Waste gas absorption device and bipolar membrane electrodialysis equipment

Abstract

The utility model relates to the technical field of bipolar membrane electrodialysis, and discloses a waste gas absorption device and bipolar membrane electrodialysis equipment. According to the waste gas absorption device disclosed by the utility model, the waste gas is subjected to two-stage absorption treatment by arranging the two-stage absorption area, and the Venturi tube and the gas buffer mechanism which are matched with each other are arranged, so that the waste gas entering the absorption tower flows upwards at a lower flow speed and is fully mixed with the absorption liquid flowing downwards, the absorption is more complete, and the purification effect is better; chlorine generated in the electrodialysis process is absorbed through the purification effect of the waste gas absorption device, so that the damage to the bipolar membrane electrodialysis device can be reduced, the environmental damage and pollution are avoided, and meanwhile, the environmental protection property and safety of industrial production are ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of bipolar membrane electrodialysis, and particularly to an exhaust gas absorption device and a bipolar membrane electrodialysis device including the exhaust gas absorption device. Background Art

[0002] Bipolar membrane electrodialysis can dissociate water under the action of a direct current electric field, and hydrogen ions and hydroxide ions can be obtained on both sides of the membrane respectively. Bipolar membrane electrodialysis is widely used in the lithium extraction industry from salt lakes because it can convert salts in aqueous solutions into corresponding acids and bases without introducing new components. It usually uses bipolar membrane electrodialysis to increase the lithium content in brine. However, after electrodialysis is energized, electrode reactions occur on the electrode surface of the electrode solution, resulting in an acidic anode solution and generating oxygen and chlorine. And hypochlorous acid generated after chlorine dissolves in water will oxidize the electrodialysis membrane sheets, seriously affecting the operation of bipolar membrane electrodialysis. Therefore, it is necessary to absorb the chlorine gas generated at the anode to facilitate the normal operation of electrodialysis. Summary of the Utility Model

[0003] The purpose of the utility model is to provide an exhaust gas absorption device and a bipolar membrane electrodialysis device including the exhaust gas absorption device to absorb and treat the exhaust gas generated by bipolar membrane electrodialysis.

[0004] To achieve the above purpose, on the one hand, the utility model provides an exhaust gas absorption device for absorbing the exhaust gas generated by bipolar membrane electrodialysis. The exhaust gas absorption device includes:

[0005] An absorption tower, the interior of which is divided into a primary absorption zone and a secondary absorption zone from bottom to top. A first liquid distributor for evenly distributing the absorption liquid downward is provided at the top of the primary absorption zone, and a second liquid distributor for evenly distributing the absorption liquid downward is provided at the top of the secondary absorption zone. An air inlet is opened on the tower side wall of the absorption tower for defining the primary absorption zone, and an exhaust port is opened on the top wall of the absorption tower;

[0006] An air inlet pipe, which passes through the air inlet and is used to introduce the exhaust gas to be absorbed into the primary absorption zone. The air inlet pipe includes a Venturi tube extending vertically in the primary absorption zone, and the end port of the Venturi tube forms the air outlet port of the air inlet pipe. The Venturi tube is used to discharge the exhaust gas to be absorbed at a relatively low flow rate; and

[0007] A gas buffer mechanism, which is arranged below the air outlet port of the air inlet pipe and has a distance from the air outlet port, and is used to make the exhaust gas to be absorbed discharged from the air outlet port flow upward from all around.

[0008] In some embodiments, the gas buffer mechanism includes a bowl-shaped buffer member with an upward opening and a support member supported below the bowl-shaped buffer member, and the central axis of the bowl-shaped buffer member coincides with the central axis of the air outlet port.

[0009] In some embodiments, the distance is between 15 cm and 25 cm.

[0010] In some embodiments, a Pall ring treatment layer is provided at the boundary between the primary absorption zone and the secondary absorption zone.

[0011] In some embodiments, an activated carbon adsorption layer is provided at the top of the secondary absorption zone, and the activated carbon adsorption layer is located above the second liquid distributor.

