Three-stage chamber salt acid-alkali treatment system based on electrochemical reaction

Abstract

The invention relates to a three-stage chamber salt acid-alkali treatment system based on electrochemical reaction, which comprises a plurality of three-stage chamber electrochemical reaction units which are communicated with one another, and each three-stage chamber electrochemical reaction unit is provided with three independent chambers which are separated by an electrolytic diaphragm, the three independent chambers comprise an anode reaction chamber, a desalting chamber and a cathode reaction chamber which are sequentially arranged, an anode bar is arranged in the anode reaction chamber, and a cathode bar is arranged in the cathode reaction chamber; water inlets are formed in the side walls of the lower parts of the anode reaction chamber, the desalting chamber and the cathode reaction chamber; and water outlets are formed in the side walls of the upper parts of the anode reaction chamber, the desalting chamber and the cathode reaction chamber. The method has the effects of realizing resourceful treatment of the salt-containing wastewater, improving the water treatment efficiency of the salt-containing wastewater and reducing the water treatment cost.

Description

Technical Field

[0001] This application relates to the technical fields of electrochemical water treatment and resource treatment of saline wastewater, and particularly relates to a three-chamber salt, acid, and base treatment system based on an electrochemical reaction. Background Art

[0002] Electrochemical reactions have been widely used in wastewater treatment. Cations in saline wastewater, such as sodium and potassium ions, calcium and magnesium ions, and other high-valent metal cations, will migrate to the cathode under the action of an electric field, and electrochemical reactions occur at the cathode to generate hydroxide ions. Anions in saline wastewater, such as chloride ions, sulfate ions, bicarbonate ions, etc., will migrate to the anode under the action of an electric field, and chlorine evolution or oxygen evolution reactions will occur at the anode, generating chlorine gas or oxygen gas. The resource treatment of saline wastewater is a development trend, and using electrochemical reactions to treat saline wastewater can convert each component in the saline wastewater into valuable products, thereby realizing the resource treatment of saline wastewater. Summary of the Invention

[0003] The purpose of the present invention is to realize the resource utilization of saline wastewater through electrochemical water treatment technology, and a three-chamber salt, acid, and base treatment system based on an electrochemical reaction is proposed.

[0004] In order to realize the resource utilization of saline wastewater, the present invention provides the following technical solutions based on electrochemical reactions: A three-chamber salt, acid, and base treatment system based on an electrochemical reaction includes a plurality of interconnected three-chamber electrochemical reaction units. The three-chamber electrochemical reaction unit has three independent chambers separated by an electrolytic diaphragm. The three independent chambers include an anode reaction chamber, a desalination chamber, and a cathode reaction chamber arranged in sequence. An anode rod is arranged in the anode reaction chamber, and a cathode rod is arranged in the cathode reaction chamber; water inlets are provided on the lower side walls of the anode reaction chamber, the desalination chamber, and the cathode reaction chamber, and water outlets are provided on the upper side walls of the anode reaction chamber, the desalination chamber, and the cathode reaction chamber. The water inlet of the desalination chamber is used for the entry of saline wastewater, and after desalination treatment in the desalination chamber, it is discharged through the water outlet of the desalination chamber. The water outlet of the anode chamber is connected to a strong acid liquid tank, and the water outlet of the cathode chamber is connected to an alkali liquid precipitation tank.

[0005] Preferably, it further includes a weak acid liquid tank and a weak base liquid tank. The anodic chamber water inlets of multiple said three-chamber electro-chemical reaction units are connected through an anodic chamber water inlet main pipe, and the anodic chamber water inlet main pipe is communicated with the weak acid liquid tank. The anodic chamber water outlets of multiple three-chamber electro-chemical reaction units are connected through an anodic chamber water outlet main pipe, and the anodic chamber water outlet main pipe is communicated with the strong acid liquid tank; the cathodic chamber water inlets of multiple three-chamber electro-chemical reaction units are connected through a cathodic chamber water inlet main pipe, and the cathodic chamber water inlet main pipe is connected to the weak base liquid tank. The cathodic chamber water outlets of multiple three-chamber electro-chemical reaction units are connected through a cathodic chamber water outlet main pipe, and the cathodic chamber water outlet main pipe is communicated with the alkali liquid precipitation tank.

