Many-for-one alkaline water electrolysis system capable of independently controlling electrolytic bath alkali liquor circulation volume

Abstract

The utility model relates to a many-to-one alkaline water electrolysis system capable of independently controlling the circulation quantity of alkaline liquor in an electrolytic bath, which is characterized in that hydrogen generated after electrolysis of a hydrogen production device is connected to a hydrogen-liquid separator through a pipeline, and oxygen generated after electrolysis of the hydrogen production device is connected to an oxygen-liquid separator through a pipeline; alkali liquor separated by the hydrogen-liquid separator and the oxygen-liquid separator is conveyed to the hydrogen production devices through an alkali liquor circulating pump, hydrogen separated by the hydrogen-liquid separator is conveyed into a hydrogen washing tower, oxygen separated by the oxygen-liquid separator is conveyed into oxygen for washing, and more than two hydrogen production devices are arranged in parallel. And an alkali liquor automatic regulating valve and a branch alkali liquor flowmeter are arranged on an alkali liquor pipeline at the inlet of each hydrogen production device. The hydrogen production system is provided with a plurality of hydrogen production devices which are connected in parallel, an alkali liquor circulating pump is used for supplying alkali liquor, and downstream common gas-liquid separation equipment is used, so that the occupied area in a plant and the investment of equipment hardware are saved.

Description

Technical Field

[0001] The utility model relates to a many-to-one alkaline water electrolysis system with independently controlled circulation volume of electrolytic cell alkali solution, belonging to the technical field of hydrogen production by water electrolysis. Background Art

[0002] There are several methods for producing hydrogen, such as electrolysis of water, methanol reforming, and natural gas reforming. Each of these methods has its own advantages and disadvantages. Hydrogen production from methanol requires post-purification and will produce carbon-containing gas as a by-product. Hydrogen production from natural gas is similar to hydrogen production from methanol. Among them, hydrogen production from alkaline water electrolysis is a green energy source and has greater advantages. In the prior art, when multiple devices are connected in parallel to produce hydrogen, either a gas-liquid separation system is provided for each electrolyzer (one-to-one mode), or multiple hydrogen production devices are connected to the same gas-liquid separation system (many-to-one mode). Although the one-to-one mode is simple to control, it has problems such as many equipment and high investment. The many-to-one mode has fewer equipment and lower investment, but it is complex to control, involving safety and stability, pressure balance, material balance and other issues among multiple hydrogen production devices. Among them, the difficulty of the many-to-one mode is to use an alkali liquid circulation pump to achieve the balance of the alkali liquid circulation volume of each hydrogen production device in the many-to-one mode. Summary of the invention

[0003] In order to solve the above problems, the utility model discloses a many-to-one alkaline water electrolysis system with independent control of the circulation amount of electrolytic cell alkali solution, and its specific technical scheme is as follows:

[0004] A many-to-one alkaline water electrolysis system with independently controlled alkali solution circulation volume in an electrolytic cell, comprising a hydrogen production device (6), an alkali solution circulation pump (1), a branch alkali solution flow meter (5), an alkali solution automatic regulating valve (4), an alkali solution pressure transmitter (3), an oxygen liquid separator (9), a hydrogen gas-liquid separator (10), an oxygen scrubber (11) and a hydrogen scrubber (12),

[0005] More than two hydrogen production devices (6) are arranged in parallel, and the alkali liquid pipeline at the inlet of each hydrogen production device (6) is provided with an automatic alkali liquid regulating valve (4) and a branch alkali liquid flow meter (5);

[0006] The hydrogen generated by electrolysis of each hydrogen production device (6) is connected to a common hydrogen gas-liquid separator (10) through a respective pipeline; the oxygen generated by electrolysis of each hydrogen production device (6) is connected to a common oxygen liquid separator (9) through a respective pipeline; the alkali liquid separated by the hydrogen gas-liquid separator (10) and the oxygen liquid separator (9) is refluxed to the alkali liquid inlet of the alkali liquid circulation pump (1) through a reflux alkali liquid pipeline, and is transported to the hydrogen production device (6) via the alkali liquid circulation pump (1); the hydrogen separated by the hydrogen gas-liquid separator (10) is sent to a hydrogen washing tower (12); and the oxygen separated by the oxygen liquid separator (9) is sent to an oxygen washing tower (11).

