Safe gas mixing device and application thereof in high-concentration hydrogen mixing field

Abstract

The invention discloses a safe gas mixing device and application thereof in the field of high-concentration hydrogen mixing. The gas mixing device is suitable for mixing hydrogen with the volume purity larger than or equal to 99.99% and combustion-supporting gas, and the combustion-supporting gas is selected from at least one of air and oxygen. The gas mixing device comprises a tank body, a gas mixing unit, a gas distribution plate, a hydrogen inlet unit, a combustion-supporting gas inlet unit, a catalyst setting unit, a temperature measuring unit and a mixed gas outlet unit. When the gas mixing device is used for mixing high-concentration hydrogen and air (or oxygen), due to reasonable structural layout and metal filler filling in the device, not only can the gas be uniformly mixed, but also the explosion risk can be fully reduced. The device and the method are simple and easy to operate, good in effect, low in cost and high in safety, and can be applied to the hydrogen catalytic combustion process.

Description

Technical Field

[0001] The invention belongs to the field of hydrogen energy technology application, and in particular relates to a safe gas mixing device and its application in the field of high-concentration hydrogen mixing and in a hydrogen combustion catalytic process. Background Art

[0002] Hydrogen is an ideal clean energy with high energy density. It can not only be used for power generation and energy storage, but also for heating through combustion. Therefore, it has broad application prospects in aerospace, industrial production, transportation and civil fields. As we all know, hydrogen is a flammable and explosive gas with a minimum ignition energy of only 0.017mJ. The explosion limit range in air is 4-75% (volume), and the explosion limit range in oxygen is 4.7-94% (volume). When high-concentration hydrogen (such as industrial pure hydrogen, with a concentration of 99.99% (volume)) is directly mixed with air (or oxygen) as fuel, the hydrogen concentration will experience a change from high to low. In order to achieve full combustion of hydrogen, the volume concentration of hydrogen in the air (or oxygen) mixture needs to be controlled below 29.5% (or 66.6%), so it will inevitably enter the explosion limit range of hydrogen, which is very likely to cause an explosion accident. The use of hydrogen catalytic combustion technology can make hydrogen burn flamelessly under the action of a catalyst, with good safety and no NOx exhaust gas emissions. It has been widely used in technical fields such as heating. However, when applying hydrogen catalytic combustion technology, there is still the problem of explosion risk caused by mixing high-concentration hydrogen with air (or oxygen).

[0003] Utility model patent CN215570436U discloses a hydrogen catalytic burner, which allows air and hydrogen to enter the reaction chamber through an air pipeline and a hydrogen pipeline respectively, to react with the catalyst, and to transfer the heat released by the reaction to the heat transfer oil for thermal utilization. However, it ignores the problem of explosion risk when hydrogen and air are mixed in the reaction chamber.

[0004] Invention patent CN110282600A discloses a dehydrogenation device based on hydrogen catalytic combustion heating, in which hydrogen and air are introduced into a gas mixing chamber for full mixing, and then the mixed gas is passed into a dehydrogenation tank. The patent also fails to consider the explosion risk during the mixing process of hydrogen and air, and therefore does not propose a targeted solution.

[0005] The purpose of the present invention is to provide a device for safely mixing high-concentration hydrogen with air (and / or oxygen) in the technical field of hydrogen catalytic combustion, in order to effectively reduce the potential explosion risk in the process of mixing hydrogen and air. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art, provide a device for safely mixing high-concentration hydrogen with air (or oxygen), and reduce the risk of explosion. The gas mixing device comprises a tank body, a gas mixing unit, a gas distribution plate, a hydrogen intake unit, a combustion-supporting gas intake unit, a catalyst setting unit, a temperature measurement unit, and an outlet unit for the mixed gas; when the gas mixing device is used to mix high-concentration hydrogen with air (or oxygen), due to the reasonable structural layout and metal filler filling inside the device, not only can the gas be mixed evenly, but also the risk of explosion can be fully reduced. The device and method are simple and easy to operate, have good effects, low costs, and high safety, and can be applied to the process of hydrogen catalytic combustion.

