Wastewater electrolysis method and electrolytic cell based on electrode product enrichment electrolytic cell

Abstract

The embodiment of the present invention discloses a wastewater electrolysis method and an electrolytic cell based on an electrode product enrichment electrolytic cell, the electrolytic cell comprising: a cathode, an anode and a double-layer capacitor electrode. The wastewater electrolysis method comprises: in a first electrolysis stage, the double-layer capacitor electrode is electrically connected to the positive electrode of a DC power supply, the cathode is electrically connected to the negative electrode of the DC power supply, and the anode is not electrically connected to the DC power supply, wherein the electrolysis duration is the duration of the first stage, and the electrolysis voltage is the voltage of the first stage; in a second electrolysis stage, the double-layer capacitor electrode is electrically connected to the negative electrode of the DC power supply, the anode is electrically connected to the positive electrode of the DC power supply, and the cathode is not electrically connected to the DC power supply, wherein the electrolysis duration is the duration of the second stage, and the electrolysis voltage is the voltage of the second stage; wherein the first electrolysis stage and the second electrolysis stage are alternately cycled until the electrolysis operation ends. The present invention can enrich the chemical substances and gases produced at the positive and negative electrodes without an ion exchange membrane.

Description

Technical Field

[0001] The invention relates to the technical field of electrolyzing wastewater in an electrolytic cell, and in particular to a wastewater electrolysis method and an electrolytic cell based on an electrode product enrichment electrolytic cell. Background Art

[0002] Animal husbandry supplies 90% of the world's milk, 80% of its meat, and nearly 50% of its grains, which is vital to food security, but it also emits a large amount of solid waste, waste gas and wastewater. Livestock and poultry breeding wastewater contains high concentrations of nitrogen, pathogens, organic matter, etc., and has a high risk of environmental pollution. Discharging substandard breeding wastewater into the natural environment will cause eutrophication of water bodies, destroy the living environment of aquatic animals in natural water bodies, cause environmental deterioration, and endanger people's life, health and safety. In order to solve the above problems, it is necessary to develop relevant pollution treatment technologies. Livestock and poultry wastewater treatment technologies include: 1. Biological methods such as anaerobic ammonia oxidation (lower energy than traditional nitrification and denitrification, but longer startup time), microalgae treatment (because high organic matter inhibits the growth of microalgae, the wastewater must be diluted), etc.; 2. Physical and chemical methods such as material adsorption (there is a risk of secondary pollution), ammonia stripping (high energy consumption), etc.; 3. Electrochemical methods such as electrodialysis, electroammonia oxidation, electrochemical ammonia stripping, bioelectrochemistry, etc.; electrochemical methods are currently mainly based on ion exchange membranes, but ion exchange membranes increase internal resistance and usage costs. Summary of the invention

[0003] Based on this, it is necessary to propose a wastewater electrolysis method and electrolytic cell based on an electrode product enrichment electrolytic cell to address the above problems.

[0004] Specifically, the present invention includes the following contents:

[0005] According to a first aspect of the present invention, an electrode product enrichment electrolytic cell is provided, comprising: an electrolytic cell body, comprising a cathode region, an anode region and a double-layer capacitor electrode region, wherein the cathode region and the anode region are relatively arranged on the inner sides of both sides of the electrolytic cell body, and the double-layer capacitor electrode region is arranged between the cathode region and the anode region; a cathode and an anode, wherein the cathode is arranged in the cathode region, and the anode is arranged in the anode region, and both the cathode and the anode are electrodes made of conductive materials; a double-layer capacitor electrode, which is a high specific capacitance electrode arranged in the double-layer capacitor electrode region, which is used to separate the cathode region and the anode region, and whose surface has a reaction surface with a high specific surface area for storing electrical energy, and which has a porous structure as a whole.

[0006] Optionally, the material used to make the high specific surface area reaction surface corresponding to the double-layer capacitor electrode is an inert material, wherein the inert material is a conductive material that will not be oxidized and dissolved when used as an anode.

[0007] Optionally, the inert material is any one of a carbon material, a noble metal material and an electrochemically inert electrode material prepared from one or more chemical elements.