[0007] Furthermore, the alkali liquid pipeline at the outlet side of the alkali liquid circulation pump (1) is provided with an alkali liquid pressure transmitter (3) or a bus alkali liquid flow meter.

[0008] Furthermore, the alkali liquid circulation pump (1) is connected in parallel with a self-circulating pipeline, and a pump-side automatic regulating valve (2) is arranged on the self-circulating pipeline. The alkali liquid pressure transmitter (3) / bus alkali liquid flow meter is located at the downstream side of the connection between the self-circulating pipeline and the alkali liquid pipeline on the outlet side of the alkali liquid circulation pump (1). The alkali liquid pressure transmitter (3) / bus alkali liquid flow meter and the pump-side automatic regulating valve (2) are interlocked to control the pressure at the outlet of the alkali liquid circulation pump (1).

[0009] Furthermore, a hydrogen-side check valve (8) is provided on the hydrogen-alkali liquid outlet pipeline of each hydrogen production device (6).

[0010] Furthermore, an oxygen-side check valve (7) is provided on the oxygen-alkali liquid outlet pipeline of each hydrogen production device (6).

[0011] Furthermore, the alkaline liquid separated by the hydrogen scrubbing tower (12) flows back to the hydrogen liquid separator (10); and the alkaline liquid separated by the oxygen scrubbing tower (11) flows back to the oxygen liquid separator (9).

[0012] Furthermore, the alkali liquid separated by the hydrogen liquid separator (10) and the oxygen liquid separator (9) are merged into the same alkali liquid pipeline, and the alkali liquid pipeline is connected to the alkali liquid inlet side of the alkali liquid circulation pump (1).

[0013] The beneficial effects of the utility model are:

[0014] The utility model sets a plurality of hydrogen production devices in parallel, and uses a alkali liquid circulation pump for alkali liquid supply, which saves the floor space in the plant and the investment in equipment hardware. In order to meet the alkali liquid supply demand, a self-circulating pipeline is set on the alkali liquid circulation pump, and the alkali liquid supply amount of the alkali liquid circulation pump to the hydrogen production device can be adjusted by the pump-side automatic regulating valve on the self-circulating pipeline.

[0015] The utility model provides that a plurality of hydrogen production devices share an oxygen-liquid separator, a hydrogen-liquid separator, an oxygen scrubber and a hydrogen scrubber, which meet the gas treatment requirements and also save land cost, equipment investment cost and adjustment cost.

[0016] The utility model uses an alkali liquid circulation pump, an alkali liquid pressure transmitter, a corresponding branch alkali liquid flow meter and a corresponding alkali liquid automatic regulating valve to collect the electrical signal of each branch alkali liquid flow meter, and controls the alkali liquid circulation amount of each hydrogen production device according to the electrical signal and the control instruction. The pump-side automatic regulating valve on the self-circulation pipeline of each alkali liquid circulation pump is connected to the alkali liquid pressure transmitter on the outlet main pipeline of the alkali liquid circulation pump to collect the electrical signal of the alkali liquid pressure transmitter, and controls the self-circulation amount of the alkali liquid circulation pump according to the electrical signal and the control instruction. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of system connection of the utility model.

[0018] List of reference numerals: 1—alkali solution circulation pump, 2—pump side automatic regulating valve, 3—alkali solution pressure transmitter, 4—alkali solution automatic regulating valve, 5—branch alkali solution flow meter, 6—hydrogen production device, 7—oxygen side check valve, 8—hydrogen side check valve, 9—oxygen liquid separator, 10—hydrogen gas-liquid separator, 11—oxygen scrubber, 12—hydrogen scrubber. DETAILED DESCRIPTION

[0019] 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.

