CN220633779U - Mixing arrangement of natural gas and hydrogen - Google Patents

Abstract

The utility model discloses a mixing device for natural gas and hydrogen, which relates to the technical field of gas mixing equipment, in particular to a mixing device for natural gas and hydrogen, comprising a first flange plate and a second flange plate, wherein an air outlet is formed in the first flange plate, and an air inlet is formed in the second flange plate; through the cooperation setting of the hydrogen main pipe, the expansion joint corrugated pipe and the sleeve pipe assembly, the mixing device for the natural gas and the hydrogen has the effects of improving the mixing of the natural gas and the hydrogen, buffering the pressure and reducing the shock, and the hydrogen is buffered and slowed down in the first buffer cavity and the second buffer cavity so as to realize depressurization, thereby reducing the air hammer phenomenon caused by higher pressure when the hydrogen pipeline is in air inlet, and achieving the purpose of reducing mixing shock while mixing uniformly; the corrugated pipe buffer assembly in the sleeve assembly is utilized to generate pulsating flow, and the pulsating flow strengthens the mixing effect of the converged hydrogen and the natural gas, so that the natural gas and the hydrogen are mixed more conveniently and efficiently.

Description

Mixing arrangement of natural gas and hydrogen

Technical Field

The utility model relates to the technical field of gas mixing equipment, also relates to the technical field of gas filling equipment, and particularly relates to a mixing device for natural gas and hydrogen.

Background

The research on natural gas hydrogen-adding technology is developed at home and abroad, for example, the process flows of the HCNG station mentioned in the literature such as the research on the mixing process of natural gas hydrogen-adding (08 in 2009 of gas and heat, qiao Weiyan, zhang Ning, eastern solution), the design and implementation of HCNG gas filling station (2013 of middle and outer energy, zhao Wenhao, cheng just), the production, diversion/use and European patent application EP20070763143 (publication number: EP1994266A 4) adopt the steps of pressurizing firstly, mixing secondly, storing and filling finally, and the process flow needs special gas mixing equipment to pre-mix hydrogen and natural gas, so that the equipment investment and occupied area are increased; in most cases, because the pressure levels of the hydrogen gas source and the natural gas source for mixing and generating HCNG (natural gas loading) are different, in order to ensure that the two gases are mixed in the station, the hydrogen gas and the natural gas are mixed after being regulated to the same pressure level before being mixed, and then the mixture is pressurized after being mixed, so that the energy efficiency of the whole gas station is reduced; finally, a premixing process is adopted, a storage tank for the HCNG mixed gas is often required to be arranged, and the problem of uneven density caused by gas layering possibly occurs in the process of long-term storage of the HCNG mixed gas, so that the combustion and emission characteristics of an automobile can be affected after the HCNG mixed gas is filled into an HCNG vehicle.

In published chinese patent application, publication No.: CN105090738B, patent name: a multifunctional mixed gas station for natural gas and hydrogen and a filling method thereof can realize high-precision mixed filling of hydrogen and natural gas in real time with adjustable proportion. The high-pressure multifunctional gas station system for natural gas and hydrogen comprises: the system comprises a natural gas supply system, a hydrogen gas supply system, at least one gas mixing and filling machine and a data acquisition and monitoring control (SCADA) system. The high-pressure multifunctional gas station system for natural gas and hydrogen can adjust the quantity of the natural gas supply system and the hydrogen supply system, for example, a natural gas pipe bundle gas carrier, a hydrogen pipe bundle gas carrier, a high-pressure natural gas storage bottle group and a high-pressure hydrogen storage bottle group can be increased or decreased according to the needs so as to meet different requirements of filling quantity and different scales of the gas station; the gas mixing and filling machine integrates the functions of gas mixing and filling, and can fill the gas in real time while mixing the gas, so that the mixed filling can be performed according to the filling proportion of a customer, and the possibility of gas mixing layering possibly occurring in the process of firstly mixing the gas and storing and then filling the gas is avoided in the process; the mixed filling process can be used for avoiding the scheme that hydrogen and natural gas are firstly regulated to the same pressure and then mixed, but also can be used for using a method that low-pressure hydrogen is firstly filled and then high-pressure natural gas is filled, and a control system is used for regulating the filling proportion of hydrogen and natural gas, so that energy waste is effectively avoided. For the gas mixing and filling machine, as the gas mixing and filling functions are integrated, the pressure of two gas supply pipelines of the gas filling station is high, strong impact can occur when gas mixing and filling is carried out, pipelines and equipment are easy to vibrate, the problem that the mixing effect is not good enough, particularly the vibration problem exists, the phenomenon causes displacement of pipeline brackets and cracking of welding seams to a certain extent, and great potential safety hazards exist for a long time.

