A wide range stable dynamic performance test system and operation method for alkaline electrolytic cell

Abstract

The present application discloses a wide range stable dynamic performance test system and operation method of an alkaline electrolyzer, comprising an alkaline electrolyzer to be tested and a power supply system, wherein the alkaline electrolyzer to be tested is connected to a buffer unit, and the buffer unit is connected to a pure water source; the test system also comprises a hydrogen separator and an oxygen separator, wherein the hydrogen separator is connected to the hydrogen-alkali outlet end of the alkaline electrolyzer to be tested, and the liquid phase outlet of the hydrogen separator is connected to the buffer unit through a first reflux pipe; the oxygen separator is connected to the oxygen-alkali outlet end of the alkaline electrolyzer to be tested, and the liquid phase outlet of the oxygen separator is connected to the buffer unit through a second reflux pipe; when the system is started, a system self-check and state reset are first performed, and then an operation environment of the alkaline electrolyzer is constructed, and after power-on and load production of hydrogen, the system is stopped after cooling and multiple pressure relief; the present application can effectively avoid the interference of multiple factors such as temperature, liquid level and pressure on the performance detection of the alkaline electrolyzer, and meet the testing requirements of the alkaline electrolyzer under multiple working conditions.

Description

Technical Field

[0001] The present application relates to the technical field of electrolytic cell testing, and in particular to a wide range stable dynamic performance testing system and an operating method of an alkaline electrolytic cell. Background Art

[0002] As a clean energy, hydrogen has a wide range of application prospects. In the existing technology, the electrolysis of water to produce green hydrogen is the development trend of the industry. The electrolysis process of hydrogen production consumes a lot of electricity. At the same time, based on the actual needs of environmental protection, using photovoltaic, wind power and other electricity as electricity for hydrogen production has become one of the main development directions of the hydrogen production industry.

[0003] However, photovoltaic and wind power production processes are affected by the weather, resulting in greater volatility and randomness, which results in the operation mode of electrolytic hydrogen production equipment changing from stable operation to long-term wide power range fluctuation operation; in addition, with the expansion of the scale of electrolytic hydrogen production, the design of the entire electrolytic hydrogen production system has gradually shifted towards large-scale, intensive, standardized and safe operation, and equipment suppliers of electrolytic hydrogen production systems are also gradually focusing on the supply of a certain category of equipment. Therefore, a large number of key performance parameters are needed to provide data support for the design of engineering designers, but the existing technology lacks corresponding detection equipment, especially detection equipment for alkaline electrolyzers. Summary of the invention

[0004] The main purpose of the present application is to provide a wide range stable dynamic performance test system and operation method for an alkaline electrolytic cell, aiming to solve the defect of the alkaline electrolytic cell lacking a detection device in the prior art.

[0005] This application achieves the above objectives through the following technical solutions:

[0006] A wide range stable dynamic performance test system for an alkaline electrolytic cell, comprising an alkaline electrolytic cell to be tested;

[0007] A buffer unit, wherein the inlet end of the buffer unit is connected to a pure water source, and the outlet end of the buffer unit is connected to an alkaline electrolytic cell to be tested, and supplies an alkali solution for electrolysis to the alkaline electrolytic cell to be tested;

[0008] A temperature control unit, the temperature control unit is connected to the buffer unit, and the temperature control unit is used to control the temperature of the electrolysis alkali solution;

[0009] A hydrogen separator, the hydrogen separator is connected to the hydrogen and alkali outlet of the alkaline electrolytic cell to be detected, and the hydrogen separator is connected to the buffer unit through a first reflux pipe;

[0010] An oxygen separator, the oxygen separator is connected to the oxygen-alkali outlet of the alkaline electrolytic cell to be detected; the oxygen separator is connected to the buffer unit through a second reflux pipe;

[0011] An accident handling unit, wherein the gas phase outlets of the hydrogen separator and the oxygen separator are connected.

[0012] Optionally, the buffer unit includes a buffer tank, the water inlet of the buffer tank is connected to a pure water source, the outlet of the buffer tank is connected to the alkaline electrolytic cell to be tested through a circulation pump, and the buffer tank is respectively connected to the first reflux pipe and the second reflux pipe.

[0013] Optionally, the temperature control unit includes a pure water heater, a heating and cooling device and an alkali liquid cooler, the pure water heater is arranged at the pure water inlet end of the buffer tank, the heating and cooling device is arranged in the buffer tank, and the alkali liquid cooler is arranged at the liquid phase inlet end of the alkali liquid electrolytic cell to be tested.

[0014] Optionally, the gas phase outlet of the hydrogen separator is connected to a hydrogen exhaust pipe, the gas phase outlet of the oxygen separator is connected to an oxygen exhaust pipe, the hydrogen exhaust pipe is connected to a hydrogen cooler and a hydrogen flowmeter; and flame arresters are provided on both the hydrogen exhaust pipe and the oxygen exhaust pipe.

[0015] Optionally, the accident handling unit includes an accident tank, a first accident separator and a second accident separator, the accident tank is connected to the gas phase outlet end of the hydrogen separator through the first accident separator, and the accident tank is connected to the gas phase outlet end of the oxygen separator through the second accident separator.

[0016] Optionally, the test system further comprises a nitrogen filling pipe connected to a nitrogen source, wherein an outlet end of the nitrogen filling pipe is respectively connected to the liquid phase and gas phase spaces of the hydrogen separator, the oxygen separator, the emergency tank and the buffer tank.