[0008] Optionally, the number of the double-layer capacitor electrodes is one or more, the appearance of the double-layer capacitor electrodes is a plane, a curved surface or a folded structure, and the double-layer capacitor electrodes are fixed to the inner bottom surface, the top surface or the middle space of the electrolytic cell body.

[0009] In a second aspect of the present invention, there is provided a method for electrolyzing wastewater based on an electrode product enriching electrolytic cell, wherein electrolysis is performed based on the electrode product enriching electrolytic cell described in any one of the above items, and the method comprises:

[0010] In the first electrolysis stage, the double-layer capacitor electrode is electrically connected to the positive pole of the DC power supply, the cathode is electrically connected to the negative pole of the DC power supply, and the anode is not electrically connected to the DC power supply, wherein the electrolysis duration of the first electrolysis stage is the first stage duration, and the electrolysis voltage of the first electrolysis stage is the first stage voltage; in the second electrolysis stage, the double-layer capacitor electrode is electrically connected to the negative pole of the DC power supply, the anode is electrically connected to the positive pole of the DC power supply, and the cathode is not electrically connected to the DC power supply, wherein the electrolysis duration of the second electrolysis stage is the second stage duration, and the electrolysis voltage of the second electrolysis stage is the second stage voltage; wherein, before the start of electrolysis, the first electrolysis stage and the second electrolysis stage are not in order (i.e., electrolysis can be performed first according to the electrolysis method of the first electrolysis stage, or electrolysis can be performed first according to the electrolysis method of the second electrolysis stage, the same below), and after the start of electrolysis, the first electrolysis stage and the second electrolysis stage are alternately cycled until the end of the electrolysis operation.

[0011] Optionally, the wastewater electrolysis method based on the electrode product enrichment electrolytic cell includes: in a first electrolysis stage, the double-layer capacitor electrode is electrically connected to the positive electrode of the DC power supply, the cathode is electrically connected to the negative electrode of the DC power supply, and the anode is not electrically connected to the DC power supply, wherein the electrolysis duration of the first electrolysis stage is the first stage duration, and the electrolysis voltage of the first electrolysis stage is the first stage voltage; in a second electrolysis stage, the double-layer capacitor electrode and the anode are short-circuited and electrically connected or connected to a load, and the cathode is not electrically connected to the DC power supply, wherein the electrolysis duration of the second electrolysis stage is the second stage duration; wherein, before the start of electrolysis, the first electrolysis stage and the second electrolysis stage are not in order, and after the start of electrolysis, the first electrolysis stage and the second electrolysis stage are alternately cycled until the electrolysis operation is completed.

[0012] Optionally, the wastewater electrolysis method based on the electrode product enrichment electrolytic cell includes: in a first electrolysis stage, the double-layer capacitor electrode is electrically connected to the negative electrode of the DC power supply, the anode is electrically connected to the positive electrode of the DC power supply, and the cathode is not electrically connected to the DC power supply, wherein the electrolysis duration of the first electrolysis stage is the duration of the first stage, and the electrolysis voltage of the first electrolysis stage is the voltage of the first stage; in a second electrolysis stage, the double-layer capacitor electrode and the cathode are short-circuited and electrically connected or connected to a load, the anode is not electrically connected to the DC power supply, and the electrolysis duration of the second electrolysis stage is the duration of the second stage; wherein, before the start of electrolysis, the first electrolysis stage and the second electrolysis stage are not in order, and after the start of electrolysis, the first electrolysis stage and the second electrolysis stage are alternately cycled until the electrolysis operation is completed.

[0013] Optionally, if there are multiple double-layer capacitor electrodes, all of the double-layer capacitor electrodes are electrically connected to the positive pole of the DC power supply in the first electrolysis stage, and all of the double-layer capacitor electrodes are electrically connected to the negative pole of the DC power supply in the second electrolysis stage.

[0014] Optionally, the duration of the first stage is the same as or different from the duration of the second stage.

[0015] Optionally, the first stage voltage and the second stage voltage are the same or different, and the electrolysis voltage is 0.3-16V.

