Hydrogen and natural gas mixing device

Abstract

The application discloses a hydrogen and natural gas mixing device, which comprises a mixer main pipeline, a first gas inlet is arranged on the mixer main pipeline, a connecting part is arranged on the mixer main pipeline, a second gas inlet pipe group is connected to the connecting part, a plurality of shunt through holes are arranged on the connecting part in the circumferential direction, the second gas inlet pipe group comprises an annular sleeve, the annular sleeve is sleeved on the connecting part, and a storage cavity in communication with the shunt through hole is arranged in the annular sleeve. The hydrogen and natural gas mixing device can improve the mixing rate of natural gas and hydrogen, expand the mixing area of the two, and ensure the mixing sufficiency and transmission fluency of natural gas and hydrogen without generating excessive interference factors in addition to the mixing of natural gas and hydrogen.

Description

Technical Field

[0001] This invention relates to the field of gas mixing technology, and more particularly to a gas mixing device for hydrogen and natural gas. Background Technology

[0002] Hydrogen energy is a green and clean secondary energy source that can drive energy transformation and deep decarbonization, with a wide range of applications, primarily in transportation, industry, energy storage, and construction. Among these, hydrogen gas turbines, as one of the main components of future new power systems, are a crucial pathway for the large-scale application of hydrogen energy, driving the development of the entire upstream, midstream, and downstream hydrogen energy industry chain. Currently, gas turbine power plants primarily use natural gas as fuel. As the fuel supply expands towards pure hydrogen, the combustion of hydrogen-natural gas mixtures in gas turbines is a significant research and development direction for gas turbine equipment.

[0003] For example, publication number "CN217367921U" discloses "a hydrogen-natural gas mixer," which includes a shell with openings at both ends. A hydrogen diffusion section is welded to the left edge of the opening, and a mixed gas contraction section is welded to the right edge of the opening. A hydrogen inlet flange is welded to the other end of the hydrogen diffusion section, and a mixed gas outlet flange is welded to the other end of the mixed gas contraction section. An opening for a natural gas connecting pipe to pass through is provided on the upper surface of the shell, and the connection between the natural gas connecting pipe and the opening is welded. A natural gas inlet flange is welded to the upper end of the natural gas connecting pipe, and a natural gas contraction section is welded to the lower end. A natural gas throat is welded to the other end of the natural gas contraction section, and a natural gas diffusion section is welded to the other end of the natural gas throat. An inner guide vane is welded to the opening of the natural gas diffusion section, and an outer guide vane is welded to the outer surface of the natural gas throat. However, in practical applications, due to the small mixing area of ​​natural gas and hydrogen, insufficient mixing can occur. Summary of the Invention

[0004] In view of the problem of insufficient reaction between natural gas and hydrogen in the prior art mentioned in the background, the present invention provides a mixing device for hydrogen and natural gas, which can improve the mixing rate of natural gas and hydrogen, expand the mixing area of ​​the two, and at the same time, without generating too many interference factors besides the mixing of natural gas and hydrogen, thus ensuring the sufficient mixing and smooth transmission of natural gas and hydrogen.

[0005] The second objective of this invention is to improve the uniformity of gas mixing.

[0006] To achieve the above objectives, the present invention adopts the following technical solution.