[0017] Correspondingly, the present application also discloses an operation method of a wide range stable dynamic performance test system based on the above alkaline electrolytic cell, comprising the following steps:

[0018] Adjusting the pressure, alkali solution temperature, alkali solution flow rate and alkali solution level of the test system to construct a hydrogen production operating environment for the alkaline electrolyzer to be tested;

[0019] Applying electricity to the alkaline electrolytic cell to be tested to produce hydrogen;

[0020] Cut off the current and pure water source, and turn off the pure water heater;

[0021] The test system is cooled down and the voltage is reduced several times until the test system status is reset.

[0022] Optionally, the construction of the hydrogen production operating environment of the alkaline electrolyzer to be tested includes the following steps:

[0023] The adjustment pressure value P2 of the buffer tank is set according to the initial pressure P1 in the oxygen separator and the hydrogen separator, and the adjustment pressure value P2 satisfies P2 <P1;

[0024] Adjusting the pressure value of the buffer tank to an adjusted pressure value P2;

[0025] Adjusting the alkali liquid levels of the hydrogen separator, the oxygen separator and the buffer tank to set values;

[0026] Start the pure water heater and the heating and cooling device to adjust the temperature of the alkali solution in the buffer tank to the electrolysis temperature;

[0027] Start the power supply system to supply power to the alkaline electrolytic cell to be tested.

[0028] Optionally, the electrical loading and pressure control on the alkaline electrolytic cell to be tested includes the following steps:

[0029] Retrieve the current load matching table;

[0030] Determine the temperature of the oxygen alkali outlet end and the hydrogen alkali outlet end of the alkali solution electrolyzer to be tested;

[0031] According to the current load matching table and the temperatures of the oxygen-alkali outlet and the hydrogen-alkali outlet of the alkaline solution electrolyzer, a matching current is input into the alkaline electrolyzer to be tested.

[0032] Optionally, the test system is cooled and depressurized several times until the system state is reset, including the following steps:

[0033] Retrieve the temperature control parameters of the cooling operation, the number of pressure reduction operations, and the pressure control parameters of each pressure reduction operation;

[0034] Lowering the temperature of the alkaline solution electrolyzer to be tested according to the temperature control parameters, and performing a first pressure relief operation on the buffer tank, the oxygen separator and the hydrogen separator according to the pressure control parameters;

[0035] Closing the alkali solution inlet, the first reflux pipe and the second reflux pipe of the alkaline electrolytic cell to be tested; performing subsequent pressure relief operations on the buffer tank, the oxygen separator and the hydrogen separator in sequence according to the pressure control parameters;

[0036] Reset the test system to its initial state.

[0037] Compared with the prior art, this application has the following beneficial effects:

[0038] The present application includes an alkaline electrolytic cell to be tested and a power supply system which are interconnected, wherein the liquid phase inlet end of the alkaline electrolytic cell to be tested is also connected to a buffer unit, and the inlet end of the buffer unit is connected to a pure water source; the test system also includes a hydrogen separator and an oxygen separator, wherein the gas phase inlet of the hydrogen separator is connected to the hydrogen-alkali outlet end of the alkaline electrolytic cell to be tested, and the liquid phase outlet of the hydrogen separator is connected to the buffer unit through a first reflux pipe; the gas phase inlet of the oxygen separator is connected to the oxygen-alkali outlet end of the alkaline electrolytic cell to be tested, and the liquid phase outlet of the oxygen separator is connected to the buffer unit through a second reflux pipe;

[0039] When the test system described in the present application is used, the power supply system is used to supply power to the alkaline electrolytic cell to be tested, and the hydrogen-alkali mixture generated by the alkaline electrolytic cell to be tested during the electrolysis process enters the hydrogen separator from the hydrogen-alkali outlet, and the oxygen-alkali mixture described enters the oxygen separator from the oxygen-alkali outlet; the oxygen and hydrogen generated by separation are discharged and collected respectively; the alkaline solution separated and recovered in the hydrogen separator and the oxygen separator are respectively refluxed to the buffer unit through the first reflux pipe and the second reflux pipe; and the alkaline solution for electrolysis is supplemented into the alkaline electrolytic cell to be tested through the buffer unit;

[0040] In the prior art, the reference basis for whether to perform the water replenishment operation is the average value of the liquid levels of the oxygen separator and the hydrogen separator, that is, when the liquid level is lower than the set threshold, the water replenishment operation is started, and the water replenishment is stopped after reaching the threshold; after the water replenishment, the alkali liquid stored in the oxygen separator and the hydrogen separator will flow into the alkaline electrolytic cell after merging through the U-shaped tube at the bottom;

[0041] When the above water replenishment operation is adopted, the consumption of pure water during the electrolysis process and the one-time entry of a large amount of pure water into the oxygen separator and the hydrogen separator will cause a large fluctuation in the concentration of the alkali solution in the local area, thereby affecting the concentration of the alkali solution in the alkaline electrolytic cell;

[0042] Secondly, the pure water added is generally at room temperature, which will cause the temperature of the alkali solution to change, thereby affecting the pressure in the alkaline electrolytic cell; the large fluctuations in the concentration, temperature and internal pressure of the alkali solution electrolytic cell will seriously destroy the internal steady state of the alkaline electrolytic cell, causing the electrolytic cell to face interference from multiple parameters during the test process, making it difficult to meet the test requirements of the alkaline electrolytic cell;

[0043] Compared with the prior art, in the water replenishment process of the present application, pure water will continuously enter the buffer tank and enter the alkaline electrolytic cell after corresponding treatment. At the same time, the temperature of the alkali solution is controlled by the temperature control unit. Since the buffer tank has a large volume, it can better balance the temperature difference between the alkali solution and the pure water. Therefore, the present application realizes effective control of the concentration and temperature of the alkali solution. In addition, the flow rate of pure water is automatically adjusted according to the electrolysis current, which fundamentally avoids large fluctuations in the concentration, temperature and internal pressure of the alkali solution of the electrolytic cell, thereby ensuring the stability of the environment in the alkaline electrolytic cell and avoiding multiple parameters from interfering with the detection process.

