Pre-separation device of electrolytic hydrogen production system based on gravity separation principle

Abstract

The utility model discloses a pre-separation device of an electrolytic hydrogen production system based on a gravity separation principle, which comprises an electrolytic bath and a gas-liquid separator, the pre-separator is arranged on a material pipeline of the electrolytic bath entering the gas-liquid separator, a mixture inlet and a liquid outlet are arranged at the lower part of the pre-separator, and a gas outlet is arranged at the top of the pre-separator. The mixture inlet is connected with the outlet end of the electrolytic cell through a material pipeline, the liquid outlet is connected to a liquid phase in the gas-liquid separator through a liquid pipeline, and the gas outlet is connected to a top gas phase of the gas-liquid separator through a gas pipeline. According to the utility model, the pre-separator is innovatively and additionally arranged. According to the gravity separation principle, a vertical cylindrical shell is adopted. By means of the layout, gas and liquid can be preliminarily separated within a very short time, the workload of a subsequent gas-liquid separator is greatly relieved, the overall separation efficiency is remarkably improved, and a solid foundation is laid for efficient operation of the whole electrolytic hydrogen production process.

Description

TECHNICAL FIELD

[0001] The utility model relates to gas -liquid separation technical field, concretely relates to a kind of pre-separation device of electrolytic hydrogen production system based on gravity separation principle. BACKGROUND

[0002] In electrolytic hydrogen production device system, gas-liquid separation system plays an important role in separating gas and liquid, specifically, gas-liquid separation system is the gas-liquid mixture from electrolytic cell hydrogen or oxygen and lye is carried out gas-liquid separation.In hydrogen branch, it mainly includes hydrogen separator, hydrogen scrubber, hydrogen cooler, in oxygen branch, it mainly includes oxygen separator, oxygen scrubber, oxygen cooler;And lye cooler, lye filter (one open one spare), lye circulating pump (one open one spare), water supply pump, instrument, valve, pipeline, pipe fitting, frame etc.;Gas-liquid separation system control cabinet is the core of control part, can realize automatic regulation, display, alarm, interlocking function, ensure the safe and stable operation of electrolytic cell and gas-liquid separation system.

[0003] Take hydrogen side gas-liquid separation as an example, oxygen side gas-liquid separation process is basically the same, and is not described repeatedly.Hydrogen and lye gas-liquid mixture from electrolytic cell are carried out gas-liquid separation together through the gas outlet hole of cathode side of pole frame and flow through hydrogen flow channel, flow out from negative pole frame, gather and then enter hydrogen separator, and preliminary gas-liquid separation is carried out under the action of gravity settling, and hydrogen and lye are separated.

[0004] In prior art, gas and liquid from electrolytic cell directly enter gas-liquid separator and carry out gas-liquid separation, such as application number: CN202211558391.X energy-saving and environment-friendly electrolytic hydrogen production system and electrolytic hydrogen production method, which includes: cooler, high tank, raw water conveying equipment, electrolytic cell, oxygen circulating pump, oxygen liquid separator, hydrogen circulating pump, hydrogen liquid separator;The anode outlet and cathode outlet of electrolytic cell are directly connected to corresponding oxygen liquid separator and hydrogen liquid separator.Such that the load of gas-liquid separator is large, thereby greatly affecting gas-liquid separation effect, making the working efficiency of entire hydrogen production system low, leading to long separation time and the risk of incomplete separation.Gas phase and liquid phase have great difference in flow characteristics and physical properties, and if gas-liquid mixture directly enters downstream pipeline and equipment, it can cause damage to equipment, especially the mixed two-phase flow of oxygen and lye, which is extremely serious in scouring and corrosion of pipeline.

[0005] In view of the above, it is necessary to provide a pre-separation device of electrolytic hydrogen production system based on gravity separation principle to solve the above problems. UTILITY MODEL CONTENTS

[0006] The utility model aims at overcoming the defects in prior art, and provides a pre-separation device of electrolytic hydrogen production system based on gravity separation principle.

[0007] In order to achieve the above object, the technical scheme of the utility model is as follows: a pre-separation device of an electrolytic hydrogen production system based on gravity separation principle, including electrolytic cell, gas-liquid separator, pre-separator is arranged on the material pipeline of electrolytic cell into gas-liquid separator, the pre-separator has vertically arranged cylindrical shell, the lower part of pre-separator is equipped with mixed material inlet, liquid outlet, the top of pre-separator is equipped with gas outlet, the mixed material inlet is connected with the outlet end of electrolytic cell through material pipeline, the liquid outlet is connected to the liquid phase in gas-liquid separator through liquid pipeline, and the gas outlet is connected to the top gas phase of gas-liquid separator through gas pipeline.

