Tetraalkylammonium hydroxide wastewater treatment device based on adsorption method

Abstract

This utility model discloses a tetraalkylammonium hydroxide wastewater treatment device based on adsorption, relating to the field of wastewater treatment technology. The device includes a central flow channel and a collection tank. The technical solution involves setting a positive electrode and a negative electrode on two opposite sidewalls within the central flow channel, both powered by a power source. Wastewater is introduced into the central flow channel through a first valve, where tetraalkylammonium hydroxide ions and hydroxide ions are adsorbed onto the negative and positive electrodes, respectively. The wastewater with removed tetraalkylammonium hydroxide ions is discharged through a second valve. After the wastewater is discharged, the first valve stops supplying wastewater to the central flow channel and introduces pure water. The positive and negative electrodes are short-circuited or the power source is reversed, releasing the adsorbed tetraalkylammonium hydroxide ions and hydroxide ions back into the pure water, resulting in a high-concentration solution containing tetraalkylammonium hydroxide ions.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, and in particular to a tetraalkylammonium hydroxide wastewater treatment device based on adsorption. Background Technology

[0002] Tetraalkylammonium hydroxide is an indispensable key chemical in the semiconductor and electronics industry. Its application spans multiple stages such as chip manufacturing, packaging, and testing. In particular, it is a core developer in the photolithography process, and its role is irreplaceable.

[0003] In addition to generating high-concentration tetramethylammonium hydroxide wastewater during the development process, tetraalkylammonium hydroxide wastewater is also generated due to water washing. These wastewaters have the following characteristics: (1) pH greater than 10; (2) tetraalkylammonium hydroxide concentration ranging from several hundred ppm to 2.5%; (3) huge volume.

[0004] Tetraalkylammonium hydroxide wastewater treatment is widely recognized in the industry as challenging: Tetraalkylammonium hydroxide has a stable molecular structure, making it difficult to degrade using conventional biological treatment methods. Its strong alkalinity and organic amines inhibit microorganisms in activated sludge, traditional biological treatment methods are inefficient, requiring pretreatment to adjust pH, and the neutralization reaction to produce tetramethylammonium salt, which remains toxic and difficult to biodegrade, necessitating further treatment. Therefore, conventional treatment methods require multi-stage processes including neutralization, oxidation, adsorption, and membrane separation. These multiple treatment processes increase energy consumption and time, and result in high reagent costs. Utility Model Content

[0005] The main objective of this invention is to propose a tetraalkylammonium hydroxide wastewater treatment device based on adsorption, which aims to improve the treatment efficiency of tetraalkylammonium hydroxide wastewater and reduce reagent costs.

[0006] To achieve the above objectives, the present invention proposes a tetraalkylammonium hydroxide wastewater treatment device based on adsorption, comprising:

[0007] A central flow channel, wherein a first valve is connected to the inlet end of the central flow channel and a second valve is connected to the outlet end of the central flow channel;

[0008] A collection tank, which is connected to the central flow channel by a pipeline;

[0009] Positive and negative electrodes are respectively provided on opposite sides of the central flow channel.

[0010] In one embodiment, a content detection device is connected to the outlet end of the central channel.

[0011] In one embodiment, the positive electrode and the negative electrode are both arranged parallel to the fluid flow direction in the central channel, or the positive electrode and the negative electrode are both arranged perpendicular to the fluid flow direction in the central channel.

[0012] In one embodiment, a flow guide mesh is provided inside the central flow channel.

[0013] In one embodiment, the tetraalkylammonium hydroxide wastewater treatment device based on adsorption further includes a first membrane layer and a second membrane layer, both of which are disposed within the central flow channel. The first membrane layer is attached to the positive electrode, and the second membrane layer is attached to the negative electrode.

[0014] In one embodiment, the first membrane layer and the second membrane layer together form a first flow channel, in which wastewater flows.

[0015] In one embodiment, the first film layer and the inner wall of the central flow channel form a second flow channel, and the second film layer and the inner wall of the central flow channel form a third flow channel. A flowable electrode is provided in both the second and third flow channels.

[0016] In this process, the flow electrode in the second flow channel is connected to the negative terminal of the power supply to form a flow negative electrode, and the flow electrode in the third flow channel is connected to the positive terminal of the power supply to form a flow positive electrode.

[0017] In one embodiment, the flow electrode comprises activated carbon and its composites or graphene and its composites.

