An automatic alkali replenishment method and device for the alkali liquor circulation system of a hydrogen production electrolytic cell

Abstract

The present invention discloses an automatic alkali replenishment method and device for an alkali liquor circulation system of a hydrogen production electrolytic cell. The method comprises the following steps: Step 1) According to the operation data of the alkali liquor circulation system of the hydrogen production electrolytic cell, obtain the alkali loss rate of the alkali liquor circulation system of the hydrogen production electrolytic cell at different alkali liquor circulation speeds; Step 2) Obtain the real-time alkali liquor circulation speed of the alkali liquor circulation system of the hydrogen production electrolytic cell; Step 3) Obtain the real-time alkali liquor loss rate of the alkali liquor circulation system of the hydrogen production electrolytic cell according to the alkali loss rate at different alkali liquor circulation speeds and the real-time alkali liquor circulation speed of the alkali liquor circulation system of the hydrogen production electrolytic cell; Step 4) Add replenishing alkali liquor to the alkali liquor circulation system of the hydrogen production electrolytic cell in real time according to the real-time alkali liquor loss rate. The present invention can realize the real-time automatic replenishment of the alkali liquor lost during the alkaline electrolytic water hydrogen production process, and effectively solves the problems of regular alkali liquor specific gravity testing and alkali replenishment during the hydrogen production process.

Description

Technical Field

[0001] The present invention belongs to the technical field of alkaline electrolytic water hydrogen production, and particularly relates to an automatic alkali replenishment method and device for the alkali solution circulation system of a hydrogen production electrolytic cell. Background Art

[0002] Hydrogen production by electrolyzing water is one of the main technologies for realizing clean power consumption and green hydrogen production. Alkaline electrolytic water hydrogen production has received wide attention and application due to its high technical maturity and significant price advantage. During the electrolysis process of this technology, the alkali solution stored in the alkali solution tank is injected into the electrolytic cell by an alkali solution pump. An oxidation-reduction reaction occurs in the electrolytic cell to generate hydrogen and oxygen, which are led out through the hydrogen gas path and oxygen gas path at both ends of the electrolytic cell and enter the hydrogen separator and oxygen separator respectively for gas separation. The hydrogen separated by the hydrogen separator enters the hydrogen purification device, and the alkali solution flows back to the alkali solution tank for the next cycle. The oxygen separated by the oxygen separator enters the oxygen purification device, and the alkali solution flows back to the alkali solution tank for the next cycle. During the electrolysis of water, the alkali solution plays a role in increasing conductivity and is theoretically not consumed. In fact, with the water carried out by hydrogen and oxygen, there is always a trace amount of alkali solution. After the equipment runs for a long time, the concentration of the alkali solution decreases, resulting in an increase in power consumption and the equipment being unable to operate under the rated condition. At this time, alkali solution should be replenished.

[0003] During the process of alkaline electrolytic water hydrogen production, generally the specific gravity of the alkali solution is 1.28 (30% KOH solution), and when it drops to 1.22, alkali needs to be replenished. Generally, the specific gravity is tested every 15 days to determine whether to replenish alkali. This way of frequently testing the specific gravity of the alkali solution and replenishing the alkali solution increases the difficulty and workload of the operation and maintenance of electrolytic hydrogen production. When the operation and maintenance personnel do not conduct the specific gravity test and alkali replenishment of the alkali solution in time due to certain special reasons, it will have an important impact on the hydrogen production process. At the same time, within a alkali replenishment cycle, the specific gravity of the alkali solution gradually drops from 1.28 to 1.22, and the power consumption of hydrogen production also changes periodically, affecting the overall power consumption of the hydrogen production system and further affecting the operation economy of the hydrogen production plant. If the alkali solution lost during the electrolysis of water can be automatically replenished in real time, the above problems can be solved. However, there is currently no solution for automatically replenishing the alkali solution for the alkali solution loss during the alkaline electrolytic water hydrogen production process. Summary of the Invention