[0008] Further, the mixed material inlet and the liquid outlet of the pre-separator are arranged on the two sides of the pre-separator respectively.

[0009] Further, the mixed material inlet is provided with at least one, when multiple mixed material inlets are arranged, they can be arranged from low to high in turn, and each mixed material inlet is connected to each outlet end of the electrolytic cell in turn.

[0010] Further, the cylindrical shell is cylindrical, and the ratio of the height to the diameter of the cylindrical shell is 15-25:1.

[0011] Further, the lower part of the cylindrical shell is provided with spiral guide vanes, so that the gas-liquid mixture forms a cyclone centrifugal motion in the cylindrical shell under the guidance of the guide vanes.

[0012] Further, the surface of the guide vane is covered with a nano-liquid-repellent coating that accelerates the aggregation of liquid droplets, and the nano-liquid-repellent coating makes the contact angle of the liquid droplets greater than 150°.

[0013] Further, the middle part of the cylindrical shell is provided with a tapered expansion cavity.

[0014] Further, an ultrasonic wave array module for breaking up entrained liquid droplets is mounted on the inner wall of the expansion cavity, and the ultrasonic wave array module emits high-frequency vibration waves with a vibration frequency of 20-40 kHz.

[0015] Further, the top of the cylindrical shell is provided with a honeycomb-shaped flow regulator, and the upper side of the honeycomb-shaped flow regulator is provided with an electrostatic precipitation module.

[0016] Further, the honeycomb-shaped flow regulator is made of titanium alloy material, and has a pore diameter of 1-3 mm and a thickness of 50-150 mm; the voltage of the electrostatic precipitation module is 5kv, and the interelectrode distance is 10mm.

[0017] The utility model has the advantages and beneficial effects that:

[0018] 1. In the material conveying pipeline of the electrolytic cell leading to the gas-liquid separator, a pre-separator is innovatively added. The pre-separator skillfully uses the principle of gravity separation and realizes efficient work with a unique and ingenious structure design. It adopts a vertical cylindrical shell, with a mixed material inlet and a liquid outlet precisely set at the lower part, and a gas outlet at the top. This layout can preliminarily separate gas and liquid in a very short time, greatly reducing the work burden of the subsequent gas-liquid separator, significantly improving the overall separation efficiency, and laying a solid foundation for the efficient operation of the entire electrolytic hydrogen production process.

[0019] 2. The cylindrical shell adopts a cylindrical design, with the height-to-diameter ratio controlled between 15-25:1. This carefully planned slender structure effectively prolongs the residence time of gas and liquid in the shell, making the gas-liquid separation process more complete and thorough. At the same time, spiral flow guides are set at the lower part of the shell to induce the gas-liquid mixture to form a cyclone centrifugal motion, further significantly enhancing the gas-liquid separation effect, and double-protecting the efficiency of separation from both physical structure and motion principle.

[0020] 3. A conical expansion cavity is set in the middle of the pre-separator, which effectively slows down the gas-liquid flow rate and creates favorable conditions for further separation of gas and liquid. The ultrasonic array module installed on the inner wall of the cavity emits high-frequency vibration waves with a frequency of 20-40 kHz during operation, which can accurately break the entrained droplets, making the produced gas more pure. At the top of the shell, a honeycomb-shaped flow straightener made of titanium alloy is equipped, with a pore size of 1-3mm and a thickness of 50-150mm, which can effectively regulate the gas flow; the electrostatic precipitation module works in coordination, with a voltage setting of 5kv and an inter-electrode distance of 10mm, which can capture micron-sized droplets, efficiently remove small liquid mist, and further improve the purity of the gas, ensuring the high-quality production of hydrogen. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a process schematic diagram of a pre-separation device of an electrolytic hydrogen production system based on the principle of gravity separation according to the present application;

[0022] Figure 2 is a schematic diagram of the external structure of the pre-separator in embodiment one of the present application;

[0023] Figure 3 is a schematic diagram of the structure with flow guides set at the lower side inside the pre-separator in the present application;

[0024] Figure 4 is an exploded view of the pre-separator with flow guides in the present application;

[0025] Figure 5 is a schematic diagram of the structure with an expansion cavity set in the pre-separator structure in the present application;

