Method for extracting bromine from seawater

Abstract

The invention relates to the technical field of seawater bromine extraction, in particular to a seawater bromine extraction method which comprises the following steps: an acidification process, an oxidation process, a blowing and sucking process and a distillation and condensation process so as to prepare industrial bromine. Preparing an acid raw material and an alkali raw material by using a bipolar membrane device; acidifying the seawater with an acid raw material to form a first mixed solution; oxidizing the first mixed solution by using chlorine gas to form a second mixed solution, and enabling the second mixed solution to enter a blow-off tower; blowing free bromine in the second mixed solution into the absorption tower through a blow-off tower, and remaining blown solution; reacting the free bromine in the absorption tower to obtain a finished solution; the finished liquid enters a distillation tower and is reduced by chlorine to obtain gaseous bromine simple substance, and the gaseous bromine simple substance is condensed, separated and rectified to obtain industrial bromine. The technical problem of low bromine extraction efficiency in traditional construction is solved, and the efficiency of extracting bromine from low-concentration seawater is improved.

Description

Technical Field

[0001] The invention relates to the technical field of extracting bromine from seawater, and in particular to a method for extracting bromine from seawater. Background Art

[0002] Bromine is an important chemical raw material, which is widely used in flame retardants, fire extinguishing agents, refrigerants, photosensitive materials, medicines, pesticides, oil fields and other industries. At present, the production of bromine in my country mainly comes from underground brine and seawater. Because underground brine is non-renewable and is increasingly depleted due to over-exploitation, it is not conducive to the sustainable development of my country's bromine industry. At present, bromine extraction from seawater faces problems such as low seawater concentration, low bromine extraction efficiency and waste of brine resources. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the related art. To this end, the present invention provides a method for extracting bromine from seawater, which solves the technical problem of low bromine extraction efficiency in traditional construction and improves the efficiency of extracting bromine from low-concentration seawater.

[0004] The present invention provides a method for extracting bromine from seawater, comprising an acidification process, an oxidation process, a blowing and suction process, and a distillation and condensation process, thereby preparing industrial bromine; Before the acidification process, the process also includes preparing acid raw materials and alkali raw materials by using a bipolar membrane device; The acidification process comprises: Acidifying seawater using the acid raw material to form a first mixed solution; The oxidation process comprises: oxidizing the first mixed liquid using chlorine gas to form a second mixed liquid, and then the second mixed liquid enters a blow-out tower; The blowing and suction process comprises: The free bromine in the second mixed liquid is blown into the absorption tower through the blow-out tower and the remaining blow-out liquid is obtained; The post-blowing liquid enters the brine pool, and then the alkali raw material is added to the brine pool to treat the post-blowing liquid; The free bromine reacts with sulfur dioxide and water in the absorption tower to obtain a finished liquid, wherein the finished liquid includes hydrobromic acid; The distillation and condensation process comprises: The finished liquid enters the distillation tower and is then reduced by chlorine to obtain gaseous bromine. The gaseous bromine is then condensed, separated and distilled to obtain industrial bromine.

[0005] A further improvement of the method for extracting bromine from seawater of the present invention is that the blowing tower, the absorption tower and the foam catching tower are three-tower connected structures, the bottoms of the absorption tower and the foam catching tower are connected to a finished liquid pool, and the blowing and suction process further includes: Gaseous sulfur dioxide and water are introduced into the absorption tower, and then free bromine reacts with sulfur dioxide and water to generate hydrogen bromide and sulfuric acid. Hydrogen bromide is absorbed by liquid water to form hydrobromic acid. At the same time, sulfuric acid and liquid water are mixed to form a sulfuric acid aqueous solution. Hydrobromic acid, sulfuric acid aqueous solution and liquid water are collected to form a finished liquid and enter a finished liquid pool; The tail gas from the absorption tower enters the foaming tower. The tail gas from the absorption tower includes sulfur dioxide and misty hydrobromic acid. The foaming tower recovers the hydrobromic acid and flows into the finished liquid pool. The exhaust gas from the foam capture tower enters the blow-out tower again through the induced draft fan.

