Novel water electrolysis hydrogen production system

Abstract

The invention discloses a novel water electrolysis hydrogen production system which comprises an electrolytic cell, the hydrogen production system is provided with one or more material coolers for cooling and separating gas-liquid mixed materials at the downstream of the electrolytic cell equipment, and each material cooler comprises a heat source inlet end, a gas outlet end and a liquid outlet end. The liquid outlet ends are connected to the corresponding liquid collecting tanks, the gas outlet ends are connected to downstream gas treatment equipment or a user side, and cooled liquid materials in the liquid collecting tanks are conveyed to the electrolytic bath for recycling. A large alkali liquor separator is omitted, so that the equipment investment and the occupied area are reduced, and the separation process is simplified; a hydrogen / oxygen washing tower is omitted, so that the equipment investment and the occupied area are reduced; therefore, not only is the occupied use area of equipment saved, but also the cost is greatly reduced compared with equipment such as a washing tower and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production by electrolyzing water, and particularly to a novel hydrogen production system by electrolyzing water. Background Art

[0002] In the related technical field of electrolytic cell hydrogen production systems, such as the prior art application number: CN202111291730.8, the hydrogen-alkali liquid mixture and the oxygen-alkali liquid mixture generated after electrolysis of the electrolytic cell respectively enter their respective hydrogen separators and oxygen separators. Subsequently, the mixtures are washed in a hydrogen scrubbing tower and an oxygen scrubbing tower, during which water replenishment, alkali removal, and temperature reduction treatments are carried out. The liquid (including the alkali solution) after washing will enter the hydrogen separator and the oxygen separator again. The separated hydrogen and oxygen respectively enter a hydrogen cooler and an oxygen cooler. The condensed liquid after cooling still enters the hydrogen separator and the oxygen separator respectively. Finally, the cooled hydrogen and oxygen, if qualified, enter their respective hydrogen purification devices and oxygen purification devices, while the unqualified hydrogen and oxygen are both discharged for treatment.

[0003] However, the prior art has obvious defects. First, in terms of equipment configuration, large alkali liquid separators and hydrogen / oxygen scrubbing towers need to be set up. The reason for setting up these large-scale equipment is that in the separation and treatment process, effective separation of the mixed liquid and sufficient washing, alkali removal, and temperature reduction of the gas need to be achieved. However, the consequence is a significant increase in equipment investment, and at the same time, it occupies a large space, resulting in a large floor area, and the separation process is relatively complex, increasing the difficulty of operation and management.

[0004] Secondly, in terms of the separation method, the prior art uses a gas-liquid separator for separation, relying solely on the gravity sedimentation effect to achieve gas-liquid separation, and then washing is carried out. The limitation of this separation method is that it is impossible to precisely control the temperature of the produced gas and the temperature of the separated liquid. The reason lies in the principle limitation of the gravity sedimentation separation method itself. It mainly uses the gas-liquid density difference to achieve separation and is difficult to precisely control the temperature factor. For the subsequent gas users, this inaccurate temperature control is not friendly. Because unstable gas temperature may affect the normal operation of the subsequent equipment and may even reduce the use effect and safety of the gas.

[0005] In view of the above, it is necessary to propose a novel hydrogen production system by electrolyzing water to solve the above problems. Summary of the Invention

[0006] The object of the present invention is to overcome the defects existing in the prior art and provide a more efficient, economical, and convenient electrolytic cell gas separation and treatment solution for controlling the temperature of the produced gas, so as to make up for the many disadvantages in terms of equipment investment, floor area, separation process, and temperature control.

[0007] To achieve the above object, the technical solution of the present invention is as follows: A novel electrolytic water hydrogen production system includes an electrolytic cell. Downstream of the electrolytic cell equipment of the hydrogen production system, there is one or more material coolers for cooling and separating gas-liquid mixed materials. The material cooler includes a heat source inlet end, a gas outlet end, and a liquid outlet end. The liquid outlet end is connected to a corresponding liquid collection tank, and the gas outlet end is connected to downstream gas treatment equipment or a user end. The cooled liquid material in the liquid collection tank is transported to the electrolytic cell for recycling.

