T-coupling type gas-liquid separation and condensation integrated device for hydrogen production by electrolysis of water and working process

Abstract

This invention relates to the technical field of water electrolysis hydrogen production equipment, providing a T-type coupled gas-liquid separation and condensation integrated device and its working process for water electrolysis hydrogen production. The device includes a housing comprising a horizontal separation section, a vertical condensation section, and a liquid collection section. The liquid collection section and the vertical condensation section are located on the same vertical plane, with the vertical condensation section positioned above the liquid collection section. The horizontal separation section, vertical condensation section, and liquid collection section are connected and together form a T-shaped structure. A gas deflection channel is formed at the intersection of the vertical condensation section and the horizontal separation section, causing the gas after initial liquid removal to change from horizontal flow to vertical upward flow. The deflection channel forms a flow guiding transition structure to prevent secondary entrainment caused by eddies in the gas flow. This invention employs a three-stage synergistic purification process, achieving excellent gas-liquid separation and demisting efficiency. It utilizes a three-stage synergistic treatment mechanism of gas-liquid cyclone initial separation + deep condensation dehydration + wire mesh demisting, combined with a strong swirling flow field to enhance droplet detachment and a flow equalization plate to optimize airflow distribution, effectively removing electrolyte droplets and water vapor entrained in the gas.

Description

Technical Field

[0001] This invention relates to the technical field of water electrolysis hydrogen production equipment, and in particular to a T-type coupled gas-liquid separation and condensation integrated device and its working process for gas-liquid separation, condensation and dehumidification, demisting and purification and liquid recovery in water electrolysis hydrogen production systems. It is applicable to alkaline water electrolysis hydrogen production, proton exchange membrane (PEM) water electrolysis hydrogen production, and anion exchange membrane (AEM) water electrolysis hydrogen production systems, and can be widely used in industrial scenarios such as large-scale green hydrogen production and hydrogen energy pilot projects. Background Technology

[0002] During operation, a water electrolysis hydrogen production system generates hydrogen at the cathode and oxygen at the anode. Since the electrolysis reaction typically takes place in an environment containing water or electrolyte, the hydrogen or oxygen output from the electrolyzer often carries liquid water, electrolyte droplets, and saturated or near-saturated water vapor. If these liquids or water vapor are not effectively removed, it can lead to problems such as increased load on subsequent gas purification units, liquid accumulation in pipelines, valve corrosion, instrument malfunction, increased water content in hydrogen storage equipment, and increased system energy consumption. In severe cases, it can affect the lifespan of the electrolyzer and the safety of system operation.

[0003] Existing water electrolysis hydrogen production systems typically employ independent gas-liquid separators, coolers, condensers, demisters, and liquid return devices for staged treatment. While this approach achieves some gas-liquid separation and dehumidification, it involves numerous devices, large footprints, complex piping connections, high pressure losses, and lacks tight coupling between gas-liquid separation, condensation recovery, and electrolyte replenishment. Especially under high current density, fluctuating loads, or rapid start-up and shutdown conditions, the content of entrained droplets and water vapor in the gas varies significantly, making it difficult for conventional single-separation structures to simultaneously handle droplet separation, water vapor condensation, micro-droplet capture, and liquid recovery. Therefore, it is necessary to provide a compact, highly integrated, and efficient integrated gas-liquid separation and condensation device and method suitable for continuous operation of water electrolysis hydrogen production. This would reduce the subsequent purification load, improve water and electrolyte recovery efficiency, and enhance system operational stability. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a T-type coupled gas-liquid separation and condensation integrated device for hydrogen production via water electrolysis. The device includes a shell made of duplex stainless steel 2205 or 316L, with an anti-corrosion treatment on the inner wall to adapt to the corrosive conditions of hydrogen production via electrolysis. It can be applied to gas-liquid separation and condensation dehumidification on the hydrogen side and / or oxygen side of alkaline, proton exchange membrane, anion exchange membrane, and solid oxide water electrolysis hydrogen production systems.