[0004] The purpose of the present invention is to provide an automatic alkali replenishment method and device for the alkali solution circulation system of a hydrogen production electrolytic cell to realize the real-time automatic replenishment of the alkali solution lost during the electrolysis of water, reduce the difficulty and workload of the operation and maintenance of electrolytic hydrogen production, and eliminate the change in the power consumption of hydrogen production caused by alkali loss. The present invention adopts the following technical solutions:

[0005] An automatic alkali replenishment method for the alkali solution circulation system of a hydrogen production electrolytic cell includes the following steps:

[0006] Step 1) Obtain the alkali loss rate of the alkali liquor circulation system of the hydrogen production electrolyzer at different alkali liquor circulation speeds according to the operation data of the alkali liquor circulation system of the hydrogen production electrolyzer;

[0007] Step 2) Obtain the real-time alkali liquor circulation speed of the alkali liquor circulation system of the hydrogen production electrolyzer;

[0008] Step 3) Obtain the real-time alkali loss rate of the alkali liquor circulation system of the hydrogen production electrolyzer according to the alkali loss rate at different alkali liquor circulation speeds and the real-time alkali liquor circulation speed of the alkali liquor circulation system of the hydrogen production electrolyzer;

[0009] Step 4) Add make-up alkali liquor to the alkali liquor circulation system of the hydrogen production electrolyzer in real time according to the real-time alkali loss rate.

[0010] Optionally, the concentration of the make-up alkali liquor is: the make-up alkali liquor is a KOH solution with a mass fraction of 30% - 35%. At 30 °C, the specific gravity of a 30% KOH solution is 1.28, and the specific gravity of a 35% KOH solution is 1.33.

[0011] Optionally, the method for obtaining the real-time alkali liquor circulation flow rate of the alkali liquor circulation system of the hydrogen production electrolyzer is: obtain the real-time alkali liquor flow rate added to the hydrogen production electrolyzer in the alkali liquor circulation system of the hydrogen production electrolyzer.

[0012] Optionally, the alkali loss rates at different alkali liquor circulation speeds are all actually measured during the operation of the alkali liquor circulation system of the hydrogen production electrolyzer.

[0013] Optionally, the alkali loss rates at different alkali liquor circulation speeds are obtained by establishing a mathematical model after actually measuring part of the alkali loss rate data and fitting and calculating through the mathematical model.

[0014] Optionally, the actual measurement method is to stably operate the alkali liquor circulation system of the hydrogen production electrolyzer at an alkali liquor circulation speed for a period of time, measure the specific gravity of the alkali liquor before and after operation, and calculate the alkali loss rate at this speed through the change in specific gravity.

[0015] Based on the above method, the present invention also proposes an automatic alkali replenishing device for the alkali liquor circulation system of a hydrogen production electrolyzer, including:

[0016] A make-up alkali liquor tank for storing make-up alkali liquor;

[0017] A make-up alkali liquor pump for adding the make-up alkali liquor in the make-up alkali liquor tank to the alkali liquor circulation system of the hydrogen production electrolyzer;

[0018] A flow rate collector for obtaining the real-time alkali liquor circulation speed of the alkali liquor circulation system of the hydrogen production electrolyzer;

[0019] A data processor stores data on the alkali loss rate corresponding to different alkali liquor circulation speeds; the data processor calculates and controls the flow rate of the supplementary alkali liquor added to the alkali liquor circulation system of the hydrogen production electrolyzer by the supplementary alkali liquor pump according to the real-time alkali liquor circulation speed obtained by the flow rate collector.

[0020] Optionally, the alkali liquor circulation system of the hydrogen production electrolyzer includes an alkali liquor tank, and the alkali liquor tank is connected to the hydrogen production electrolyzer through an alkali liquor circulation pump and an alkali liquor flowmeter in sequence; the flow rate collector is installed on the alkali liquor flowmeter.

