Method and device for measuring hydrogen-doped mixing uniformity of natural gas

Abstract

The invention discloses a natural gas hydrogen-doped mixing uniformity measuring method and device, and relates to the technical field of fuel gas conveying, and the method comprises the following steps: collecting mass flow data of a section position of a measured pipeline; calculating the collected mass flow rates at different measurement positions to obtain the concentration distribution of the gas; and the mixing uniformity is calculated according to the dispersion degree of gas concentration distribution of the section of the detected position. The measuring device comprises a hydrogen injection pipe section, a hydrogen and natural gas mixing section and a natural gas hydrogen-doped mixing uniformity measuring section. According to the method and the device for measuring the mixing uniformity of the hydrogen-doped natural gas, the problem that the mixing uniformity of the hydrogen-doped natural gas conveying pipe is difficult to detect at present is solved, the mixing uniformity of the natural gas and the hydrogen can be detected by the method and the device, and the detection and monitoring of the concentration distribution of the natural gas and the hydrogen in the hydrogen-doped natural gas conveying pipe are solved; the detection result is reliable, the safety is high, and a guarantee is provided for the transportation safety of a hydrogen-doped natural gas pipeline and the stability and safety of fuel gas use.

Description

Technical Field

[0001] This invention relates to the field of gas transmission technology, specifically to a method and apparatus for determining the uniformity of hydrogen blending in natural gas. Background Technology

[0002] Hydrogen energy, as a clean and low-carbon energy source, is widely used and is gradually becoming an important direction for global energy technology revolution and industrial transformation. Due to numerous technical challenges in the large-scale utilization of pure hydrogen, it is currently in the stage of blending hydrogen with natural gas for combustion. The application of clean energy through natural gas blending with hydrogen is an effective solution for the transition from fossil fuels to pure hydrogen energy. Because of the significant differences in properties between natural gas and hydrogen, the mixing uniformity of the two gases is low in hydrogen-blended natural gas pipelines, easily leading to stratification, which directly affects the combustion stability and safety of the mixture. Therefore, there is an urgent need to detect the mixing uniformity of natural gas and hydrogen.

[0003] Patent (CN 113739156 A) discloses a natural gas hydrogen blending device and method. The device includes a mixing tank and a natural gas jet system, a swirl plate, a hydrogen jet swirl system, and a flow equalization plate arranged sequentially from top to bottom within the mixing tank. The swirl plate rotates in the opposite direction to the hydrogen jet swirl system, which sprays downwards. A mixed gas outlet is located at the top of the mixing tank. This mixing device can create opposing, counteracting natural gas and hydrogen swirls, ensuring thorough mixing of the natural gas and hydrogen. This promotes stable combustion of the entire mixture and reduces or even eliminates the generation of pollutants such as nitrogen oxides and other harmful gases.

[0004] Patent (CN 117195428 A) discloses a method and system for optimizing the structure of a hydrogen-blended natural gas mixer based on numerical simulation. The method is based on a parametric geometric model, establishes a CFD model of the hydrogen-blended natural gas mixer, and performs numerical simulation of the CFD model of the hydrogen-blended natural gas mixer with the goal of achieving the best mixing uniformity at the outlet section of the flow channel.

[0005] Patent (CN 117707038 A) discloses a natural gas and hydrogen blending system and method. The system includes: a multi-stage blender, a single-point blending system, a first detector, and a PLC controller. The first detector is located at the outlet of the multi-stage blender and connected to the PLC controller. It includes multiple concentration sensors, which are used to monitor the concentration values ​​at three points (upper, middle, and lower) of the outlet flow channel cross-section. The multi-stage blender is used to blend hydrogen and natural gas that meet the hydrogen blending concentration requirements to obtain a mixed gas. The PLC controller is used to control the opening or closing of different single-point blenders in the single-point blending system according to the comparison results of the concentration values ​​at the upper, middle, and lower points with the target value, so as to further blend the mixed gas.