[0044] At the same time, since regulating valves are provided on the alkali liquid reflux pipelines of the hydrogen separator and the oxygen separator, the two separators are not interconnected, the alkali liquid needs to be buffered by the buffer tank before entering the electrolytic cell, and the ports for hydrogen alkali and oxygen alkali to enter the separator at the rear end of the cell are located above the liquid level of the separator. Therefore, the liquid level difference between the oxygen separator and the hydrogen separator has a negligible effect on the pressure difference between the anode and cathode of the alkaline electrolytic cell, making the factors of environmental changes in the alkaline electrolytic cell simpler, and the control difficulty is effectively reduced. The entire test system can operate under more working conditions and meet the detection requirements of multiple working conditions.

[0045] The present application also discloses an operating method of the above-mentioned test system, which includes system self-check and initialization, alkaline electrolytic cell operating environment construction, power-on loading and parking control; wherein during the parking control process, it is necessary to perform several pressure relief operations to avoid pressure and liquid level imbalance after parking, achieve smooth parking of the entire test system, and avoid safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 A schematic diagram of the structure of a wide range stable dynamic performance test system for an alkaline electrolytic cell provided in Embodiment 1 of the present application;

[0047] Figure 2 A flow chart of an operation method of a wide range stable dynamic performance test system for an alkaline electrolytic cell provided in Embodiment 2 of the present application;

[0048] Figure numerals: 1-alkaline electrolytic cell to be tested, 2-hydrogen separator, 3-first reflux pipe, 4-oxygen separator, 5-second reflux pipe, 6-buffer tank, 7-circulation pump, 8-pure water heater, 9-heating and cooling device, 10-alkali solution cooler, 11-hydrogen exhaust pipe, 12-oxygen exhaust pipe, 13-hydrogen cooler, 14-hydrogen flowmeter, 15-flame arrester, 16-accident tank, 17-first accident separator, 18-second accident separator, 19-nitrogen filling pipe, 20-oxygen in hydrogen analyzer, 21-hydrogen in oxygen analyzer, 22-hydrogen-alkali delivery pipe, 23-alkali solution reflux pipe, 24-accident pump, 25-regulating valve, 26-power supply system, 27-oxygen-alkali delivery pipe.

[0049] The purpose, features and advantages of this application will be further described in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiment 1 is only a part of the embodiments of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0052] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0054] Implementation Method 1

[0055] Reference Figure 1 This embodiment is an optional embodiment of the present application, which discloses a wide range stable dynamic performance test system of an alkaline electrolytic cell, including an alkaline electrolytic cell 1 to be tested and a power supply system 26, wherein the power supply system 26 includes a rectifier cabinet and a corresponding control unit, which are both prior arts, and the alternating current is rectified into direct current through the rectifier cabinet, and the positive and negative poles of the rectifier cabinet are respectively connected to the anode and cathode of the alkaline electrolytic cell 1 to be tested;

[0056] The test system further includes a buffer unit, which includes a buffer tank 6, and the buffer tank 6 is provided with a liquid phase inlet end and a liquid phase outlet end. The liquid phase inlet end of the buffer tank 6 is connected to an external pure water source through a water delivery pipe, so as to achieve pure water replenishment. The water delivery pipe is provided with a flow meter to monitor the input amount of pure water in real time; the liquid phase outlet end of the buffer tank 6 is connected to the liquid phase inlet end of the alkaline electrolytic cell 1 to be tested through a circulation pump 7; the above-mentioned pure water and alkali solution delivery pipelines are both provided with regulating valves 25;

[0057] The hydrogen and alkali outlet end of the alkaline electrolytic cell 1 to be tested is connected to the hydrogen separator 2 through the hydrogen and alkali delivery pipe 22, and the oxygen and alkali outlet end of the alkaline electrolytic cell 1 to be tested is connected to the oxygen separator 4 through the oxygen and alkali delivery pipe 27; the bottom of the oxygen separator 4 and the hydrogen separator 2 is provided with a liquid phase outlet end, the liquid phase outlet end of the hydrogen separator 2 is connected to the buffer tank 6 through the first reflux pipe 3, and the liquid phase outlet end of the oxygen separator 4 is connected to the buffer tank 6 through the second reflux pipe 5, and the first reflux pipe 3 and the second reflux pipe 5 are both provided with a regulating valve 25; at the same time, the hydrogen and alkali delivery pipe 22 and the oxygen and alkali delivery pipe 27 are both provided with a pressure gauge and a pressure difference detector;

[0058] The test system further includes a temperature control unit, which includes a pure water heater 8, a heating and cooling device 9, and an alkali solution cooler 10, wherein the pure water heater 8 is arranged at the liquid phase inlet end of the buffer tank 6, and the pure water at room temperature is preheated by the pure water heater 8, thereby reducing the temperature difference between the pure water and the alkali solution in the buffer tank 6;