[0012] In some embodiments, the waste gas absorption device further includes a water tank for storing the absorption liquid, and the water tank is arranged below the absorption tower and is in fluid communication with the absorption tower at the connection between the two.

[0013] In some embodiments, the waste gas absorption device further includes a centrifugal fan, and the centrifugal fan is communicated with the air inlet port of the air inlet pipe to transport the waste gas to be absorbed to the primary absorption zone through the air inlet pipe.

[0014] In some embodiments, the waste gas absorption device further includes a liquid delivery mechanism for delivering the absorption liquid in the water tank to the first liquid distributor and the second liquid distributor.

[0015] In some embodiments, a liquid addition port is provided at the top of the water tank, a liquid discharge port is provided at the bottom of the water tank, and an overflow port is provided at the side of the water tank.

[0016] In some embodiments, a first observation port is provided on the tower side wall of the absorption tower for defining the primary absorption zone, and the position of the first observation port corresponds to the position of the first liquid distributor.

[0017] In some embodiments, a second observation port is provided on the tower side wall of the absorption tower for defining the secondary absorption zone, and the position of the second observation port corresponds to the position of the second liquid distributor.

[0018] On the other hand, the present utility model provides a bipolar membrane electrodialysis device, which includes a bipolar membrane electrodialysis device and the waste gas absorption device described above, and the waste gas absorption device is used for absorbing and treating the waste gas from the bipolar membrane electrodialysis device.

[0019] In some embodiments, the bipolar membrane electrodialysis device further includes a pole liquid tank for receiving the pole liquid flowing out from the bipolar membrane electrodialysis device. The pole liquid tank has an exhaust gas outlet, and the intake pipe is communicated with the exhaust gas outlet.

[0020] Through the above technical solution, the exhaust gas absorption device of the present utility model performs two-stage absorption treatment on the exhaust gas by setting two-stage absorption zones, and by setting a mutually cooperating Venturi tube and a gas buffer mechanism, the exhaust gas entering the absorption tower flows upward at a relatively low flow rate and is fully mixed with the downward flowing absorption liquid, making the absorption more complete and the purification effect better; the chlorine gas generated during the electrodialysis process is absorbed through the purification of the exhaust gas absorption device, which can reduce the damage to the bipolar membrane electrodialysis device, avoid environmental damage and pollution, and at the same time ensure the environmental protection and safety of industrial production.

[0021] Other features and advantages of the present utility model will be described in detail in the subsequent specific embodiments section. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings constituting a part of the present utility model are used to provide a further understanding of the present utility model. The schematic embodiments and descriptions thereof of the present utility model are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0023] Figure 1 is a schematic structural diagram of an embodiment of the exhaust gas absorption device in the present utility model.

[0024] DESCRIPTION OF THE REFERENCE NUMERALS

[0025] 1 - Absorption tower, 11 - First - stage absorption zone, 111 - First liquid distributor, 112 - First observation port, 12 - Second - stage absorption zone, 121 - Second liquid distributor, 122 - Second observation port, 13 - Intake port, 14 - Exhaust port, 15 - Pall ring treatment layer, 16 - Activated carbon adsorption layer, 2 - Intake pipe, 21 - Horizontal pipe section, 22 - Vertical pipe section, 3 - Gas buffer mechanism, 31 - Bowl - shaped buffer member, 32 - Support member, 4 - Water tank, 41 - Liquid filling port, 42 - Drain port, 43 - Overflow port, 44 - Drain pipe, 45 - Valve, 46 - Connecting pipe, 5 - Centrifugal fan, 6 - Liquid delivery mechanism, 61 - Liquid delivery pump, 62 - Liquid delivery main pipe, 63 - Liquid delivery branch pipe. SPECIFIC EMBODIMENTS

[0026] The following further describes in detail the embodiments of the present utility model with reference to the drawings. The following detailed description and drawings are used to exemplarily illustrate the principle of the present utility model, but cannot be used to limit the scope of the present utility model. The present utility model can be implemented in many different forms, not limited to the specific embodiments disclosed herein, but including all technical solutions falling within the scope of the claims.

