Novel alkaline water electrolysis hydrogen production process and device

Abstract

The invention provides a novel alkaline water electrolysis hydrogen production process and a novel alkaline water electrolysis hydrogen production device, and relates to the technical field of water electrolysis hydrogen production. The process comprises the following steps: feeding alkali liquor in a cathode chamber and generated hydrogen into a hydrogen processor, and sequentially completing separation of the hydrogen and the alkali liquor, removal of free water in the hydrogen and cooling of the hydrogen so as to obtain crude hydrogen; the alkali liquor in the anode chamber and the generated oxygen are fed into an oxygen treater, separation of the oxygen and the alkali liquor, removal of free water in the oxygen and cooling of the oxygen are completed in sequence, and therefore crude oxygen is obtained; the alkali liquor in the hydrogen treater is sent back into the alkaline water electrolytic tank, and circulation of the hydrogen side alkali liquor is completed; and the alkali liquor in the oxygen treater is sent back into the alkaline water electrolytic tank, and circulation of the alkali liquor on the oxygen side is completed. The number of independent equipment is reduced, and therefore the advantages of flow simplification, reduction of the overall occupied area of the device, cost reduction and the like are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production by electrolyzing water, and in particular to a new alkaline water electrolysis hydrogen production process and device. Background Art

[0002] There are three technical routes for hydrogen production by electrolyzing water: alkaline water electrolysis technology, proton exchange membrane water electrolysis technology, and solid oxide water electrolysis technology. Currently, the main large-scale practical applications are alkaline water electrolysis technology and proton exchange membrane water electrolysis technology.

[0003] Currently, the main core component of the general alkaline water electrolysis hydrogen production device in alkaline water electrolysis technology is the electrolytic cell. The electrolytic cell electrolyzes water into hydrogen and oxygen under the action of direct current, and the reaction formula is: 2H2O = 2H2↑ + O2↑. The electrolytic cell is filled with an alkaline aqueous solution (alkali solution). The electrolytic cell includes a number of anode compartments and cathode compartments, and the anode compartments and cathode compartments are separated by a diaphragm to isolate gases. Hydrogen is produced in the cathode compartment, and the reaction formula is: 4H2O + 4e = 2H2↑ + 4OH - . Oxygen is produced in the anode compartment, and the reaction formula is: 4OH - = O2↑ + 2H2O + 4e.

[0004] Although the current alkaline water electrolysis technology has advantages such as relatively mature technology and good product durability, the corresponding process and device have disadvantages such as more equipment, complex process, large overall floor area of the device, and high maintenance cost. Summary of the Invention

[0005] In view of the above situation, the present invention provides a new alkaline water electrolysis hydrogen production process and device, aiming to solve the technical problems of the existing process and device, such as more equipment, complex process, large overall floor area of the device, and high maintenance cost.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a new alkaline water electrolysis hydrogen production process, including:

[0008] Sending the alkali solution and the generated hydrogen in the cathode compartment of the alkaline water electrolytic cell into a hydrogen processor, and sequentially completing the separation of hydrogen and the alkali solution, the removal of free water in the hydrogen, and the cooling of the hydrogen in the hydrogen processor, so as to obtain crude hydrogen;

[0009] Sending the alkali solution and the generated oxygen in the anode compartment of the alkaline water electrolytic cell into an oxygen processor, and sequentially completing the separation of oxygen and the alkali solution, the removal of free water in the oxygen, and the cooling of the oxygen in the oxygen processor, so as to obtain crude oxygen;

[0010] Return the lye in the hydrogen processor back to the alkaline water electrolyzer to complete the circulation of the lye on the hydrogen side; return the lye in the oxygen processor back to the alkaline water electrolyzer to complete the circulation of the lye on the oxygen side;

[0011] Among them, a preset amount of alkaline tablets must be added to the oxygen processor.

[0012] In some embodiments of the present invention, when removing free water in hydrogen, the free water in hydrogen is removed by the mutual contact of pure water and hydrogen; and / or,

[0013] When removing free water in oxygen, the free water in oxygen is removed by the mutual contact of pure water and oxygen; and / or,

[0014] When cooling hydrogen, heat exchange is carried out by the mutual contact of pure water and hydrogen; and / or,

[0015] When cooling oxygen, heat exchange is carried out by the mutual contact of pure water and oxygen.

[0016] In some embodiments of the present invention, after removing the free water in hydrogen by the mutual contact of pure water and hydrogen, the pure water is sent to the alkaline water electrolyzer; and / or,

[0017] After removing the free water in oxygen by the mutual contact of pure water and oxygen, the pure water is sent to the alkaline water electrolyzer; and / or,

[0018] After carrying out heat exchange by the mutual contact of pure water and hydrogen to cool hydrogen, the pure water is sent to the alkaline water electrolyzer; and / or,

[0019] After carrying out heat exchange by the mutual contact of pure water and oxygen to cool oxygen, the pure water is sent to the alkaline water electrolyzer.

