A system for bromine extraction from concentrated seawater and acid-base production

Abstract

The utility model discloses a kind of from production acid-base's concentrated seawater bromine extraction resource system, it is related to seawater resource technology field, including parallel coupling configuration's air blow method seawater bromine extraction system and bipolar membrane acid-base system;On the basis of seawater bromine extraction system using air blow method, introduce bipolar membrane electrodialysis as bypass system, handle part seawater, obtain the acid-base of satisfying production requirement concentration, use acid for subsequent seawater acidification process, alkali is used to neutralize the acidic bromine extraction mother liquor generated.The method does not affect the original seawater bromine extraction process under the premise, by adjusting the acid-base concentration and feed liquid treatment capacity of bipolar membrane acid-base system, both can satisfy seawater bromine extraction process system's acid-base use demand, also can produce economic value's acid-base product outside sale according to actual operation situation.In the realization of waste liquid standard discharge, reduce the demand of enterprise acid-base acquisition, can provide feasibility strategy for enterprise cost reduction and efficiency improvement.

Description

Technical Field

[0001] This utility model relates to the field of seawater resource utilization technology, and more specifically to the field of a method for extracting bromine from concentrated seawater that produces its own acids and alkalis. Background Technology

[0002] Bromine is an important chemical raw material with significant applications in flame retardants, pharmaceuticals, pesticides, fine chemicals, and oilfield extraction. In nature, bromine is mainly found in seawater, mineral brine, concentrated underground brine, and salt lakes. While seawater has a relatively low bromine concentration, only around 60 mg / L, its vast ocean area means it contains approximately 99% of the Earth's total bromine reserves. Currently, bromine resources in underground brine are becoming increasingly scarce due to frequent extraction. Extracting bromine from seawater will become the mainstream development trend for elemental bromine production in the future, possessing broad market prospects and research value.

[0003] Currently, over 90% of seawater bromine extraction technologies in my country utilize the air blowing method. The basic principle involves oxidizing bromide ions in seawater into free bromine under acidic conditions using chlorine gas. Then, utilizing gas-liquid equilibrium, air is used to blow the free bromine out of the seawater, which is then absorbed by acid or alkali, forming a high-concentration bromine-containing mother liquor. Finally, the bromine in the mother liquor is oxidized to elemental bromine, which is then distilled and condensed to obtain the elemental bromine product. This process, including seawater acidification, wastewater treatment, and alkali absorption, consumes large amounts of acid and alkali, increasing production costs for enterprises. However, because the feed liquid (seawater) used for bromine extraction has a high salinity, it can be pretreated and then processed using bipolar membrane electrodialysis technology to prepare acids and alkalis of the required concentrations for production. Therefore, coupling bipolar membrane acid and alkali production technology with the seawater bromine extraction process, converting seawater salt ions into acids and alkalis for reuse in multiple production steps of seawater bromine extraction, can effectively reduce reagent purchase costs, lower operating costs, and improve economic efficiency for enterprises. Currently, there are reports on the application of bipolar membrane electrodialysis technology to seawater bromine extraction processes.

[0004] Patent CN102311097A proposes using bipolar membrane electrodialysis technology in the seawater bromine extraction process via ion exchange resin adsorption. The bipolar membrane's cells are used to oxidize bromine, replacing the oxidation process in the original process. However, due to the low bromide ion content in seawater and the large volume of feed liquid to be treated, directly replacing the oxidation process with bipolar membrane technology would significantly increase the footprint and investment / operating costs, making industrial application difficult.

[0005] Patent CN117303630A proposes treating the mother liquor from air-blowing distillation using an electrodialysis system and a bipolar membrane system to prepare a feed solution enriched with acid or alkali, which can then be reused in the acidification or alkaline absorption steps of the bromine extraction process. However, the distillation mother liquor processed by this method typically contains some unreacted free chlorine, which can damage the membrane elements in the bipolar membrane electrodialysis equipment, thereby reducing the lifespan of the bipolar membrane electrodialysis device.