[0027] The present utility model provides these embodiments to make the present utility model thorough and complete, and to fully convey the scope of the present utility model to those skilled in the art. It should be noted that: unless otherwise specifically stated, the relative arrangements of components and steps, the compositions of materials, numerical expressions and numerical values set forth in these embodiments should be construed as merely exemplary, rather than as limitations.

[0028] It should be noted that in the description of the present utility model, unless otherwise specified, the meaning of "a plurality of" is greater than or equal to two; the orientation or positional relationships indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", etc. are only for the convenience of describing 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 cannot be construed as a limitation of the present utility model. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0029] In addition, the "first", "second" and similar terms used in the present utility model do not denote any order, quantity or importance, but are only used to distinguish different parts. "Vertical" is not strictly vertical, but within the allowable error range. "Parallel" is not strictly parallel, but within the allowable error range. Terms such as "comprising" or "including" mean that the elements before this term cover the elements listed after this term, and do not exclude the possibility of also covering other elements.

[0030] It should also be noted that in the description of the present utility model, unless otherwise clearly specified and defined, the terms "installed", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances. When it is described that a specific device is located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device.

[0031] All terms used in the present utility model have the same meanings as those understood by those of ordinary skill in the art to which the present utility model pertains, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary, for example, should be construed as having meanings consistent with their meanings in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense, unless specifically defined as such here.

[0032] Known technologies, methods, and equipment for those of ordinary skill in the relevant fields may not be discussed in detail, but where appropriate, the technologies, methods, and equipment shall be regarded as part of the specification.

[0033] On the one hand, the present utility model provides an exhaust gas absorption device for absorbing the exhaust gas generated by bipolar membrane electrodialysis. Refer to Figure 1 , the exhaust gas absorption device includes:

[0034] An absorption tower 1, the interior of the absorption tower 1 is divided into a primary absorption zone 11 and a secondary absorption zone 12 from bottom to top. A first liquid distributor 111 for evenly distributing the absorption liquid downward is provided at the top of the primary absorption zone 11, and a second liquid distributor 121 for evenly distributing the absorption liquid downward is provided at the top of the secondary absorption zone 12. An air inlet 13 is opened on the tower side wall of the absorption tower 1 for defining the primary absorption zone 11, and an exhaust port 14 is opened on the top wall of the absorption tower 1;

[0035] An intake pipe 2, the intake pipe 2 passes through the air inlet 13 and is used to introduce the exhaust gas to be absorbed into the primary absorption zone 11. The intake pipe 2 includes a Venturi tube extending vertically in the primary absorption zone 11, and the end port of the Venturi tube forms the air outlet port of the intake pipe 2. The Venturi tube is used to discharge the exhaust gas to be absorbed at a relatively low flow rate; and

[0036] A gas buffer mechanism 3, the gas buffer mechanism 3 is arranged below the air outlet port of the intake pipe 2 and has a distance from the air outlet port, and is used to make the exhaust gas to be absorbed discharged from the air outlet port flow upward from all around.

[0037] Through the above technical solution, the exhaust gas absorption device of the present utility model performs two-stage absorption treatment on the exhaust gas by setting two absorption zones, and by setting a mutually cooperating Venturi tube and gas buffer mechanism, the exhaust gas entering the absorption tower flows upward at a relatively low flow rate and is fully mixed with the downward-flowing absorption liquid, making the absorption more complete and the purification effect better; by the purification effect of the exhaust gas absorption device, the chlorine generated during the electrodialysis process is absorbed, which can reduce the damage to the bipolar membrane electrodialysis device, avoid environmental damage and pollution, and at the same time ensure the environmental protection and safety of industrial production.

[0038] It should be noted that the above-mentioned first liquid distributor 111 and second liquid distributor 121 can be any suitable existing structures. The improvement of the present utility model does not lie in the specific structures of the first liquid distributor 111 and the second liquid distributor 121, so they will not be described in detail herein.