[0018] The technical solution of this utility model involves setting positive and negative electrodes on two opposite sidewalls within a central flow channel, both powered by a power source. Wastewater is introduced into the central flow channel through a first valve, where tetraalkylammonium hydroxide ions and hydroxide ions are adsorbed onto the negative and positive electrodes, respectively. The wastewater, now free of tetraalkylammonium hydroxide ions, is discharged through a second valve. After the wastewater is discharged, the first valve stops supplying wastewater into the central flow channel and introduces pure water. At this point, the positive and negative electrodes are short-circuited or the power supply is reversed, thereby releasing the adsorbed tetraalkylammonium hydroxide ions and hydroxide ions back into the pure water, resulting in a high-concentration solution containing tetraalkylammonium hydroxide ions, which is then discharged through the second valve. This process is repeated to achieve the separation and concentration of tetraalkylammonium hydroxide wastewater, eliminating the neutralization, oxidation, adsorption, and membrane separation steps required in traditional methods. This significantly improves the treatment efficiency of tetraalkylammonium hydroxide wastewater and reduces the cost of chemical treatment. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0020] Figure 1 A schematic diagram of an embodiment of the tetraalkylammonium hydroxide wastewater treatment device based on adsorption provided by this utility model;

[0021] Figure 2 This is a schematic diagram of another embodiment of the tetraalkylammonium hydroxide wastewater treatment device based on adsorption provided by this utility model.

[0022] Explanation of icon numbers:

[0023] 100. Tetraalkylammonium hydroxide wastewater treatment device based on adsorption method; 10. Central flow channel; 20. Negative electrode; 30. Positive electrode; 40. Second flow channel; 50. First membrane layer; 60. Second membrane layer; 70. Third flow channel.

[0024] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0026] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0027] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0028] Tetraalkylammonium hydroxide is an indispensable key chemical in the semiconductor and electronics industry. Its application spans multiple stages such as chip manufacturing, packaging, and testing. In particular, it is a core developer in the photolithography process, and its role is irreplaceable.

[0029] In addition to producing high-concentration tetramethylammonium hydroxide waste liquid during the development process, tetraalkylammonium hydroxide wastewater is also generated due to water washing. These wastewaters have the following characteristics: (1) pH greater than 10; (2) tetraalkylammonium hydroxide concentration ranging from several hundred ppm to 2.5%; (3) huge volume.

[0030] Tetraalkylammonium hydroxide wastewater treatment is widely recognized in the industry as challenging: Tetraalkylammonium hydroxide has a stable molecular structure, making it difficult to degrade using conventional biological treatment methods. Its strong alkalinity and organic amines inhibit microorganisms in activated sludge, traditional biological treatment methods are inefficient, requiring pretreatment to adjust pH, and the neutralization reaction to produce tetramethylammonium salt, which remains toxic and difficult to biodegrade, necessitating further treatment. Therefore, conventional treatment methods require multi-stage processes including neutralization, oxidation, adsorption, and membrane separation. These multiple treatment processes increase energy consumption and time, and result in high reagent costs.

[0031] This invention proposes a tetraalkylammonium hydroxide wastewater treatment device based on adsorption.

[0032] Please see Figure 1 In one embodiment of this utility model, the tetraalkylammonium hydroxide wastewater treatment device based on adsorption includes:

[0033] A central flow channel 10, wherein a first valve is connected to the inlet end of the central flow channel 10 and a second valve is connected to the outlet end of the central flow channel 10;

[0034] A collection tank 80 is connected to the central flow channel 10 via a pipeline.

[0035] In the central flow channel 10, positive electrode 30 and negative electrode 20 are respectively provided on opposite sides.

[0036] It should be noted that the first valve is a three-way valve, with one inlet for wastewater input and one inlet for pure water input.

[0037] It is understood that the inlet end of the central flow channel 10 is connected to a first pipe and a second pipe. Both the first pipe and the second pipe are connected to a first valve. By controlling the first valve, the input of wastewater or pure water into the central flow channel 10 is controlled.

[0038] It is understood that the second valve connected to the outlet end of the central flow channel 10 is a three-way valve. The two outlets of the three-way valve are respectively connected to the third pipe and the fourth pipe. The third pipe is used to discharge wastewater that has removed most of the tetraalkylammonium hydroxide, and the fourth pipe is used to discharge wastewater containing high concentrations of tetraalkylammonium hydroxide. The efficient separation of tetraalkylammonium hydroxide from the wastewater is achieved through the diversion of the two pipes.