In published chinese patent application, publication No.: CN108278481a, patent name: the multi-mode fuel gas inlet and gas filling device and the gas inlet and gas filling method comprise a pre-processing system, a mixed pressurizing system and a storage and filling system; the utility model adopts the gas filling device and the gas filling method which can realize three gas filling modes (CNG, HCNG and hydrogen) of the natural gas filling station under three different gas inlet modes (pipe network natural gas, CNG trailer and LNG); the device is suitable for the construction of the HCNG gas station and the hydrogen adding station of the existing natural gas station, not only meets the requirement of the CNG automobile for gas adding, but also meets the requirement of the CNG automobile, the HCNG and the hydrogen automobile for gas adding, and is beneficial to promoting the popularization and the use of CNG (compressed natural gas), the HCNG (compressed natural gas hydrogen adding mixed gas) and the hydrogen automobile, and the cost of the automobile gas adding device is reduced. According to the utility model, a mixing device is adopted to mix CNG (compressed natural gas) and hydrogen to form HCNG (compressed natural gas hydrogen-doped mixed gas), and a pressure regulator and a flow controller in the mixing device can regulate the pressure and flow of CNG and hydrogen to output HCNG gas with specified proportion. The gas station pipelines are high-pressure pipelines, the high-pressure pipelines are used for mixing CNG and hydrogen to form HCNG, and vibration elimination of the pipelines is a technical problem which needs to be paid attention to and solved at first. For the air-entraining device of this patent (please refer to fig. 2 and the description of the prior art (this patent)), one end of the hydrogen gas inlet pipeline is connected with the air outlet of the hydrogen purifying device, and the other end of the hydrogen gas inlet pipeline is connected with the hydrogen gas inlet of the HCNG buffer tank. However, the larger volume of the buffer tank of this prior art (this patent) results in a larger footprint, and at the same time, the mixing device thereof fails to achieve a reduction in the power consumption of the hydrogen booster.

In summary, firstly, in order to solve the problems of poor mixing effect and mixing vibration of natural gas and hydrogen in the prior art (CN 105090738B); 2. in order to solve the problem that the larger volume of the buffer tank in the prior art (CN 108278481A) causes larger occupied area, the mixing device cannot reduce the power consumption of the hydrogen booster. The application is specifically proposed for solving the problem.

Disclosure of Invention

(one) solving the technical problems

Aiming at the defects of the prior art, the utility model provides a mixing device for natural gas and hydrogen, which solves the problems in the background art.

(II) technical scheme

In order to achieve the above purpose, the utility model is realized by the following technical scheme: the mixing device for the natural gas and the hydrogen comprises a first flange plate and a second flange plate, wherein an air outlet is formed in the first flange plate, an air inlet is formed in the second flange plate, a hydrogen main pipe is fixedly connected to one side wall of the first flange plate and located at the air outlet, a first buffer cavity for buffering the hydrogen is formed in the hydrogen main pipe in a ring body shape, and a sleeve component is fixedly connected to one side wall of the hydrogen main pipe, far away from the first flange plate; the second flange plate is fixedly connected with a thin-wall short pipe at the air inlet, and one end of the thin-wall short pipe, which is far away from the second flange plate, is inserted into the sleeve assembly and a gap exists between the thin-wall short pipe and the sleeve assembly; the outer sides of the thin-wall short pipe and the sleeve assembly are sleeved with expansion joint corrugated pipes, and a second buffer cavity is formed among the thin-wall short pipe, the sleeve assembly and the expansion joint corrugated pipes; the second buffer cavity is communicated with the first buffer cavity, and the air inlet is communicated with the air outlet through the cooperation of the thin-wall short pipe and the sleeve assembly and forms a channel for conveying natural gas.