[0026] In the diagram: 1. Electrolytic cell; 2. Gas-liquid separator; 3. Material pipeline; 4. Pre-separator; 5. Cylindrical shell; 6. Mixture inlet; 7. Liquid outlet; 8. Gas outlet; 9. Outlet end; 10. Liquid pipeline; 11. Gas pipeline; 12. Flow guide plate; 13. Expansion cavity; 14. Ultrasonic array module; 15. Honeycomb rectifier; 16. Electrostatic demister module. Detailed Implementation

[0027] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0028] Implementation 1:

[0029] A pre-separation device for an electrolytic hydrogen production system based on gravity separation includes an electrolytic cell 1 and a gas-liquid separator 2. A pre-separator 4 is installed on the material pipeline 3 from the electrolytic cell 1 to the gas-liquid separator 2. The pre-separator 4 has a vertically arranged cylindrical shell 5, which is cylindrical with a height-to-diameter ratio of 15-25:1. After the gas-liquid mixture enters the pre-separator 4 through the mixture inlet 6, due to gravity, the denser liquid flows downwards, while the less dense hydrogen and oxygen mixture moves upwards. Inside the pre-separator 4, the gas-liquid separation process is not a simple natural sedimentation but is accelerated based on the principles of gravity separation and fluid mechanics, thereby improving the gas-liquid separation efficiency.

[0030] In practical applications, pre-separators 4 can be installed separately in the hydrogen and oxygen branches of the electrolytic hydrogen production system, such as... Figure 1 As shown, the electrolytic cell 1 has two branches: an oxygen branch on the upper side and a hydrogen branch on the lower side. The material in the oxygen branch is a gas-liquid mixture of oxygen and alkali, while the material in the hydrogen branch is a mixture of hydrogen and alkali. The two materials enter the corresponding pre-separators 4 for separation. In this embodiment, the pre-separator 4, which is set between the electrolytic cell 1 and the gas-liquid separator 2, reduces the load on the gas-liquid separator 2 and effectively improves the gas-liquid separation effect. In this embodiment, a cylindrical shell 5 with a large length-to-diameter ratio is used, which greatly increases the material residence time and promotes gas-liquid separation. Utilizing the principle of gravity separation, the alkali and gas are separated from each other, and the separated materials are connected and sent to different positions of the gas-liquid separator 2, resulting in a good pre-separation effect.

[0031] Specifically, in this embodiment, the gas-liquid separator 2 in the hydrogen branch has a diameter of 325 mm and a height of 6500 mm; at the same time, the gas-liquid separator 2 in the oxygen branch has a diameter of 275 mm and a height of 6500 mm.

[0032] like Figure 2 As shown, the pre-separator 4 is provided with a mixture inlet 6 and a liquid outlet 7 at the bottom, and a gas outlet 8 at the top. The mixture inlet 6 is connected to the outlet end 9 of the electrolytic cell 1 through the material pipeline 3. The liquid outlet 7 is connected to the liquid phase inside the gas-liquid separator 2 through the liquid pipeline 10. The gas outlet 8 is connected to the gas phase at the top of the gas-liquid separator 2 through the gas pipeline 11.

[0033] The mixture inlet 6 and liquid outlet 7 of the pre-separator 4 are respectively located on both sides of the pre-separator 4, and preferably, as shown below. Figure 2 As shown, the position of the mixture inlet 6 is higher than that of the liquid outlet 7. There is at least one mixture inlet 6; when multiple mixture inlets 6 are provided, they are arranged sequentially from low to high, and each mixture inlet 6 is sequentially connected to a corresponding outlet 9 of the electrolytic cell 1. It can be understood that the number of mixture inlets 6 is set according to the number of outlets 9 of the electrolytic cell 1. This number can be increased or decreased according to actual conditions, and the number is not limited. This embodiment uses three inlets as an example.

[0034] Example 2:

[0035] Furthermore, in accordance with the technology of Embodiment 1, the lower part of the cylindrical shell 5 is provided with a spiral guide vane 12, so that the gas-liquid mixture forms a swirling centrifugal motion inside the cylindrical shell 5 under the guidance of the guide vane 12. Specifically, as shown... Figure 3 , 4 As shown, a spiral guide vane 12 is provided on the lower inner side of the cylindrical shell 5. The guide vane 12 is a double spiral vane 12, with an inward 45° inclination angle and staggered arrangement. This forces the gas-liquid mixture to form a swirling centrifugal motion within the cylindrical shell 5, thereby achieving centrifugal separation. The heavier liquid adheres to the wall and rotates downwards, while the lighter gas gathers and rises in the middle. In this embodiment, the feed direction of the mixture inlet 6 is preferably along the tangential direction of the cylindrical shell 5. After the gas-liquid mixture enters tangentially, the liquid rotates and falls downwards due to the collision and guidance with the guide vane 12 and the inner wall of the cylindrical shell 5, thus enhancing the separation effect of gas and liquid using the principle of centrifugal separation. Furthermore, the feed position of the mixing inlet is at the interval between the two guide vanes 12.