[0020] In a second aspect, the present invention provides a novel alkaline water electrolysis hydrogen production device, including:

[0021] An alkaline water electrolyzer, including a plurality of anode compartments and a plurality of cathode compartments, the anode compartments and the cathode compartments are separated by a diaphragm to isolate gases, and there is lye in both the anode compartments and the cathode compartments;

[0022] A hydrogen processor, including a hydrogen-side first separation chamber, a hydrogen-side second separation chamber, and a hydrogen-side cooling chamber that are integrally connected in sequence in a specified direction;

[0023] An oxygen processor, including an oxygen-side first separation chamber, an oxygen-side second separation chamber, and an oxygen-side cooling chamber that are integrally connected in sequence in a specified direction;

[0024] A recovery pipeline;

[0025] Wherein:

[0026] The first separation chamber on the hydrogen side has a hydrogen-side gas-liquid inlet, which is connected to the cathode chamber. The hydrogen gas and the alkaline solution in the cathode chamber are separated in the first separation chamber on the hydrogen side; the second separation chamber on the hydrogen side is used to remove free water in the hydrogen gas; the cooling chamber on the hydrogen side is used to cool the hydrogen gas;

[0027] The first separation chamber on the oxygen side has an oxygen-side gas-liquid inlet, which is connected to the anode chamber. The oxygen gas and the alkaline solution in the anode chamber are separated in the first separation chamber on the oxygen side; the second separation chamber on the oxygen side is used to remove free water in the oxygen gas; the cooling chamber on the oxygen side is used to cool the oxygen gas;

[0028] The recovery pipeline is used to send the alkaline solution in the hydrogen processor and / or the oxygen processor back to the alkaline water electrolyzer.

[0029] In some embodiments of the present invention, a pure water unit is further included, and both the hydrogen-side cooling chamber and the oxygen-side cooling chamber are connected to the pure water unit.

[0030] In some embodiments of the present invention, the hydrogen processor further includes a hydrogen-side balance pipeline. One end of the hydrogen-side balance pipeline is connected to the first separation chamber on the hydrogen side of the hydrogen processor, and the other end is connected to the pipeline between the hydrogen-side gas-liquid inlet and the cathode chamber. The hydrogen-side balance pipeline is used to balance the air pressure between the cathode chamber and the hydrogen processor; and / or,

[0031] The oxygen processor further includes an oxygen-side balance pipeline. One end of the oxygen-side balance pipeline is connected to the first separation chamber on the oxygen side of the oxygen processor, and the other end is connected to the pipeline between the oxygen-side gas-liquid inlet and the anode chamber. The oxygen-side balance pipeline is used to balance the air pressure between the anode chamber and the oxygen processor.

[0032] In some embodiments of the present invention, the end of the hydrogen-side gas-liquid inlet extends into the first separation chamber on the hydrogen side, the end of the hydrogen-side gas-liquid inlet is closed, and a plurality of through holes are uniformly arranged on the tube wall at the end of the hydrogen-side gas-liquid inlet; the liquid level inside the first separation chamber on the hydrogen side is below the through holes.

[0033] In some embodiments of the present invention, the hydrogen processor further includes a hydrogen-side heat exchange unit, and the hydrogen-side heat exchange unit uses a circulating heat exchange medium to cool the alkaline solution in the hydrogen processor; and / or,

[0034] The oxygen processor further includes an oxygen-side heat exchange unit, and the oxygen-side heat exchange unit uses a circulating heat exchange medium to cool the alkaline solution in the oxygen processor.

[0035] In some embodiments of the present invention, the hydrogen-side heat exchange unit and / or the oxygen-side heat exchange unit includes a U-tube heat exchanger.

[0036] In some embodiments of the present invention, the hydrogen processor further includes a third hydrogen-side separation chamber disposed above the hydrogen-side cooling chamber for gas-liquid separation; and / or,

[0037] The oxygen processor further includes a third oxygen-side separation chamber disposed above the oxygen-side cooling chamber for gas-liquid separation.

[0038] The embodiments of the present invention have at least the following advantages or beneficial effects:

[0039] The hydrogen / oxygen processor adopts a horizontal structure to integrate the first hydrogen / oxygen-side separation chamber, the second hydrogen / oxygen-side separation chamber, and the hydrogen / oxygen-side cooling chamber. Inside the hydrogen / oxygen processor, the separation of hydrogen / oxygen gas and lye, the removal of free water, and the cooling of hydrogen / oxygen gas are realized in an orderly manner, reducing the number of independent devices, thereby bringing benefits such as simplified process, reduced overall floor area of the device, and cost reduction. Among them, the cost reduction is mainly reflected in the highly integrated overall device, which is easy to be skid-mounted and transported in containers; the supporting pipelines are simple, and the number of fittings such as pipe fittings and valves is greatly reduced, thus reducing the construction cost and the later operation and maintenance cost of the device.

[0040] Other features and advantages of the present invention will be described in the following specification, and, in part, will be obvious from the specification, or will be understood by implementing the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0042] Figure 1 FIG. is a flowchart of a new alkaline water electrolysis hydrogen production process;

[0043] Figure 2 FIG. is a structural block diagram of a new alkaline water electrolysis hydrogen production process;

[0044] Figure 3 FIG. is a schematic diagram of the arrangement of the first hydrogen-side separation chamber, the second hydrogen-side separation chamber, and the hydrogen-side cooling chamber from bottom to top;

[0045] Figure 4 FIG. is a structural schematic diagram of a new alkaline water electrolysis hydrogen production device.