[0006] Currently, the focus of research on the uniformity of hydrogen-blended natural gas is on the design of blending devices and vertical simulation of blending uniformity, but the detection of the uniformity of natural gas and hydrogen blending in the pipeline is still lacking. Summary of the Invention

[0007] Based on the problem pointed out in the background art that there is currently a lack of detection of the mixing uniformity of natural gas and hydrogen in hydrogen-blended natural gas pipelines, the purpose of this invention is to provide a method and apparatus for measuring the mixing uniformity of hydrogen-blended natural gas, aiming to solve the current problem of detecting the mixing uniformity of hydrogen and natural gas at different locations in hydrogen-blended natural gas, and to provide a reference for the research on the stability and safety of hydrogen-blended natural gas pipeline transportation and combustion.

[0008] This invention is achieved through the following technical solution:

[0009] In a first aspect, this application provides a method for determining the uniformity of hydrogen-blended natural gas, comprising the following steps:

[0010] Collect mass flow data at the cross-sectional location of the pipe being measured;

[0011] The concentration distribution of the gas was obtained by calculating the mass flow rate collected at different measurement locations.

[0012] The mixing uniformity is calculated by the degree of dispersion of the gas concentration distribution at the detected cross-section.

[0013] This measurement method solves the problem of detecting and monitoring the concentration distribution of natural gas and hydrogen in hydrogen-blended natural gas pipelines. The test results are reliable and safe, providing a guarantee for the safe transportation of hydrogen-blended natural gas pipelines and the stability and safety of gas use.

[0014] Furthermore, the formula for calculating the blending uniformity is:

[0015]

[0016] in, c i =m i / m;

[0017] In the above formula, c represents the average gas concentration at different measurement locations. i Gas concentration value at each measurement point; n is the number of measurement points; σ is the mixing uniformity; m is the mass flow rate of the mixed gas in the hydrogen-blended natural gas pipe; m i The mass flow rate measured at each monitoring point.

[0018] Secondly, a device for measuring the uniformity of hydrogen-blended natural gas includes a hydrogen injection pipe section, a hydrogen-natural gas mixing section, and a hydrogen-blended natural gas mixing uniformity measurement section.

[0019] Furthermore, the hydrogen injection pipeline section includes a natural gas transmission pipeline, and a hydrogen injection pipe is installed at a certain distance from the inlet end of the natural gas transmission pipeline for injecting hydrogen into the natural gas transmission pipeline.

[0020] The distance between the hydrogen injection pipe and the inlet of the natural gas pipeline can be determined by those skilled in the art based on the actual situation, so as to ensure that the hydrogen enters the natural gas pipeline and mixes more evenly with the natural gas.

[0021] Furthermore, the outlet end of the gas injection pipe is provided with multiple gas outlet holes.

[0022] Multiple vent holes can be opened at the outlet end of the hydrogen injection pipe to achieve the desired mixing of natural gas and hydrogen.

[0023] Furthermore, a static mixer is installed inside the pipeline of the hydrogen and natural gas mixing section.

[0024] Installing a static mixer inside the pipeline in the hydrogen-natural gas mixing section allows for the blending of hydrogen and natural gas.

[0025] Furthermore, the pipeline of the hydrogen and natural gas mixing section is connected to the pipeline of the natural gas hydrogen blending uniformity measurement section via a flange.

[0026] Furthermore, the natural gas hydrogen blending uniformity measurement section is equipped with a flow divider grid and a mass flow meter. The installation method of the flow divider grid corresponds to the installation method of the mass flow meter, which is used to prevent mutual interference between the measured fluids.

[0027] Furthermore, multiple mass flow meters are installed.

[0028] Multiple mass flow meters are installed at a specific cross-section in the transport pipe at the rear end of the static mixer to measure the mass flow rate of hydrogen at different locations on the pipe cross-section. The more mass flow meters there are, the higher the final mixing uniformity will be. A flow divider grid is installed in front of the mass flow meter installation location to prevent the fluids from interfering with each other.

