Natural gas two-stage mixing device

Abstract

The utility model discloses a two-stage natural gas mixing device and relates to the technical field of hydrogen mixing of natural gas. An inlet structure is arranged at the lower part of the shell, and an outlet structure is arranged at the upper part of the shell; the coarse mixing structure is arranged in the inlet structure and is used for realizing first-stage mixing of natural gas and hydrogen; the coarse mixing structure comprises rotational flow blades and a central pipe, wherein the rotational flow blades are welded on the periphery of the central pipe; the fine mixing structure is arranged in the shell, is higher than the inlet structure and is used for realizing second-stage mixing of the natural gas and the hydrogen; the fine mixing structure comprises a distribution disc and distribution elements, the distribution disc is of a cone structure with an opening gradually becoming larger from bottom to top, multiple layers of steps are formed on the inner wall of the cone structure, and a plurality of distribution elements are evenly arranged on each layer of step in the circumferential direction. According to the natural gas two-stage mixing device, the high mixing efficiency and the good stability of the natural gas two-stage mixing device are beneficial for reducing the later operation cost and maintenance cost.

Description

Technical Field

[0001] The utility model relates to the technical field of natural gas hydrogen mixing, in particular to a two-stage natural gas mixing device. Background Art

[0002] As global demand for clean energy continues to grow, natural gas-hydrogen fuel, due to its superior high calorific value and significant low carbon emissions, is gradually gaining a significant position in the gas-fired power generation sector. An increasing number of gas-fired power plants are choosing this fuel blend as their energy source, hoping to ensure power generation efficiency while reducing environmental impact.

[0003] However, in current natural gas-hydrogen fuel applications, a common approach is to initially mix the natural gas and hydrogen, then transport them through a pipeline system to a dedicated heater for heating. The heated mixture is then transported through another pipeline to a gas turbine for combustion and power generation. While this solution meets the operational needs of gas-fired power plants to a certain extent, it also presents several issues that need to be addressed:

[0004] 1. Because most current systems are equipped with only a single-stage blending device, this design limitation often results in incomplete mixing of natural gas and hydrogen, making it difficult to achieve ideal mixing uniformity. This not only affects the stability and efficiency of the subsequent combustion process but can also adversely affect the operation of key equipment such as gas turbines.

[0005] 2. The independent spatial arrangement of the blending and heating devices, coupled with their connection via long-distance pipelines, not only increases the complexity and maintenance difficulty of the entire system but also significantly increases the risk of leakage. Leaks at pipeline connections not only waste energy and pollute the environment, but also pose a serious threat to production safety. Furthermore, long-distance pipeline transmission increases the pressure drop of the mixed gas, reducing the overall efficiency of the system. This layout also occupies more land resources, hindering the intensive and sustainable development of power plants. Utility Model Content

[0006] The purpose of the utility model is to provide a two-stage natural gas blending device, which can more effectively mix natural gas and hydrogen. This staged blending method helps to improve the blending efficiency and make the mixed gas more uniform.

[0007] To achieve the above objectives, the technical solution of the present application is: a two-stage natural gas blending device, comprising:

[0008] a shell, the lower portion of which is provided with an inlet structure, and the upper portion of which is provided with an outlet structure;

[0009] A coarse mixing structure is provided in the inlet structure for achieving the first stage mixing of natural gas and hydrogen; the coarse mixing structure comprises swirl blades and a central tube, wherein the swirl blades are welded to the outer periphery of the central tube and to the inner wall of the inlet structure;

[0010] The fine mixing structure is arranged in the shell and is higher than the inlet structure, and is used to achieve the second-stage mixing of natural gas and hydrogen; the fine mixing structure includes a distribution plate and distribution elements. The distribution plate is a cone structure with an opening that gradually increases from bottom to top, and the inner wall of the cone structure is formed with multiple steps, and each step is evenly arranged with a number of distribution elements along the circumferential direction.

[0011] Furthermore,

[0012] The electric heater is arranged on the top of the shell to heat the mixed gas.

[0013] Furthermore,

[0014] The guide tube is arranged on the upper part of the shell and is located between the fine mixing structure and the electric heater. The end thereof is in a trumpet shape and is used to guide the mixed gas into the electric heater.

[0015] Furthermore, the distribution element has an air inlet channel, which is connected to the side air outlet channel and the top air outlet channel.

[0016] Furthermore, the side air outlet channels are of a downwardly inclined structure and are evenly opened on the upper part of the side wall of the distribution element, and the top air outlet channels are opened on the top of the distribution element.

[0017] Furthermore, the diameter of the side air outlet channel is larger than the diameter of the top air outlet channel.