[0039] In the present utility model, as Figure 1In the illustrated embodiment, the intake pipe 2 may include a horizontal pipe section 21 and a vertical pipe section 22 that are connected to each other. Among them, the horizontal pipe section 21 horizontally penetrates the air inlet 13, and the port of the horizontal pipe section 21 located outside the absorption tower 1 forms the intake port of the intake pipe 2; the vertical pipe section 22 is located within the primary absorption zone 11 and is coaxially arranged with the absorption tower 1. The vertical pipe section 22 forms a Venturi tube, and the Venturi tube sequentially includes a small-diameter part with a constant diameter and a large-diameter part with a gradually expanding diameter from top to bottom. When the waste gas in the intake pipe 2 flows to the large-diameter part, the flow rate can be reduced.

[0040] In the present utility model, the gas buffering mechanism 3 can have any appropriate structure as long as it can block the waste gas discharged from the Venturi tube and at the same time guide the waste gas to flow upward from all around. For example Figure 1 In the illustrated embodiment, the gas buffering mechanism 3 may include a bowl-shaped buffer member 31 with an upward opening and a support member 32 supported below the bowl-shaped buffer member 31. The central axis of the bowl-shaped buffer member 31 coincides with the central axis of the air outlet port. The waste gas entering through the intake pipe 2 at a certain flow rate decelerates through the Venturi tube and then flows downward toward the bowl-shaped buffer member 31, and flows upward from all around the bowl-shaped buffer member 31 under the blockage and guidance of the bowl-shaped buffer member 31.

[0041] Among them, the distance between the gas buffering mechanism 3 and the air outlet port of the intake pipe 2 is preferably between 15 cm and 25 cm. Specifically, in Figure 1 it, the distance between the upper end surface of the bowl-shaped buffer member 31 and the air outlet port of the intake pipe 2 is 15 cm.

[0042] In the present utility model, in order to further improve the absorption and purification effect, as Figure 1 shown, a Pall ring treatment layer 15 can also be provided at the boundary line between the primary absorption zone 11 and the secondary absorption zone 12, and an activated carbon adsorption layer 16 can also be provided at the top of the secondary absorption zone 12. The activated carbon adsorption layer 16 is located above the second liquid distributor 121. Through the above arrangement, the waste gas guided to flow upward by the gas buffering mechanism 3 first fully mixes and absorbs with the absorption liquid evenly distributed downward by the first liquid distributor 111, then is purified by the Pall ring treatment layer 15, and then continues to flow upward to fully mix and absorb with the absorption liquid evenly distributed downward by the second liquid distributor 121, and is further purified by the activated carbon adsorption layer 16 and then discharged from the exhaust port 14. That is to say, the waste gas undergoes four-stage absorption treatment from bottom to top, which can make the absorption and purification of the waste gas more thorough, and the gas finally discharged from the exhaust port 14 can be harmlessly discharged into the air, thus realizing pollution-free emission and being green and environmentally friendly.

[0043] In the present utility model, as Figure 1As shown in the figure, the waste gas absorption device may further include a water tank 4 for storing the absorption liquid. The water tank 4 is arranged below the absorption tower 1 and is in fluid communication with the absorption tower 1 at the connection between the two. It can be understood that the absorption tower 1 is arranged above the water tank 4, and communication ports are respectively arranged at corresponding positions at the bottom of the absorption tower 1 and the top of the water tank 4 to achieve the fluid communication between the absorption tower 1 and the water tank 4. The absorption liquid evenly distributed downward by the first liquid distributor 111 and the second liquid distributor 121 can finally flow into the water tank 4 through the communication port.