[0006] A further improvement of the method for extracting bromine from seawater of the present invention is that it also includes a sulfur dioxide supply device; The sulfur dioxide supply equipment includes a sulfur pallet conveying module, a bag grabbing and breaking module and a feeding module. The bagged sulfur is conveyed to the bag grabbing and breaking module by the sulfur pallet conveying module, and then the bag grabbing and breaking module grabs the corresponding bagged sulfuric acid to the feeding module, and then the bag grabbing and breaking module opens the packaging bag to allow the sulfur to enter the feeding module, and then the feeding module oxidizes the sulfur into sulfur dioxide and supplies it to the absorption tower.

[0007] A further improvement of the method for extracting bromine from seawater of the present invention is that the brine pool is provided with an online analyzer for sulfur dioxide content, and the online analyzer for sulfur dioxide content is connected to the sulfur dioxide supply device; The sulfur dioxide content in the brine pool is tested by the sulfur dioxide content online analyzer. When it is detected that the sulfur dioxide content exceeds a set threshold, the sulfur dioxide content online analyzer feeds back to the feeding module, and then the feeding module reduces the sulfur feeding amount.

[0008] A further improvement of the method for extracting bromine from seawater of the present invention is that a control system is also provided, which is connected to an online sulfur dioxide content analyzer, a bipolar membrane device, a blow-out tower, an absorption tower, a brine tank, a finishing liquid tank and a distillation tower.

[0009] A further improvement of the method for extracting bromine from seawater of the present invention is that the distillation and condensation step further comprises: The finished liquid is preheated, and the preheated finished liquid enters the distillation tower from the top of the distillation tower. At the same time, water vapor and chlorine are introduced into the bottom of the distillation tower. The hydrobromic acid, water vapor and chlorine in the finished liquid react in the packing section of the distillation tower to obtain gaseous bromine elemental substance, and then the gaseous bromine elemental substance and water vapor are discharged from the top of the distillation tower, and then industrial bromine is obtained through condensation, separation and distillation operations.

[0010] A further improvement of the method for extracting bromine from seawater of the present invention is that a condenser and a separator are further provided at the top of the distillation tower, and the top temperature of the distiller is 85-95°C; The gaseous bromine element and water vapor are discharged from the top of the distillation tower and enter the condenser, where they are condensed to form liquid bromine and bromine water. The liquid bromine and bromine water then enter the separator and are separated into layers. The liquid bromine is discharged from the bottom of the separator and subjected to rectification operation to obtain industrial bromine; The bromine water is passed from the separator into the distillation tower, and the bromine water enters the distillation tower from the top of the distillation tower.

[0011] A further improvement of the method for extracting bromine from seawater of the present invention is that the condenser has an exhaust port, and the top of the separator has an exhaust port, and the exhaust port and the exhaust port are connected to a tail gas recovery tower, through which the tail gas in the distillation tower, the condenser and the separator is processed.

[0012] A further improvement of the method for extracting bromine from seawater of the present invention is that the acid raw material is hydrochloric acid and the alkali raw material is sodium hydroxide.

[0013] The further improvement of the method for extracting bromine from seawater of the present invention is that the concentration of seawater is 2 to 6 degrees Baume, and the bromine content in the seawater is 0.05 to 0.07 g / L; In the acidification process, the pH of the first mixed solution is 3 to 3.5; In the oxidation process, the amount of chlorine introduced is 1.1~1.25 times the bromine content in seawater.