[0059] The heating and cooling device 9 is arranged in the buffer tank 6. When the temperature of the alkali solution in the buffer tank 6 is low, the heating and cooling device 9 heats the alkali solution, and performs cooling operation when the temperature is high;

[0060] The alkali liquid cooler 10 is arranged between the buffer tank 6 and the alkaline electrolytic cell 1 to be detected. The alkali liquid cooler 10 can be arranged at the outlet end of the circulation pump 7 or at its inlet end, wherein the outlet end of the circulation pump 7 is preferred, so that the alkali liquid entering the alkaline electrolytic cell 1 to be detected can be cooled by the alkali liquid cooler 10; at the same time, the temperature control unit also includes a plurality of temperature sensors;

[0061] During the operation of the above-mentioned test system, the supplemented pure water enters the buffer tank 6, and then enters the alkaline electrolytic cell 1 to be tested through the circulation pump 7 as needed; during the pure water input process, the regulating valve 25 and the flow meter can be used to achieve a stable and continuous input of pure water, and the input amount of pure water can be adjusted as needed to meet different water replenishment requirements under different power conditions, that is, to ensure that the amount of water in the buffer tank 6 is in a dynamic equilibrium state, thereby alleviating the fluctuation of the alkali solution concentration in the buffer tank 6 and meeting the operation requirements of the alkaline electrolytic cell;

[0062] Since in the technical solution described in the present application, the reflux pipelines of the oxygen separator 4 and the hydrogen separator 2 are directly connected to the buffer tank 6, that is, the alkaline solution generated during the gas separation process will directly flow back into the buffer tube, so during the working process, the oxygen separator 4 and the hydrogen separator 2 only affect the alkaline electrolytic cell through their internal pressures, and the liquid levels in the oxygen separator 4 and the hydrogen separator 2 will not affect the alkaline electrolytic cell. The working conditions of the alkaline electrolytic cell are simpler, and the control difficulty is effectively reduced. Therefore, the entire test system can realize detection under more working conditions and meet the detection requirements of multiple working conditions;

[0063] The temperature control unit can control the temperature of the alkali solution in the buffer tank 6 and the alkaline electrolytic cell 1 to be detected, so as to avoid the temperature change affecting the operation of the alkaline electrolytic cell 1 to be detected, thereby avoiding the interference of temperature on the detection data and improving the detection accuracy;

[0064] Secondly, the temperature control unit described in the present application performs multi-faceted control from the pure water inlet end, temporary storage end and final output end, which can not only improve the control accuracy, but also significantly improve the response speed of temperature control and the smoothness of control, meet the high-precision temperature control requirements during detection, and meet the needs of detection.

[0065] In addition, since the oxygen separator 4 is isolated from the hydrogen separator 2, in actual operation, the pressure at one end of the hydrogen separator 2 or the oxygen separator 4 can be used as a reference, and the valve at the other end can be adjusted according to the corresponding pressure difference value, thereby realizing the follow-up control of the pressure on the hydrogen side and the oxygen side, ensuring the pressure balance between the positive and negative stages of the alkaline electrolyzer, reducing the possibility of accidents such as hydrogen and oxygen permeation and diaphragm cross-gas, and improving the safety of the operation of the entire device;

[0066] When the external power source is wind power or photovoltaic power, the operating power of the alkaline electrolyzer will fluctuate widely, which will cause fluctuations in the production of hydrogen and oxygen, and further affect the drastic changes in the pressure in the oxygen generator and the hydrogen generator. Based on the above-mentioned pressure control method, the test system described in the present application can ensure the balance of pressure at the oxygen end and the hydrogen end, thereby meeting the detection requirements under conditions of wide power fluctuations, further expanding the scope of application of the equipment.

[0067] The gas phase outlet end of the hydrogen separator 2 is provided with an oxygen-in-hydrogen analyzer 20, and the gas phase outlet end of the oxygen separator 4 is provided with an oxygen-in-hydrogen analyzer 21. The oxygen-in-hydrogen analyzer 20 and the hydrogen-in-oxygen analyzer 21 are arranged at the gas outlet ends of the corresponding gas separators, so that the impurity content in oxygen and hydrogen can be obtained at the first time, thereby improving the timeliness of the data, avoiding the detection error caused by long-distance pipeline transportation, and improving the accuracy of the data;

[0068] At the same time, in order to further improve the timeliness and accuracy of the data, the hydrogen-oxygen analyzer 20 and the oxygen-hydrogen analyzer 21 can also be respectively arranged at the hydrogen-alkali outlet and the oxygen-alkali outlet of the alkaline electrolyzer;

[0069] An oxygen exhaust pipe 12 is provided at the gas phase outlet end of the oxygen separator 4, and a hydrogen exhaust pipe 11 is provided at the gas phase outlet end of the hydrogen separator 2. A flame arrester 15 and a corresponding regulating valve 25 are provided on the oxygen exhaust pipe 12 as a secondary valve, and a hydrogen cooler 13 and a hydrogen flowmeter 14 are provided on the hydrogen exhaust pipe 11. Meanwhile, a corresponding regulating valve 25 is also provided on the hydrogen exhaust pipe 11 as a secondary valve;

[0070] The above arrangement can realize rapid evacuation or discharge collection of oxygen under controllable pressure, and can also rapidly cool the hydrogen at the separation point through the hydrogen cooler 13, thereby controlling the temperature of the hydrogen and avoiding safety accidents;

