Method for detecting concentration of alkali liquor in water electrolysis hydrogen production device

Abstract

The invention relates to the technical field of water electrolysis hydrogen production, in particular to a method for detecting the concentration of alkali liquor in a water electrolysis hydrogen production device, which comprises the following steps of: leading out an alkali liquor concentration detection pipeline for receiving electrolyte from the inside of an electrolytic bath from the electrolytic bath of the water electrolysis hydrogen production device; the alkali liquor concentration detection pipeline is arranged on the electrolytic tank, so that electrolyte in the electrolytic tank enters the alkali liquor concentration detection pipeline and flows forwards, and a conductivity sensor inserted into the electrolyte in the alkali liquor concentration detection pipeline is arranged on the alkali liquor concentration detection pipeline; the conductivity sensor is used for detecting the conductivity of the electrolyte flowing in the alkali liquor concentration detection pipeline, so that the real-time online monitoring of the concentration of the electrolyte and the alkali liquor in the electrolytic bath is realized. Real-time on-line monitoring of the concentration of the alkali liquor in the electrolytic cell is achieved, and the accuracy of detection of the concentration of the alkali liquor in the electrolytic cell is improved.

Description

Technical Field

[0001] The invention relates to the technical field of water electrolysis hydrogen production, and in particular to a method for detecting alkaline solution concentration inside a water electrolysis hydrogen production device. Background Art

[0002] The water electrolysis hydrogen production device is a combination of equipment that uses alkaline water as raw material to produce hydrogen by electrolyzing water. The core equipment of the water electrolysis hydrogen production device is the electrolyzer, which is mainly assembled by plates, electrode meshes (anode meshes and cathode meshes), diaphragms, sealing gaskets and end plates, and forms an anode chamber and a cathode chamber inside it. When the electrolyzer is working, current is passed through the alkaline solution (electrolyte). After the water is electrolyzed, hydrogen is produced at the cathode and oxygen is produced at the anode. In this process, the water in the alkaline solution is continuously consumed by electrolysis, which causes the concentration of the alkaline solution to change. In order to maintain the stability of the alkaline solution concentration and improve the electrolysis efficiency, water replenishment is required during the electrolysis process. To this end, it is necessary to detect the concentration of the alkaline solution in the electrolyzer and reasonably replenish water according to the changes in the concentration of the alkaline solution.

[0003] At present, the main methods for detecting the concentration of alkali solution in the electrolytic cell are the gas-liquid separation level detection method and the discharged alkali solution detection concentration method. The gas-liquid separation level detection method is to determine the alkali concentration of the electrolyte in the electrolytic cell by detecting the change in the liquid level in the gas-liquid separation device of the water electrolysis hydrogen production device. Its disadvantage is that the detection stability is poor, and there is often a large difference with the actual alkali concentration. The discharged alkali solution detection concentration method is to detect the alkali concentration of the electrolyte discharged from the electrolytic cell. It is an offline detection method. Its disadvantage is that it cannot monitor the dynamic changes of the alkali concentration in the electrolytic cell in real time online, which may cause delays in the water replenishment operation, thereby affecting the performance of the electrolytic cell.

[0004] In addition, considering that the alkali concentration distribution in various places in the electrolytic cell is not uniform during actual operation, the existing alkali concentration detection method mainly detects the alkali concentration at the height position of the alkali outlet of the electrolytic cell, and cannot make a relatively accurate comprehensive evaluation of the alkali concentration and distribution at various height positions in the electrolytic cell. Accurately grasping the alkali concentration and distribution of various places in the electrolytic cell is not only conducive to the precise water replenishment operation of the electrolytic cell that is officially put into use, but also more conducive to the continuous improvement of the structural design of the new electrolytic cell in the research and development trial stage, thereby helping to develop high-performance electrolytic cells with more uniform internal alkali concentration distribution. Summary of the invention

[0005] In order to solve the above problems, the present invention proposes a method for detecting the concentration of alkaline solution in a water electrolysis hydrogen production device, aiming to realize real-time online monitoring of the concentration of alkaline solution in the electrolytic cell and improve the accuracy of the detection of the concentration of alkaline solution in the electrolytic cell. The specific technical solution is as follows: A method for detecting the internal alkali concentration of a water electrolysis hydrogen production device is provided. An alkali concentration detection pipeline for receiving electrolyte from the electrolytic cell is led out from the electrolytic cell of the water electrolysis hydrogen production device, so that the electrolyte in the electrolytic cell enters the alkali concentration detection pipeline and flows forward, and a conductivity sensor is arranged on the alkali concentration detection pipeline and inserted into the electrolyte in the alkali concentration detection pipeline. The conductivity of the electrolyte flowing in the alkali concentration detection pipeline is detected by using the conductivity sensor, so as to realize real-time online monitoring of the alkali concentration of the electrolyte in the electrolytic cell.

