Green electricity hydrogen production system with one-to-many alkali liquor circulating pumps

Abstract

The utility model relates to a green electricity hydrogen production system with one-to-many alkali liquor circulating pumps, which is characterized in that a common alkali liquor circulating pump and a standby alkali liquor circulating pump of each group of alkali liquor circulating pumps are connected in parallel, the alkali liquor output ends of the common alkali liquor circulating pump and the standby alkali liquor circulating pump are respectively provided with a master regulating valve, and the master regulating valve is provided with a pressure transmitter; alkali liquor output ends of the common alkali liquor circulating pump and the standby alkali liquor circulating pump are connected to a main alkali liquor pipeline, the main alkali liquor pipeline is connected with a plurality of branch alkali liquor pipelines, and the tail end of each branch alkali liquor pipeline is connected with an electrolytic cell; each branch alkali liquor pipeline is provided with a branch flow regulating valve, and each branch flow regulating valve is provided with a flow meter. According to the utility model, the alkali liquor flow of each electrolytic cell is accurately adjusted through the branch flow adjusting valves, and the device is suitable for different load operation modes of each electrolytic cell and different alkali liquor circulation volumes of each electrolytic cell in a green electricity hydrogen production system.

Description

Technical Field

[0001] The utility model relates to a one-to-many green electricity hydrogen production system of alkali solution circulation pumps, belonging to the technical field of alkali solution circulation pumps. Background Art

[0002] Green electricity hydrogen production system refers to the use of photovoltaic energy or wind energy as the power source for electrolysis of water to produce hydrogen. The green electricity power supply is rectified to power the electrolyzer, and the direct current is used to power the post-processing device, and multiple electrolyzers with independent control and switching are connected in parallel. In the conventional green electricity hydrogen production system solution, each electrolyzer corresponds to one alkali liquid circulation pump, and a corresponding backup alkali liquid circulation pump will be set up. Under variable working conditions, some solutions will use variable frequency alkali liquid circulation pumps to deal with it, resulting in excessive land occupation of the gas-liquid separation device and excessive equipment investment. Summary of the invention

[0003] In order to solve the above problems, the utility model discloses a green electricity hydrogen production system with one-to-many alkali solution circulation pumps, and its specific technical solution is as follows:

[0004] A green electricity hydrogen production system with one alkali solution circulation pump to many, comprising a plurality of groups of electrolyzers, each group having a plurality of electrolyzers, each group of electrolyzers sharing a group of alkali solution circulation pumps, each group of alkali solution circulation pumps being provided with a common alkali solution circulation pump and one or more spare alkali solution circulation pumps, the common alkali solution circulation pump and the spare alkali solution circulation pump of each group of alkali solution circulation pumps being connected in parallel, the alkali solution output ends of the common alkali solution circulation pump and the spare alkali solution circulation pump being provided with a main regulating valve, and the main regulating valve being provided with a pressure transmitter, the alkali solution output ends of the common alkali solution circulation pump and the spare alkali solution circulation pump being connected to a main alkali solution pipeline, the main alkali solution pipeline being connected to a plurality of branch alkali solution pipelines, and the end of each branch alkali solution pipeline being connected to an electrolyzer;

[0005] Each branch alkali solution pipeline is provided with a branch flow regulating valve, and each branch flow regulating valve is provided with a flow meter.

[0006] Furthermore, the branch alkali solution pipeline of each electrolytic cell is also provided with a flow display instrument and a flow transmitter instrument.

[0007] Furthermore, each group of alkali solution circulation pumps is provided with a common alkali solution circulation pump and a spare alkali solution circulation pump.

[0008] Furthermore, the common alkali solution circulation pump and the standby alkali solution circulation pump are both industrial frequency pumps.

[0009] Furthermore, the inlet ends of the common alkali solution circulation pump and the standby alkali solution circulation pump are respectively provided with switch valves.