[0014] The raw materials required for the acidification and neutralization processes in the present invention are all self-made using a bipolar membrane device, thereby reducing the risks of acid and alkali storage and transportation; in the present method, automatic supply of sulfur dioxide can be achieved by arranging a sulfur dioxide supply device, and by connecting the sulfur dioxide supply device to an analyzer and arranging a control system, the supply of sulfur dioxide and the acidification and oxidation processes of seawater can be automatically controlled according to the detection results, thereby achieving automatic control of each process during bromine extraction and improving the production efficiency of bromine.

[0015] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 The present invention provides a flow chart of a method for extracting bromine from seawater. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0019] Combine the following Figure 1 The invention discloses a method for extracting bromine from seawater, which comprises an acidification process, an oxidation process, a blowing and suction process, and a distillation and condensation process, thereby preparing industrial bromine. Prior to the acidification process, the method also comprises preparing acid raw materials and alkali raw materials by using a bipolar membrane device.

[0020] Specifically, the acidification process includes: using the acid raw material to acidify seawater to form a first mixed liquid.

[0021] Specifically, the oxidation process includes: oxidizing the first mixed liquid with chlorine gas to form a second mixed liquid, and then the second mixed liquid enters the blowing tower; Specifically, the blowing and absorbing process includes: blowing free bromine in the second mixed liquid into the absorption tower through the blowing tower and leaving the remaining post-blowing liquid; Specifically, the post-blowing liquid enters a brine pool, and then an alkali raw material is added to the brine pool to treat the post-blowing liquid; free bromine reacts with sulfur dioxide and water in an absorption tower to obtain a finished liquid, and the finished liquid includes hydrobromic acid; Specifically, the distillation and condensation process includes: the finished liquid enters the distillation tower, and is then reduced by chlorine to obtain gaseous bromine elemental substance, and then the gaseous bromine elemental substance is condensed, separated and distilled to obtain industrial bromine.

[0022] Specifically, the method for extracting bromine from seawater of the present invention is provided with a sulfur dioxide supply device; the sulfur dioxide supply device includes a sulfur tray conveying module, a bag grabbing and breaking module and a feeding module, the bagged sulfur is conveyed to the bag grabbing and breaking module by the sulfur tray conveying module, and then the bag grabbing and breaking module grabs the corresponding bagged sulfuric acid to the feeding module, and then the bag grabbing and breaking module opens the packaging bag to allow the sulfur to enter the feeding module, and then the feeding module oxidizes the sulfur into sulfur dioxide and supplies it to the absorption tower, and the feeding module has a sulfur incinerator, and the sulfur is oxidized into sulfur dioxide by the sulfur incinerator.

[0023] Specifically, seawater is transported through a seawater pipeline. A first transfer box and a second transfer box are provided at the front end of the seawater pipeline. The second transfer box is connected to the blowing tower. The seawater is acidified in the first transfer box and oxidized in the second transfer box. Each process is connected by a delivery pump.

[0024] Specifically, the delivery pump, the first transfer box, the second transfer box, the bipolar membrane device, the blowing tower, the absorption tower, the foaming tower, the brine pool, the finishing liquid pool, the distillation tower, the condenser, the separator, and the tail gas recovery tower are controlled and connected to the control system.

[0025] Preparation of acid raw materials and alkali raw materials: The bipolar membrane device prepares acid raw materials and alkali raw materials through industrial salt. The acid raw material is hydrochloric acid, and the alkali raw material is sodium hydroxide. The hydrochloric acid and sodium hydroxide are made by the bipolar membrane device, which avoids the transportation risk of the acid and alkali raw materials and saves transportation costs. The control system can automatically control the amount of hydrochloric acid added to the first transfer box and the amount of sodium hydroxide added to the brine pool according to demand.

[0026] Acidification process: acidifying seawater using the acid raw material to form a first mixed solution.

[0027] The first transfer box is provided with a pH meter, a stirring paddle, and a seawater concentration tester. The control system automatically controls the amount of hydrochloric acid added according to the detection data of the pH meter to adjust the pH of the seawater in the first transfer box to 3-3.5; the control system detects the concentration of the seawater according to the seawater concentration tester.