[0006] As one of the preferred schemes for setting up the alkali solution concentration detection pipeline in the present invention, the alkali solution concentration detection pipeline is an electrolytic cell liquid outlet main pipeline arranged between the liquid outlet of the electrolytic cell and the liquid inlet of the alkali solution heat exchanger of the gas-liquid separator of the water electrolysis hydrogen production device, that is, the original electrolytic cell liquid outlet main pipeline is used as the alkali solution concentration detection pipeline, and the conductivity sensor is arranged on the electrolytic cell liquid outlet main pipeline to realize real-time online monitoring of the electrolyte alkali solution concentration in the electrolytic cell.

[0007] As the second preferred scheme for setting up the alkali solution concentration detection pipeline in the present invention, the alkali solution concentration detection pipeline is a main detection pipeline from the liquid outlet position of the alkali solution heat exchanger of the gas-liquid separator of the electrolytic cell to the inlet of the electrolytic cell, and the conductivity sensor is arranged on the main detection pipeline to realize real-time online monitoring of the alkali solution concentration of the electrolyte in the electrolytic cell.

[0008] Preferably, the alkali solution concentration detection pipeline is provided with a first check valve, an electrolyte flow detection box and a second check valve which are connected in sequence according to the flow direction of the electrolyte, the conductivity sensor is arranged on the electrolyte flow detection box, and the detection probe of the conductivity sensor is inserted into the electrolyte inside the electrolyte flow detection box.

[0009] Preferably, a filter is also provided on the alkali solution concentration detection pipeline.

[0010] More preferably, the alkali solution concentration detection pipeline is provided with a first ball valve, a filter, a first check valve, an electrolyte flow detection box, a second check valve and a second ball valve in sequence according to the flow direction of the electrolyte, the conductivity sensor is arranged on the electrolyte flow detection box, and the detection probe of the conductivity sensor is inserted into the electrolyte inside the electrolyte flow detection box.

[0011] Preferably, the filter is a basket filter, a Y-type filter, a T-type filter, or the like.

[0012] In order to improve the accuracy of conductivity detection, a temperature detection sensor is provided on the alkali solution concentration detection pipeline for detecting the electrolyte temperature in the alkali solution concentration detection pipeline to achieve conductivity detection temperature compensation; the conductivity sensor and the temperature detection sensor are respectively connected to the conductivity controller.

[0013] Preferably, the temperature detection sensor is arranged on the alkali solution concentration detection pipeline at a position close to the electrolyte flow detection box.

[0014] In the present invention, the conductivity controller is a conductivity controller with a display device, which can be used to directly display the conductivity of the alkali solution in the control program.

[0015] Preferably, a bypass pipeline is connected between the two ends of the alkali solution concentration detection pipeline, and a bypass valve is provided on the bypass pipeline.

[0016] Preferably, the bypass valve is a ball valve.

[0017] As a further improvement of the present invention, the electrolyte flow detection box is a cross-shaped four-way tube, and the cross-shaped four-way tube is connected in series to the alkali solution concentration detection pipeline through the longitudinal tube bodies at its left and right ends. The conductivity sensor is installed at the pipe mouth of one of the transverse tube bodies at the upper and lower ends of the cross-shaped four-way tube, and the detection probe of the conductivity sensor is inserted into the inner center of the cross-shaped four-way tube; a sensor probe surface contaminant refresher for regularly refreshing and removing contaminants on the surface of the detection probe of the conductivity sensor is also provided on the cross-shaped four-way tube, and the sensor probe surface contaminant refresher includes a stirring motor installed at the pipe mouth of another transverse tube body of the transverse tube bodies at the upper and lower ends of the cross-shaped four-way tube, a rotating disk fixed on the motor shaft of the stirring motor, and a number of stirring scrapers erected circumferentially on the rotating disk and arranged on the periphery of the detection probe of the conductivity sensor.