[0008] Further, the downstream process routes of the electrolytic cell include a hydrogen treatment route and an oxygen treatment route. Liquid primary collection tanks are respectively provided on the hydrogen treatment route and the oxygen treatment route. The bottom outlet ends of the liquid primary collection tanks on the two downstream process routes are joined and connected to a secondary collection tank. The outlet end of the secondary collection tank is connected to the alkali liquid inlet of the electrolytic cell through a circulation pump.

[0009] Further, the material coolers on the hydrogen treatment route and / or the oxygen treatment route successively include a primary cooler and a secondary cooler. The gas outlet end of the primary cooler is connected to the heat source inlet end of the secondary cooler, and the gas outlet end of the secondary cooler is connected to downstream gas treatment equipment or a user end. The liquid outlet ends of the primary cooler and the secondary cooler are connected in parallel to the liquid collection tank.

[0010] Further, multiple liquid outlet ends in the hydrogen treatment route and the oxygen treatment route are joined and connected to the same liquid primary collection tank, and the two liquid primary collection tanks in the hydrogen treatment route and the oxygen treatment route are joined and connected to the secondary collection tank.

[0011] Further, corresponding liquid primary collection tanks are respectively provided for the material coolers in the hydrogen treatment route and the oxygen treatment route, and the outlet ends of the liquid primary collection tanks are joined and connected to the secondary collection tank.

[0012] Further, a bottom communication pipe is provided between the liquid primary collection tanks in the hydrogen treatment route and the oxygen treatment route.

[0013] Further, the cooling medium of the primary cooler is cooled by circulating water or chilled water, and the cooling medium of the secondary cooler is circulating water or chilled water.

[0014] Further, the gas outlet temperature of the primary cooler is 60±5°C; when the secondary cooler is cooled by circulating water, the gas outlet temperature is 40±5°C, and when the secondary cooler is cooled by chilled water, the gas outlet temperature is 15±5°C.

[0015] Further, a temperature control regulating valve, a temperature sensor, and a pressure sensor are respectively provided on the bottom outlet pipe of the liquid primary collection tank; an oxygen in hydrogen analyzer or a hydrogen in oxygen analyzer can also be provided on this basis; a first temperature sensor and a pressure sensor are respectively provided on the liquid primary collection tank, and a second temperature sensor and a pressure sensor are provided on the pipeline entering the secondary collection tank. The temperature feedback data of the second temperature sensor is used as the basis for the opening ratio of each temperature control regulating valve.

[0016] Further, blow-off pipes are provided at the ends of both the hydrogen treatment route and the oxygen treatment route, and the distance between the blow-off pipes of the two routes is not less than 10 m (designed in accordance with national standards and specifications).

[0017] The advantages and beneficial effects of the present invention are as follows: 1. The cooling medium used in all coolers can be circulating cooling water or chilled water. If a lower requirement for the hydrogen outlet temperature (15 °C) is needed, chilled water is used at the secondary cooler according to the system requirements. By cooling the gas-liquid mixed material, the temperature of the material can be controlled as needed; this avoids the drawbacks of only relying on gravity separation in the prior art.

[0018] 2. The large-scale caustic liquid separator is cancelled, reducing equipment investment and floor area, and simplifying the separation process; the hydrogen / oxygen scrubbing tower is cancelled, reducing equipment investment and floor area; this not only saves the floor area of the equipment, but also significantly reduces the cost compared to equipment such as scrubbing towers.

[0019] 3. The temperature of the caustic liquid entering the electrolytic cell can be regulated according to the operation needs of the electrolytic cell equipment, so that the electrolysis efficiency in the electrolytic cell can be effectively guaranteed. Description of the Drawings

[0020] Figure 1 is one of the process schematic diagrams of a novel electrolytic water hydrogen production system of the present invention; Figure 2 is the second of the process schematic diagrams of a novel electrolytic water hydrogen production system of the present invention; In the figure: 1. Electrolytic cell; 2. Material cooler; 3. Heat source inlet end; 4. Gas outlet end; 5. Liquid outlet end; 6. Liquid collection tank; 7. Hydrogen treatment route; 8. Oxygen treatment route; 9. Liquid primary collection tank; 10. Secondary collection tank; 11. Circulation pump; 12. Primary cooler; 13. Secondary cooler; 14. Bottom connecting pipe; 15. Circulating water cooling; 16. Chilled water; 17. Temperature control regulating valve; 18. First temperature sensor; 19. Second temperature sensor; 20. Blow-off pipe. Detailed Embodiments

