Testing device and method for hydrogen production through water electrolysis

Abstract

The invention relates to a testing device and method for hydrogen production through water electrolysis, the device comprises a water storage tank, a purification column, a conductivity tester, a circulating pump, an electrolytic bath, a first gas-liquid separator and a second gas-liquid separator, and the downstream of the circulating pump is provided with a first passage and a second passage; the first passage is communicated with the circulating pump and an anode inlet of the electrolytic bath, and the second passage is communicated with the circulating pump and an inlet of the first gas-liquid separator; the cathode outlet of the electrolytic cell is provided with a third passage and a fourth passage, the third passage is communicated with the cathode outlet of the electrolytic cell and the inlet of the second gas-liquid separator, and the fourth passage is communicated with the cathode outlet of the electrolytic cell and the water storage tank. The circulation loop is arranged at the cathode of the electrolytic cell, the problem that liquid permeates from the anode to the cathode in the electrolytic process is solved by controlling opening and closing of the valve, the liquid of the cathode of the electrode cell is recycled to the water storage tank and reused by the anode, water is saved, the electrolytic hydrogen production testing cost can be reduced, and the testing efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of hydrogen production by water electrolysis, and in particular to a testing device and method for hydrogen production by water electrolysis. Background Art

[0002] At present, there are three main ways to produce hydrogen by water electrolysis: alkaline water electrolysis, solid oxide water electrolysis and proton exchange membrane water electrolysis. Among them, solid oxide electrolysis has not yet entered commercialization; although the traditional alkaline electrolysis hydrogen production technology is mature, it has high production costs due to defects such as large equipment size, low efficiency and complex components; proton exchange membrane water electrolysis has the characteristics of high current density, strong flexibility, high efficiency and large energy capacity, which can better match renewable energy, and due to its compact structure, it can operate at a high pressure of up to 350 bar, which is conducive to the storage and transportation of hydrogen, and can effectively reduce the loss caused by compression and storage, and has excellent development prospects.

[0003] To realize the actual investment in proton exchange membrane water electrolysis hydrogen production technology, it is necessary to clarify the performance parameters of the electrolyzer. Therefore, during the research and development process of the proton exchange membrane electrolyzer, multiple verifications are required to clarify the key parameters of each component in the electrolyzer. However, during the test process, due to the structural limitations of the electrolyzer used for testing, the internal liquid will penetrate from the anode side to the cathode side, causing the liquid on the cathode side to rise, so effective means must be taken to discharge the liquid on the cathode side while avoiding pollution. Summary of the invention

[0004] In order to overcome the above-mentioned deficiencies of the prior art, the present application provides a testing device and method for producing hydrogen by electrolysis of water, which specifically adopts the following technical solutions:

[0005] A testing device for producing hydrogen by electrolyzing water, comprising a water storage tank, a purification column, a conductivity tester, a circulation pump, an electrolyzer, a first gas-liquid separator and a second gas-liquid separator, wherein the water storage tank, the purification column, the conductivity tester and the circulation pump are sequentially connected in series;

[0006] A first passage and a second passage are respectively provided downstream of the circulation pump, wherein the first passage is used to connect the circulation pump with the anode inlet of the electrolytic cell, and the second passage is used to connect the circulation pump with the inlet of the first gas-liquid separator; the liquid outlet of the first gas-liquid separator is connected to the water storage tank; wherein a first parallel point is provided on the first passage, one end of the second passage is connected to the first parallel point, and the other end of the second passage is connected to the inlet of the first gas-liquid separator;

[0007] The cathode outlet of the electrolytic cell is provided with a third passage and a fourth passage, wherein the third passage is used to connect the cathode outlet of the electrolytic cell with the inlet of the second gas-liquid separator, and the fourth passage is used to connect the cathode outlet of the electrolytic cell with the water storage tank; wherein a second parallel point is provided on the third passage, one end of the fourth passage is connected to the second parallel point, and the other end of the fourth passage is connected to the water storage tank.

[0008] Optionally: the first passage is provided with a first valve, and the first valve is arranged between the electrolytic cell and the first parallel point; the second passage is provided with a second valve, and the second valve is located between the first parallel point and the first gas-liquid separator.