[0021] Optionally, the alkali liquor circulation system of the hydrogen production electrolyzer includes a supplementary alkali buffer tank, and the supplementary alkali buffer tank is connected to the supplementary alkali liquor pump, the hydrogen separator, the oxygen separator, and the alkali liquor tank in the alkali liquor circulation system of the hydrogen production electrolyzer;

[0022] The supplementary alkali liquor pump adds the supplementary alkali liquor into the supplementary alkali buffer tank, and the supplementary alkali liquor is mixed with the reflux alkali liquor of the hydrogen separator and the oxygen separator in the supplementary alkali buffer tank and then enters the alkali liquor tank.

[0023] Optionally, a supplementary alkali liquor flowmeter is provided between the supplementary alkali liquor pump and the supplementary alkali buffer tank.

[0024] Optionally, a stirring device is provided in the supplementary alkali buffer tank.

[0025] Optionally, the stirring device is a magnetic stirrer.

[0026] Optionally, a supplementary alkali controller is provided on the supplementary alkali liquor pump, and the data processor controls the flow rate of the supplementary alkali liquor added to the alkali liquor circulation system of the hydrogen production electrolyzer through the supplementary alkali controller.

[0027] Optionally, the supplementary alkali controller is a PLC controller or a DCS controller.

[0028] Optionally, the data processor is a PC computer.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] The present invention can realize the real-time automatic replenishment of the alkali liquor lost in the process of alkaline electrolytic water hydrogen production, effectively solves the problems of regular alkali liquor specific gravity testing and alkali replenishment in the hydrogen production process, reduces the operation and maintenance difficulty and the workload of operation and maintenance personnel; and solves the problem of periodic change of power consumption in the traditional alkali replenishment process, maintains the relative stability of hydrogen production power consumption, and effectively improves the operation economy of the hydrogen production plant. Description of the Drawings

[0031] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0032] Figure 1 is a schematic structural diagram of the prior art caustic soda solution circulation system of the electrolytic cell;

[0033] Figure 2 is a schematic structural diagram of the caustic soda solution circulation system of the electrolytic cell with an automatic caustic soda replenishing device according to the present invention. Specific Embodiments

[0034] The following embodiments are provided to better further understand the present invention, which are not limited to the best embodiments, and do not limit the content and protection scope of the present invention. Any product that is the same as or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior art features falls within the protection scope of the present invention.

[0035] For those embodiments where specific experimental steps or conditions are not indicated, the operations or conditions of the conventional experimental steps described in the literature in this field can be followed. For the reagents or instruments whose manufacturers are not indicated, they are all conventional reagent products that can be obtained through commercial purchase.

[0036] Example 1

[0037] The existing hydrogen production electrolytic cell caustic soda solution circulation system is as Figure 1 shown, including a caustic soda solution tank 1, a caustic soda solution circulation pump 2, a caustic soda solution flowmeter 3, an electrolytic cell 4, a hydrogen separator 5, a hydrogen purification device 51, an oxygen separator 6, and an oxygen purification device 61.

[0038] Its working process is as follows: The lye in the lye tank 1 is pumped out by the lye circulation pump 2, passes through the lye flowmeter 3, and is sent to the electrolyzer 4 for electrolysis. After electrolysis, the mixture of hydrogen and electrolyte comes out from the cathode of the electrolyzer and reaches the hydrogen separator 6 for gas-liquid separation. The separated hydrogen enters the hydrogen purification device 61, and the electrolyte accompanying the hydrogen flows back to the lye tank 1; the mixture of oxygen and electrolyte comes out from the anode of the electrolyzer and reaches the oxygen separator 5 for gas-liquid separation. The separated oxygen enters the oxygen purification device 51, and the electrolyte flows back to the lye tank 1, forming a cycle. However, with the moisture carried out by hydrogen and oxygen, there is always a trace amount of lye. After the equipment runs for a long time, the concentration of the lye will decrease, resulting in an increase in power consumption and the equipment cannot operate under the rated condition. At this time, lye should be replenished. During the process of alkaline electrolytic water hydrogen production, the specific gravity of the lye is 1.28 (30% KOH solution). When it drops to 1.22, lye must be replenished. Generally, the specific gravity is measured every 15 days to determine whether to replenish lye.