[0021] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0022] Embodiment 1: A novel water electrolysis hydrogen production system comprises an electrolyzer 1. The hydrogen production system is provided with one or more material coolers 2 for cooling and separating gas-liquid mixture materials downstream of the electrolyzer 1. The material cooler 2 comprises a heat source inlet end 3, a gas outlet end 4, and a liquid outlet end 5. The liquid outlet end 5 is connected to a corresponding liquid collection tank 6. The gas outlet end 4 is connected to a downstream gas processing device or a user end. The cooled liquid material in the liquid collection tank 6 is transported to the electrolyzer 1 for recycling.

[0023] like Figure 1 As shown, the downstream process route of the electrolyzer 1 includes a hydrogen treatment route 7 and an oxygen treatment route 8. Preferably, a liquid primary collection tank 9 is provided on the hydrogen treatment route 7 and the oxygen treatment route 8, respectively. The bottom outlet ends of the liquid primary collection tanks 9 of the two downstream process routes converge and are connected to a secondary collection tank 10. The outlet end of the secondary collection tank 10 is connected to the alkali liquid inlet of the electrolyzer 1 through a circulating pump 11. In this embodiment, a temperature control regulating valve 17 is further provided on the bottom outlet pipe of the liquid primary collection tank 9, a first temperature sensor 18 is provided on the liquid primary collection tank 9, and a second temperature sensor 19 is provided on the pipeline entering the secondary collection tank 10. The temperature feedback data of the second temperature sensor 19 is used as the opening ratio basis of each temperature control regulating valve 17. In actual use, since customers have high requirements for hydrogen cooling, a lower temperature cooling medium is used and after two-stage heat exchange, the temperature of the condensed alkali solution is also lower, so that the temperature of the liquid primary collection tank 9 on the hydrogen treatment route 7 is lower than that of the liquid primary collection tank 9 on the oxygen treatment route 8. This creates conditions for temperature control of the secondary collection tank 10. If the alkali solution is only separated by gravity, its temperature is maintained at the temperature when it leaves the electrolyzer 1, and after circulating in and out of the electrolyzer 1 many times, it is bound to cause the temperature of the electrolyzer 1 to accumulate and rise, thereby having a negative impact on the efficiency of hydrogen production by electrolysis, and even causing the temperature of the electrolyzer 1 to rise abnormally, accelerating the aging of the gaskets between the bipolar plates.

[0024] Of course, as another improved structure parallel to the foregoing, only one liquid collection tank 6 may be provided, that is, the liquid outlet ends 5 of all the material coolers 2 are connected to the liquid collection tank 6. This embodiment has the advantage of reducing the number of liquid collection tanks 6 provided, so it also brings the advantage of lower equipment cost. The difference is that, compared with the foregoing method, it is not convenient to control the temperature of the lye. All the cooled lye flows into the same liquid collection tank 6, and the natural mixing temperature has strong randomness and is not convenient for precise control.

[0025] In this embodiment, it can be understood that the number of material coolers 2 provided is not limited and can be increased or decreased according to design requirements. Specifically, taking two material coolers 2 as an example, as one way: the material coolers 2 on the hydrogen treatment route 7 and the oxygen treatment route 8 each sequentially include a primary cooler 12 and a secondary cooler 13; As another way, if the customer has a high temperature requirement for hydrogen and needs to reduce the hydrogen to a lower temperature, a tertiary cooler or more can be added on the hydrogen treatment route 7; on the contrary, there are not many requirements for the temperature of oxygen, so at this time, the number of material coolers 2 provided on the oxygen treatment route 8 can be reduced, and only the lye entrained in the gas needs to be separated, or only one material cooler 2 can be provided, so it can be flexibly set according to the needs of the customer.

[0026] Taking the example that there are two material coolers 2 on both the hydrogen treatment route 7 and the oxygen treatment route 8, that is, a primary cooler 12 and a secondary cooler 13 are respectively provided on the two routes. When connecting, the gas outlet end 4 of the primary cooler 12 on each route is connected to the heat source inlet end 3 of the secondary cooler 13, the gas outlet end 4 of the secondary cooler 13 is connected to the downstream gas treatment equipment or the user end, and the liquid outlet ends 5 of the primary cooler 12 and the secondary cooler 13 are connected in parallel to the liquid collection tank 6.