[0046] ICON:

[0047] 1 - Hydrogen processor, 11 - First separation chamber on the hydrogen side, 111 - Gas - liquid inlet on the hydrogen side, 12 - Second separation chamber on the hydrogen side, 13 - Cooling chamber on the hydrogen side, 131 - Pure water inlet on the hydrogen side, 14 - Third separation chamber on the hydrogen side, 141 - Wire mesh demister, 15 - Heat exchange unit on the hydrogen side, 16 - Balance pipeline on the hydrogen side, 17 - Pressure control unit on the hydrogen side,

[0048] 2 - Oxygen processor, 21 - First separation chamber on the oxygen side, 211 - Gas - liquid inlet on the oxygen side, 22 - Second separation chamber on the oxygen side, 23 - Cooling chamber on the oxygen side, 231 - Pure water inlet on the oxygen side, 24 - Third separation chamber on the oxygen side, 25 - Heat exchange unit on the oxygen side, 26 - Balance pipeline on the oxygen side, 27 - Pressure control unit on the oxygen side,

[0049] 3 - Pure water unit, 31 - Make - up water pump,

[0050] 41 - Recovery pipeline, 42 - Caustic solution pump, 43 - Filter,

[0051] 5 - Electrolyzer. Detailed implementation manners

[0052] In the following text, only some exemplary embodiments are simply described. As those skilled in the art can recognize, without departing from the spirit or scope of the embodiments of the present invention, the described embodiments can be modified in various different ways.

[0053] In the description of the embodiments of the present invention, it should be understood that the orientation or positional relationships indicated by terms such as "upper", "lower", etc. are based on the orientation or positional relationships shown in the drawings. It is only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the embodiments of the present invention.

[0054] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present invention, the meaning of "several" is one or more than one, unless otherwise clearly and specifically defined.

[0055] In the embodiments of the present invention, unless otherwise clearly specified and limited, terms such as "installed", "connected", "connected to", "fixed" and other terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific situations.

[0056] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0057] Embodiment

[0058] In the first aspect, referring to Figure 1 - Figure 2 , this embodiment provides a new alkaline water electrolysis hydrogen production process, including the following steps:

[0059] Step S100: Send the alkali solution and the generated hydrogen in the cathode chamber of the alkaline water electrolyzer 5 into the hydrogen processor 1, and sequentially complete the separation of hydrogen and alkali solution, removal of free water in hydrogen, and cooling of hydrogen in the hydrogen processor 1, so as to obtain crude hydrogen;

[0060] Send the alkali solution and the generated oxygen in the anode chamber of the alkaline water electrolyzer 5 into the oxygen processor 2, and sequentially complete the separation of oxygen and alkali solution, removal of free water in oxygen, and cooling of oxygen in the oxygen processor 2, so as to obtain crude oxygen; during operation, an appropriate amount of KOH can be replenished in the oxygen processor 2 for the purpose of: supplementing

[0061] Step S200: Send the alkali solution in the hydrogen processor 1 back into the alkaline water electrolyzer 5 to complete the circulation of the alkali solution on the hydrogen side; send the alkali solution in the oxygen processor 2 back into the alkaline water electrolyzer 5 to complete the circulation of the alkali solution on the oxygen side.

[0062] In this embodiment, in step S100, when removing the free water in hydrogen, the free water in hydrogen is removed by the mutual contact of pure water and hydrogen (i.e., water washing); when removing the free water in oxygen, the free water in oxygen is removed by the mutual contact of pure water and oxygen. When cooling hydrogen, heat exchange is carried out by the mutual contact of pure water and hydrogen to achieve the cooling of hydrogen. At the same time, the free water in hydrogen can be further removed; when cooling oxygen, heat exchange is carried out by the mutual contact of pure water and oxygen to achieve the cooling of oxygen. At the same time, the free water in oxygen can be further removed.

[0063] In this embodiment, pure water is used for spray contact washing with hydrogen / oxygen, which is different from the immersion washing in the prior art, greatly improving the washing efficiency and cooling effect.

[0064] In this embodiment, after obtaining the crude hydrogen, the crude hydrogen is boosted to the rated pressure (predetermined pressure) to obtain the product crude hydrogen.

[0065] In this embodiment, in step S100, when the alkaline solution and the generated hydrogen in the cathode chamber of the alkaline water electrolyzer 5 are sent into the hydrogen processor 1, a hydrogen-side balance pipeline 16 is additionally provided. One end of the hydrogen-side balance pipeline 16 is communicated with the first separation chamber 11 on the hydrogen side of the hydrogen processor 1, and the other end is communicated with the pipeline between the hydrogen-side gas-liquid inlet 111 and the cathode chamber of the electrolyzer 5 to balance the air pressure between the cathode chamber and the hydrogen processor 1, so as to prevent hydrogen from generating resistance to the gas-liquid mixture formed by the alkaline solution and hydrogen in the cathode chamber, resulting in obstacles or failures in the feeding of the gas-liquid mixture.

