9 As shown, the desulfurization wastewater treatment system preferably also includes a sedimentation and filtration module 5. The sedimentation and filtration module 5 includes a reaction chamber 51, a sedimentation chamber 54 and a filter chamber 55. The reaction chamber 51 is suitable for receiving desulfurization wastewater. A stirring device 52 is arranged in the reaction chamber 51. A guide tube 53 with open ends is sleeved on the outer periphery of the stirring device 52. The sedimentation chamber 54 is connected to the reaction chamber 51. The sedimentation chamber 54 is divided into at least two mutually connected sedimentation partitions by at least one longitudinal partition. The filter chamber 55 is connected to the sedimentation chamber 54, and a filtration device is arranged in the filter chamber 55. The filter chamber 55 is connected to the desulfurization wastewater inlet 16 of the flow electrode electrosorption module 1.

[0085] The sedimentation filtration module 5 of this embodiment is targeted at the characteristics of desulfurization wastewater. By arranging a guide tube 53 on the periphery of the stirring device 52, a vortex is formed in the guide tube 53 as the stirring proceeds, thereby enhancing the mixing degree of the desulfurization wastewater and the absorbent; the multiple sedimentation partitions formed by the longitudinal partitions realize the multi-stage sedimentation of the desulfurization wastewater. Compared with the traditional triple box, it has the advantages of simple structure, strong mixing ability and good separation effect. Preferably, a high-efficiency composite desulfurization wastewater treatment agent and NaOH are added to the sedimentation filtration module 5 of this embodiment to replace traditional flocculants, coagulants, organic sulfur, lime or sodium carbonate and other agents.

[0086] The reagent includes inorganic materials such as diatomite, zeolite molecular sieve, activated carbon, bentonite, etc. Compared with traditional reagents, it has the advantages of lower operating costs, simple operation, high effluent stability, and halved sludge volume. It can be perfectly docked with the subsequent mobile electrode electrosorption module 1, mobile electrode electrodialysis module 3 and bipolar membrane electrodialysis module 4, and will not affect the membrane. In particular, it can solve the problems of COD, heavy metals, fluorides and membrane blockage. It can also shorten the flocculation time, so that the flocculation time is reduced from the traditional greater than or equal to 30 minutes to 5-10 minutes, and the sedimentation time is reduced from the traditional greater than or equal to 6 hours to 1-2 hours. Therefore, the equipment volume and floor space can be greatly reduced. And because there is no need to add lime, the amount of mud produced is reduced by about half, saving the cost of sludge treatment. The desulfurization wastewater after separation and clarification is simply filtered through the filter chamber 55 to remove suspended matter, etc. HCl is added to the outlet to adjust the pH to 7.

[0087] The F ion concentration in the treated wastewater is below 5 mg / L. NaOH is added to adjust the pH to 11, remove a large amount of magnesium ions, and control the concentration of magnesium ions below 200 mg / L. The formed Mg(OH) 2 It is then adsorbed and co-precipitated by a high-efficiency composite agent, which can achieve a better removal effect.

[0088] Preferably, in this embodiment, the alkali solution outlet 410 is connected to the reaction chamber 51 of the sedimentation filtration module 5. The filter chamber 55 is connected to the desulfurization wastewater inlet 16 of the mobile electrode electrosorption module 1 through the first pipeline, and the acid solution outlet 49 is connected to the first pipeline. This allows the alkali solution produced by the bipolar membrane electrodialysis module 4 to be introduced 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 solution produced by the bipolar membrane electrodialysis module 4 can be introduced into the first pipeline to adjust the pH of the desulfurization wastewater, thereby making full use of the product of the bipolar membrane electrodialysis module 4 and greatly reducing the cost of adding drugs.

[0089] In this embodiment, the desulfurization wastewater treatment system also includes a ceramic microfiltration device 6 connected between the outlet of the filter chamber 55 and the desulfurization wastewater inlet 16 of the mobile electrode electrosorption module 1. The wastewater after sedimentation filtration still contains a large amount of inorganic salts and suspended matter, and has a high hardness. The chemical properties, mechanical strength and service life of conventional organic microfiltration equipment are difficult to meet the microfiltration requirements of desulfurization wastewater. The desulfurization wastewater treatment system of this embodiment uses a ceramic microfiltration device 6 to filter the desulfurization wastewater. It has high mechanical strength, high flux, is not easy to clog, has a long service life, and is easy to maintain. It can meet the filtration requirements of desulfurization wastewater, and domestic products can meet the operating requirements and reduce equipment costs.