[0027] Embodiment 2: This embodiment is based on Embodiment 1. Specifically, as Figure 1As shown, multiple liquid outlet ends 5 in the hydrogen treatment line 7 and the oxygen treatment line 8 are convergently connected to the same primary liquid collection tank 9, and the two primary liquid collection tanks 9 of the hydrogen treatment line 7 and the oxygen treatment line 8 are convergently connected to the secondary collection tank 10. Since the possible cooling requirements for gases on the two treatment lines are different, the temperatures of the cooling alkali liquids in the hydrogen alkali liquid collection tank and the oxygen alkali liquid collection tank are not the same (according to Embodiment 1, we already know that the cooling requirement on the hydrogen treatment line 7 is higher, so the temperature of the hydrogen alkali liquid collection tank is lower than that of the oxygen alkali liquid collection tank). During use, it can be adjusted according to the temperature of the electrolyzer 1. When the temperature of the electrolyzer 1 is relatively high, more liquid in the hydrogen alkali liquid collection tank can be selected for use, while reducing the use of liquid in the oxygen alkali liquid collection tank, so as to achieve the purpose of reducing the operating temperature of the electrolyzer 1; conversely, the amount of liquid in the oxygen alkali liquid collection tank can be increased. By modulating and mixing the use of the two primary liquid collection tanks 9, the temperature of the secondary collection tank 10 can be controlled accordingly.

[0028] Specifically, temperature control regulating valves 17 are respectively provided on the bottom outlet pipes of the primary liquid collection tanks 9, first temperature sensors 18 are respectively provided on the primary liquid collection tanks 9, and a second temperature sensor 19 is provided on the pipeline entering the secondary collection tank 10. The temperature feedback data of the second temperature sensor 19 is used as the basis for the opening ratio of each temperature control regulating valve 17; in actual use, temperature sensors, pressure sensors can also be added on this basis, a hydrogen in oxygen analyzer provided on the hydrogen treatment line 7, and an oxygen in hydrogen analyzer provided on the oxygen treatment line, and precise control can be further achieved by adding a variety of monitoring parameters to ensure product quality.

[0029] The second temperature sensor 19 serves as a post-stage temperature sensor, which is used to detect temperature data in real time and output corresponding electrical signals; the valve openings of the two upstream temperature control regulating valves 17 can be adjusted to control the flow rate; a PID controller is also provided, and its input port is electrically connected to the second temperature sensor 19, which is used to receive the actual temperature signal transmitted by the temperature sensor, and compare it with the preset temperature value to obtain a temperature deviation; according to the temperature deviation, a control signal is calculated using the PID algorithm; The output end of the PID controller is respectively connected to the control mechanisms of the two temperature control regulating valves 17 (hereinafter corresponding to the first valve and the second valve). According to the calculated control signal, and in accordance with the preset opening ratio rule, the openings of the first valve and the second valve are respectively controlled to adjust the flow rate entering the downstream, so that the downstream temperature tends to the preset temperature value. Among them, the preset opening ratio rule is determined based on experimental data or a theoretical model to ensure precise control of the downstream temperature through the coordinated adjustment of the openings of the two valves under different working conditions.

[0030] Furthermore, a bottom connecting pipe 14 is provided between the liquid primary collection tanks 9 of the hydrogen treatment line 7 and the oxygen treatment line 8. When the liquid levels of the two liquid primary collection tanks 9 differ significantly, the control valve on the bottom connecting pipe 14 can be opened to balance the liquid levels on both sides.

[0031] Embodiment Three: The difference between this embodiment and Embodiment Two is that corresponding liquid primary collection tanks 9 are respectively arranged for the material coolers 2 in the hydrogen treatment line 7 and the oxygen treatment line 8, and the outlet ends of the liquid primary collection tanks 9 are convergently connected to the secondary collection tank 10. As Figure 2 shown, two gas-connected material coolers 2 are respectively provided on the hydrogen treatment line 7 and the oxygen treatment line 8. The liquid outlet ends 5 of the four material coolers 2 are in parallel and are respectively connected to the corresponding liquid primary collection tanks 9. Then, as shown in the figure, four liquid primary collection tanks 9 are provided, and then the four liquid primary collection tanks 9 are convergently connected to the secondary collection tank 10.