[0028] Specifically, the concentration of seawater is 2 to 6 degrees Baume.

[0029] Oxidation process: The first mixed liquid is oxidized by chlorine gas to form a second mixed liquid, and then the second mixed liquid enters the blowing tower.

[0030] The second transfer box is equipped with a stirring paddle and an online analyzer for the total bromine and chlorine value of materials. The acidified seawater is oxidized in the second transfer box to oxidize the bromide ions in the seawater into Br2. The amount of chlorine added is 1.1 to 1.25 times the bromide ion content. The chemical reaction of this process is: The oxidation reaction in this process is the key to the entire bromine extraction method. If the oxidation reaction is not sufficient, the oxidation rate of bromide ions in seawater will be low, resulting in a low extraction rate and a waste of bromine resources. Therefore, an online analyzer of the total bromine-chlorine value material is used to detect the chlorine ratio, strictly control the amount of chlorine added and the reaction residence time, and ensure that the chlorine and seawater are fully mixed and reacted.

[0031] In a specific implementation case, the concentration of seawater is 3 degrees Baume, the bromine content in the seawater is 0.05~0.07 g / L, and when chlorine is used to oxidize the first mixed liquid to form a second mixed liquid, the amount of chlorine introduced is 1.1~1.25 times the bromine content in the first mixed liquid.

[0032] Blowing and suction process: the free bromine in the second mixed liquid is blown into the absorption tower through the blow-out tower and the remaining blow-out liquid is left; the blow-out liquid enters the brine pool, and then the alkali raw material is added to the brine pool to treat the blow-out liquid, so as to produce salt; the free bromine reacts with sulfur dioxide and water in the absorption tower to obtain a finished liquid, and the finished liquid includes hydrobromic acid and a small amount of sulfuric acid; the blow-out tower, the absorption tower and the foaming tower are three-tower connected structures, and the bottoms of the absorption tower and the foaming tower are connected to the finished liquid pool; the tail gas of the absorption tower enters the foaming tower, and the tail gas of the absorption tower includes sulfur dioxide and mist-like hydrobromic acid, and then the foaming tower recovers the hydrobromic acid and merges it into the finished liquid pool.

[0033] Specifically, gaseous sulfur dioxide and water are introduced into the absorption tower, and then free bromine reacts with sulfur dioxide and water to generate hydrogen bromide and sulfuric acid, hydrogen bromide is absorbed by liquid water to form hydrobromic acid, and sulfuric acid and liquid water are mixed to form a sulfuric acid aqueous solution, hydrobromic acid, sulfuric acid aqueous solution and liquid water are combined to form a finished liquid and enter a finished liquid pool; the tail gas of the absorption tower enters a foaming tower, the tail gas of the absorption tower includes sulfur dioxide and misty hydrobromic acid, the foaming tower recovers the hydrobromic acid and merges it into the finished liquid pool; the tail gas of the foaming tower enters the blowing tower again through the induced draft fan.

[0034] Therefore, the brine pool may contain sulfur dioxide that has not participated in the reaction in the absorption tower. The sulfur dioxide content in the brine pool can be detected to facilitate the control of the amount of sulfur dioxide added.

[0035] Specifically, the brine pool is provided with an online sulfur dioxide content analyzer, which is connected to the sulfur dioxide supply device; the sulfur dioxide content in the brine pool is tested by the online sulfur dioxide content analyzer, and when it is detected that the sulfur dioxide content exceeds a set threshold, the online sulfur dioxide content analyzer feeds back to the feeding module, and then the feeding module reduces the sulfur feed amount.

