Hydrogen-doped mixed combustion system provided with hydrogen distribution component

Abstract

The invention relates to a hydrogen-doped mixed combustion system provided with a hydrogen distribution component, which is characterized in that a hydrogen pipeline and a main pipeline are vertically arranged, the hydrogen pipeline is arranged between a natural gas box body and a combustor, the hydrogen pipeline and the main pipeline are vertically connected, and the connecting position of the hydrogen pipeline and the main pipeline is arranged between the natural gas box body and the combustor. The hydrogen pipeline is horizontally arranged, a hydrogen flow equalizing device is arranged in the hydrogen pipeline, the hydrogen distribution component is of a blade structure, the blade structure comprises a plurality of blades, a flow channel between every two adjacent blades is in the horizontal direction, and the flow area of the flow channel between every two adjacent blades is continuously reduced in the vertical direction from bottom to top. According to the combustor of the hydrogen distribution component, the gaps of the blades of the hydrogen distribution component are arranged, so that hydrogen can be uniformly distributed, different proportions of local natural gas and hydrogen can be avoided, the combustion efficiency can be improved, and accidents can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of combustion technology, and in particular to a hydrogen-blended mixed combustion system provided with a hydrogen distribution component. Background Art

[0002] With the continuous advancement of carbon emission reduction policies worldwide, hydrogen, a high-energy-density gas fuel and a green, clean, and efficient new energy storage medium that does not directly produce pollutants such as carbon compounds, sulfur oxides, and soot during its direct use, is considered one of the most promising clean energy sources. China has officially included hydrogen energy in its energy category and is continuously promoting the development of related industries. The booming development of hydrogen energy is mainly due to its lubricating effect on the transition process of energy structure. Hydrogen energy can effectively absorb the waste electricity generated by renewable energy sources such as wind power, hydropower, and photovoltaic power generation through water electrolysis. This allows the electricity that cannot be connected to the grid to be stored through hydrogen storage and flexibly utilized downstream in the hydrogen energy industry chain.

[0003] Currently, hydrogen is primarily used in the industrial sector as a chemical raw material and gas fuel. Using hydrogen as a fuel through equipment such as fuel cells and burners is a key driver of carbon emission reduction in my country's thermal power industry. However, due to economic constraints, supporting infrastructure development, and related technical bottlenecks, the use of pure hydrogen as a fuel, with the exception of initial commercialization in the mobile transportation sector through proton exchange membrane fuel cells, remains a long way off for deployment in other sectors. Its overall contribution to the decarbonization of the energy structure is very limited. Blending hydrogen into natural gas to form a hydrogen-blended natural gas mixture and then burning it is currently one of the best transitional solutions for hydrogen energy to promote the decarbonization of the energy structure. Existing burners use methods such as spraying to ensure uniform heat exchange and improve heat exchange efficiency, but these structures increase costs and are primarily limited by the inability to adjust specific temperature ranges according to actual needs, resulting in a limited range of applications. Some burners that integrate sophisticated detection instruments such as sensors are expensive, making them inaccessible to widespread use. Furthermore, burners that fail to exchange heat with the liquid can easily cause burns to the user.

[0004] Because hydrogen's physical and chemical properties differ significantly from those of natural gas, as do its combustion parameters such as flammability range, combustion temperature, and combustion velocity, using a natural gas burner to directly burn hydrogen can easily lead to combustion instabilities such as thermoacoustic instability and flashback. Furthermore, because hydrogen and natural gas cannot fully mix, combustion efficiency is low and incomplete. Excessive hydrogen in certain areas can also lead to deflagration. Furthermore, because hydrogen has a very low density, its flow distribution can be uneven, easily resulting in either excess or insufficient hydrogen in certain areas of the mixed fuel.

[0005] Therefore, based on the above problems, a new combustion system is needed, which can improve the combustion efficiency by fully mixing hydrogen and natural gas, reduce carbon monoxide emissions, and avoid danger. Summary of the Invention

[0006] In view of the above problems, the present invention provides a combustion system of a hydrogen and natural gas mixed fuel, thereby improving combustion efficiency.