[0010] Furthermore, each group of alkali liquid circulation pumps is also connected in parallel to a bypass alkali liquid circulation pipeline that transports the alkali liquid in the electrolytic cell to the upstream end of the alkali liquid circulation pump. The bypass alkali liquid circulation pipeline is provided with a bypass regulating valve, and the bypass regulating valve is provided with a flow display instrument and a flow transmitter instrument.

[0011] The beneficial effects of the utility model are:

[0012] The utility model arranges a branch flow regulating valve to accurately adjust the alkali solution flow of each electrolytic cell, adapting to the different load operation modes of each electrolytic cell in the green electricity hydrogen production system and the characteristics that the alkali solution circulation volume of each electrolytic cell is different.

[0013] The utility model also provides a bypass pipeline, which is used to open the bypass regulating valve when the alkali solution cannot be completely circulated, so as to ensure that the alkali solution is completely circulated without blocking the pump and protect the alkali solution circulation pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a connection diagram of the utility model.

[0015] List of reference numerals: 1—on-off valve, 2—common alkali solution circulation pump, 3—main line regulating valve, 31—pressure transmitter, 4—main line alkali solution pipeline, 5—standby alkali solution circulation pump, 6—bypass alkali solution circulation pipeline, 7—bypass regulating valve, 8—flow display instrument, 9—flow transmitter, 10—branch alkali solution pipeline, 11—branch flow regulating valve. DETAILED DESCRIPTION

[0016] The present invention is further described below in conjunction with the accompanying drawings and specific implementations. It should be understood that the following specific implementations are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0017] The green electricity hydrogen production system includes several groups of electrolytic cells, each group has several electrolytic cells, each group of electrolytic cells shares a group of alkali solution circulation pumps, and each group of alkali solution circulation pumps is provided with a common alkali solution circulation pump 2 and one or more spare alkali solution circulation pumps 5.

[0018] Combined with Figure 1It can be seen that the attached drawings of this embodiment show that each group of alkali liquid circulation pumps is provided with a common alkali liquid circulation pump 2 and a spare alkali liquid circulation pump 5 as an example. Each group of alkali liquid circulation pumps includes a common alkali liquid circulation pump 2 and a spare alkali liquid circulation pump 5 in parallel, and the alkali liquid output ends of the common alkali liquid circulation pump 2 and the spare alkali liquid circulation pump 5 are both provided with a main regulating valve 3, and the main regulating valve 3 is provided with a pressure transmitter 31, and the alkali liquid output ends of the common alkali liquid circulation pump 2 and the spare alkali liquid circulation pump 5 are connected to the main alkali liquid pipeline 4, and the main alkali liquid pipeline 4 is connected to a plurality of branch alkali liquid pipelines 10, and each branch alkali liquid pipeline 10 is connected to an electrolyzer at the end. Each electrolyzer controls the flow rate independently so as not to affect each other, and each electrolyzer supplies electrolyte according to its own operating load, which is suitable for the operation mode in which the operating load of each electrolyzer changes when the green electricity fluctuates in the green electricity hydrogen production system.

[0019] In order to realize independent control of each branch alkali solution pipeline 10, each branch alkali solution pipeline 10 is provided with a branch flow regulating valve 11, and each branch flow regulating valve 11 is provided with a flow meter. The branch alkali solution pipeline 10 of each electrolytic cell is also provided with a flow display instrument 8 and a flow transmitter 9, which is convenient for data collection and transmission to the control system to realize real-time control.

[0020] The commonly used alkali solution circulation pump 2 and the standby alkali solution circulation pump 5 are both industrial frequency pumps, which are alkali solution circulation pumps with relatively large flow rates.

[0021] The inlet ends of the common alkali solution circulation pump 2 and the standby alkali solution circulation pump 5 are also respectively provided with a switch valve 1. The switch valve 1 is used to switch the common alkali solution circulation pump 2 and the standby alkali solution circulation pump 5. The switch valve 1 is closed when the pump is not in use, and the switch valve 1 is opened when it is in use.