[0018] Furthermore, the distribution element has a clamping platform in the middle, the lower part of the clamping platform is threadedly connected to the distribution disk, and the clamping platform is located on the step.

[0019] Furthermore, the shell is provided with an upper manhole and a lower manhole, wherein the upper manhole is used for maintenance personnel to enter the shell to check whether the distribution element is damaged or blocked; the lower manhole is used for maintenance personnel to enter the shell to check whether the swirl blades are damaged or deformed.

[0020] Furthermore, a concave sealing plate is connected to the bottom of the shell, and the concave sealing plate is connected to the dust removal duct.

[0021] Furthermore, the inlet structure includes an inlet flange, a cone inlet and an inlet pipe connected in sequence, and the coarse mixing structure is located in the inlet structure.

[0022] By adopting the above technical solution, the present invention achieves the following technical effects: The high blending efficiency and good stability of the two-stage natural gas blending device of the present application help reduce subsequent operating and maintenance costs. In addition, due to the more uniform mixed gas, energy utilization efficiency can be improved, further reducing overall costs.

[0023] This device integrates a two-stage blending structure for coarse and fine blending, along with a heater, creating an integrated, highly efficient system. This allows a single unit to simultaneously perform both the two-stage blending and heating functions, achieving a thorough mixing of natural gas and hydrogen. Furthermore, this high level of functional integration not only reduces floor space but also effectively mitigates potential leakage risks, ensuring safe and economical operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0025] Figure 1 This is a schematic diagram of the structure of a two-stage natural gas blending device;

[0026] Figure 2 Schematic diagram of the coarse blending structure;

[0027] Figure 3 Schematic diagram of the distributed component structure;

[0028] Figure 4 Schematic diagram of the distribution plate structure;

[0029] Figure 5 Schematic diagram of the connection between the distribution element and the distribution plate.

[0030] Explanation of the serial numbers in the figure: 1. Support; 2. Shell; 3. Conical shell; 4. Shell flange; 5. Electric heater; 6. Inlet flange; 7. Conical inlet; 8. Inlet pipe; 9. Swirl blade; 10. Outlet pipe; 11. Outlet flange; 12. Upper manhole; 13. Lower manhole; 14. Dust removal pipe; 15. Distribution plate; 16. Distribution element; 161. Top air outlet channel; 162. Side air outlet channel; 163. Card table; 164. Air inlet channel; 17. Guide tube; 18. Center pipe. DETAILED DESCRIPTION

[0031] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0032] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.

[0033] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" means two or more, unless otherwise clearly and specifically defined. "Several" means one or more, unless otherwise clearly and specifically defined.

[0034] In the description of this application, it should be understood that the terms "center", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0035] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0036] See also Figure 1 This embodiment provides a two-stage natural gas blending device, comprising:

[0037] The main body structure includes a shell 2 arranged on a support 1, the top of the shell 2 has a conical shell 3, the conical shell is connected to a shell flange 4, and an upper manhole 12 and a lower manhole 13 are provided on the shell; preferably, the bottom of the shell is connected to a concave sealing plate, which is connected to a dust removal duct 14;

[0038] The inlet structure is arranged at the lower part of the shell and has an inlet flange 6, a cone inlet 7 and an inlet pipe 8 connected in sequence;

[0039] The outlet structure is provided on the cone shell and has an outlet pipe 10 and an outlet flange 11 connected in sequence;

[0040] Coarse blending structure, such as Figure 2 As shown, it is welded inside the inlet pipe to achieve the first-stage mixing of natural gas and hydrogen; the structure includes swirl blades 9 and a central tube 18, the swirl blades are welded to the outer periphery of the central tube and welded to the inner wall of the inlet pipe, and the two ends of the central tube are sealed;

[0041] The fine mixing structure is arranged in the shell and higher than the inlet pipe, and is used to achieve the second stage mixing of natural gas and hydrogen; Figures 3 to 5 As shown, the structure includes a distribution plate 15 and a distribution element 16 welded in the shell. The distribution plate is a cone structure with an opening that gradually increases from bottom to top, and the inner wall of the cone structure is formed with multiple steps. Each step is evenly arranged with a number of distribution elements along the circumferential direction. The distribution element has a clamping platform in the middle, and the lower part of the clamping platform is threadedly connected to the distribution plate, and the clamping platform is located on the step.

[0042] The electric heater 5 is connected to the housing flange 4 by bolts to heat the mixed gas;

[0043] The guide tube 17 is welded inside the conical shell and extends into the top of the shell. The end is in a trumpet shape, which is used to guide the mixed gas into the electric heater. It can also change the flow state, increase the flow rate in the electric heater area, and increase the heat transfer effect. The guide tube 17 is welded to the outlet pipe 10.