[0032] According to the customer's temperature usage requirements for the raw materials, for example, the temperature requirement for hydrogen is 15°C, and the customer does not use oxygen, that is, there is no requirement for oxygen. It is possible to choose to vent the oxygen. Therefore, specific control can be carried out according to the usage requirements as follows. Taking hydrogen as an example, that is, the hydrogen treatment line 7 is cooled by the primary cooler 12 with circulating cooling water (in actual use, other cooling media can also be used according to needs, such as chilled water, ethylene glycol cooling water, Freon refrigeration system, etc.), and the outlet temperature of the primary cooler 12 is controlled to 60°C. The secondary cooler 13 can selectively use circulating cooling water or chilled water 16 for cooling. If circulating cooling water is used, the outlet temperature can be reduced to 40°C, and if chilled water 16 is used, it can be reduced to about 15°C. Similarly, the oxygen treatment line 8 on the oxygen side can also be selectively used in the same way.

[0033] It can be understood that this embodiment can also adopt the form of the temperature sensor and the temperature control regulating valve in Embodiment Two to adjust the temperature of the secondary collection tank 10. Then, three temperature ranges can be formed in the four liquid primary collection tanks 9. That is, the temperatures of the primary coolers 12 in the hydrogen treatment line 7 and the oxygen treatment line 8 are equivalent, which is a temperature range of about 60°C. At the same time, the secondary cooler 13 of the hydrogen treatment line 7 can be controlled to 15°C, which is the second temperature range. And the secondary cooler 13 of the oxygen treatment line 8 can be controlled to 40°C as the third temperature range. Then, by controlling the opening degree of the temperature control regulating valve through the temperature sensor, the temperature of the secondary collection tank 10 can be more precisely controlled.

[0034] Further, blow-off pipes 20 are provided at the ends of both the hydrogen treatment route 7 and the oxygen treatment route 8, and the distance between the blow-off pipes 20 of the two routes is not less than 10 m (designed in accordance with national standard specifications).

[0035] In actual use, at least two or more material coolers 2 are used to replace the hydrogen separator (and oxygen separator) in the original separation system. According to the client's requirements for the hydrogen temperature, if it is < 40 °C, the first and second cooling waters can both use circulating cooling water for cooling; if it is < 15 °C, then the second cooling needs to use 7 °C chilled water 16 for cooling, and the refrigeration method can be either electric refrigeration or bromine chiller refrigeration.

[0036] Since oxygen is not required by the client, the two coolers at the oxygen end can both use circulating water for cooling 15, and chilled water 16 is not considered under any circumstances, saving power consumption.

[0037] The specific working process is as follows: (1) Utilizing the cooling and separation principle of the boring cooler, the hydrogen-alkali liquid mixture and oxygen-alkali liquid mixture electrolyzed by the electrolyzer 1 first enter the primary hydrogen cooler for primary cooling until the alkali liquid is cooled to a reasonable temperature for entering the electrolyzer 1 (such as 60 °C). After the alkali liquid is cooled, it sinks to the hydrogen-alkali liquid collection tank 1. The gas-liquid mixture coming out of the primary hydrogen cooler is cooled to the gas temperature required at the gas outlet of the original gas-liquid separation device (such as 40 °C or 15 °C) by the secondary hydrogen cooler. The alkali liquid after the secondary cooling sinks to the hydrogen-alkali liquid collection tank 2, and the same applies to the oxygen side.

[0038] (2) The alkali liquid collected in the hydrogen-alkali liquid collection tank 1, hydrogen-alkali liquid collection tank 2, oxygen-alkali liquid collection tank 1, and oxygen-alkali liquid collection tank 2 flows into the total alkali liquid collection tank, and then enters the electrolyzer 1 after being circulated by the alkali liquid circulation pump 11, forming a corresponding alkali liquid circulation.

[0039] (3) The qualified hydrogen and oxygen after the secondary cooling enter their respective hydrogen purification devices and oxygen purification devices, and the unqualified hydrogen and oxygen are both vented.