[0005] The shell includes a horizontal separation section, a vertical condensation section, and a liquid collection section. The liquid collection section and the vertical condensation section are located on the same vertical plane, with the vertical condensation section located above the liquid collection section. The horizontal separation section, the vertical condensation section, and the liquid collection section are connected and together form a T-shaped structure. A gas deflection channel is formed at the intersection of the vertical condensation section and the horizontal separation section, which changes the gas flow from horizontal to vertically upward after initial liquid removal. The deflection channel forms a flow guiding transition structure to avoid secondary entrainment caused by eddies in the gas flow. A gas-liquid mixing inlet is provided on one side of the shell, and the gas-liquid mixing inlet is located on the left side of the horizontal separation section; The bottom of the housing is provided with a liquid phase outlet and the top is provided with a gas phase outlet; the gas phase outlet is provided with a wire mesh demister to remove residual liquid droplets in the gas. The horizontal separation section is equipped with a gas-liquid swirling internal component, which is used to make the gas-liquid mixture entering the horizontal separation section form a swirling flow and achieve preliminary gas-liquid separation; The vertical condensation section is equipped with a condensation tube bundle, which is used to exchange heat with the gas after preliminary liquid removal, so that the water vapor entrained in the gas is condensed into liquid water. The liquid collection section is equipped with a return pipeline for replenishing the mixture of condensate and electrolyte in the liquid collection section back to the electrolysis system.

[0006] Furthermore, the gas-liquid mixture inlet is connected to the gas-liquid output pipeline of the electrolyzer or the water electrolysis hydrogen production system.

[0007] Furthermore, the gas-liquid swirling internals include swirling tube internals, axial swirling blade internals, corrugated swirling plate internals, or spiral flow channel internals.

[0008] Furthermore, the condenser tube bundle includes multiple heat exchange tubes, through which a cooling medium is circulated, and the gas flows outside the heat exchange tubes and exchanges heat with the cooling medium; the condenser tube bundle adopts a shell-and-tube, U-tube, finned tube, coil, or microchannel heat exchange structure, and the tube bundle material is duplex stainless steel.

[0009] Furthermore, the cooling medium is cooling water, low-temperature circulating water, ethylene glycol aqueous solution, or process refrigerant; the temperature of the cooling medium is controlled at 20-30℃, and the gas temperature at the gas phase outlet is reduced to below 40℃ by adjusting the flow rate.

[0010] Furthermore, a liquid guiding structure is provided below the condenser tube bundle, and the two ends of the liquid guiding structure are respectively connected to the inner walls on both sides of the shell; the liquid guiding structure is used to guide the condensate to the lower part of the vertical condensation section and flow into the liquid collection section; the liquid guiding structure is a conical liquid guiding funnel to prevent the condensate from being entrained by the rising gas when flowing along the tube wall.

[0011] The wire mesh demister can be a metal wire mesh demister or a corrugated wire mesh demister, and can be made of materials such as stainless steel, titanium, and nickel alloy. The wire mesh count is 80 mesh, which can effectively remove droplets larger than 3-5μm, with a separation efficiency of up to 99% or more.

[0012] Furthermore, the liquid collection section is equipped with at least one of the following: a liquid level detection element, a drain outlet, a replenishment outlet, an inspection outlet, and a sewage outlet; the liquid level detection element is a differential pressure level gauge or a float level switch, used to monitor the liquid level in real time and interlock with the return pipeline for control.

[0013] Furthermore, the reflux pipeline is equipped with at least one of the following: a reflux valve, a reflux pump, a check valve, a filter, and a liquid level interlock control element; the filter has a filtration accuracy of 10-20μm and is used to remove minute impurities in the mixture to avoid contaminating the electrolysis system.

[0014] Furthermore, the horizontal separation section, vertical condensation section, and liquid collection section are an integrated shell structure, or are combined to form an integrated device through flange, welding, clamp, or threaded connection methods; the shell material is duplex stainless steel 2205 or 316L stainless steel, and the inner wall is treated with anti-corrosion to adapt to the corrosive working conditions of electrolytic hydrogen production.