[0029] Furthermore, a mass flow meter is installed at the rear end of the natural gas hydrogen blending uniformity measurement section to measure the mass flow rate of the mixed gas in the transport pipeline.

[0030] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0031] (1) The method and apparatus for measuring the uniformity of hydrogen-blended natural gas in this invention solves the problem that the uniformity of blending in hydrogen-blended natural gas pipelines is difficult to detect. The method and apparatus can detect the uniformity of the blending of natural gas and hydrogen, and solve the problem of detecting and monitoring the concentration distribution of natural gas and hydrogen in hydrogen-blended natural gas pipelines. The detection results are accurate and reliable, and the safety is high, which provides a guarantee for the safe transportation of hydrogen-blended natural gas pipelines and the stability and safety of gas use.

[0032] (2) The method for determining the uniformity of hydrogen-blended natural gas in this invention is simple, low-cost, universal, and easy to scale up. Attached Figure Description

[0033] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0034] Figure 1 This is a perspective view of a natural gas hydrogen-blending uniformity measuring device according to the present invention;

[0035] Figure 2 for Figure 1 Enlarged view of A in the middle;

[0036] Figure 3 This is a schematic diagram of the static mixer in this invention;

[0037] Figure 4 This is a schematic diagram of the internal structure of a natural gas hydrogen-blended mixing uniformity measuring device according to the present invention.

[0038] The attached diagram shows the markings and corresponding component names:

[0039] 01-Natural gas transmission pipeline, 02-Hydrogen injection pipe, 03-Static mixer, 04-Diverter grid, 05-Mass flow meter, 06-Flange, 07-Hydrogen injection pipe section, 08-Hydrogen and natural gas mixing section, 09-Natural gas with hydrogen blending uniformity measurement section. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0041] The embodiments of this application are disclosed in detail below with appropriate reference to the accompanying drawings. However, unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of practically identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0042] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0043] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0044] The terms “comprising,” “including,” or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0045] Example 1

[0046] like Figures 1-4 As shown, this embodiment provides a natural gas hydrogen blending uniformity measuring device, wherein the device structure includes a hydrogen injection pipe section 07, a hydrogen and natural gas mixing section 08, and a natural gas hydrogen blending uniformity measuring section 09.

[0047] Specifically, the hydrogen injection pipe 02 section includes a natural gas transmission pipeline 01. The hydrogen injection pipe 02 is installed at a certain distance from the inlet of the natural gas transmission pipeline 01 to inject hydrogen into the natural gas transmission pipeline 01. To achieve the desired blending of natural gas and hydrogen, multiple gas outlet holes are provided at the outlet end of the hydrogen injection pipe 02.

[0048] Specifically, the pipeline of hydrogen and natural gas mixing section 08 is connected to the pipeline of natural gas hydrogen blending uniformity measurement section 09 via flange 06.

[0049] Specifically, the natural gas hydrogen blending uniformity measurement section 09 is equipped with a flow divider grid 04 and a mass flow meter 05. The installation method of the flow divider grid 04 corresponds to the installation method of the mass flow meter 05, which is used to prevent mutual interference between the measured fluids.

[0050] Multiple mass flow meters 05 are installed at this location. These multiple mass flow meters 05 are installed at a specific cross-section in the transport pipe at the rear end of the static mixer 03, where the mass flow rate of hydrogen at different locations in the pipe cross-section needs to be measured. The more mass flow meters 05 there are, the higher the final measured mixing uniformity will be. A flow divider grid 04 is installed in front of the installation location of the mass flow meters 05 to prevent the fluids from affecting each other.

[0051] Specifically, a mass flow meter 05 is installed at the rear end of the natural gas hydrogen blending uniformity measurement section 09 to measure the mass flow rate of the mixed gas in the transport pipeline.