[0066] In this embodiment, in step S100, when the alkaline solution and the generated oxygen in the anode chamber of the alkaline water electrolyzer 5 are sent into the oxygen processor 2, an oxygen-side balance pipeline 26 is additionally provided. One end of the oxygen-side balance pipeline 26 is communicated with the first separation chamber 21 on the oxygen side of the oxygen processor 2, and the other end is communicated with the pipeline between the oxygen-side gas-liquid inlet 111 and the anode chamber of the electrolyzer 5 to balance the air pressure between the anode chamber and the oxygen processor 2, so as to prevent oxygen from generating resistance to the gas-liquid mixture formed by the alkaline solution and oxygen in the cathode chamber, resulting in obstacles or failures in the feeding of the gas-liquid mixture.

[0067] In this embodiment, in step S200, the alkaline solution in the hydrogen processor 1 is first cooled by a circulating heat exchange medium (such as circulating water), and then the alkaline solution is filtered and pressurized and sent back into the alkaline water electrolyzer 5 to complete the circulation of the alkaline solution on the hydrogen side.

[0068] In this embodiment, in step S200, the alkaline solution in the oxygen processor 2 is first cooled by a circulating heat exchange medium (such as circulating water), and then the alkaline solution is filtered and pressurized and sent back into the alkaline water electrolyzer 5 to complete the circulation of the alkaline solution on the oxygen side.

[0069] In a second aspect, referring to Figure 1 - Figure 3 , this embodiment provides a new type of alkaline water electrolysis hydrogen production device, which applies the above new type of alkaline water electrolysis hydrogen production process; the new type of alkaline water electrolysis hydrogen production device mainly includes an alkaline water electrolyzer 5, a hydrogen processor 1, an oxygen processor 2 and a pure water unit 3.

[0070] The alkaline water electrolyzer 5 includes a plurality of anode chambers and a plurality of cathode chambers. The anode chambers and the cathode chambers are separated by a diaphragm to isolate gases. There is alkaline solution (electrolyte) in both the anode chambers and the cathode chambers. The alkaline solution can be a solution such as KOH or NaOH. In a specific implementation scenario, the alkaline solution is preferably a KOH solution with a concentration of 20%-32%. During the electrolysis process, the cations in the alkaline solution are not consumed. In a specific implementation scenario, in this embodiment, KOH tablets are mainly added to the oxygen processor 2. It can be seen from this that the device disclosed in this embodiment directly prepares the alkali by using the oxygen processor 2, does not require an additional alkali solution system, and omits components such as an alkali preparation tank and an alkali preparation pump in the prior art, greatly simplifying the hardware device.

[0071] The system working pressure of the above device is 0.1 - 3.5 MPa. Among them, the working temperature of the alkaline water electrolyzer 5 is 80 - 180 °C, the circulation volume of the lye is 75 - 80 m 3 / h, the hydrogen production capacity is about 10000 Nm 3 / h, the purity of the produced hydrogen is ≥99.9%, the purity of oxygen is ≥99.9%, and it can reach the first-level energy efficiency level (GB32311 large and medium-sized).

[0072] See Figure 3 and Figure 4 , the hydrogen processor 1 includes a first hydrogen-side separation chamber 11, a second hydrogen-side separation chamber 12, and a hydrogen-side cooling chamber 13 that are arranged from bottom to top and integrated after being sequentially connected.

[0073] The first hydrogen-side separation chamber 11 has a hydrogen-side gas-liquid inlet 111. The hydrogen-side gas-liquid inlet 111 is connected to the cathode exhaust pipe and the cathode drain pipe of the cathode chamber. The cathode exhaust pipe uses gas lift to send the generated hydrogen into the first hydrogen-side separation chamber 11; the cathode drain pipe is used to send the lye into the first hydrogen-side separation chamber 11. In the first hydrogen-side separation chamber 11, the lye and hydrogen are separated under the action of gravity, and the hydrogen rises into the second hydrogen-side separation chamber 12 and the hydrogen-side cooling chamber 13 under the action of gas lift.

[0074] In a specific implementation scenario, the end of the hydrogen-side gas-liquid inlet 111 extends into the first hydrogen-side separation chamber 11, the end of the hydrogen-side gas-liquid inlet 111 is closed, and a plurality of through holes for facilitating feeding into the first hydrogen-side separation chamber 11 are uniformly arranged on the end wall of the hydrogen-side gas-liquid inlet 111. The liquid level inside the first hydrogen-side separation chamber 11 is below the through holes of the hydrogen-side gas-liquid inlet 111; the liquid level height inside the first hydrogen-side separation chamber 11 is controlled by the hydrogen-side pressure control unit 17. After the lye and hydrogen enter the first hydrogen-side separation chamber 11 through the through holes, they are separated under the action of gravity.

[0075] The hydrogen processor 1 further includes a hydrogen-side heat exchange unit 15. The hydrogen-side heat exchange unit 15 cools the lye in the hydrogen processor 1 using a circulating heat exchange medium (such as circulating water), and after cooling to about 70 - 50 °C (that is, the lye temperature in the recovery pipe 41 is 70 °C - 75 °C), the lye is sent back into the alkaline water electrolyzer 5 to complete the circulation of the hydrogen-side lye and maintain the stability of the hydrogen-side lye temperature.