[0039] In order to achieve real-time automatic lye replenishment, this embodiment proposes an automatic lye replenishment method for the lye circulation system of a hydrogen production electrolyzer, including the following steps:

[0040] Step 1) According to the operation data of the lye circulation system of the hydrogen production electrolyzer, obtain the lye loss rate of the lye circulation system of the hydrogen production electrolyzer at different lye circulation speeds. The specific acquisition method is as follows: Let the lye circulation system of the hydrogen production electrolyzer operate stably for a period of time T when the lye circulation speed is A. By detecting the specific gravity of the lye before and after time T, the lye loss amount Δlye within time T is obtained. Then the lye loss rate A when the lye circulation speed is A 碱损失 = Δlye ÷ T. Similarly, when the lye circulation speed is B, the lye loss rate can be obtained as B 碱损失 . By analogy, the lye loss rates at various lye circulation speeds can be obtained. These lye loss rates can either all be obtained through actual measurement, or a mathematical model can be established after measuring the lye loss rates at several lye circulation speeds, and the lye loss rates at other lye circulation speeds can be obtained by fitting.

[0041] Step 2) Obtain the real-time lye circulation speed of the lye circulation system of the hydrogen production electrolyzer. The acquisition method is as follows: Measure the lye flow rate added to the electrolyzer 4 in the lye circulation system of the hydrogen production electrolyzer in real time.

[0042] Step 3) According to the corresponding relationship of the lye loss rates at different lye circulation speeds in Step 1) and the real-time lye circulation speed, the real-time lye loss rate of the lye circulation system of the hydrogen production electrolyzer can be obtained.

[0043] Step 4) Add make-up lye to the lye circulation system of the hydrogen production electrolyzer in real time according to the real-time loss rate of the lye. The rate of adding make-up lye to supplement the lye is the same as the real-time loss rate of the lye in step 3), so as to keep the lye concentration stable all the time. Among them, the make-up lye is a KOH solution with a mass fraction of 30% - 35%, and the concentration of the make-up lye should be kept constant during operation.

[0044] Example 2

[0045] In this example, an automatic lye replenishing device for the lye circulation system of a hydrogen production electrolyzer is provided, as Figure 2 shown, including:

[0046] A make-up lye tank 7 for storing make-up lye.

[0047] A make-up lye pump 8 for adding the make-up lye in the make-up lye tank to the lye circulation system of the hydrogen production electrolyzer.

[0048] A flow collector 31 for obtaining the real-time lye circulation rate of the lye circulation system of the hydrogen production electrolyzer; the flow collector 31 is installed on the lye flowmeter 3 to obtain the data of the lye flowmeter 3 in real time.

[0049] A data processor 11, which stores the lye loss rate data corresponding to different lye circulation rates. The data processor controls the flow rate of the make-up lye added by the make-up lye pump to the lye circulation system of the hydrogen production electrolyzer according to the lye loss rate data corresponding to different lye circulation rates stored and the real-time lye circulation rate obtained by the flow collector. A make-up lye controller 81 is provided on the make-up lye pump 8, and the data processor controls the flow rate of the make-up lye added by the make-up lye pump to the lye circulation system of the hydrogen production electrolyzer through the make-up lye controller. The rate of adding make-up lye to supplement the lye is the same as the real-time loss rate of the lye in step 3), keeping the lye concentration stable all the time. In this example, the data processor 11 is a PC computer, and the make-up lye controller 81 uses a PLC controller.