Optionally, a hydrogen introduction joint for introducing hydrogen is arranged on the hydrogen main pipe, and a plurality of first through holes are formed in one side wall of the hydrogen main pipe and close to the second buffer cavity.

Optionally, one end of expansion joint bellows is fixed connection with a side wall of the hydrogen main pipe, the other end of expansion joint bellows is fixed connection with a side wall of the second flange plate, and a pressure gauge for detecting the air pressure in the second buffer cavity is arranged on the expansion joint bellows.

Optionally, the sleeve pipe subassembly includes bellows, sleeve pipe and damping baffle in respectively, the one end and the hydrogen of bellows are responsible for fixed connection in, the other end and the sleeve pipe fixed connection of bellows in, the sleeve pipe cover is established in the outside of thin wall nozzle stub and between the two clearance that is used for hydrogen to flow, damping baffle fixed mounting is including bellows and sheathed tube junction, damping baffle is whole to be coniform and its cone end towards bellows place side in, offer the second through-hole that is used for circulating natural gas, hydrogen on the damping baffle, the damping baffle adopts stainless steel metal material to make.

Optionally, the inner bellows is elastic and is capable of extending and contracting in an axial direction.

Optionally, the damping baffle is whole to be the taper, each second through-hole on the damping baffle is for setting up a plurality of centre of a circle cavitys that the size is different on the different radius circumferences that regard the center as the centre of a circle.

Optionally, each second through hole on the damping baffle is a circular hole in the center, the peripheral circular holes are sequentially increased according to the circumference, and the circular holes on the outermost ring are arranged at intervals of one large and one small.

Alternatively, the thin-walled spool 14 and sleeve assembly are both made of stainless steel metal material.

(III) beneficial effects

The utility model provides a mixing device of natural gas and hydrogen, which has the following beneficial effects:

1. according to the mixing device for natural gas and hydrogen, through the matching arrangement of the hydrogen main pipe, the expansion joint corrugated pipe and the sleeve component, the mixing device for natural gas and hydrogen has the effects of improving the mixing of natural gas and hydrogen, buffering and reducing pressure and reducing vibration, the hydrogen reaches the natural gas conveying channel after passing through the first buffer cavity of the hydrogen main pipe and the second buffer cavity in the expansion joint corrugated pipe, the hydrogen buffering and the speed reduction are realized in the first buffer cavity and the second buffer cavity, so that the pressure reduction is realized, the phenomenon of air hammer (vibration) caused by higher pressure (higher air inlet speed) when the air is introduced into a hydrogen pipeline is lightened, and the purpose of reducing the mixed vibration is achieved; the corrugated pipe buffer assembly in the sleeve assembly is utilized to generate pulsating flow, the pulsating flow strengthens the mixing effect of converging hydrogen and natural gas, so that the natural gas and the hydrogen are mixed more uniformly, and the mixing process is more convenient and efficient.