[0016] The beneficial effects of the present invention include but are not limited to:

[0017] During the electrolysis process of the first electrolysis stage and the second electrolysis stage of the present invention, a reduction reaction occurs on the cathode surface of the electrolytic cell, an oxidation reaction occurs on the anode surface of the electrolytic cell, and a double-layer energy storage reaction occurs on the double-layer capacitor electrode, specifically: 1. When the double-layer capacitor electrode is connected to the positive electrode of a DC power supply, anions in the solution will be adsorbed on its surface due to the positive charges accumulated on the surface of the double-layer capacitor electrode; 2. When the double-layer capacitor electrode is connected to the negative electrode of a DC power supply, cations will be adsorbed on the surface due to the negative charges accumulated on the surface of the double-layer capacitor electrode. Because the double-layer capacitor electrode separates the areas where the cathode and anode are located, due to the combined effect of the electric field and the ion polarity, the products of the areas where the cathode and anode are located will not migrate to the other area. Therefore, the present invention can enrich the chemical substances and gases (such as hydrogen, oxygen, ammonia and chlorine, etc.) produced at the positive and negative electrodes, and the products of the positive and negative electrodes will not mix. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] in:

[0020] Figure 1 This is a schematic diagram of the overall structure of an electrode product enrichment electrolytic cell after being electrically connected to a DC power supply according to one embodiment of the present invention;

[0021] Figure 2 An exploded view of the overall structure of an electrode product enrichment electrolytic cell according to one embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the overall structure of an electrode product enrichment electrolytic cell having two double electric layer capacitor electrodes according to one embodiment of the present invention after being electrically connected to a direct current power supply;

[0023] Figure 4 An exploded view of the overall structure of an electrode product enrichment electrolytic cell having two double electric layer capacitor electrodes according to one embodiment of the present invention;

[0024] Figure 5 It is a schematic diagram of the overall structure of a double-layer capacitor having a curved electrode product enrichment electrolytic cell after being electrically connected to a DC power supply according to one embodiment of the present invention;

[0025] Figure 6 An exploded view of the overall structure of an electrode product enrichment electrolytic cell with a curved surface for a double-layer capacitor electrode according to one embodiment of the present invention;

[0026] Figure 7 It is a schematic diagram of the overall structure of an electrode product enrichment electrolytic cell in which the double electric layer capacitor electrode is arranged on the top surface of the electrolytic cell and is electrically connected to a DC power supply according to one embodiment of the present invention;

[0027] Figure 8 An exploded view of an electrode product enrichment electrolytic cell in which the double electric layer capacitor electrode is arranged on the top surface of the electrolytic cell according to one embodiment of the present invention;

[0028] Fig. 9 This is a schematic diagram of an electrolysis process using a first electrolysis mode according to an embodiment of the present invention;

[0029] Fig.10 A schematic diagram of an electrolysis process using a second electrolysis mode according to an embodiment of the present invention;

[0030] Fig.11This is a schematic diagram of an electrolysis process using a third electrolysis mode according to an embodiment of the present invention;

[0031] Fig.12 This is a schematic diagram of electrolysis test results of Example 1 according to one embodiment of the present invention;

[0032] Fig.13 This is a schematic diagram of electrolysis test results of Example 2 according to one embodiment of the present invention;

[0033] Fig.14 This is a schematic diagram of electrolysis test results of Example 3 according to one embodiment of the present invention;

[0034] Fig.15 It is a schematic diagram of the removal effect of ammonia nitrogen on simulated wastewater in the electrolysis test results of Example 4 according to one embodiment of the present invention;

[0035] Fig.16 This is a schematic diagram of the effect of removing ammonia nitrogen from actual livestock and poultry breeding wastewater in the electrolysis test results of Example 4 according to one embodiment of the present invention;

[0036] Fig.17 This is a schematic diagram of ammonia nitrogen removal rate and energy consumption for actual wastewater in the electrolysis test results of Example 4 according to one embodiment of the present invention.