[0090] Preferably, in this embodiment, the ceramic microfiltration device 6 includes a feed pump, a ceramic microfiltration membrane device and a cleaning system. The ceramic microfiltration membrane is preferably a large-pore microfiltration membrane, the pore size can be selected to be in the range of 0.1 to 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 The cleaning system is preferably connected to the acid storage tank and the alkali storage tank of the bipolar membrane electrodialysis module 4, and can use the product of the bipolar membrane electrodialysis module 4 to perform acid and alkali washing on the desulfurization wastewater after microfiltration. After microfiltration, the suspended solids in the wastewater are less than 1NTU, meeting the water inlet requirements of the ion exchange membrane.

[0091] Next, an embodiment of treating desulfurization wastewater using the desulfurization wastewater treatment system of the present invention is introduced:

[0092] A 2×350,000 kW coal-fired power plant adopts limestone-gypsum wet desulfurization process, one furnace and one tower arrangement, and the desulfurization wastewater volume is about 10t / h. 3 The desulfurization wastewater treatment system of the present invention is used to treat desulfurization wastewater, and the water quality and water volume at each stage are as follows:

[0093] Stages Raw water After preprocessing First salt water Second salt water Salt water <![CDATA[Water volume / m 3 > 15 15 13.5 1.35 0.55 TDS 35000 35000 18900 200000 8400 SS 25100 5 6 0 0 <![CDATA[Ca 2 + ]]> 1900 1900 2110 0 0 <![CDATA[Mg 2 + ]]> 3614 200 230 0 0 <![CDATA[Na + ]]> 7524 7524 500 78630 1817 <![CDATA[Cl - ]]> 12500 12500 1760 121300 5097 <![CDATA[F - ]]> 80 0 0 0 0 <![CDATA[SO 4 2- ]]> 8300 8300 9200 200 0

[0094] Note: Ion units are all mg / L

[0095] As can be seen from the table, using the desulfurization wastewater treatment system of the embodiment of the present invention, the direct reuse rate of desulfurization wastewater is as high as 90%, Ca 2 + , Na + , SO 4 2- and Cl - The recycling rate of major ion salts is as high as 95%, and the resource utilization level is extremely high. In terms of investment and operating costs, compared with the currently commonly used zero-emission technology, although the ceramic microfiltration device 6 and the bipolar membrane electrodialysis module 4 are more expensive, they can save more than 50% of the system's floor space and civil engineering costs, so the total investment is still slightly lower than the existing technology.

[0096] In terms of operating costs, the cost of chemicals is about 9 yuan / m 3 (including special defluorination agent), the system power consumption is about 46.3kW·h / m 3 Most of the power consumption is for the bipolar membrane electrodialysis module 4, and the power plant price is 0.4 yuan kW·h / m 3 Calculation, the operating cost is 27.5 yuan / m 3 , and generated 3m 3About 1.4 mol / L of acid and alkali are directly reused in the dosing of the high-density clarification tank for pretreatment of reclaimed water in the power plant. After conversion, the cost of adding alkali is directly saved by 336 yuan / h (2,000 yuan / ton for finished alkali) and 148 yuan / h for acid (31% industrial hydrochloric acid is 300 yuan / ton), making the power plant obtain a net profit of 456.5 yuan / h, achieving good economic benefits. In addition, no waste salt is generated, achieving zero discharge of desulfurization wastewater from coal-fired power plants and reuse of waste salt resources, and achieving good environmental protection and ecological benefits.

[0097] In summary, the desulfurization wastewater treatment system of the present invention has the following advantages:

[0098] 1. The desulfurization wastewater treatment system of the present invention can realize the reuse of 90% of the desulfurization wastewater on the basis of achieving zero discharge of desulfurization wastewater, and prepare the salt wastewater into acid and alkali, NaCl-CaSO 4 The material utilization rate is as high as over 95%.

[0099] 2. The desulfurization wastewater treatment system of the present invention uses the desulfurization wastewater integrated reaction and ceramic microfiltration device 6, and can complete the pretreatment of the desulfurization wastewater without adding a large amount of reagents for softening, thereby saving investment and operating costs.