[0044] Of course, the waste gas absorption device may further include an infusion mechanism 6. The infusion mechanism 6 is used to transport the absorption liquid in the water tank 4 to the first liquid distributor 111 and the second liquid distributor 121. Specifically, as Figure 1 shown, the infusion mechanism 6 may include an infusion pump 61, an infusion main pipe 62, and infusion branch pipes 63. One end of the infusion main pipe 62 extends into the water tank 4, the infusion pump 61 is arranged on the infusion main pipe 62, one ends of the two infusion branch pipes 63 are respectively connected to the infusion main pipe 62, and the other ends are respectively connected to the first liquid distributor 111 and the second liquid distributor 121. Thus, the waste gas absorption device can realize the circulation of the absorption liquid, that is, the absorption liquid in the water tank 4 is input into the absorption tower 1 through the infusion mechanism 6, the first liquid distributor 111, and the second liquid distributor 121, and the absorption liquid entering the absorption tower 1 finally returns to the water tank 4 after acting on the waste gas.

[0045] Among them, the water tank 4 can have any appropriate structural shape. As Figure 1 shown, a liquid addition port 41 may be arranged at the top of the water tank 4, a liquid discharge port 42 may be arranged at the bottom of the water tank 4, and an overflow port 43 may be arranged at the side of the water tank 4. The liquid addition port 41 can be used to add the absorption liquid into the water tank 4, the liquid discharge port 42 can be used for the absorption liquid in the water tank 4 to be discharged, and the overflow port 43 can be used to control the liquid level in the water tank 4 to prevent the liquid in the water tank from being too full and ensure the reliable circulation of the liquid. A liquid discharge pipe 44 may also be connected to the liquid discharge port 42, and a valve 45 may be arranged on the liquid discharge pipe 44 to control the liquid discharge. The overflow port 43 can be communicated with the liquid discharge pipe 44 through a communication pipe 46.

[0046] In the present utility model, as Figure 1 shown, the waste gas absorption device may further include a centrifugal fan 5. The centrifugal fan 5 is communicated with the air inlet port of the air inlet pipe 2 to transport the waste gas to be absorbed to the primary absorption area 11 through the air inlet pipe 2. A first observation port 112 is arranged on the tower side wall of the absorption tower 1 for defining the primary absorption area 11, and the position of the first observation port 112 corresponds to the position of the first liquid distributor 111. A second observation port 122 is arranged on the tower side wall of the absorption tower 1 for defining the secondary absorption area 12, and the position of the second observation port 122 corresponds to the position of the second liquid distributor 121.

[0047] In the present utility model, the absorption liquid can be an alkaline solution, such as sodium hydroxide, for absorbing chlorine gas in the waste gas. The liquid delivery pump 61 can be an acid and alkali resistant pump to prevent the absorbed liquid being transported from damaging the pump.

[0048] On the other hand, the present utility model provides a bipolar membrane electrodialysis device, which includes a bipolar membrane electrodialysis unit and the above-mentioned waste gas absorption device, and the waste gas absorption device is used for absorbing and treating the waste gas from the bipolar membrane electrodialysis unit.

[0049] Furthermore, the bipolar membrane electrodialysis device may further include an electrode liquid tank for receiving the electrode liquid flowing out from the bipolar membrane electrodialysis unit. The electrode liquid tank has a waste gas outlet, and the intake pipe 2 is communicated with the waste gas outlet. That is to say, the centrifugal fan 5 is used to transport the waste gas in the electrode liquid tank to the intake pipe 2. Among them, the centrifugal fan 5 is preferably a large flow rate fan, for example, the treatment air volume ≥ 200 m 3 / h, so that the waste gas in the electrode liquid tank can be output in time, greatly reducing the residence time of chlorine gas in the electrode liquid tank and minimizing the generation of hypochlorite radicals to the greatest extent.

[0050] So far, the embodiments of the present utility model have been described in detail. In order to avoid obscuring the concept of the present utility model, some details well known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed here based on the above description.

[0051] Although some specific embodiments of the present utility model have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present utility model. Those skilled in the art should understand that the above embodiments can be modified or some technical features can be equivalently replaced without departing from the scope and spirit of the present utility model. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way.

