Ultrasonic assisted compression forced circulation electrolytic cell

Abstract

The application provides an ultrasonic-assisted compression type forced circulation electrolytic cell, which is used for solving the technical problems of the existing electrolytic cell with an ultrasonic field, i.e., suspended bubbles are affected by irregular ultrasonic field and re-attached to the electrode surface, so that only part of the bubbles are discharged from the electrolytic cell and the ultrasonic energy utilization rate is low. The electrolytic cell comprises an electrolytic cell shell, a flexible wall, a positive electrode, a negative electrode and a diaphragm. The electrolytic cell shell and the flexible wall jointly form an electrolytic cell tank. The diaphragm divides the tank into a first tank and a second tank. The positive electrode is located in the first tank, and the negative electrode is located in the second tank. The first tank is provided with a first electrolyte inlet and an oxygen gas outlet, and the second tank is provided with a second electrolyte inlet and a hydrogen gas outlet. Unidirectional valves are arranged on the first electrolyte inlet, the oxygen gas outlet, the second electrolyte inlet and the hydrogen gas outlet. Ultrasonic transducers are arranged at the bottom of the first tank and the second tank.

Description

TECHNICAL FIELD

[0001] The present application relates to an electrolytic cell, in particular to an ultrasonic-assisted compression type forced circulation electrolytic cell. BACKGROUND

[0002] At present, hydrogen energy occupies an important position in the fields of aerospace, electronics and electrical appliances, and human life due to its high efficiency, cleanliness, and renewable advantages, and is one of the most potential energies to solve the future energy crisis. The methods for producing hydrogen mainly include coal gasification method, steam conversion method and water electrolysis method, etc. Among them, the water electrolysis method is the most easily applied method for producing hydrogen on a large scale, and the equipment is simple, the preparation process is pollution-free, and the prepared hydrogen has high purity. However, in the actual electrolysis process, when the gas bubbles are generated on the electrode surface, they will not immediately detach from the electrode surface, thereby forming a bubble layer covering the electrode surface, which will hinder the direct contact between the electrode and the electrolyte, reduce the active area of the electrochemical reaction, and affect the hydrogen production.

[0003] Some scholars have proposed adding an ultrasonic external field to cause cavitation effect by high-frequency vibration of ultrasonic to disturb the electrolyte and accelerate the detachment of bubbles on the electrode surface. For example, Chinese patent CN202120101496.7 introduces ultrasonic into a seawater electrolytic cell to prevent scale deposition through ultrasonic vibration and simplify the seawater filtration process; Chinese patent CN201010500830.2 proposes installing an ultrasonic generator in the middle of the electrolytic cell to emit ultrasonic waves to the cathode plate and the anode plate on both sides, so as to eliminate excess bubbles near the cathode plate and the anode plate of the electrolytic cell, thereby improving the electrolysis efficiency of the electrolytic cell. However, only installing an ultrasonic generator in the electrolytic cell, the ultrasonic external field has no regularity in the force acting on the bubbles, and the suspended bubbles in the electrolyte may reattach to the electrode surface under the action of the ultrasonic external field. Only a part of the bubbles can be discharged from the electrolytic cell when the ultrasonic force acting on the bubbles is consistent with the buoyancy direction, and the ultrasonic energy utilization rate is low. SUMMARY

[0004] The present application aims to solve the technical problems in the prior art that the suspended bubbles in the electrolytic cell with added ultrasonic external field may reattach to the electrode surface under the action of irregular ultrasonic external field, resulting in that only a part of the bubbles can be discharged from the electrolytic cell and the ultrasonic energy utilization rate is poor, and provides an ultrasonic-assisted compression type forced circulation electrolytic cell.

[0005] In order to achieve the above-mentioned purpose, the technical solution provided by the present application is as follows:

[0006] An ultrasonic-assisted compression type forced circulation electrolytic cell, characterized in that it comprises an electrolytic cell shell, a flexible wall, a positive electrode and a negative electrode.

[0007] The electrolytic cell shell and the flexible wall form an electrolytic cell tank.

