Pyrolysis gas-assisted thermochemical cycle hydrogen production test system and operation method

Abstract

The invention discloses a pyrolysis gas-assisted thermochemical cycle hydrogen production test system and an operation method. The test system comprises a steam system, a gas path system, a reaction system and a separation detection system. The reaction system adopts a first reaction system and a second reaction system which are arranged in parallel and can alternately carry out reduction and oxidation reactions. And the gas path system can selectively introduce pyrolysis gas or nitrogen into the reaction system through valve switching. According to the operation method, by optimizing water vapor oxidation conditions, an air oxidation stage in a traditional process is omitted, and energy consumption is reduced; and nitrogen purging is adopted during switching of the reaction stages, so that the explosion risk is thoroughly eliminated, and the safety is guaranteed. According to the invention, continuous, efficient and safe circulating hydrogen production is realized, and a reliable scheme is provided for industrial application.

Description

Technical Field

[0001] This invention relates to the field of hydrogen energy production technology, and in particular to a thermochemical cycle hydrogen production experimental system and operating method assisted by pyrolysis gas. Background Technology

[0002] Thermochemical cycle hydrogen production technology assisted by pyrolysis gas is a cutting-edge research direction in the field of hydrogen energy. This technology provides a new approach to achieving efficient and low-carbon hydrogen production by introducing external reducing gases (CO, CH4, H2, etc.). Compared with traditional thermochemical cycle hydrogen production technologies (such as sulfur-iodine cycle, copper-chlorine cycle, etc.), this technology has significant advantages: First, the reducing components contained in the pyrolysis gas can effectively reduce the activation energy of the redox reaction, thereby significantly reducing the reaction temperature; second, this technology reduces carbon emissions and improves economic efficiency by converting carbon elements in organic waste into high-value-added products; in addition, the significant reduction in system operating energy consumption also shows great potential for industrial applications. These technical characteristics make pyrolysis gas-assisted thermochemical cycle hydrogen production uniquely advantageous in addressing the problems of high-temperature heat source requirements, reaction kinetic limitations, and system complexity faced by traditional technologies.

[0003] Existing technologies include patents that propose a combination of biomass gasification and chemical looping hydrogen production. For example, Chinese patent CN202211020669.8 discloses a "biomass gasification-chemical looping hydrogen production device and method," which uses multiple fixed-bed reactors to sequentially perform three reaction steps: oxygen carrier reduction, hydrogen production, and air oxidation, to achieve cyclic hydrogen production. However, this technology has the following technical drawbacks:

[0004] First, the air oxidation step in this scheme is not a necessary process step. Experiments have shown that by optimizing the water vapor oxidation conditions in the hydrogen production process, it is entirely possible to fully oxidize the oxygen carrier to its initial state. Omitting the air oxidation step simplifies the process and reduces energy consumption.

[0005] Secondly, this technical solution does not employ any protective gas purging measures during the switching of each reaction step. This design poses a serious safety hazard in actual operation: when the reactor switches from the reduction step to the hydrogen production step, the residual reducing gases (such as H2, CO, etc.) can easily form an explosive mixture with the introduced water vapor, posing an explosion risk.

[0006] Therefore, there is an urgent need to develop a new scheme for hydrogen production by pyrolysis gas coupling chemical looping that can both ensure process safety and simplify the process. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention aims to solve the problems existing in the prior art by providing a thermochemical cycle hydrogen production experimental system and operating method assisted by pyrolysis gas. On one hand, this invention provides a cycle hydrogen production method comprising only a fuel reduction stage and a steam oxidation stage. By optimizing the reaction conditions of the steam oxidation process and avoiding the use of an air oxidation stage, energy consumption is reduced and hydrogen production efficiency is improved. On the other hand, this invention introduces a nitrogen purging step between the fuel reduction stage and the steam oxidation stage to ensure that the reaction tube is in an inert atmosphere at the beginning of each stage, thereby significantly improving the safety and stability of the system.

[0008] A thermochemical cycle hydrogen production experimental system assisted by pyrolysis gas is characterized by comprising: a steam system, a gas path system, a reaction system, and a separation and detection system; the output ends of the steam system and the gas path system are both connected to the reaction system; the output end of the reaction system is connected to the separation and detection system; the steam system includes an industrial scale, a metering pump, a vaporizer, and a closed-loop high-temperature circulation device, wherein the industrial scale is sequentially connected to the metering pump and the vaporizer, and the closed-loop high-temperature circulation device is connected to the vaporizer; the reaction system includes a first reaction system and a second reaction system with identical structures, both used to contain metal oxides; the separation and detection system includes a first separation and detection system and a second separation and detection system with identical structures; the gas path system includes an external gas source, which is used to provide pyrolysis gas and nitrogen; the gas path system is configured to selectively introduce pyrolysis gas and nitrogen into the first reaction system or the second reaction system.

[0009] Furthermore, the reaction system includes a preheater, a reactor, a heating furnace, and a thermocouple. The output end of the preheater is connected to the reactor, the heating furnace is used to heat the reactor, and the thermocouple is used to monitor and maintain the pipeline temperature.