[0100] 3. The desulfurization wastewater treatment system of the present invention can realize the salt separation and concentration of desulfurization wastewater with low energy consumption, and use mobile electrode electrodialysis to quickly regenerate mobile activated carbon. The use of this system has small footprint, continuous operation, high energy utilization, convenient maintenance, and high intelligence, which can meet the current needs of smart power plants.

[0101] 4. The present invention connects the multi-stage bipolar membrane electrodialysis modules 4 in series, which greatly improves the utilization rate of salt. The generated acid and alkali are directly reused in the power plant, and the remaining trace amount of light salt water is used for reverse osmosis or spraying in the coal yard, which produces considerable economic benefits.

[0102] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A desulfurization wastewater treatment system, characterized in that: include: A flow electrode electrosorption 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 container (2), comprising a first container inlet (21), a second container inlet (23), a first container outlet (22) and a second container outlet (24), wherein the first container inlet (21) is connected to the first flow electrode outlet (19), and the first container outlet (22) is connected to the 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), wherein the second flow electrode inlet (35) is connected to the second container outlet (24), and the second flow electrode outlet (37) is connected to the second container inlet (23); A bipolar membrane electrodialysis module (4) comprises a second salt water inlet (47), a desalinated liquid outlet (48), an acid liquid outlet (49) and an alkaline liquid outlet (410), wherein the second salt water outlet (36) is connected to the second salt water inlet (47).

2. The desulfurization wastewater treatment system according to claim 1, characterized in that: The mobile electrode electrosorption module (1) comprises: Housing (11); a water distribution chamber (12) formed at the bottom of the housing (11); an anode electrosorption chamber (13) and a cathode electrosorption chamber (14), which are arranged in the housing (11) and laid on both sides of the housing (11), respectively; the anode electrosorption chamber (13) is connected to the positive electrode of the power supply, the cathode electrosorption chamber (14) is connected to the negative electrode of the power supply, and the anode electrosorption chamber (13) and the cathode electrosorption chamber (14) are connected to the first flow electrode outlet (19); A plurality of desalination units (15), wherein the plurality of desalination units (15) are arranged between the anode electrosorption chamber (13) and the cathode electrosorption chamber (14) and are spaced apart from each other, the bottom of the desalination unit (15) is connected to the water distribution chamber (12), and the upper end of the desalination unit (15) is connected to the first brine outlet (17).

3. The desulfurization wastewater treatment system according to claim 2, characterized in that: The side wall of the desalination unit (15) facing the anode electrosorption chamber (13) comprises at least two first water-permeable baffles (152) stacked together and a first monovalent selective anion exchange membrane (153) sandwiched between the first water-permeable baffles (152); the side of the desalination unit (15) facing the cathode electrosorption chamber (14) comprises at least two first water-permeable baffles (152) and a first monovalent selective cation exchange membrane (154) sandwiched between the first water-permeable baffles (152); a water passage is formed between the side wall of the desalination unit (15) facing the anode electrosorption chamber (13) and the side wall of the desalination unit (15) facing the cathode electrosorption chamber (14); the bottom of the water passage is connected to the water distribution chamber (12), and the upper end of the water passage is connected to the first brine outlet (17).

4. The desulfurization wastewater treatment system according to claim 2, characterized in that: The anode electrosorption chamber (13) comprises: A second water-permeable partition (131), which is arranged in the housing (11) and is suitable for separating the flow electrode from the desulfurization wastewater; a metal braided electrode (132), which is arranged between the second water-permeable baffle (131) and the housing (11), and is laid on the housing (11) and / or the second water-permeable baffle (131), and is suitable for being connected to the positive electrode of the power source; a flow electrode formed within the metal braided electrode (132); The cathode electrosorption chamber (14) comprises: A second water-permeable partition (131), which is arranged in the housing (11) and is suitable for separating the flow electrode from the desulfurization wastewater; a metal braided electrode (132), which is arranged between the second water-permeable baffle (131) and the housing (11), and is laid on the housing (11) and / or the second water-permeable baffle (131), and is suitable for being connected to the negative electrode of the power source; A flow electrode is formed within the metal braided electrode (132).