[0018] As a further improvement of the present invention, a bellows-type cover is provided at the pipe mouth of the transverse pipe body for installing the surface dirt refresher of the sensor probe, and the stirring motor is fixed on the top of the bellows-type cover; a plurality of ultrasonic vibrators are also provided on the top of the bellows-type cover, and the ultrasonic vibrators are externally connected to an ultrasonic generator.

[0019] Preferably, the bellows type cover shell includes a bellows body, a cover plate arranged at the upper end of the bellows body as the top of the bellows type cover shell, and a flange arranged at the lower end of the bellows body and fixedly connected to the upper end of the cross-shaped four-way pipe; a number of guide rods located on the periphery of the bellows body are vertically arranged downward on the lower end surface of the cover plate, and a number of guide holes are correspondingly arranged on the flange, and the guide rods are inserted into the guide holes; a compression spring is also sheathed on the outer circle of a section of the guide rod located between the cover plate and the flange.

[0020] According to the actual electrolysis working conditions, the conductivity test can be carried out under the condition of electrolyte stirring and ultrasonic vibration cleaning, or the conductivity test can be carried out under the condition of electrolyte stirring stopped and ultrasonic vibration cleaning stopped.

[0021] As a third preferred solution for the arrangement of the alkali solution concentration detection pipeline in the present invention, the electrolytic cell of the water electrolysis hydrogen production device is provided with a number of electrode plates for supporting electrode meshes and stacked and clamped in sequence through sealing gaskets, the electrode plates comprising a main electrode plate and an electrode frame connected to the outer edge of the main electrode plate; at least one of the electrode plates is provided with an internal electrolyte balance sampler for online balanced sampling of electrolyte from different height positions inside the electrolytic cell, the alkali solution concentration detection pipeline is an external sampling pipeline arranged outside the electrolytic cell and connected to the internal electrolyte balance sampler; the internal electrolyte balance sampler comprises a sampling lead-out hole opened on the electrode frame, a groove arranged on the main electrode plate along the up and down directions, and a sampling tube embedded in the groove, the upper end of the sampling tube is connected to the sampling lead-out hole on the electrode frame; sampling introduction holes are provided on the tube wall at least at the upper, middle and lower positions of the sampling tube.

[0022] Preferably, a pair of internal electrolyte balance samplers are correspondingly arranged on a pair of electrode plates on both sides of the electrolytic cell; the two ends of the external sampling pipeline are correspondingly connected between the sampling lead-out holes of the pair of internal electrolyte balance samplers, and a circulation pump is arranged on the external sampling pipeline.

[0023] More preferably, the electrode plates in the electrolytic cell are divided into two groups, A and B, and the electrode plates in group A and group B of the two groups are arranged alternately in sequence; the sampling lead-out holes on the electrode plates in group A are interconnected to form a sampling lead-out A channel, and the sampling lead-out holes on the electrode plates in group B are interconnected to form a sampling lead-out B channel.

[0024] In the present invention, a sealing gasket A through hole for realizing the sampling lead-out A channel passing through the sealing gasket is provided on the sealing gasket located between two adjacent pole frames, and a sealing gasket B through hole for realizing the sampling lead-out B channel passing through the sealing gasket is also provided on the sealing gasket located between two adjacent pole frames.

[0025] More preferably, in order to better grasp the alkali solution concentration distribution at various locations inside the newly designed electrolytic cell during the research and development and trial production stages, only one sampling introduction hole at a specified height position (instead of multiple sampling introduction holes) can be set on the sampling tube of each electrode plate, and at the same time, a separate sampling loop is set between two adjacent pairs of electrode plates and the external sampling pipeline (the sampling introduction holes on the sampling tubes on the same pair of electrode plates have the same height, and the sampling introduction holes on the sampling tubes not on the same pair of electrode plates have different height positions), so that the alkali solution concentration distribution at different height positions inside the electrolytic cell can be measured separately, which is conducive to further improving the electrolytic cell structure during the research and development and trial production stages, so that the alkali solution concentration distribution inside the electrolytic cell is more balanced.

[0026] In addition, a separate sampling loop can also be set for each electrode plate. In this case, it is best to break the sampling tube of the electrode plate at a certain height to form a fracture (replacing the multiple sampling introduction holes on the original sampling tube, that is, no sampling introduction holes are set, and the break is directly used as the alkali solution sampling introduction position), and at the same time, the two lower ends of the sampling tube correspond to the sampling lead-out holes at the upper and lower ends of the electrode frame, and the upper and lower sampling lead-out holes are correspondingly connected to the two ends of the external sampling pipeline, thereby forming a separate sampling loop. By setting the fracture heights of the sampling tubes of different electrodes to be different from each other, the concentration of alkali solution at different heights in the electrolytic cell can be detected separately.