[0007] A hydrogen-natural gas mixing device includes a mixer main pipe with a first air inlet and a connecting part. A second air inlet pipe assembly is connected to the connecting part. The connecting part has a plurality of flow-diverting holes in the circumferential direction. The second air inlet pipe assembly includes an annular sleeve fitted onto the connecting part. A storage cavity communicating with the flow-diverting holes is provided inside the annular sleeve. The mixer's main pipeline is equipped with a first inlet and a second inlet pipe assembly. Hydrogen and natural gas can be supplied to the main pipeline from either the first inlet or the second inlet pipe assembly, respectively. The diameters of the first and second inlet pipe assemblies differ. The first inlet serves as the primary inlet, allowing a large volume flow of either hydrogen (hydrogen volume flow rate ratio greater than 50%) or natural gas (natural gas volume flow rate ratio greater than 50%) to be introduced. The selection of the appropriate inlet is adaptively determined based on the required gas mixture. A connecting section on the main pipeline connects to the second inlet pipe assembly and features flow-diverting holes to facilitate the transfer of gas supplied from the second inlet pipe assembly. The connecting section is part of the main pipeline's cylindrical wall. The multiple flow-diverting holes allow for more dispersed gas distribution within the main pipeline, improving the mixing quality of the hydrogen and natural gas. This also prevents the second inlet pipe assembly from directly penetrating the main pipeline and interfering with the gas mixing process. The system integrates gas delivery, and because the diversion orifices are located on the cylinder wall of the main mixer pipe, and the second inlet pipe assembly includes an annular sleeve and a storage cavity, the gas can fill the entire storage cavity. The diversion orifices, arranged circumferentially along the connection, enter the main mixer pipe from a 360° angle, mixing with the gas entering from the first inlet, thus increasing the mixing area. Furthermore, with the sum of the orifice areas of all diversion orifices being equal, the spacing between them is larger, reducing airflow interference and increasing the effective contact mixing area. The storage cavity allows the gas in the second inlet pipe assembly to be dispersed into each diversion orifice. Simultaneously, when the gas from the first inlet flows into the main mixer pipe, the flow velocity formed on the diversion orifices accelerates the entry of the gas from the storage cavity into the main mixer pipe. Since there is no structural interference between the second inlet pipe assembly and the main mixer pipe, the gas velocity in the mixer pipe assembly remains unaffected, ensuring uniform mixing and delivery.

[0008] Preferably, the second air intake pipe assembly includes a connecting pipe, one end of which is provided with a second air inlet, and the other end is connected to the storage cavity. The second air inlet is connected to an external air supply pipe. A flange is provided on the second air inlet for connection. A connecting pipe connects the second air inlet to the storage cavity. The connecting pipe is connected to an annular sleeve. During installation, the connection angle of the annular sleeve can be changed according to the pipeline layout requirements, thereby changing the orientation of the connecting pipe without affecting the arrangement of the main mixer pipeline. The relative position between the connecting pipe and the annular pipe can be perpendicular, tangential, or at an angle, depending on the installation requirements. A perpendicular connection between the connecting pipe and the annular sleeve ensures neatness of the arrangement. Furthermore, the connecting pipe can be offset circumferentially along the annular sleeve (i.e., at an angle). Preferably, the connecting pipe is tangentially connected to the annular sleeve, allowing the gas in the connecting pipe to fill the storage cavity more quickly and evenly along the guide of the annular sleeve, reducing kinetic energy loss and enabling more stable airflow delivery. This also prevents the gas in the connecting pipe from directly aligning with some of the flow distribution holes, which would cause uneven air intake in different areas of the storage cavity.

[0009] Preferably, a diffuser assembly capable of driving gas rotation and diversion is connected to the side of the connecting pipe near the diversion orifice. The diffuser assembly is rotatably connected inside the connecting pipe and includes several inclined diffuser channels. When the airflow passes through the diffuser channels, it drives the diffuser assembly to rotate. The diffuser assembly, with several diffuser channels, is located near the diversion orifice of the connecting pipe. This allows the gas transported in the connecting pipe to be delivered to various directions within the storage cavity through these channels, thereby quickly filling the storage cavity and ensuring uniform filling. Furthermore, because the diffuser channels are inclined, they generate a certain thrust when the airflow passes through, driving the diffuser assembly rotatably connected to the connecting pipe to rotate, thus producing a rotational acceleration effect. Preferably, the inlet diameter of the diffuser channel is larger than the outlet diameter, thereby accelerating the flow rate of the swirling gas. This solution achieves the second objective of the present invention.

[0010] Preferably, the annular sleeve is an oblique ring structure, with an angle α between its cross-section and the cross-section of the main mixer pipe. The oblique ring structure, where the cross-section of the annular sleeve is at an angle to the cross-section of the main mixer pipe, increases the span of the annular sleeve along the axis of the main mixer pipe. This allows the gas from the second intake pipe group to be introduced into the branch flow holes in different areas at different spans, lengthening the gas mixing path and making the mixing process smoother and more thorough. This avoids all the gas entering the main mixer pipe from the branch flow holes mixing in the same area, thus achieving the second objective of this invention.

