Secondary chamber salt acid-alkali treatment system based on electrochemical reaction

Abstract

The invention relates to a secondary chamber salt acid-alkali treatment system based on electrochemical reaction, which comprises a plurality of secondary chamber electrochemical reaction units which are communicated with each other, each secondary chamber electrochemical reaction unit comprises two independent chambers which are separated by an electrolytic diaphragm, the two independent chambers are a cathode reaction chamber and an anode reaction chamber, a cathode is arranged in the cathode reaction chamber, and an anode is arranged in the anode reaction chamber. An anode is arranged in the anode reaction chamber; water inlets are formed in the side walls, close to the bottoms, of the cathode reaction chamber and the anode reaction chamber and used for feeding salt-containing wastewater, and water outlets are formed in the side walls, close to the tops, of the cathode reaction chamber and the anode reaction chamber and used for discharging electrolyzed water. The water outlets of the cathode reaction chambers of the plurality of secondary chamber electrochemical reaction units are communicated with one another and converge to an alkali liquor settling tank, and the water outlets of the anode reaction chambers of the plurality of secondary chamber electrochemical reaction units are communicated with one another and converge to an acid liquor tank. 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] The present application relates to the technical field of electrochemical water treatment and saline wastewater resource treatment, and in particular to a secondary chamber salt acid-base treatment system based on electrochemical reaction. Background Art

[0002] Electrochemical reactions have been widely used in wastewater treatment. According to the principle of electrochemical reactions, 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 the electric field, and electrochemical reactions will occur at the cathode to generate hydroxide ions; anions in saline wastewater, such as chloride ions, sulfate ions, and bicarbonate ions, will migrate to the anode under the action of the electric field, and chlorine or oxygen evolution reactions will occur at the anode to generate chlorine or oxygen. Resource treatment of saline wastewater is a development trend, and the use of electrochemical reactions to treat saline wastewater can convert the various ion components in the saline wastewater into products with utilization value, thereby realizing resource treatment of saline wastewater.

[0003] Currently, most of the water treatment systems on the market that rely on electrochemical reactions can only treat one type of ion in the wastewater alone. If another ion needs to be treated, the wastewater after the first treatment needs to be passed into another water treatment system for secondary treatment. This undoubtedly prolongs the water treatment time and affects the efficiency of water treatment, while also increasing the treatment cost.

[0004] Therefore, there is an urgent need in the art for a water treatment system that can simultaneously treat anions and cations in saline wastewater and improve wastewater resource utilization. Summary of the invention

[0005] In order to realize the resource treatment of saline wastewater, improve the water treatment efficiency of saline wastewater and reduce the water treatment cost.

[0006] The present application provides a two-stage chamber salt acid-base treatment system based on electrochemical reaction, which adopts the following technical solution: A secondary chamber salt acid-base treatment system based on electrochemical reaction comprises a plurality of interconnected secondary chamber electrochemical reaction units, wherein the secondary chamber electrochemical reaction units comprise a cathode reaction chamber, a cathode, an anode reaction chamber, an anode and an electrolytic diaphragm, wherein the cathode reaction chamber and the anode reaction chamber are two independent chambers separated by the electrolytic diaphragm, wherein the cathode is arranged in the cathode reaction chamber, and the anode is arranged in the anode reaction chamber; water inlets are arranged on the side walls near the bottom of the cathode reaction chamber and the anode reaction chamber for the entry of saline wastewater, and water outlets are arranged on the side walls near the top of the cathode reaction chamber and the anode reaction chamber for the discharge of water after electrolysis, the water outlets of the cathode reaction chambers of the plurality of secondary chamber electrochemical reaction units are interconnected and converged to an alkali solution precipitation tank, and the water outlets of the anode reaction chambers of the plurality of secondary chamber electrochemical reaction units are interconnected and converged to an acid solution tank.

[0007] Preferably, it also includes an anode chamber water inlet cache box and a cathode chamber water inlet cache box, the anode chamber water inlets of the multiple secondary chamber electrochemical reaction units are connected through the anode chamber water inlet main pipe, and the anode chamber water inlet main pipe is connected to the anode chamber water inlet cache box; the anode chamber water outlets of the multiple secondary chamber electrochemical reaction units are connected through the anode chamber water outlet main pipe, and the anode chamber water outlet main pipe is connected to the acid liquid tank; the cathode chamber water outlets of the multiple secondary chamber electrochemical reaction units are connected through the cathode chamber water outlet main pipe, and the cathode chamber water outlet main pipe is connected to the alkali solution precipitation tank.

[0008] Furthermore, the top of the acid liquid tank is connected to a chlorine recovery device, and the water outlet of the acid liquid tank is connected to the acid liquid utilization module.