[0008] The electrolytic cell tank body is internally provided with a diaphragm, the diaphragm is connected with the top and bottom of the electrolytic cell shell respectively, and the electrolytic cell tank body is divided into a first tank body and a second tank body;

[0009] The positive electrode is arranged on the inner wall of the electrolytic cell shell and located in the first tank body, and is used for causing the hydroxyl ion to occur oxidation reaction on the positive electrode, so that the hydroxyl ion loses electrons to generate oxygen; the negative electrode is arranged on the inner wall of the electrolytic cell shell and located in the second tank body, and is used for causing the hydrogen ion to occur reduction reaction on the negative electrode, so that the hydrogen ion obtains electrons to generate hydrogen;

[0010] The electrolytic cell shell is provided with a first electrolyte inlet and an oxygen outlet at positions corresponding to the first tank body, and is provided with a second electrolyte inlet and a hydrogen outlet at positions corresponding to the second tank body; the first electrolyte inlet, the oxygen outlet, the second electrolyte inlet and the hydrogen outlet are all provided with a one-way valve, the internal pressure of the electrolytic cell is changed by mechanically extruding the flexible wall surface, and then the one-way valves at the electrolyte inlets and gas outlets are correspondingly opened or closed, so that forced circulation flow is formed in the electrolytic cell;

[0011] The bottom of the first tank body and the bottom of the second tank body are both provided with an ultrasonic vibrator.

[0012] Further, the first electrolyte inlet and the oxygen outlet are located on the two sides of the positive electrode respectively;

[0013] The second electrolyte inlet and the hydrogen outlet are located on the two sides of the negative electrode respectively, so as to improve the gas disturbance effect.

[0014] Further, the first electrolyte inlet is located at the bottom of the first tank body, and the oxygen outlet is located at the top of the first tank body;

[0015] The second electrolyte inlet is located at the bottom of the second tank body, and the hydrogen outlet is located at the top of the second tank body, so as to further improve the gas disturbance effect.

[0016] Further, the two ultrasonic vibrators are arranged on the outer walls of the bottoms of the first tank body and the second tank body respectively, so as to avoid corrosion of the ultrasonic vibrators by the electrolyte; at the same time, the ultrasonic vibrators located at the bottom of the electrolytic cell can accelerate the bubble removal speed.

[0017] The application also provides an ultrasonic-assisted compression type forced circulation electrolytic cell, which is characterized in that the electrolytic cell comprises an electrolytic cell shell, a flexible wall surface, an ultrasonic vibrator and a membrane electrode;

[0018] The electrolytic cell shell and the flexible wall surface jointly form an electrolytic cell tank body;

[0019] The membrane electrode is located inside the electrolytic tank body, and the membrane electrode is connected with the top and bottom of the electrolytic tank shell at two ends respectively, so as to divide the electrolytic tank body into a first tank body and a second tank body.

[0020] The side surface of the membrane electrode located at the first tank body is a positive electrode, which is used for causing the oxidation reaction of hydroxyl ions on the positive electrode, so that the hydroxyl ions lose electrons to generate oxygen; and the side surface of the membrane electrode located at the second tank body is a negative electrode, which is used for causing the reduction reaction of hydrogen ions on the negative electrode, so that the hydrogen ions obtain electrons to generate hydrogen.

[0021] The electrolytic tank shell is provided with a first electrolyte inlet and an oxygen outlet at positions corresponding to the first tank body, and is provided with a second electrolyte inlet and a hydrogen outlet at positions corresponding to the second tank body; the first electrolyte inlet, the oxygen outlet, the second electrolyte inlet and the hydrogen outlet are all provided with a one-way valve, the internal pressure of the electrolytic tank is changed by mechanically extruding the flexible wall surface, and then the one-way valves at the electrolyte inlets and gas outlets are correspondingly opened or closed, so that a forced circulation flow is formed in the electrolytic tank.

[0022] The first tank body and the second tank body are both provided with an ultrasonic vibrator.

[0023] Further, the first electrolyte inlet is located at the bottom of the first tank body, and the oxygen outlet is located at the top of the first tank body.

[0024] The second electrolyte inlet is located at the bottom of the second tank body, and the hydrogen outlet is located at the top of the second tank body.

[0025] Further, the ultrasonic vibrator is arranged at the bottom of the first tank body and the second tank body, which can accelerate the bubble removal speed.