[0044] During operation, natural gas and hydrogen are first mixed in the first stage through the coarse mixing structure, which can achieve a mixing accuracy of about 85%. After passing through the coarse mixing structure, the mixed gas enters the shell and its speed decreases and passes through the distribution element 16 in the fine mixing structure at a uniform speed. A plurality of downward-inclined side outlet channels are opened on the side wall of the distribution element 16, and a top outlet channel is opened on the top. When the mixed gas passes through the bottom inlet of the distribution element 16, the mixed gas forms a gas vortex in the air inlet channel of the distribution element 16 under the action of the high flow rate of the inlet, so that the mixed gas molecules are accelerated to collide and fully mixed again, and then rotate and flow out through the side outlet channel and the top outlet channel. Since the diameter of the side gas outlet channel is larger than that of the top gas outlet channel, most of the mixed gas is preferentially swirled out through the side gas outlet channel, and a small part of the mixed gas is swirled out through the top gas outlet channel. This can not only ensure that the mixed gas is fully mixed in the distribution element 16 to improve the mixing effect, but also reduce the pressure drop loss of the mixed gas after passing through the distribution element 16. The fine mixing structure can achieve 100% mixing accuracy, and then the 100% mixed mixed gas is uniformly heated through the guide tube 17 and the electric heater 5. The high-temperature mixed gas enters the downstream device through the outlet structure, and the impurities in the mixed gas that pass through the fine mixing structure are removed through the dust removal pipe 14.

[0045] During maintenance, remove the connecting bolts between the electric heater 5 and the shell flange 4, pull out the electric heater 5, enter the shell 2 through the upper manhole 12, and check whether the distribution element 16 is damaged or blocked; enter the shell 2 through the lower manhole 13 and check whether the swirl blades 9 are damaged or deformed.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A two-stage natural gas blending device, characterized in that: include: a shell, the lower portion of which is provided with an inlet structure, and the upper portion of which is provided with an outlet structure; A coarse mixing structure is provided in the inlet structure for achieving the first stage mixing of natural gas and hydrogen; the coarse mixing structure comprises swirl blades and a central tube, wherein the swirl blades are welded to the outer periphery of the central tube and to the inner wall of the inlet structure; The fine mixing structure is arranged in the shell and is higher than the inlet structure, and is used to achieve the second-stage mixing of natural gas and hydrogen; the fine mixing structure includes a distribution plate and distribution elements. The distribution plate is a cone structure with an opening that gradually increases from bottom to top, and the inner wall of the cone structure is formed with multiple steps, and each step is evenly arranged with a number of distribution elements along the circumferential direction.

2. A two-stage natural gas blending device according to claim 1, characterized in that: Also includes, The electric heater is arranged on the top of the shell to heat the mixed gas.

3. A two-stage natural gas blending device according to claim 2, characterized in that: Also includes, The guide tube is arranged on the upper part of the shell and is located between the fine mixing structure and the electric heater. The end thereof is in a trumpet shape and is used to guide the mixed gas into the electric heater.

4. A two-stage natural gas blending device according to claim 1, characterized in that: The distribution element has an air inlet channel, which is connected with the side air outlet channel and the top air outlet channel.

5. A two-stage natural gas blending device according to claim 4, characterized in that: The side air outlet channels are of a downwardly inclined structure and are evenly arranged on the upper part of the side wall of the distribution element, and the top air outlet channels are arranged on the top of the distribution element.

6. A two-stage natural gas blending device according to claim 4, characterized in that: The diameter of the side air outlet channel is greater than the diameter of the top air outlet channel.

7. The two-stage natural gas blending device according to claim 1, characterized in that: The distribution element has a clamping platform in the middle, the lower part of the clamping platform is connected with the distribution disk through threads, and the clamping platform is located on the step.

8. The two-stage natural gas blending device according to claim 1, characterized in that: The shell is provided with an upper manhole and a lower manhole, wherein the upper manhole is used for maintenance personnel to enter the shell to check whether the distribution element is damaged or blocked; the lower manhole is used for maintenance personnel to enter the shell to check whether the swirl blades are damaged or deformed.

9. The two-stage natural gas blending device according to claim 1, characterized in that: The bottom of the shell is connected with a concave sealing plate, which is communicated with the dust removal pipeline.

10. The two-stage natural gas blending device according to claim 1, characterized in that: The inlet structure comprises an inlet flange, a cone inlet and an inlet pipe which are connected in sequence, and the coarse mixing structure is located in the inlet pipe.

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