A bromine production system based on multi-stage alkali absorption

Abstract

The utility model relates to the technical field of bromine production, especially based on multistage lye absorption's bromine production system. The system includes blowing tower, the foam trap, the absorption tower, lye tank and sodium sulfite solution tank, wherein, absorption tower middle part adds the lye injection layer, and blowing tower top and absorption tower lye injection layer all are connected to lye tank, and sodium sulfite solution tank is connected to the upper layer spray pipeline of foam trap, and absorption tower bottom and foam trap bottom are connected, and absorption tower-foam trap connecting section is connected to absorption tower top circulating spray pipeline and tail gas absorption tower top through complete liquid pump, and tail gas absorption tower bottom is connected to foam trap. The utility model utilizes sodium sulfite and bromine reaction, absorbs the residual bromine not absorbed in the foam trap, thereby improves the operation efficiency and output of device.

Description

Technical Field

[0001] This utility model relates to the field of bromine production technology, and in particular to a bromine production system based on multi-stage alkaline solution absorption. Background Technology

[0002] Since its development in 1907, the seawater bromine extraction process has become increasingly mature, and with continuous technological development, it has made significant progress. Technological advancements in both equipment and processes have supported the continuous progress of seawater bromine extraction.

[0003] During production, the oxidized brine enters a blow-out tower, where elemental bromine is separated from the brine via air blowing. The bromine-containing gas reacts with sulfur dioxide and fresh water spray to produce hydrobromic acid and sulfuric acid (formula: Br2 + SO2 + 2H2O → 2HBr + H2SO4). These small droplets containing hydrobromic acid and sulfuric acid are absorbed and enriched in an absorption tower, condensing into liquid and eventually flowing into a finishing tank. The exhaust gas from the absorption tower enters a mist eliminator. The main function of the mist eliminator is to purify the gas and absorb residual hydrobromic acid, removing droplets and impurities from the gas separated in the absorption tower, preventing droplets from entering the circulation system and avoiding damage to the system or impact on production efficiency. The finished solution is actually a mixture of hydrobromic acid and sulfuric acid. Sulfuric acid exists as a byproduct. It participates in the distillation process along with the finished solution, but does not participate in the reaction.

[0004] Single-stage absorption towers typically achieve only 85-90% Br2 absorption, and 5-10% bromine is still lost after secondary absorption in the mist trap. Traditional processes use SO2 as a reducing agent (Br2 + SO2 + 2H2O → 2HBr + H2SO4), but sulfur prices continue to rise, and SO2 storage poses safety risks. Therefore, this invention is proposed. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a bromine production system based on multi-stage alkaline solution absorption. It utilizes the reaction of sodium sulfite with bromine to absorb the remaining unabsorbed bromine in the demister chamber, thereby improving the operating efficiency and output of the device.

[0006] The technical solution of this utility model is as follows: A bromine production system based on multi-stage alkaline absorption includes a blow-out tower, a demister chamber, an absorption tower, an alkaline tank, and a sodium sulfite solution tank. An alkaline injection layer is added in the middle of the absorption tower. The top of the blow-out tower and the alkaline injection layer of the absorption tower are both connected to the alkaline tank. The sodium sulfite solution tank is connected to the upper spray pipe of the demister chamber. The bottom of the absorption tower and the bottom of the demister chamber are connected. The absorption tower-demister chamber connection section is connected to the top circulating spray pipe (existing spray pipe) of the absorption tower and the top of the tail gas absorption tower via a liquid pump. The bottom of the tail gas absorption tower is connected to the demister chamber.

[0007] According to the preferred embodiment of this utility model, the connecting pipeline between the top of the blowing tower and the alkaline injection layer of the absorption tower and the alkaline tank is an alkaline delivery pipeline. An alkaline pump, a solenoid valve A and a flow meter A are installed on the alkaline delivery pipeline. The flow rate of the primary absorption is controlled by adjusting the opening of the solenoid valve A according to the actual production needs.