[0026] The beneficial effects of the present application compared with the prior art are:

[0027] 1. The ultrasonic-assisted compression type forced circulation electrolytic tank provided by the present application increases the flexible wall surface and the inlet and outlet single-phase valve on the basis of the existing ultrasonic-assisted electrolytic tank, on the one hand, through the auxiliary compression-recovery process of the flexible wall surface under the mechanical action, the pressure difference inside and outside the electrolytic tank is changed, the one-way valves are arranged at the inlets and outlets of the electrolytic tank to realize the forced circulation flow in the electrolytic tank, so that the bubbles are forced to separate from the electrode surface, enter the electrolyte and then be discharged from the electrolytic tank, and the re-attachment of part of the bubbles after separating from the electrode is avoided; on the other hand, the cavitation effect in the electrolyte is generated by the high-frequency vibration of the ultrasonic vibrator, which cooperates with the electrode surface to flush and accelerate the bubble separation, and avoids the formation of gas film on the electrode surface.

[0028] 2. The ultrasonic-assisted compression type forced circulation electrolytic cell provided by the application, in the flexible wall compression process, the one-way valves of the oxygen outlet and the hydrogen outlet are opened, and the one-way valves of the first electrolyte inlet and the second electrolyte inlet are closed, so that the generated oxygen and hydrogen are discharged; in the flexible wall recovery process, the pressure inside the electrolytic cell is relatively low, the one-way valves of the first electrolyte inlet and the second electrolyte inlet are opened, and the one-way valves of the oxygen outlet and the hydrogen outlet are closed, so that the electrolyte inside the electrolytic cell is supplemented. Through the continuous auxiliary compression and recovery of the flexible wall, the bubbles are accelerated to separate from the electrode surface under the action of the force, and the circulation of the electrolyte can be realized through the compression-recovery process of the flexible wall without additional pump liquid, so that the power consumption is reduced.

[0029] 3. The ultrasonic-assisted compression type forced circulation electrolytic cell provided by the application, the ultrasonic vibrator is located on the outer wall of the bottom of the electrolytic cell, since the bubbles mainly separate from the electrode surface under the upward buoyancy, the rotation direction of the liquid generated by the ultrasonic vibrator located at the bottom is the same as the direction of the buoyancy, so that the bubble separation speed is accelerated; meanwhile, the ultrasonic vibrator is arranged on the outer wall of the electrolytic cell shell, so that the corrosion of the electrolyte to the ultrasonic vibrator is avoided, and the service life of the ultrasonic vibrator is improved.

[0030] 4. The ultrasonic-assisted compression type forced circulation electrolytic cell provided by the application, the first electrolyte inlet and the oxygen outlet are located on the two sides of the positive electrode respectively, and the second electrolyte inlet and the hydrogen outlet are located on the two sides of the negative electrode respectively, compared with the same side model in which the first electrolyte inlet and the second electrolyte inlet are located on the same side, the average turbulent energy in the electrolytic cell of the different side model can be increased by 60%, so that the bubble removal effect is greatly improved, and the electrolysis performance of the electrolytic cell is improved.

[0031] 5. The ultrasonic-assisted compression type forced circulation electrolytic cell provided by the application, the first electrolyte inlet is located at the bottom of the first tank body, the oxygen outlet is located at the top of the first tank body, the second electrolyte inlet is located at the bottom of the second tank body, and the hydrogen outlet is located at the top of the second tank body, compared with the case that the first electrolyte inlet and the second electrolyte inlet are located at other positions of the first tank body and the second tank body respectively, the bubble removal effect is better. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 It is a structure schematic view of the ultrasonic-assisted compression type forced circulation electrolytic cell provided by the application in the compression state, wherein the dashed arrow represents the electrolyte flow direction, and the solid arrow represents the force direction of the flexible wall;

[0033] Figure 2 It is a bubble distribution schematic view of the electrode surface in the existing electrolytic cell with an added ultrasonic field;

[0034] Figure 3Figure 1 is a schematic diagram of a bottom ultrasonic model and a side ultrasonic model of the present application, wherein (a) is a model of an ultrasonic vibrator located at the bottom of a first tank, i.e. a bottom ultrasonic model, and (b) is a model of an ultrasonic vibrator located at the side of a first tank, i.e. a side ultrasonic model;

[0035] Figure 4 Figure 2 is a graph of the gas volume fraction on the surface of an electrode over time for the bottom ultrasonic model of the present application, the side ultrasonic model of the present application, and a non-ultrasonic model;

[0036] Figure 5 Figure 3 is a schematic diagram of a tank model with a flexible wall of the present application and a tank model with a rigid wall of the prior art, wherein (a) is a tank model with a rigid wall of the prior art, and (b) is a tank model with a flexible wall of the present application;