[0006] Furthermore, a chlorine recovery device is communicated with the top of the strong acid liquid tank, and the water outlet of the strong acid liquid tank is communicated with an acid liquid utilization module.

[0007] Furthermore, a discharge port is provided at the bottom of the alkali liquid precipitation tank and is communicated with a pressure filtration device through the discharge port. An upper discharge port is provided on the outer wall of the upper part of the alkali liquid precipitation tank, and the upper discharge port is used to communicate with a clear alkali liquid tank for discharging the supernatant in the alkali liquid precipitation tank. The clear alkali liquid tank is communicated with an alkali liquid utilization module.

[0008] Preferably, a digital display voltmeter is electrically connected to each of the cathode rods and anode rods of each said three-chamber electro-chemical reaction unit.

[0009] Preferably, the anode connection terminals of the anode rods and the cathode connection terminals of the cathode rods of multiple said three-chamber electro-chemical reaction units are connected in series in sequence and are electrically connected to a high-frequency DC power supply.

[0010] Compared with the prior art, the three-chamber salt acid-base treatment system based on electro-chemical reaction of the present invention has the following beneficial technical effects: The present invention uses a three-pole chamber electro-chemical reaction device to treat salt-containing wastewater. The cations and anions in the salt-containing wastewater enter the anodic reaction chamber and the cathodic reaction chamber respectively and are converted into alkali liquid and acid liquid. The salt-containing wastewater from which the cations and anions are removed meets the water quality requirements of industrial recycled water and is thus recycled. The acid liquid and the alkali liquid are respectively converted into valuable products through the acid liquid utilization module and the alkali liquid utilization module, thereby realizing the resource treatment of the salt-containing wastewater. Description of the Drawings

[0011] Figure 1 is a schematic structural diagram of a three-chamber salt acid-base treatment system based on electro-chemical reaction provided by the present invention; Figure 2 is a schematic diagram of the water inlet and outlet connection of a three-chamber electro-chemical reaction unit provided by the present invention; Figure 3 is a schematic diagram of the connection between a three-chamber electro-chemical reaction unit and a digital display voltmeter provided by the present invention; Figure 4It is a schematic diagram of the power connection of the three-chamber electrochemical reaction unit provided by the present invention; Reference numerals: 1, anodic reaction chamber; 2, cathodic reaction chamber; 3, desalination chamber; 4, anodic chamber water inlet; 5, cathodic chamber water inlet; 6, anodic chamber water outlet; 7, cathodic chamber water outlet; 8, electrolytic diaphragm cation exchange membrane; 9, electrolytic diaphragm anion exchange membrane; 10, desalination chamber water inlet; 11, desalination chamber water outlet; 12, anodic chamber water inlet main pipe; 13, cathodic chamber water inlet main pipe; 14, anodic chamber water outlet main pipe; 15, cathodic chamber water outlet main pipe; 16, weak acid liquid tank; 17, weak base liquid tank; 18, strong acid liquid tank; 19, alkali liquid precipitation tank; 20, acid liquid utilization module; 21, chlorine recovery device; 22, pressure filtration equipment; 23, clarified alkali liquid tank; 24, alkali liquid utilization module; 25, high-frequency DC power supply; 26, cathode terminal; 27, anode terminal; 28, cathode connection board; 29, anode connection board; 30, digital display voltmeter. Specific embodiments

[0012] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.

[0013] Unless otherwise defined, the technical terms or scientific terms used herein shall have the ordinary meanings understood by those of ordinary skill in the art to which the present application belongs. The words such as "a" or "an" used in the specification and claims of the patent application of the present application do not indicate a limitation of quantity, but mean that there is at least one.