[0009] Optionally: the third passage is provided with a third valve, and the third valve is arranged between the electrolytic cell and the second parallel point; the fourth passage is provided with a fourth valve, and the fourth valve is located between the second parallel point in the fourth passage and the water storage tank.

[0010] Optionally: the first valve and the second valve are both electric valves, and the conductivity tester controls the opening and closing states of the first valve and the second valve respectively.

[0011] Optionally: a fifth passage is provided at the anode outlet of the electrolytic cell, and one end of the fifth passage is connected to the anode outlet of the electrolytic cell, and the other end of the fifth passage is connected in parallel to a downstream position of the second valve in the second passage.

[0012] Optionally: a fluoride ion concentration monitor is provided at the inlet of the first gas-liquid separator, and the fluoride ion concentration monitor is used to monitor the fluoride ion concentration of the liquid flowing back to the water storage tank.

[0013] Optionally: a first dryer is provided at the gas outlet of the first gas-liquid separator, and the first dryer is used to dry the gas separated by the first gas-liquid separator.

[0014] Optionally: a second dryer is provided at the gas outlet of the second gas-liquid separator, and the second dryer is used to dry the gas separated by the second gas-liquid separator.

[0015] Furthermore, the present application also discloses a test method for producing hydrogen by electrolysis of water, which is tested using the test device as described above, and the test method comprises at least the following steps:

[0016] When conducting the test of hydrogen production by electrolysis of water, the first passage is kept open, the second passage is kept closed, and the liquid in the water storage tank is passed through the purification column, the conductivity tester, and the circulation pump in sequence, and then introduced into the anode inlet of the electrolytic cell;

[0017] The electrolyzer is powered on and performs hydrogen production operation, at which time the third passage remains open, the fourth passage remains closed, the gas produced by the anode of the electrolyzer is passed into the first gas-liquid separator through the fifth passage, and the gas produced by the cathode of the electrolyzer is passed into the second gas-liquid separator through the third passage;

[0018] After the test of hydrogen production by water electrolysis is completed, the third passage remains closed, the fourth passage remains open, and the liquid at the cathode of the electrolytic cell flows back to the water storage tank through the fourth passage.

[0019] Optional: Before conducting the water electrolysis hydrogen production test, keep the first passage closed and the second passage open, so that the liquid in the water storage tank passes through the purification column, the conductivity tester, and the circulation pump in sequence, and then enters the first gas-liquid separator and finally flows back to the water storage tank.

[0020] Beneficial Effects

[0021] The technical solution of this application has the following beneficial effects:

[0022] The test device of the present application sets a circulation loop at the cathode of the electrolytic cell, and controls the opening and closing of the valve to solve the problem of liquid penetration from the anode to the cathode during the electrolysis process, so as to recover the liquid at the cathode of the electrode cell to the water storage tank and reuse it at the anode to save water, thereby reducing the cost of electrolytic hydrogen production testing and improving testing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the structure of the test device for producing hydrogen by electrolysis of water in the embodiment of the present application.

[0024] The specific meanings of the reference numerals in the accompanying drawings:

[0025] 1-water storage tank; 2-purification column; 3-conductivity tester; 4-circulation pump; 5-first valve; 6-electrolyzer; 7-third valve; 8-second gas-liquid separator; 9-second dryer; 10-first dryer; 11-first gas-liquid separator; 12-fluoride ion concentration monitor; 13-second valve; 14-fourth valve. DETAILED DESCRIPTION

[0026] The present application is further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and cannot be used to limit the scope of protection of the present application. It should be noted that the following detailed descriptions are all exemplary and are intended to provide further explanation of the present application.

[0027] Combination Figure 1As shown, the embodiment of the present application specifically discloses a test device for producing hydrogen by electrolyzing water, including a water storage tank 1, a purification column 2, a conductivity tester 3, a circulation pump 4, an electrolytic cell 6, a first gas-liquid separator 11 and a second gas-liquid separator 8, and the water storage tank 1, the purification column 2, the conductivity tester 3 and the circulation pump 4 are sequentially connected in series. The water storage tank 1 is used to store the electrolyte to be introduced into the electrolytic cell 6; the purification column 2 is used to remove impurities and purify the electrolyte introduced into the electrolytic cell 6 to improve the purity of the electrolyte; the conductivity tester 3 is used to monitor the purity of the purified electrolyte to control whether to introduce the purified electrolyte into the electrolytic cell 6; and the circulation pump 4 provides a driving force for the flow of the electrolyte.