2. The mixing device can be directly embedded into the existing pipeline, the existing natural gas pipeline of the gas station is not required to be modified, power equipment is not required to be added, and hydrogen can be conveyed at lower pressure; the device adopts the matching arrangement of the hydrogen main pipe, the expansion joint corrugated pipe and the sleeve pipe assembly, so that the hydrogen injection pressure is far lower than the pressure in the natural gas pipeline, and the hydrogen is not required to be pressurized to a very high degree (the high-speed injection of the natural gas flow, the annular space passage opening can form negative pressure, the hydrogen can be sucked and ejected from the annular passage opening and pumped out); the energy transfer efficiency of the pulse jet is obviously higher than that of the constant jet, and the pulse jet can improve the heat transfer and mass transfer efficiency, and the highest energy transfer efficiency can reach 10 percent according to measurement. The device comprehensively utilizes the technical solution of high heat transfer and mass transfer efficiency of pulse flow and high mixing efficiency, and can also exert the advantages of elastic deformation of the corrugated pipe in the aspect of buffering and eliminating vibration.

3. The utility model can be arranged at the front end of the buffer tank in the prior art (CN 108278481A), not only can improve the uniform mixing of the natural gas and the hydrogen in the buffer tank, but also can greatly reduce the volume of the buffer tank and further reduce the occupied area of the buffer tank. Meanwhile, the utility model can also replace a hydrogen booster in the mixing device, and the device does not consume power, so that the power consumption of the hydrogen booster is avoided, and the aim of reducing the production cost is fulfilled.

4. The mixing device disclosed by the utility model has lower comprehensive investment cost, can replace a gas mixing and filling machine in the prior art, and simplifies equipment investment, thereby greatly reducing the construction cost of a filling station.

Drawings

FIG. 1 is a schematic perspective view of a natural gas and hydrogen mixing device according to the present utility model;

FIG. 2 is a schematic cross-sectional view of a natural gas and hydrogen mixing device according to the present utility model;

FIG. 3 is a schematic cross-sectional (arrows in the figure indicate the direction of gas flow) structural diagram of a natural gas and hydrogen mixing device according to the present utility model;

FIG. 4 is a schematic diagram of the front view of a damping baffle for a natural gas and hydrogen mixing device according to the present utility model;

FIG. 5 is a schematic perspective view of a hydrogen main pipe of a natural gas and hydrogen mixing device according to the present utility model;

fig. 6 is a schematic side view of a damping baffle for a natural gas and hydrogen mixing device according to the present utility model.

In the figure: 1. a first flange; 2. a hydrogen main pipe; 201. a first through hole; 3. a hydrogen gas introduction joint; 4. expansion joint corrugated pipe; 5. a pressure gauge; 6. a second flange; 7. an air outlet; 8. an air inlet; 9. an inner bellows; 10. damping baffle; 101. a second through hole; 11. a sleeve; 12. a first buffer chamber; 13. a second buffer chamber; 14. thin-walled short tube.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments.

Referring to fig. 1 to 6, the present utility model provides the following technical solutions: the mixing device for the natural gas and the hydrogen comprises a first flange plate 1 and a second flange plate 6, wherein an air outlet 7 is formed in the first flange plate 1, an air inlet 8 is formed in the second flange plate 6, a hydrogen main pipe 2 is fixedly connected to one side wall of the first flange plate 1 and positioned at the air outlet 7, a first buffer cavity 12 for buffering the hydrogen is formed in the hydrogen main pipe 2 in a ring shape, and a sleeve component is fixedly connected to one side wall of the hydrogen main pipe 2 far away from the first flange plate 1; the second flange plate 6 is fixedly connected with a thin-wall short pipe 14 at the air inlet 8, and one end of the thin-wall short pipe 14 far away from the second flange plate 6 is inserted into the sleeve assembly and a gap exists between the thin-wall short pipe and the sleeve assembly; the outer sides of the thin-wall short pipe 14 and the sleeve assembly are sleeved with expansion joint corrugated pipes 4, and a second buffer cavity 13 is formed among the thin-wall short pipe 14, the sleeve assembly and the expansion joint corrugated pipes 4; the second buffer cavity 13 is communicated with the first buffer cavity 12, and the air inlet 8 is communicated with the air outlet 7 through the cooperation of the thin-wall short pipe 14 and the sleeve assembly and forms a channel for conveying natural gas.