[0037] Among them, the relationship between the marked numbers in the accompanying drawings and the corresponding actual parts is: 1-anode; 2-double-layer capacitor electrode; 3-cathode; 4-fixing screw; 5-fixing nut; 6-positive electrode of DC power supply; 7-relay; 8-negative electrode of DC power supply; 9-anode area electrolytic cell; 10-double-layer capacitor electrode clamp; 11-cathode area electrolytic cell; 12-electrolytic cell body cover; 13-electrolytic cell body. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Please see attached Figure 1-8 , an electrode product enrichment electrolytic cell of the present invention comprises the following parts:

[0040] The electrolytic cell body 13 includes a cathode region, an anode region and a double-layer capacitor electrode region, wherein the cathode region and the anode region are relatively arranged on the inner sides of both sides of the electrolytic cell body 13, and the double-layer capacitor electrode region is arranged between the cathode region and the anode region.

[0041] The cathode 3 and the anode 1 are arranged in the cathode region, and the anode 1 is arranged in the anode region. Both the cathode 3 and the anode 1 are electrodes made of conductive materials.

[0042] The double-layer capacitor electrode 2 is used to separate the cathode region and the anode region, and has a reaction surface with a high specific surface area for storing electrical energy. The whole has a porous structure (not shown in the figure) to allow electrolyte to pass through. When electrolyte is stored in the electrolytic cell body 13, the electrolyte can flow between the cathode 3 and the anode 1 through the porous structure of the double-layer capacitor electrode 2.

[0043] Among them, the cathode 3, the anode 1 and the double-layer capacitor electrode 2 are locked to the electrolytic cell body 13 by screws 4 and nuts 5. The electrolytic cell body 13 includes a cathode area electrolytic cell 11, an anode area electrolytic cell 9 and a double-layer capacitor electrode clamp 10, and an electrolytic cell body cover 12 is provided on the top of the electrolytic cell body 13.

[0044] Among them, the anode 1 is used to electrically connect to the positive pole 6 of the DC power supply, the cathode 3 is used to electrically connect to the negative pole 8 of the DC power supply, and the double-layer capacitor electrode 2 can be selected to be electrically connected to the positive pole 6 of the DC power supply or the negative pole 8 of the DC power supply through the relay 7 according to actual conditions.

[0045] Please refer to the attached Figure 9-11 , in the attached Figure 9-11 The part between the cathode and the anode is a double-layer capacitor electrode, wherein the wastewater electrolysis method based on the electrode product enrichment electrolytic cell of the present invention includes three electrolysis modes:

[0046] The first electrolysis mode is:

[0047] In the first electrolysis stage, the double-layer capacitor electrode is electrically connected to the positive electrode of the DC power supply, the cathode is electrically connected to the negative electrode of the DC power supply, and the anode is not electrically connected to the DC power supply, wherein the electrolysis duration is the duration of the first stage, and the electrolysis voltage is the voltage of the first stage; in the second electrolysis stage, the double-layer capacitor electrode is electrically connected to the negative electrode of the DC power supply, the anode is electrically connected to the positive electrode of the DC power supply, and the cathode is not electrically connected to the DC power supply, wherein the electrolysis duration is the duration of the second stage, and the electrolysis voltage is the voltage of the second stage; wherein, at the beginning of the electrolysis, the first electrolysis stage and the second electrolysis stage are not in order (that is, the electrolysis can be carried out first according to the electrolysis method of the first electrolysis stage, or the electrolysis can be carried out first according to the electrolysis method of the second electrolysis stage, the same below), and after the electrolysis starts, the first electrolysis stage and the second electrolysis stage are alternately cycled until the electrolysis operation is completed.

[0048] The second electrolysis mode is:

[0049] In the first electrolysis stage, the double-layer capacitor electrode is electrically connected to the positive electrode of the DC power supply, the cathode is electrically connected to the negative electrode of the DC power supply, and the anode is not electrically connected to the DC power supply, wherein the electrolysis duration of the first electrolysis stage is the duration of the first stage, and the electrolysis voltage of the first electrolysis stage is the voltage of the first stage; in the second electrolysis stage, the double-layer capacitor electrode and the anode are short-circuited and electrically connected or connected to a load, and the cathode is not electrically connected to the DC power supply, wherein the electrolysis duration of the second electrolysis stage is the duration of the second stage; wherein, at the start of electrolysis, the first electrolysis stage and the second electrolysis stage are not in order, and after the start of electrolysis, the first electrolysis stage and the second electrolysis stage are alternately cycled until the electrolysis operation is completed.