[0076] In this embodiment, the hydrogen-side heat exchange unit 15 includes a U-tube heat exchanger, and the U-tube heat exchanger can partially or entirely extend into the first hydrogen-side separation chamber 11. The outer diameter of the U-tube heat exchanger is 1 / 3 to 1 / 4 of the outer diameter of the first hydrogen-side separation chamber 11, and the length of the U-tube heat exchanger extending into the gas-liquid separator can be adjusted according to the required heat exchange area. After the lye located in the first hydrogen-side separation chamber 11 enters the shell side of the U-tube heat exchanger, it exchanges heat with the circulating heat exchange medium in the tube side of the U-tube heat exchanger, and the heat of the lye is carried away by the circulating heat exchange medium, thereby realizing the cooling of the lye. The cooled lye is discharged from the shell side outlet of the U-tube heat exchanger.

[0077] In other embodiments, the hydrogen-side heat exchange unit 15 can also be a spiral tube heat exchanger or a tubular heat exchanger.

[0078] The hydrogen processor 1 further includes a hydrogen-side balance pipeline 16, and the hydrogen-side balance pipeline 16 is used to connect the cathode chamber and the first hydrogen-side separation chamber 11 to balance the air pressure between the cathode chamber and the hydrogen processor 1, and avoid resistance to the feed of the hydrogen-side gas-liquid inlet 111 due to the air pressure difference, resulting in feed obstacles or failures.

[0079] This embodiment does not limit the manner in which the cathode drain pipe sends the lye into the first hydrogen-side separation chamber 11. For example, the lye can be sent into the first hydrogen-side separation chamber 11 through the cathode drain pipe by means of pumping. This embodiment also does not limit the manner in which the recovery pipeline 41 sends the lye back to the alkaline water electrolyzer 5. For example, the lye pump 42 can boost the pressure of the lye through the recovery pipeline 41 and send it back into the alkaline water electrolyzer 5.

[0080] The second hydrogen-side separation chamber 12 is connected to the pure water unit 3, and the pure water unit 3 sends pure water into the second hydrogen-side separation chamber 12. In the second hydrogen-side separation chamber 12, the pure water contacts the hydrogen in a spraying manner to remove the free water in the hydrogen.

[0081] In this embodiment, in order to ensure the effect of removing the free water in the hydrogen, a packing layer is provided in the second hydrogen-side separation chamber 12, and the packing layer is preferably a packing suitable for water washing such as ceramic flakes.

[0082] This embodiment does not limit the manner in which the pure water unit 3 sends pure water into the second hydrogen-side separation chamber 12. For example, the pure water unit 3 can be connected to the second hydrogen-side separation chamber 12 through a makeup water pump 31.

[0083] The hydrogen-side cooling chamber 13 has a hydrogen-side pure water inlet 131, and the hydrogen-side pure water inlet 131 is connected to the pure water unit 3, and the pure water unit 3 sends pure water into the hydrogen-side cooling chamber 13. In the hydrogen-side cooling chamber 13, the pure water and the hydrogen contact each other in a spraying manner for heat exchange to cool the hydrogen. At the same time, the falling pure water enters the second hydrogen-side separation chamber 12 as water for water washing to remove the free water in the hydrogen, so as to obtain crude hydrogen with less water content.

[0084] This embodiment does not limit the way the pure water unit 3 sends pure water into the hydrogen-side cooling chamber 13. For example, the pure water unit 3 can be connected to the hydrogen-side cooling chamber 13 through a make-up water pump 31.

[0085] The first hydrogen-side separation chamber 11 is connected to the alkaline water electrolyzer 5 through a recovery pipeline 41. The pure water and the alkali solution separated from the hydrogen that fall into the first hydrogen-side separation chamber 11 are sent back into the alkaline water electrolyzer 5 as materials for water electrolysis after being filtered by a filter 43 and pressurized by an alkali solution pump 42, completing the circulation of the hydrogen-side alkali solution.

[0086] The hydrogen processor 1 further includes a third hydrogen-side separation chamber 14 disposed above the hydrogen-side cooling chamber 13. A wire mesh demister 141 is provided in the third hydrogen-side separation chamber 14, which further realizes gas-liquid separation and reduces the water content of the crude hydrogen.

[0087] In a specific implementation scenario, the above-mentioned first hydrogen-side separation chamber 11 adopts a vertical or horizontal structure; the second hydrogen-side separation chamber 12, the hydrogen-side cooling chamber 13, and the third hydrogen-side separation chamber 14 form a gas treatment structure, and the gas treatment structure is detachably connected to the gas-phase outlet of the first hydrogen-side separation chamber 11, so that users can determine whether to select this gas treatment structure according to their needs.

[0088] As can be seen from the above, in the hydrogen processor 1, the separation of hydrogen and alkali solution is first completed by using the specific gravity difference below, and then during the rising process of hydrogen, the free water in hydrogen is removed and the hydrogen is cooled, thereby obtaining crude hydrogen. The crude hydrogen discharged from the hydrogen-side cooling chamber 13 can be boosted to obtain product crude hydrogen with a rated pressure after being boosted by a boost component such as a thin-film regulating valve and a compressor. The product crude hydrogen can be sent to a subsequent purification unit to obtain hydrogen with a higher purity. The crude hydrogen discharged from the hydrogen-side cooling chamber 13 can reach the rated pressure after being boosted by boost components such as a thin-film regulating valve and a compressor. These boost components can be integrated on the hydrogen processor 1 according to the scenario requirements. At the lower part of the hydrogen processor 1, the pure water and the alkali solution separated from the hydrogen that fall into the first hydrogen-side separation chamber 11 are returned to the electrolyzer 5 as materials for water electrolysis, completing the circulation of the hydrogen-side alkali solution.