[0015] Another aspect of the present invention provides a working process for a T-type coupled gas-liquid separation and condensation integrated system for hydrogen production by water electrolysis, the working process including: S1. The gas-liquid mixture generated during the electrolysis of water to produce hydrogen is fed into the device through the gas-liquid mixing inlet on the left side of the horizontal separation section; S2. The gas-liquid mixture generates swirling motion through the gas-liquid swirling internals set in the horizontal separation section, and achieves preliminary gas-liquid separation under the action of centrifugal force, inertia and gravity. S3. After initial liquid removal, the gas changes direction in the T-shaped junction area and enters the vertical condensation section vertically upward. S4. The gas exchanges heat with the condenser tube bundle located at the top of the vertical condensation section, causing the water vapor entrained in the gas to condense into liquid water. S5. Liquid water formed by the condensation of water vapor in the gas drips onto the liquid guiding structure located below the condenser tube bundle under the action of gravity. The liquid guiding structure receives the liquid and collects it along its liquid guiding surface. The liquid is then guided to the lower part of the vertical condensation section and flows into the liquid collection section, where it merges with the liquid obtained by cyclone separation. S6. The gas after condensation and dehumidification is passed through a wire mesh demister to remove residual droplets and then discharged from the upper gas phase outlet of the vertical condensation section. S7. The mixture of condensate and electrolyte in the collection section is returned to the electrolysis system via the return pipeline.

[0016] The present invention has the following beneficial effects: (1) The integrated T-shaped coupling structure of the present invention has high integration and reduces both the footprint and pressure drop. The present invention integrates four major functions, namely horizontal cyclone separation, vertical condensation dehumidification, wire mesh defoaming, and liquid collection and reflux, into a single T-shaped structure device, replacing the traditional multi-stage series scheme of separator, cooler, demister and return tank. The number of devices and connecting pipelines are greatly reduced, the system footprint is reduced by more than 40%, the overall operating pressure drop is significantly reduced, the system energy consumption and leakage risk are effectively reduced, and it is suitable for the intensive installation requirements of water electrolysis hydrogen production equipment.

[0017] (2) The present invention adopts a three-stage synergistic purification, with excellent gas-liquid separation and demisting efficiency. It adopts a three-stage synergistic treatment mechanism of gas-liquid cyclone initial separation + condensation deep dehydration + wire mesh demisting, combined with strong cyclone field to enhance droplet detachment and flow equalization plate to optimize airflow distribution, which can efficiently remove electrolyte droplets and water vapor entrained in the gas; the wire mesh demister can capture tiny droplets of 3–5 μm and above, with a separation efficiency of over 99%, which greatly reduces the load of subsequent purification and drying units.

[0018] (3) The flow field optimization design of the present invention avoids secondary entrainment from the source. The T-shaped intersection area is set with a flow guiding transition structure to eliminate the airflow turning into vortex; a conical liquid guiding structure is configured below the condenser tube bundle so that the condensate flows into the liquid collection section along a predetermined path, preventing the condensate from being entrained by the rising airflow; the swirling internals adopt a low cone angle and reasonable length-to-diameter ratio design to prevent boundary layer peeling and ensure a stable and efficient separation process.

[0019] (4) The present invention adopts countercurrent condensation heat exchange, with precise temperature control and stable dehumidification effect. The condenser tube bundle adopts a countercurrent heat exchange layout, and the temperature of the cooling medium can be controlled at 20–30℃. The outlet gas temperature can be stably reduced to below 40℃, so that water vapor can be fully condensed. It is suitable for the high temperature conditions of 70–90℃ for electrolysis of water to produce hydrogen. The heat exchange efficiency is high, the dehumidification effect is not affected by load fluctuations, and the operation stability is strong.

[0020] (5) The present invention features closed-loop liquid recovery, which maximizes the utilization rate of electrolyte and water resources. The liquid collection section collects the separated liquid and condensate in a unified manner. With the help of the liquid level interlocking automatic reflux system, the mixture of condensate and electrolyte is continuously / intermittently replenished to the electrolysis system. The liquid recovery rate is ≥99%, which greatly reduces electrolyte loss and pure water consumption, reduces the operating cost of hydrogen production, and maintains the stability of the liquid level in the electrolysis system.