[0037] Figure 6 Figure 4 is a graph of the gas volume fraction on the surface of an electrode over time for the flexible wall tank model of the present application and the rigid wall tank model of the prior art;

[0038] Figure 7 Figure 5 is a schematic diagram of a structure of a different side model of the present application and a same side model of the present application, wherein (a) is a model in which a first electrolyte inlet and an oxygen outlet are located on opposite sides of a positive electrode, i.e. a different side model, and (b) is a model in which a first electrolyte inlet and an oxygen outlet are located on the same side of a positive electrode, i.e. a same side model;

[0039] Figure 8 Figure 6 is a schematic diagram of an internal flow field of the different side model of the present application and the same side model of the present application, wherein (a) is an internal flow field diagram of the different side model, and (b) is an internal flow field diagram of the same side model;

[0040] Figure 9 Figure 7 is a comparison curve of turbulent kinetic energy in an electrolytic tank at different inlet flow rates for the different side model of the present application and the same side model of the present application;

[0041] Figure 10 Figure 8 is a schematic diagram of the first electrolyte inlet located at different positions of an electrolytic tank for the different side model of the present application, wherein (a) is a model in which the first electrolyte inlet is located at the top of the electrolytic tank, (b) is a model in which the first electrolyte inlet is located at the side of the electrolytic tank, and (c) is a model in which the first electrolyte inlet is located at the bottom of the electrolytic tank;

[0042] Figure 11 Figure 9 is a comparison curve of turbulent kinetic energy in an electrolytic tank at different inlet flow rates for the different side model of the present application when the first electrolyte inlet is located at different positions of the electrolytic tank at different inlet flow rates;

[0043] Figure 12 Figure 2 is a structural schematic diagram of a second embodiment of the ultrasonic-assisted compression type forced circulation electrolytic cell of the present application, in which the dotted arrows represent the electrolyte flow direction and the solid arrows represent the flexible wall force direction.

[0044] Reference signs:

[0045] 1 - electrolytic cell housing; 2 - flexible wall; 3 - positive electrode; 4 - negative electrode; 5 - first tank, 51 - first electrolyte inlet, 52 - oxygen outlet; 6 - second tank, 61 - second electrolyte inlet, 62 - hydrogen outlet; 7 - ultrasonic vibrator; 8 - diaphragm; 9 - membrane electrode. DETAILED DESCRIPTION

[0046] In order to make the advantages and characteristics of the present application clearer, the present application will be further described in detail below in combination with the drawings and specific embodiments.

[0047] Embodiment one

[0048] An ultrasonic-assisted compression type forced circulation electrolytic cell is a kind of alkaline electrolytic cell, such as Figure 1As shown, it comprises an electrolytic cell shell 1, a flexible wall 2, a positive electrode 3 and a negative electrode 4. The electrolytic cell shell 1 and the flexible wall 2 form an electrolytic cell tank, by mechanical extrusion of the flexible wall 2, the pressure difference inside the electrolytic cell is changed, the electrolyte is disturbed, and the bubble is accelerated to separate from the electrode surface; in this embodiment, the flexible wall 2 is mechanically extruded by a reciprocating pump. Because oxygen and hydrogen are generated synchronously on the surface of the electrode, in order to obtain pure oxygen and hydrogen, a diaphragm 8 is arranged inside the electrolytic cell tank in this embodiment, the two ends of the diaphragm 8 are respectively connected with the top and bottom of the electrolytic cell shell 1, and the electrolytic cell tank is divided into a first tank 5 and a second tank 6; the positive electrode 3 is arranged on the inner wall of the electrolytic cell shell 1 and located in the first tank 5, for making the hydroxyl ion undergo oxidation reaction on the positive electrode 3, the hydroxyl ion loses electrons to generate oxygen; the negative electrode 4 is arranged on the inner wall of the electrolytic cell shell 1 and located in the second tank 6, for making the hydrogen ion undergo reduction reaction on the negative electrode 4, the hydrogen ion gets electrons to generate hydrogen. The electrolytic cell shell 1 is provided with a first electrolyte inlet 51 and an oxygen outlet 52 corresponding to the position of the first tank 5, and is provided with a second electrolyte inlet 61 and a hydrogen outlet 62 corresponding to the position of the second tank 6. The first electrolyte inlet 51, the oxygen outlet 52, the second electrolyte inlet 61 and the hydrogen outlet 62 are all provided with a one-way valve, when the flexible wall 2 is extruded, a forced circulation flow is formed in the electrolytic cell through the one-way valves on the first electrolyte inlet 51, the oxygen outlet 52, the second electrolyte inlet 61 and the hydrogen outlet 62. Preferably, in order to achieve better gas disturbance effect, the first electrolyte inlet 51 and the oxygen outlet 52 are respectively located on the two sides of the positive electrode 3 in this embodiment, and the first electrolyte inlet 51 is located at the bottom of the first tank 5, and the oxygen outlet 52 is located at the top of the first tank 5; the second electrolyte inlet 61 and the hydrogen outlet 62 are respectively located on the two sides of the negative electrode 4, and the second electrolyte inlet 61 is located at the bottom of the second tank 6, and the hydrogen outlet 62 is located at the top of the second tank 6. The bottom of the first tank 5 and the second tank 6 is provided with an ultrasonic vibrator 7, for better gas disturbance effect by the vibration of the ultrasonic vibrator, but because water is a weak electrolyte, the degree of ionization is very low, and the conductivity is poor, generally some easily ionized substances are added in pure water, such as sodium hydroxide, so that the pH value of the electrolyte changes, therefore, the ultrasonic vibrator 7 is preferably arranged on the outer wall of the bottom of the first tank 5 and the second tank 6 in this embodiment, which can prevent the ultrasonic vibrator 7 from being corroded by sodium hydroxide and other substances.