[0028] The first passage and the second passage are respectively provided downstream of the circulation pump 4, wherein the first passage is used to connect the circulation pump 4 with the anode inlet of the electrolytic cell 6; the second passage is used to connect the circulation pump 4 with the inlet of the first gas-liquid separator 11, wherein the first passage is provided with a first parallel point, one end of the second passage is connected to the first parallel point, and the other end is connected to the inlet of the first gas-liquid separator 11; the liquid outlet of the first gas-liquid separator 11 is connected to the water storage tank 1; further, in the embodiment of the present application, the first passage is provided with a first valve 5, wherein the first valve 5 is close to the anode inlet of the electrolytic cell 6, that is, the first valve is arranged between the electrolytic cell and the first parallel point; the second passage is provided with a second valve 13, wherein the second valve 13 is located at a downstream position close to the first parallel point on the second passage, that is, the second valve is located between the first parallel point and the first gas-liquid separator. Preferably, the first valve 5 and the second valve 13 can both be electric valves, and the opening and closing states of the first valve 5 and the second valve 13 are respectively controlled by the conductivity tester 3.

[0029] When the first valve 5 on the first passage is kept in an open state and the second valve 13 on the second passage is kept in a closed state, the electrolyte in the water storage tank 1 will pass through the purification column 2, the conductivity tester 3, the circulation pump 4 and the first passage in sequence, and enter the anode inlet of the electrolyzer 6, so that the electrolyte participates in the hydrogen production operation of the electrolyzer 6; and when the first valve 5 on the first passage is kept in a closed state and the second valve 13 on the second passage is kept in an open state, the electrolyte flowing through the circulation pump 4 will enter the first gas-liquid separator 11 through the second passage, and flow back to the water storage tank 1 through the first gas-liquid separator 11. It should be noted that when the electrolyte passes through the second passage, the first gas-liquid separator 11, and flows back to the water storage tank 1, the second passage and the first gas-liquid separator 11 constitute a purification circulation loop of the electrolyte. The degree of purification of the electrolyte is monitored by the conductivity tester 3. The electrolyte can be circulated through the purification column 2 for multiple times before electrolysis to produce hydrogen, and the electrolyte in the water storage tank 1 can be purified multiple times by the purification column 2 to improve the purity of the electrolyte. Of course, a fluoride ion concentration monitor 12 is further provided at the inlet position of the first gas-liquid separator 11, and the fluoride ion concentration of the liquid flowing back to the water storage tank 1 can be monitored by the fluoride ion concentration monitor 12 to achieve electrolyte purity monitoring.

[0030] In addition, the embodiment of the present application is provided with a third passage and a fourth passage at the cathode outlet of the electrolyzer 6, wherein the third passage is used to connect the cathode outlet of the electrolyzer 6 with the inlet of the second gas-liquid separator 8, and the fourth passage is used to connect the cathode outlet of the electrolyzer 6 with the water storage tank 1, and a second parallel point is provided on the third passage, one end of the fourth passage is connected to the second parallel point, and the other end is connected to the water storage tank 1. Further, the third passage is provided with a third valve 7, wherein the third valve 7 is close to the cathode outlet of the electrolyzer 6, that is, the third valve is arranged between the electrolyzer and the second parallel point; and the fourth passage is provided with a fourth valve 14, and the fourth valve 14 is located on the fourth passage between the second parallel point and the water storage tank 1. By controlling the opening and closing of the third valve 7 and the fourth valve 14, the discharge of products and the reflux of electrolyte in the process of electrolytic hydrogen production can be controlled. It should be understood that during the normal operation of water electrolysis hydrogen production, the electrolyte located at the anode side will gradually penetrate into the cathode side, resulting in an increase in the electrolyte on the cathode side of the electrolyzer 6. To avoid the cathode side electrolyte affecting the hydrogen production process, after water electrolysis hydrogen production is completed, the fourth valve 14 can be opened to partially return the electrolyte on the cathode side to the water storage tank 1, reducing the storage capacity of the cathode side electrolyte. In addition, due to the second gas-liquid separator 8, the product discharged from the cathode is subjected to gas-liquid separation (generally a mixture of hydrogen and electrolyte), and part of the electrolyte can be separated. After water electrolysis hydrogen production is completed, the third valve 7 can be closed, and the fourth valve 14 can be opened to allow the electrolyte separated by the second gas-liquid separator 8 to flow back to the second parallel point through part of the third path, and flow through the fourth path until it flows into the water storage tank 1, to save electrolyte.

