A method for in-situ catalytic gasification of biomass to produce hydrogen based on a sealed reactor

Abstract

This invention relates to a method for in-situ catalytic gasification of biomass to produce hydrogen based on a sealed reactor. The sealed reactor includes a pipeline system, a gas control system, a U-tube reactor, a lifting and heating system, a detection device, and a water addition device. Specifically, the method involves mixing reactants and catalyst in a specific ratio and then feeding the mixture into the bottom of the U-tube reactor. The U-tube reactor is connected and fixed to the pipeline system. Inert gas is introduced to remove air, and after venting, the valve is closed to keep the U-tube reactor in a sealed state. The U-tube reactor is then heated to carry out the catalytic gasification hydrogen production reaction. In this invention, when biomass undergoes in-situ catalytic gasification hydrogen production inside the U-tube reactor, high-yield and high-selectivity hydrogen production can be achieved simultaneously under relatively mild gasification conditions. The hydrogen selectivity is among the highest in the biomass hydrogen production industry, and the hydrogen yield is also among the highest in the industry, demonstrating significant potential for the industrial application of biomass catalytic gasification hydrogen production.

Description

Technical Field

[0001] This invention belongs to the field of biomass gasification hydrogen production technology, specifically relating to a method for in-situ catalytic gasification hydrogen production from biomass based on a sealed reactor. Background Technology

[0002] Hydrogen energy boasts advantages such as high calorific value and clean, pollution-free operation, making it a crucial component of the modern energy system. Among numerous hydrogen production technologies, biomass catalytic gasification has garnered widespread attention due to its efficient utilization of renewable resources and environmental friendliness. However, improving hydrogen yield and selectivity remains a core challenge for the development of biomass catalytic gasification hydrogen production technology. Simultaneously, reducing energy consumption and equipment complexity are also key considerations for industrial applications.

[0003] Currently, nickel-based catalysts are widely used in biomass catalytic gasification hydrogen production technology due to their excellent dehydrogenation performance and low cost. Meanwhile, the most commonly used devices for biomass catalytic gasification are fixed-bed reactors and fluidized-bed reactors. However, in the available literature on hydrogen production by biomass catalytic gasification based on nickel-based catalysts, the overall performance of fixed-bed reactors and fluidized-bed reactors in terms of hydrogen production efficiency and selectivity is not excellent: (1) In the reports of biomass catalytic gasification experiments using fixed-bed reactors, the highest hydrogen yield can reach 60.0 mmol / g-biomass, but the selectivity is only 62.5 vol.% (Li et al. Fuel, 2023, 334, 126842-126848); (2) In the reports of biomass catalytic gasification hydrogen production experiments using fluidized-bed reactors, the highest hydrogen yield can reach 63.6 mmol / g-biomass, but the selectivity is only 75.0 vol.% (Inayat et al. Int. J. Hydrogen Energ., 2021, 46, 30581-30591). Furthermore, the gasification reaction conditions achieving the highest hydrogen production efficiency in both of the aforementioned reports are quite demanding, requiring a gasification time of 30 minutes and a gasification temperature exceeding 600°C, resulting in relatively high energy consumption for hydrogen production. At a milder gasification temperature, such as 600°C, the hydrogen production rate of the fluidized bed reactor reported by Inayat et al. drops to approximately 20 mmol / g biomass, with selectivity decreasing to approximately 60%. Moreover, comparing this to a device for producing hydrogen via dual fluidized bed biomass pyrolysis gasification disclosed in patent CN201910137452.7, which utilizes a CO2 absorbent circulating within the furnace to carry CO2 from the gasifier to the combustion furnace for release, ultimately yielding syngas with a hydrogen concentration of 49.0%, it can be seen that its hydrogen selectivity is also relatively low, with the product containing a significant amount of byproducts such as CH4, CO, and CO2, hindering subsequent hydrogen purification processes and resulting in higher overall hydrogen production costs.