[0006] In summary, developing a safe and reliable integrated process system for bipolar membrane electrodialysis and seawater bromine extraction, enabling the self-production of acids and alkalis required for the bromine extraction process, is of great significance for improving the correlation of process operation, reducing operating costs, and enhancing the economic efficiency of the process. Utility Model Content

[0007] The purpose of this invention is to address the aforementioned technical problems by providing a method for the resource utilization of concentrated seawater for bromine extraction by self-producing acids and alkalis. Based on a seawater bromine extraction system using air blowing, a bipolar membrane electrodialysis system is introduced as a bypass system to treat a portion of the seawater, preparing acids and alkalis at concentrations meeting production requirements. The acid is used in subsequent seawater acidification processes, and the alkali is used to neutralize the resulting acidic bromine extraction mother liquor. This method, without affecting the original seawater bromine extraction process, adjusts the concentration of produced acids and alkalis and the feed liquid treatment rate of the bipolar membrane acid and alkali production system. This allows for both meeting the acid and alkali requirements of the seawater bromine extraction process and producing economically valuable acid and alkali products for external sale, depending on actual operating conditions. By achieving compliant wastewater discharge, this method reduces the enterprise's need to purchase acids and alkalis, providing a feasible strategy for cost reduction and efficiency improvement.

[0008] To achieve the above objectives, this utility model specifically adopts the following technical solution:

[0009] The first aspect of this utility model provides a concentrated seawater bromine extraction resource utilization system for producing acids and alkalis, including an air-blowing seawater bromine extraction system and a bipolar membrane acid and alkali production system configured in parallel and coupled.

[0010] The air-blowing seawater bromine extraction system includes an acidification oxidation unit, a blowing unit, an absorption unit, a secondary oxidation unit, and a distillation unit connected in sequence. The air-blowing seawater bromine extraction system also includes a neutralization treatment unit. The neutralization treatment unit is connected upstream to the absorption unit, and a discharge port is provided downstream of the neutralization treatment unit. The discharge port of the distillation unit is connected to a single-element bromine collection unit, and the distillation port of the distillation unit is connected to the acidification oxidation unit through a pipeline.

[0011] The bipolar membrane acid and alkali production system includes a pretreatment unit, a concentration unit, a bipolar membrane electrodialysis unit, an evaporation unit, and a sodium hydroxide collection unit connected in sequence. The reflux port of the bipolar membrane electrodialysis unit is connected to the concentration unit through a pipeline. The acid outlet of the bipolar membrane electrodialysis unit is connected to the acidification and oxidation unit. The alkali outlet of the bipolar membrane electrodialysis unit is divided into two pipelines, one of which is connected to the evaporation unit and the other of which is connected to the neutralization treatment unit through a pipeline.

[0012] The concentrated seawater pool is connected to the inlet of the acidification and oxidation unit and the inlet of the pretreatment unit via pipelines.

[0013] Specifically, by configuring a bipolar membrane acid and alkali production system and an air-blowing seawater bromine extraction process system in parallel and coupled, while ensuring the relative independence of the two process systems, a portion of the concentrated seawater that has not been acidified and oxidized is used as the feed water for the bipolar membrane system. The acid and alkali produced by the bipolar membrane system are recycled to the acidification, oxidation, and neutralization of the bromine extraction mother liquor in the bromine extraction process system. This achieves the self-production and use of acid and alkali for the seawater bromine extraction process, while also producing sodium hydroxide, a product with high economic value, as a byproduct.

[0014] The acid and alkali products produced by the bipolar membrane electrodialysis acid and alkali production system meet the acid and alkali requirements of the bromine extraction process in terms of both quantity and quality. Depending on the specific circumstances, surplus acid and alkali products can also be upgraded and sold externally, resulting in good economic benefits.

[0015] In one embodiment, the acidification oxidation unit includes an oxidation tower and a desorption tower, and the secondary oxidation unit is a packed tower.

[0016] In one embodiment, the concentration unit is a concentration electrodialysis device or a reverse osmosis device.

[0017] The second aspect of this invention provides a method for bromine extraction from concentrated seawater using a self-generated acid-base system, employing the aforementioned self-generated acid-base system. This system includes a parallel-coupled air-blowing seawater bromine extraction process and a bipolar membrane acid-base production process.

[0018] The process of bromine extraction from seawater using the air blowing method is as follows:

[0019] A1. In the acidification and oxidation unit, the concentrated bromine-containing seawater is first acidified with acid to adjust its pH value to acidic.

[0020] A2. Next, chlorine gas is introduced into the oxidation tower of the acidification oxidation unit to oxidize the bromide ions in the concentrated seawater into elemental bromine.