[0027] The beneficial effects of the present invention are: First, a method for detecting the concentration of alkali solution inside a water electrolysis hydrogen production device of the present invention realizes real-time online monitoring of the concentration of alkali solution in the electrolytic cell and improves the accuracy of the detection of the concentration of alkali solution in the electrolytic cell by leading out a alkali solution concentration detection pipeline for receiving the electrolyte from the electrolytic cell on the electrolytic cell of the water electrolysis hydrogen production device, and arranging a conductivity sensor connected to a conductivity controller on the alkali solution concentration detection pipeline. By accurately and in real time monitoring the conductivity of the alkali solution in the electrolytic cell, it is helpful to timely judge the condition of the alkali solution and prevent the increase of energy consumption fluctuation caused by excessive changes in the alkali solution concentration.

[0028] Secondly, the method for detecting the alkali solution concentration inside a water electrolysis hydrogen production device of the present invention provides a variety of technical solutions for setting up the alkali solution concentration detection pipeline, and provides a good design concept for online real-time monitoring of the alkali solution concentration in the electrolytic cell.

[0029] Third, in a method for detecting the concentration of alkaline solution inside a water electrolysis hydrogen production device of the present invention, a sensor probe surface dirt refresher is provided at the conductivity sensor part, and the stirring scraper on the sensor probe surface dirt refresher can stir up violent rotating waves around the sensor probe in the electrolyte flow detection box (cross-shaped four-way pipe) when rotating, and combined with the ultrasonic cleaning energy acting on the electrolyte, it plays a role in strongly washing the surface of the sensor probe, thereby solving the problem that the sensor probe of the conductivity sensor is easily affected by dirt adhesion when the electrolytic cell works for a long time, resulting in a decrease in measurement accuracy. This improves the stability of conductivity detection and the reliability of long-term operation.

[0030] Fourthly, a method for detecting the internal alkali solution concentration of a water electrolysis hydrogen production device of the present invention can sample alkali solution at different heights including the top, middle and bottom inside the electrolytic cell by setting an internal electrolyte balance sampler, thereby overcoming the disadvantage that the conventional alkali solution concentration detection method can only sample the alkali solution concentration at a height position close to the alkali solution outlet of the electrolytic cell, thereby being able to make a more objective and accurate comprehensive evaluation of the alkali solution concentration inside the electrolytic cell, realizing the optimization of the water replenishment operation, and further improving the performance of the electrolytic cell.

[0031] Fifth, a method for detecting the internal alkali solution concentration of a water electrolysis hydrogen production device of the present invention can realize the separate detection of the alkali solution concentration at different height positions inside the electrolytic cell by setting a separate sampling loop between two adjacent pairs of electrode plates and the external sampling pipeline, or setting a separate sampling loop between each electrode plate and the external sampling pipeline. This is beneficial for fully understanding the distribution of alkali solution concentration at various locations inside the newly designed electrolytic cell during the research and development and trial production stages, so that the structural design of the electrolytic cell can be improved in a targeted manner, and a high-performance electrolytic cell with a more uniform internal alkali solution concentration distribution can be developed. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the overall principle of a method for detecting the concentration of alkaline solution inside a water electrolysis hydrogen production device of the present invention; Figure 2 The main pipeline of the electrolytic cell is used as Figure 1 Application diagram of the alkali solution concentration detection pipeline; Figure 3 The main detection pipeline is led out from the liquid outlet of the alkali liquid heat exchanger of the gas-liquid separator of the electrolytic cell, and the main detection pipeline is used as Figure 1 Application diagram of the alkali solution concentration detection pipeline; Figure 4 is Figure 1 to Figure 3 A schematic diagram of the structure in which a conductivity sensor and a dirt refresher on the surface of a sensing probe are arranged on an electrolyte flow detection box (a cross-shaped four-way pipe); Figure 5It is one of the structural schematic diagrams of setting the internal electrolyte balance sampler on the plate (the plate belongs to the A group plate); Figure 6 The second structural diagram of the internal electrolyte balance sampler arranged on the plate (the plate belongs to the plate of group B); Figure 7 It is a bulk structure schematic diagram of a water electrolysis hydrogen production device in which an electrolyzer provided with an internal electrolyte balance sampler is connected to an external sampling pipeline to form a sampling electrolyte circulation loop; Figure 8 It is a schematic diagram of the circumferential position of the sampling lead-out channel A and the sampling lead-out channel B located on the end face of the pole frame after the electrolytic cell is assembled; Fig. 9 It is a schematic diagram of the structure of setting an independent sampling circuit on a single plate.