[0004] The main reasons for the poor performance of fixed-bed and fluidized-bed reactors in the nickel-based catalyst-catalyzed biomass gasification hydrogen production experiment are: (1) the contact time between the pyrolysis gas and the catalyst is relatively short, resulting in low utilization of the active sites of the nickel-based catalyst; (2) the degree of secondary reaction of the biomass gaseous pyrolysis products is low, thus affecting the gasification rate and hydrogen production efficiency. In addition, when using a fluidized-bed reactor for gasification hydrogen production experiments, the catalyst surface will be worn during the collision with biomass particles, resulting in a decrease in catalytic activity, which will also affect the hydrogen production effect of biomass gasification to a certain extent. Therefore, it is crucial to develop a reactor for high-yield and high-selectivity hydrogen production from biomass catalytic gasification. Summary of the Invention

[0005] The purpose of this invention is to provide a method for in-situ catalytic gasification of biomass to produce hydrogen based on a sealed reactor in order to solve the above-mentioned problems.

[0006] The present invention achieves the above objectives through the following technical solutions:

[0007] A method for in-situ catalytic gasification of biomass to produce hydrogen based on a sealed reactor, wherein the sealed reactor includes a pipeline system, a gas control system, a U-tube reactor, a lifting and heating system, a detection device, and a water addition device;

[0008] The specific steps of the biomass in-situ catalytic gasification hydrogen production method are as follows:

[0009] Step 1: Preheat the lifting and lowering heating system to the reaction temperature, mix the reactants and catalyst evenly in proportion, and then send them to the bottom of the U-shaped tube reactor;

[0010] Step 2: Connect and fix the U-tube reactor to the pipeline system, adjust the gas flow using the gas control system, introduce inert gas to remove air, and after exhausting, close the valve to keep the U-tube reactor in a sealed state.

[0011] Step 3: Use the lifting heating system to heat the U-tube reactor for catalytic gasification hydrogen production reaction. The catalytic gasification time is 10 minutes. After completion, allow it to cool naturally for 10 minutes. After cooling, introduce carrier gas, collect the cooled gasified gas and test it.

[0012] As a further optimization of the present invention, the U-shaped tube reactor includes a U-shaped quartz tube and quartz wool, wherein the quartz wool is respectively loaded into both sides of the reactants at the bottom of the U-shaped quartz tube.

[0013] As a further optimization of the present invention, the pipeline system includes a main intake pipe and an exhaust pipe connected to a U-shaped pipe, a first intake pipe, a second intake pipe, a third intake pipe connected to the main intake pipe, and an air collection device connected to the exhaust pipe. The second intake pipe is connected to the first intake pipe and the third intake pipe, and the main intake pipe is connected to the first intake pipe and the second intake pipe.

[0014] As a further optimization of the present invention, the gas control system includes several gas mass flow meters and ball valves II respectively installed on the first inlet pipe, the second inlet pipe, and the third inlet pipe, a needle valve I installed on the main inlet pipe, and a needle valve II installed on the exhaust pipe.

[0015] As a further optimization of the present invention, the lifting heating system includes a lifting mechanism, a heating furnace located at the top of the telescopic end of the lifting mechanism, a temperature controller connected to the heating furnace, a fixing frame for detachably connecting and fixing the U-shaped tube, and a thermocouple extending into the U-shaped tube.

[0016] The water supply device includes an inlet pipe extending into the U-shaped tube and a sample pump connected to the inlet pipe.

[0017] As a further optimization of the present invention, the fixing frame is provided with two through-plate joints, and the two ends of the U-shaped tube are respectively connected and fixed to the lower part of the two through-plate joints by nuts two, and fluororubber ring two is provided in the connection gap. The thermocouple and the water inlet pipe are respectively connected and fixed to the upper part of the two through-plate joints by nuts one, and fluororubber ring one is provided in the connection gap.

[0018] As a further optimization of the present invention, the detection device includes a pressure gauge and a gas detection instrument connected to the gas collection device. The pressure gauge is located between the needle valve and the U-tube, and a ball valve is provided on the input pipe of the pressure gauge.

[0019] As a further optimization of the present invention, in step one, the reaction temperature is in the range of 600-750℃.