[0007] To achieve the above objectives, the present invention adopts the following technical solutions:

[0008] A hydrogen-blended combustion system provided with a hydrogen distribution component comprises a natural gas tank, a hydrogen production device, a hydrogen tank and a burner. The hydrogen produced by the hydrogen production device is transported to the hydrogen tank, the natural gas tank is connected to the burner through a main pipeline, and the hydrogen tank is connected to the main pipeline through a hydrogen pipeline. Natural gas and hydrogen are mixed in the main pipeline to form a mixed fuel, which is then transported to the burner through the main pipeline. The hydrogen pipeline is vertically connected to the main pipeline, and the connection position of the hydrogen pipeline and the main pipeline is arranged between the natural gas tank and the burner. It is characterized in that the hydrogen pipeline is arranged horizontally, and a hydrogen distribution component is arranged in the hydrogen pipeline. The hydrogen distribution component is a hydrogen flow equalizing device, and the hydrogen distribution component is a blade structure. The blade structure includes a plurality of blades. The flow channel between adjacent blades is horizontal, and the flow area of ​​the flow channel between adjacent blades continuously decreases along the vertical direction from bottom to top.

[0009] As an improvement, the flow area of ​​the flow channel between adjacent blades decreases continuously from bottom to top in a larger and larger range.

[0010] As an improvement, the hydrogen flow equalizing device is arranged on the hydrogen pipeline close to the main pipeline.

[0011] As an improvement, the hydrogen flow equalizing device is arranged 1-2 mm away from the connection position between the hydrogen pipeline and the main pipeline.

[0012] As an improvement, a main pipe distribution device is provided in the main pipe. The main pipe distribution device is a blade structure and is provided upstream of the connection position. The blade structure is provided with multiple blades, and the extension direction of the flow channel between adjacent blades is provided parallel to the central axis direction of the hydrogen pipeline.

[0013] As an improvement, the horizontal direction of the flow channel of the main distribution device and the horizontal direction of the flow channel of the hydrogen flow equalization device are staggered.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] 1) Based on the existing burners, a burner system with sufficient mixing is creatively proposed. By setting blades on the hydrogen pipeline and changing the gap between the blades on the hydrogen pipeline along the height direction, the local ratio of natural gas and hydrogen can be avoided, the combustion efficiency can be improved, and accidents can be avoided.

[0016] 2) Building on existing burners, a hybrid burner system with flow regulation, rectification, and equalization functions has been creatively proposed. This system, comprising upstream and downstream main pipe distribution devices and a flow-equalizing and mixing device, achieves dual control and equalization, addressing the problem of uneven inlet flow velocity at its source. The resulting flow-equalizing effect significantly improves the accuracy and stability of inlet flow and temperature measurements, thereby enhancing the economy and stability of the combustion system. Furthermore, the device's simple structure avoids the excessive pressure drop and increased operating costs associated with the additional installation of a flow-equalizing and mixing device in existing technologies, resulting in high economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the system structure of the present invention;

[0018] Figure 2 Schematic diagram of the burner mixing structure of the present invention;

[0019] Figure 3 A schematic diagram of a partial three-dimensional structure of a hybrid structure provided by the present invention is shown;

[0020] Figure 4 A second schematic diagram of a partial three-dimensional structure of the hybrid structure provided by the present invention is shown;

[0021] Figure 5 A third schematic diagram of a partial three-dimensional structure of the hybrid structure provided by the present invention is shown;

[0022] Figure 6 The split blade structure of the present invention is shown. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be supplemented below with reference to the accompanying drawings in the embodiments of the present invention.

[0024] Figure 1-4 The schematic diagram of the structure of the hybrid burner of the present invention is shown. Figure 1 As shown, a combustion system for a hydrogen and gas mixed fuel includes a natural gas tank, a hydrogen production device, a hydrogen tank and a burner 3. The hydrogen produced by the hydrogen production device is transported to the hydrogen tank. The natural gas tank is connected to the burner 3 through a main pipeline 1. The hydrogen tank is connected to the main pipeline through a hydrogen pipeline 2. Natural gas and hydrogen are mixed in the main pipeline 1 to form a mixed fuel, which is then transported to the burner 3 through the main pipeline.

[0025] like Figure 2 As shown, the hydrogen pipeline 2 is arranged vertically with the main pipeline 1, and the hydrogen pipeline 2 is arranged between the natural gas tank and the burner 3. The main pipe distribution device 4 is arranged in the main pipeline 1, and the main pipe distribution device 4 is arranged upstream of the connection position between the hydrogen pipeline and the main pipeline; Figure 3 As shown, the main pipe distribution device 4 is a blade structure, and the blade structure is provided with a plurality of blades.

[0026] As an improvement, the hydrogen pipeline is arranged horizontally, and a hydrogen distribution component is arranged in the hydrogen pipeline. The hydrogen distribution component is a hydrogen flow equalization device 6. The hydrogen distribution component is a blade structure. The blade structure includes multiple blades. The flow channel between adjacent blades is horizontal. From bottom to top along the vertical direction, the flow area of ​​the flow channel between adjacent blades continuously decreases.

