Device for heating saline water by using ionic membrane caustic soda waste heat
By using the waste heat of wet chlorine to perform countercurrent heat exchange and secondary heating of brine in the production of caustic soda of ion membrane, the problem of heat loss during the washing and cooling of wet chlorine is solved, the temperature of brine and the effective utilization of energy are achieved, and the production cost is reduced.
Patent Information
- Application Number
- CN202422099884.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-28
- Publication Date
- 2025-07-11
- Estimated Expiration
- 2034-08-28
AI Technical Summary
During the production process of caustic soda in ion membrane, the heat is taken away by the circulating water during the washing and cooling process of wet chlorine, resulting in an increase in the temperature of the circulating water and an increase in the evaporation and water loss, resulting in inconvenience in production.
The filtered brine is subjected to counter-current heat exchange and secondary steam heating by the first and second heat exchangers connected by the ion membrane caustic soda waste heat is used to achieve counter-current heat exchange and secondary steam heating to make the brine temperature reach 60°C, and the heat of wet chlorine is transferred to the brine, reducing production costs and improving energy utilization efficiency.
Effectively use the heat of wet chlorine to heat brine, reduce production costs, increase the temperature of brine, ensure that the heat of wet chlorine is comprehensively utilized, and avoid the increase in the temperature of circulating water and evaporation loss.
Smart Images
Figure CN223091083U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of ion-exchange membrane caustic soda production, in particular to a device for heating brine by using the waste heat of ion-exchange membrane caustic soda. Background Art
[0002] In the ion-exchange membrane caustic soda production process, electrolyzing saturated brine (NaCl solution) can produce sodium hydroxide (NaOH, caustic soda), hydrogen (H2) and chlorine (Cl2). This process consumes a large amount of electric energy, and a considerable amount of heat is generated during the electrolysis process. The temperature of the waste heat is usually high enough to be used in other industrial processes, thereby improving energy efficiency and reducing overall energy consumption. In the production process, before the brine enters the electrolytic cell, the brine needs to be preliminarily heated to the temperature required for electrolysis.
[0003] The approximately 85°C wet chlorine gas coming out of the electrolytic cell is usually directly sent into the chlorine washing tower for washing and cooling. During the washing and cooling process of the wet chlorine gas, a large amount of its heat is carried away by the circulating water, resulting in an increase in the temperature of the circulating water and an increase in the evaporation loss of the circulating water, which is rather inconvenient to handle. Content of the Utility Model
[0004] The purpose of the utility model is to provide a device for heating brine by using the waste heat of ion-exchange membrane caustic soda, which can avoid the problem that a large amount of heat is carried away by the circulating water during the washing and cooling process of the wet chlorine gas, resulting in an increase in the temperature of the circulating water and an increase in the evaporation loss of the circulating water.
[0005] The utility model provides a device for heating brine by using the waste heat of ion-exchange membrane caustic soda, comprising:
[0006] An electrolysis workshop for electrolyzing saturated brine. The electrolysis workshop is connected to a first heat exchanger and a second heat exchanger through pipelines. The second heat exchanger is connected to a resin filter tower installed externally through a pipeline. The upper end of the resin filter tower is connected to the electrolysis workshop through a pipeline.
[0007] Preferably, the first heat exchanger and the second heat exchanger are components made of the same structure, and both are provided with a steam inlet and a steam outlet on the outside. The first heat exchanger and the second heat exchanger are also provided with a liquid inlet and a liquid outlet on the outside.
[0008] Preferably, the steam inlets at the upper ends of the first heat exchanger and the second heat exchanger are respectively connected to a steam delivery pipe, and the lower end of the steam delivery pipe is connected to the electrolysis workshop. The steam outlets of the first heat exchanger and the second heat exchanger are transported to the chlorine washing tower through a return pipeline for re-washing.
[0009] Preferably, a condensing pipe is installed at the bottom of the first heat exchanger and the second heat exchanger, and the condensing pipe is connected to the chlorine water collection tank.
[0010] Preferably, the first heat exchanger and the second heat exchanger are connected to the filtered brine tank through a pipe body, and the filtered brine tank is pumped through a filtered brine pump to the pipeline at the liquid inlet position for feeding.
[0011] Preferably, a circulation system is also arranged at the positions of the liquid inlet and the liquid outlet, and the circulation system is connected to the first heat exchanger and the second heat exchanger.