[0021] (6) The present invention adopts anti-corrosion materials and has strong structural adaptability, and is compatible with all working conditions. The shell and key components are made of duplex stainless steel 2205 / 316L, titanium and nickel alloy anti-corrosion materials, and the inner wall is treated with anti-corrosion. It can be adapted to alkaline, PEM, AEM and other electrolytic water hydrogen production systems, and simultaneously meet the gas-liquid treatment requirements of hydrogen side and oxygen side. It has outstanding corrosion resistance and pressure bearing capacity, and the service life of the equipment is significantly extended.

[0022] (7) The present invention has a high degree of automation and convenient operation and maintenance. The liquid level detection and reflux system interlock control does not require frequent manual intervention; the wire mesh demister, filter and other components adopt modular design, which makes disassembly, cleaning and replacement easy; the equipment is equipped with inspection port and sewage outlet, and the daily maintenance cost is low, which can meet the requirements of long-term continuous operation of the water electrolysis hydrogen production system.

[0023] (8) The present invention has a wide load adaptability and can be adapted to the hydrogen production gas-liquid cyclone internals and condensation system coupled with renewable energy. It can be adapted to a wide load adjustment of 20%–110%, and can cope with the frequent load fluctuations of renewable energy such as wind power and photovoltaic coupled with water electrolysis to produce hydrogen. It can ensure the stable separation, condensation and defoaming effect across the entire load range and has strong industrial applicability. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the integrated device of the present invention.

[0025] Figure 2 This is a schematic diagram of the workflow of the present invention. Detailed Implementation

[0026] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. However, these embodiments are not intended to limit the present invention. Any similar structures and similar variations of the present invention should be included in the protection scope of the present invention. The commas in the present invention all indicate the relationship between and. The English letters in the present invention are case-sensitive.

[0027] like Figure 1 As shown, this invention provides a T-type coupled gas-liquid separation and condensation integrated device for hydrogen production by water electrolysis, including a shell 1. The shell material is duplex stainless steel 2205 or 316L stainless steel, and the inner wall is treated with anti-corrosion to adapt to the corrosive working conditions of hydrogen production by electrolysis. It can be applied to the gas-liquid separation and condensation dehumidification on the hydrogen side and / or oxygen side of alkaline, proton exchange membrane, anion exchange membrane, and solid oxide water electrolysis hydrogen production systems.

[0028] The housing 1 includes a horizontal separation section 11, a vertical condensation section 12, and a liquid collection section 13. The liquid collection section 13 and the vertical condensation section 12 are located on the same vertical plane, with the vertical condensation section 12 located above the liquid collection section 13. The horizontal separation section 11, the vertical condensation section 12, and the liquid collection section 13 are connected and together form a T-shaped structure. A gas deflection channel is formed at the intersection of the vertical condensation section 12 and the horizontal separation section 11, which changes the gas flow from horizontal to vertical upward after initial liquid removal. The deflection channel forms a flow guiding transition structure to avoid secondary entrainment caused by eddies in the gas flow. The horizontal separation section 11, the vertical condensation section 12, and the liquid collection section 13 are an integral housing structure, or can be combined to form an integrated device through flanges, welding, clamps, or threaded connections.

[0029] A gas-liquid mixing inlet 14 is provided on one side of the housing 1, and the gas-liquid mixing inlet 14 is located on the left side of the horizontal separation section 11; the gas-liquid mixing inlet 14 is connected to the gas-liquid output pipeline of the electrolyzer or the water electrolysis hydrogen production system, and is used to receive the gas-liquid mixture from the water electrolysis hydrogen production system. The bottom of the housing 1 is provided with a liquid phase outlet 15, and the top is provided with a gas phase outlet 16. The gas phase outlet 16 is provided with a wire mesh demister 17 for removing residual liquid droplets from the gas. The wire mesh demister 17 can be a metal wire mesh demister or a corrugated wire mesh demister, and can be made of materials such as stainless steel, titanium, and nickel alloy. The wire mesh count is 80 mesh, which can effectively remove droplets larger than 3-5μm, with a separation efficiency of over 99%, and is used to remove residual liquid droplets from the gas. A gas phase outlet is opened at the top of the vertical condensation section. The gas purified by separation, condensation, and demisting is discharged from the gas phase outlet and enters the subsequent purification, drying, storage, or use system.