[0007] The present invention is achieved through the following technical solutions:

[0008] On the one hand, the present invention provides a safe gas mixing device, which is suitable for mixing hydrogen with a volume purity of ≥99.99% and a combustion-supporting gas.

[0009] Preferably, the present invention provides a safe gas mixing device, wherein the combustion-supporting gas is selected from at least one of air and oxygen.

[0010] Preferably, the present invention provides a safe gas mixing device, which comprises a tank body, a gas mixing unit, a gas distribution plate, a hydrogen gas inlet unit, a combustion-supporting gas inlet unit, a catalyst setting unit, a temperature measuring unit and a mixed gas outlet unit;

[0011] in:

[0012] The gas mixing unit, the gas distribution plate, the hydrogen inlet unit, the combustion-supporting gas inlet unit, the catalyst setting unit, the temperature measuring unit and the mixed gas outlet unit are all arranged in the tank body;

[0013] The gas mixing unit is filled with metal fillers;

[0014] The gas distribution plate is located between the gas mixing unit and the catalyst setting unit or in the gas mixing unit;

[0015] The hydrogen intake unit comprises a hydrogen intake pipeline and a nozzle located at the end of the hydrogen intake pipeline.

[0016] Preferably, the present invention provides a safe gas mixing device, wherein the gas distribution plate is a stainless steel wire mesh with a thickness of 1-5 mm, a pore diameter of 1-300 μm, and an opening rate of ≥90%.

[0017] Preferably, the present invention provides a safe gas mixing device, wherein the metal filler is selected from stainless steel triangular spiral filler or Dixon filler, and the size of the filler is 2 mm×2 mm.

[0018] Preferably, the present invention provides a safe gas mixing device, wherein the volume ratio of the gas mixing unit to the volume of the tank body is 0.05-0.5.

[0019] Preferably, the present invention provides a safe gas mixing device, wherein the nozzle is made of stainless steel, has a pore size of 0.1-0.5 mm, an applicable flow rate of 0-5 L / min, a temperature range of -30-300°C, and a pressure of 0.1-10 MPa.

[0020] Preferably, the present invention provides a safe gas mixing device, wherein the ratio of the number of nozzles to the flow rate of the hydrogen intake unit is 0.2-5 nozzles / L / min.

[0021] Preferably, the present invention provides a safe gas mixing device, wherein the nozzle is located at 1 / 4-2 / 3 of the gas mixing unit.

[0022] Preferably, the present invention provides a safe gas mixing device, wherein the hydrogen gas intake unit and the combustion-supporting gas intake unit can be arranged at the same position of the tank body, or can be arranged at different positions of the tank body respectively.

[0023] Preferably, the present invention provides a safe gas mixing device, wherein the hydrogen gas intake unit is located at the bottom of the tank body, and the combustion-supporting gas intake unit is located at the side of the tank body at a distance of 0.5-2 cm from the bottom of the tank body.

[0024] Preferably, the present invention provides a safe gas mixing device, wherein the combustion-supporting gas unit is located between the gas mixing unit and the catalyst setting unit, and the volume ratio of the combustion-supporting gas unit to the gas mixing unit is 1.5-4.

[0025] Preferably, the present invention provides a safe gas mixing device, wherein the hydrogen intake unit and the combustion-supporting gas intake unit are arranged at the same position at the bottom of the tank body, and the hydrogen intake pipeline of the hydrogen intake unit and the combustion-supporting gas intake pipeline of the combustion-supporting gas intake unit adopt a sleeve form, wherein the hydrogen intake pipeline is a tube side, and the combustion-supporting gas intake pipeline is a shell side.

[0026] On the other hand, the present invention also provides the use of the above-mentioned gas mixing device in a hydrogen combustion catalytic process.

[0027] Preferably, the present invention further provides the above-mentioned gas mixing device for mixing hydrogen and air, and the volume concentration of hydrogen in the mixed gas of hydrogen and air after mixing by the gas mixing device is 4-29.5%.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The device for mixing hydrogen and air (or oxygen) described in the present invention is particularly suitable for occasions with high concentration hydrogen (such as volume purity ≥99.99%), for example, catalytic combustion when the volume concentration of hydrogen in the air (or oxygen) mixture is 4-29.5% (or 4.7-66.6%); using high concentration hydrogen (such as volume purity ≥99.99%) for catalytic combustion heat supply is not only conducive to providing more heat, but also can reduce the volume of the device and reduce the equipment cost.