[0050] The third electrolysis mode is:

[0051] In the first electrolysis stage, the double-layer capacitor electrode is electrically connected to the negative electrode of the DC power supply, the anode is electrically connected to the positive electrode of the DC power supply, and the cathode is not electrically connected to the DC power supply, wherein the electrolysis duration of the first electrolysis stage is the duration of the first stage, and the electrolysis voltage of the first electrolysis stage is the voltage of the first stage; in the second electrolysis stage, the double-layer capacitor electrode and the cathode are short-circuited and electrically connected or connected to a load, and the anode is not electrically connected to the DC power supply, wherein the electrolysis duration of the second electrolysis stage is the duration of the second stage; wherein, at the start of electrolysis, the first electrolysis stage and the second electrolysis stage are not in order, and after the start of electrolysis, the first electrolysis stage and the second electrolysis stage are alternately cycled until the electrolysis operation is completed.

[0052] In the electrolytic cell, the cathode undergoes a reduction reaction, that is, the cathode receives electrons and undergoes a reduction reaction, usually reducing the cations in the solution to metals or reduced compounds. For example, when electrolyzing a salt solution, the hydrogen ions on the cathode receive electrons to generate hydrogen. The role of the cathode in the electrolytic cell is to receive electrons and undergo a reduction reaction. In the electrolytic cell, the reaction that occurs at the anode is an oxidation reaction, that is, an element or atomic group is oxidized from a low valence to a high valence.

[0053] Example 1

[0054] The implementation of the embodiment of the present invention includes the following steps:

[0055] (1) Preparation of double-layer capacitor electrodes: Mix activated carbon and acetylene black in a mass ratio of 8:1 and grind to obtain a mixed powder. Then mix polyvinylidene fluoride and N-methylpyrrolidone in a mass ratio of 1:36 and stir at 60°C for at least 2 hours to form a transparent colloidal solution. Mix the above mixed powder and colloidal solution in a ratio of 9:37 and continue to stir rapidly for 1 hour to obtain a slurry. Evenly apply the slurry on the surface of the carbon felt, place it in an oven and dry it at 105°C for 12 hours to obtain a double-layer capacitor electrode.

[0056] (2) Construction of an electrode product enrichment electrolytic cell: In an H-type double-chamber electrolytic cell, a double-layer capacitor electrode is placed in the middle of the electrolytic cell to completely separate the cathode chamber and the anode chamber. The two sides separated by the double-layer capacitor electrode are respectively used as a normal anode by a platinum electrode and as a normal cathode by a nickel foam electrode.

[0057] (3) Electrolysis operation: Prepare 0.5 mol / L sodium sulfate (Na2SO4) solution, and add a small amount of bromothymol blue powder (acid-base indicator) as electrolyte. Power it with a 1.1 V DC power supply and realize the operation as shown in the attached figure through a relay. Figure 7 Power cycles are shown, where each electrolysis phase lasts for 10 s.

[0058] Beneficial effects: as attached Fig.12 As shown in the figure, after 80 minutes, base was produced on the left (acid-base indicator is blue), and acid was produced on the right (acid-base indicator is yellow). After running for 1 hour, it can be observed that the normal cathode area turns blue and the normal anode area turns yellow, where blue represents the production of alkaline substances and yellow represents the production of acidic substances. This indicates that water molecules H2O decompose into H at the anode. + , decomposed into OH at the cathode - , and respectively combine with Na2SO4 to become NaOH and H2SO4 and accumulate near the electrode, that is, the ability to decompose the neutral electrolyte into acidic and alkaline electrolytes is achieved, realizing the production of acid and alkali.