[0049] It can be understood that the electrolytic cell shell 1 in the present application is used to provide support for the flexible wall 2, the positive electrode 3, the negative electrode 4 and the ultrasonic vibrator 7, wherein the relative positions of the flexible wall 2, the positive electrode 3, the negative electrode 4 and the ultrasonic vibrator 7 have no special requirements and are not limited to the specific positions in this embodiment.

[0050] In order to better understand the advantages of the flexible wall 2 and the setting of the inlet and outlet positions of the electrolytic cell in the ultrasonic-assisted compression type forced circulation electrolytic cell, the first tank body 5 is taken as an example, and further description is made through specific experimental comparison.

[0051] I. Comparison between the bottom ultrasonic model and the side ultrasonic model

[0052] As shown in Figure 2 , it is a schematic diagram of bubble diversion on the electrode surface in the existing electrolytic cell only with an added ultrasonic field. In the electrolytic cell with only an ultrasonic field, a part of the bubbles are trapped in the electrolytic cell due to irregular disturbance of the electrolyte during the process of detaching from the electrode surface, and behaviors such as coalescence and fragmentation occur, as shown by a bubble group; a part of the bubbles reattach to the electrode surface, as shown by a bubble group; only a small amount of bubbles are discharged from the electrolytic cell by relying on their own buoyancy, as shown by a bubble group.

[0053] A structure model as shown in Figure 3 is constructed, wherein Figure 3 (a) in the structure model is a model in which the ultrasonic vibrator 7 is located at the bottom of the first tank body 5, i.e., a bottom ultrasonic model, Figure 3 (b) in the structure model is a model in which the ultrasonic vibrator 7 is located at the side of the first tank body 5, i.e., a side ultrasonic model. The bubble volume fraction on the electrode surface is calculated with respect to time by experiment for the bottom ultrasonic model, the side ultrasonic model and the model without ultrasonic, and the calculation results are shown in Figure 4 , wherein the vibration frequency of the ultrasonic is 20000 Hz, and the power is 120 W. It can be seen from the figure that the slope of the bubble volume fraction curve, i.e., the bubble detachment speed, presents a trend of first increasing and then decreasing, which indicates that with the increase of time, a part of the detached bubbles reattach to the electrode surface, so that the bubble detachment speed decreases. The bubble detachment speed of the bottom ultrasonic model is greater than that of the model without ultrasonic, and the bubble detachment speed of the model without ultrasonic is greater than that of the side ultrasonic model. When the ultrasonic vibrator 7 is arranged at the bottom, the disturbance of the ultrasonic to the bubbles is consistent with the direction of the buoyancy of the bubbles, which can accelerate the detachment of the bubbles. When the ultrasonic vibrator 7 is arranged at the side, the disturbance of the ultrasonic to the bubbles is perpendicular to the direction of the buoyancy of the bubbles, so that more detached bubbles from the electrode surface reattach to the electrode surface. The improper arrangement of the position of the ultrasonic vibrator 7 will affect the detachment of the bubbles, and thus the performance of the electrolytic cell is deteriorated.