[0030] The device for mixing high-concentration hydrogen (such as volume purity ≥ 99.99%) with air (or oxygen) of the present invention has a simple and compact structure, low cost, good gas mixing effect and high safety. When high-concentration hydrogen (such as volume purity ≥ 99.99%) is mixed with air (or oxygen), a free radical chain reaction may occur between hydrogen and oxygen free radicals, which can easily cause an explosion. According to the flame quenching theory, a narrow channel is not conducive to the spread of flames. At the same time, the channel wall can capture free radicals, reduce the probability of free radicals continuing to participate in the chain reaction, and reduce the risk of explosion.

[0031] The gas mixing device of the present invention, on the one hand, controls the height of the mixing chamber to limit the volume of the mixing chamber, thereby reducing the mixing space of hydrogen and air (or oxygen) as much as possible and shortening the contact time between the two; on the other hand, the gas is dispersed by properly setting the position of the gas distribution plate to achieve the purpose of mixing the two gases evenly. The filled metal filler plays an important role in the mixing device. It not only occupies part of the volume of the mixing chamber space, reduces the actual mixing space of hydrogen and air (or oxygen), and reduces the concentration of free radical generation, but also has a small-particle metal wire roll structure with large pores and can fill the entire mixing chamber, which can disperse the gas and improve the mixing uniformity; at the same time, the filled small-particle metal wire roll forms a narrow channel by separating the mixing chamber space, which is conducive to inhibiting the generation of free radicals.

[0032] All devices of the present invention have simple structures, the gas distribution plates and metal fillers used are commercially available products, and the selected stainless steel is a common material, so the manufacturing cost is low;

[0033] By controlling the volume of the mixing chamber and using metal fillers to divide and form narrow channels, the probability of free radical formation is reduced and the risk of explosion is reduced, thus improving safety.

[0034] The mixing device of the present invention is applied to high-concentration hydrogen (e.g., volume purity ≥

[0035] 99.99%) during catalytic combustion, it can be used Figure 1 , Figure 2 or Figure 3 The technical solution shown in FIG. Figure 1 , Figure 2In the scheme shown, hydrogen and air (or oxygen) are introduced into the tank at different locations, which is safer. An additional air (oxygen) chamber is added, which is beneficial to improving the distribution of air (oxygen) and the uniformity of mixing with hydrogen. However, the volume of the tank is increased and the cost is slightly higher.

[0036] use Figure 3 In the scheme shown, no air (oxygen) chamber is set, the tank body is small in size and the cost is slightly lower, but hydrogen and air (or oxygen) are inhaled at the same part of the tank body, and the probability of collision between the two high-speed airflows is high, which poses certain safety risks. Therefore, it is necessary to limit the distance between the position of the hydrogen nozzle and the upper end of the air (or oxygen) inlet pipe. If the distance is too short, the safety risk is high, and if the distance is too long, the volume of the mixing chamber increases. The safety mentioned above can be detected by thermocouple temperature measurement.

[0037] like Figure 1 , Figure 2 and Figure 3 As shown, a thermocouple is placed just above the hydrogen nozzle and at the top of the gas mixing chamber. If the hydrogen and air (oxygen) entering at room temperature (25°C) cause a temperature rise due to mixing, for example, exceeding 50°C, it indicates that a certain degree of gas-phase free radical reaction has occurred between hydrogen and oxygen, so there is a safety risk caused by the runaway reaction. The more significant the temperature rise, the greater the safety risk. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 Schematic diagram of the mixing device in Example 1, Example 2, Comparative Example 1 and Comparative Example 3;

[0039] Figure 2 is a schematic diagram of the mixing device in Example 3;

[0040] Figure 3 Schematic diagram of the mixing device in Example 4, Example 5, Comparative Example 2 and Comparative Example 4;

[0041] Figure 4 Schematic diagram of the mesh-shaped gas distribution plate used in Examples 1-5 and Comparative Examples 1-4;

[0042] Figure 5 This is a side view of the hydrogen nozzle of the mixing device in Example 3. DETAILED DESCRIPTION

[0043] The technical solution of the present invention will be further described in detail below through embodiments and drawings, but the protection scope of the present invention shall not be limited thereto.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those of ordinary skill in the art to which the invention belongs. Although any methods and materials similar or equivalent to those described herein can be used to implement or test the present invention, preferred methods and materials are described herein. For purposes of the present invention, the following terms are defined below.