[0059] Example 2

[0060] The implementation of the embodiment of the present invention includes the following steps:

[0061] (1) Preparation of double-layer capacitor electrodes: Prepare a slurry in the same manner as in Example 1, apply the slurry evenly on the surface of the carbon cloth, place it in an oven and dry it at 115° C. for 12 h, and after drying, press it under a pressure of 4 MPa to obtain a double-layer capacitor electrode, with cobalt foam as the normal cathode and platinum sheet as the normal anode.

[0062] (2) Construction of an electrode product enrichment electrolytic cell: The cathode region and the anode region of an H-type double-chamber electrolytic cell are separated by a double-layer capacitor electrode, with the normal cathode in the cathode region and the normal anode in the anode region.

[0063] (3) Electrolysis operation: A mixed solution containing 0.38 mol / L sodium nitrite and 0.25 mol / L neutral phosphate is used as the electrolyte, and a 0.8 V DC power supply is used to power the operation. The operation is realized through a relay (see attached). Figure 7 The power supply was cycled as shown, with each electrolysis stage lasting 10 s.

[0064] Beneficial effects: as attached Fig.13 As shown, the cathode product ammonia nitrogen (yellow) was only detected in the cathode area. After 3 hours, only ammonia nitrogen, a product of nitrite reduction, existed in the cathode area, while only nitrate nitrogen, a product of nitrite oxidation, existed in the anode. The reaction product ammonia nitrogen (yellow column) in the cathode area was only detected in the cathode area, but not in the middle double-layer capacitor electrode area and the anode area, indicating that the electrode product enrichment electrolyzer has the ability to enrich electrode products in a specific area and has application prospects in membraneless electrochemical production (separation and purification).

[0065] Example 3

[0066] The implementation of the embodiment of the present invention includes the following steps:

[0067] (1) Preparation of double-layer capacitor electrodes: The slurry was prepared in the same manner as in Example 1, and the slurry was evenly coated on the surface of the carbon felt, and then dried in an oven at 115° C. for 12 h to obtain double-layer capacitor electrodes.

[0068] (2) Construction of the electrode product enrichment electrolytic cell: The platinum sheet is used as the normal cathode and the iron sheet is used as the normal anode. In an H-type electrolytic cell, the original position of the middle diaphragm is replaced with the prepared double-layer capacitor electrode, and the normal cathode and normal anode are placed on both sides of the double-layer capacitor electrode respectively.

[0069] (3) Electrolysis operation: Use 0.5 mol / L sodium sulfate as the electrolyte and a 1.1 V DC power supply to operate the electrolysis via a relay (see attached). Figure 7 In the first electrolysis stage, platinum is the cathode and the double-layer capacitor electrode is the anode. In the second electrolysis stage, no voltage is applied, and the iron electrode and the double-layer capacitor electrode are short-circuited (or connected to a load). At this time, because the double-layer capacitor electrode carries a charge on its surface, the iron electrode will be oxidized. The first electrolysis stage and the second electrolysis stage are cycled alternately in units of 10s.

[0070] Beneficial effects: as attached Fig.14As shown in the figure, after taking out the anode and cathode, it was observed that the cathode product iron salt (dark brown) was enriched on the left, and the anode product sodium hydroxide (pH 13) was enriched on the right. After 10 hours of reaction, iron hydroxide precipitation was produced in the anode area, and the cathode area was a clear mixed solution of sodium hydroxide and sodium sulfate, and the pH value of the solution was about 13. This shows that the electrode product enrichment electrolyzer has the ability to enrich electrode products without an ion exchange membrane, and has application prospects for membraneless electrochemical production (separation and purification).

[0071] Example 4

[0072] The implementation of the embodiment of the present invention includes the following steps:

[0073] (1) Construction of the electrode product enrichment electrolytic cell: The electrolytic cell body is a quartz glass double-chamber electrolytic cell with a total volume of 75 ml. The double-layer capacitor electrode is placed between the two chambers, the platinum electrode serves as the normal cathode, and the ruthenium-iridium-titanium electrode serves as the normal anode.