[0011] Preferably, the intake pressure of the second intake port is greater than that of the first intake port. The diameter of the second intake port is smaller than that of the first intake port. Therefore, setting the intake pressure of the second intake port to be greater than that of the first intake port ensures that the gas in the second intake port can smoothly enter the main pipe of the mixer.

[0012] Preferably, the sum of the areas of all the branch flow holes is greater than the cross-sectional area of ​​the connecting pipe. Setting the sum of the areas of the branch flow holes to be greater than the cross-sectional area of ​​the connecting pipe avoids flow throttling and pressure reduction, ensuring that all gas in the connecting pipe can smoothly enter the main pipe of the mixer.

[0013] Preferably, the main mixer pipe is provided with a mixed gas outlet, and the main mixer pipe includes a baffle assembly disposed between the connection and the mixed gas outlet. The baffle assembly disposed at the connection and the mixed gas outlet can change the flow direction of the gas and achieve thorough mixing, and can also provide support for the main mixer pipe.

[0014] Preferably, the baffle assembly includes several baffle plate groups. Setting multiple baffle plate groups can maximize or decrease the mixed mass of the gas. The number of baffle plate groups can be increased or decreased based on the actual mixing ratio and simulation / experiment results. Different baffle plate groups are arranged at different angles, preferably at 90° angles, thereby improving the mixing effect of the baffle plate groups on the mixed gas.

[0015] Preferably, the baffle assembly is equipped with detection root valves at both ends. These detection root valves can be connected to external detection devices, such as differential pressure gauges. When impurities clog the pipe, the differential pressure gauge reading rises, alerting staff to promptly clean the pipes and ensure unobstructed flow.

[0016] Preferably, a drain valve is installed at the bottom of the main pipe of the mixer. This drain valve allows for the timely removal of sediment from the bottom of the main pipe during cleaning, improving cleaning efficiency.

[0017] The beneficial effects of this invention are as follows:

[0018] (1) By setting evenly distributed flow-diverting holes in the circumferential direction of the connecting part and communicating with the storage cavity, the gas in the second air inlet can enter the main pipe of the mixer evenly from all directions of the connecting part, and the reaction area is increased, and the interference of airflow between the various flow-diverting holes is reduced.

[0019] (2) There are no other interference factors between the second air intake pipe group and the main pipe of the mixer except for the mixing of gases, which makes the overall structure simple, reduces pressure loss, and ensures smooth airflow inside the main pipe of the mixer.

[0020] (3) Setting the connecting pipe to be tangent to the annular sleeve and setting the diffuser assembly can make the gas entering the second air inlet fill the storage cavity faster and more evenly, ensuring the uniformity of the airflow in each diversion hole.

[0021] (4) The annular sleeve is set into a slanted ring shape, so that the annular sleeve occupies a longer span on the main pipe of the mixer, thereby allowing the flow holes in different areas to mix at different spans, making the entire mixing process smoother and more thorough, while reducing interference. Attached Figure Description

[0022] Figure 1 This is an isometric view of the present invention.

[0023] Figure 2 This is an exploded view of the present invention.

[0024] Figure 3 This is a schematic diagram of the structure of the present invention.

[0025] Figure 4 This is a schematic diagram of the structure of Example 2.

[0026] Figure 5 This is a schematic diagram of the structure of Example 3.

[0027] Figure 6 yes Figure 5 Axonometric view of the diffuser assembly.

[0028] Figure 7 yes Figure 5 Cross-sectional view of the diffuser assembly.

[0029] Figure 8 This is a structural schematic diagram of Example 4.