[0050] The lye circulation system of the hydrogen production electrolyzer further includes a make-up lye buffer tank 10, and the make-up lye buffer tank 10 is connected to the make-up lye pump 8, the hydrogen separator 6, the oxygen separator 5, and the lye tank 1 in the lye circulation system of the hydrogen production electrolyzer;

[0051] The make-up lye pump 8 adds the make-up lye to the make-up lye buffer tank, and the make-up lye and the reflux lye from the hydrogen separator and the oxygen separator are mixed in the make-up lye buffer tank and then enter the lye tank. A magnetic stirrer 101 is provided in the make-up lye buffer tank for mixing the liquid in the make-up lye buffer tank. A make-up lye flowmeter 9 is provided between the make-up lye pump 8 and the make-up lye buffer tank 10.

[0052] During the electrolysis operation, the alkaline electrolyte in the lye tank 1 enters the electrolytic cell 4 through the lye flowmeter 3 under the driving force of the lye circulation pump 2, and redox reactions occur in the electrolytic cell 4 to generate hydrogen and oxygen. The hydrogen and part of the mixed lye generated in the electrolytic cell 4 enter the hydrogen separator 5 for separation of hydrogen and lye. The separated hydrogen enters the hydrogen purification device 51 for purification treatment and then enters the downstream of hydrogen. The separated lye flows back to the supplementary lye buffer tank 10. The oxygen and part of the mixed lye generated in the electrolytic cell 4 enter the oxygen separator 6 for separation of oxygen and lye. The separated oxygen enters the oxygen purification device 61 for purification treatment and then enters the downstream of oxygen. The separated lye flows back to the supplementary lye buffer tank 10. During the electrolysis operation, the alkaline electrolyte in the supplementary lye tank 7 enters the supplementary lye buffer tank 10 through the supplementary lye flowmeter 9 under the driving force of the supplementary lye pump 8. During the electrolysis operation, the lye collector 31 continuously collects lye circulation data in real time and feeds back the information to the data processor 11. After completing the data processing, an instruction is sent to the supplementary lye controller 81 to actuate the supplementary lye pump 8, realizing the real-time control of the supplementary lye speed. The hydrogen separator 5, the oxygen separator 6, the lye flowing back to the supplementary lye buffer tank 10, and the supplementary lye pumped by the supplementary lye pump 8 are mixed evenly under the driving force of the magnetic stirrer 101 and then flow back to the lye tank 1 to enter the next cycle.

[0053] For example, during the electrolysis operation, when the electrolytic cell 4 operates continuously and stably at a constant power, the flow rate data of the lye flowmeter 3 collected by the lye collector 31 is a constant, continuous, and stable value, and the supplementary lye speed of the supplementary lye pump 8 is constant, continuous, and stable.

[0054] During the electrolysis operation, when the electrolytic cell 4 operates continuously at a fluctuating power, the flow rate data of the lye flowmeter 3 collected by the lye collector 31 is a fluctuating, continuous value, and the supplementary lye speed of the supplementary lye pump 8 is fluctuating and continuous.

[0055] During the electrolysis operation, when the electrolytic cell 4 operates in a shutdown state, the flow rate data of the lye flowmeter 3 collected by the lye collector 31 is a shutdown state value, and the supplementary lye speed of the supplementary lye pump 8 is in the shutdown state.

[0056] Test Example 1

[0057] The automatic supplementary lye device of the hydrogen production electrolytic cell lye circulation system in Example 2 was used to test a certain hydrogen production electrolytic cell lye circulation system. Before the test, according to the historical operation data of the hydrogen production electrolytic cell lye circulation system, the lye loss speed data corresponding to different lye circulation speeds was input into the data processor. As shown in Table 1, in the state of not turning on the automatic supplementary lye device, the circulating lye flow rate was maintained at 2 m 3 / h, and the electrolysis system was operated for 15 days. The density of the circulating lye decreased from 1.28 g / cm 3 to 1.22 g / cm 3 .