[0074] (2) Electrolysis operation: The actual wastewater is: 75ml of wastewater from aquaculture farms, with an ammonia nitrogen content of 650-1000mg / L and a conductivity of 7-2.3mS / cm. The simulated wastewater is: simulated wastewater with an ammonia nitrogen content of 180mg / L and a conductivity of 4.23mS / cm adjusted by adding sodium sulfate. Powered by a 2V DC power supply, it is realized through a relay (see attached Figure 7 In the first electrolysis stage, platinum is the cathode and the double-layer capacitor electrode is the anode. In the second electrolysis stage, ruthenium, iridium and titanium are the anode and the double-layer capacitor electrode is the cathode. The first electrolysis stage and the second electrolysis stage are continuously alternated in units of 10s.

[0075] Beneficial effects: as attached Fig.15 As shown, after 16 hours of simulated wastewater electrolysis, the ammonia nitrogen in the cathode area decreased from 150 mg / L to 2 mg / L; because the hydroxide ions produced by the cathode electrolysis of water are enriched, the same local high pH effect as the ion exchange membrane electrochemical ammonia stripping system is achieved, that is, the alkaline products are enriched at the cathode. The alkaline products react with ammonia nitrogen to produce ammonia gas, achieving the reduction of ammonia nitrogen. After 16 hours of simulated wastewater reaction, the ammonia nitrogen in the cathode area decreased to 2 mg / L, and the pH increased to above 10;

[0076] As attached Fig.16 As shown, after 23 hours of electrolysis of actual wastewater, the ammonia nitrogen in the cathode area decreased by 80%, and the carbon-nitrogen ratio increased from 0.1 to 0.9, which has good biodegradability (suitable for subsequent biological treatment), and the ammonia nitrogen in the anode area decreased by 65%, and the carbon-nitrogen ratio increased, which improved biodegradability. After 23 hours of actual wastewater reaction, the total nitrogen decreased by about 80%, and had a carbon-nitrogen ratio for subsequent biological treatment.

[0077] As attached Fig.17As shown in the figure, after a complete reaction cycle (23h) of the actual wastewater, the electrode product enrichment electrolytic cell only consumes 0.8kW·h of electricity to treat 1 kg of ammonia nitrogen under suitable operating conditions. This shows that the livestock and poultry breeding wastewater treatment device (electrode product enrichment electrolytic cell) made based on this system has good application prospects because of its low power consumption, which allows it to rely on photovoltaic systems for power supply and recover the volatilized ammonia as ammonium salts through existing technologies (such as acid absorption of ammonia).

[0078] The present invention overcomes the shortcomings of the prior art. In view of the problem that the electrochemical method currently mainly uses ion exchange membranes to electrolyze livestock and poultry breeding wastewater, but the ion exchange membranes increase internal resistance and use costs, the livestock and poultry breeding wastewater is electrolyzed by a wastewater electrolysis method based on an electrode product enrichment electrolytic cell. Because the double-layer capacitor electrodes separate the areas where the cathode and the anode are located, due to the combined effect of the electric field and the ion polarity, the products in the areas where the cathode and the anode are located will not migrate to the other area. Therefore, the present invention can enrich the chemical substances and gases (such as hydrogen, oxygen, ammonia and chlorine, etc.) generated at the positive and negative electrodes in the absence of ion exchange membranes, and the positive and negative electrode products will not mix.

[0079] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0080] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. An electrode product enrichment electrolytic cell, characterized in that: include: An electrolytic cell body, comprising a cathode region, an anode region and a double-layer capacitor electrode region, wherein the cathode region and the anode region are relatively arranged on the inner sides of two sides of the electrolytic cell body, and the double-layer capacitor electrode region is arranged between the cathode region and the anode region; A cathode and an anode, wherein the cathode is arranged in the cathode region, and the anode is arranged in the anode region, and both the cathode and the anode are electrodes made of conductive materials; A double-layer capacitor electrode, which is a high specific capacitance electrode provided in the double-layer capacitor electrode region, and is used to separate the cathode region from the anode region, and has a reaction surface with a high specific surface area on its surface for storing electrical energy, and has a porous structure as a whole, allowing electrolyte to pass through; wherein, when electrolyte is stored in the electrolytic cell body, the electrolyte can flow between the cathode and the anode through the porous structure of the double-layer capacitor electrode, and the double-layer capacitor electrode can select to be electrically connected to the positive electrode of a DC power supply or the negative electrode of a DC power supply through a relay according to actual conditions; The material used to make the high specific surface area reaction surface corresponding to the double-layer capacitor electrode is an inert material, wherein the inert material is a conductive material that will not be oxidized and dissolved when used as an anode.