[0030] The horizontal separation section 11 is equipped with a gas-liquid swirling internal component 111, which is used to create a swirling flow in the gas-liquid mixture entering the horizontal separation section and achieve preliminary gas-liquid separation. The gas-liquid swirling internal component 111 includes a swirling tube type internal component, an axial swirling blade type internal component, a corrugated swirling plate type internal component, or a spiral flow channel type internal component. After the gas-liquid mixture enters the horizontal separation section, it forms a swirling flow under the action of the gas-liquid swirling internal component. The denser droplets and electrolyte mist droplets migrate towards the wall under the action of centrifugal force, inertia, and gravity, and finally flow into the liquid collection section, completing the preliminary gas-liquid separation. A closed end, a buffer chamber, or a liquid baffle zone may be provided at the right end of the horizontal separation section to reduce liquid entrainment and promote liquid phase sedimentation into the liquid collection section.

[0031] The vertical condensation section 12 is equipped with a condenser tube bundle 121 for heat exchange with the gas after preliminary liquid removal, condensing the water vapor entrained in the gas into liquid water. The condenser tube bundle 121 includes multiple heat exchange tubes, through which a cooling medium flows. The gas flows outside the heat exchange tubes and exchanges heat with the cooling medium. The condenser tube bundle adopts a shell-and-tube, U-tube, finned tube, coil, or microchannel heat exchange structure, and the tube bundle material is duplex stainless steel. The cooling medium is cooling water, low-temperature circulating water, ethylene glycol aqueous solution, or process refrigerant. The temperature of the cooling medium is controlled at 20-30℃, and the gas temperature at the gas phase outlet is reduced to below 40℃ by flow regulation.

[0032] Below the condenser tube bundle 121, there is a liquid guiding structure 122. The two ends of the liquid guiding structure 122 are respectively connected to the inner walls on both sides of the shell. The liquid guiding structure is used to guide the condensate to the lower part of the vertical condensation section and into the liquid collection section. The liquid guiding structure is a conical liquid guiding funnel to prevent the condensate from being entrained by the rising gas when it flows along the tube wall.

[0033] The collection section 13 is equipped with a return pipeline for replenishing the condensate and electrolyte mixture in the collection section back to the electrolysis system. The return pipeline is equipped with at least one of the following: a return valve, a return pump, a check valve, a filter, and a level interlock control element. The return pump can be matched to the rated flow rate according to the collection volume to ensure timely replenishment of the mixture and maintain a stable liquid level in the electrolysis system. The filter has a filtration accuracy of 10-20μm to remove minute impurities in the mixture and prevent contamination of the electrolysis system. The collection section is equipped with at least one of the following: a level detection element, a drain port, a replenishment port, a maintenance port, and a sewage outlet. The level detection element is a differential pressure level gauge or a float level switch, used to monitor the liquid level in real time and interlock with the return pipeline for control.

[0034] like Figure 2 As shown, another aspect of the present invention provides a T-type coupled gas-liquid separation and condensation integrated process for hydrogen production by water electrolysis, the process comprising: S1. The gas-liquid mixture generated during the electrolysis of water to produce hydrogen is fed into the device through the gas-liquid mixing inlet on the left side of the horizontal separation section; S2. The gas-liquid mixture generates swirling motion through the gas-liquid swirling internals set in the horizontal separation section, and achieves preliminary gas-liquid separation under the action of centrifugal force, inertia and gravity. S3. After initial liquid removal, the gas changes direction in the T-shaped junction area and enters the vertical condensation section vertically upward. S4. The gas exchanges heat with the condenser tube bundle located at the top of the vertical condensation section, causing the water vapor entrained in the gas to condense into liquid water. S5. Liquid water formed by the condensation of water vapor in the gas drips onto the liquid guiding structure located below the condenser tube bundle under the action of gravity. The liquid guiding structure receives the liquid and collects it along its liquid guiding surface. The liquid is then guided to the lower part of the vertical condensation section and flows into the liquid collection section, where it merges with the liquid obtained by cyclone separation. S6. The gas after condensation and dehumidification is passed through a wire mesh demister to remove residual droplets and then discharged from the upper gas phase outlet of the vertical condensation section. S7. The mixture of condensate and electrolyte in the collection section is returned to the electrolysis system via the return pipeline.