[0020] As a further optimization of the present invention, in step two, the U-shaped tube reactor is connected and fixed to the pipeline system, and the water supply device can be turned on to introduce liquid water into the U-shaped tube reactor before venting.

[0021] As a further optimization of the present invention, the mass ratio of reactant to catalyst is 1:3, the reactant is biomass, and the catalyst is Ni / CaO; the biomass is poplar, pine, bamboo, or corn cob.

[0022] The beneficial effects of this invention are as follows:

[0023] 1) In this invention, when biomass undergoes in-situ catalytic gasification to produce hydrogen inside a U-tube reactor, high yield and high selectivity of hydrogen can be achieved simultaneously under relatively mild gasification conditions (i.e., gasification temperature 600℃, gasification time 10min). The hydrogen selectivity can reach the highest level in the biomass hydrogen production industry (93.1 vol.%), and the hydrogen yield is also among the top in the industry (39.6 mmol / g-biomass).

[0024] 2) The sealed catalytic gasification reactor provided by this invention has the advantages of simple structure and low cost, and has great potential for industrial application in biomass catalytic gasification to produce hydrogen. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the sealed reactor in Embodiment 1 of the present invention.

[0026] Figure 2 For the present invention Figure 1 A partial structural diagram.

[0027] Figure 3 This is a comparison chart showing the hydrogen production capacity of different reactants in the sealed reactor of Example 1 using the method of Example 1 for in-situ catalytic gasification hydrogen production.

[0028] Figure 4 This is a comparison diagram showing the hydrogen production effect of in-situ catalytic gasification of poplar wood in a sealed reactor of Example 1 using the method of Example 2.

[0029] Figure 5 This is a comparison chart showing the hydrogen production effect of catalytic gasification hydrogen production reaction of poplar wood in existing common hydrogen production reactors (fixed bed in-situ gasification reactor, two-stage fixed bed non-in-situ gasification reactor, fluidized bed reactor) and the sealed reactor of Example 1 of this application.

[0030] In the diagram: 1. Ball valve one; 2. Gas mass flow meter; 3. Ball valve two; 4. First inlet pipe; 5. Second inlet pipe; 6. Third inlet pipe; 7. Main inlet pipe; 8. T-joint; 9. Two-way connector; 10. Needle valve one; 11. Pressure gauge; 12. Exhaust pipe; 13. Gas collection device; 14. Needle valve two; 15. Fixing frame; 16. Through-plate connector; 17. Thermocouple; 18. U-tube; 19. Heating furnace; 20. Quartz wool; 21. Mixture of catalyst and biomass; 22. Lifting mechanism; 23. Temperature controller; 24. Water inlet pipe; 25. Sample pump; 26. Controller; 27. Nut one; 28. Fluororubber ring one; 29. ​​Fluororubber ring two; 30. Nut two. Detailed Implementation

[0031] The present application will now be described in further detail with reference to the accompanying drawings. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0032] Example 1

[0033] like Figure 1-2 As shown, a sealed reactor includes a piping system, a gas control system, a U-tube reactor, a lifting and heating system, a detection device, and a water addition device.

[0034] The piping system is used for supplying, venting, and collecting gas for the U-tube reactor;

[0035] The gas control system is used to control the gas flow rate of the pipeline system;

[0036] The U-shaped tube reactor is used for in-situ catalytic gasification of reactants and catalysts to produce hydrogen.

[0037] The lifting and heating system is used to heat the U-tube reactor;

[0038] The detection device is used to monitor pressure changes inside the U-tube reactor;

[0039] The water supply device is used to introduce liquid water into the U-shaped tube reactor.

[0040] Preferably, the U-tube reactor includes a U-tube 18 and quartz wool 20. The quartz wool 20 is respectively installed on both sides of the reactant at the bottom of the U-tube to prevent the reactant particles from being carried away by the carrier gas if they are too small or too light. The transparent U-tube 18 is a one-piece design without splicing, and has good airtightness.