[0021] A3. Then, elemental bromine is blown out of the desorption tower of the acidification oxidation unit with air. After being absorbed by the acid absorbent in the absorption tower of the absorption unit, the elemental bromine is reduced to bromide ions and enriched in the absorption liquid. The absorption liquid enriched with bromide ions is then subjected to secondary oxidation by chlorine gas introduced in the middle of the secondary oxidation unit to generate free bromine. Finally, the free bromine is condensed in the distillation unit to obtain elemental bromine, and the mother liquor of the distillation is returned to the acidification oxidation unit for reuse.

[0022] The bipolar membrane acid and alkali production process is as follows:

[0023] B1. Take a portion of the untreated concentrated seawater and pre-treat it in a pretreatment unit for hardening removal and desalination to reduce the salt concentration and Ca content in the concentrated seawater. 2+ Mg 2+ Once the impurity content reaches the requirements for bipolar membrane feed water, the concentrated seawater is further concentrated using the concentration unit.

[0024] B2. Then, the required acid and base are prepared by a bipolar membrane electrodialysis unit.

[0025] B3. The brine produced by the bipolar membrane electrodialysis unit is returned to the concentration unit for recycling to reduce wastewater discharge; the acid produced by the bipolar membrane electrodialysis unit is recycled to the acidification and oxidation unit of the air-blowing seawater bromine extraction system to adjust the pH of the seawater.

[0026] B4. A portion of the alkali produced by the bipolar membrane electrodialysis unit is returned to the neutralization treatment unit of the air-blowing bromine extraction system to neutralize the acidic bromine extraction mother liquor, ensuring it meets discharge standards. Any remaining alkali produced by the bipolar membrane electrodialysis unit can be concentrated in the evaporation unit to prepare sodium hydroxide, which can then be collected and reused in other process sections of the plant.

[0027] Specifically, this scheme designs a bipolar membrane acid-base generation system and an air-blowing seawater bromine extraction system in parallel. Without affecting the air-blowing method for seawater bromine extraction, the parallel bipolar membrane acid-base generation system can produce acid and alkali products that meet the requirements of the bromine extraction process, achieving resource recycling of seawater from multiple perspectives. Simultaneously, the parallel design between the bipolar membrane acid-base generation system and the seawater bromine extraction system effectively avoids the impact of oxidizing substances generated during bromine extraction on the bipolar membrane system, playing a positive role in extending the service life of the bipolar membrane system.

[0028] In one embodiment, in step B1, in the pretreatment section of the bipolar membrane acid and alkali production process, chemical precipitation, nanofiltration, and ion exchange can be used for hardening removal.

[0029] In one embodiment, when using chemical precipitation to remove hardness, the acid prepared is a mixture of sulfuric acid and hydrochloric acid;

[0030] When using NF for hardening treatment, chloride ions and sulfate ions can be separated simultaneously, and the acid prepared is mainly hydrochloric acid.

[0031] The beneficial effects of this utility model are as follows:

[0032] 1. This scheme uses a parallel configuration to couple a bipolar membrane acid and alkali production system and an air-blowing seawater bromine extraction process system. While ensuring the relative independence of the two process systems, a portion of the concentrated seawater that has not been acidified or oxidized is used as the feed water for the bipolar membrane system. The acid and alkali produced by the bipolar membrane system are recycled to the acidification, oxidation, and neutralization of the bromine extraction mother liquor processes in the bromine extraction process. This achieves the self-production and use of acid and alkali for the seawater bromine extraction process, while also producing sodium hydroxide, a product with high economic value, as a byproduct.

[0033] 2. This utility model fully considers the characteristic that the chlorine oxidant introduced in the seawater bromine extraction process cannot react completely. It uses un-acidified and unoxidized seawater as the feed water of the bipolar membrane acid-alkali system, thus avoiding the problem of free chlorine in the bromine extraction mother liquor or distillation mother liquor damaging the membrane material in the bipolar membrane system.

[0034] 3. This utility model combines a bipolar membrane acid / alkali production system and an air-blowing seawater bromine extraction system in parallel. Without affecting the air-blowing method for seawater bromine extraction, the parallel bipolar membrane acid / alkali production system generates acid and alkali products that meet the requirements of the bromine extraction process, achieving resource recycling of seawater from multiple perspectives. Furthermore, the parallel design between the bipolar membrane acid / alkali production system and the seawater bromine extraction system effectively avoids the impact of oxidizing substances generated during bromine extraction on the bipolar membrane system, thus playing a positive role in extending the service life of the bipolar membrane system.