[0089] The overall structure of the oxygen processor 2 is similar to that of the hydrogen processor 1, and specifically includes an oxygen-side first separation chamber 21, an oxygen-side second separation chamber 22, and an oxygen-side cooling chamber 23 that are arranged from bottom to top and integrally connected in sequence.

[0090] The first oxygen-side separation chamber 21 has an oxygen-side gas-liquid inlet 211. The oxygen-side gas-liquid inlet 211 is connected to the anode exhaust pipe and the anode liquid discharge pipe of the anode chamber. The anode exhaust pipe uses gas lift to send the generated oxygen into the first oxygen-side separation chamber 21; the anode liquid discharge pipe is used to send the lye into the first oxygen-side separation chamber 21. In the first oxygen-side separation chamber 21, the lye and oxygen are separated under the action of gravity, and the oxygen rises into the second oxygen-side separation chamber 22 and the oxygen-side cooling chamber 23 under the action of gas lift.

[0091] In a specific implementation scenario, the end of the oxygen-side gas-liquid inlet 211 extends into the first oxygen-side separation chamber 21. The end of the oxygen-side gas-liquid inlet 211 is closed, and a plurality of through holes for facilitating feeding into the first oxygen-side separation chamber 21 are uniformly arranged on the end wall of the oxygen-side gas-liquid inlet 211. The liquid level inside the first oxygen-side separation chamber 21 is below the through holes of the oxygen-side gas-liquid inlet 211; the height of the liquid level inside the first oxygen-side separation chamber 21 is controlled by the oxygen-side pressure control unit 27. After the lye and oxygen enter the first oxygen-side separation chamber 21 through the through holes, they are separated under the action of gravity.

[0092] The oxygen processor 2 further includes an oxygen-side heat exchange unit 25. The oxygen-side heat exchange unit 25 uses a circulating heat exchange medium (such as circulating water) to cool the lye in the oxygen processor 2, so as to send the lye back to the alkaline water electrolyzer 5 to complete the circulation of the oxygen-side lye and maintain the stability of the temperature of the oxygen-side lye.

[0093] In this embodiment, the oxygen-side heat exchange unit 25 includes a U-tube heat exchanger, and the U-tube heat exchanger can partially or fully extend into the first oxygen-side separation chamber 21. The outer diameter of the U-tube heat exchanger is 1 / 3 to 1 / 4 of the outer diameter of the first oxygen-side separation chamber 21, and the length of the U-tube heat exchanger extending into the gas-liquid separator can be adjusted according to the required heat exchange area. The lye located in the first oxygen-side separation chamber 21 enters the shell side of the U-tube heat exchanger and exchanges heat with the circulating heat exchange medium in the tube side of the U-tube heat exchanger. The heat of the lye is taken away by the circulating heat exchange medium, thereby realizing the cooling of the lye, and the cooled lye is discharged from the shell side outlet of the U-tube heat exchanger.

[0094] In other embodiments, the oxygen-side heat exchange unit 25 can also be a spiral tube heat exchanger or a tubular heat exchanger.

[0095] The oxygen processor 2 further includes an oxygen-side balance pipeline 26. The oxygen-side balance pipeline 26 is used to connect the anode chamber and the first oxygen-side separation chamber 21 to balance the air pressure between the anode chamber and the oxygen processor 2, and avoid resistance to the feeding of the oxygen-side gas-liquid inlet 211 due to the air pressure difference, resulting in feeding obstacles or failures.

[0096] This embodiment does not limit the manner in which the anode drain pipe sends the lye into the first oxygen-side separation chamber 21. For example, the lye can be sent into the first oxygen-side separation chamber 21 through the anode drain pipe by means of pumping. This embodiment also does not limit the manner in which the recovery pipe 41 sends the lye back to the alkaline water electrolyzer 5. For example, the lye pump 42 can be used to boost the pressure of the lye through the recovery pipe 41 and then send it back into the alkaline water electrolyzer 5.

[0097] The second oxygen-side separation chamber 22 is connected to the pure water unit 3, and the pure water unit 3 sends pure water into the second oxygen-side separation chamber 22. In the second oxygen-side separation chamber 22, the pure water contacts the oxygen in a spraying manner to remove the free water in the oxygen.

[0098] In this embodiment, in order to ensure the effect of removing the free water in the oxygen, a packing layer is provided in the second oxygen-side separation chamber 22. The packing layer is preferably ceramic flakes, or other packings suitable for water washing can also be used.

[0099] This embodiment does not limit the manner in which the pure water unit 3 sends pure water into the second oxygen-side separation chamber 22. For example, the pure water unit 3 can be connected to the second oxygen-side separation chamber 22 through the make-up water pump 31.

[0100] The oxygen-side cooling chamber 23 has an oxygen-side pure water inlet 231, and the oxygen-side pure water inlet 231 is connected to the pure water unit 3. The pure water unit 3 sends pure water into the oxygen-side cooling chamber 23. The pure water and the oxygen in the oxygen-side cooling chamber 23 contact each other in a spraying manner for heat exchange to cool the oxygen. At the same time, the falling pure water enters the second oxygen-side separation chamber 22 as water for water washing to remove the free water in the oxygen, so as to obtain crude oxygen with less water content.