[0041] Preferably, the piping system includes a main air inlet pipe 7 and an exhaust pipe 12 connected to a U-shaped pipe 18, a first air inlet pipe 4, a second air inlet pipe 5, and a third air inlet pipe 6 connected to the main air inlet pipe 7, and a gas collecting device 13 connected to the exhaust pipe 12. The second air inlet pipe 5 is connected to the first air inlet pipe 4 and the third air inlet pipe 6, and the main air inlet pipe 7 is connected to the first air inlet pipe 4 and the second air inlet pipe 5, which facilitates the introduction of multiple different carrier gases and allows three different carrier gases to be introduced simultaneously to meet certain specific experimental conditions.

[0042] It should be noted that in this embodiment, the first air intake pipe 4 and the second air intake pipe 5 are both provided with a three-way connector 8 at their output ends, and the third air intake pipe 6 is provided with a two-way connector 9 at its output end, so as to facilitate connection.

[0043] In this embodiment, both the main intake pipe 7 and the exhaust pipe 12 are 3mm stainless steel pipes;

[0044] In this embodiment, the gas collecting device 13 can be either a gas bag or a gas cylinder.

[0045] Preferably, the gas control system includes several gas mass flow meters 2 and ball valves 3 respectively installed on the first intake pipe 4, the second intake pipe 5, and the third intake pipe 6; a needle valve 10 installed on the main intake pipe 7; and a needle valve 14 installed on the exhaust pipe 12. The needle valves here have better sealing effect and can adjust the flow rate. When supplying or exhausting gas, the flow rate starts slowly. The needle valves can prevent the carrier gas flow rate from blowing away the reactants and catalysts in the U-shaped tube 18 due to excessive flow.

[0046] It should be noted that the range of gas mass flow meter 2 is 0-1000 mL / min.

[0047] Preferably, the lifting heating system includes a lifting mechanism 22, a heating furnace 19 located at the top of the telescopic end of the lifting mechanism 22, a temperature controller 23 connected to the heating furnace 19, a fixing frame 15 for detachably connecting and fixing the U-shaped tube 18, and a thermocouple 17 extending into the U-shaped tube 18 to monitor the temperature inside the U-shaped tube 18 in real time.

[0048] The water supply device includes an inlet pipe 24 extending into the U-shaped tube 18 and a sample pump 25 connected to the inlet pipe 24.

[0049] Preferably, the fixing frame 15 is provided with two through-plate connectors 16, and the two ends of the U-shaped tube 18 are respectively connected and fixed to the lower part of the two through-plate connectors 16 by nuts 30, and fluororubber rings 29 are provided in the connection gap. The thermocouple 17 and the water inlet pipe 24 are respectively connected and fixed to the upper part of the two through-plate connectors 16 by nuts 27, and fluororubber rings 28 are provided in the connection gap.

[0050] It should be noted that in this embodiment, the lower diameter of the through-plate connector 16 is 8mm and the upper diameter is 3mm, and the second nut 30 and the first nut 27 correspond to and match the upper and lower parts of the through-plate connector 16.

[0051] In this embodiment, the specifications of the first fluororubber ring 28 are 4mm outer diameter, 2mm inner diameter, and 1mm wire diameter, and the specifications of the second fluororubber ring 29 are 12mm outer diameter, 8mm inner diameter, and 2mm wire diameter.

[0052] The bottom of the thermocouple 17 is 5mm away from the bottom of the U-shaped tube, and the bottom of the water inlet pipe 24 is 1cm away from the bottom of the U-shaped tube.

[0053] Preferably, the detection device includes a pressure gauge 11 and a gas detection instrument connected to the gas collection device 13. The gas detection instrument is used to detect the gas composition inside the gas collection device 13 and perform qualitative and quantitative analysis. The pressure gauge 11 is located between the needle valve 10 and the U-tube 18. A ball valve 1 is provided on the input pipe of the pressure gauge 11. The range of the pressure gauge 11 is 0-0.6 MPa. While closing the needle valve 10 and the needle valve 14, the ball valve 1 at the pressure gauge 11 is also opened. The pressure change inside the U-tube 18 during the catalytic gasification reaction is monitored by the pressure gauge 11. The system pressure range in the closed state is between 0.14-0.20 MPa. In the following Examples 1-2 and Comparative Example 1, the system pressure is 0.14 MPa.