[0036] Further, the surface of the guide vane 12 is covered with a nano-liquid-repellent coating that accelerates the aggregation of liquid droplets, and the nano-liquid-repellent coating makes the contact angle of the liquid droplets greater than 150°. In actual use, the nano-liquid-repellent coating can be a fluoropolymer, such as a nano-liquid-repellent coating material perfluoropolyether, etc. Fluorine atoms have high electronegativity and small atomic radius, etc., so that the surface energy of fluoropolymers is extremely low, and they have excellent hydrophobic and oleophobic properties. It can also be an inorganic nanomaterial, such as silica, alumina, etc. Inorganic nanoparticles are often used to prepare nano-liquid-repellent coatings. These inorganic nanoparticles can form a nanoscale rough structure on the surface of an object through sol-gel processes, etc., and then combined with surface modification treatment to make them liquid-repellent.

[0037] After the liquid rotates and falls to the bottom, it flows out through the liquid outlet 7. An adjustable vortex suppression baffle is arranged at the inner bottom, and the opening degree is adjusted through an external handle to control the stability of the liquid flow at the bottom.

[0038] Example Three:

[0039] Further, as shown in Figure 5 The middle part of the cylindrical shell 5 is provided with a tapered expansion cavity part 13. The flow rate is reduced by the sudden change in cross-sectional area, and secondary separation is achieved by using the inertial effect. When the rising gas reaches the expansion cavity part 13, the speed decreases significantly, thereby giving the liquid droplets entrained in the gas time to fall. Further, an ultrasonic array module 14 for breaking up entrained liquid droplets is mounted on the inner wall of the expansion cavity part 13. The ultrasonic array module 14 emits high-frequency vibration waves with a vibration frequency of 20-40 kHz. When the gas rises, the ultrasonic array module 14 can break the bubbles, avoiding the formation of foam in the cylindrical shell 5. The high-frequency vibration of the ultrasonic waves can break the bubbles on the surface of the liquid, causing them to rupture and release to the surface of the liquid, thereby achieving the effect of defoaming. The focusing property of the ultrasonic waves produces high energy in a specific area, which also facilitates the decomposition of aggregated bubbles. The ultrasonic array module is different from the chemical defoaming method in the prior art, as it does not require the addition of chemical reagents, thereby avoiding the contamination of the separated alkali liquor and facilitating the recycling of the alkali liquor. The ultrasonic array module 14 can achieve good defoaming effect, thereby avoiding the entrainment of liquid droplets in the rising gas flow.

[0040] Further, the top of the cylindrical shell 5 is provided with a honeycomb flow regulator 15, and the upper side of the honeycomb flow regulator 15 is provided with an electrostatic demisting module 16. The honeycomb flow regulator 15 can inhibit the turbulent flow of the gas and adsorb the liquid film, and the electrostatic demisting module 16 can capture micrometer-sized liquid droplets, thereby enhancing the gas-liquid separation effect. The function of the flow regulator 15 is to make the gas flow more smoothly and reduce the turbulent flow of the gas, and the function of the electrostatic demisting module 16 is to capture small liquid droplets and make the gas-liquid separation effect better. The electrostatic demisting is to use the adsorption effect of static electricity to adsorb small liquid droplets on the surface of the module, thereby reducing the liquid-carrying gas flow. The honeycomb flow regulator 15 is composed of many hexagonal micropores, which can promote the full flow of the gas, reduce the resistance, and help the liquid to be carried to the demisting module. Specifically, the honeycomb flow regulator 15 is made of titanium alloy material, which has good corrosion resistance, and the pore size is 1-3mm and the thickness is 50-150mm; the voltage of the electrostatic demisting module 16 is 5kv, and the interelectrode distance is 10mm.

[0041] The specific process control method of the system is:

[0042] 1. Ultrasonic-electrostatic cooperative demisting strategy, through parameter linkage control, specifically, when the gas phase moisture content monitoring value > 5%: start the ultrasonic atomizer (power density 0.5W / cm²), break the internal formed bubbles or floating foam. Synchronously improve the electrostatic module voltage to 7kV, enhance the electric field adsorption force. Safety protection: when the moisture content > 10%, trigger the emergency discharge program, the outlet valve is closed, and the liquid is directly discharged to the main separator through the bypass.