[0022] It is particularly important to note that in the present invention, each group of alkali solution circulation pumps is also connected in parallel to a bypass alkali solution circulation pipeline 6 for conveying the alkali solution in the electrolytic cell to the upstream end of the alkali solution circulation pump. The bypass alkali solution circulation pipeline 6 is provided with a bypass regulating valve 7, and the bypass regulating valve 7 is also provided with a flow meter, a flow display instrument 8 and a flow transmitter 9. Figure 1 It can be seen that the branch flow regulating valve 11 on the branch alkali liquid pipeline 10 is installed in the opposite direction to the bypass regulating valve 7 on the bypass alkali liquid circulation pipeline 6. When the local alkali liquid cannot be completely circulated, the bypass regulating valve 7 on the bypass alkali liquid circulation pipeline 6 is opened to allow the alkali liquid to flow back to the upstream of the alkali liquid circulation pump without blocking the pump. The opening of the bypass regulating valve 7 is adjusted according to the flow rate to protect the alkali liquid circulation pump.

[0023] During normal operation, the alkali liquid from the alkali liquid heat exchanger is transported to the alkali liquid circulation pump through the outlet pipe of the alkali liquid heat exchanger. The alkali liquid circulation pump transports the alkali liquid to the main alkali liquid pipeline 4. The branch flow regulating valves 11 on each branch alkali liquid pipeline 10 adjust the alkali liquid flow rate according to the demand for alkali liquid in each electrolyzer. The alkali liquid enters the electrolyzer to produce hydrogen by water electrolysis. Part of the alkali liquid follows the hydrogen and oxygen into the hydrogen / oxygen liquid separator. The alkali liquid is taken out and replenished to the electrolyzer by opening the branch flow regulating valves 11.

[0024] Each branch alkali solution pipeline 10 independently controls the alkali solution flow rate into its own electrolytic cell.

[0025] In the fluctuating state, during the green electricity fluctuation process, the electrolyzer load is reduced, and the demand for alkali solution in each group of electrolyzers is reduced. Green electricity will be in a fluctuating state due to weather reasons, and the green electricity hydrogen production system will also adjust the switch of the electrolyzer according to the supply of green electricity. When the green electricity load is low, the operating load of some electrolyzers will be reduced or some electrolyzers will be shut down. When the load of some electrolyzers in a group is reduced or shut down, the demand for alkali solution will decrease. However, in the green electricity hydrogen production system, the alkali solution supply circulation system uses stable city electricity and can be supplied normally and stably. In order to cope with the change of green electricity supply, the pressure transmitter 31 is set on the downstream side of the main regulating valve 3 to monitor the alkali liquid pressure in the main alkali liquid pipeline 4. The pressure transmitter 31 sets a pressure threshold. When the pressure transmitter 31 next to the main regulating valve 3 of the electrolytic cell recognizes that the pressure is greater than the pressure threshold, it indicates that the downstream electrolytic cell cannot completely absorb the alkali liquid, and the alkali liquid is stored. The alkali liquid downstream of the alkali liquid circulation pump needs to be discharged in time. At this time, the bypass regulating valve 7 on the bypass alkali liquid circulation pipeline 6 is opened. At this time, the alkali liquid in the main alkali liquid pipeline 4 that cannot be absorbed by the electrolytic cell is discharged from the bypass alkali liquid circulation pipeline 6 and enters the upstream of the alkali liquid circulation pump for circulation. When the pressure transmitter 31 next to the main regulating valve 3 of the electrolytic cell recognizes that the pressure is not greater than the pressure threshold, the bypass regulating valve 7 on the bypass alkali liquid circulation pipeline 6 is immediately closed.

[0026] In the closed state, when the green power supply is extremely low, when all the electrolytic cells in a group are shut down, first open the bypass regulating valve 7 on the bypass alkali solution circulation pipeline 6, and then turn off the alkali solution circulation pump.