[0101] This embodiment does not limit the manner in which the pure water unit 3 sends pure water into the oxygen-side cooling chamber 23. For example, the pure water unit 3 can be connected to the oxygen-side cooling chamber 23 through the make-up water pump 31.

[0102] The first oxygen-side separation chamber 21 is connected to the alkaline water electrolyzer 5 through the recovery pipe 41. The pure water that falls into the first oxygen-side separation chamber 21 and the lye separated from the oxygen are filtered by the filter 43 and boosted by the lye pump 42, and then sent back into the alkaline water electrolyzer 5 as materials for water electrolysis to complete the circulation of the lye on the oxygen side.

[0103] The oxygen processor 2 further includes a third oxygen-side separation chamber 24 provided above the oxygen-side cooling chamber 23. A wire mesh demister 141 is provided in the third oxygen-side separation chamber 24, which further realizes gas-liquid separation and reduces the water content of the crude oxygen.

[0104] In a specific implementation scenario, the above-mentioned first oxygen-side separation chamber 21 adopts a vertical or horizontal structure; the second oxygen-side separation chamber 22, the oxygen-side cooling chamber 23, and the third oxygen-side separation chamber 24 form a gas treatment structure, and the gas treatment structure is detachably connected to the gas-phase outlet of the first oxygen-side separation chamber 21, so that users can determine whether to select the gas treatment structure according to their needs.

[0105] As can be seen from the above content, in the oxygen processor 2, the separation of oxygen and lye is first completed by using the specific gravity difference below, and then during the upward movement of oxygen, the free water in the oxygen is removed and the oxygen is cooled, thereby obtaining crude oxygen. The crude oxygen discharged from the oxygen-side cooling chamber 23 can be boosted to obtain product crude oxygen with a rated pressure, and the product crude oxygen can be sent to the subsequent purification unit to obtain oxygen with a higher purity. The crude oxygen discharged from the oxygen-side cooling chamber 23 can reach the rated pressure after being boosted by boosting components such as a thin-film regulating valve and a compressor. These boosting components can be integrated on the oxygen processor 2 according to the scenario requirements. At the lower part of the oxygen processor 2, the pure water and the lye separated from the oxygen that fall into the first oxygen-side separation chamber 21 return to the electrolytic cell 5 as the materials for water electrolysis to complete the circulation of the oxygen-side lye.

[0106] Combined with the above content, this embodiment has at least the following beneficial effects:

[0107] First, the hydrogen / oxygen processor integrates the first hydrogen / oxygen-side separation chamber, the second hydrogen / oxygen-side separation chamber, and the hydrogen / oxygen-side cooling chamber. In the hydrogen / oxygen processor, the separation of hydrogen / oxygen and lye, the removal of free water, and the cooling of hydrogen / oxygen are realized from bottom to top, reducing the number of independent devices, thereby bringing benefits such as simplified process, reduced overall floor area of the device, and reduced cost. Among them, the cost reduction is reflected in that due to the overall high integration of the device, the supporting pipelines are simple, and the number of fittings such as pipe fittings and valves is greatly reduced, thereby reducing the construction cost and the later operation and maintenance cost of the device.

[0108] Second, in the prior art, the method of supplying lye to the alkaline water electrolysis cell 5 by a lye supply unit (including but not limited to a lye preparation tank and a lye pump) is often used to maintain the stability of the lye in the alkaline water electrolysis cell 5. However, in this embodiment, on the one hand, the preparation of lye is realized by adding KOH tablets to the first oxygen-side separation chamber 21, and on the other hand, the pure water supplied by the pure water unit 3 to the hydrogen processor 1 and the oxygen processor 2 will return to the alkaline water electrolysis cell 5 together with the lye as the materials for water electrolysis (make-up water), thereby maintaining the stability of the lye in the alkaline water electrolysis cell 5, and there is no need to additionally configure a lye supply unit, further simplifying the process, reducing the number of supporting devices, and reducing the cost.

[0109] Thirdly, in the prior art, a connecting pipe is provided between the hydrogen separator and the oxygen separator. The device disclosed in this embodiment cancels the connecting pipe between the hydrogen separator and the oxygen separator, which can ensure that there is no gas leakage between hydrogen and oxygen and avoid the risk of explosion caused by the mixing of hydrogen and oxygen.

[0110] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Without conflict, the embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A novel alkaline water electrolysis hydrogen production process, characterized in that, Comprising: The lye and the generated hydrogen in the cathode chamber of the alkaline electrolyzer are sent into a hydrogen processor, where the separation of hydrogen and lye, the removal of free water in the hydrogen, and the cooling of the hydrogen are sequentially completed to obtain crude hydrogen. The lye and the generated oxygen in the anode chamber of the alkaline electrolyzer are sent into an oxygen processor, where the separation of oxygen and lye, the removal of free water in the oxygen, and the cooling of the oxygen are sequentially completed to obtain crude oxygen. The lye in the hydrogen processor is sent back into the alkaline electrolyzer to complete the circulation of the lye on the hydrogen side. The lye in the oxygen processor is sent back into the alkaline electrolyzer to complete the circulation of the lye on the oxygen side. Wherein, a preset amount of alkaline tablets must be added to the oxygen processor.