[0030] In the diagram: 1. Mixer main pipe, 11. First air inlet, 12. Connecting part, 13. Diverting flow hole, 14. Mixed gas outlet, 2. Second air inlet pipe assembly, 21. Annular sleeve, 22. Flow storage cavity, 23. Connecting pipe, 24. Second air inlet, 3. Diffuser assembly, 31. Diffuser channel, 4. Baffle assembly, 41. Baffle plate assembly, 5. Detection root valve, 6. Drain valve. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0032] Example 1:

[0033] like Figure 1 , 2As shown in Figure 3, a hydrogen and natural gas mixing device includes a mixer main pipe 1, a first air inlet 11 on the mixer main pipe 1, a connecting part 12 on the mixer main pipe 1, a second air inlet pipe group 2 connected to the connecting part 12, and evenly distributed flow-diverting holes 13 in the circumferential direction of the connecting part 12. The second air inlet pipe group 2 includes an annular sleeve 21, which is sleeved on the connecting part 12. A storage cavity 22 communicating with the flow-diverting holes 13 is provided inside the annular sleeve 21. The air inlet pressure of the second air inlet 24 is greater than the air inlet pressure of the first air inlet 11.

[0034] A first air inlet 11 and a second air inlet pipe group 2 are provided on the main pipe 1 of the mixer. In this embodiment, hydrogen is transported from inside the second air inlet pipe group 2 into the main pipe 1 of the mixer, while natural gas is input from the first air inlet 11. A connecting part 12 is provided on the main pipe 1 of the mixer and connects to the second air inlet pipe group 2. The connecting part 12 is provided with a flow diversion hole 13, which can transmit the gas transported in the second air inlet pipe group 2. The connecting part 12 is part of the cylinder wall of the main pipe 1 of the mixer, and the arrangement of multiple flow diversion holes 13 can make the gas in the second air inlet pipe group 2 more distributed. The gas enters the main pipe 1 of the mixer in a dispersed manner, improving the mixing quality of hydrogen and natural gas. This also prevents the second inlet pipe group 2 from directly penetrating the main pipe 1 and interfering with gas mixing and transport within the main pipe 1. Furthermore, because the diversion orifice 13 is located on the wall of the main pipe 1, and the second inlet pipe group 2 includes an annular sleeve 21 and a storage cavity 22, gas can fill the entire storage cavity 22. The diversion orifice 13, arranged along the circumferential direction of the connection portion 12, allows gas to enter the main pipe 1, improving the mixing quality of hydrogen and natural gas. This also prevents the second inlet pipe group 2 from directly penetrating the main pipe 1 and interfering with gas mixing and transport within the main pipe 1. The gas enters the main pipe 1 of the mixer in a 360° direction and mixes with the gas entering through the first inlet 11, thereby increasing the mixing area. Furthermore, with the sum of the areas of all the branch flow holes 13 being equal, the spacing between the branch flow holes 13 in this design is larger, reducing interference between airflows and resulting in a larger effective contact mixing area. The storage cavity 22 allows the gas in the second inlet pipe group 2 to be dispersed into each branch flow hole 13. Simultaneously, when the gas flows into the main pipe 1 of the mixer from the first inlet 11, it is distributed... The flow velocity formed on the through hole 13 will accelerate the entry of the gas inside the storage cavity 22 into the mixer main pipe 1. Since there is no structural interference between the second air inlet pipe group 2 and the mixer main pipe 1, the flow velocity of the gas in the mixer pipe group is not affected at all points, and it can be mixed and transported evenly. The diameter of the second air inlet 24 is smaller than the diameter of the first air inlet 11. Therefore, the air inlet pressure of the second air inlet 24 is set to be greater than the air inlet pressure of the first air inlet 11, ensuring that the gas in the second air inlet 24 can smoothly enter the mixer main pipe 1.

[0035] like Figure 3As shown, the second air intake pipe group 2 includes a connecting pipe 23. One end of the connecting pipe 23 is provided with a second air inlet 24, and the other end is connected to the storage cavity 22. The sum of the areas of each diversion flow hole 13 is greater than the cross-sectional area of ​​the connecting pipe 23.