[0058] Table 1 Lye density data per day (unit: g / cm 3 ):

[0059] Day 1 1.2818 Day 2 1.2761 Day 3 1.2724 Day 4 1.2694 Day 5 1.2647 Day 6 1.2576 Day 7 1.2552 Day 8 1.2498 Day 9 1.2456 Day 10 1.2418 Day 11 1.2373 Day 12 1.2343 Day 13 1.2293 Day 14 1.2244 Day 15 1.2204

[0060] With the automatic lye replenishment device turned on, maintain the circulating lye flow rate at 2 m 3 / h, and the electrolysis system operates for 15 days. The data processor 11 automatically retrieves the lye circulation rate based on the circulating lye flow rate, calculates the lye replenishment rate, and controls the lye replenishment pump 8 to inject a 30% KOH lye replenishment solution into the lye replenishment buffer tank 10 at a flow rate of 0.1 m 3 / h. After the electrolysis system operates for 15 days, the density of the circulating lye is always maintained at 1.28 g / cm 3 .

[0061] Then, with the automatic lye replenishment device turned on, adjust the operating power of the hydrogen production electrolyzer to maintain the circulating lye flow rate at 1.5 m 3 / h, and the electrolysis system operates for another 15 days. The data processor 11 automatically retrieves the lye loss rate data based on the circulating lye flow rate, calculates the lye replenishment rate, and controls the lye replenishment pump 8 to inject a 30% KOH lye replenishment solution into the lye replenishment buffer tank 10 at a flow rate of 0.076 m 3 / h. After the electrolysis system operates for 15 days, the density of the circulating lye is always maintained at 1.28 g / cm 3 .

[0062] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or variations derived therefrom are still within the protection scope of this invention.

Claims

1. An automatic alkali replenishment method for the alkali liquor circulation system of a hydrogen production electrolytic cell, characterized in that, It includes the following steps: Step 1) According to the operation data of the alkali liquid circulation system of the hydrogen production electrolyzer, obtain the alkali loss rate of the alkali liquid circulation system of the hydrogen production electrolyzer at different alkali liquid circulation speeds; Step 2) Obtain the real-time alkali liquid circulation speed of the alkali liquid circulation system of the hydrogen production electrolyzer; Step 3) Obtain the real-time alkali loss rate of the alkali liquid circulation system of the hydrogen production electrolyzer based on the alkali loss rates at different alkali liquid circulation speeds of the alkali liquid circulation system of the hydrogen production electrolyzer and the real-time alkali liquid circulation speed; all the alkali loss rates at different alkali liquid circulation speeds are actually measured during the operation of the alkali liquid circulation system of the hydrogen production electrolyzer; the actual measurement method is to keep the alkali liquid circulation system of the hydrogen production electrolyzer running stably at an alkali liquid circulation speed for 15 days, measure the specific gravity of the alkali liquid before and after operation, and calculate the alkali loss rate at this speed through the change in specific gravity; the initial specific gravity of the alkali liquid density is 1.28 g / cm³; Step 4) Add supplementary alkali liquid to the alkali liquid circulation system of the hydrogen production electrolyzer in real time according to the real-time alkali loss rate.

2. The automatic alkali replenishment method for the alkali liquor circulation system of a hydrogen production electrolytic cell according to claim 1, characterized in that, The method for obtaining the real-time alkali liquid circulation flow rate of the alkali liquid circulation system of the hydrogen production electrolyzer is: obtain the real-time alkali liquid flow rate added to the hydrogen production electrolyzer in the alkali liquid circulation system of the hydrogen production electrolyzer.

3. The automatic alkali replenishment method for the alkali liquor circulation system of a hydrogen production electrolytic cell according to claim 1, characterized in that, The supplementary alkali liquid is: a KOH solution with a mass fraction of 30% - 35%.