[0040] Advantages after improvement: (1) The cooling medium used in all coolers can adopt circulating cooling water. If a lower requirement for the hydrogen outlet temperature (15 °C) is needed, then chilled water 16 is used at the secondary cooler according to the system needs; (2) The large alkali liquid separator is cancelled, reducing equipment investment and floor area, and simplifying the separation process; (3) The hydrogen / oxygen scrubbing tower is cancelled, reducing equipment investment and floor area.

[0041] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A novel water electrolysis hydrogen production system, comprising an electrolyzer, characterized in that: The hydrogen production system is provided with one or more material coolers for cooling and separating gas-liquid mixture materials downstream of the electrolyzer equipment. The material cooler includes a heat source inlet end, a gas outlet end, and a liquid outlet end. The liquid outlet end is connected to a corresponding liquid collection tank, and the gas outlet end is connected to a downstream gas processing device or a user end. The cooled liquid material in the liquid collection tank is transported to the electrolyzer for recycling.

2. A novel water electrolysis hydrogen production system according to claim 1, characterized in that: The downstream process route of the electrolyzer includes a hydrogen processing route and an oxygen processing route, and liquid primary collecting tanks are respectively provided on the hydrogen processing route and the oxygen processing route. The bottom outlet ends of the liquid primary collecting tanks of the hydrogen processing route and the oxygen processing route converge and are connected to a secondary collecting tank, and the outlet end of the secondary collecting tank is connected to the alkali liquid inlet of the electrolyzer through a circulating pump.

3. A novel water electrolysis hydrogen production system according to claim 2, characterized in that: The material cooler on the hydrogen processing route and / or the oxygen processing route includes a primary cooler and a secondary cooler in sequence, the gas outlet end of the primary cooler is connected to the heat source inlet end of the secondary cooler, the gas outlet end of the secondary cooler is connected to the downstream gas processing equipment or the user end, and the liquid outlet ends of the primary cooler and the secondary cooler are arranged in parallel and connected to the liquid collection tank.

4. A novel water electrolysis hydrogen production system according to claim 3, characterized in that: The multiple liquid outlet ends in the hydrogen processing route and the oxygen processing route are connected to the same liquid primary collection tank, and the two liquid primary collection tanks of the hydrogen processing route and the oxygen processing route are connected to the secondary collection tank.

5. A novel water electrolysis hydrogen production system according to claim 3, characterized in that: Each material cooler in the hydrogen processing route and the oxygen processing route is respectively provided with a corresponding liquid primary collecting tank, and the outlet end of each liquid primary collecting tank is connected to the secondary collecting tank at a confluence.

6. A novel water electrolysis hydrogen production system according to claim 4 or 5, characterized in that: A bottom connecting pipe is arranged between the liquid primary collecting tanks of the hydrogen processing route and the oxygen processing route.

7. A novel water electrolysis hydrogen production system according to claim 3, characterized in that: The cooling medium of the primary cooler is circulating water or chilled water cooling, and the cooling medium of the secondary cooler is circulating water or chilled water cooling.

8. A novel water electrolysis hydrogen production system according to claim 7, characterized in that: The gas outlet temperature of the primary cooler is 60±5°C; when the secondary cooler adopts circulating water cooling, the gas outlet temperature is 40±5°C; when the secondary cooler adopts chilled water cooling, the gas outlet temperature is 15±5°C.

9. A novel water electrolysis hydrogen production system according to claim 2, characterized in that: A temperature control regulating valve, a temperature sensor, a pressure sensor, an oxygen-hydrogen analyzer or a hydrogen-oxygen analyzer are respectively provided on the bottom outlet pipe of the liquid primary collecting tank; a first temperature sensor and a pressure sensor are respectively provided on the liquid primary collecting tank, and a second temperature sensor and a pressure sensor are provided on the pipeline entering the secondary collecting tank, and the temperature feedback data of the second temperature sensor is used as the basis for the opening ratio of each temperature control regulating valve.

10. A novel water electrolysis hydrogen production system according to claim 2, characterized in that: Vent pipes are provided at the ends of the hydrogen processing route and the oxygen processing route, and the distance between the vent pipes of the two routes is not less than 10m.

Images