[0054] A method for in-situ catalytic gasification to produce hydrogen based on the above-mentioned sealed reactor, comprising the following specific steps:

[0055] Step 1: Preheat furnace 19 to 600℃, weigh 10mg reactant and 30mg catalyst to make the mass ratio of catalyst to reactant 3:1, and send it into the bottom of U-tube 18. After mixing evenly, stuff a small amount of quartz wool 20 into both sides of the mixture 21 of reactant and catalyst at the bottom of U-tube 18.

[0056] Step 2: Install nut 20 and fluororubber ring 29 sequentially on the upper part of U-tube 18, and then tighten U-tube 18 onto through-plate connector 16 through nut 230. Open ball valve 23, needle valve 10 and needle valve 24, close ball valve 1, control gas mass flow meter 2 to adjust gas flow, blow in several types of gas for exhaust. After exhaust is completed, close needle valve 10 and needle valve 24 at the same time, connect gas collection device 13 to exhaust pipe 12. At this time, U-tube 18 is in a closed state and the system pressure is 0.14MPa.

[0057] Step 3: Raise the heating furnace 19 to heat the U-tube 18 for catalytic gasification hydrogen production reaction. The catalytic gasification time is 10 minutes. After completion, lower the heating furnace 19 to allow the U-tube 18 to cool naturally for 10 minutes. After cooling, first open needle valve 2 14, then open needle valve 10 to introduce carrier gas to prevent excessive gas pressure in the U-tube from rushing into the inlet pipe. Blow the cooled gasified gas into the gas collecting device 13, and send the gas in the gas collecting device 13 to the micro chromatograph (Agilent, MicroGC-990) for detection.

[0058] It should be noted that in this embodiment, the mass ratio of reactant to catalyst is 1:3, the reactant is biomass or plastic, the catalyst is Ni / CaO, the biomass is poplar, pine, bamboo or corn cob, and the plastic is polyethylene.

[0059] Experimental results are as follows Figure 3As shown, when the mass ratio of catalyst to biomass is 3:1, the gasification temperature is 600℃, and the gasification time is 10 min, different types of biomass all exhibit excellent hydrogen production capabilities, with hydrogen yields all exceeding 24.6 mmol / g biomass, and the selectivity for hydrogen in non-condensable gases is around 90 vol.%. Compared to biomass, although the hydrogen yield is increased when polyethylene is used as a raw material (polyethylene has a higher hydrogen content), the hydrogen selectivity is only 62.0 vol.%, resulting in higher costs for secondary purification. Therefore, the sealed reaction system proposed in this invention is more suitable for various biomass catalytic gasification hydrogen production reactions. Biomass gasification products contain a large number of oxygen-containing compounds. Under closed conditions, the thermal motion of oxygen-containing compound molecules is limited to a confined space. Therefore, the yield and selectivity of hydrogen can be improved in the following two ways: First, it increases the number of effective collisions between gaseous molecules, promotes the secondary pyrolysis reaction of the gaseous products themselves, and improves the gasification rate of condensable products. Second, the gaseous pyrolysis product molecules form turbulence in the U-tube 18, which can repeatedly and multiple times contact the catalyst, thereby effectively improving the efficiency of the catalytic gasification reaction. Third, the closed environment (system pressure range of 0.14-0.20 MPa, preferably 0.14 MPa) can promote the adsorption of CO2 by the catalyst, thereby promoting the occurrence of secondary reactions such as water gas and increasing the proportion and purity of hydrogen in the syngas.

[0060] Example 2

[0061] A method for in-situ catalytic gasification to produce hydrogen based on the above-mentioned sealed reactor, comprising the following specific steps:

[0062] Step 1: Preheat the heating furnace 19 to 600℃ or 750℃, weigh 10mg of poplar wood and 30mg of Ni / CaO catalyst, mix them evenly, and send them into the bottom of the U-shaped tube 18. Then, stuff a small amount of quartz wool 20 into both sides of the catalyst and biomass mixture 21 at the bottom of the U-shaped tube 18.