[0031] More specifically, in the embodiment of the present application, the anode outlet of the electrolyzer 6 is connected to one end of the fifth passage, and the other end of the fifth passage is connected in parallel to the downstream position of the second valve 13 in the second passage, and finally the gas at the anode outlet of the electrolyzer 6 is passed into the first gas-liquid separator 11 for separation. When the electrolyzer 6 is in the process of hydrogen production, the electrolyte (generally water) is decomposed by direct current, and a reduction reaction occurs at the cathode, and the water molecules gain electrons to generate hydrogen; an oxidation reaction occurs at the anode, and the water molecules lose electrons to generate oxygen.

[0032] In order to timely remove the hydrogen and oxygen produced by the electrolyzer 6, the anode and cathode of the electrolyzer 6 are both provided with gas outlets, and the hydrogen located at the cathode of the electrolyzer 6 flows through the third passage from the gas outlet of the cathode and flows to the second gas-liquid separator 8. When hydrogen is produced in the electrolyzer 6, heat is generated and the electrolyte is heated, so that part of the electrolyte evaporates into steam and flows into the second gas-liquid separator 8 together with the hydrogen. The evaporated electrolyte steam can be liquefied and separated by the second gas-liquid separator 8. The gas outlet of the second gas-liquid separator 8 is provided with a second dryer 9, and the second dryer 9 can dry the hydrogen gas separated by the second gas-liquid separator 8. Similarly, the oxygen located at the anode of the electrolyzer 6 flows through the fifth passage from the gas outlet of the anode, and flows to the first gas-liquid separator 11 through the fluoride ion concentration monitor 12. The gas outlet of the first gas-liquid separator 11 is provided with a first dryer 10, and the first dryer 10 is used to dry the gas separated by the first gas-liquid separator 11.

[0033] Furthermore, based on the above-mentioned testing device, the present application also discloses a testing method for producing hydrogen by electrolysis of water, the testing method comprising at least the following steps:

[0034] When conducting the test of hydrogen production by electrolysis of water, the first passage is kept open, the second passage is kept closed, and the liquid in the water storage tank 1 is passed through the purification column 2, the conductivity tester 3, and the circulation pump 4 in sequence, and then introduced into the anode inlet of the electrolytic cell 6;

[0035] The electrolyzer 6 is powered on and performs hydrogen production operation. At this time, the third passage remains open, the fourth passage remains closed, the gas produced by the anode of the electrolyzer 6 is passed into the first gas-liquid separator 11 through the fifth passage, and the gas produced by the cathode of the electrolyzer 6 is passed into the second gas-liquid separator 8 through the third passage;

[0036] After the test of producing hydrogen by electrolysis of water is completed, the third passage remains closed, the fourth passage remains open, and the liquid at the cathode of the electrolytic cell 6 flows back to the water storage tank 1 through the fourth passage.

[0037] Furthermore, before the test of hydrogen production by electrolysis of water is conducted, the first passage is kept closed and the second passage is kept open, so that the liquid in the water storage tank 1 passes through the purification column 2, the conductivity tester 3, and the circulation pump 4 in sequence, and then enters the first gas-liquid separator 11 and finally flows back to the water storage tank 1. By circulating the electrolyte through the purification column 2 multiple times, the purity of the electrolyte can be improved to ensure the subsequent electrolysis effect.