[0009] Furthermore, the bottom of the alkali solution precipitation tank is provided with a bottom discharge port and connected to the filter press equipment, the alkali solution precipitation tank is provided with an upper discharge port and connected to the clear alkali solution tank, and the liquid outlet of the clear alkali solution tank is connected to the alkali solution utilization module.

[0010] Preferably, the cathode and anode of each of the secondary chamber electrochemical reaction units are electrically connected to a digital voltmeter.

[0011] Preferably, the anode terminals and cathode terminals of the plurality of secondary chamber electrochemical reaction units are sequentially connected in series and electrically connected to a high-frequency DC power supply.

[0012] Compared with the prior art, the two-stage chamber salt acid-base treatment system based on electrochemical reaction of the present invention has the following beneficial technical effects: 1. The electrochemical reaction-based two-chamber salt acid-base treatment system of the present invention utilizes electrochemical reaction to treat saline wastewater, and can separate anions and cations in the saline wastewater into alkaline solution and acid solution, and then convert each component into products with utilization value, thereby realizing the resource treatment of saline wastewater.

[0013] 2. The electrochemical reaction-based two-stage chamber salt acid-base treatment system of the present invention can separate cations from a part of saline wastewater while separating anions from another part of saline wastewater, and then exchange the treated water, which greatly improves the water treatment efficiency of saline wastewater. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of a two-stage chamber salt acid-base treatment system based on electrochemical reaction provided by the present invention; Figure 2 It is a schematic diagram of the water inlet and outlet connections of the secondary chamber electrochemical reaction unit provided by the present invention; Figure 3 It is a schematic diagram of the connection between the electrochemical reaction unit of the secondary chamber provided by the present invention and the digital display voltmeter; Figure 4 It is a schematic diagram of the power supply connection of the secondary chamber electrochemical reaction unit provided by the present invention; Figure numerals: 1, anode reaction chamber; 2, cathode reaction chamber; 3, anode reaction chamber water inlet; 4, cathode reaction chamber water inlet; 5, anode reaction chamber water outlet; 6, cathode reaction chamber water outlet; 7, electrolytic diaphragm; 8, anode chamber water inlet main pipe; 9, cathode chamber water inlet main pipe; 10, anode chamber water outlet main pipe; 11, cathode chamber water outlet main pipe; 12, anode chamber water inlet buffer box; 13, cathode chamber water inlet buffer box; 14, acid tank; 15, alkali solution precipitation tank; 16, acid solution utilization module; 17, chlorine recovery device; 18, filter press equipment; 19, alkali solution tank; 20, alkali solution utilization module; 21, anode terminal; 22, cathode terminal; 23, anode terminal board; 24, cathode terminal board; 25, high-frequency DC power supply; 26, digital voltmeter. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical scheme and advantages of the embodiment of the present application clearer, the technical scheme of the embodiment of the present application will be clearly and completely described in conjunction with the drawings of the embodiment of the present application. Obviously, the described embodiment is a part of the embodiment of the present application, not all of the embodiments. Based on the described embodiment of the present application, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of this application.

[0016] Unless otherwise defined, the technical terms or scientific terms used herein shall have the common meanings understood by persons with ordinary skills in the field to which this application belongs. The words "one" or "an" and the like used in the patent application specification and claims of this application do not indicate a quantity limitation, but indicate the existence of at least one.

[0017] The following is combined with Figure 1-4 This application is described in further detail.

[0018] The embodiment of the present application discloses a two-stage chamber salt acid-base treatment system based on electrochemical reaction.

[0019] Reference Figure 1 A secondary chamber salt acid-base treatment system based on electrochemical reaction includes a plurality of interconnected secondary chamber electrochemical reaction units, the secondary chamber electrochemical reaction units include a cathode reaction chamber 2, a cathode, an anode reaction chamber 1, an anode and an electrolytic diaphragm 7, the cathode reaction chamber 2 and the anode reaction chamber 1 are two independent chambers separated by the electrolytic diaphragm 7, the cathode is installed in the cathode reaction chamber 2, the cathode terminal 22 extends out of the cathode reaction chamber 2, the anode is installed in the anode reaction chamber 1, the anode terminal 21 extends out of the anode reaction chamber 1, in the anode reaction chamber 1, an electrochemical anode reaction is realized, in the cathode reaction chamber 2, an electrochemical cathode reaction is realized, in the cathode reaction chamber 2, the electrolytic reaction principle of the cathode and the anode is the prior art, and no further elaboration is made.