Through the matching arrangement of the hydrogen main pipe 2, the expansion joint corrugated pipe 4 and the sleeve component, the mixing device of the natural gas and the hydrogen has the effects of improving the mixing of the natural gas and the hydrogen, buffering and reducing the pressure and reducing the vibration, the hydrogen reaches the natural gas conveying channel after passing through the first buffer cavity 12 of the hydrogen main pipe 2 and the second buffer cavity 13 in the expansion joint corrugated pipe 4, and the first buffer cavity 12 and the second buffer cavity 13 realize the hydrogen buffering and the speed reduction so as to realize the pressure reduction, thereby reducing the phenomenon of air hammer (vibration) caused by higher pressure (higher pressure caused by higher air inlet speed) when the hydrogen pipeline is in air inlet, and achieving the purpose of reducing the mixed vibration; utilize bellows buffer assembly in the sleeve pipe subassembly to produce the pulsating flow, the mixing effect of the hydrogen of pulsating flow reinforcement conflux, natural gas for natural gas, hydrogen mix more evenly, and the mixing process is more convenient, high-efficient.

Specifically, the hydrogen main pipe 2 is provided with a hydrogen introduction joint 3 for introducing hydrogen, and a plurality of first through holes 201 are formed in one side wall of the hydrogen main pipe 2 and close to the second buffer chamber 13.

The hydrogen inlet connector 3 is used for being connected with a hydrogen input pipeline. Hydrogen enters the first buffer chamber 12 of the hydrogen main pipe 2 through the hydrogen lead-in connector 3, and hydrogen enters the second buffer chamber 13 through the first through hole 201 on the hydrogen main pipe 2. The inner wall surface of the expansion joint corrugated pipe 4 is in an expansion joint corrugated shape, hydrogen entering the second buffer cavity 13 can be decelerated, the flow rate of the hydrogen is reduced, the hydrogen forms a stable annular air flow to enter the second buffer cavity 13, and the stress on the gas (hydrogen) facing surface of the sleeve assembly is uniform (namely, the hydrogen flowing in a gap between the sleeve assembly and the thin-wall short pipe is uniform); meanwhile, the expansion joint corrugated pipe 4 has better compensation effect, and dampens. The expansion joint bellows 4 has a relatively thick wall thickness and can withstand high air pressure.

Specifically, one end of the expansion joint corrugated pipe 4 is fixedly connected with one side wall of the hydrogen main pipe 2, the other end of the expansion joint corrugated pipe 4 is fixedly connected with the side wall of the second flange plate 6, and the expansion joint corrugated pipe 4 is provided with a pressure gauge 5 for detecting the air pressure in the second buffer cavity 13.

Wherein the pressure gauge 5 is used for detecting the air pressure in the second buffer chamber 13. Since the expansion joint bellows 4 is made of a material having high bearing strength, and can exert a certain buffering effect by deforming at the bellows when subjected to a large air pressure. The expansion joint bellows 4 has the following functions and effects: firstly, the pressure impact of the pipeline air flow can be effectively buffered, and the stability of the cooperation between the structures is ensured; secondly, the inner wall surface of the built-in corrugated pipe is provided with convex-concave wrinkles, turbulence of air flow is increased, and hydrogen is favorable for being uniformly mixed. Meanwhile, the corrugated pipe body bears two paths of opposite airflow pulling forces, and the equal parts counteract each other, so that the corrugated pipe is not damaged due to excessive deformation, and the service life of the corrugated pipe is prolonged. The aperture size of the first through hole 201 on the hydrogen main pipe 2 is set according to specific implementation conditions, the aperture size is convenient for the adaptive adjustment of hydrogen flow, and the adjustment of the aperture is used for realizing the adjustment of air flow parameters. The expansion joint bellows 4 may be a commercially available expansion joint bellows.