[0008] According to a preferred embodiment of this invention, the connecting pipe between the sodium sulfite solution tank and the foam trap is a sodium sulfite solution delivery pipeline. The sodium sulfite solution delivery pipeline is equipped with a sodium sulfite solution pump, a solenoid valve B, and a flow meter B. The secondary absorption improves the reabsorption efficiency of the foam trap by adjusting the opening of the solenoid valve B and adjusting the flow rate.

[0009] According to a preferred embodiment of this invention, manual valves A and B are respectively installed on the connecting pipelines between the liquid pump and the absorption tower and the tail gas absorption tower. The flow rates of the liquid pump to the absorption tower and the tail gas absorption tower are adjusted using manual valves A and B to achieve three-stage absorption.

[0010] According to a preferred embodiment of this invention, the finishing liquid pump is further connected to a finishing liquid tank, and a solenoid valve C and a flow meter C are installed on the connecting pipeline between the finishing liquid pump and the finishing liquid tank. The opening degree of the solenoid valve C is adjusted according to the actual finished liquid production volume to control the flow rate of the finished liquid.

[0011] According to a preferred embodiment of this utility model, the mist collection chamber is connected to a blower tower, which is connected to the bottom of the tail gas absorption tower. Excess gas is discharged upward through the bottom of the tail gas absorption tower, and the tail gas absorption liquid enters from the top of the tail gas absorption tower. The gas and liquid phases are absorbed by countercurrent contact. The bottom of the tail gas absorption tower is connected to the mist collection chamber, and the tail gas absorption liquid flows back to the mist collection chamber, thus achieving four-stage absorption.

[0012] The beneficial effects of this utility model are as follows: This invention adds an alkaline injection layer in the middle of the absorption tower, and an 8-10% NaOH solution for the upper spray and the connection section between the absorption tower and the mist collector. The main absorption reaction is Br2 + 2NaOH → NaBr + NaBrO + H2O, which enhances the absorption of escaped Br2. The gas-liquid countercurrent and cross-flow composite contact significantly improves the absorption efficiency. Sodium sulfite is connected to the absorption tower (reaction: Na2SO3 + Br2 + H2O → Na2SO4 + 2HBr) and the connection section between the absorption tower and the mist collector (captures residual Br2), replacing the traditional SO2 injection. The reaction efficiency is increased by 30%, and three absorption methods, namely sulfur, sodium hydroxide, and sodium sulfite, can be realized. This not only improves the absorption efficiency of the device but also reduces the production cost. Attached Figure Description

[0013] Figure 1 is a schematic diagram of the structure of this utility model.

[0014] In the diagram: 1. Blowout tower, 2. Foam trap, 3. Absorption tower, 4. Sodium sulfite solution tank, 5. Alkali tank, 6. Solenoid valve B, 7. Flow meter B, 8. Sodium sulfite solution delivery pipeline, 9. Fan, 10. Finished liquid pump, 11. Sodium sulfite solution pump, 12. Alkali pump, 13. Solenoid valve A, 14. Flow meter A, 15. Alkali delivery pipeline, 16. Tail gas absorption tower, 17. Solenoid valve C, 18. Flow meter C, 19. Manual valve A, 20. Manual valve B, 21. Finished liquid tank. Detailed Implementation

[0015] The present invention will be further described below with reference to the embodiments and accompanying drawings, but is not limited thereto.

[0016] Example 1: like Figure 1 As shown, this embodiment provides a bromine production system based on multi-stage alkali absorption, including a blow-out tower 1, a demister 2, an absorption tower 3, an alkali tank 5, and a sodium sulfite solution tank 4. An alkali injection layer is added to the middle of the absorption tower 3. The top of the blow-out tower 1 and the alkali injection layer of the absorption tower 3 are both connected to the alkali tank 5. The sodium sulfite solution tank 4 is connected to the upper spray pipe of the demister 2. The bottom of the absorption tower 3 is connected to the bottom of the demister 2. The absorption tower-demister connection section is connected to the top circulating spray pipe (existing spray pipe) of the absorption tower 3 and the top of the tail gas absorption tower 16 via a liquid pump 10. The bottom of the tail gas absorption tower 16 is connected to the demister 2.