[0036] Specifically, the chemical reaction formula of the absorption tower process is: ; As can be seen from the reaction formula, the amount of sulfur dioxide introduced affects the absorption of bromine. If the amount of SO2 added is too little, the free bromine is not absorbed thoroughly and cannot be completely reduced; if the amount added is too much, SO2 cannot be fully utilized, and the bromine blowing rate in the blowing tower will be reduced, the blowing cost will be increased, and resources will be wasted. Therefore, the present invention uses an online analyzer for sulfur dioxide content. The online analyzer for sulfur dioxide content determines the free chlorine content in the waste liquid by using the red depth of methyl red, indirectly determines whether sulfur dioxide is excessive, detects the content of SO2 in the absorbed tail gas, and adjusts the amount of sulfur added to the incinerator in real time according to the tail gas content to achieve process optimization.

[0037] The second mixed liquid is evenly distributed from the top of the blowing tower and flows through the packing layer of the blowing tower from top to bottom. The free bromine in the second mixed liquid is blown into the air from the bottom of the tower by the fan for analysis, and the liquid containing free bromine is blown out from the top of the tower into the absorption tower. The remaining liquid is discharged from the bottom of the blowing tower through the liquid seal pipe and flows into the brine pool of the lower level. The bipolar membrane device adds sodium hydroxide into the brine pool for salt production.

[0038] Preferably, the packing layer of the blowing tower in this process is a new type of regular packing and stepped ring packing which is light in weight, large in capacity, low in pressure drop, high in specific surface area, easy to replace and has good chemical stability, so as to reduce the bromine content of the liquid after blowing.

[0039] Specifically, when the bromine content in the finished liquid reaches 50-70 g / L, the overflow is discharged from the bottom of the absorption tower into the finished liquid pool.

[0040] Distillation and condensation process: The finished liquid enters the distillation tower and is then reduced by chlorine to obtain gaseous bromine. The gaseous bromine is then condensed, separated and distilled to obtain industrial bromine.

[0041] Specifically, the finished liquid is preheated, and the preheated finished liquid enters the distillation tower from the top of the distillation tower, and water vapor and chlorine are introduced into the bottom of the distillation tower. The hydrobromic acid, water vapor and chlorine in the finished liquid react in the packing section of the distillation tower to obtain gaseous bromine elemental substance, and then the gaseous bromine elemental substance and water vapor are discharged from the top of the distillation tower, and then industrial bromine is obtained through condensation, separation and distillation operations.

[0042] Specifically, a condenser and a separator are also provided at the top of the distillation tower, and the top temperature of the distillation tower is 85-95°C; gaseous bromine element and water vapor are discharged from the top of the distillation tower and enter the condenser, where they are condensed to form liquid bromine and bromine water, and then the liquid bromine and bromine water enter the separator and are stratified in the separator; the liquid bromine is discharged from the bottom of the separator and industrial bromine is obtained through distillation operation; the bromine water is passed from the separator into the distillation tower, and the bromine water enters the distillation tower from the top of the distillation tower.

[0043] Specifically, the condenser has an exhaust port, and the top of the separator has an exhaust port, the exhaust port and the exhaust port are connected to a tail gas recovery tower, and the tail gas in the distillation tower, the condenser and the separator is processed through the tail gas recovery tower.

[0044] Specifically, the finished liquid enters from the top of the distillation tower and is sprayed down from the top of the packing section of the distillation tower. Steam and chlorine are introduced from the bottom of the distillation tower for countercurrent replacement. The bromine molecules replaced by oxidation are vaporized and discharged from the upper part of the tower together with the water vapor. The top temperature of the distillation tower is controlled to 85~95℃ by steam addition. The bromine vapor out of the tower is mixed with the water vapor and condensed into liquid bromine and bromine water through the condenser. Liquid bromine and bromine water have different densities and are automatically separated in the separator. The lower layer is liquid bromine with higher density, which is discharged from the lower port of the separator and then distilled to obtain industrial bromine; the upper layer is saturated bromine water with lower density, which is extracted from the middle of the separator and returned to the distillation tower. Uncondensed gas is discharged from the condenser exhaust port and the top of the separator. The uncondensed gas contains some excess chlorine and uncondensed bromine, etc., which enter the tail gas recovery tower to recover the chlorine and bromine therein. The chemical reaction formula of this process is as follows: .