[0027] Because hydrogen density is too low, it tends to gather at the top during its flow. By adjusting the flow area, hydrogen can be distributed more or less evenly across the entire pipe cross section, avoiding localized excess or deficiency, thereby increasing the overall ratio of hydrogen to natural gas.

[0028] As an improvement, the main pipeline is set horizontally.

[0029] As an improvement, the flow area of ​​the flow passages between adjacent blades is continuously reduced in an increasingly larger range from bottom to top. Through the above arrangement, the hydrogen distribution can be further ensured to be balanced, and the combustion efficiency can be further improved.

[0030] As an improvement, the hydrogen flow equalization device 6 is placed near the main pipeline in the hydrogen pipeline, preferably 1-2 mm away from the connection point between the hydrogen pipeline and the main pipeline. This ensures that the hydrogen is evenly distributed in accordance with the initial distribution state and can cooperate with the main distribution device 4 near the connection point to achieve a more even mixing ratio.

[0031] As an improvement, a main pipe distributor 4 is installed in the main pipe. This main pipe distributor is a vane-shaped structure located upstream of the connection point. The vane structure has multiple vanes, and the flow paths between adjacent vanes extend horizontally. The gaps between the main pipe distributor and the hydrogen pipe distributor are horizontal and parallel to each other, which can reduce impact and noise when the fluids are mixed.

[0032] As an improvement, the flow channels of the main distribution device and the hydrogen equalization device are horizontally staggered. By staggering the two flow channels, during mixing, the hydrogen layer flowing out of the hydrogen flow channel enters the space between the two layers of natural gas in the adjacent, staggered natural gas flow channel layers. Simultaneously, the natural gas flowing out of the natural gas flow channel layer enters the space between the adjacent hydrogen layers. This staggers and separates the natural gas and hydrogen layers, resulting in more even distribution, reduced noise, and less impact.

[0033] As an improvement, different from the previous embodiments, the flow passages between adjacent blades on the main pipe are arranged in a vertical direction. Figure 4 shown.

[0034] The main pipeline is provided with a fuel flow balancing device 5, which is located downstream of the connection position between the hydrogen pipeline and the main pipeline; a hydrogen flow balancing device 6 is provided on the hydrogen pipeline 2, and the hydrogen pipeline 2 is provided on the pipeline between the inlet main pipe distribution device 4 and the flow balancing device 5, and the main pipe distribution device 4 and the flow balancing device 5 are multi-blade structures.

[0035] When the extension direction of the flow channel between adjacent blades on the main pipeline is set perpendicular to the central axis direction of the hydrogen pipeline (that is, set in the vertical direction), the inclination angles of the swing directions of adjacent blades of the main distribution device 4 are different. As the distance from the hydrogen pipeline increases, the angle between the swing direction of the blade and the central axis direction of the hydrogen pipeline becomes smaller and smaller. The angle is the angle between the central axis of the hydrogen pipeline in the direction of hydrogen flow and the inclination direction of the blade.

[0036] Near the hydrogen outlet, the hydrogen flow rate is the highest, and the mixing of hydrogen and natural gas is optimal. This results in uneven mixing overall. As the distance from the outlet increases, the hydrogen flow rate decreases, and the mixing becomes worse, resulting in poor overall mixing. The present invention improves the blade angle so that the natural gas flow rate decreases along the direction in which the hydrogen enters the natural gas pipeline, resulting in balanced mixing across the entire area and improved overall mixing uniformity.

[0037] Based on the existing burner, the present invention creatively proposes an inlet flow regulation system with flow regulation function and also has the functions of equalizing proportion, rectifying and equalizing flow. It includes two upstream and downstream split regulating devices to realize dual control and dual equalizing flow, which has a significant equalizing effect on the proportion of natural gas and hydrogen and has high economic benefits.

[0038] Preferably, as the distance from the hydrogen pipeline increases, the angle between the blade and the liquid flow direction in the direction of the central axis of the hydrogen pipeline becomes smaller and smaller, and the amplitude thereof increases continuously. By changing the amplitude of the angle, the effect of balancing the proportions can be better improved, and overall uniform mixing can be achieved.

[0039] Although the above method can ensure that natural gas and hydrogen are mixed in a sufficient proportion and avoid excessive natural gas or hydrogen in some areas, which may cause hydrogen explosion, it will lead to uneven distribution of fuel in the main pipeline, resulting in more fuel near the hydrogen pipeline and less fuel far away from the hydrogen pipeline. In order to ensure uniform fuel distribution in the entire pipeline, the following improvements have been made:

[0040] As an improvement, the spacing between adjacent blades of the main distribution device 4 varies, decreasing with distance from the secondary pipeline. Near the hydrogen outlet, the hydrogen flow rate is highest, and mixing of hydrogen and natural gas is optimal. This results in uneven mixing overall. As the distance from the outlet increases, hydrogen flow decreases, and mixing worsens, resulting in poor overall mixing. By adjusting the gap size, the present invention reduces the natural gas flow rate along the direction in which hydrogen enters the natural gas pipeline, resulting in more balanced mixing across the entire area and a more uniform natural gas-hydrogen ratio overall.