4. An automatic alkali replenishment device for the alkali liquor circulation system of a hydrogen production electrolytic cell, characterized in that, It includes: A supplementary alkali liquid tank for storing the supplementary alkali liquid; A supplementary alkali liquid pump for adding the supplementary alkali liquid in the supplementary alkali liquid tank into the alkali liquid circulation system of the hydrogen production electrolyzer; A flow rate collector for obtaining the real-time alkali liquid circulation speed of the alkali liquid circulation system of the hydrogen production electrolyzer; A data processor, and the data processor stores the alkali loss rate data corresponding to different alkali liquid circulation speeds; The data processor calculates and controls the flow rate of the supplementary alkali liquid pump adding the supplementary alkali liquid into the alkali liquid circulation system of the hydrogen production electrolyzer according to the real-time alkali liquid circulation speed obtained by the flow rate collector; all the alkali loss rates at different alkali liquid circulation speeds are actually measured during the operation of the alkali liquid circulation system of the hydrogen production electrolyzer; the actual measurement method is to keep the alkali liquid circulation system of the hydrogen production electrolyzer running stably at an alkali liquid circulation speed for 15 days, measure the specific gravity of the alkali liquid before and after operation, and calculate the alkali loss rate at this speed through the change in specific gravity; the initial specific gravity of the alkali liquid density is 1.28 g / cm³; The automatic alkali supplementation device for the alkali liquid circulation system of the hydrogen production electrolyzer adds supplementary alkali liquid to the alkali liquid circulation system of the hydrogen production electrolyzer according to the automatic alkali supplementation method for the alkali liquid circulation system of the hydrogen production electrolyzer described in Claim 1.

5. The automatic alkali replenishment device for the alkali liquor circulation system of a hydrogen production electrolytic cell according to claim 4, characterized in that, The alkali liquid circulation system of the hydrogen production electrolyzer includes an alkali liquid tank, and the alkali liquid tank is connected to the hydrogen production electrolyzer through an alkali liquid circulation pump and an alkali liquid flow meter in sequence; the flow rate collector is installed on the alkali liquid flow meter.

6. The automatic alkali replenishment device for the alkali liquor circulation system of a hydrogen production electrolytic cell according to claim 4, characterized in that, The alkali liquid circulation system of the hydrogen production electrolyzer includes a supplementary alkali buffer tank, and the supplementary alkali buffer tank is connected to the supplementary alkali liquid pump and the hydrogen separator, oxygen separator, and alkali liquid tank in the alkali liquid circulation system of the hydrogen production electrolyzer; The supplementary alkali liquid pump adds the supplementary alkali liquid into the supplementary alkali buffer tank, and the supplementary alkali liquid is mixed with the reflux alkali liquid from the hydrogen separator and oxygen separator in the supplementary alkali buffer tank and then enters the alkali liquid tank.

7. The automatic alkali replenishment device for the alkali liquor circulation system of a hydrogen production electrolytic cell according to claim 6, characterized in that, A supplementary alkali liquid flow meter is provided between the supplementary alkali liquid pump and the supplementary alkali buffer tank.

8. The automatic alkali replenishment device for the alkali liquor circulation system of a hydrogen production electrolytic cell according to claim 6, characterized in that, A stirring device is provided in the supplementary alkali buffer tank.

9. The automatic alkali replenishment device for the alkali liquor circulation system of a hydrogen production electrolytic cell according to claim 8, characterized in that, The stirring device is a magnetic stirrer.

10. The automatic alkali replenishment device for the alkali liquor circulation system of a hydrogen production electrolytic cell according to claim 4, characterized in that, A caustic soda replenishing controller is provided on the caustic soda replenishing pump, and the data processor controls the flow rate of the caustic soda replenishing liquid added to the caustic soda liquid circulation system of the hydrogen production electrolytic cell through the caustic soda replenishing controller.

11. The automatic alkali replenishment device for the alkali liquor circulation system of a hydrogen production electrolytic cell according to claim 10, characterized in that, The caustic soda replenishing controller is a PLC controller or a DCS controller.

12. The automatic alkali replenishment device for the alkali liquor circulation system of a hydrogen production electrolytic cell according to claim 4, characterized in that, The data processor is a PC computer.

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