[0035] Example 1 This embodiment is applied to an alkaline water electrolysis hydrogen production system (hydrogen side). The system has a rated hydrogen production capacity of 500 Nm³ / h, an operating pressure of 1.6 MPa, an operating temperature of 90℃, an electrolyte of 30% KOH alkaline solution, and a gas-liquid mixture of hydrogen gas, vapor, and KOH electrolyte droplets.

[0036] The T-type coupled gas-liquid separation and condensation integrated device described in this embodiment uses an integrated duplex stainless steel 2205 shell for the horizontal separation section, vertical condensation section, and liquid collection section, with anti-corrosion treatment on the inner wall. The horizontal separation section has a length-to-diameter ratio of 1.5, and a gas-liquid mixture inlet is opened on the left side, which is connected to the hydrogen outlet pipeline of the electrolytic cell. The horizontal separation section is equipped with an axial swirling blade type gas-liquid swirling internal component. The guide blades are inclined at an angle of 30° to the axis of the horizontal separation section, with 7 blades and a blade thickness of 4mm. The cone angle of the separation chamber of the swirling internal component is 12°, and a closed buffer chamber is set at the right end of the horizontal separation section.

[0037] The length ratio of the vertical condensation section to the horizontal separation section is 2:1, and an arc-shaped flow guide transition structure is set at the intersection. A condenser tube bundle is installed on the upper part of the vertical condensation section. The tube bundle is made of duplex stainless steel 2205. The cooling medium inlet is located below the tube bundle and the outlet is located above it. 25℃ low-temperature circulating water is introduced, and the gas phase outlet gas temperature is controlled at 38℃ by flow regulation. A conical liquid guide hopper is set below the condenser tube bundle, and a perforated flow equalization plate is installed in the vertical condensation section and below the condenser tube bundle.

[0038] A stainless steel wire mesh demister with an 80-mesh screen is installed inside the vertical condensation section and above the condenser tube bundle. It can effectively remove droplets larger than 3-5μm with a separation efficiency of over 99%. A gas phase outlet is opened at the top of the vertical condensation section, which is connected to the subsequent hydrogen purification unit.

[0039] The liquid collection section has a funnel-shaped structure with a volume of 0.5 m³. It is equipped with a differential pressure level gauge and has a drain port, maintenance port, and sewage outlet. The liquid collection section is connected to the electrolyte circulation loop of the electrolytic cell through a return pipeline. The return pipeline is equipped with an electric return valve, a magnetic return pump, a 15 μm precision filter, and a check valve in sequence, which are interlocked with the differential pressure level gauge for control.

[0040] Operation process: The gas-liquid mixture enters the horizontal separation section through the gas-liquid mixture inlet at a flow rate of 20 m / s. Under the action of the axial swirling blade internals, a strong swirling flow field is formed. Electrolyte droplets migrate towards the wall under the action of centrifugal force, inertia, and gravity, and flow into the collection section to complete the initial separation. The hydrogen gas after initial dehydration enters the vertical condensation section vertically upward through the guide transition structure. After being rectified by the flow equalization plate, it exchanges heat with the condenser tube bundle in a countercurrent manner. Water vapor condenses into liquid water and flows into the collection section through the conical liquid guide hopper. The dehumidified hydrogen gas is discharged from the gas phase outlet after the residual micro-droplets are removed by the wire mesh demister. The purity of the outlet hydrogen gas is ≥99.8%, and the moisture content is ≤5 g / m³. When the liquid level in the collection section reaches 75% (upper limit), the reflux valve opens and the reflux pump starts to replenish the condensate and electrolyte mixture to the electrolysis system. When the liquid level drops to 25% (lower limit), the reflux system automatically shuts off to achieve continuous and stable replenishment.