[0045] As used herein, the term "about" refers to an amount, level, value, dimension, size, or amount that differs by up to 30%, 20%, or 10% compared to the amount, level, value, dimension, size, or amount of a reference product. Percentages used herein, unless otherwise indicated, are by weight.

[0046] Throughout the specification and claims, unless otherwise required, the following words "comprise" and variations "comprising" and "including" will be understood to imply the inclusion of a stated integer or step, or a group of integers or steps, but not the exclusion of any other integer or step, or other group of integers or steps.

[0047] Experimental Materials:

[0048]

[0049] The experimental methods in the following examples without specifying specific conditions are usually carried out under conventional conditions or according to the conditions recommended by the manufacturer. Unless otherwise defined, all professional and scientific terms used in the text have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein can be applied to the methods of the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only.

[0050] Embodiment 1:

[0051] Hydrogen with a flow rate of 1 L / min and a volume purity of 99.99% at room temperature and air at 4 L / min (the volume concentration of hydrogen after mixing the two is 20%) are respectively Figure 1 The bottom and side of the metal tank shown are introduced into the interior of the tank, and the diameter of the tank is 3 cm. The air first enters the air chamber filled with triangular spiral metal filler, with a height of 2 cm, and then enters the gas mixing chamber from the gas distribution plate. The mixing chamber is also filled with triangular spiral metal filler, with a height of 5 cm. Due to the presence of the filler, the air is disturbed when passing through, and the airflow is dispersed. Hydrogen is ejected through the air inlet pipe and nozzle, and the top of the nozzle is 2 cm away from the gas distribution plate. The ejected hydrogen meets and mixes with the air in the upper space of the mixing chamber, and then enters the catalyst bed together. Since hydrogen and air are mixed in the gap of the metal filler, the good dispersion makes the mixing uniform, and the narrow contact space reduces the risk of free radical generation and has good safety. The temperature measured by the thermocouple shows that it is lower than 35°C.

[0052] Embodiment 2:

[0053] Hydrogen with a flow rate of 1 L / min and a volume purity of 99.999% at room temperature and oxygen with a volume purity of 99.5% at a flow rate of 4 L / min (the volume concentration of hydrogen after the two are mixed is 20%) are respectively Figure 1 The bottom and side of the metal tank shown are introduced into the interior of the tank, and the diameter of the tank is 3 cm. Oxygen first enters the oxygen chamber filled with Dixon metal filler, with a height of 4 cm, and then enters the gas mixing chamber from the gas distribution plate. The mixing chamber is also filled with Dixon metal filler, with a height of 8 cm. Due to the presence of the filler, the oxygen is disturbed when passing through, and the airflow is dispersed. Hydrogen is ejected through the air inlet pipe and the nozzle, and the top of the nozzle is 3 cm away from the gas distribution plate. The ejected hydrogen and oxygen meet and mix in the upper space of the mixing chamber, and then enter the catalyst bed together. Since hydrogen and oxygen are mixed in the gap of the metal filler, the good dispersion makes the mixing uniform, and the narrow contact space reduces the risk of free radical generation and has good safety. The temperature measured by the thermocouple shows that it is lower than 40°C.