[0052] When using this device to determine the uniformity of hydrogen blending in natural gas, a certain concentration of hydrogen is injected into the natural gas transmission pipeline 01 through the hydrogen injection pipe 02. The hydrogen is then discharged into the natural gas transmission pipeline 01 through the outlet of the hydrogen injection pipe 02, causing the hydrogen entering the natural gas transmission pipeline 01 to mix with the natural gas in the natural gas transmission pipeline 01 and flow together. The mixed gas flows through the diversion grid 04 and then enters the mass flow meter 05, which can measure the gas flow at different measurement positions on the pipeline cross-section. At the rear end of the hydrogen-blended natural gas pipeline, after the mixed gas flows through the mass flow meter 05, the mass flow rate of the mixed gas can be measured, and then the uniformity of hydrogen blending in natural gas can be calculated based on the measured value.

[0053] This device for measuring the uniformity of hydrogen blending in natural gas solves the problem of difficulty in detecting the uniformity of blending in hydrogen-blended natural gas pipelines. The method and device can detect the uniformity of the blending of natural gas and hydrogen, solving the problem of detecting and monitoring the concentration distribution of natural gas and hydrogen in hydrogen-blended natural gas pipelines. The detection results are accurate, reliable, and highly safe, providing a guarantee for the safe transportation of hydrogen-blended natural gas pipelines and the stability and safety of gas use.

[0054] Example 2

[0055] This embodiment provides a method for determining the uniformity of hydrogen-blended natural gas, using the hydrogen-blended natural gas mixing uniformity measuring device from Embodiment 1. The specific measurement method is as follows:

[0056] S1. Collect mass flow data at the cross-sectional location of the pipe being measured;

[0057] S2. Calculate the gas concentration distribution by collecting mass flow rates at different measurement locations;

[0058] S3. The mixing uniformity is calculated by the dispersion of the gas concentration distribution at the cross-section of the tested location.

[0059] The calculation formula is as follows:

[0060]

[0061] In the above formula, c represents the average gas concentration at different measurement locations. i The gas concentration value at each measurement location; n is the number of measurement locations; σ is the mixing uniformity. The larger the uniformity value, the more uniformly the natural gas and hydrogen are mixed at the measurement location.

[0062]

[0063] c i =m i / m;

[0064] In the above formula, m is the mass flow rate of the mixed gas in the hydrogen-blended natural gas pipeline; m i The mass flow rate measured at each monitoring point.

[0065] When using this measurement method and apparatus for actual testing, a certain concentration of hydrogen gas is injected into the natural gas pipeline through the hydrogen injection pipe. After passing through the outlet of the hydrogen injection pipe, the natural gas and hydrogen gas have a good mixing effect. After flowing through the static mixer, the natural gas and hydrogen gas are mixed together, and the mixed gas flows together in the transport pipeline. After passing through the diversion grid, the mixed gas enters the mass flow meter, which can measure the gas mass flow rate (m) at different measurement locations on the pipeline cross-section. i At the rear end of the hydrogen-blended natural gas pipeline, after the mixed gas flows through the mass flow meter, the mass flow rate m of the mixed gas can be measured.

[0066] The mass flow rate measured at different locations on the pipe cross-section is m. i And the mass flow rate m of the mixed gas in the hydrogen-blended natural gas pipeline, substituting into formula c i =m i / m, the gas concentration at each measurement location can be obtained; substitute the calculated gas concentrations at different locations into the formula. The average concentration can be obtained.

[0067] Substitute the calculated concentration and average concentration at the measurement location into the formula. This allows us to obtain the uniformity of hydrogen and natural gas mixing at the cross-section of the measuring pipe.

[0068] The aforementioned measurement method can be programmed into a computer, which can be stored in a memory and installed on a computer device.

[0069] Computer devices can be desktop computers, laptops, handheld computers, cloud servers, and other computing devices that allow human-computer interaction with users through keyboards, mice, remote controls, touchpads, or voice control devices.

[0070] The storage device includes at least one type of readable storage medium, including flash memory, hard disk, multimedia card, card-type memory (e.g., SD or D-interface display memory), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, disk, optical disk, etc. In some embodiments, the storage device may be an internal storage unit of the computer device, such as the hard disk or RAM of the computer device. In other embodiments, the storage device may also be an external storage device of the computer device, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., provided on the computer device. Of course, the storage device may include both internal and external storage units of the computer device. In this embodiment, the storage device is often used to store the operating system and various application software installed on the computer device, such as the program code for running the sulfur deposition prediction method based on multiphase flow simulation and node analysis. In addition, the storage device may also be used to temporarily store various types of data that have been output or will be output.