[0054] II. Comparison between the flexible wall 2 and the existing rigid wall electrolytic cell

[0055] A structure model as shown in Figure 5 is constructed, wherein Figure 5 (a) in the structure model is a rigid wall model, Figure 5 (b) in the structure model is a flexible wall model. The bubble volume fraction on the electrode surface is calculated with respect to time by experiment for the two models, and the calculation results are shown inFigure 6 The vibration frequency of the flexible wall surface is 200 Hz, and the amplitude is 2.25 mm. As can be seen from the figure, for the flexible wall surface model, the bubble volume fraction on the electrode surface is reduced to zero at 0.0015 seconds, while the bubble volume fraction on the electrode surface of the rigid wall surface model is 0.995 at this time. The flexible wall structure proposed in the present application can greatly improve the bubble detachment speed on the electrode surface, reduce the electrolysis voltage, and improve the electrolysis efficiency.

[0056] III. Performance comparison between the opposite model and the same model

[0057] The structure model as shown in Figure 7 is constructed, wherein Figure 7 (a) is a model in which the first electrolyte inlet 51 and the oxygen gas outlet 52 are located on the two sides of the positive electrode 3, i.e. the opposite model, Figure 7 (b) is a model in which the first electrolyte inlet 51 and the oxygen gas outlet 52 are located on the same side of the positive electrode 3, i.e. the same model. The internal flow field of the two models is calculated by experiment as shown in Figure 8 , wherein Figure 8 (a) in the figure is the internal flow field diagram of the opposite model, Figure 8 (b) in the figure is the internal flow field diagram of the same model. As can be seen from the figure, when the first electrolyte inlet 51 and the oxygen gas outlet 52 are located on the two sides of the positive electrode 3, respectively, the flow of the electrolyte in the electrolytic cell will form a large range of vortexes on the two sides and the bottom of the positive electrode 3, which is beneficial to flushing the electrode surface and accelerating the bubble detachment; when the first electrolyte inlet 51 and the oxygen gas outlet 52 are on the same side of the positive electrode 3, most of the electrolyte is directly discharged, and the disturbance to the internal flow field is small.

[0058] Figure 9 The figure is a comparison diagram of the turbulent kinetic energy in the electrolytic cell of the opposite model and the same model at different inlet flow rates. As can be seen from the figure, compared with the same model, the average turbulent kinetic energy in the electrolytic cell of the opposite model can be increased by more than 60%, which greatly improves the bubble removal effect and further improves the electrolysis performance of the electrolytic cell.

[0059] IV. Performance comparison of electrolyte inlet position

[0060] The structure model as shown in Figure 10 is constructed, i.e. the performance comparison diagram of the opposite model when the first electrolyte inlet 51 is located at different positions of the first tank body 5; wherein Figure 10 (a) in the figure is a model in which the first electrolyte inlet 51 is located on the top surface of the first tank body 5, Figure 10 (b) in the figure is a model in which the first electrolyte inlet 51 is located on the side surface of the first tank body 5, Figure 10 (c) in the figure is a model in which the first electrolyte inlet 51 is located on the bottom surface of the first tank body 5. Figure 11The graphs show the turbulent kinetic energy comparison of the first electrolyte inlet 51 at the top, side, and bottom surfaces of the electrolyzer under different inlet flow rates. The graphs show that the turbulent kinetic energy of the bottom model is greater than that of the side model, which in turn is greater than that of the top model. Because the top model is closer to the outlet, some fluid is discharged directly from the outlet and does not enter the central region of the first tank 5, resulting in a lower turbulent kinetic energy compared to the bottom model. However, compared to the same-side models, the average turbulent kinetic energy within the electrolyzer is increased in all three opposite-side models, which helps to improve the electrolytic performance of the electrolyzer.