[0012] Preferably, the circulation system includes a first inlet pipe installed at the upper end of the first heat exchanger and the liquid inlet, a first outlet pipe connected to the liquid outlet, and a second outlet pipe installed at the upper end of the second heat exchanger. The other end of the first outlet pipe is installed at the liquid inlet position of the second heat exchanger. First control valves, second control valves, and third control valves are respectively installed at the upper ends of the first inlet pipe, the first outlet pipe, and the second outlet pipe.
[0013] Preferably, a first circulation pipe is arranged at the upper connection of the first inlet pipe and the first outlet pipe, and a second circulation pipe is also arranged at the upper ends of the first outlet pipe and the second outlet pipe. Fourth control valves are installed at the upper ends of the first circulation pipe and the second circulation pipe.
[0014] Preferably, a first communication pipe is arranged on the other side of the first inlet pipe and the first outlet pipe, and a fifth control valve is arranged at the upper end of the first communication pipe.
[0015] Preferably, a second communication pipe is installed at the upper ends of the first outlet pipe and the second outlet pipe. The second communication pipe connects the first outlet pipe and the second outlet pipe and is controlled by a sixth control valve arranged in the pipeline. The second control valve is installed at the front end of the second communication pipe, and a seventh control valve is installed at the other side position of the second communication pipe. The seventh control valve is installed in the pipeline of the first outlet pipe.
[0016] For a device for heating brine by using the waste heat of ion-exchange membrane caustic soda provided by an embodiment of the present invention, when it is necessary to heat the filtered brine, the filtered brine enters the first heat exchanger from the liquid inlet for heat exchange operation. The wet chlorine gas from the electrolysis workshop enters through the steam inlet and performs countercurrent heat exchange with the internal filtered brine. After the heat exchange in the first heat exchanger is completed, it is sent into the second heat exchanger for secondary steam heating, so that the temperature of the filtered brine is increased to 60 °C and enters the resin filtration tower for treatment. After the treatment is completed, it is transported to the electrolysis workshop for electrolysis utilization. The temperature of the wet chlorine gas decreases, and the heat of the wet chlorine gas steam is transferred to the filtered brine, reducing the production cost and at the same time ensuring the comprehensive utilization of the heat of the wet chlorine gas. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] To more clearly illustrate the technical solutions of the embodiments of the present utility model, the accompanying drawings required for the embodiments will be briefly introduced below. It should be understood that the following accompanying drawings only show some embodiments of the present utility model, and thus should not be regarded as a limitation of the scope. For those of ordinary skill in the art, without creative efforts, other related accompanying drawings can also be obtained based on these drawings.
[0018] Figure 1 Schematic diagram of the overall structure of the embodiment of the present utility model.
[0019] Figure 2 Schematic diagram of the installation of the first heat exchanger and the second heat exchanger in the embodiment of the present utility model.
[0020] Figure 3 Schematic diagram of the structures of the first heat exchanger and the second heat exchanger in the embodiment of the present utility model.
[0021] Figure 4 Schematic diagram of the structure of the circulation system in the embodiment of the present utility model.
[0022] Figure 5 Schematic diagram of the heat exchange process structure in the embodiment of the present utility model.
[0023] Description of the drawings: 100, electrolysis workshop; 200, first heat exchanger; 210, liquid inlet; 220, liquid outlet; 230, steam discharge port; 240, steam connection port; 250, condensate pipe; 300, second heat exchanger; 400, filtered brine tank; 410, filtered brine pump; 500, chlorine scrubbing tower; 510, return pipeline; 600, resin filtration tower; 700, chlorine water collection tank; 710, dechlorinated chlorine water tank; 800, steam transmission pipe; 900, circulation system; 910, first liquid inlet pipe; 911, first control valve; 920, first liquid outlet pipe; 921, second control valve; 922, seventh control valve; 930, second liquid outlet pipe; 931, third control valve; 940, first circulation pipe; 941, fourth control valve; 950, second circulation pipe; 960, second communication pipe; 961, sixth control valve; 970, first communication pipe; 971, fifth control valve. Detailed implementation manners
[0024] In the following text, only some exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the embodiments of the present utility model. Therefore, the accompanying drawings and the description are considered to be exemplary in nature rather than restrictive.
[0025] In the description of the embodiments of the present utility model, it should be understood that the orientation or positional relationships indicated by the terms "length", "vertical", "horizontal", "top", "bottom", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present utility model 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 thus should not be construed as a limitation on the embodiments of the present utility model.
[0026] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present utility model, the meaning of "a plurality" is two or more, unless otherwise specifically defined.
[0027] In the embodiments of the present utility model, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection, or a communication connection; it may be directly connected, or indirectly connected through an intermediate medium, and may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.