[0045] Tail gas recovery: Specifically, the tail gas recovery tower processes non-condensable gases discharged from the distillation tower, condenser and separator, and the main substances are Br2, Cl2 and SO2. In order to ensure that the tail gas of the distillation process meets the emission standards, the acid washing recovery device and the alkali washing recovery device are used for absorption. The acid washing recovery device uses HBr-containing mother liquor as the absorption liquid to absorb Br2, Cl2 and SO2 in the gas. The absorption liquid (i.e., HBr mother liquor) is discharged from the bottom of the acid washing recovery device and enters the distillation tower. The alkali washing recovery device uses sodium hydroxide solution as the absorption liquid, which is added through the top spray of the alkali washing recovery device to absorb part of the tail gas remaining after acid washing, and is discharged from the bottom of the alkali washing recovery device to the alkali liquid circulation tank, and then pumped to the alkali washing recovery device for cyclic absorption. The original alkali washing absorption tower in the traditional process is changed from a one-stage absorption to a two-stage absorption, which increases the absorption and utilization rate of the tail gas; the alkali absorption liquid is self-flowing to the alkali washing recovery device for spraying using the liquid level difference, and the absorbed alkali absorption liquid enters the alkali liquid circulation tank, and then pumped to the top buffer tank of the alkali washing recovery device to achieve cyclic absorption. Since the alkali absorption liquid circulation pipeline is DN50 in diameter, and the spray pipeline is DN25 in diameter, the amount of alkali absorption liquid circulating in the buffer tank is greater than the gravity flow rate, which can ensure that the alkali absorption liquid in the buffer tank is sufficient. When the alkali absorption liquid in the tank is full, it overflows back to the alkali liquid circulation tank through the bypass overflow port. The present invention utilizes the liquid level difference to achieve the alkali washing recovery device to maintain normal operation after power failure, which can avoid the problem of emergency power failure before the transformation, the circulation pump stops running, causing a large amount of exhaust gas to be emptied and pollute the air, and can also avoid the loss of some products.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for extracting bromine from seawater, characterized in that: It includes an acidification process, an oxidation process, a blowing and suction process, and a distillation and condensation process, thereby preparing industrial bromine; Before the acidification process, the process also includes preparing acid raw materials and alkali raw materials by using a bipolar membrane device; The acidification process comprises: Acidifying seawater using the acid raw material to form a first mixed solution; The oxidation process comprises: oxidizing the first mixed liquid using chlorine gas to form a second mixed liquid, and then the second mixed liquid enters a blow-out tower; The blowing and suction process comprises: The free bromine in the second mixed liquid is blown into the absorption tower through the blow-out tower and the remaining blow-out liquid is obtained; The post-blowing liquid enters the brine pool, and then the alkali raw material is added to the brine pool to treat the post-blowing liquid; The free bromine reacts with sulfur dioxide and water in the absorption tower to obtain a finished liquid, wherein the finished liquid includes hydrobromic acid; The distillation and condensation process comprises: The finished liquid enters the distillation tower and is then reduced by chlorine to obtain gaseous bromine. The gaseous bromine is then condensed, separated and distilled to obtain industrial bromine.

2. The method for extracting bromine from seawater according to claim 1, characterized in that: The blowing tower, the absorption tower and the foam catching tower are three-tower connected structures, and the bottoms of the absorption tower and the foam catching tower are connected to a finished liquid pool. The blowing and suction process also includes: Gaseous sulfur dioxide and water are introduced into the absorption tower, and then free bromine reacts with sulfur dioxide and water to generate hydrogen bromide and sulfuric acid. Hydrogen bromide is absorbed by liquid water to form hydrobromic acid. At the same time, sulfuric acid and liquid water are mixed to form a sulfuric acid aqueous solution. Hydrobromic acid, sulfuric acid aqueous solution and liquid water are collected to form a finished liquid and enter a finished liquid pool; The tail gas from the absorption tower enters the foaming tower. The tail gas from the absorption tower includes sulfur dioxide and misty hydrobromic acid. The foaming tower recovers the hydrobromic acid and flows into the finished liquid pool. The exhaust gas from the foam capture tower enters the blow-out tower again through the induced draft fan.