[0014] The following will further describe the present application in detail with reference to the attached Figures 1-4 drawings.

[0015] The embodiments of the present application disclose a three-chamber salt, acid and base treatment system based on electrochemical reaction.

[0016] Refer to Figure 1, A three - chamber salt acid - base treatment system based on electrochemical reaction, including multiple interconnected three - chamber electrochemical reaction units. The three - chamber electrochemical reaction unit has three independent chambers formed by separating with electrolytic diaphragms. The three independent chambers include an anodic reaction chamber 1, a desalination chamber 3, and a cathodic reaction chamber 2 arranged in sequence. The anodic reaction chamber 1 and the desalination chamber 3 are separated by an anodic electrolytic diaphragm 8, and the cathodic reaction chamber 2 and the desalination chamber 3 are separated by a cathodic electrolytic diaphragm 9. An anodic rod is installed in the anodic reaction chamber 1, and the anodic terminal of the anodic rod 27 extends out of the anodic reaction chamber 1. A cathodic rod is installed in the cathodic reaction chamber 2, and the cathodic terminal of the cathodic rod 26 extends out of the cathodic reaction chamber 2. In the anodic reaction chamber 1, an electrochemical anodic reaction occurs to generate acid solution. In the cathodic reaction chamber 2, an electrochemical cathodic reaction occurs to generate alkaline solution. In the desalination chamber 3, desalination of saline wastewater occurs to generate fresh water. In this embodiment, the installation and application of the cathodic rod and the anodic rod are prior arts and will not be elaborated too much.

[0017] Refer to Figure 1 and Figure 2 , On the lower side walls of the anodic reaction chamber 1, the desalination chamber 3, and the cathodic reaction chamber 2, water inlets are integrally formed. On the upper side walls of the anodic reaction chamber 1, the desalination chamber 3, and the cathodic reaction chamber 2, water outlets are integrally formed. The water inlet of the desalination chamber 3 is for the entry of saline wastewater, and after desalination treatment in the desalination chamber 3, it is discharged through the water outlet of the desalination chamber 3. The anodic chamber water outlets 6 of multiple three - chamber electrochemical reaction units are interconnected and converge to a strong acid solution tank 18. The cathodic chamber water outlets 7 of multiple three - chamber electrochemical reaction units are interconnected and converge to an alkaline solution precipitation tank 19.

[0018] Furthermore, a three - chamber salt acid - base treatment system based on electrochemical reaction further includes a weak acid solution tank 16 and a weak base solution tank 17. The anodic chamber water inlets 4 of multiple three - chamber electrochemical reaction units are connected through an anodic chamber water inlet main pipe 12, and the anodic chamber water inlet main pipe 12 is connected to the weak acid solution tank 16. The anodic chamber water outlets 6 of multiple three - chamber electrochemical reaction units are connected through an anodic chamber water outlet main pipe 14, and the anodic chamber water outlet main pipe 14 is connected to the strong acid solution tank 18. The cathodic chamber water inlets 5 of multiple three - chamber electrochemical reaction units are connected through a cathodic chamber water inlet main pipe 13, and the cathodic chamber water inlet main pipe 13 is connected to the weak base solution tank 17. The cathodic chamber water outlets 7 of multiple three - chamber electrochemical reaction units are connected through a cathodic chamber water outlet main pipe 15, and the cathodic chamber water outlet main pipe 15 is connected to the alkaline solution precipitation tank 19.