[0033] In the figure: 01, conductivity sensor, 02, electrolyte flow detection box (cross-shaped four-way pipe), 03, longitudinal tube body, 04, transverse tube body, 05, sensor probe surface dirt refresher, 06, stirring motor, 07, motor shaft, 08, rotating disk, 09, detection probe, 10, stirring scraper, 11, ultrasonic vibrator, 12, bellows body, 13, cover plate, 14, flange, 15, guide rod, 16, compression spring, 17, alkali solution concentration detection pipeline.

[0034] In the figure: 20, internal electrolyte balance sampler, 21, electrode mesh, 22, sealing gasket, 23, electrode plate, 24, main electrode plate, 25, electrode frame, 26, external sampling pipeline, 27, sampling lead-out hole, 28, groove, 29, sampling tube, 30, sampling introduction hole, 31, circulation pump, 32, group A electrode plate, 33, group B electrode plate, 34, sampling lead-out channel A, 35, sampling lead-out channel B, 36, sealing gasket A through hole, 37, sealing gasket B through hole, 38, diaphragm, 39, hydrogen gas channel hole, 40, oxygen gas channel hole, 41, alkali solution inlet hole, 42, sampling tube fracture. DETAILED DESCRIPTION

[0035] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0036] like Figures 1 to 9The figure shows an embodiment of a method for detecting the internal alkali solution concentration of a water electrolysis hydrogen production device of the present invention, comprising leading out an alkali solution concentration detection pipeline on the electrolytic cell of the water electrolysis hydrogen production device for receiving the electrolyte from the electrolytic cell, so that the electrolyte in the electrolytic cell enters the alkali solution concentration detection pipeline and flows forward, and arranging a conductivity sensor on the alkali solution concentration detection pipeline for being inserted into the electrolyte in the alkali solution concentration detection pipeline, and detecting the conductivity of the electrolyte flowing in the alkali solution concentration detection pipeline by using the conductivity sensor, thereby realizing real-time online monitoring of the alkali solution concentration of the electrolyte in the electrolytic cell.

[0037] As one of the preferred schemes for the setting of the alkali solution concentration detection pipeline in this embodiment, the alkali solution concentration detection pipeline is an electrolytic cell liquid outlet main pipeline arranged between the liquid outlet of the electrolytic cell and the liquid inlet of the alkali solution heat exchanger of the gas-liquid separator of the water electrolysis hydrogen production device, that is, the original electrolytic cell liquid outlet main pipeline is used as the alkali solution concentration detection pipeline, and the conductivity sensor is arranged on the electrolytic cell liquid outlet main pipeline to realize real-time online monitoring of the electrolyte alkali solution concentration in the electrolytic cell.

[0038] As the second preferred scheme for setting up the alkali solution concentration detection pipeline in this embodiment, the alkali solution concentration detection pipeline is a main detection pipeline from the liquid outlet position of the alkali solution heat exchanger of the gas-liquid separator of the electrolytic cell to the inlet of the electrolytic cell, and the conductivity sensor is arranged on the main detection pipeline to realize real-time online monitoring of the alkali solution concentration of the electrolyte in the electrolytic cell.

[0039] Preferably, the alkali solution concentration detection pipeline is provided with a first check valve, an electrolyte flow detection box and a second check valve which are connected in sequence according to the flow direction of the electrolyte, the conductivity sensor is arranged on the electrolyte flow detection box, and the detection probe of the conductivity sensor is inserted into the electrolyte inside the electrolyte flow detection box.

[0040] Preferably, a filter is also provided on the alkali solution concentration detection pipeline.

[0041] More preferably, the alkali solution concentration detection pipeline is provided with a first ball valve, a filter, a first check valve, an electrolyte flow detection box, a second check valve and a second ball valve in sequence according to the flow direction of the electrolyte, the conductivity sensor is arranged on the electrolyte flow detection box, and the detection probe of the conductivity sensor is inserted into the electrolyte inside the electrolyte flow detection box.

[0042] Preferably, the filter is a basket filter, a Y-type filter, a T-type filter, or the like.