[0028] The following disclosure provides many different embodiments or examples for implementing different structures of the embodiments of the present utility model. To simplify the disclosure of the embodiments of the present utility model, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the embodiments of the present utility model. In addition, the embodiments of the present utility model may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplification and clarity and does not itself indicate the relationship between the various embodiments and / or settings discussed.
[0029] To better understand the purpose, structure, and function of the present utility model, the following further describes in detail a device for heating brine using the waste heat of ion-exchange membrane caustic soda with reference to the drawings.
[0030] As Figures 1 - 5As shown in the figure, an embodiment of the present utility model provides a device for heating brine by using the waste heat of ion-exchange membrane caustic soda, including an electrolysis workshop 100 for electrolyzing saturated brine. The electrolysis workshop 100 is connected to a first heat exchanger 200 and a second heat exchanger 300 through pipelines. The first heat exchanger 200 is used for preliminarily heating the filtered brine. After the heating is completed, the filtered brine is transported to the second heat exchanger 300 for reheating. The second heat exchanger 300 is connected to a resin filtration tower 600 installed externally through a pipeline. The upper end of the resin filtration tower 600 is connected to the electrolysis workshop 100 through a pipeline. Among them, pump bodies are arranged in the pipelines to transport the liquid. After being heated to the target temperature, it is transported to the resin filtration tower 600 for filtration, and after the filtration is completed, it is transported to the inside of the electrolysis workshop 100 for electrolysis operation.
[0031] The first heat exchanger 200 and the second heat exchanger 300 are components made of the same structure, and steam inlets 240 and steam outlets 230 for introducing steam to heat the filtered brine are arranged externally. The steam enters from the steam inlet 240 at the upper end and then exits from the steam outlet 230. Because the steam is lighter, it is beneficial for the condensed water at the lower end to drain due to gravity. The first heat exchanger 200 and the second heat exchanger 300 are also provided with a liquid inlet 210 and a liquid outlet 220 for introducing filtered brine externally. The liquid inlet 210 enters from the lower end and exits from the liquid outlet 220 installed at the upper end.
[0032] When it is necessary to heat the filtered brine, the filtered brine enters the first heat exchanger 200 from the liquid inlet 210 for heat exchange operation. The wet chlorine gas from the electrolysis workshop 100 enters through the steam inlet 240 and performs countercurrent heat exchange with the internal filtered brine. After the first heat exchanger 200 completes the heat exchange, it is sent into the second heat exchanger 300 for secondary steam heating, so that the temperature of the filtered brine is increased to 60 °C and enters the resin filtration tower 600 for treatment. After the treatment is completed, it is transported to the electrolysis workshop 100 for electrolysis utilization. The temperature of the wet chlorine gas decreases, and the steam heat of the wet chlorine gas is transferred to the filtered brine, reducing the production cost and at the same time ensuring the comprehensive utilization of the heat of the wet chlorine gas.
[0033] Furthermore, the upper ends of the steam inlets 240 at the upper ends of the first heat exchanger 200 and the second heat exchanger 300 are respectively connected to a steam delivery pipe 800. Control valves are installed in the steam delivery pipe 800 to control the flow rate, and the lower end of the steam delivery pipe 800 is connected to the electrolysis workshop 100. The steam outlets 230 of the first heat exchanger 200 and the second heat exchanger 300 are transported to the chlorine scrubbing tower 500 through a return pipeline 510 for re-scrubbing. The 85 °C wet chlorine gas generated inside the electrolysis workshop 100 performs heat exchange with the filtered brine (50 °C), and the wet chlorine gas steam is transported into the first heat exchanger 200 and the second heat exchanger 300.
[0034] Furthermore, condensate pipes 250 for recovering condensate water are installed at the bottoms of the first heat exchanger 200 and the second heat exchanger 300. The condensate pipes 250 are connected to the chlorine water collection tank 700. The condensed chlorine water is pumped to the dechlorinated chlorine water tank 710 for recycling after controlling the liquid level.
[0035] Furthermore, the first heat exchanger 200 and the second heat exchanger 300 are connected to the filtered brine tank 400 through pipes. The filtered brine tank 400 supplies materials to the pipeline at the liquid inlet 210 through the filtered brine pump 410, for transporting and feeding the filtered brine to be processed.
[0036] A circulation system 900 for controlling the flow of the distributed liquid is also arranged at the positions of the liquid inlet 210 and the liquid outlet 220. The circulation system 900 is connected to the first heat exchanger 200 and the second heat exchanger 300, connected to the filtered brine tank 400 at the front end, and connected to the resin filtration tower 600 at the rear end.