[0038] The above is only a preferred implementation of the present application. 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 application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A test device for producing hydrogen by electrolysis of water, characterized in that: It comprises a water storage tank, a purification column, a conductivity tester, a circulation pump, an electrolytic cell, a first gas-liquid separator and a second gas-liquid separator, and the water storage tank, the purification column, the conductivity tester and the circulation pump are sequentially connected in series; A first passage and a second passage are respectively provided downstream of the circulation pump, wherein the first passage is used to connect the circulation pump with the anode inlet of the electrolytic cell, and the second passage is used to connect the circulation pump with the inlet of the first gas-liquid separator; the liquid outlet of the first gas-liquid separator is connected to the water storage tank; wherein a first parallel point is provided on the first passage, one end of the second passage is connected to the first parallel point, and the other end of the second passage is connected to the inlet of the first gas-liquid separator; The cathode outlet of the electrolytic cell is provided with a third passage and a fourth passage, wherein the third passage is used to connect the cathode outlet of the electrolytic cell with the inlet of the second gas-liquid separator, and the fourth passage is used to connect the cathode outlet of the electrolytic cell with the water storage tank; wherein a second parallel point is provided on the third passage, one end of the fourth passage is connected to the second parallel point, and the other end of the fourth passage is connected to the water storage tank.

2. The test device for producing hydrogen by electrolysis of water according to claim 1, characterized in that: The first passage is provided with a first valve, which is arranged between the electrolytic cell and the first parallel point; the second passage is provided with a second valve, which is located between the first parallel point and the first gas-liquid separator.

3. The testing device for producing hydrogen by electrolysis of water according to claim 1, characterized in that: The third passage is provided with a third valve, and the third valve is arranged between the electrolytic cell and the second parallel point; the fourth passage is provided with a fourth valve, and the fourth valve is located between the second parallel point in the fourth passage and the water storage tank.

4. The testing device for producing hydrogen by electrolysis of water according to claim 2, characterized in that: The first valve and the second valve are both electric valves, and the conductivity tester controls the opening and closing states of the first valve and the second valve respectively.

5. The testing device for producing hydrogen by electrolysis of water according to claim 2, characterized in that: The anode outlet of the electrolytic cell is provided with a fifth passage, one end of which is connected to the anode outlet of the electrolytic cell, and the other end of which is connected in parallel to the downstream position of the second valve in the second passage.

6. The testing device for producing hydrogen by electrolysis of water according to claim 1, characterized in that: A fluoride ion concentration monitor is provided at the inlet position of the first gas-liquid separator, and the fluoride ion concentration monitor is used to monitor the fluoride ion concentration of the liquid flowing back to the water storage tank.

7. The testing device for producing hydrogen by electrolysis of water according to claim 1, characterized in that: A first dryer is provided at the gas outlet of the first gas-liquid separator, and the first dryer is used for drying the gas separated by the first gas-liquid separator.

8. The testing device for producing hydrogen by electrolysis of water according to claim 1, characterized in that: A second dryer is provided at the gas outlet of the second gas-liquid separator, and the second dryer is used for drying the gas separated by the second gas-liquid separator.

9. A test method for producing hydrogen by electrolysis of water, which is performed using the test device according to any one of claims 1 to 8, characterized in that: At least the following steps are included: When conducting the test of hydrogen production by electrolysis of water, the first passage is kept open, the second passage is kept closed, and the liquid in the water storage tank is passed through the purification column, the conductivity tester, and the circulation pump in sequence, and then introduced into the anode inlet of the electrolytic cell; The electrolyzer is powered on and performs hydrogen production operation, at which time the third passage remains open, the fourth passage remains closed, the gas produced by the anode of the electrolyzer is passed into the first gas-liquid separator through the fifth passage, and the gas produced by the cathode of the electrolyzer is passed into the second gas-liquid separator through the third passage; After the test of hydrogen production by water electrolysis is completed, the third passage remains closed, the fourth passage remains open, and the liquid at the cathode of the electrolytic cell flows back to the water storage tank through the fourth passage.

10. The test method for producing hydrogen by electrolysis of water according to claim 9, characterized in that: Before conducting the water electrolysis hydrogen production test, keep the first passage closed and the second passage open, so that the liquid in the water storage tank passes through the purification column, conductivity tester, and circulation pump in sequence, enters the first gas-liquid separator and finally flows back to the water storage tank.

Images