[0036] The second air inlet 24 is connected to an external gas supply pipe. A flange for connection is provided on the second air inlet 24. The connecting pipe 23 connects the second air inlet 24 to the storage cavity 22. The connecting pipe 23 can be vertically connected to the annular sleeve 21 to ensure the neatness of the arrangement. The sum of the areas of the diversion holes 13 is greater than the cross-sectional area of ​​the connecting pipe 23 to avoid flow throttling and pressure reduction, and to ensure that the gas in the connecting pipe 23 can smoothly enter the main pipeline 1 of the mixer.

[0037] like Figure 1 , 3 As shown, the main pipe 1 of the mixer is provided with a mixed gas outlet 14. The main pipe 1 of the mixer includes a baffle assembly 4 disposed between the connection part 12 and the mixed gas outlet 14. The baffle assembly 4 includes two baffle plate groups 41 arranged at a 90° angle.

[0038] The baffle assembly 4 provided on the connection part 12 and the mixed gas outlet 14 can change the flow direction of the gas and make it fully mixed. It can also support the main pipe 1 of the mixer. The multiple baffle groups 41 can maximize the mixing quality of the gas. The baffle groups 41 can be increased or decreased according to the actual mixing ratio and simulation and experimental results.

[0039] like Figure 1 , 2 As shown, detection root valves 5 are installed at both ends of the baffle assembly 4. The detection root valves 5 are connected to differential pressure gauges. When impurities clog the pipe, the differential pressure gauge reading rises, thus alerting staff to clean the pipes promptly and ensuring unobstructed flow.

[0040] like Figure 1 , 2 As shown, a drain valve 6 is installed at the bottom of the main pipe 1 of the mixer. The drain valve 6 allows for the timely removal of sediment from the bottom of the main pipe 1 during cleaning, thus improving cleaning efficiency.

[0041] The assembly and operation of the hydrogen and natural gas mixing device in this embodiment are as follows: In this embodiment, the hydrogen volumetric flow rate ratio is less than 50%, so hydrogen is transported from the second inlet 24, while natural gas is transported from the first inlet 11. The second inlet pipe assembly 2 includes an annular sleeve 21, which is sleeved on the connecting part 12. Multiple diversion holes 13 are evenly distributed circumferentially on the connecting part 12, and the diversion holes 13 communicate with the storage cavity 22 in the annular sleeve 21. In this embodiment, the connecting pipe 23 is perpendicular to the annular sleeve 21 and is located at the first inlet. Flanges are connected to both the connection 11 and the second inlet 24. A baffle assembly 4 is provided between the connection 12 and the mixed gas outlet 14. The baffle assembly 4 includes two baffle plate groups 41. Detection root valves 5 are connected to both ends of the baffle assembly 4. The detection root valves 5 are connected to differential pressure gauges. A drain valve 6 is provided at the bottom of the main pipeline 1 of the mixer. During operation, hydrogen is introduced from the second inlet 24 and natural gas is introduced from the first inlet 11. The mixture is completed in the pipeline corresponding to the connection 12 and then fully mixed again in the baffle assembly 4, thereby improving the mixing quality.

[0042] Example 2:

[0043] like Figure 4 As shown, unlike Embodiment 1, in this embodiment, the connecting pipe 23 is tangentially connected to the annular sleeve 21, which allows the gas in the connecting pipe 23 to fill the storage cavity 22 more quickly and evenly along the guide of the annular sleeve 21, reducing kinetic energy loss and enabling the airflow to be delivered more smoothly. It also prevents the gas in the connecting pipe 23 from directly aligning with some of the diversion holes 13, which would result in uneven air intake of the diversion holes 13 in different areas of the storage cavity 22.

[0044] Example 3:

[0045] like Figure 5 , 6As shown in Figure 7, unlike in Embodiment 1, in this embodiment, the connecting pipe 23 is connected to a diffuser assembly 3 that can drive the gas to rotate and divert. The diffuser assembly 3 is rotatably connected inside the connecting pipe 23. The diffuser assembly 3 includes diffuser channels 31 arranged in a ring at an angle. The opening of the diffuser channel 31 is perpendicular to the connecting pipe 23. When the airflow passes through the diffuser channel 31, it drives the diffuser assembly 3 to rotate. A diffuser assembly 3 is provided on the side of the connecting pipe 23 near the diversion orifice 13. The diffuser assembly 3 is provided with multiple diffuser channels 31 arranged in a ring. It can deliver the gas transported in the connecting pipe 23 to various directions in the storage cavity 22 through the diffuser channels 31, thereby quickly filling the storage cavity 22 and ensuring uniform filling of the airflow in the storage cavity 22. At the same time, since the diffuser channels 31 are inclined, they can generate a certain thrust when the airflow passes through, thereby driving the diffuser assembly 3 rotatably connected to the connecting pipe 23 to rotate, thereby producing a rotational acceleration effect. Preferably, the inlet diameter of the diffuser channel 31 is larger than the outlet diameter, thereby accelerating the flow rate of the swirling gas. Example 4:

[0046] like Figure 8 As shown, unlike Embodiment 1, in this embodiment the annular sleeve 21 is a slanted ring structure, and there is an angle α between the cross-section of the annular sleeve 21 and the cross-section of the main pipe 1 of the mixer. The second air inlet pipe group 2 is located on the side of the annular sleeve 21 near the first air inlet 11. The annular sleeve 21 is configured as an oblique ring structure, meaning that there is an angle between the cross-section of the annular sleeve 21 and the cross-section of the main mixing pipe 1. This results in a longer span of the annular sleeve 21 along the axis of the main mixing pipe 1, allowing the gas from the second intake pipe group 2 to be input into different areas of the branch flow holes 13 at different spans. This lengthens the gas mixing path, making the mixing process more stable and thorough. It also prevents all the gas entering the main mixing pipe 1 from the branch flow holes 13 from mixing in the same area. When the connecting pipe is set perpendicular to the annular sleeve, more gas flows through the branch flow holes closer to the connecting pipe. Since the second intake pipe group is set closer to the first intake port, the gas flowing through the branch flow holes in the area aligned with the connecting pipe has more subsequent mixing strokes in the main mixing pipe, ensuring thorough mixing.

Claims

1. A hydrogen and natural gas mixing device, characterized by, The mixer main pipeline is provided with a first air inlet, and the mixer main pipeline is provided with a connecting portion, and the connecting portion is connected with a second air inlet pipe group, and a plurality of shunt through holes are arranged in the circumferential direction of the connecting portion, and the second air inlet pipe group comprises an annular sleeve, the annular sleeve is sleeved on the connecting portion, and a flow storage cavity in communication with the shunt through holes is arranged in the annular sleeve; the second air inlet pipe group comprises a connecting pipe, one end of the connecting pipe is provided with a second air inlet, and the other end of the connecting pipe is in communication with the flow storage cavity; the side of the connecting pipe close to the shunt through holes is connected with a flow distribution assembly capable of driving the gas to rotate and shunt, the flow distribution assembly is rotationally connected in the connecting pipe, the flow distribution assembly comprises a plurality of inclined flow distribution channels, and the flow distribution assembly is driven to rotate when the gas flows through the flow distribution channels; the annular sleeve is a slanted ring structure.

2. The hydrogen-natural gas mixing device according to claim 1, wherein An included angle α exists between the cross section of the annular sleeve and the cross section of the mixer main pipeline.

3. The hydrogen-natural gas mixing device according to one of claims 1, wherein The air inlet pressure of the second air inlet is greater than the air inlet pressure of the first air inlet.

4. The hydrogen-natural gas mixing device according to one of claims 1, wherein The sum of the areas of the shunt through holes is greater than the cross-sectional area of the connecting pipe.

5. The hydrogen-natural gas mixing device according to one of claims 1, wherein The mixer main pipeline is provided with a mixed gas outlet, and the mixer main pipeline comprises a baffle assembly arranged between the connecting portion and the mixed gas outlet.

6. The hydrogen-natural gas mixing device according to one of claims 5, wherein The baffle assembly comprises a plurality of baffle plates.

7. The hydrogen-natural gas mixing device according to one of claims 5 or 6, characterized in that, Detection roots are arranged at both ends of the baffle assembly.

8. The hydrogen-natural gas mixing device according to one of claims 1, wherein A blowdown valve is arranged at the bottom of the mixer main pipeline.

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