[0039] It should be noted that both the positive electrode 30 and the negative electrode 20 are connected to a power source, which supplies energy to the positive electrode 30 and the negative electrode 20. When wastewater containing tetraalkylammonium hydroxide ions passes through the positive and negative electrodes, hydroxide ions and tetraalkylammonium hydroxide ions are adsorbed by the positive and negative electrodes respectively, thereby significantly reducing the amount of tetraalkylammonium hydroxide ions in the remaining wastewater. This achieves the separation and treatment of wastewater containing a large amount of tetraalkylammonium hydroxide ions. The water with the tetraalkylammonium hydroxide ions removed is discharged through the second pipe.

[0040] Understandably, after the water to which tetraalkylammonium hydroxide ions have been removed is discharged, the first valve is controlled to stop the input of wastewater and to transfer pure water into the central flow channel 10. At this time, the positive and negative electrodes are short-circuited or the power supply is reversed to the positive and negative electrodes. The tetraalkylammonium hydroxide ions and hydroxide ions adsorbed by the positive and negative electrodes are released back into the water in the central pipe 10, thereby increasing the concentration of tetraalkylammonium hydroxide ions in the water in the central pipe 10. At this time, the high-concentration tetraalkylammonium hydroxide wastewater is discharged from the third pipe.

[0041] Meanwhile, the high-concentration tetraalkylammonium hydroxide wastewater is discharged from the third pipe and collected by the collection tank 80. Once a tetraalkylammonium hydroxide solution of a certain concentration is obtained, it is taken out and fresh pure water is added.

[0042] It should be noted that both the wastewater input and the pure water input rely on pumps.

[0043] Furthermore, after the high-concentration tetraalkylammonium hydroxide ion wastewater is discharged, the power supply is restored to the positive and negative electrodes, and the first valve is opened, allowing the wastewater to re-enter the central flow channel 10, thereby restarting ion adsorption and achieving wastewater treatment.

[0044] The technical solution of this utility model involves setting the positive electrode 30 and the negative electrode 20 on two opposite sidewalls within the central flow channel 10, respectively, with both electrodes powered by a power source. Wastewater is introduced into the central flow channel 10 through a first valve, where tetraalkylammonium hydroxide ions and hydroxide ions are adsorbed onto the negative electrode 20 and the positive electrode 30, respectively. The wastewater, now free of tetraalkylammonium hydroxide ions, is discharged through a second valve. After the wastewater is discharged, the first valve stops supplying wastewater into the central flow channel 10 and instead supplies pure water. At this point, the positive electrode 30 and the negative electrode 20 are short-circuited or the power supply is reversed, thereby releasing the adsorbed tetraalkylammonium hydroxide ions and hydroxide ions back into the pure water, resulting in a high-concentration solution containing tetraalkylammonium hydroxide ions, which is then discharged through the second valve. This process is repeated to achieve the separation and concentration of tetraalkylammonium hydroxide wastewater, eliminating the neutralization, oxidation, adsorption, and membrane separation steps required in traditional methods. This significantly improves the treatment efficiency of tetraalkylammonium hydroxide wastewater and reduces the cost of chemical treatment.

[0045] In one embodiment, a content detection device is connected to the outlet end of the central channel 10.

[0046] In order for the second valve to accurately separate high-concentration tetraalkylammonium hydroxide wastewater and the wastewater to be removed from tetraalkylammonium hydroxide, a content detection device is installed at the outlet end of the central flow channel 10.

[0047] It should be noted that the content detection device is used to detect the concentration of tetraalkylammonium hydroxide ions in wastewater.

[0048] Understandably, when the content detection device detects that the concentration of tetraalkylammonium hydroxide ions in the discharged wastewater rises to the first threshold, it controls the first valve to stop the input of wastewater and input pure water. The first pipeline stops inputting wastewater into the central flow channel 10, and at this time, the ions adsorbed on the positive and negative electrodes are released back into the pure water in the central flow channel 10.

[0049] It is understandable that when releasing the ions adsorbed on the positive and negative electrodes, a short circuit occurs between the positive and negative electrodes or the power supply is reversed to power the positive and negative electrodes. When the current between the positive and negative electrodes decreases to the second threshold, the second valve discharges the high-concentration solution in the central flow channel 10 from the fourth pipe. After the adsorbed ions are completely released, the first valve stops the input of pure water and re-inputs wastewater into the central flow channel 10, and the power supply is reversed to power the positive and negative electrodes, thereby restarting the adsorption of ions. The content detection device then detects the concentration of tetraalkylammonium hydroxide ions in the discharged wastewater again.