[0037] The circulation system 900 includes a first inlet pipe 910 installed at the upper end of the first heat exchanger 200 and connected to the liquid inlet 210 for supplying liquid, a first outlet pipe 920 connected to the liquid outlet 220, and a second outlet pipe 930 installed at the upper end of the second heat exchanger 300. The other end of the first outlet pipe 920 is installed at the liquid inlet 210 position of the second heat exchanger 300. First control valves 911, 921, and 931 for controlling the flow rate are respectively installed at the upper ends of the first inlet pipe 910, the first outlet pipe 920, and the second outlet pipe 930.
[0038] During the heating process of the filtered brine, after being heated once by the first heat exchanger 200, it is heated twice by the second heat exchanger 300, which is convenient for heating up the filtered brine.
[0039] On the other side of the first inlet pipe 910 and the first outlet pipe 920, a first connecting pipe 970 for connecting the first inlet pipe 910 and the first outlet pipe 920 is arranged. A fifth control valve 971 for controlling the first connecting pipe 970 is arranged at the upper end of the first connecting pipe 970.
[0040] A second connecting pipe 960 is installed at the upper ends of the first outlet pipe 920 and the second outlet pipe 930. The second connecting pipe 960 connects the first outlet pipe 920 and the second outlet pipe 930, and is controlled by a sixth control valve 961 arranged in the pipeline. The second control valve 921 is installed at the front end of the second connecting pipe 960. A seventh control valve 922 is installed at the other side position of the second connecting pipe 960, and the seventh control valve 922 is installed in the pipeline of the first outlet pipe 920.
[0041] When the first heat exchanger 200 needs to be shut down for maintenance, close the first control valve 911 and the second control valve 921, open the fifth control valve 971. Wait for the heated brine to enter one end of the first liquid outlet pipe 920 from the first liquid inlet pipe 910, and then enter the second heat exchanger 300 for heating operation, and be discharged from the second liquid outlet pipe 930 installed at the upper end and enter the resin tower for the filtration section. When the second heat exchanger 300 needs to be shut down for maintenance, close the second control valve 921, the third control valve 931, and the fifth control valve 971, open the sixth control valve 961. Wait for the heated brine to enter from the first liquid inlet pipe 910, pass through the first control valve 911 and enter the first heat exchanger 200, and then be discharged from the first liquid outlet pipe 920 at the upper end, pass through the second connecting pipe 960 and enter the second liquid outlet pipe 930 and then be sent to the resin tower. Closing the third control valve 931 can prevent the brine from flowing back into the second heat exchanger 300. It is convenient to ensure the operation of the device when the two groups of coolers are shut down, realize non-stop production, and improve efficiency.
[0042] Further, a first circulation pipe 940 for circulating and transporting liquid is arranged at the upper connection of the first liquid inlet pipe 910 and the first liquid outlet pipe 920, and a second circulation pipe 950 for circulating and transporting liquid is also arranged at the upper part of the first liquid outlet pipe 920 and the second liquid outlet pipe 930. Fourth control valves 941 for controlling the flow rate in the pipes are installed at the upper ends of the first circulation pipe 940 and the second circulation pipe 950. During the individual use of the first heat exchanger 200 or the second heat exchanger 300, the fourth control valves 941 provided in the middle of the first liquid inlet pipe 910 and the first liquid outlet pipe 920 or the first liquid outlet pipe 920 and the second liquid outlet pipe 930 can be opened to form a path for the first circulation pipe 940 or the second circulation pipe 950. The brine pumped out from the liquid outlet 220 can be led back into the cooler for secondary heating, and after heating to the target temperature, open the second control valve 921 or the third control valve 931 to discharge it, which is convenient to heat the brine to the specified temperature for use and facilitate the processing.
[0043] Among them, when the first heat exchanger 200 and the second heat exchanger 300 are working normally, the fourth control valve 941, the fifth control valve 971, and the sixth control valve 961 are kept in the closed state, and the rest of the valves are in the open state.
[0044] Working principle of a device for heating brine using the waste heat of ion-exchange membrane caustic soda: When it is necessary to heat the filtered brine, the filtered brine enters the first heat exchanger 200 from the liquid inlet 210 for heat exchange operation. The wet chlorine gas from the electrolysis workshop 100 enters through the steam inlet 240 and countercurrently exchanges heat with the filtered brine inside. After the heat exchange in the first heat exchanger 200 is completed, it is sent into the second heat exchanger 300 for secondary steam heating, so that the temperature of the filtered brine is raised to 60 °C and enters the resin filtration tower 600 for treatment. After the treatment, it is transported to the electrolysis workshop 100 for electrolytic utilization. The temperature of the wet chlorine gas decreases, and the heat of the wet chlorine gas steam is transferred to the filtered brine, reducing the production cost and at the same time ensuring the comprehensive utilization of the heat of the wet chlorine gas.