[0061] Example 2

[0062] This invention also provides another ultrasonic-assisted compression forced circulation electrolyzer, which is a solid polymer electrolyzer, such as... Figure 12 As shown, the electrolytic cell includes an electrolytic cell shell 1, a flexible wall 2, an ultrasonic transducer 7, and a membrane electrode 9. The electrolytic cell shell 1 and the flexible wall 2 together form the electrolytic cell body. By mechanically squeezing the flexible wall 2, the internal pressure difference of the electrolytic cell is changed, disturbing the electrolyte and accelerating the detachment of bubbles from the electrode surface. The membrane electrode 9 is located inside the electrolytic cell body, with its two ends connected to the top and bottom of the electrolytic cell shell 1, respectively, dividing the electrolytic cell body into a first tank body 5 and a second tank body 6. The membrane electrode 9 is located on one side of the first tank body 5 as the positive electrode, used to cause the hydroxide ions to undergo an oxidation reaction at the positive electrode of the membrane electrode 9, where the hydroxide ions lose electrons to produce oxygen. The membrane electrode 9 is located on one side of the second tank body 6 as the negative electrode, used to cause the hydrogen ions to undergo a reduction reaction at the negative electrode of the membrane electrode 9, where the hydrogen ions gain electrons to produce hydrogen gas. The electrolytic cell shell 1 has a first electrolyte inlet 51 and an oxygen outlet 52 at the position corresponding to the first tank 5, and a second electrolyte inlet 61 and a hydrogen outlet 62 at the position corresponding to the second tank 6. One-way valves are provided on the first electrolyte inlet 51, oxygen outlet 52, second electrolyte inlet 61, and hydrogen outlet 62. When the flexible wall 2 is compressed, forced circulation is formed within the electrolytic cell through the one-way valves on these valves. In this embodiment, the ultrasonic transducer 7 is preferably located at the bottom of the first tank 5 and the second tank 6. Compared to its location on the other walls of the electrolytic cell shell, this arrangement can accelerate the detachment speed of bubbles from the electrode surface. It is understood that the electrolytic cell shell 1 in this invention provides support for the flexible wall 2, the ultrasonic transducer 7, and the membrane electrode 9. The relative positions of the flexible wall 2 and the ultrasonic transducer 7 are not particularly required and are not limited to the specific positions in this embodiment.

[0063] Compared with the existing electrolytic cell only adding an ultrasonic field, the application accelerates the bubble to separate from the electrode surface through the following three aspects: 1. The electrolytic cell tank is formed by the electrolytic cell shell 1 and the flexible wall 2, and the pressure difference in the electrolytic cell is changed by mechanically extruding the flexible wall 2, so as to disturb the electrolyte and accelerate the bubble to separate from the surface of the positive electrode 3 and the negative electrode 4 or the positive electrode and the negative electrode of the membrane electrode 9; 2. The one-way valve is installed on the first electrolyte inlet 51, the oxygen gas outlet 52, the second electrolyte inlet 61 and the hydrogen gas outlet 62, and when the flexible wall 2 is extruded, the forced circulation flow is formed in the electrolytic cell through the one-way valve; 3. The ultrasonic vibrator 7 is arranged at the bottom of the first tank 5 and the second tank 6, and the cavitation effect is formed in the electrolyte by the high-frequency vibration of the ultrasonic vibrator 7, so as to disturb the electrolyte, flush the surface of the positive electrode 3 and the negative electrode 4 or the positive electrode and the negative electrode of the membrane electrode 9, affect the bubble movement behavior in the electrolytic cell and accelerate the bubble to separate from the electrode surface. Specifically, the mechanical extrusion process of the reciprocating pump on the flexible wall 2 increases the pressure in the electrolytic cell, so that the one-way valves of the oxygen gas outlet 52 and the hydrogen gas outlet 62 are opened, and the generated oxygen and hydrogen are respectively discharged from the electrolytic cell through the oxygen gas outlet 52 and the hydrogen gas outlet 62 with the electrolyte; at this time, the electrolyte flows to the two outlets and flushes the surface of the positive electrode 3 and the negative electrode 4 or the positive electrode and the negative electrode of the membrane electrode 9, so that the bubbles attached to the surface are discharged from the electrolytic cell. In the recovery process of the flexible wall 2, the pressure in the electrolytic cell is reduced, and at this time, the one-way valves of the first electrolyte inlet 51 and the second electrolyte inlet 61 are opened, so as to supplement the electrolyte in the electrolytic cell and form a circulation loop. The coupling effect of the mechanical extrusion of the flexible wall 2, the high-frequency vibration of the ultrasonic vibrator 7 and the forced circulation flow formed by the one-way valves can improve the working efficiency of the ultrasonic field, reduce the residence time of the bubbles and increase the yield of hydrogen and oxygen. Without additional pump liquid, the compression-recovery process of the flexible wall can realize the circulation flow of the electrolyte.