[0050] It should be noted that the setting of the first threshold avoids excessive adsorption by the positive and negative electrodes, which would prevent efficient adsorption of tetraalkylammonium hydroxide ions in the wastewater, thus avoiding the discharge of tetraalkylammonium hydroxide wastewater and affecting the treatment effect.

[0051] It should be noted that the second threshold is set so that when releasing ions adsorbed by the positive and negative electrodes, the more ions released, the smaller the current between the positive and negative electrodes. When the current reaches the second threshold, it indicates that there are no adsorbed ions or the amount of adsorbed ions on the positive and negative electrodes is small, so that the treatment of wastewater in the next cycle can begin.

[0052] Furthermore, the content detection device can be a sensor.

[0053] In one embodiment, the tetraalkylammonium hydroxide wastewater treatment device based on adsorption further includes a control module, which is used to control the operation of the first valve, the second valve, the power supply, etc.

[0054] In one embodiment, the positive electrode 30 and the negative electrode 20 are both arranged parallel to the fluid flow direction in the central flow channel 10, or the positive electrode 30 and the negative electrode 20 are both arranged perpendicular to the fluid flow direction in the central flow channel 10.

[0055] like Figure 1 As shown, the fluid flow direction in the central flow channel 10 is between the positive electrode 30 and the negative electrode 20.

[0056] It is understandable that, such as Figure 1 The direction indicated by the middle arrow is the direction of fluid flow. When the liquid flows in the central channel 10, tetraalkylammonium hydroxide ions in the wastewater are adsorbed by the negative electrode 20, and hydroxide ions are adsorbed by the positive electrode. Since the positive and negative electrodes are parallel to the direction of fluid flow, the tetraalkylammonium hydroxide ions and hydroxide ions can be fully adsorbed by the positive and negative electrodes during the fluid flow process, thereby improving the adsorption effect.

[0057] In another embodiment, the positive electrode 30 and the negative electrode 20 are both arranged perpendicular to the central flow channel 10, that is, the positive electrode 30 and the negative electrode 20 are mounted on the central flow channel 10.

[0058] In one embodiment, a flow guide mesh is provided inside the central flow channel 10.

[0059] In order to ensure that the wastewater flowing between the positive and negative electrodes can be adsorbed by the positive and negative electrodes, a guide mesh is provided in the central flow channel 10.

[0060] It should be noted that the flow guide mesh is arranged between the positive and negative electrodes.

[0061] It is understandable that, since the guide mesh is set between the positive and negative electrodes, the wastewater flowing along the central channel 10 is disturbed by the guide mesh when passing between the positive and negative electrodes, thus generating turbulence. This increases the residence time of the wastewater between the positive and negative electrodes, thereby facilitating the full and efficient adsorption of tetraalkylammonium hydroxide ions and hydroxide ions by the positive and negative electrodes.

[0062] In one embodiment, the tetraalkylammonium hydroxide wastewater treatment device 100 based on adsorption further includes a first membrane layer 50 and a second membrane layer 60, both of which are disposed within the central flow channel 10. The first membrane layer 50 is attached to the positive electrode 30, and the second membrane layer 60 is attached to the negative electrode 20.

[0063] like Figure 2 As shown, a first film layer 50 is provided in the central flow channel 10 near the positive electrode 30, and a second film layer 60 is provided in the central flow channel 10 near the negative electrode 20.

[0064] Understandably, in order to further improve the adsorption efficiency of the positive and negative electrodes, a first film layer 50 and a second film layer 60 are respectively provided on one side of the positive and negative electrodes.

[0065] In one embodiment, both the first membrane layer 50 and the second membrane layer 60 can be cation and anion exchange membranes.

[0066] In another embodiment, both the first membrane layer 50 and the second membrane layer 60 can be microfiltration membranes, ultrafiltration membranes, or nanofiltration membranes.

[0067] In one embodiment, the first membrane layer 50 and the second membrane layer 60 together form a first flow channel, in which wastewater flows.

[0068] like Figure 2As shown, the first flow channel formed between the first membrane layer 50 and the second membrane layer 60 is used for the flow of wastewater, that is, the wastewater that enters the central flow channel 10 through the first valve flows in the first flow channel.

[0069] Understandably, when the positive and negative electrodes are energized, the wastewater sandwiched between the first membrane layer 50 and the second membrane layer 60 can accelerate the separation of tetraalkylammonium hydroxide ions and hydroxide ions with the assistance of the membrane, that is, accelerate the adsorption of tetraalkylammonium hydroxide ions and hydroxide ions by the positive and negative electrodes, thereby improving the treatment efficiency of wastewater.