[0071] Additionally, the computer device includes a processor for executing computer programs. In some embodiments, the processor may be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other data processing chip. The processor is typically used to control the overall operation of the computer device. In this embodiment, the processor is used to run program code stored in memory or process data.

[0072] Computer program instructions may also be loaded onto a computer or other scientifically programmed data processing device, causing a series of operational steps to be performed on the computer or other scientifically programmed device to produce computer-implemented processing.

[0073] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0074] Throughout this specification, references to "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. Therefore, the phrases "an embodiment," "an example," "an example," or "an example" appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0075] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention. It is obvious to those skilled in the art that this application is not limited to the details of the above exemplary embodiments, and that the present application can be implemented in other specific forms without departing from the spirit or basic characteristics of the present application. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this application is defined by the appended claims rather than the foregoing description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included within this application.

Claims

1. A method for determining the uniformity of hydrogen-blended natural gas, characterized in that, Includes the following steps: Collect mass flow data at the cross-sectional location of the pipe being measured; The concentration distribution of the gas was obtained by calculating the mass flow rate collected at different measurement locations. The mixing uniformity is calculated by the degree of dispersion of the gas concentration distribution at the detected cross-section.

2. The method for determining the uniformity of hydrogen-blended natural gas according to claim 1, characterized in that, The formula for calculating the uniformity of blending is: in, c i =m i δm; In the above formula, c represents the average gas concentration at different measurement locations. i Gas concentration value at each measurement point; n is the number of measurement points; σ is the mixing uniformity; m is the mass flow rate of the mixed gas in the hydrogen-blended natural gas pipe; m i The mass flow rate measured at each monitoring point.

3. A device for determining the uniformity of hydrogen-blended natural gas, characterized in that, It includes a hydrogen injection pipeline section (07), a hydrogen and natural gas mixing section (08), and a natural gas-hydrogen blending uniformity measurement section (09).

4. The apparatus for determining the uniformity of hydrogen-blended natural gas as described in claim 3, characterized in that, The hydrogen injection pipe section (07) includes a natural gas transmission pipeline (01), and a hydrogen injection pipe (02) is installed at a certain distance from the inlet end of the natural gas transmission pipeline (01) for injecting hydrogen into the natural gas transmission pipeline (01).

5. The apparatus for determining the uniformity of hydrogen-blended natural gas as described in claim 4, characterized in that, The outlet end of the gas injection pipe has multiple gas outlet holes.

6. The apparatus for determining the uniformity of hydrogen-blended natural gas as described in claim 3, characterized in that, A static mixer (03) is installed inside the pipeline of the hydrogen and natural gas mixing section (08).

7. The apparatus for determining the uniformity of hydrogen-blended natural gas as described in claim 3, characterized in that, The pipeline of the hydrogen and natural gas mixing section (08) is connected to the pipeline of the natural gas hydrogen blending uniformity measurement section (09) via a flange (06).

8. The apparatus for determining the uniformity of hydrogen-blended natural gas as described in claim 3, characterized in that, The natural gas hydrogen blending uniformity measurement section (09) is equipped with a flow divider grid (04) and a mass flow meter (05). The installation method of the flow divider grid (04) corresponds to the installation method of the mass flow meter (05) to prevent mutual interference between the measured fluids.

9. The apparatus for determining the uniformity of hydrogen-blended natural gas as described in claim 8, characterized in that, Multiple mass flow meters (05) are installed.

10. The apparatus for determining the uniformity of hydrogen-blended natural gas as described in claim 3, characterized in that, A mass flow meter (05) is installed at the rear end of the natural gas hydrogen blending uniformity measurement section (09) to measure the mass flow rate of the mixed gas in the transport pipeline.

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