[0043] In order to improve the accuracy of conductivity detection, a temperature detection sensor is provided on the alkali solution concentration detection pipeline for detecting the electrolyte temperature in the alkali solution concentration detection pipeline to achieve conductivity detection temperature compensation; the conductivity sensor and the temperature detection sensor are respectively connected to the conductivity controller.

[0044] Preferably, the temperature detection sensor is arranged on the alkali solution concentration detection pipeline at a position close to the electrolyte flow detection box.

[0045] In this embodiment, the conductivity controller is a conductivity controller with a display device, which can be used to directly display the conductivity of the alkali solution in the control program.

[0046] Preferably, a bypass pipeline is connected between the two ends of the alkali solution concentration detection pipeline, and a bypass valve is provided on the bypass pipeline.

[0047] Preferably, the bypass valve is a ball valve.

[0048] As a further improvement of this embodiment, the electrolyte flow detection box 02 is a cross-shaped four-way tube, and the cross-shaped four-way tube is connected in series to the alkali solution concentration detection pipeline 17 through the longitudinal tube bodies 03 at its left and right ends. The conductivity sensor 01 is installed at the pipe mouth of one of the transverse tube bodies 04 at the upper and lower ends of the cross-shaped four-way tube, and the detection probe 09 of the conductivity sensor 01 is inserted into the inner center of the cross-shaped four-way tube; the cross-shaped four-way tube is also provided with a sensor probe surface contaminant refresher 05 for regularly refreshing and removing the contaminants on the surface of the detection probe 09 of the conductivity sensor 01, and the sensor probe surface contaminant refresher 05 includes a stirring motor 06 installed at the pipe mouth of another transverse tube body of the transverse tube bodies 04 at the upper and lower ends of the cross-shaped four-way tube, a rotating disk 08 fixed on the motor shaft 07 of the stirring motor 06, and a number of stirring scrapers 10 erected circumferentially on the rotating disk 08 and arranged on the periphery of the detection probe 09 of the conductivity sensor 01.

[0049] As a further improvement of the present embodiment, a bellows-type cover is provided at the pipe mouth of the transverse pipe body 04 for installing the surface dirt refresher 05 of the sensor probe, and the stirring motor 06 is fixed on the top of the bellows-type cover; a plurality of ultrasonic vibrators 11 are also provided on the top of the bellows-type cover, and the ultrasonic vibrators 11 are externally connected to an ultrasonic generator.

[0050] Preferably, the bellows type cover shell includes a bellows body 12, a cover plate 13 arranged at the upper end of the bellows body 12 as the top of the bellows type cover shell, and a flange 14 arranged at the lower end of the bellows body 12 and fixedly connected to the upper end pipe mouth of the cross-shaped four-way pipe; a number of guide rods 15 located on the periphery of the bellows body 12 are vertically arranged downward on the lower end surface of the cover plate 13, and a number of guide holes are correspondingly arranged on the flange 14, and the guide rods 15 are inserted into the guide holes; a compression spring 16 is also sheathed on the outer circle of a section of the guide rod 15 located between the cover plate 13 and the flange 14.

[0051] According to the actual electrolysis working conditions, the conductivity test can be carried out under the condition of electrolyte stirring and ultrasonic vibration cleaning, or the conductivity test can be carried out under the condition of electrolyte stirring stopped and ultrasonic vibration cleaning stopped.

[0052] As the third preferred solution for the arrangement of the alkali solution concentration detection pipeline in this embodiment, the electrolytic cell of the water electrolysis hydrogen production device is provided with a number of electrode plates 23 for supporting the electrode mesh 21 and stacked and clamped in sequence through sealing gaskets 22, wherein the electrode plates 23 include a main electrode plate 24 and an electrode frame 25 connected to the outer edge of the main electrode plate 24; at least one of the electrode plates 23 is provided with an internal electrolyte balance sampler 20 for online balanced sampling of electrolyte from different height positions inside the electrolytic cell, and the alkali solution concentration detection pipeline 17 is An external sampling pipeline 26 is arranged outside the electrolytic cell and connected to the internal electrolyte balanced sampler 20; the internal electrolyte balanced sampler 20 includes a sampling lead-out hole 27 opened on the pole frame 25, a groove 28 arranged on the main pole plate 24 along the up and down directions, and a sampling tube 29 embedded in the groove 28, and the upper end of the sampling tube 29 is connected to the sampling lead-out hole 27 on the pole frame 25; sampling introduction holes 30 are opened on the tube wall of at least the upper, middle and lower positions of the sampling tube 29.