[0019] Refer to Figure 1, a chlorine gas recovery device 21 is connected to the top of the strong acid liquid tank 18. The water outlet of the strong acid liquid tank 18 is respectively connected to the acid liquid utilization module 20 and the weak acid liquid tank 16. The strong acid liquid tank 18 is connected to the chlorine gas recovery device 21 on one hand and the acid liquid utilization module 20 on the other hand. The chlorine gas generated by the electrochemical reaction escapes from the acid liquid, and the resource treatment of chlorine gas is realized through the chlorine gas recovery device 21. The acid liquid generated electrochemically is subjected to resource treatment through the acid liquid utilization module 20. If the acidity is insufficient, the acid liquid in the strong acid liquid tank 18 returns to the weak acid liquid tank 16 and re-enters the anode reaction chamber 1 again to further increase the acidity. In this embodiment, the chlorine gas recovery device 21 can be a device using sodium hydroxide solution spray purification, recovering chlorine gas and generating a by-product of 10% sodium hypochlorite solution, and the tail gas meets the emission standards. Its designed treatment capacity is 300 kg / day, and the chlorine gas recovery rate is 99.99%. It can also be other treatment and recovery devices, which are prior arts and will not be elaborated too much.

[0020] Refer to Figure 1 , a discharge port is integrally formed at the bottom of the alkali liquid precipitation tank 19 and is connected to a filter press device 22 through the discharge port. The calcium and magnesium ions and other high-valent metal ions aggregated in the wastewater precipitate in the strong alkali precipitation tank and are pressed into mud cakes through the filter press device 22 for recycling and storage. An upper discharge port is integrally formed on the outer wall of the upper part of the alkali liquid precipitation tank 19. The upper discharge port is used to connect to the clear alkali liquid tank 23. The liquid outlet of the clear alkali liquid tank 23 is respectively connected to the alkali liquid utilization module 24 and the weak alkali liquid tank 17. The supernatant of the alkali liquid precipitation tank 19 enters the clear alkali liquid tank 23, and the clear alkali liquid tank 23 is connected to the alkali liquid utilization module 24 to realize the resource treatment of the alkali liquid. If the alkalinity of the alkali liquid is insufficient, the alkali liquid in the clear alkali liquid tank 23 returns to the weak alkali liquid tank 17 and re-enters the cathode reaction chamber 2 again to further increase the alkalinity.

[0021] When performing water treatment, clear water is used as the makeup water for the weak acid liquid and the weak alkali liquid. When the acidity of the acid liquid in the strong acid liquid tank 18 meets the requirements, it is discharged into the acid liquid utilization module 20, and at the same time, clear water is replenished into the weak acid liquid tank 16. Similarly, when the alkalinity of the alkali liquid in the strong alkali precipitation tank meets the requirements, it is discharged into the alkali liquid utilization module 24, and at the same time, clear water is replenished into the weak alkali liquid tank 17.

[0022] Refer to Figure 3 , a digital display voltmeter 30 is electrically connected between the cathode terminal 26 of the cathode rod and the anode terminal 27 of the anode rod of each three-stage chamber electrochemical reaction unit, and the cell voltage of each three-stage chamber electrochemical reaction unit can be monitored. In this embodiment, the use of the digital display voltmeter 30 is a prior art and will not be elaborated too much.

[0023] Refer to Figure 4, the anode terminals 27 of the anode rods and the cathode terminals 26 of the cathode rods of multiple three-stage chamber electrochemical reaction units are connected in series in sequence and electrically connected to the high-frequency DC power supply 25 through the anode connection board 29 and the cathode connection board 28, and the reaction current of all three-stage chamber electrochemical reaction units can be adjusted.

[0024] The implementation principle of a three-stage chamber salt acid-base treatment system based on electrochemical reaction of the present invention is as follows: The salt-containing wastewater enters the desalination chamber 3. Under the action of the electric field force, the cations in the salt-containing wastewater migrate towards the cathode, and alkali liquor is generated in the cathode reaction chamber 2. The anions in the salt-containing wastewater migrate towards the anode, and acid liquor is generated in the anode reaction chamber 1. The salt content of the salt-containing wastewater from which cations and anions are removed decreases and is discharged from the water outlet of the desalination chamber 3. Calcium, magnesium and other high-valence metal cations precipitate in the alkali liquor and are separated from water through the pressure filtration device 22. The supernatant alkali liquor can be recycled and applied to sewage treatment, desulfurization, pH value adjustment, etc. The chlorine gas generated by the electrochemical reaction escapes from the strong acid liquor generated in the anode reaction chamber 1, and is absorbed by sodium hydroxide or ammonia water to generate sodium hypochlorite or ammonium chloride. The remaining acid liquor is neutralized with ammonia water to generate a mixed solution of ammonium chloride and ammonium sulfate, or can also be neutralized with lime to generate high-quality gypsum. While realizing resource recycling, the water treatment efficiency is improved.