[0054] Embodiment 3:

[0055] Hydrogen with a flow rate of 5 L / min and a volume purity of 99.99% at room temperature and oxygen with a volume purity of 99.5% at 5 L / min (the volume concentration of hydrogen after mixing the two is 50%) are respectively supplied from Figure 2 The bottom and side of the metal tank shown are introduced into the interior of the tank, and the diameter of the tank is 8 cm. Oxygen first enters the oxygen chamber filled with triangular spiral metal filler, with a height of 4 cm, and then enters the gas mixing chamber from the gas distribution plate. The mixing chamber is also filled with triangular spiral metal filler, with a height of 8 cm. Hydrogen is ejected through the air inlet pipe and 5 nozzles, and the top of the nozzle is 4 cm away from the gas distribution plate. The ejected hydrogen and oxygen meet and mix in the upper space of the mixing chamber, and then enter the catalyst bed together. Since hydrogen and oxygen are mixed in the gap of the metal filler, the good dispersion makes the mixing uniform, and the narrow contact space reduces the risk of free radical generation and has good safety. The temperature measured by the thermocouple shows that it is lower than 50°C.

[0056] Embodiment 4:

[0057] Hydrogen with a flow rate of 1 L / min and a volume purity of 99.99% at room temperature and air at 5 L / min (the volume concentration of hydrogen after mixing the two is 16.7%) are respectively Figure 3The bottom of the metal tank shown is introduced into the tank in the form of a concentric sleeve. Hydrogen goes through the tube and air goes through the shell. The diameter of the tank is 4 cm. The gas mixing chamber inside the tank is filled with Dixon metal filler, which is 6 cm high. The top of the hydrogen nozzle is 3 cm away from the upper end of the air inlet pipe. The ejected hydrogen and air meet and mix in the upper space of the mixing chamber, and then pass through the gas distribution plate into the catalyst bed. Since hydrogen and air are mixed in the gap of the metal filler, the dispersion is good, making the mixing uniform, and the contact space is narrow, which reduces the risk of free radical generation and has good safety. The temperature measured by the thermocouple shows that it is lower than 40°C.

[0058] Embodiment 5:

[0059] Hydrogen with a flow rate of 3 L / min and a volume purity of 99.999% at room temperature and 3 L / min of oxygen (the volume concentration of hydrogen after the two are mixed is 50%) is added from Figure 3 The bottom of the metal tank shown is introduced into the tank in the form of three concentric sleeves. Hydrogen goes through the tube and oxygen goes through the shell. The diameter of the tank is 6 cm. The gas mixing chamber inside the tank is filled with triangular spiral metal fillers with a height of 8 cm. The top of the hydrogen nozzle is 4 cm away from the upper end of the oxygen inlet pipe. The ejected hydrogen and oxygen meet and mix in the upper space of the mixing chamber, and then pass through the gas distribution plate into the catalyst bed. Since hydrogen and oxygen are mixed in the gap of the metal filler, the space is narrow and the contact time is short, which reduces the risk of free radical generation and has good safety. The temperature measured by the thermocouple shows that it is lower than 50°C.

[0060] Comparative Example 1: (Compared with Example 2, the metal fillers in the oxygen chamber and the gas mixing chamber are eliminated)

[0061] Hydrogen with a flow rate of 1 L / min and a volume purity of 99.999% at room temperature and oxygen with a volume purity of 99.5% at a flow rate of 4 L / min (the volume concentration of hydrogen after the two are mixed is 20%) are respectively Figure 1 The bottom and side of the metal tank shown are introduced into the tank, and the diameter of the tank is 3 cm. Oxygen passes through the oxygen chamber and enters the gas mixing chamber from the gas distribution plate. The height of the mixing chamber is 8 cm. Since there is no filler in the oxygen chamber and the gas mixing chamber, the airflow dispersion is poor when oxygen passes through. Hydrogen is ejected through the air inlet pipe and the nozzle, and the top of the nozzle is 3 cm away from the gas distribution plate. The ejected hydrogen and oxygen meet and mix in the upper space of the mixing chamber, and then enter the catalyst bed together. Since there is no metal filler to disperse the airflow when hydrogen and oxygen are mixed, the mixing uniformity is poor. At the same time, when high-concentration hydrogen and oxygen are directly mixed, free radicals are easily generated, and the safety is poor. The temperature measured by the thermocouple shows that if it is higher than 100°C, the hydrogen inlet valve must be closed immediately to prevent accidents.