Specifically, the sleeve assembly comprises an inner corrugated pipe 9, a sleeve 11 and a damping baffle 10, one end of the inner corrugated pipe 9 is fixedly connected with the hydrogen main pipe 2, the other end of the inner corrugated pipe 9 is fixedly connected with the sleeve 11, the sleeve 11 is sleeved outside the thin-wall short pipe 14, a gap for hydrogen to flow exists between the sleeve and the sleeve, the damping baffle 10 is fixedly installed at the joint of the inner corrugated pipe 9 and the sleeve 11, a second through hole 101 for circulating natural gas and hydrogen is formed in the damping baffle 10, the conical outlet end of the damping baffle is arranged backwards, and the damping baffle 10 is made of stainless steel metal materials.

More specifically, the damping baffle 10 is in a cone shape as a whole, and each second through hole 101 on the damping baffle 10 is a plurality of circle center hollows with different sizes and arranged on circumferences with different radiuses and with the center as the circle center. Each second through hole 101 on the damping baffle 10 is a circular hole in the center, the circular holes on the periphery are sequentially enlarged according to the circumference, and the circular holes on the outermost ring are arranged at intervals of one large to one small. The second through holes 101 on the damping diaphragm 10 are a plurality of circular holes with uniform intervals and the same size. Each second through hole 101 on the damping baffle 10 is a plurality of circle center hollows with different sizes and arranged on circumferences with different radiuses and center centers. Wherein, damping baffle 10 is used with interior bellows 9 cooperation to damping baffle 10 cover is established and is installed in the one end of bellows 9.

Wherein the arrangement of the sleeve assembly, i.e. the cooperation of the inner bellows 9, the damping baffle 10 and the sleeve 11, serves to buffer and eliminate resonance. The resonance elimination is achieved while the high-efficiency uniform mixing is obtained only by means of the airflow kinetic energy of the pipeline without inputting external energy, and the prior art is difficult to achieve. The mixing device has the dual effects of efficient uniform mixing and resonance elimination. Meanwhile, the damping baffle plate 10 is arranged on the inner corrugated pipe 9, so that the key for generating pulse flow is that the pulse flow is generated by fully utilizing the self-excitation of the airflow kinetic energy of the pipelines (the inner corrugated pipe 9, the sleeve 11 and the damping baffle plate 10) through the telescopic movement of the inner corrugated pipe 9 (the telescopic movement is repeatedly performed under the pushing of airflow), the heat and mass transfer efficiency of the pulse flow is high, the mixing efficiency of natural gas and hydrogen are promoted, and the mixing efficiency is high.

Specifically, the thin-walled spool piece 14 and sleeve assembly are each made of stainless steel metal material. The inner bellows 9 is elastic and can be folded and contracted in the axial direction. The thin-walled nipple 14 is made of stainless steel metal. The wall thickness of the sleeve 11 and the damping diaphragm 10 is thin.

The inner bellows 9 may be made of a material having an elastic deformation characteristic, preferably a 304 stainless steel material, which is deformed by compression and then is stretched, i.e. is stretched by contraction. Kinetic energy in the gas flowing along the channel is converted into energy of pressure waves. In a straight tube the pressure wave moves laterally along the channel, whereas if the tube is curved the shock wave bounces off the wall. In a curved channel the pressure wave eventually propagates along the channel and the time required to move along the pipe may increase. Because the air hammer frequency is very high, the shock wave or transient reverse response caused by the air hammer effect is directly applied to the inner corrugated pipe 9 or the expansion joint corrugated pipe 4, so that the vibration frequencies and the vibration directions of the two corrugated pipes are not completely consistent and even are opposite to each other, the two corrugated pipes are mutually restrained, the damping effect generated by the two corrugated pipes is large, and the shock energy suddenly rising in air pressure can be quickly absorbed and dissipated. The thin-wall short pipe 14 and the inner bellows 9 are preferably made of 304 stainless steel, the wall thickness of the thin-wall short pipe is thinner, and the thin-wall short pipe has strong corrosion resistance and hydrogen embrittlement resistance under the condition of meeting the material strength.