[0063] Step 2: Install nut 20 and fluororubber ring 29 sequentially on the upper part of U-tube 18, and then tighten U-tube 18 onto plate connector 16 with nut 230. Turn on the water filling device to introduce liquid water into U-tube 18, and then open ball valve 23, needle valve 10 and needle valve 24, close ball valve 1, control gas mass flow meter 2 to adjust gas flow, blow in several types of inert gas for exhaust. After exhaust is completed, close needle valve 10 and needle valve 24, and connect gas collecting device 13 to exhaust pipe 12. At this time, U-tube 18 is in a closed state and the system pressure is 0.14MPa.

[0064] Step 3: Raise the heating furnace 19 to heat the U-tube 18 for catalytic gasification hydrogen production reaction. The catalytic gasification time is 10 minutes. After completion, lower the heating furnace 19 to allow the U-tube 18 to cool naturally for 10 minutes. After cooling, first open needle valve 2 14, then open needle valve 10 to introduce carrier gas to prevent excessive gas pressure in the U-tube from rushing into the inlet pipe. Blow the cooled gasified gas into the gas collecting device 13, and send the gas in the gas collecting device 13 to the micro chromatograph (MircoGC-990) for detection.

[0065] Experimental results are as follows Figure 4 As shown, the results indicate that the addition of liquid water improves the hydrogen production efficiency of biomass catalytic gasification. When the mass ratio of catalyst to biomass is 3:1, the gasification temperature is 600℃, the gasification time is 10 min, and the water addition is 20 μL, the hydrogen yield can reach 39.6 mmol / g-biomass, and the selectivity can reach over 93.0 vol.%. When the gasification temperature is increased to 750℃, the hydrogen yield and selectivity are further improved: the hydrogen yield is 47.5 mmol / g-biomass, and the selectivity is higher than 94.0 vol.%. This shows that the sealed reactor of this application can achieve high-yield and high-selectivity hydrogen production through in-situ catalytic gasification of biomass, improving the economic efficiency and environmental friendliness of the reaction.

[0066] Comparative Example 1

[0067] The catalytic gasification of biomass for hydrogen production was carried out using existing fixed-bed and fluidized-bed reactors. The biomass was poplar wood, the catalyst was Ni / CaO, the mass ratio of catalyst to biomass was 3:1, the gasification temperature was 600℃, the system pressure was 0.14MPa, and no liquid water was added.

[0068] Experimental results are as follows Figure 5 As shown, in the case of in-situ catalytic gasification using a two-stage fixed-bed reactor, the hydrogen yield was only 14.7 mmol / g biomass, with a hydrogen selectivity of 44.1 vol.%. In-situ catalytic gasification using a fixed-bed reactor yielded a hydrogen yield of 23.1 mmol / g biomass, with a hydrogen selectivity of 64.6 vol.%. Subsequently, a fluidized-bed reactor was used for biomass catalytic gasification experiments, showing a hydrogen yield of 19.3 mmol / g biomass and a hydrogen selectivity of 67.9 vol.%. It should be noted that both the fixed-bed and fluidized-bed reactors used in the biomass catalytic gasification were hydrogen production reactors disclosed in the literature. When using the sealed reactor of this application for in-situ catalytic gasification of biomass to produce hydrogen, the hydrogen yield at 600°C was 30.2 mmol / g biomass, with a selectivity as high as 91.1 vol.%, indicating that the sealed reactor of this application is superior in its biomass catalytic gasification hydrogen production performance.

[0069] Results Analysis: Figure 5Data shows that commonly used fixed-bed and fluidized-bed reactors both suffer from high CO2 and CO content. However, when using the method in Example 1 of this application for biomass catalytic gasification experiments, the closed environment provided (pyrolysis temperature 600℃, system pressure 0.14MPa) not only allows the pyrolysis gas to repeatedly contact the catalyst, improving the utilization rate of active sites in the catalyst, but also promotes the adsorption of CO2 by the catalyst, thereby effectively promoting the water-gas reaction. and methane reforming reaction This process proceeds in the positive direction, thereby increasing the yield and selectivity of hydrogen.