[0064] The above description is only used to illustrate the technical solutions of the application, not to limit them. For ordinary professional technicians in the field, the specific technical solutions described in the above embodiments can be modified or some technical features can be replaced, and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions protected by the application.

Claims

1. An ultrasonic-assisted compression-type forced circulation electrolytic cell, characterized in that: It includes an electrolytic cell shell (1), a flexible wall (2), a positive electrode (3), and a negative electrode (4); The electrolytic cell shell (1) and the flexible wall (2) together form the electrolytic cell body; The electrolytic cell is provided with a diaphragm (8) inside. The two ends of the diaphragm (8) are connected to the top and bottom of the electrolytic cell shell (1) respectively, dividing the electrolytic cell into a first cell (5) and a second cell (6). The positive electrode (3) is disposed on the inner wall of the electrolytic cell housing (1) and located in the first tank (5), and the negative electrode (4) is disposed on the inner wall of the electrolytic cell housing (1) and located in the second tank (6); The electrolytic cell shell (1) is provided with a first electrolyte inlet (51) and an oxygen outlet (52) at the position corresponding to the first tank body (5), and a second electrolyte inlet (61) and a hydrogen outlet (62) at the position corresponding to the second tank body (6); a one-way valve is provided on the first electrolyte inlet (51), the oxygen outlet (52), the second electrolyte inlet (61) and the hydrogen outlet (62); The first electrolyte inlet (51) and oxygen outlet (52) are located on both sides of the positive electrode (3); the second electrolyte inlet (61) and hydrogen outlet (62) are located on both sides of the negative electrode (4). An ultrasonic transducer (7) is provided at the bottom of both the first tank (5) and the second tank (6).

2. The ultrasonic-assisted compression forced circulation electrolytic cell according to claim 1, characterized in that: The first electrolyte inlet (51) is located at the bottom of the first tank (5), and the oxygen outlet (52) is located at the top of the first tank (5). The second electrolyte inlet (61) is located at the bottom of the second tank (6), and the hydrogen outlet (62) is located at the top of the second tank (6).

3. An ultrasonic-assisted compression-type forced circulation electrolytic cell according to claim 1 or 2, characterized in that: The ultrasonic transducers (7) are respectively disposed on the outer walls of the bottom of the first tank (5) and the second tank (6).

4. An ultrasonic-assisted compression-type forced circulation electrolytic cell, characterized in that: It includes an electrolytic cell shell (1), a flexible wall (2), an ultrasonic transducer (7), and a membrane electrode (9); The electrolytic cell shell (1) and the flexible wall (2) together form the electrolytic cell body; The membrane electrode (9) is located inside the electrolytic cell, and its two ends are connected to the top and bottom of the electrolytic cell shell (1) respectively, dividing the electrolytic cell into a first cell (5) and a second cell (6). The membrane electrode (9) is located on one side of the first tank (5) as a positive electrode, and the membrane electrode (9) is located on one side of the second tank (6) as a negative electrode. The electrolytic cell shell (1) is provided with a first electrolyte inlet (51) and an oxygen outlet (52) at the position corresponding to the first tank body (5), and a second electrolyte inlet (61) and a hydrogen outlet (62) at the position corresponding to the second tank body (6); a one-way valve is provided on the first electrolyte inlet (51), the oxygen outlet (52), the second electrolyte inlet (61) and the hydrogen outlet (62); Both the first tank (5) and the second tank (6) are equipped with ultrasonic transducers (7).

5. The ultrasonic-assisted compression forced circulation electrolytic cell according to claim 4, characterized in that: The first electrolyte inlet (51) is located at the bottom of the first tank (5), and the oxygen outlet (52) is located at the top of the first tank (5). The second electrolyte inlet (61) is located at the bottom of the second tank (6), and the hydrogen outlet (62) is located at the top of the second tank (6).

6. An ultrasonically assisted compression forced circulation electrolytic cell according to claim 4 or 5, characterized in that: The ultrasonic transducer (7) is disposed at the bottom of the first tank (5) and the second tank (6).

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