[0071] At the same time, compared with the prior art, the present application is provided with a regulating valve 25 as a secondary valve on both the oxygen exhaust pipe 12 and the hydrogen exhaust pipe 11, which can effectively control the flow rate of the hydrogen and oxygen outlet ends, thereby ensuring the safety during the test; on the other hand, it can simulate various back pressure conditions at the rear end by controlling the opening and closing degree of the regulating valve 25, enriching the test scenarios while improving the measurement accuracy of the hydrogen flow meter;

[0072] The test system also includes an accident handling unit, which includes an accident tank 16, a first accident separator 17 and a second accident separator 18. The hydrogen exhaust pipe 11 is connected to the first accident separator 17 through a parallel branch, and the oxygen exhaust pipe 12 is connected to the second accident separator 18 through a parallel branch. The liquid phase outlet end of the first accident separator 17 is connected to the accident tank 16, and the liquid phase outlet of the second accident separator 18 is connected to the accident tank 16. The hydrogen exhaust pipe 11, the oxygen exhaust pipe 12 and their respective connecting branches are provided with regulating valves 25 to control the on-off state of each pipeline, and ensure that the airflow pipeline is switched through the regulating valve 25 only in the event of a production accident, thereby activating the accident tank 16, the first accident separator 17 and the second accident separator 18.

[0073] A alkali solution reflux pipe 23 is provided at the bottom of the accident tank 16, and a corresponding accident pump 24 and a regulating valve 25 are also provided on the alkali solution reflux pipe 23. After the accident is handled, the accident pump 24 guides the accumulated alkali solution in the accident tank 16 to flow back into the buffer tank 6, so as to realize the reuse of the alkali solution.

[0074] When the external power source is wind power, photovoltaic power or other power sources, the power of the alkaline electrolyzer will change dramatically, causing rapid changes in the production of hydrogen and oxygen, and then causing large fluctuations in the pressure in the oxygen separator 4 and the hydrogen separator 2, thereby causing an alkali spraying accident. The above-mentioned device described in the present application can timely introduce the mixture of alkali liquid and gas sprayed in the alkali spraying accident into the corresponding accident separator, and perform secondary separation of the above-mentioned mixture of alkali liquid and gas through the corresponding accident separator, thereby achieving rapid pressure relief of the oxygen separator 4 and the hydrogen separator 2, ensuring the safe operation of the equipment while also enabling the reuse of the alkali liquid; greatly improving the safety and stability of the operation of the entire device.

[0075] The test system also includes a nitrogen filling tube 19, the inlet ends of the nitrogen filling tube 19 are respectively connected to a nitrogen source, and the outlet end of the nitrogen filling tube 19 is provided with 4 branches, and each branch is also provided with a gas phase outlet end and a liquid phase outlet end, and the above 4 branches are respectively connected to the buffer tank 6, the oxygen separator 4, the hydrogen separator 2 and the accident tank 16; each of the gas phase outlet ends is respectively connected to the gas phase space at the upper part of the buffer tank 6, the oxygen separator 4, the hydrogen separator 2 and the accident tank 16, and each of the liquid phase outlet ends is respectively connected to the liquid phase space at the lower part of the buffer tank 6, the oxygen separator 4, the hydrogen separator 2 and the accident tank 16;

[0076] The nitrogen filling pipe 19 can be used to timely fill nitrogen into the system when the hydrogen and oxygen impurity content exceeds the standard, so that the sensitive medium can be discharged from the test system after diluting the impurities, ensuring the safe operation of the system;

[0077] When a minor accident such as level 1 or level 2 occurs, nitrogen can be injected into the gas phase space of the accident equipment through the gas phase outlet to remove the sensitive medium. When a serious accident of level 3 or above occurs, nitrogen can be directly injected into the liquid phase space of the accident equipment through the liquid phase outlet to remove the sensitive medium. Different disposal plans can be matched for accidents of different levels, which not only has a higher safety factor, but also can save nitrogen and reduce the operating cost of the test system.

[0078] It should also be noted that when nitrogen is charged through the liquid phase outlet, nitrogen can also be charged through the gas phase outlet simultaneously.

[0079] Implementation Method 2

[0080] This embodiment, as another optional embodiment of the present application, discloses an operation method of a wide range stable dynamic performance test system of an alkaline electrolytic cell, comprising the following steps:

[0081] S1, test system self-check and initialization;

[0082] Start the test system through the upper control machine or industrial control cabinet, and check whether there is an interlock or equipment fault signal in the current state of the test system. If so, reset and restart the test system after eliminating the interlock and fault;

[0083] Set the circulation pump, temperature control unit, current system, regulating valves and other components to their initial default state, and start auxiliary equipment such as cooling water pump and demineralized water;

[0084] The above operations can effectively ensure that each link is in a suitable working state, thereby improving the safety of the test system.