[0017] The connecting pipeline between the top of the blowing tower 1 and the alkali injection layer of the absorption tower 3 and the alkali tank 5 is the alkali delivery pipeline 15. The alkali delivery pipeline 15 is equipped with an alkali pump 12, a solenoid valve A13 and a flow meter A14. The flow rate of the primary absorption is controlled by adjusting the opening of the solenoid valve A according to the actual production needs.

[0018] The connection between the sodium sulfite solution tank 4 and the mist collection chamber 2 is a sodium sulfite solution delivery pipeline 8. The sodium sulfite solution delivery pipeline 8 is equipped with a sodium sulfite solution pump 11, a solenoid valve B6, and a flow meter B7. The secondary absorption improves the reabsorption efficiency of the mist collection chamber by adjusting the opening of the solenoid valve B and adjusting the flow rate.

[0019] Manual valves A19 and B20 are respectively installed on the connecting pipelines of the liquid pump 10 to the absorption tower 3 and the tail gas absorption tower 16. The flow rates of the liquid to the absorption tower and the tail gas absorption tower are adjusted by manual valves A and B to achieve three-stage absorption.

[0020] The finishing liquid pump 10 is also connected to the finishing liquid tank 21. A solenoid valve C17 and a flow meter C18 are installed on the connecting pipeline between the finishing liquid pump 10 and the finishing liquid tank 21. The opening degree of the solenoid valve C17 is adjusted according to the actual production volume of the finishing liquid to control the flow rate of the finishing liquid.

[0021] The mist chamber 2 is connected to the blower tower 1 via the blower 9. The blower tower 1 is connected to the bottom of the tail gas absorption tower 16. Excess gas is discharged upward through the bottom of the tail gas absorption tower. The tail gas absorption liquid enters from the top of the tail gas absorption tower. The gas and liquid phases are in countercurrent contact for absorption. The bottom of the tail gas absorption tower 16 is connected to the mist chamber 2. The tail gas absorption liquid flows back to the mist chamber, realizing four-stage absorption.

[0022] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A bromine production system based on multi-stage alkaline solution absorption, characterized in that, It includes a blow-out tower, a condensate chamber, an absorption tower, an alkali tank, and a sodium sulfite solution tank. An alkali injection layer is added in the middle of the absorption tower. The top of the blow-out tower and the alkali injection layer of the absorption tower are both connected to the alkali tank. The sodium sulfite solution tank is connected to the upper spray pipe of the condensate chamber. The bottom of the absorption tower and the bottom of the condensate chamber are connected. The absorption tower-condensate chamber connection section is connected to the top circulating spray pipe of the absorption tower and the top of the tail gas absorption tower through a liquid pump. The bottom of the tail gas absorption tower is connected to the condensate chamber.

2. The bromine production system based on multi-stage alkaline solution absorption as described in claim 1, characterized in that, The connecting pipeline between the top of the blowing tower and the alkaline injection layer of the absorption tower and the alkaline tank is the alkaline delivery pipeline. An alkaline pump, solenoid valve A and flow meter A are installed on the alkaline delivery pipeline.

3. The bromine production system based on multi-stage alkaline solution absorption as described in claim 2, characterized in that, The connecting pipe between the sodium sulfite solution tank and the foam trap is a sodium sulfite solution delivery pipeline, which is equipped with a sodium sulfite solution pump, solenoid valve B, and flow meter B.

4. The bromine production system based on multi-stage alkaline solution absorption as described in claim 3, characterized in that, Manual valve A and manual valve B are respectively installed on the connecting pipelines of the liquid pump to the absorption tower and the tail gas absorption tower.

5. The bromine production system based on multi-stage alkaline solution absorption as described in claim 4, characterized in that, The liquid pump is also connected to a liquid tank, and a solenoid valve C and a flow meter C are installed on the connecting pipeline between the liquid pump and the liquid tank.

6. The bromine production system based on multi-stage alkaline solution absorption as described in claim 5, characterized in that, The mist collection chamber is connected to a blower tower, which is connected to the bottom of a tail gas absorption tower, and the bottom of the tail gas absorption tower is connected to the mist collection chamber.

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