[0070] In one embodiment, the first film layer 50 and the inner wall of the central flow channel 10 form a second flow channel 40, and the second film layer 60 and the inner wall of the central flow channel 10 form a third flow channel 70. Both the second flow channel 40 and the third flow channel 70 are provided with flowable electrodes.

[0071] The flow electrode in the second flow channel 40 is connected to the negative terminal of the power supply to form a negative flow electrode, and the flow electrode in the third flow channel 70 is connected to the positive terminal of the power supply to form a positive flow electrode.

[0072] It should be noted that after the positive and negative plates adsorb tetraalkylammonium hydroxide ions and hydroxide ions, the positive and negative plates need to be short-circuited or the power supply needs to be reversed, and the central flow channel needs to be blocked in order to remove the tetraalkylammonium hydroxide ions and hydroxide ions adsorbed on the positive and negative plates. This requires repeated operation of the power supply, the first valve and the second valve, which places great demands on the control of the equipment.

[0073] Therefore, such as Figure 2 As shown, a second flow channel 40 is formed between the first membrane layer 50 and the inner wall of the central flow channel 10, and a third flow channel 70 is formed between the second membrane layer 60 and the inner wall of the central flow channel 10. Circulating flow electrodes are provided in both the second flow channel and the third flow channel 70 to form flow electrodes.

[0074] Furthermore, in order to enable the flow electrode to adsorb tetraalkylammonium hydroxide ions and hydroxide ions within the central flow channel 10, an electrode chamber is provided on one side of the central flow channel 10. The flow electrode passes through the electrode chamber before entering the central flow channel 10. The action of the electrode chamber on the flow electrode enables the flow electrode to complete the adsorption of tetraalkylammonium hydroxide ions and hydroxide ions in the wastewater within the central flow channel 10.

[0075] It is understood that the setting of the flow electrode only requires circulating the flow electrode to achieve sustainable wastewater treatment, which greatly improves wastewater treatment efficiency and reduces the complexity of control.

[0076] In one embodiment, the flow electrode is activated carbon and its composite material or graphene and its composite material.

[0077] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A tetraalkylammonium hydroxide wastewater treatment device based on adsorption, characterized in that, include: A central flow channel, wherein a first valve is connected to the inlet end of the central flow channel and a second valve is connected to the outlet end of the central flow channel; A collection tank, which is connected to the central flow channel by a pipeline; Positive and negative electrodes are respectively provided on opposite sides of the central flow channel.

2. The tetraalkylammonium hydroxide wastewater treatment device based on adsorption method as described in claim 1, characterized in that, The outlet end of the central channel is connected to a content detection device.

3. The tetraalkylammonium hydroxide wastewater treatment device based on adsorption method as described in claim 1, characterized in that, Both the positive electrode and the negative electrode are arranged parallel to the fluid flow direction in the central channel, or both the positive electrode and the negative electrode are arranged perpendicular to the fluid flow direction in the central channel.

4. The tetraalkylammonium hydroxide wastewater treatment device based on adsorption method as described in claim 1, characterized in that, A flow guide mesh is installed inside the central flow channel.

5. The tetraalkylammonium hydroxide wastewater treatment device based on adsorption method as described in any one of claims 1 to 4, characterized in that, The adsorption-based tetraalkylammonium hydroxide wastewater treatment device further includes a first membrane layer and a second membrane layer, both of which are disposed within the central flow channel. The first membrane layer is attached to the positive electrode, and the second membrane layer is attached to the negative electrode.

6. The tetraalkylammonium hydroxide wastewater treatment device based on adsorption method as described in claim 5, characterized in that, The first membrane layer and the second membrane layer together form a first flow channel, in which wastewater flows.

7. The tetraalkylammonium hydroxide wastewater treatment device based on adsorption method as described in claim 5, characterized in that, The first film layer and the inner wall of the central flow channel form a second flow channel, and the second film layer and the inner wall of the central flow channel form a third flow channel. Flowable electrodes are provided in both the second and third flow channels. In this process, the flow electrode in the second flow channel is connected to the negative terminal of the power supply to form a flow negative electrode, and the flow electrode in the third flow channel is connected to the positive terminal of the power supply to form a flow positive electrode.

8. The tetraalkylammonium hydroxide wastewater treatment device based on adsorption method as described in claim 7, characterized in that, The flow electrode comprises activated carbon and its composite materials or graphene and its composite materials.

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