[0020] Reference Figure 1 and Figure 2 The cathode reaction chamber 2 and the anode reaction chamber 1 are both integrally formed with water inlets on their side walls near the bottom for entry of saline wastewater, and the cathode reaction chamber 2 and the anode reaction chamber 1 are both integrally formed with water outlets on their side walls near the top for discharge of water after electrolysis, the cathode reaction chamber water outlets 6 of multiple secondary chamber electrochemical reaction units are interconnected and converge into an alkali solution precipitation tank 15, and the anode reaction chamber water outlets 5 of multiple secondary chamber electrochemical reaction units are interconnected and converge into an acid solution tank 14.

[0021] Furthermore, a secondary chamber salt acid-base treatment system based on electrochemical reaction also includes an anode chamber water inlet cache box 12 and a cathode chamber water inlet cache box 13. The anode reaction chamber water inlets 3 of multiple secondary chamber electrochemical reaction units are connected through the anode chamber water inlet main pipe 8, and the anode chamber water inlet main pipe 8 is connected to the anode chamber water inlet cache box 12; the anode reaction chamber water outlets 5 of multiple secondary chamber electrochemical reaction units are connected through the anode chamber water outlet main pipe 10, and the anode chamber water outlet main pipe 10 is connected to the acid liquid tank 14; the cathode reaction chamber water outlets 6 of multiple secondary chamber electrochemical reaction units are connected through the cathode chamber water outlet main pipe 11, and the cathode chamber water outlet main pipe 11 is connected to the alkali liquid precipitation tank 15.

[0022] During water treatment, the raw water first enters the anode chamber water inlet buffer box 12 and the cathode chamber water inlet buffer box 13, and then enters the anode reaction chamber 1 and the cathode reaction chamber 2 respectively through the anode chamber water inlet main pipe 8, the anode reaction chamber water inlet 3 and the cathode chamber water inlet main pipe 9, and the cathode reaction chamber water inlet 4, and electrochemical reactions occur in the anode reaction chamber 1 and the cathode reaction chamber 2, and the electrochemical reaction products are then discharged through the anode reaction chamber water outlet 5, the anode chamber water outlet main pipe 10 and the cathode reaction chamber water outlet 6, and the cathode chamber water outlet main pipe 11 into the acid solution tank 14 and the alkali solution precipitation tank 15 respectively.

[0023] Reference Figure 1 and Figure 2 The top of the acid liquid tank 14 is connected to a chlorine recovery device 17, and the water outlet of the acid liquid tank 14 is respectively connected to the acid liquid utilization module 16 and the anode chamber water inlet cache box 12. The water outlet of the acid liquid tank 14 and the anode chamber water inlet cache box 12 can be controlled by a solenoid valve. The acid liquid tank 14 is connected to the chlorine recovery device 17 on the one hand, and is connected to the acid liquid utilization module 16 on the other hand. The chlorine generated by the electrochemical reaction escapes from the acid liquid, and the chlorine gas is recycled through the chlorine recovery device 17. The acid liquid generated by the electrochemical reaction is recycled through the acid liquid utilization module 16; if the acidity is not enough, the acid liquid in the acid liquid tank 14 returns to the anode chamber water inlet cache box 12, and the acid liquid returned to the anode chamber water inlet cache box 12 enters the anode reaction chamber 1 again, and the acidity is further improved. In this embodiment, the chlorine recovery device 17 can be a device that uses sodium hydroxide solution spray purification to recover chlorine and generate a by-product 10% sodium hypochlorite solution, and the tail gas is discharged in compliance with the standards. Its designed processing capacity is 300kg / day, and the chlorine recovery rate is 99.99%. It can also be other processing and recovery equipment. It is existing technology and will not be described in detail.

[0024] Reference Figure 1 and Figure 2 The bottom of the alkali solution precipitation tank 15 is integrally formed with a bottom discharge port and is connected to a filter press 18. Calcium, magnesium ions and other high-valent metal ions are precipitated in the alkali solution precipitation tank 15 and pressed into mud cakes by the filter press 18 for recycling and storage; the alkali solution precipitation tank 15 is integrally formed with an upper discharge port and is connected to a clear alkali liquid tank 19. The liquid outlet of the clear alkali liquid tank 19 is respectively connected to an alkali solution utilization module 20 and a cathode chamber water inlet buffer tank 13. The supernatant of the alkali solution precipitation tank 15 enters the clear alkali liquid tank 19, and the clear alkali liquid tank 19 is connected to the alkali solution utilization module 20 to realize the resource processing of the alkali solution; if the alkalinity of the alkali solution is not enough, the alkali solution of the clear alkali liquid tank 19 returns to the cathode reaction chamber 2 water inlet buffer tank, and then enters the cathode reaction chamber 2 again, and the alkalinity is further improved. In this embodiment, the filter press 18 is a prior art and will not be described in detail.