2. The electrode product enrichment electrolytic cell according to claim 1, characterized in that: The inert material is any one of a carbon material, a noble metal material and an electrochemically inert electrode material prepared from one or more chemical elements.

3. The electrode product enrichment electrolytic cell according to claim 1, characterized in that: The number of the double-layer capacitor electrodes is one or more, and the appearance of the double-layer capacitor electrodes is a plane, a curved surface, or a folded structure. The double-layer capacitor electrodes are fixed to the inner bottom surface, the top surface, or the middle space of the electrolytic cell body.

4. A wastewater electrolysis method based on an electrode product enrichment electrolytic cell, characterized in that: Electrolysis is carried out in an electrode product enrichment electrolytic cell according to any one of claims 1 to 3, comprising: In the first electrolysis stage, the double-layer capacitor electrode is electrically connected to the positive electrode of a DC power supply, the cathode is electrically connected to the negative electrode of the DC power supply, and the anode is not electrically connected to the DC power supply, wherein the electrolysis duration of the first electrolysis stage is the first stage duration, and the electrolysis voltage of the first electrolysis stage is the first stage voltage; In the second electrolysis stage, the double-layer capacitor electrode is electrically connected to the negative pole of the DC power supply, the anode is electrically connected to the positive pole of the DC power supply, and the cathode is not electrically connected to the DC power supply, wherein the electrolysis duration of the second electrolysis stage is the second stage duration, and the electrolysis voltage of the second electrolysis stage is the second stage voltage; There is no particular order between the first electrolysis stage and the second electrolysis stage before the start of electrolysis, and after the start of electrolysis, the first electrolysis stage and the second electrolysis stage are alternately cycled until the electrolysis operation is completed.

5. The wastewater electrolysis method based on the electrode product enrichment electrolytic cell according to claim 4, characterized in that: The electrolysis method of the second electrolysis stage is replaced by: short-circuiting the double-layer capacitor electrode and the anode to be electrically connected or connected to a load, and the cathode is not electrically connected to the DC power supply, wherein the electrolysis duration of the second electrolysis stage is the duration of the second stage.

6. The wastewater electrolysis method based on the electrode product enrichment electrolytic cell according to claim 4, characterized in that: The electrolysis method of the first electrolysis stage is replaced by: the double-layer capacitor electrode is electrically connected to the negative electrode of the DC power supply, the anode is electrically connected to the positive electrode of the DC power supply, and the cathode is not electrically connected to the DC power supply, wherein the electrolysis duration of the first electrolysis stage is the duration of the first stage, and the electrolysis voltage of the first electrolysis stage is the voltage of the first stage; the electrolysis method of the second electrolysis stage is replaced by: the double-layer capacitor electrode and the cathode are short-circuited and electrically connected or connected to a load, the anode is not electrically connected to the DC power supply, and the electrolysis duration of the second electrolysis stage is the duration of the second stage.

7. The wastewater electrolysis method based on the electrode product enrichment electrolytic cell according to claim 4, characterized in that: If there are multiple double-layer capacitor electrodes, all of the double-layer capacitor electrodes are electrically connected to the positive pole of the DC power supply in the first electrolysis stage, and all of the double-layer capacitor electrodes are electrically connected to the negative pole of the DC power supply in the second electrolysis stage.

8. The wastewater electrolysis method based on the electrode product enrichment electrolytic cell according to claim 4, characterized in that: The duration of the first stage is the same as or different from the duration of the second stage.

9. The wastewater electrolysis method based on the electrode product enrichment electrolytic cell according to claim 4, characterized in that: The first stage voltage and the second stage voltage are the same or different, and the electrolysis voltage is 0.3-16 V.

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