[0085] S2. Adjust the pressure, lye temperature, lye flow rate, and lye liquid level of the test system to construct the hydrogen production operating environment for the alkaline electrolyzer to be detected;

[0086] S21. Set the adjusted pressure value P2 of the buffer tank according to the initial pressure P1 of the oxygen separator and the hydrogen separator, and the adjusted pressure value P2 satisfies P2 < P1;

[0087] In the initial state of the test system, the initial pressures in the buffer tank, the oxygen separator, and the hydrogen separator are the same, and their values are all P1; it should be noted that the specific value of P1 is determined according to the actual working conditions;

[0088] Set the adjusted pressure value P2 of the buffer tank as needed, and the adjusted pressure value P2 satisfies P2 < P1. As for the difference between the adjusted pressure value P2 and the initial pressure P1, the staff determines it according to the actual situation. At the same time, the rate of pressure reduction is also determined by the staff according to the actual situation to ensure the safety of debugging;

[0089] S22. Adjust the pressure value of the buffer tank to the adjusted pressure value P2;

[0090] Open the gas phase outlet end of the buffer tank, reduce the pressure in the buffer tank by exhausting the excess gas, and observe the pressure in the buffer tank through the pressure gauge of the buffer tank until the pressure in the buffer tank reaches the adjusted pressure value P2;

[0091] In the test system described in the present application, the oxygen separator and the hydrogen separator are in a separated state. Therefore, in order to ensure the flow of the lye, it is necessary to make the pressure in the buffer tank lower than the pressures of the oxygen separator and the hydrogen separator, forming a pressure difference between the buffer tank and the oxygen separator and the hydrogen separator, so as to ensure that the lye in the oxygen separator and the hydrogen separator can flow back into the buffer tank, thereby ensuring the effectiveness of liquid level control and performing related actions for liquid level control;

[0092] S23. Adjust the lye liquid levels of the hydrogen separator, the oxygen separator, and the buffer tank to the set values;

[0093] After the pressure in the buffer tank reaches the adjusted pressure value P2, open the regulating valves on the pure water inlet end of the buffer tank and the lye inlet end of the lye electrolyzer, control the pure water to enter the buffer tank, and at the same time transport the lye into the alkaline electrolyzer through the circulation pump;

[0094] The input amount of the pure water and the reflux amount of the alkali solution are controlled by controlling the opening sizes of the regulating valves on the water delivery pipe, the first reflux pipe and the second reflux pipe, and the rotation speed of the circulating pump is controlled at the same time, so as to achieve a dynamic balance between the pure water flow, the alkali solution flow and the reflux alkali solution flow, and ensure that the alkali solution levels in the alkali solution buffer tank, the hydrogen and oxygen separators are maintained at their respective set values ​​on the basis of meeting the water consumption of electrolysis;

[0095] Then the alkali liquid level in the alkaline electrolytic cell is adjusted until the alkali liquid level in the alkaline electrolytic cell reaches a set value;

[0096] S24, start the pure water heater and the heating and cooling device to adjust the temperature of the alkali solution in the buffer tank to the electrolysis temperature;

[0097] The pure water heater and the heating and cooling device are turned on to heat the pure water and the alkali solution in the buffer tank. At the same time, the pure water temperature at the inlet end of the buffer tank and the alkali solution temperature at the inlet end of the alkaline electrolytic cell to be detected are detected in real time through the corresponding temperature detection device until the alkali solution temperature at the inlet end of the alkaline electrolytic cell to be detected reaches the electrolysis temperature of the alkaline electrolytic cell.

[0098] S25. Start the power supply system to supply power to the alkaline electrolytic cell.

[0099] The power supply system includes a rectifier cabinet and related auxiliary control equipment, and supplies power to the alkaline electrolyzer by starting the rectifier cabinet.

[0100] S3, applying electricity to the alkaline electrolytic cell to be tested to produce hydrogen;

[0101] S31, retrieve the current load matching table;

[0102] Corresponding temperature sensors are provided at both the oxygen-alkali outlet and the hydrogen-alkali outlet of the alkaline electrolyzer, and the temperatures of the corresponding outlets are detected by the temperature sensors. The temperature measurement value in the current load matching table is the average value of the temperatures of the oxygen-alkali outlet and the hydrogen-alkali outlet;

[0103] It should also be pointed out that, in addition to adjusting the power-on load according to the current load matching table, dynamic corresponding load can also be performed, that is, a follow-up change curve between pressure, flow and current is established through computer fitting, so as to realize the dynamic corresponding load of current according to the above follow-up change curve;

[0104] The various parameters in the current load matching table are set according to actual needs. The following table lists the current load matching table as an example:

[0105]

[0106] It should be noted that the relevant parameters in the above table can be flexibly adjusted according to actual working conditions and needs;

[0107] S32, measuring the temperatures of the oxygen alkali outlet end and the hydrogen alkali outlet end of the alkali solution electrolyzer to be tested;

[0108] Detecting the temperatures of the oxygen alkali outlet and the hydrogen alkali outlet of the alkali solution electrolyzer by a temperature sensor, and calculating the average values ​​of the above temperatures;

[0109] S33, inputting a matching current into the alkaline electrolytic cell according to the current load matching table and the temperatures of the oxygen-alkali outlet and the hydrogen-alkali outlet of the alkaline solution electrolytic cell.

[0110] The corresponding current parameter is read according to the temperature value calculated in step S32, and current loading is performed.

[0111] S4, cut off the current and pure water source, and turn off the pure water heater;

[0112] After the test is completed, when the entire test system needs to be shut down, first issue a shutdown command to the rectifier cabinet in the power supply system to cut off the power supply of the alkaline electrolyzer. The current of the alkaline electrolyzer is reduced to 0 at a certain rate. The rate of current reduction needs to be determined by the staff according to the actual situation.

[0113] When the current of the alkaline electrolytic cell is detected to be 0, the regulating valve on the pure water source is closed to cut off the pure water source, and the pure water heater is turned off at the same time, thereby cutting off the water supply pipeline of the test system;

[0114] S5. Perform cooling and pressure reduction operations on the test system several times until the test system status is reset.