[0041] As the distance from the secondary pipeline increases, the gap between adjacent blades becomes smaller and smaller. The above setting can further ensure the mixing balance of the entire area and improve the overall uniformity of the mixed natural gas and hydrogen ratio.

[0042] Preferably, Figure 3 As shown, a flow equalizer 5 is installed downstream of the main pipeline connecting the main pipeline to the hydrogen pipeline. This flow equalizer and mixer is a vane structure with multiple blades. As an improvement, the distance between the fuel flow channels between adjacent blades increases as the distance from the hydrogen pipeline increases. This arrangement allows the fuel to flow as far away from the hydrogen pipeline as possible, thereby improving the previously mixed fuel concentration near the hydrogen pipeline and ensuring that the fuel is evenly distributed throughout the main pipeline.

[0043] As an improvement, the distance between the fuel flow channels of adjacent blades further from the hydrogen pipeline increases. The above arrangement can further distribute the fuel evenly throughout the entire pipeline.

[0044] When the flow-equalizing and mixing devices are partially open, each set of two opposing blades can divert the flow in two directions. Main flow distributor 4 diffuses the flow horizontally, while flow equalizer 5 diffuses it vertically. When main flow distributors 4 and 5 are combined, the two sets of regulating devices are perpendicular to each other, allowing for even greater flow uniformity in all four directions.

[0045] Preferably, the blades can adjust their angles and the spacing between adjacent blades to control the flow of the fluid.

[0046] Based on the existing burner, the present invention creatively proposes an inlet flow regulation system that has the functions of flow regulation and also has the functions of equalizing proportions, rectifying and equalizing flow. It includes two upstream and downstream devices to achieve dual control and dual equalization, which significantly improves the equalization effect of natural gas and hydrogen, and subsequently, the equalization device is used to evenly distribute the gas throughout the pipeline. The combination of the above two devices can achieve flow control, uniform proportional distribution, and uniform fuel distribution throughout the pipeline. Preferably, the mixing device 6 provided downstream of the equalization device 5 is a blade structure, which includes a plurality of blades, and adjacent blades are split adjustment structures.

[0047] As an improvement, the extension direction of the flow channel between adjacent blades of the flow balancing device 5 is arranged parallel to the central axis direction of the hydrogen pipeline.

[0048] Preferably, multiple mixing devices 6 can be provided, with the mixing mechanism blades comprising a horizontal structure arranged horizontally with the blade gap and a vertical structure arranged vertically, with the horizontal and vertical structures arranged alternately. After the mixing devices in different directions are combined, since the two sets of regulating devices are perpendicular to each other, the flow can be diffused in all four directions, horizontally and vertically, achieving a higher degree of homogenization.

[0049] Preferably, the adjacent blades of the device 4-6 are split adjustment structures, such as Figure 6 shown.

[0050] The flow of natural gas needs to be controlled. The split-type regulating device of the present invention has both flow balancing and flow regulating functions.

[0051] Preferably, the flow equalizing device 6 is a multi-blade structure, wherein adjacent blades are in a split adjustment structure. By providing the split adjustment structure, the input hydrogen can be made uniform.

[0052] Preferably, the main pipe distribution device 4, hydrogen flow equalization device 6, and fuel flow equalization device 5 are independently adjustable. Different device openings result in different flow resistances and varying flow equalization and mixing effects. When the equipment can withstand greater flow resistance, a smaller device opening can be used to achieve better flow equalization and mixing effects.

[0053] As an improvement, the main pipe distributor 4 is positioned near the connection point between the hydrogen pipeline and the main pipe, preferably 1-2 mm from the most upstream point of the connection point. By placing both the main pipe distributor 4 and the hydrogen flow equalizer 6 close to the connection point, the natural gas and hydrogen can be more accurately distributed according to the initial distribution of the blades. This allows the gas distributed by the main pipe distributor 4 to be more accurately distributed with distance from the hydrogen pipeline, thereby achieving more accurate overall proportional distribution.