The sleeve 11 and the damping baffle 10 have certain weight, the sleeve 11 and the damping baffle 10 are arranged at the front end air inlet end of the inner bellows 9, the sleeve and the inner bellows 9 form a spring mass system similar to a piston and a spring, and when the spring mass system in a zero initial condition receives constant exciting force of airflow, the exciting force can be regarded as superposition of a series of equivalent pulse forces. When the combined flow of natural gas and hydrogen passes through the damper holes 101 in the damper diaphragm 10, the magnitude of the force applied to the damper diaphragm 10 changes with the change of the inlet and outlet momentum thereof. That is, the inner bellows 9 with the sleeve 11 is excited by a constant acting force of a constant air flow to perform sinusoidal simple harmonic motion, and the air flow pressure in the cavity of the inner bellows 9 is periodically changed in sinusoidal simple harmonic motion, so that pulsating air flow is generated. The stiffness of the inner bellows 9 can be adjusted according to actual needs, so that the stiffness of the combined spring-like piston system is selectable, thereby changing the natural frequency of the spring-like mass system, and also changing the frequency of the pulsating gas flow. Therefore, the self-excitation of the gas is realized, the energy consumption is small, the structure is simple, the adjustment is convenient, the cost is low, the operation safety is durable, and the pulsating gas flow parameters can be adjusted.

When in use, the utility model is characterized in that: the device shown in the application is arranged on a pipeline for preparing natural gas and hydrogen to be mixed, the gas outlet end of the natural gas pipeline is fixedly arranged at the position of the gas inlet 8 and the second flange plate 6 of the device shown in the application, the gas outlet end of the hydrogen pipeline (hydrogen input) is fixedly arranged at the position of the gas outlet 7 and the hydrogen leading-in joint 3 of the device shown in the application, and the gas inlet end of equipment (or pipeline) for outputting mixed gas is fixedly arranged at the position of the gas outlet 7 and the first flange plate 1.

Natural gas enters the device from the gas inlet 8 and flows towards the direction of the gas outlet 7. During this time, the flow passes through the thin-walled short pipe 14, the damper separator 10 (through each of the second through holes 101 in the damper separator 10), the inner bellows 9, the middle hole of the hydrogen main pipe 2, and the gas outlet 7 in this order.

Hydrogen enters the device from the hydrogen lead-in connector 3 and flows towards the direction of the air outlet 7. During the process, the natural gas flows through the first buffer chamber 12, the first through hole 201, the second buffer chamber 13, the gap between the sleeve 11 and the thin-walled short tube 14 in the hydrogen main pipe 2, and then flows into the natural gas flowing main channel to mix with the natural gas in a converging manner, the damping diaphragm 10 (flows through each second through hole 101 on the damping diaphragm 10), the inner bellows 9, the middle hole of the hydrogen main pipe 2, and the gas outlet 7 (please refer to fig. 3 of the specification).

The existing gas station adopts a premixing technology, a storage tank of HCNG mixed gas is often needed, and the HCNG mixed gas can be layered to cause uneven density in the long-term storage process, and the combustion and emission characteristics of an automobile are affected after the HCNG mixed gas is filled into an HCNG vehicle. The mixing device can solve the problem of uneven density caused by gas layering of the existing gas station. Not only greatly improves the mixing condition of the gases and improves the turbulent flow diffusion capability of the gases, but also ensures that the two gases are fully and uniformly mixed, and can effectively solve the problem of uneven density caused by layering of the gases.

The utility model is characterized in that the utility model can eliminate the vibration of the pipeline. The expansion joint corrugated pipe has good compensation effect, and can absorb vibration and reduce noise. The device has the advantages of small volume, small occupied area, simple structure, convenient installation and disassembly, and time and labor saving. The movable mounting part and the wearing part are not needed, the manufacturing process is simple, the cost is low, the installation and the use are convenient, the practicability is high, the cost performance is high, and the large-scale popularization and the application are easy.