2. The novel alkaline water electrolysis hydrogen production process according to claim 1, characterized in that: When removing the free water in the hydrogen, the free water in the hydrogen is removed by the mutual contact of pure water and hydrogen; and / or, When removing the free water in the oxygen, the free water in the oxygen is removed by the mutual contact of pure water and oxygen; and / or, When cooling the hydrogen, heat exchange is carried out by the mutual contact of pure water and hydrogen; and / or, When cooling the oxygen, heat exchange is carried out by the mutual contact of pure water and oxygen.

3. The novel alkaline water electrolysis hydrogen production process according to claim 2, characterized in that, Further comprising: After removing the free water in the hydrogen by the mutual contact of pure water and hydrogen, the pure water is sent into the alkaline electrolyzer; and / or, After removing the free water in the oxygen by the mutual contact of pure water and oxygen, the pure water is sent into the alkaline electrolyzer; and / or, After cooling the hydrogen by the mutual contact of pure water and hydrogen for heat exchange, the pure water is sent into the alkaline electrolyzer; and / or, After cooling the oxygen by the mutual contact of pure water and oxygen for heat exchange, the pure water is sent into the alkaline electrolyzer.

4. A novel alkaline water electrolysis hydrogen production device, characterized in that, Comprising: An alkaline electrolyzer, including a plurality of anode chambers and a plurality of cathode chambers, the anode chambers and the cathode chambers are separated by a diaphragm to isolate gases, and there is lye in both the anode chambers and the cathode chambers; A hydrogen processor, including a hydrogen-side first separation chamber, a hydrogen-side second separation chamber, and a hydrogen-side cooling chamber that are sequentially connected from bottom to top and integrated into one body; An oxygen processor, including an oxygen-side first separation chamber, an oxygen-side second separation chamber, and an oxygen-side cooling chamber that are sequentially connected from bottom to top and integrated into one body; A recovery pipeline; Wherein: The hydrogen-side first separation chamber has a hydrogen-side gas-liquid inlet, which is communicated with the cathode chamber, and the hydrogen generated in the cathode chamber and the lye in the cathode chamber are separated in the hydrogen-side first separation chamber; the hydrogen-side second separation chamber is used to remove the free water in the hydrogen; the hydrogen-side cooling chamber is used to cool the hydrogen; The oxygen-side first separation chamber has an oxygen-side gas-liquid inlet, which is communicated with the anode chamber, and the oxygen generated in the anode chamber and the lye in the anode chamber are separated in the oxygen-side first separation chamber; the oxygen-side second separation chamber is used to remove the free water in the oxygen; the hydrogen-side cooling chamber is used to cool the oxygen; The recovery pipeline is used to send the lye in the hydrogen processor and / or the oxygen processor back to the alkaline water electrolyzer; the temperature of the lye in the recovery pipeline is 70°C - 75°C.

5. The novel alkaline water electrolysis hydrogen production device according to claim 4, characterized in that, It further includes: A pure water unit; Both the hydrogen side cooling chamber and the oxygen side cooling chamber are connected to the pure water unit.

6. The novel alkaline water electrolysis hydrogen production device according to claim 4, wherein The hydrogen processor further includes a hydrogen side balance pipeline. One end of the hydrogen side balance pipeline is communicated with the first hydrogen side separation chamber of the hydrogen processor, and the other end is communicated with the pipeline between the hydrogen side gas-liquid inlet and the cathode chamber. The hydrogen side balance pipeline is used to balance the air pressure between the cathode chamber and the hydrogen processor; and / or, The oxygen processor further includes an oxygen side balance pipeline. One end of the oxygen side balance pipeline is communicated with the first oxygen side separation chamber of the oxygen processor, and the other end is communicated with the pipeline between the oxygen side gas-liquid inlet and the anode chamber. The oxygen side balance pipeline is used to balance the air pressure between the anode chamber and the oxygen processor.

7. The novel alkaline water electrolysis hydrogen production device according to claim 4, characterized in that : The end of the hydrogen side gas-liquid inlet extends into the interior of the first hydrogen side separation chamber, and the end of the hydrogen side gas-liquid inlet is closed; A plurality of through holes are uniformly arranged on the end wall of the hydrogen side gas-liquid inlet, and the liquid level inside the first hydrogen side separation chamber is below the through holes.

8. The novel alkaline water electrolysis hydrogen production device according to claim 4, characterized in that : The hydrogen processor further includes a hydrogen side heat exchange unit, and the hydrogen side heat exchange unit uses a circulating heat exchange medium to cool the lye in the hydrogen processor; and / or, The oxygen processor further includes an oxygen side heat exchange unit, and the oxygen side heat exchange unit uses a circulating heat exchange medium to cool the lye in the oxygen processor.

9. The novel alkaline water electrolysis hydrogen production device according to claim 8, wherein, The hydrogen side heat exchange unit and / or the oxygen side heat exchange unit includes a U-tube heat exchanger.

10. The novel alkaline water electrolysis hydrogen production device according to any one of claims 4-9, wherein The hydrogen processor further includes a third hydrogen side separation chamber arranged above the hydrogen side cooling chamber for gas-liquid separation; and / or, The oxygen processor further includes a third oxygen side separation chamber arranged above the oxygen side cooling chamber for gas-liquid separation.

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