[0025] The above are all preferred embodiments of this application, and the protection scope of this application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape and principle of this application shall be covered within the protection scope of this application.

Claims

1. A three-chamber salt acid-base treatment system based on electrochemical reaction, characterized in that, It includes multiple interconnected three-chamber electrochemical reaction units. The three-chamber electrochemical reaction unit has three independent chambers formed by electrolytic diaphragms. The three independent chambers include an anodic reaction chamber (1), a desalination chamber (3), and a cathodic reaction chamber (2) arranged in sequence. An anodic rod is arranged in the anodic reaction chamber (1), and a cathodic rod is arranged in the cathodic reaction chamber (2). Water inlets are provided on the lower side walls of the anodic reaction chamber (1), the desalination chamber (3), and the cathodic reaction chamber (2), and water outlets are provided on the upper side walls of the anodic reaction chamber (1), the desalination chamber (3), and the cathodic reaction chamber (2). The water inlet of the desalination chamber (3) is for the entry of saline wastewater, and after desalination treatment in the desalination chamber (3), it is discharged through the water outlet of the desalination chamber (3). The water outlet of the anodic chamber (6) is connected to a strong acid liquid tank (18), and the water outlet of the cathodic chamber (7) is connected to an alkali liquid precipitation tank (19). It also includes a weak acid liquid tank (16) and a weak base liquid tank (17). The anodic chamber water inlets (4) of multiple three-chamber electrochemical reaction units are connected through an anodic chamber water inlet main pipe (12), and the anodic chamber water inlet main pipe (12) is connected to the weak acid liquid tank (16). The anodic chamber water outlets (6) of multiple three-chamber electrochemical reaction units are connected through an anodic chamber water outlet main pipe (14), and the anodic chamber water outlet main pipe (14) is connected to the strong acid liquid tank (18). The cathodic chamber water inlets (5) of multiple three-chamber electrochemical reaction units are connected through a cathodic chamber water inlet main pipe (13), and the cathodic chamber water inlet main pipe (13) is connected to the weak base liquid tank (17). The cathodic chamber water outlets (7) of multiple three-chamber electrochemical reaction units are connected through a cathodic chamber water outlet main pipe (15), and the cathodic chamber water outlet main pipe (15) is connected to the alkali liquid precipitation tank (19). The top of the strong acid liquid tank (18) is connected to a chlorine recovery device (21), and the water outlet of the strong acid liquid tank (18) is connected to an acid liquid utilization module (20). The bottom of the alkali liquid precipitation tank (19) is provided with a discharge port and is connected to a pressure filtration device (22) through the discharge port. An upper discharge port is provided on the upper outer wall of the alkali liquid precipitation tank (19), and the upper discharge port is used to connect to a clear alkali liquid tank (23) for discharging the supernatant in the alkali liquid precipitation tank (19). The clear alkali liquid tank (23) is connected to an alkali liquid utilization module (24).

2. The three-chamber salt acid-base treatment system based on electrochemical reaction according to claim 1, characterized in that: A digital display voltmeter (30) is electrically connected to each of the cathodic rods and anodic rods of the three-chamber electrochemical reaction unit.

3. The three-chamber salt acid-base treatment system based on electrochemical reaction according to claim 1, characterized in that: The anodic connection terminals (27) of the anodic rods and the cathodic connection terminals (26) of the cathodic rods of multiple three-chamber electrochemical reaction units are connected in series in sequence and electrically connected to a high-frequency DC power supply (25).

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