[0115] S51, retrieve the temperature control parameters of the cooling operation, the number of pressure reduction operations, and the pressure control parameters of each pressure reduction operation;

[0116] Take the current buffer tank temperature as the initial value, set the target temperature value after cooling according to the process requirements, and set the cooling speed according to the process conditions, initial setting value and target temperature value; for example, if the initial value is 75℃, the target temperature value is 50℃, and the cooling speed is set to 1℃ / min;

[0117] The current pressure in the hydrogen separator and the oxygen separator is used as the initial setting value, and the number of pressure reductions and the target pressure value of each pressure reduction are set according to the process conditions, and the pressure reduction rate of each pressure reduction is set; wherein the number of pressure reductions is preferably 2-3 times;

[0118] If the following pressure control parameters are set, after the first pressure relief, the target pressure value of the oxygen separator is 1.0MPa, the target pressure value of the hydrogen separator is 0.8MPa, and the pressure relief rate of the first pressure relief is 40kPa / s;

[0119] After the second pressure relief, the target pressure value of the oxygen separator is 0.5MPa, and the target pressure value of the hydrogen separator is 0.3MPa. At the same time, the pressure relief rate of the second pressure relief is 40kPa / s;

[0120] The above parameters need to be determined by the staff in advance according to the working conditions and then entered into the control system. After the corresponding process is carried out, the control system can call up the corresponding parameters;

[0121] S52, lowering the temperature of the alkali solution electrolyzer according to the temperature control parameter, and performing a first pressure relief operation on the buffer tank, the oxygen separator and the hydrogen separator according to the pressure control parameter;

[0122] The temperature of the alkali solution is lowered by the heating and cooling device in the buffer tube and the alkali solution cooler, and the temperature in the alkali solution electrolytic cell is gradually lowered by the flow of the alkali solution until the temperature reaches the target temperature value;

[0123] While cooling the alkali liquid electrolyzer, the exhaust pipelines and regulating valves on the oxygen separator and the hydrogen separator are opened synchronously, so as to adjust the pressures in the oxygen separator and the hydrogen separator, until the pressures in the oxygen separator and the hydrogen separator reach their respective target pressure values, and at the same time, the relevant exhaust regulating valves are closed;

[0124] S53, closing the alkali solution inlet, the first reflux pipe and the second reflux pipe of the alkaline electrolytic cell; performing subsequent pressure relief operations on the buffer tank, the oxygen separator and the hydrogen separator in sequence according to the pressure control parameters;

[0125] After the first pressure relief operation is completed, the regulating valves on the alkali solution inlet end of the alkaline electrolytic cell, the first reflux pipe and the second reflux pipe are closed, thereby isolating the buffer tank, the alkaline electrolytic cell, the oxygen separator and the hydrogen separator from each other;

[0126] According to the relevant pressure control parameters of the secondary pressure relief, the exhaust regulating valves on the oxygen separator and the hydrogen separator are opened again to perform pressure relief operations on the oxygen separator and the hydrogen separator until the pressures in the oxygen separator and the hydrogen separator reach their respective target pressure values, and at the same time, the relevant exhaust regulating valves are closed;

[0127] During the cooling and pressure relief process, the changes caused by pressure relief are much faster than those caused by cooling and liquid level control. Therefore, if only one pressure relief is performed, it will lead to a mismatch between cooling, pressure relief and liquid level control, thus causing safety hazards.

[0128] In the cooling and pressure relief process of the present application, the pressure relief operation is set up at least twice. While achieving orderly and staged pressure reduction, the temperature, pressure and flow are kept in a dynamic equilibrium state, thereby ensuring the stability of the environment within the entire system.

[0129] S54, resetting the state of the test system.

[0130] After the pressure relief operation is completed, the staff needs to recheck whether each regulating valve, circulation pump, temperature control unit and power supply system are in the reset state. If not, perform corresponding adjustment operations.

[0131] The operating method described in the present application can flexibly and safely construct a wide range of operating test conditions for the electrolytic cell in the entire test system, effectively reduce the interference of factors such as alkali solution temperature, alkali solution concentration, and pressure during the test, and improve the accuracy of detection.