[0043] 2. Liquid level-flow coupling adjustment, through the liquid level meter to collect the bottom liquid level data (target value: 300±10mm) in real time. Calculate the valve opening correction amount through the PID algorithm. Output 4-20mA signal to drive the proportional valve; establish a suitable liquid level in the bottom of the cylindrical shell 5.

[0044] The system is provided with a three-stage separation module of a spiral centrifugal layer + a conical expansion cavity part 13 + a honeycomb flow regulating layer in the pre-separator 4, which breaks through the traditional single gravity separation mode, adds centrifugal separation, ultrasonic demisting, and electrostatic demisting module 16, so that the system can maintain a high separation effect.

[0045] The above is only the preferred embodiment of the present application, and it should be pointed out that for ordinary skilled persons in the technical field, without departing from the technical principles of the present application, some improvements and refinements can be made, and these improvements and refinements should be regarded as the protection scope of the present application.

Claims

1. A pre-separation device for an electrolytic hydrogen production system based on the principle of gravity separation, comprising an electrolytic cell (1) and a gas-liquid separator (2), characterized in that, A pre-separator (4) is installed on the material pipeline (3) from the electrolytic cell (1) to the gas-liquid separator (2). The pre-separator (4) has a cylindrical shell (5) arranged vertically. The lower part of the pre-separator (4) is provided with a mixture inlet (6) and a liquid outlet (7). The top of the pre-separator (4) is provided with a gas outlet (8). The mixture inlet (6) is connected to the outlet end (9) of the electrolytic cell (1) through the material pipeline (3). The liquid outlet (7) is connected to the liquid phase inside the gas-liquid separator (2) through a liquid pipeline (10). The gas outlet (8) is connected to the top gas phase of the gas-liquid separator (2) through a gas pipeline (11). The lower part of the cylindrical shell (5) is provided with a spiral guide vane (12), so that the gas-liquid mixture forms a swirling centrifugal motion inside the cylindrical shell (5) under the guidance of the guide vane (12).

2. The pre-separation device for an electrolytic hydrogen production system based on the principle of gravity separation according to claim 1, characterized in that, The mixture inlet (6) and liquid outlet (7) of the pre-separator (4) are respectively located on both sides of the pre-separator (4).

3. The pre-separation device for an electrolytic hydrogen production system based on the principle of gravity separation according to claim 2, characterized in that, The mixture inlet (6) is provided with at least one, and each mixture inlet (6) is sequentially connected to each outlet end (9) of the electrolytic cell (1).

4. The pre-separation device for an electrolytic hydrogen production system based on the principle of gravity separation according to claim 3, characterized in that, The cylindrical shell (5) is cylindrical, and the ratio of the height to the diameter of the cylindrical shell (5) is 15~25:

1.

5. The pre-separation device for an electrolytic hydrogen production system based on the principle of gravity separation according to claim 1, characterized in that, The surface of the guide plate (12) is covered with a nano-hydrophobic coating that accelerates droplet aggregation, and the nano-hydrophobic coating makes the contact angle of the droplets greater than 150°.

6. The pre-separation device for an electrolytic hydrogen production system based on the principle of gravity separation according to claim 1, characterized in that, The cylindrical shell (5) has a conical expansion cavity (13) in the middle.

7. The pre-separation device for an electrolytic hydrogen production system based on the principle of gravity separation according to claim 6, characterized in that, The inner wall of the expansion cavity (13) is equipped with an ultrasonic array module (14) for breaking up entrained droplets. The ultrasonic array module (14) emits high-frequency vibration waves with a vibration frequency of 20-40kHz.

8. The pre-separation device for an electrolytic hydrogen production system based on the principle of gravity separation according to claim 1, characterized in that, The top of the cylindrical shell (5) is provided with a honeycomb rectifier (15), and the upper side of the honeycomb rectifier (15) is provided with an electrostatic defoaming module (16).

9. The pre-separation device for an electrolytic hydrogen production system based on the principle of gravity separation according to claim 8, characterized in that, The honeycomb rectifier (15) is made of titanium alloy with a pore size of 1-3 mm and a thickness of 50-150 mm; the electrostatic defogging module (16) has a voltage of 5 kV and an electrode spacing of 10 mm.

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