[0062] Comparative Example 2: (Compared with Example 4, the metal filler in the gas mixing chamber is eliminated) Hydrogen with a flow rate of 1 L / min and a volume purity of 99.99% at room temperature and 5 L / min of air (the volume concentration of hydrogen after the two are mixed is 16.7%) are respectively Figure 3 The bottom of the metal tank shown is introduced into the tank in the form of a concentric sleeve. Hydrogen goes through the tube and air goes through the shell. The diameter of the tank is 4 cm. The height of the gas mixing chamber inside the tank is 6 cm, and there is no metal filler. The top of the hydrogen nozzle is 3 cm away from the upper end of the air inlet pipe. The ejected hydrogen and air meet and mix in the upper space of the mixing chamber, and then pass through the gas distribution plate to enter the catalyst bed. Since there is no metal filler to disperse the air flow when hydrogen and air are mixed, the mixing uniformity is poor. At the same time, when high-concentration hydrogen and air are directly mixed, free radicals are easily generated, and the safety is poor. The temperature measured by the thermocouple shows that if it is higher than 100°C, the hydrogen inlet valve must be closed immediately to prevent accidents.

[0063] Comparative Example 3: (Compared with Example 2, the height of the gas mixing chamber is 10 cm)

[0064] Hydrogen with a flow rate of 1 L / min and a volume purity of 99.999% at room temperature and oxygen with a volume purity of 99.5% at a flow rate of 4 L / min (the volume concentration of hydrogen after the two are mixed is 20%) are respectively Figure 1 The bottom and side of the metal tank shown are introduced into the interior of the tank, and the diameter of the tank is 3 cm. Oxygen first enters the oxygen chamber filled with Dixon metal filler, with a height of 4 cm, and then enters the gas mixing chamber from the gas distribution plate. The mixing chamber is also filled with Dixon metal filler, with a height of 10 cm. Hydrogen is ejected through the air inlet pipe and nozzle, and the top of the nozzle is 3 cm away from the gas distribution plate. The ejected hydrogen and oxygen meet and mix in the upper space of the mixing chamber, and then enter the catalyst bed together. Due to the increase in the height of the mixing chamber, the contact time between hydrogen and oxygen increases, which increases the risk of the two producing free radicals and thus causing a gas phase chain reaction, and the safety is reduced. The temperature measured by the thermocouple shows that it is higher than 60°C.

[0065] Comparative Example 4: (Compared with Example 4, the height of the gas mixing chamber is 4 cm)

[0066] Hydrogen with a flow rate of 1 L / min and a volume purity of 99.99% at room temperature and air at 5 L / min (the volume concentration of hydrogen after mixing the two is 16.7%) are respectively Figure 3The bottom of the metal tank shown is introduced into the tank in the form of a concentric sleeve. Hydrogen goes through the tube and air goes through the shell. The diameter of the tank is 4 cm. The gas mixing chamber inside the tank is filled with Dixon metal filler with a height of 4 cm. The top of the hydrogen nozzle is 3 cm away from the upper end of the air inlet pipe. The ejected hydrogen and air meet and mix in the upper space of the mixing chamber, and then pass through the gas distribution plate to enter the catalyst bed. Due to the insufficient height of the mixing chamber, the uniformity of the mixing of hydrogen and air is reduced. The temperature measured by the thermocouple shows that it is higher than 60°C.

[0067] Test Example 1: Gas Mixing Uniformity

[0068] Test samples: Mixed gases of Examples 1-5 and mixed gases of Comparative Examples 1-4

[0069] Chromatographic model: Clarus 580, chromatographic column: Porapak Q packed column, manufacturer: Perkin Elmer, USA.

[0070] Gas chromatography analysis process:

[0071] (1) Using thermal conductivity detector, detector temperature: 100 °C, chromatographic column box temperature: 50 °C, carrier gas: nitrogen, carrier gas flow rate: 30 ml / min;

[0072] (2) The external standard method is used for quantitative calculation, that is, hydrogen standard samples of different concentrations are injected and analyzed, and the hydrogen concentration is correlated with the hydrogen chromatographic peak area to draw a standard curve.

[0073] (3) Detection of unknown gas samples: Place one end of the sampling pipe into the part to be detected in the tank, and connect the other end to the chromatographic gas inlet. Then, the sample can be injected for analysis to measure the hydrogen concentration.