[0132] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A wide range stable and dynamic performance test system for an alkaline electrolytic cell, characterized in that: It comprises an alkaline electrolytic cell (1) to be tested; A buffer unit, wherein the inlet end of the buffer unit is connected to a pure water source, the outlet end of the buffer unit is connected to an alkaline electrolytic cell (1) to be detected, and an alkali solution for electrolysis is supplied to the alkaline electrolytic cell (1) to be detected; the buffer unit comprises a buffer tank (6), the water inlet of the buffer tank (6) is connected to the pure water source, the outlet end of the buffer tank (6) is connected to the alkaline electrolytic cell (1) to be detected via a circulation pump (7), and the buffer tank (6) is respectively connected to a first reflux pipe (3) and a second reflux pipe (5); A temperature control unit, the temperature control unit is connected to the buffer unit, and the temperature control unit is used to control the temperature of the electrolysis alkali solution; A hydrogen separator (2), the hydrogen separator (2) being connected to the hydrogen-alkali outlet of the alkaline electrolytic cell (1) to be detected, the hydrogen separator (2) being connected to the buffer unit via a first reflux pipe (3); the gas phase outlet of the hydrogen separator (2) being connected to a hydrogen exhaust pipe (11); An oxygen separator (4), the oxygen separator (4) being connected to the oxygen-alkali outlet of the alkaline electrolytic cell (1) to be detected; the oxygen separator (4) being connected to the buffer unit via a second reflux pipe (5), and the gas phase outlet of the oxygen separator (4) being connected to an oxygen exhaust pipe (12); An accident handling unit, wherein the hydrogen separator (2) and the gas phase outlet of the oxygen separator (4) are connected to each other; The accident handling unit comprises an accident tank (16), a first accident separator (17) and a second accident separator (18); the hydrogen exhaust pipe (11) is connected to the first accident separator (17) through a parallel branch; the oxygen exhaust pipe (12) is connected to the second accident separator (18) through a parallel branch; the liquid phase outlet of the first accident separator (17) is connected to the accident tank (16); the liquid phase outlet of the second accident separator (18) is connected to the accident tank (16); regulating valves (25) are provided on the hydrogen exhaust pipe (11), the oxygen exhaust pipe (12) and their respective connecting branches to control the on-off state of each pipeline, and ensure that the airflow pipeline is switched through the regulating valve (25) only when a production accident occurs, thereby activating the accident tank (16), the first accident separator (17) and the second accident separator (18); A alkali solution reflux pipe (23) is arranged at the bottom of the accident tank (16), and a corresponding accident pump (24) and a regulating valve (25) are also arranged on the alkali solution reflux pipe (23). After the accident is handled, the accident pump (24) guides the accumulated alkali solution in the accident tank (16) to flow back into the buffer tank (6), thereby realizing the reuse of the alkali solution.

2. The wide range stable and dynamic performance test system of an alkaline electrolytic cell according to claim 1, characterized in that: The temperature control unit comprises a pure water heater (8), a heating and cooling device (9) and an alkaline solution cooler (10); the pure water heater (8) is arranged at the pure water inlet end of the buffer tank (6); the heating and cooling device (9) is arranged in the buffer tank (6); and the alkaline solution cooler (10) is arranged at the liquid phase inlet end of the alkaline electrolytic cell (1) to be detected.

3. The wide range stable and dynamic performance test system of an alkaline electrolytic cell according to claim 1, characterized in that: The hydrogen exhaust pipe (11) is connected to a hydrogen cooler (13) and a hydrogen flow meter (14); and flame arresters (15) are provided on both the hydrogen exhaust pipe (11) and the oxygen exhaust pipe (12).

4. The wide range stable and dynamic performance test system of an alkaline electrolytic cell according to claim 1, characterized in that: The test system further comprises a nitrogen filling pipe (19) connected to a nitrogen source, wherein an outlet end of the nitrogen filling pipe (19) is respectively connected to the liquid phase and gas phase spaces of the hydrogen separator (2), the oxygen separator (4), the emergency tank (16) and the buffer tank (6).

5. An operating method of a wide range stable and dynamic performance test system for an alkaline electrolytic cell according to any one of claims 1 to 4, characterized in that: The following steps are involved: Adjusting the pressure, alkali solution temperature, alkali solution flow rate and alkali solution level of the test system to construct a hydrogen production operating environment for the alkaline electrolyzer to be tested; Applying electricity to the alkaline electrolytic cell to be tested to produce hydrogen; Cut off the current and pure water source, and turn off the pure water heater; The test system is cooled down and the voltage is reduced several times until the test system status is reset.

6. The operating method of the wide range stable dynamic performance test system of the alkaline electrolytic cell according to claim 5, characterized in that: The step of adjusting the pressure, alkali solution temperature, alkali solution flow rate and alkali solution level of the test system to construct a hydrogen production operating environment of the alkaline electrolyzer to be tested comprises the following steps: The adjustment pressure value P2 of the buffer tank is set according to the initial pressure P1 of the oxygen separator and the hydrogen separator, and the adjustment pressure value P2 satisfies P2 <P1; Adjusting the pressure value of the buffer tank to an adjusted pressure value P2; Adjusting the alkali liquid levels of the hydrogen separator, the oxygen separator and the buffer tank to set values; Start the pure water heater and the heating and cooling device to adjust the temperature of the alkali solution in the buffer tank to the electrolysis temperature; Start the power supply system to supply power to the alkaline electrolytic cell to be tested.

7. The operating method of the wide range stable dynamic performance test system of the alkaline electrolytic cell according to claim 5, characterized in that: The step of applying power to the alkaline electrolytic cell to be tested to produce hydrogen comprises the following steps: Retrieve the current load matching table; Determine the temperature of the oxygen-alkali outlet end and the hydrogen-alkali outlet end of the alkaline electrolytic cell to be tested; According to the current load matching table and the temperatures of the oxygen-alkali outlet and the hydrogen-alkali outlet of the alkaline electrolytic cell, a matching current is input into the alkaline electrolytic cell to be tested.

8. The operating method of the wide range stable dynamic performance test system of the alkaline electrolytic cell according to claim 5, characterized in that: The test system is cooled and the voltage is reduced several times until the test system state is reset. The following steps are involved: Retrieve the temperature control parameters of the cooling operation, the number of pressure reduction operations, and the pressure control parameters of each pressure reduction operation; Lowering the temperature of the alkaline electrolytic cell to be tested according to the temperature control parameter, and performing a first pressure relief operation on the buffer tank, the oxygen separator and the hydrogen separator according to the pressure control parameter; Closing the alkali solution inlet, the first reflux pipe and the second reflux pipe of the alkaline electrolytic cell to be tested; performing subsequent pressure relief operations on the buffer tank, the oxygen separator and the hydrogen separator in sequence according to the pressure control parameters; Reset the test system status.

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