[0054] When the blade angle (e.g. Figure 4When angle B) is small (approaching a closed state), flow resistance is high; conversely, when the blade angle is large (approaching an open state), flow resistance is low. If the flow velocity is high in a certain area, the nearby blades should be adjusted to a smaller angle (approaching a closed state), which can induce fuel to flow toward the area with the larger blade angle, thus achieving a flow equalization effect. If the flow velocity is low in a certain area, the nearby blades should be adjusted to a smaller angle (approaching a closed state), which can induce fuel to flow toward the area with the larger blade angle, thus achieving a flow equalization effect. If all blades have the same angle, flow equalization can still be achieved, but the effect will be less effective. By adjusting the angles as described above, the optimal flow equalization effect can be achieved with minimal resistance.

[0055] As an improvement, the vertical orientation of the flow passages between adjacent blades on the main pipe is designed so that the angle between adjacent opposing blades of the main pipe distributor 4 decreases as the distance from the hydrogen pipe to the main pipe connection (where the hydrogen pipe enters the main pipe) increases. By modifying the opposing blade angles, the present invention reduces the natural gas flow rate along the direction where hydrogen enters the gas flow passage, aligning it with the hydrogen flow rate. This ensures a substantially consistent local ratio of natural gas to hydrogen, improving the overall mixing effect.

[0056] Preferably, as the distance from the connection point between the hydrogen pipeline and the main pipeline gets closer, the angle between the blades of the main pipe distribution device 4 becomes smaller and smaller, and the amplitude thereof increases continuously. By changing the amplitude of the angle, the uniform mixing effect can be better improved.

[0057] When the flow paths between adjacent blades on the main pipe extend perpendicular to the central axis of the hydrogen pipe, as an improvement, the distribution density of the blades in the main pipe distribution device 4 decreases as the distance from the hydrogen pipe increases. The hydrogen flow rate decreases with increasing distance from the inlet. By improving the blade distribution density, the present invention adjusts the blade distribution density along the direction of the hydrogen inlet channel to match the hydrogen flow rate, ensuring a substantially consistent local ratio of natural gas to hydrogen, thereby improving the overall mixing effect.

[0058] Preferably, as the distance from the connection point of the hydrogen pipeline to the main pipeline gets closer, the distribution density of the blades of the main distribution device 4 decreases and increases. By changing the distribution density, the heat exchange effect can be better improved and the overall heat exchange can be more uniform.

[0059] Preferably, multiple mixing devices 6 are provided, and the angles between adjacent blades in the mixing device become smaller and smaller along the flow direction of the fuel in the main pipeline. By varying the amplitude, on the one hand, the flow distribution can be further uniformed while maintaining low flow resistance.

[0060] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made based on the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A hydrogen blending and combustion system with a hydrogen distribution component, comprising a natural gas tank, a hydrogen production device, a hydrogen tank, and a burner. The hydrogen produced by the hydrogen production device is transported to the hydrogen tank, the natural gas tank is connected to the burner via a main pipeline, and the hydrogen tank is connected to the main pipeline via a hydrogen pipeline. Natural gas and hydrogen are mixed in the main pipeline to form a mixed fuel, which is then transported to the burner via the main pipeline. The hydrogen pipeline is vertically connected to the main pipeline, and the connection position of the hydrogen pipeline and the main pipeline is set between the natural gas tank and the burner. The system is characterized in that: The hydrogen pipeline is arranged horizontally, and a hydrogen distribution component is arranged in the hydrogen pipeline. The hydrogen distribution component is a hydrogen flow equalization device. The hydrogen distribution component is a blade structure. The blade structure includes multiple blades. The flow channel between adjacent blades is horizontal. Along the vertical direction from bottom to top, the flow area of ​​the flow channel between adjacent blades continuously decreases.

2. The combustion system according to claim 1, wherein: Along the vertical direction from bottom to top, the flow area of ​​the flow channel between adjacent blades continues to decrease at an increasingly larger rate.

3. The combustion system according to claim 1, wherein: The hydrogen flow equalizing device is arranged on the hydrogen pipeline close to the main pipeline.

4. The combustion system according to claim 3, wherein: The hydrogen flow equalizing device is set at a distance of 1-2 mm from the connection position between the hydrogen pipeline and the main pipeline.

5. The combustion system according to claim 1, wherein: A main pipe distribution device is provided in the main pipe. The main pipe distribution device is a blade structure and is provided upstream of the connection position. The blade structure is provided with multiple blades, and the extension direction of the flow channel between adjacent blades is provided parallel to the central axis direction of the hydrogen pipe.

6. The combustion system according to claim 5, wherein: The horizontal direction of the flow channel of the main distribution device and the horizontal direction of the flow channel of the hydrogen flow equalization device are staggered with each other.

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