[0041] Example 2 This embodiment is applied to a PEM proton exchange membrane electrolysis water production system (hydrogen + oxygen on both sides). The system has a rated hydrogen production capacity of 200 Nm³ / h, an operating pressure of 2.0 MPa, an operating temperature of 80℃, and the gas-liquid mixture is a mixture of hydrogen / oxygen-water vapor-pure water droplets. The device described in this invention is symmetrically configured on both sides.

[0042] The T-type coupled gas-liquid separation and condensation integrated device described in this embodiment uses a flange-connected 316L stainless steel shell for the horizontal separation section, vertical condensation section, and liquid collection section. The horizontal separation section is equipped with a corrugated cyclone plate gas-liquid cyclone internal component, which uses centrifugal cyclone separation technology to enhance bubble aggregation and droplet detachment. A liquid baffle zone is set at the right end of the horizontal separation section.

[0043] Finned tube condenser bundles are installed at the top of the vertical condensation section. The bundles are made of duplex stainless steel and the cooling medium is a 22°C ethylene glycol aqueous solution, which controls the gas outlet temperature at 36°C. An arc-shaped liquid guide plate is installed below the condenser bundles, and a droplet collection plate is added inside the vertical condensation section to improve condensation efficiency.

[0044] The vertical condensation section is equipped with a titanium alloy corrugated wire mesh demister with an 80-mesh screen, which is more corrosion resistant and suitable for high-purity PEM electrolysis of water to produce hydrogen. It can efficiently remove micro-droplets larger than 3-5 μm with a separation efficiency of 99.9%.

[0045] A float level switch is installed inside the liquid collection section, and a 10 μm precision filter is installed on the return pipeline to prevent impurities from entering the membrane electrode assembly of the PEM electrolyzer. The upper limit of the liquid level is set to 70%, and the lower limit is set to 30%, so as to realize intermittent automatic replenishment.

[0046] Operation process: The hydrogen / oxygen gas-liquid mixture produced by the electrolyzer enters through the inlet of the horizontal separation section of the corresponding device, and completes preliminary gas-liquid separation under the action of the corrugated swirl plate internals; the gas enters the vertical condensation section vertically upward through the guide transition structure, where it exchanges heat and dehydrates with the finned condenser tube bundle, and the condensate flows into the collection section through the arc-shaped liquid guide plate; after the gas is deeply purified by the titanium alloy wire mesh demister, it is discharged from the gas phase outlet, with the purity of hydrogen / oxygen both ≥99.9%; when the liquid level in the collection section triggers the interlock signal, the reflux system automatically replenishes the condensate to the pure water tank of the PEM electrolysis water hydrogen production system, with no electrolyte contamination throughout the process, which is suitable for high-purity hydrogen preparation requirements.

[0047] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

Claims

1. A T-coupled gas-liquid separation and condensation integrated device for hydrogen production by electrolysis of water, characterized by, The device includes a housing, which comprises a horizontal separation section, a vertical condensation section, and a liquid collection section. The liquid collection section and the vertical condensation section are located on the same vertical plane, with the vertical condensation section located above the liquid collection section. The horizontal separation section, the vertical condensation section, and the liquid collection section are connected and together form a T-shaped structure. A gas deflection channel is formed at the intersection of the vertical condensation section and the horizontal separation section, causing the gas after preliminary liquid removal to change from horizontal flow to vertical upward flow. The deflection channel forms a flow guiding transition structure to prevent the gas flow from generating eddies that could lead to secondary entrainment. A gas-liquid mixing inlet is provided on one side of the shell, and the gas-liquid mixing inlet is located in the horizontal separation section; The bottom of the housing is provided with a liquid phase outlet and the top is provided with a gas phase outlet; the gas phase outlet is provided with a wire mesh demister to remove residual liquid droplets in the gas. The horizontal separation section is equipped with a gas-liquid swirling internal component, which is used to make the gas-liquid mixture entering the horizontal separation section form a swirling flow and achieve preliminary gas-liquid separation; The vertical condensation section is equipped with a condensation tube bundle, which is used to exchange heat with the gas after preliminary liquid removal, so that the water vapor entrained in the gas is condensed into liquid water. The liquid collection section is equipped with a return pipeline for replenishing the mixture of condensate and electrolyte in the liquid collection section back to the electrolysis system.