[0053] Preferably, a pair of internal electrolyte balance samplers 20 are correspondingly arranged on a pair of electrode plates 23 on both sides of the electrolytic cell; the two ends of the external sampling pipeline 26 are correspondingly connected between the sampling lead-out holes 27 of the pair of internal electrolyte balance samplers 20, and a circulation pump 31 is arranged on the external sampling pipeline 26.

[0054] More preferably, the electrode plates 23 in the electrolytic cell are divided into two groups, A and B, and the electrode plates 32 of group A and the electrode plates 33 of group B in the two groups are arranged alternately in sequence; the sampling lead-out holes 27 on the electrode plates 32 of group A are interconnected to form a sampling lead-out A channel 34, and the sampling lead-out holes on the electrode plates of group B are interconnected to form a sampling lead-out B channel 35.

[0055] In this embodiment, a sealing gasket A through hole 36 for enabling the sampling lead-out A channel 34 to pass through the sealing gasket 22 is provided on the sealing gasket 22 located between the two adjacent pole frames 25, and a sealing gasket B through hole 37 for enabling the sampling lead-out B channel 35 to pass through the sealing gasket 22 is also provided on the sealing gasket 22 located between the two adjacent pole frames 25.

[0056] More preferably, in order to better grasp the alkali solution concentration distribution at various locations inside the newly designed electrolytic cell during the research, development and trial production stages, only one sampling introduction hole 30 at a specified height position (instead of multiple sampling introduction holes) can be set on the sampling tube 29 of each electrode plate 23, and at the same time, a separate sampling circuit is set between two adjacent pairs of electrode plates 23 and the external sampling pipeline 26 (the sampling introduction holes 30 on the sampling tubes 29 on the same pair of electrode plates 23 have the same height, and the sampling introduction holes 30 on the sampling tubes 29 not on the same pair of electrode plates 23 have different height positions), so that the alkali solution concentration distribution at different height positions inside the electrolytic cell can be measured separately, which is conducive to further improving the electrolytic cell structure during the research, development and trial production stages, so that the alkali solution concentration distribution inside the electrolytic cell is more balanced.

[0057] In addition, if Fig. 9 As shown, a sampling circuit can also be set up separately for each electrode plate 23. In this case, it is best to break the sampling tube 29 of the electrode plate 23 at a certain height to form a fracture (replacing the multiple sampling introduction holes 30 on the original sampling tube 29, that is, no sampling introduction holes 30 are set, and the fracture is directly used as the alkali solution sampling introduction position), and at the same time, the two lower ends of the sampling tube 29 correspond to the sampling lead-out holes 27 at the upper and lower ends of the electrode frame 25, and the upper and lower sampling lead-out holes 27 are correspondingly connected to the two ends of the external sampling pipeline 26, thereby forming a separate sampling circuit. By setting the fracture heights of the sampling tubes 29 of different electrode plates 23 to be different from each other, the concentration of the alkali solution at different heights in the electrolytic cell can be detected separately.

[0058] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for detecting the concentration of alkaline solution inside a water electrolysis hydrogen production device, characterized in that: A alkali solution concentration detection pipeline is led out from the electrolytic cell of the water electrolysis hydrogen production device to receive the electrolyte from the electrolytic cell, so that the electrolyte in the electrolytic cell enters the alkali solution concentration detection pipeline and flows forward, and a conductivity sensor inserted into the electrolyte in the alkali solution concentration detection pipeline is arranged on the alkali solution concentration detection pipeline. The conductivity of the electrolyte flowing in the alkali solution concentration detection pipeline is detected by using the conductivity sensor, so as to realize real-time online monitoring of the alkali solution concentration of the electrolyte in the electrolytic cell.

2. The method for detecting the concentration of alkaline solution in a water electrolysis hydrogen production device according to claim 1, characterized in that: The alkali solution concentration detection pipeline is an electrolytic cell liquid outlet main pipeline arranged between the electrolytic cell liquid outlet and the liquid inlet of the alkali solution heat exchanger of the gas-liquid separator of the water electrolysis hydrogen production device, that is, the original electrolytic cell liquid outlet main pipeline is used as the alkali solution concentration detection pipeline, and the conductivity sensor is arranged on the electrolytic cell liquid outlet main pipeline to realize real-time online monitoring of the electrolyte alkali solution concentration in the electrolytic cell.