[0074] like Figure 1 , Figure 2 and Figure 3 As shown, three sampling locations are set at the junction of the catalyst bed and the metal filler. The following table summarizes the sampling and analysis of the mixed gas in each embodiment and comparative example:

[0075]

[0076]

[0077] As can be seen from the above table, the uniformity of gas mixing can be obtained by sampling and analyzing different parts. For example, the concentration of hydrogen in the gas is detected by gas chromatography analysis. The closer the hydrogen concentrations in different parts are, the better the uniformity of gas mixing.

Claims

1. A safe gas mixing device, characterized in that: The gas mixing device is suitable for mixing hydrogen with a volume purity of ≥99.99% and a combustion-supporting gas.

2. The gas mixing device according to claim 1, characterized in that: The combustion-supporting gas is selected from at least one of air and oxygen.

3. The gas mixing device according to claim 1, characterized in that: The gas mixing device comprises a tank body, a gas mixing unit, a gas distribution plate, a hydrogen gas inlet unit, a combustion-supporting gas inlet unit, a catalyst setting unit, a temperature measuring unit and a mixed gas outlet unit; in: The gas mixing unit, the gas distribution plate, the hydrogen inlet unit, the combustion-supporting gas inlet unit, the catalyst setting unit, the temperature measuring unit and the mixed gas outlet unit are all arranged in the tank body; The gas mixing unit is filled with metal fillers; The gas distribution plate is located between the gas mixing unit and the catalyst setting unit or in the gas mixing unit; The hydrogen intake unit comprises a hydrogen intake pipeline and a nozzle located at the end of the hydrogen intake pipeline.

4. The gas mixing device according to claim 3, characterized in that: The gas distribution plate is a stainless steel wire mesh with a thickness of 1-5 mm, a pore diameter of 1-300 μm, and an opening rate of ≥90%.

5. The gas mixing device according to claim 3, characterized in that: The metal filler is selected from stainless steel triangular spiral filler or Dixon filler, and the size of the filler is 2mm×2mm.

6. The gas mixing device according to claim 3, characterized in that: The volume ratio of the gas mixing unit to the tank body is 0.05-0.

5.

7. The gas mixing device according to claim 3, characterized in that: The nozzle is made of stainless steel, with an aperture of 0.1-0.5 mm, an applicable flow rate of 0-5 L / min, a temperature range of -30-300°C, and a pressure of 0.1-10 MPa.

8. The gas mixing device according to claim 7, characterized in that: The ratio of the number of the nozzles to the flow rate of the hydrogen inlet unit is 0.2-5 / L / min.

9. The gas mixing device according to claim 7, characterized in that: The nozzle is located at 1 / 4-2 / 3 of the gas mixing unit.

10. The gas mixing device according to claim 7, characterized in that: The hydrogen inlet unit and the combustion-supporting gas inlet unit may be arranged at the same position of the tank body, or may be arranged at different positions of the tank body respectively.

11. The gas mixing device according to claim 10, characterized in that: The hydrogen inlet unit is located at the bottom of the tank body, and the combustion-supporting gas inlet unit is located at the side of the tank body at a distance of 0.5-2 cm from the bottom of the tank body.

12. The gas mixing device according to claim 10, characterized in that: The combustion-supporting gas unit is located between the gas mixing unit and the catalyst setting unit, and the volume ratio of the combustion-supporting gas unit to the gas mixing unit is 1.5-4.

13. The gas mixing device according to claim 10, characterized in that: The hydrogen intake unit and the combustion-supporting gas intake unit are arranged at the same position at the bottom of the tank body. The hydrogen intake pipeline of the hydrogen intake unit and the combustion-supporting gas intake pipeline of the combustion-supporting gas intake unit adopt a sleeve form, wherein the hydrogen intake pipeline is a tube side and the combustion-supporting gas intake pipeline is a shell side.

14. Use of the gas mixing device according to any one of claims 1 to 13 in a hydrogen combustion catalytic process.

15. The gas mixing device according to any one of claims 1 to 13, used for mixing hydrogen and air, wherein the volume concentration of hydrogen in the mixed gas of hydrogen and air after mixing by the gas mixing device is 4-29.5%.

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