[0045] It can be understood that the present utility model is described through some embodiments. As is known to those skilled in the art, without departing from the spirit and scope of the present utility model, various changes or equivalent replacements can be made to these features and embodiments. Additionally, under the teaching of the present utility model, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the present utility model. Therefore, the present utility model is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application belong to the scope protected by the present utility model.
Claims
1. An apparatus for heating brine using the waste heat of ion-exchange membrane caustic soda, characterized in that, Including: An electrolysis workshop for electrolyzing saturated brine. The electrolysis workshop is connected to a first heat exchanger and a second heat exchanger through pipelines. The second heat exchanger is connected to a resin filtration tower installed externally through a pipeline. The upper end of the resin filtration tower is connected to the electrolysis workshop through a pipeline.
2. The device for heating brine by using the waste heat of ion-exchange membrane caustic soda according to claim 1, characterized in that, The first heat exchanger and the second heat exchanger are components made of the same structure, and both are provided with a steam inlet and a steam outlet externally. The first heat exchanger and the second heat exchanger are also provided with a liquid inlet and a liquid outlet externally.
3. The device for heating brine by using the waste heat of ion-exchange membrane caustic soda according to claim 2, wherein, The steam inlets at the upper ends of the first heat exchanger and the second heat exchanger are respectively connected to a steam delivery pipe, and the lower end of the steam delivery pipe is connected to the electrolysis workshop. The steam outlets of the first heat exchanger and the second heat exchanger are transported to a chlorine scrubbing tower through a return pipeline for re-scrubbing.
4. The device for heating brine by using the waste heat of ion-exchange membrane caustic soda according to claim 3, characterized in that, Condensing pipes are installed at the bottoms of the first heat exchanger and the second heat exchanger, and the condensing pipes are connected to a chlorinated water collection tank.
5. The device for heating brine by using the waste heat of ion-exchange membrane caustic soda according to claim 4, wherein The first heat exchanger and the second heat exchanger are connected to a filtered brine tank through a pipe body, and the filtered brine tank is transported and fed through a pipeline to the inlet position by a filtered brine pump.
6. The device for heating brine by using the waste heat of ion-exchange membrane caustic soda according to claim 5, characterized in that, A circulation system is also arranged at the positions of the liquid inlet and the liquid outlet, and the circulation system is connected to the first heat exchanger and the second heat exchanger.
7. An apparatus for heating brine using the waste heat of ion-exchange membrane caustic soda according to claim 6, characterized in that, The circulation system includes a first liquid inlet pipe installed at the upper end of the first heat exchanger and the liquid inlet, a first liquid outlet pipe connected to the liquid outlet, and a second liquid outlet pipe installed at the upper end of the second heat exchanger. The other end of the first liquid outlet pipe is installed at the liquid inlet position of the second heat exchanger. First control valves, second control valves, and third control valves are respectively installed at the upper ends of the first liquid inlet pipe, the first liquid outlet pipe, and the second liquid outlet pipe.
8. A device for heating brine using the waste heat of ion-exchange membrane caustic soda, as claimed in claim 7, wherein, A first circulation pipe is arranged at the connection position at the upper ends of the first liquid inlet pipe and the first liquid outlet pipe, and a second circulation pipe is also arranged at the upper ends of the first liquid outlet pipe and the second liquid outlet pipe. Fourth control valves are installed at the upper ends of the first circulation pipe and the second circulation pipe.
9. The device for heating brine by using the waste heat of ion-exchange membrane caustic soda according to claim 8, characterized in that, A first communication pipe is arranged on the other side of the first liquid inlet pipe and the first liquid outlet pipe, and a fifth control valve is arranged at the upper end of the first communication pipe.
10. A device for heating brine using the waste heat of ion-exchange membrane caustic soda, characterized in that, A second communication pipe is installed at the upper ends of the first liquid outlet pipe and the second liquid outlet pipe. The second communication pipe connects the first liquid outlet pipe and the second liquid outlet pipe, and is controlled by a sixth control valve arranged in the pipeline. The second control valve is installed at the front end of the second communication pipe, and a seventh control valve is installed at the other side position of the second communication pipe. The seventh control valve is installed in the pipeline of the first liquid outlet pipe.