[0035] 4. In air-blowing seawater bromine extraction projects using concentrated seawater from desalination as bromine feedstock, when the bromine extraction scale is 1500 tons / year, a parallel-coupled concentrated seawater bipolar membrane acid-alkali system with a capacity of 8-10 m³ / h can reduce the external demand for concentrated sulfuric acid by 2200-2500 tons / year and the external demand for 32% liquid alkali by 1800-2100 tons / year. The overall system's investment payback period is approximately 2-3 years. Furthermore, using un-acidified and unoxidized concentrated seawater as the feedwater for the bipolar membrane acid-alkali system effectively avoids the impact of incompletely reacted free chlorine in the bromine extraction mother liquor or distillation mother liquor on the bipolar membrane system, and the stable operation time of the bipolar membrane system is expected to increase by 1-2 times. Attached Figure Description

[0036] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of a process for the resource utilization of bromine from concentrated seawater that produces its own acids and alkalis. Detailed Implementation

[0038] To make the technical problems, technical solutions, and technical effects of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0039] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0040] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0041] In the description of the embodiments of this utility model, it should be noted that the terms "inner", "outer", "upper", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the utility model product is usually placed when in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0042] Example 1

[0043] like Figure 1 As shown, this embodiment provides a concentrated seawater bromine extraction resource utilization system that produces its own acids and alkalis, including an air-blowing seawater bromine extraction system and a bipolar membrane acid and alkali production system configured in parallel and coupled.

[0044] The air-blowing seawater bromine extraction system includes an acidification oxidation unit, a blowing unit, an absorption unit, a secondary oxidation unit, and a distillation unit connected in sequence. The air-blowing seawater bromine extraction system also includes a neutralization treatment unit. The neutralization treatment unit is connected upstream to the absorption unit, and a discharge port is provided downstream of the neutralization treatment unit. The discharge port of the distillation unit is connected to a single-element bromine collection unit, and the distillation port of the distillation unit is connected to the acidification oxidation unit through a pipeline.

[0045] The bipolar membrane acid and alkali production system includes a pretreatment unit, a concentration unit, a bipolar membrane electrodialysis unit, an evaporation unit, and a sodium hydroxide collection unit connected in sequence. The reflux port of the bipolar membrane electrodialysis unit is connected to the concentration unit through a pipeline. The acid outlet of the bipolar membrane electrodialysis unit is connected to the acidification and oxidation unit. The alkali outlet of the bipolar membrane electrodialysis unit is divided into two pipelines, one of which is connected to the evaporation unit and the other of which is connected to the neutralization treatment unit through a pipeline.

[0046] The concentrated seawater pool is connected to the inlet of the acidification and oxidation unit and the inlet of the pretreatment unit via pipelines.

[0047] The acidification oxidation unit includes an oxidation tower and a desorption tower, while the secondary oxidation unit is a packed tower.

[0048] The concentration unit is either a concentrated electrodialysis device or a reverse osmosis device.

[0049] Specifically, by configuring a bipolar membrane acid and alkali production system and an air-blowing seawater bromine extraction process system in parallel and coupled, while ensuring the relative independence of the two process systems, a portion of the concentrated seawater that has not been acidified and oxidized is used as the feed water for the bipolar membrane system. The acid and alkali produced by the bipolar membrane system are recycled to the acidification, oxidation, and neutralization of the bromine extraction mother liquor in the bromine extraction process system. This achieves the self-production and use of acid and alkali for the seawater bromine extraction process, while also producing sodium hydroxide, a product with high economic value, as a byproduct.

[0050] The acid and alkali products produced by the bipolar membrane electrodialysis acid and alkali production system meet the acid and alkali requirements of the bromine extraction process in terms of both quantity and quality. Depending on the specific circumstances, surplus acid and alkali products can also be upgraded and sold externally, resulting in good economic benefits.

[0051] Example 2

[0052] This embodiment provides a method for the resource recovery of bromine from concentrated seawater that generates its own acids and alkalis, using a concentrated seawater bromine recovery system that generates its own acids and alkalis as described in Example 1. It includes a parallel-coupled air-blowing seawater bromine recovery process and a bipolar membrane acid and alkali production process.