[0020] Combined with Figure 1, it can be seen that the utility model is attached Figure 1 The example of setting four hydrogen production devices 6 is used for demonstration. In actual use, several hydrogen production devices 6 may be set, and the hydrogen production devices 6 are all connected in parallel.

[0021] The utility model is attached Figure 1 The example of setting the alkali liquid pressure transmitter 3 on the outlet pipeline of the alkali liquid circulation pump 1 is used for demonstration. In practical applications, the outlet pipeline of the alkali liquid circulation pump 1 may also be provided with a bus alkali liquid flowmeter instead of the alkali liquid pressure transmitter 3 to adjust the alkali liquid circulation amount.

[0022] The utility model includes an alkali liquid circulation pump 1, a pump-side automatic regulating valve 2, an alkali liquid pressure transmitter 3, an alkali liquid automatic regulating valve 4, a branch alkali liquid flowmeter 5, a hydrogen production device 6, an oxygen-side check valve 7, a hydrogen-side check valve 8, an oxygen-liquid separator 9, a hydrogen-gas-liquid separator 10, an oxygen scrubber 11, and a hydrogen scrubber 12. The oxygen electrolyzed by the hydrogen production device 6 is connected to the oxygen-liquid separator 9 through a parallel pipeline, the hydrogen electrolyzed by the hydrogen production device 6 is connected to the hydrogen-gas-liquid separator 10 through a parallel pipeline, and the alkali liquid separated in the oxygen-liquid separator 9 and the hydrogen-gas-liquid separator 10 is refluxed to the alkali liquid inlet of the alkali liquid circulation pump 1 through the alkali liquid reflux pipeline, and is transported to the hydrogen production device 6 via the alkali liquid circulation pump 1.

[0023] When the utility model is in operation, the alkali liquid circulation amount of the hydrogen production device 6 is interlockedly regulated by the alkali liquid circulation pump 1 and the alkali liquid automatic regulating valve 4 and the branch alkali liquid flowmeter 5 on the alkali liquid circulation pipeline of each hydrogen production device 1, so as to realize the precise control of the flow of the hydrogen production device 6.

[0024] During operation of the utility model, when the number of operating hydrogen production devices 6 increases or decreases, the self-circulation volume of the alkali liquid circulation pump 1 is automatically reduced or increased through the alkali liquid pressure transmitter 3 at the outlet of the alkali liquid circulation pump 1 and the pump-side automatic regulating valve 2 on the self-circulation pipeline to adjust the self-circulation flow rate, thereby compensating the total flow rate supplied by the alkali liquid circulation pump 1 to each hydrogen production device 6 and meeting the alkali liquid flow rate requirements of each hydrogen production device 6.

[0025] The utility model is provided with a self-circulating pipeline and a pump-side automatic regulating valve in the alkali liquid circulation pump 1. The pump-side automatic regulating valve is one of the unique designs of the utility model, which realizes accurate control of the downstream alkali liquid flow of the alkali liquid circulation pump 1 and loose requirements on the upstream alkali liquid flow, and almost does not limit the upstream alkali liquid flow, only has a minimum flow requirement, reduces the trouble of controlling the upstream alkali liquid flow, makes production smoother, and reduces error reporting links.

[0026] One of the unique designs of the utility model is that multiple hydrogen production devices are arranged in parallel. Under the premise of the same hydrogen production amount, the number of alkali liquid circulation pumps and the number of downstream gas-liquid separation equipment are greatly reduced, and the alkali liquid flow rate is independently controlled on the alkali liquid pipeline of each hydrogen production device to achieve no influence between the hydrogen production devices. According to production needs, the hydrogen production device can be fully or partially opened to meet various hydrogen production requirements.