Claims

1. An exhaust gas absorption device for absorbing the exhaust gas generated by bipolar membrane electrodialysis, characterized in that, The waste gas absorption device includes: An absorption tower (1), the interior of which is divided into a primary absorption zone (11) and a secondary absorption zone (12) from bottom to top. A first liquid distributor (111) for evenly distributing the absorption liquid downward is provided at the top of the primary absorption zone (11), and a second liquid distributor (121) for evenly distributing the absorption liquid downward is provided at the top of the secondary absorption zone (12). An air inlet (13) is provided on the tower side wall of the absorption tower (1) for defining the primary absorption zone (11), and an exhaust port (14) is provided on the top wall of the absorption tower (1); An intake pipe (2) which passes through the air inlet (13) and is used for introducing the waste gas to be absorbed into the primary absorption zone (11). The intake pipe (2) includes a Venturi tube located in the primary absorption zone (11) and extending vertically. The end port of the Venturi tube forms the air outlet port of the intake pipe (2), and the Venturi tube is used to discharge the waste gas to be absorbed at a relatively low flow rate; and A gas buffer mechanism (3) which is provided below the air outlet port of the intake pipe (2) and has a spacing from the air outlet port, and is used to make the waste gas to be absorbed discharged from the air outlet port flow upward from all around.

2. The exhaust gas absorption device according to claim 1, characterized in that, The gas buffer mechanism (3) includes a bowl-shaped buffer member (31) with an upward opening and a support member (32) supported below the bowl-shaped buffer member (31). The central axis of the bowl-shaped buffer member (31) coincides with the central axis of the air outlet port.

3. The exhaust gas absorption device according to claim 1, characterized in that, The spacing is between 15 cm and 25 cm.

4. The waste gas absorption device according to claim 1, wherein A Pall ring treatment layer (15) is provided at the boundary between the primary absorption zone (11) and the secondary absorption zone (12); and / or An activated carbon adsorption layer (16) is provided at the top of the secondary absorption zone (12), and the activated carbon adsorption layer (16) is located above the second liquid distributor (121).

5. The exhaust gas absorption device according to claim 1, characterized in that, The waste gas absorption device further includes a water tank (4) for storing the absorption liquid. The water tank (4) is provided below the absorption tower (1) and is in fluid communication with the absorption tower (1) at the connection between the two; and / or The waste gas absorption device further includes a centrifugal fan (5), and the centrifugal fan (5) is connected to the air inlet port of the intake pipe (2) to transport the waste gas to be absorbed into the primary absorption zone (11) through the intake pipe (2).

6. The exhaust gas absorption device according to claim 5, characterized in that, The waste gas absorption device further includes an infusion mechanism (6) which is used to transport the absorption liquid in the water tank (4) to the first liquid distributor (111) and the second liquid distributor (121).

7. The exhaust gas absorption device according to claim 5, characterized in that, A liquid addition port (41) is provided at the top of the water tank (4), a liquid discharge port (42) is provided at the bottom of the water tank (4), and an overflow port (43) is provided at the side of the water tank (4).

8. The waste gas absorption device according to any one of claims 1-7, wherein A first observation port (112) is provided on the tower side wall of the absorption tower (1) for defining the first-stage absorption zone (11), and the position of the first observation port (112) corresponds to the position of the first liquid distributor (111); and / or A second observation port (122) is provided on the tower side wall of the absorption tower (1) for defining the second-stage absorption zone (12), and the position of the second observation port (122) corresponds to the position of the second liquid distributor (121).

9. A bipolar membrane electrodialysis device, characterized in that, It includes a bipolar membrane electrodialysis device and the waste gas absorption device according to any one of claims 1-8, and the waste gas absorption device is used for absorbing and treating the waste gas from the bipolar membrane electrodialysis device.

10. The bipolar membrane electrodialysis device according to claim 9, wherein, The bipolar membrane electrodialysis equipment further includes an electrode liquid tank for receiving the electrode liquid flowing out from the bipolar membrane electrodialysis device. The electrode liquid tank has a waste gas outlet, and the inlet pipe (2) is communicated with the waste gas outlet.

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