[0053] The process of bromine extraction from seawater using the air blowing method is as follows:

[0054] A1. In the acidification and oxidation unit, the concentrated bromine-containing seawater is first acidified with acid to adjust its pH value to acidic.

[0055] A2. Next, chlorine gas is introduced into the oxidation tower of the acidification oxidation unit to oxidize the bromide ions in the concentrated seawater into elemental bromine.

[0056] A3. Then, elemental bromine is blown out of the desorption tower of the acidification oxidation unit with air. After being absorbed by the acid absorbent in the absorption tower of the absorption unit, the elemental bromine is reduced to bromide ions and enriched in the absorption liquid. The absorption liquid enriched with bromide ions is then subjected to secondary oxidation by chlorine gas introduced in the middle of the secondary oxidation unit to generate free bromine. Finally, the free bromine is condensed in the distillation unit to obtain elemental bromine, and the mother liquor of the distillation is returned to the acidification oxidation unit for reuse.

[0057] The bipolar membrane acid and alkali production process is as follows:

[0058] B1. Take a portion of the untreated concentrated seawater and pre-treat it in a pretreatment unit for hardening removal and desalination to reduce the salt concentration and Ca content in the concentrated seawater. 2+ Mg 2+ Once the impurity content reaches the requirements for bipolar membrane feed water, the concentrated seawater is further concentrated using the concentration unit.

[0059] B2. Then, the required acid and base are prepared by a bipolar membrane electrodialysis unit.

[0060] B3. The brine produced by the bipolar membrane electrodialysis unit is returned to the concentration unit for recycling to reduce wastewater discharge; the acid produced by the bipolar membrane electrodialysis unit is recycled to the acidification and oxidation unit of the air-blowing seawater bromine extraction system to adjust the pH of the seawater.

[0061] B4. A portion of the alkali produced by the bipolar membrane electrodialysis unit is returned to the neutralization treatment unit of the air-blowing bromine extraction system to neutralize the acidic bromine extraction mother liquor, ensuring it meets discharge standards. Any remaining alkali produced by the bipolar membrane electrodialysis unit can be concentrated in the evaporation unit to prepare sodium hydroxide, which can then be collected and reused in other process sections of the plant.

[0062] Specifically, this scheme designs a bipolar membrane acid-base generation system and an air-blowing seawater bromine extraction system in parallel. Without affecting the air-blowing method for seawater bromine extraction, the parallel bipolar membrane acid-base generation system can produce acid and alkali products that meet the requirements of the bromine extraction process, achieving resource recycling of seawater from multiple perspectives. Simultaneously, the parallel design between the bipolar membrane acid-base generation system and the seawater bromine extraction system effectively avoids the impact of oxidizing substances generated during bromine extraction on the bipolar membrane system, playing a positive role in extending the service life of the bipolar membrane system.

[0063] In step B1, in the pretreatment section of the bipolar membrane acid and alkali production process, hardening can be removed by chemical precipitation, nanofiltration, and ion exchange. When chemical precipitation is used for hardening removal, the resulting acid is a mixture of sulfuric acid and hydrochloric acid; when NF is used for hardening removal, chloride ions and sulfate ions can be separated simultaneously, and the resulting acid is mainly hydrochloric acid.

[0064] Example 3

[0065] This embodiment provides a concentrated seawater bromine extraction resource utilization system that produces its own acids and alkalis.

[0066] In a bromine extraction project with a production scale of 1500 tons / year, continuous production is adopted, with 8000 hours of operation per year. Concentrated seawater from the thermal desalination process is used as raw material. The bromine content in the concentrated seawater is 80-130 ppm, with the specific content fluctuating with the season; the water temperature is 45-48℃.