[0027] The term “connection” as used in this application may mean a direct connection between components or an indirect connection between components via other components.

[0028] 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 many-to-one alkaline water electrolysis system with independent control of the circulation amount of alkali solution in an electrolytic cell, comprising a hydrogen production device (6), an alkali solution circulation pump (1), a branch alkali solution flow meter (5), an alkali solution automatic regulating valve (4), an alkali solution pressure transmitter (3), an oxygen liquid separator (9), a hydrogen gas-liquid separator (10), an oxygen scrubber (11) and a hydrogen scrubber (12), It is characterized in that More than two hydrogen production devices (6) are arranged in parallel, and the alkali liquid pipeline at the inlet of each hydrogen production device (6) is provided with an automatic alkali liquid regulating valve (4) and a branch alkali liquid flow meter (5); The hydrogen generated by electrolysis of each hydrogen production device (6) is connected to a common hydrogen gas-liquid separator (10) through a respective pipeline, and the oxygen generated by electrolysis of each hydrogen production device (6) is connected to a common oxygen liquid separator (9) through a respective pipeline. The alkali liquid separated by the hydrogen gas-liquid separator (10) and the oxygen liquid separator (9) is refluxed to the alkali liquid inlet of the alkali liquid circulation pump (1) through the alkali liquid reflux pipeline, and is transported to the hydrogen production device (6) via the alkali liquid circulation pump (1). The hydrogen separated by the hydrogen gas-liquid separator (10) is sent to a hydrogen scrubber (12), and the oxygen separated by the oxygen liquid separator (9) is sent to an oxygen scrubber (11).

2. The many-to-one alkaline water electrolysis system with independent control of electrolytic cell alkali solution circulation volume according to claim 1, characterized in that: The alkali liquid pipeline at the outlet side of the alkali liquid circulation pump (1) is provided with an alkali liquid pressure transmitter (3) or a bus alkali liquid flow meter.

3. The many-to-one alkaline water electrolysis system with independent control of the circulation amount of electrolytic cell alkali solution according to claim 2, characterized in that: The alkali liquid circulation pump (1) is connected in parallel with a self-circulating pipeline, and a pump-side automatic regulating valve (2) is arranged on the self-circulating pipeline. The alkali liquid pressure transmitter (3) / bus alkali liquid flow meter is located at the downstream side of the connection between the self-circulating pipeline and the alkali liquid pipeline on the outlet side of the alkali liquid circulation pump (1). The alkali liquid pressure transmitter (3) / bus alkali liquid flow meter and the pump-side automatic regulating valve (2) are interlocked to control the pressure at the outlet of the alkali liquid circulation pump (1).

4. The many-to-one alkaline water electrolysis system with independent control of electrolytic cell alkali solution circulation volume according to claim 1, characterized in that: A hydrogen-side check valve (8) is provided on the hydrogen-alkali liquid outlet pipeline of each hydrogen production device (6).

5. The many-to-one alkaline water electrolysis system with independent control of electrolytic cell alkali solution circulation volume according to claim 1, characterized in that: An oxygen-side check valve (7) is provided on the oxygen-alkali liquid outlet pipeline of each hydrogen production device (6).

6. The many-to-one alkaline water electrolysis system with independent control of electrolytic cell alkali solution circulation volume according to claim 1, characterized in that: The alkaline liquid separated by the hydrogen scrubbing tower (12) flows back to the hydrogen liquid separator (10); and the alkaline liquid separated by the oxygen scrubbing tower (11) flows back to the oxygen liquid separator (9).

7. The many-to-one alkaline water electrolysis system with independent control of electrolytic cell alkali solution circulation volume according to claim 1, characterized in that: The alkali liquor separated by the hydrogen liquid separator (10) and the oxygen liquid separator (9) are converged into the same converged alkali liquor pipeline, and the converged alkali liquor pipeline is connected to the alkali liquor inlet side of the alkali liquor circulation pump (1).

Images