The foregoing is only a preferred embodiment of the present utility model, but the scope of the present utility model is not limited thereto, and any person skilled in the art, who is within the scope of the present utility model, should make equivalent substitutions or modifications according to the technical scheme of the present utility model and the inventive concept thereof, and should be covered by the scope of the present utility model.

Claims (8)

1. A mixing arrangement of natural gas and hydrogen, characterized in that: the hydrogen gas main pipe comprises a first flange plate (1) and a second flange plate (6), wherein an air outlet (7) is formed in the first flange plate (1), an air inlet (8) is formed in the second flange plate (6), a hydrogen main pipe (2) is fixedly connected to one side wall of the first flange plate (1) and located at the air outlet (7), a first buffer cavity (12) for buffering hydrogen is formed in the hydrogen main pipe (2) in a ring shape, and a sleeve component is fixedly connected to one side wall of the hydrogen main pipe (2) far away from the first flange plate (1); the second flange plate (6) is fixedly connected with a thin-wall short pipe (14) at the air inlet (8), and one end, far away from the second flange plate (6), of the thin-wall short pipe (14) is inserted into the sleeve assembly and a gap exists between the thin-wall short pipe and the sleeve assembly; the expansion joint corrugated pipe (4) is sleeved outside the thin-wall short pipe (14) and the sleeve assembly, and a second buffer cavity (13) is formed among the thin-wall short pipe (14), the sleeve assembly and the expansion joint corrugated pipe (4); the second buffer cavity (13) is communicated with the first buffer cavity (12), and the air inlet (8) is communicated with the air outlet (7) through the matching of the thin-wall short pipe (14) and the sleeve assembly and forms a channel for conveying natural gas.

2. A natural gas and hydrogen mixing device according to claim 1, wherein: the hydrogen main pipe (2) is provided with a hydrogen lead-in connector (3) for leading in hydrogen, and a plurality of first through holes (201) are formed in one side wall of the hydrogen main pipe (2) and close to the second buffer cavity (13).

3. A natural gas and hydrogen mixing device according to claim 1, wherein: one end of the expansion joint corrugated pipe (4) is fixedly connected with one side wall of the hydrogen main pipe (2), the other end of the expansion joint corrugated pipe (4) is fixedly connected with the side wall of the second flange plate (6), and a pressure gauge (5) for detecting air pressure in the second buffer cavity (13) is arranged on the expansion joint corrugated pipe (4).

4. A natural gas and hydrogen mixing device according to claim 1, wherein: the sleeve assembly comprises an inner corrugated pipe (9), a sleeve (11) and a damping partition plate (10), one end of the inner corrugated pipe (9) is fixedly connected with a hydrogen main pipe (2), the other end of the inner corrugated pipe (9) is fixedly connected with the sleeve (11), the sleeve (11) is sleeved outside a thin-wall short pipe (14) and is provided with a gap for hydrogen to flow, the damping partition plate (10) is fixedly mounted at the joint of the inner corrugated pipe (9) and the sleeve (11), the damping partition plate (10) is integrally tapered, the taper end of the damping partition plate faces the side of the inner corrugated pipe (9), a second through hole (101) for circulating natural gas and hydrogen is formed in the damping partition plate (10), and the damping partition plate (10) is made of stainless steel metal materials.

5. A natural gas and hydrogen mixing device according to claim 4, wherein: the inner bellows (9) is elastic and can extend and retract in the axial direction.

6. A natural gas and hydrogen mixing device according to claim 4, wherein: and each second through hole (101) on the damping partition plate (10) is a plurality of circle center holes with different sizes and arranged on circumferences with different radiuses and with the center as the circle center.

7. A natural gas and hydrogen mixing device according to claim 6, wherein: each second through hole (101) on the damping partition plate (10) is a round hole in the center, round holes in the periphery are sequentially enlarged according to the circumference, and round holes in the outermost ring are arranged at intervals of one large size and one small size.

8. A natural gas and hydrogen mixing device according to claim 1, wherein: the thin-wall short tube (14) and the sleeve component are made of stainless steel metal materials.