[0067] In the bromine extraction section of seawater using the air blowing method, the designed treatment capacity of concentrated seawater is 2500–3000 m³ / h. After water intake, the concentrated seawater is acidified using hydrochloric acid produced in the bipolar membrane electrodialysis acid-alkali production section, controlling the seawater pH value to around 3–4. Chlorine gas is then introduced into the oxidation tower of the acidification unit, with the chlorine-to-available bromine mass ratio controlled between 1.2 and 1.8, oxidizing bromide ions to elemental bromine. A blower or other equipment capable of achieving the same effect is used to blow the bromine out in the desorption tower. The bromine-extracted seawater is then neutralized using liquid alkali from the bipolar membrane acid-alkali production section, controlling the seawater pH value to around 6–9, meeting wastewater discharge standards. The bromine is then absorbed by the H2SO3 acid mist in the absorption tower. The mass ratio of sulfur to available chlorine is controlled between 0.35 and 0.55. At this time, the bromine is reduced to bromide ions. The bromide-rich absorption liquid is then oxidized again by chlorine gas introduced in the middle of the packed tower, releasing bromine. Finally, elemental bromine is obtained by distillation and condensation. The mother liquor from the distillation is returned to the acidification unit to recover bromine and acidity.

[0068] In the concentrated seawater bipolar membrane acid and alkali production section, the designed intake of concentrated seawater is 8–10 m³ / h. After intake, the temperature of the concentrated seawater is first lowered to approximately room temperature using a heat exchanger. Then, suspended solids are removed through sand filtration and ultrafiltration, followed by hardness removal using two-stage nanofiltration (NF) or chemical precipitation and ion exchange resin equipment. Next, high-pressure reverse osmosis or electrodialysis is used to concentrate the TDS of the nanofiltration permeate to between 8–11%. The concentrate then enters the bipolar membrane unit to prepare acids and alkalis with a concentration of 1–3 mol / L. The generated acid is used in the bromine extraction acidification unit, and the generated alkali is used in the neutralization treatment of the bromine extraction mother liquor. Depending on the specific acid and alkali usage and the company's own wishes, any surplus alkali liquid can be evaporated and concentrated to prepare caustic soda flakes, which can be reused in other process sections of the plant.

[0069] By coupling a bipolar membrane acid-base production system into the bromine extraction process, the use of concentrated sulfuric acid can be reduced by 2200-2500 tons / year, and the use of 32% liquid alkali can be reduced by 1800-2100 tons / year. The overall investment payback period for the system is approximately 2-3 years.

Claims

1. A concentrated seawater bromine extraction resource utilization system that generates its own acid and alkali, characterized in that, This includes a parallel-coupled air-blowing seawater bromine extraction system and a bipolar membrane acid and alkali production system; The air-blowing seawater bromine extraction system includes an acidification oxidation unit, a blowing unit, an absorption unit, a secondary oxidation unit, and a distillation unit connected in sequence. The air-blowing seawater bromine extraction system also includes a neutralization treatment unit. The upstream of the neutralization treatment unit is connected to the absorption unit, and the downstream of the neutralization treatment unit is provided with a discharge port. The discharge port of the distillation unit is connected to a single-element bromine collection unit, and the distillation port of the distillation unit is connected to the acidification oxidation unit through a pipeline.

2. The concentrated seawater bromine extraction resource utilization system for self-producing acids and alkalis according to claim 1, characterized in that, The bipolar membrane acid and alkali production system includes a pretreatment unit, a concentration unit, a bipolar membrane electrodialysis unit, an evaporation unit, and a sodium hydroxide collection unit connected in sequence.

3. The concentrated seawater bromine extraction resource utilization system for self-producing acids and alkalis according to claim 2, characterized in that, The reflux port of the bipolar membrane electrodialysis unit is connected to the concentration unit through a pipe, the acid outlet of the bipolar membrane electrodialysis unit is connected to the acidification and oxidation unit, and the alkali outlet of the bipolar membrane electrodialysis unit is divided into two pipes, one of which is connected to the evaporation unit and the other of which is connected to the neutralization treatment unit through a pipe.

4. The concentrated seawater bromine extraction resource utilization system for self-producing acids and alkalis according to claim 3, characterized in that, The concentrated seawater pool is connected to the inlet of the acidification and oxidation unit and the inlet of the pretreatment unit via pipelines.

5. The concentrated seawater bromine extraction resource utilization system for self-producing acids and alkalis according to claim 4, characterized in that, The acidification oxidation unit includes an oxidation tower and a desorption tower, and the secondary oxidation unit is a packed tower.

6. The concentrated seawater bromine extraction resource utilization system for self-producing acids and alkalis according to claim 5, characterized in that, The concentration unit is a concentrated electrodialysis device.

7. The concentrated seawater bromine extraction resource utilization system for self-producing acids and alkalis according to claim 5, characterized in that, The concentration unit is a reverse osmosis device.

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