[0025] Reference Figure 3A digital voltmeter 26 is electrically connected between the cathode terminal 22 and the anode terminal 21 of each secondary chamber electrochemical reaction unit to monitor the cell voltage of each secondary chamber electrochemical reaction unit. In this embodiment, the use of the digital voltmeter 26 is prior art and will not be described in detail.

[0026] Reference Figure 4 The anode terminals 21 and cathode terminals 22 of multiple secondary chamber electrochemical reaction units are connected in series in sequence and electrically connected to the high-frequency DC power supply 25 through the anode terminal plate 23 and the cathode terminal plate 24, so that the reaction current of all secondary chamber electrochemical reaction units can be adjusted.

[0027] The implementation principle of the two-stage chamber salt acid-base treatment system based on electrochemical reaction of the present invention is as follows: The salt-containing wastewater enters the cathode reaction chamber 2 and the anode reaction chamber 1 respectively. Under the action of the electric field force, the cations migrate to the cathode and generate alkaline solution in the cathode reaction chamber 2, and the anions migrate to the anode and generate acid solution in the anode reaction chamber 1. Calcium, magnesium and other high-valent metal cations are precipitated in the alkaline solution and separated from the water by the filter press 18. The supernatant alkaline solution can be recycled and applied to sewage treatment, desulfurization, pH adjustment, etc. The chlorine generated by the electrochemical reaction escapes from the acid solution 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 solution is neutralized with ammonia water to generate a mixture of ammonium chloride and ammonium sulfate, which is a compound fertilizer. It can also be neutralized with lime to generate high-quality gypsum. It realizes resource recycling and improves water treatment efficiency.

[0028] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A two-stage chamber salt acid-base treatment system based on electrochemical reaction, characterized in that: The invention comprises a plurality of interconnected secondary chamber electrochemical reaction units, wherein the secondary chamber electrochemical reaction units comprise a cathode reaction chamber (2), a cathode, an anode reaction chamber (1), an anode and an electrolytic diaphragm (7), wherein the cathode reaction chamber (2) and the anode reaction chamber (1) are two independent chambers separated by the electrolytic diaphragm (7), wherein the cathode is arranged in the cathode reaction chamber (2), and the anode is arranged in the anode reaction chamber (1); a water inlet is arranged on the side wall near the bottom of the cathode reaction chamber (2) and the anode reaction chamber (1) for the entry of saline wastewater, and a water outlet is arranged on the side wall near the top of the cathode reaction chamber (2) and the anode reaction chamber (1) for the discharge of water after electrolysis, wherein the water outlets of the cathode reaction chambers (2) of the plurality of secondary chamber electrochemical reaction units are interconnected and converge into an alkali solution precipitation tank (15), and the water outlets of the anode reaction chambers (1) of the plurality of secondary chamber electrochemical reaction units are interconnected and converge into an acid solution tank (14); It also comprises an anode chamber water inlet buffer box (12) and a cathode chamber water inlet buffer box (13); the anode chamber water inlets (3) of the plurality of secondary chamber electrochemical reaction units are connected via an anode chamber water inlet main pipe (8), and the anode chamber water inlet main pipe (8) is in communication with the anode chamber water inlet buffer box (12); the anode chamber water outlets (5) of the plurality of secondary chamber electrochemical reaction units are connected via an anode chamber water outlet main pipe (10), and the anode chamber water outlet main pipe (10) is in communication with the acid solution box (14); the cathode chamber water outlets (6) of the plurality of secondary chamber electrochemical reaction units are connected via a cathode chamber water outlet main pipe (11), and the cathode chamber water outlet main pipe (11) is in communication with the alkali solution precipitation box (15).

2. A two-stage chamber salt acid-base treatment system based on electrochemical reaction according to claim 1, characterized in that: The top of the acid liquid tank (14) is connected to a chlorine gas recovery device (17), and the water outlet of the acid liquid tank (14) is connected to an acid liquid utilization module (16).

3. The electrochemical reaction-based two-stage chamber salt acid-base treatment system according to claim 1, characterized in that: The alkali solution settling tank (15) is provided with a bottom discharge port at the bottom thereof and is connected to the filter press equipment (18); the alkali solution settling tank (15) is provided with an upper discharge port and is connected to the clear alkali solution tank (19); and the liquid outlet of the clear alkali solution tank (19) is connected to the alkali solution utilization module (20).

4. The electrochemical reaction-based two-stage chamber salt acid-base treatment system according to claim 1, characterized in that: The cathode and anode of each secondary chamber electrochemical reaction unit are electrically connected to a digital voltmeter (26).

5. The two-stage chamber salt acid-base treatment system based on electrochemical reaction according to claim 1 is characterized in that: The anode terminals (21) and cathode terminals (22) of the plurality of secondary chamber electrochemical reaction units are sequentially connected in series and electrically connected to a high-frequency direct current power source (25).

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