[0070] Experimental conclusion: Compared with the prior art, the closed reaction system provided in this application, using Ni / CaO as a catalyst for poplar wood, achieves the highest yield and selectivity for hydrogen production.

[0071] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A method for in-situ catalytic gasification of biomass to produce hydrogen based on a sealed reactor, characterized in that: The sealed reactor includes a pipeline system, a gas control system, a U-tube reactor, a lifting and heating system, a detection device, and a water addition device; The specific steps of the biomass in-situ catalytic gasification hydrogen production method are as follows: Step 1: Preheat the lifting and lowering heating system to the reaction temperature, mix the reactants and catalyst evenly in proportion, and then send them to the bottom of the U-shaped tube reactor; Step 2: Connect and fix the U-tube reactor to the pipeline system, adjust the gas flow using the gas control system, introduce inert gas to remove air, and after exhausting, keep the U-tube reactor in a sealed state. Step 3: Use the lifting heating system to heat the U-tube reactor for catalytic gasification hydrogen production reaction. The catalytic gasification time is 10 minutes. After completion, allow it to cool naturally for 10 minutes. After cooling, introduce carrier gas, collect the cooled gasified gas and test it.

2. The method according to claim 1, characterized in that: The U-tube reactor includes a U-tube (18) and quartz wool (20), with the quartz wool (20) being placed on both sides of the reactants at the bottom of the U-tube.

3. The method according to claim 2, characterized in that: The piping system includes a main intake pipe (7) and an exhaust pipe (12) connected to a U-shaped pipe (18), a first intake pipe (4), a second intake pipe (5), a third intake pipe (6) connected to the main intake pipe (7), and an air collection device (13) connected to the exhaust pipe (12). The second intake pipe (5) is connected to the first intake pipe (4) and the third intake pipe (6), and the main intake pipe (7) is connected to the first intake pipe (4) and the second intake pipe (5).

4. The method according to claim 3, characterized in that: The gas control system includes several gas mass flow meters (2) and ball valves (3) respectively installed on the first inlet pipe (4), the second inlet pipe (5), and the third inlet pipe (6), a needle valve (10) installed on the main inlet pipe (7), and a needle valve (14) installed on the exhaust pipe (12).

5. The method according to claim 1, characterized in that: The lifting heating system includes a lifting mechanism (22), a heating furnace (19) located at the top of the telescopic end of the lifting mechanism (22), a temperature controller (23) connected to the heating furnace (19), a fixing frame (15) for detachably connecting and fixing the U-shaped tube (18), and a thermocouple (17) extending into the U-shaped tube (18). The water supply device includes an inlet pipe (24) extending into the U-shaped tube (18) and a sample pump (25) connected to the inlet pipe (24).

6. The method according to claim 5, characterized in that: The fixed frame (15) is provided with two through-plate joints (16). The two ends of the U-shaped tube (18) are respectively connected and fixed to the lower part of the two through-plate joints (16) by nuts two (30) and fluororubber ring two (29) is provided in the connection gap. The thermocouple (17) and the water inlet pipe (24) are respectively connected and fixed to the upper part of the two through-plate joints (16) by nuts one (27) and fluororubber ring one (28) is provided in the connection gap.

7. The method according to claim 1, characterized in that: The detection device includes a pressure gauge (11) and a gas detection instrument connected to the gas collection device (13). The pressure gauge (11) is located between the needle valve (10) and the U-tube (18). A ball valve (1) is provided on the input pipe of the pressure gauge (11).

8. The method according to claim 1, characterized in that: In step one, the reaction temperature is 600-750℃.

9. The method according to claim 1, characterized in that: In step two, the U-tube reactor is connected and fixed to the pipeline system. Liquid water can also be introduced into the U-tube reactor by opening the water supply device, and then the air is vented.

10. The method according to claim 1, characterized in that: The mass ratio of reactant to catalyst is 1:3, the reactant is biomass, and the catalyst is Ni / CaO; the biomass is poplar, pine, bamboo, or corn cob.

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