2. The T-coupled gas-liquid separation and condensation integrated device for hydrogen production by water electrolysis according to claim 1, characterized in that, The gas-liquid mixture inlet is connected to the gas-liquid output pipeline of the electrolyzer or water electrolysis hydrogen production system.

3. The T-type coupled gas-liquid separation and condensation integrated device for hydrogen production by water electrolysis according to claim 1, characterized in that, The gas-liquid swirling internals include swirling tube internals, axial swirling blade internals, corrugated swirling plate internals, or spiral flow channel internals.

4. The T-coupled gas-liquid separation and condensation integrated device for hydrogen production by water electrolysis according to claim 1, characterized in that, The condenser tube bundle includes multiple heat exchange tubes, through which a cooling medium is introduced. The gas flows outside the heat exchange tubes and exchanges heat with the cooling medium. The condenser tube bundle adopts a shell-and-tube, U-tube, finned tube, coil, or microchannel heat exchange structure, and the tube bundle material is duplex stainless steel. 5.The T-coupled gas-liquid separation and condensation integrated device for hydrogen production by water electrolysis of claim 4, characterized in that, The cooling medium is cooling water, low-temperature circulating water, ethylene glycol aqueous solution, or process refrigerant.

6. The T-coupled gas-liquid separation and condensation integrated device for hydrogen production by water electrolysis according to claim 1, characterized in that, A liquid guiding structure is provided below the condenser tube bundle, and the two ends of the liquid guiding structure are respectively connected to the inner walls on both sides of the shell; the liquid guiding structure is used to guide the condensate to the lower part of the vertical condensation section and flow into the liquid collection section; the liquid guiding structure is a conical liquid guiding funnel to prevent the condensate from being entrained by the rising gas when flowing along the tube wall.

7. The T-coupled gas-liquid separation and condensation integrated device for hydrogen production by water electrolysis according to claim 1, characterized in that, The liquid collection section is equipped with at least one of the following: a liquid level detection element, a drain outlet, a replenishment outlet, an inspection outlet, and a sewage outlet; the liquid level detection element is a differential pressure level gauge or a float level switch, used to monitor the liquid level in real time and interlock with the return pipeline for control. 8.The T-coupled gas-liquid separation and condensation integrated device for hydrogen production by water electrolysis of claim 1, wherein, The return pipeline is equipped with at least one of the following: a return valve, a return pump, a check valve, a filter, and a liquid level interlock control element. 9.The T-coupled gas-liquid separation and condensation integrated device for hydrogen production by water electrolysis of claim 4, characterized in that, The horizontal separation section, vertical condensation section, and liquid collection section are an integrated shell structure, or can be combined into an integrated device through flange, welding, clamp, or threaded connection methods.

10. A working process of T-coupled gas-liquid separation and condensation integration for hydrogen production by electrolysis of water, characterized in that, The workflow is used in the apparatus of any one of claims 1-9, and the workflow includes: S1. The gas-liquid mixture generated during the electrolysis of water to produce hydrogen is fed into the device through the gas-liquid mixing inlet on the left side of the horizontal separation section; S2. The gas-liquid mixture generates swirling motion through the gas-liquid swirling internals set in the horizontal separation section, and achieves preliminary gas-liquid separation under the action of centrifugal force, inertia and gravity. S3. After initial liquid removal, the gas changes direction in the T-shaped junction area and enters the vertical condensation section vertically upward. S4. The gas exchanges heat with the condenser tube bundle located at the top of the vertical condensation section, causing the water vapor entrained in the gas to condense into liquid water. S5. Liquid water formed by the condensation of water vapor in the gas drips onto the liquid guiding structure located below the condenser tube bundle under the action of gravity. The liquid guiding structure receives the liquid and collects it along its liquid guiding surface. The liquid is then guided to the lower part of the vertical condensation section and flows into the liquid collection section, where it merges with the liquid obtained by cyclone separation. S6. The gas after condensation and dehumidification is passed through a wire mesh demister to remove residual droplets and then discharged from the upper gas phase outlet of the vertical condensation section. S7. The mixture of condensate and electrolyte in the collection section is returned to the electrolysis system via the return pipeline.

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