[0027] When the common alkali solution circulation pump 2 is abnormal, the switch valve upstream of the common alkali solution circulation pump 2 is closed, and the switch valve of a spare alkali solution circulation pump 5 is opened.

[0028] As for why the alkali solution is designed to enter the downstream of the alkali solution circulation pump, and the bypass reflux is adjusted according to the pressure in the main alkali solution pipeline 4, instead of directly adjusting the opening of the alkali solution circulation pump, the industry background is explained here. Because the green electricity fluctuation is uncertain, the load change or shutdown of the electrolytic cell makes it difficult to accurately monitor the change in the demand for alkali solution. The industry cannot determine the exact alkali solution demand of the electrolytic cell after the load changes, so it is impossible to adjust the alkali solution circulation pump to cope with the green electricity fluctuation. The design of the bypass alkali solution circulation pipeline 6 and the bypass regulating valve 7 can achieve a sufficient supply of alkali solution at the lowest cost without damaging the alkali solution circulation pump, and the monitoring cost is very low, the accuracy is very high, the operability is very large, and it has been applied in the applicant's unit, and it has a good application market prospect.

[0029] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as generally understood by those skilled in the art to which this application belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless defined as herein.

[0030] The term “connection” as used in this application may mean a direct connection between components or an indirect connection between components via other components.

[0031] Based on the above ideal embodiments of the utility model, the relevant staff can make various changes and modifications without deviating from the technical concept of the utility model through the above description. The technical scope of the utility model is not limited to the content of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A green electricity hydrogen production system with one-to-many alkali liquid circulation pumps, comprising several groups of electrolytic cells, each group having several electrolytic cells, characterized in that: Each group of electrolytic cells shares a group of alkali solution circulation pumps, each group of alkali solution circulation pumps is provided with a common alkali solution circulation pump and one or more spare alkali solution circulation pumps, the common alkali solution circulation pump and the spare alkali solution circulation pump of each group of alkali solution circulation pumps are connected in parallel, the alkali solution output ends of the common alkali solution circulation pump and the spare alkali solution circulation pump are both provided with a main line regulating valve, and the main line regulating valve is provided with a pressure transmitter, the alkali solution output ends of the common alkali solution circulation pump and the spare alkali solution circulation pump are connected to a main line alkali solution pipeline, the main line alkali solution pipeline is connected to a plurality of branch alkali solution pipelines, and the end of each branch alkali solution pipeline is connected to an electrolytic cell; Each branch alkali solution pipeline is provided with a branch flow regulating valve, and each branch flow regulating valve is provided with a flow meter.

2. The green electricity hydrogen production system with one-to-many alkali solution circulation pumps according to claim 1 is characterized in that: The branch alkali solution pipeline of each electrolytic cell is also provided with a flow display instrument and a flow transmitter instrument.

3. The green electricity hydrogen production system with one-to-many alkali solution circulation pumps according to claim 1 is characterized in that: Each group of alkali solution circulation pumps is provided with a common alkali solution circulation pump and a spare alkali solution circulation pump.

4. The green electricity hydrogen production system with one-to-many alkali solution circulation pumps according to claim 1 is characterized in that: The commonly used alkali solution circulation pump and the standby alkali solution circulation pump are both industrial frequency pumps.

5. The green electricity hydrogen production system with one-to-many alkali solution circulation pumps according to claim 1 is characterized in that: The inlet ends of the common alkali solution circulation pump and the standby alkali solution circulation pump are respectively provided with switch valves.

6. The green electricity hydrogen production system with one-to-many alkali solution circulation pumps according to claim 1 is characterized in that: Each group of alkali liquid circulation pumps is also connected in parallel to a bypass alkali liquid circulation pipeline that transports the alkali liquid in the electrolytic cell to the upstream end of the alkali liquid circulation pump. The bypass alkali liquid circulation pipeline is provided with a bypass regulating valve, and the bypass regulating valve is provided with a flow display instrument and a flow transmitter instrument.

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