3. The method for detecting the concentration of alkaline solution in a water electrolysis hydrogen production device according to claim 1, characterized in that: The alkali solution concentration detection pipeline is provided with a first check valve, an electrolyte flow detection box and a second check valve which are connected in sequence according to the flow direction of the electrolyte. The conductivity sensor is arranged on the electrolyte flow detection box, and the detection probe of the conductivity sensor is inserted into the electrolyte inside the electrolyte flow detection box.

4. The method for detecting the concentration of alkaline solution in a water electrolysis hydrogen production device according to claim 3, characterized in that: The alkali solution concentration detection pipeline is provided with a first ball valve, a filter, a first check valve, an electrolyte flow detection box, a second check valve and a second ball valve in sequence according to the flow direction of the electrolyte. The conductivity sensor is provided on the electrolyte flow detection box, and the detection probe of the conductivity sensor is inserted into the electrolyte inside the electrolyte flow detection box.

5. The method for detecting the concentration of alkaline solution in a water electrolysis hydrogen production device according to claim 1, characterized in that: The alkali solution concentration detection pipeline is provided with a temperature detection sensor for detecting the electrolyte temperature in the alkali solution concentration detection pipeline to achieve conductivity detection temperature compensation; the conductivity sensor and the temperature detection sensor are respectively connected to the conductivity controller.

6. The method for detecting the concentration of alkaline solution in a water electrolysis hydrogen production device according to claim 1, characterized in that: A bypass pipeline is also connected between the two ends of the alkali solution concentration detection pipeline, and a bypass valve is arranged on the bypass pipeline.

7. The device for detecting the concentration of alkaline solution in a water electrolysis hydrogen production device according to claim 3, characterized in that: The electrolyte flow detection box is a cross-shaped four-way tube, which is connected in series to the alkali solution concentration detection pipeline through the longitudinal tube bodies at its left and right ends. The conductivity sensor is installed at the pipe mouth of one of the transverse tube bodies at the upper and lower ends of the cross-shaped four-way tube, and the detection probe of the conductivity sensor is inserted into the inner center of the cross-shaped four-way tube; the cross-shaped four-way tube is also provided with a sensor probe surface dirt refresher for regularly refreshing and removing dirt on the surface of the detection probe of the conductivity sensor, and the sensor probe surface dirt refresher includes a stirring motor installed at the pipe mouth of another transverse tube body of the transverse tube bodies at the upper and lower ends of the cross-shaped four-way tube, a rotating disk fixed on the motor shaft of the stirring motor, and a number of stirring scrapers erected circumferentially on the rotating disk and arranged on the periphery of the detection probe of the conductivity sensor.

8. The device for detecting the concentration of alkaline solution in a water electrolysis hydrogen production device according to claim 7, characterized in that: A bellows-type cover is provided at the pipe mouth of the transverse pipe body for installing the surface dirt refresher of the sensor probe, and the stirring motor is fixed on the top of the bellows-type cover; a plurality of ultrasonic vibrators are also provided on the top of the bellows-type cover, and the ultrasonic vibrators are externally connected to an ultrasonic generator.

9. The device for detecting the concentration of alkaline solution in a water electrolysis hydrogen production device according to claim 1, characterized in that: The electrolytic cell of the water electrolysis hydrogen production device is provided with a number of electrode plates for supporting electrode meshes and stacked and clamped in sequence through sealing gaskets, the electrode plates include a main electrode plate and an electrode frame connected to the outer edge of the main electrode plate; at least one of the electrode plates is provided with an internal electrolyte balance sampler for online balanced sampling of electrolyte from different height positions inside the electrolytic cell, the alkali solution concentration detection pipeline is an external sampling pipeline arranged outside the electrolytic cell and connected to the internal electrolyte balance sampler; the internal electrolyte balance sampler includes a sampling lead-out hole opened on the electrode frame, a groove arranged on the main electrode plate along the up and down direction, and a sampling tube embedded in the groove, the upper end of the sampling tube is connected to the sampling lead-out hole on the electrode frame; sampling introduction holes are opened on the tube wall at least at the upper, middle and lower positions of the sampling tube.

10. The device for detecting the concentration of alkaline solution in a water electrolysis hydrogen production device according to claim 1, characterized in that: A pair of internal electrolyte balance samplers are correspondingly arranged on a pair of electrode plates on both sides of the electrolytic cell; the two ends of the external sampling pipeline are correspondingly connected between the sampling lead-out holes of the pair of internal electrolyte balance samplers, and a circulation pump is arranged on the external sampling pipeline.

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