5. The desulfurization wastewater treatment system according to claim 2, characterized in that: The mobile electrode electrosorption module (1) further comprises: a cleaning port (111) passing through the water distribution chamber (12) and communicating with the interior of the housing (11); a side of the cleaning port (111) away from the housing (11) being suitable for being connected to a cleaning liquid; A sewage outlet (112) passes through the water distribution chamber (12) and communicates with the interior of the housing (11).

6. The desulfurization wastewater treatment system according to any one of claims 1 to 5, characterized in that: The mobile electrode electrodialysis module (3) comprises: A first anode plate (31) and a first cathode plate (32), wherein the first anode plate (31) and the first cathode plate (32) are arranged parallel to each other, the first anode plate (31) is suitable for being connected to a positive electrode of a power source, and the first cathode plate (32) is suitable for being connected to a negative electrode of the power source; at least one second anion exchange membrane (33) disposed between the first anode plate (31) and the first cathode plate (32); At least one second cation exchange membrane (34) is arranged between the first anode plate (31) and the first cathode plate (32), and is arranged alternately with the second cation exchange membrane (34); the second flow electrode inlet (35) is formed at the liquid inlet end of the flow electrode electrodialysis module (3), and is located between at least one group of the second anion exchange membrane (33) and the second cation exchange membrane (34); the second flow electrode outlet (37) is formed at the liquid outlet end of the flow electrode electrodialysis module (3), and is located between at least one group of the second anion exchange membrane (33) and the second cation exchange membrane (34); the second brine outlet (36) is formed at the liquid outlet end of the flow electrode electrodialysis module (3), and is arranged alternately with the second flow electrode outlet (37).

7. The desulfurization wastewater treatment system according to any one of claims 1 to 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) which are arranged in sequence and spaced apart from each other; the second salt water inlet (47) is formed at the liquid inlet 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); the desalinated liquid outlet (48) is formed at the liquid inlet end of the bipolar membrane electrodialysis module (4). The liquid outlet of the bipolar membrane electrodialysis module (4) is located between the third anion exchange membrane (43) and the third cation exchange membrane (44); the acid solution outlet (49) is formed at the liquid outlet of the bipolar membrane electrodialysis module (4) and is located between the first bipolar membrane (42) and the third anion exchange membrane (43); and the alkali solution outlet (410) is formed at the liquid outlet of the bipolar membrane electrodialysis module (4) and is located between the third cation exchange membrane (44) and the second bipolar membrane (45).

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), wherein one group of bipolar membrane electrodialysis modules (4) close to the flow electrode electrodialysis module in two adjacent groups of bipolar membrane electrodialysis modules (4) is defined as a first bipolar membrane electrodialysis module (4), and the other group is defined as a second bipolar membrane electrodialysis module (4), wherein a second brine inlet (47) of the second bipolar membrane electrodialysis module (4) is 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 storage tank connected to the acid liquid outlet (49); an alkali storage tank connected to the alkali solution outlet (410); A salt water storage tank is connected to the desalinated liquid outlet (48).

10. The desulfurization wastewater treatment system according to any one of claims 1 to 5, characterized in that: It also includes a sedimentation filtration module (5), wherein the sedimentation filtration module (5) includes: A reaction chamber (51), wherein the reaction chamber (51) is suitable for receiving desulfurized wastewater, wherein a stirring device (52) is arranged in the reaction chamber (51), and a guide tube (53) with two open ends is sleeved on the outer periphery of the stirring device (52); A sedimentation chamber (54) is connected to the reaction chamber (51), wherein the sedimentation chamber (54) is divided into at least two mutually connected sedimentation partitions by at least one longitudinal partition; A filter chamber (55) is connected to the sedimentation chamber (54), a filter device is arranged in the filter chamber (55), and the filter chamber (55) is connected to the desulfurization wastewater inlet (16) of the flow electrode electric adsorption module (1).

11. The desulfurization wastewater treatment system according to claim 10, characterized in that: The alkali solution outlet (410) is connected to the reaction chamber (51) of the sedimentation filtration module (5); and / or, The filter chamber (55) is connected to the desulfurization wastewater inlet (16) of the flow electrode electrosorption module (1) via a first pipeline, and the acid solution outlet (49) is connected to the first pipeline.

12. The desulfurization wastewater treatment system according to claim 10, characterized in that: It also includes a ceramic microfiltration device (6) connected between the outlet of the filter chamber (55) and the desulfurization wastewater inlet (16) of the flow electrode electrosorption module (1).

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