3. The method for extracting bromine from seawater according to claim 2, characterized in that: It also includes sulfur dioxide supply equipment; The sulfur dioxide supply equipment includes a sulfur pallet conveying module, a bag grabbing and breaking module and a feeding module. The bagged sulfur is conveyed to the bag grabbing and breaking module by the sulfur pallet conveying module, and then the bag grabbing and breaking module grabs the corresponding bagged sulfuric acid to the feeding module, and then the bag grabbing and breaking module opens the packaging bag to allow the sulfur to enter the feeding module, and then the feeding module oxidizes the sulfur into sulfur dioxide and supplies it to the absorption tower.

4. The method for extracting bromine from seawater according to claim 3, characterized in that: The brine pool is provided with an online sulfur dioxide content analyzer, which is connected to the sulfur dioxide supply device; The sulfur dioxide content in the brine pool is tested by the sulfur dioxide content online analyzer. When it is detected that the sulfur dioxide content exceeds a set threshold, the sulfur dioxide content online analyzer feeds back to the feeding module, and then the feeding module reduces the sulfur feeding amount.

5. The method for extracting bromine from seawater according to claim 4, characterized in that: A control system is also provided, which is connected to an online sulfur dioxide content analyzer, a bipolar membrane device, a blow-out tower, an absorption tower, a brine pool, a finished liquid pool and a distillation tower.

6. The method for extracting bromine from seawater according to claim 1, characterized in that: The distillation and condensation process also includes: The finished liquid is preheated, and the preheated finished liquid enters the distillation tower from the top of the distillation tower. At the same time, water vapor and chlorine are introduced into the bottom of the distillation tower. The hydrobromic acid, water vapor and chlorine in the finished liquid react in the packing section of the distillation tower to obtain gaseous bromine elemental substance, and then the gaseous bromine elemental substance and water vapor are discharged from the top of the distillation tower, and then industrial bromine is obtained through condensation, separation and distillation operations.

7. The method for extracting bromine from seawater according to claim 6, characterized in that: The top of the distillation tower is also equipped with a condenser and a separator, and the top temperature of the distiller is 85~95℃; The gaseous bromine element and water vapor are discharged from the top of the distillation tower and enter the condenser, where they are condensed to form liquid bromine and bromine water. The liquid bromine and bromine water then enter the separator and are separated into layers. The liquid bromine is discharged from the bottom of the separator and subjected to rectification operation to obtain industrial bromine; The bromine water is passed from the separator into the distillation tower, and the bromine water enters the distillation tower from the top of the distillation tower.

8. The method for extracting bromine from seawater according to claim 7, characterized in that: The condenser has an exhaust port, and the top of the separator has an exhaust port, and the exhaust port and the exhaust port are connected to a tail gas recovery tower, and the tail gas in the distillation tower, the condenser and the separator is processed through the tail gas recovery tower.

9. The method for extracting bromine from seawater according to claim 1, characterized in that: The acid raw material is hydrochloric acid, and the alkali raw material is sodium hydroxide.

10. The method for extracting bromine from seawater according to claim 1, characterized in that: The concentration of seawater is 2 to 6 degrees Baume, and the bromine content in seawater is 0.05 to 0.07 g / L; In the acidification process, the pH of the first mixed solution is 3 to 3.5; In the oxidation process, the amount of chlorine introduced is 1.1~1.25 times the bromine content in seawater.

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