[0010] Furthermore, the separation and detection system includes a condenser, a gas-liquid separator, a wet gas flow meter, a sampling pump, a drying bottle, and an online gas analyzer. The input end of the condenser is connected to the output end of the reaction system, the output end of the condenser is connected to the gas-liquid separator, the gas output end of the gas-liquid separator is connected to the wet gas flow meter and the sampling pump, the output end of the sampling pump is connected to the drying bottle, and the output end of the drying bottle is connected to the online gas analyzer.

[0011] Furthermore, the steam system is provided with two superheated steam outlets and one safety vent; the gas system is provided with one pyrolysis gas inlet, one nitrogen inlet, two pressure relief ports and two mixed gas outlets.

[0012] Furthermore, the two mixed gas outlets of the gas path system are respectively connected to the air inlets of the preheaters of the first reaction system and the second reaction system via pipelines; the two superheated steam outlets of the steam system are respectively connected to the air inlets of the preheaters of the first reaction system and the second reaction system via pipelines.

[0013] Furthermore, each of the two pyrolysis gas pipelines and the two nitrogen pipelines of the gas system is equipped with a ball valve for controlling the on / off state of the pipelines.

[0014] Furthermore, a three-way ball valve is installed on the pipeline between the metering pump and the vaporizer to control the opening and closing of the water inlet pipe and to drain the water.

[0015] Furthermore, a bellows valve for controlling the on / off state is installed at each of the two superheated steam outlets of the steam system.

[0016] Furthermore, an operating method for a pyrolysis gas-assisted thermochemical cycle hydrogen production experimental system is characterized by comprising the following steps:

[0017] S1: Initial reduction: The oxygen carrier in the second reaction system is reduced with pyrolysis gas at 780-820℃ for 8-10 hours, and then purged with nitrogen.

[0018] S2: Cyclic reaction: Pyrolysis gas is introduced into the first reaction system and undergoes a reduction reaction with the oxidized oxygen carrier at 780-820℃;

[0019] Simultaneously, water vapor is introduced into the second reaction system to produce hydrogen through an oxidation reaction with a reduced oxygen carrier at 780–820°C.

[0020] After 8 to 10 hours of reaction, the first and second reaction systems were purged with nitrogen gas.

[0021] Role switching: By switching valves and controlling flow, the functions of the two reaction systems are interchanged, and step S2 is repeated to achieve continuous hydrogen production.

[0022] Technical effects:

[0023] 1. This invention achieves efficient and continuous hydrogen production by employing two identical parallel reaction systems (first and second reaction systems) and a corresponding separation and detection system. By switching valves in the gas and steam systems, the two reactors can alternately perform reduction and oxidation reactions. While one reactor uses pyrolysis gas to reduce metal oxides (oxygen carrier), the other reactor uses steam to oxidize the reduced metal to produce hydrogen. This design breaks through the limitations of traditional single-reactor batch operation, achieving uninterrupted continuous production and significantly improving system operating efficiency and hydrogen yield.

[0024] 2. Traditional chemical cycle hydrogen production typically involves three stages: fuel reduction, air oxidation, and steam oxidation. The air oxidation stage aims to completely oxidize the incompletely reduced oxygen carrier to restore its lattice oxygen capacity. However, this process is highly exothermic, generating a large amount of useless waste heat, resulting in energy loss, and placing extremely high demands on reactor materials and thermal management. This invention selects an oxygen carrier with excellent cycle performance, characterized by maintaining structural stability even after deep reduction, and completely restoring its lattice oxygen capacity and simultaneously producing high-purity hydrogen through only a steam oxidation stage. Therefore, this invention successfully eliminates the entire "air oxidation" stage.

[0025] 3. This invention employs a mandatory nitrogen purging procedure in its design. Before switching gases at the end of each reaction cycle (8-10 hours), the residual gases in both reaction systems are thoroughly purged with inert nitrogen gas, as explicitly stated in the operating procedures. This design ensures that oxidizing and reducing gases are never present simultaneously in the reactor at any time, fundamentally eliminating the risk of explosion and greatly ensuring the safety of the entire hydrogen production process. This provides a crucial safety foundation for industrial scale-up. Attached Figure Description

[0026] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0027] Figure 1 A schematic diagram of a thermochemical cycle hydrogen production experimental system assisted by pyrolysis gas is shown.

[0028] Figure 2 The diagram shows the gas composition analysis of the two consecutive cycles of water vapor oxidation (SR) stages in an embodiment of the present invention.

[0029] In the diagram: 1-Industrial platform scale, 2-Metering pump, 3-Vaporizer, 4-Nitrogen mass flow controller, 5-Pyrolysis gas mass flow controller, 6-First preheater, 7-Second preheater, 8-First reactor, 9-Second reactor, 10-First condenser, 11-Second condenser, 12-First gas-liquid separator, 13-Second gas-liquid separator, 14-First wet gas flow meter, 15-Second wet gas flow meter, 16-First sampling pump, 17-Second sampling pump, 18-First drying bottle, 19-Second drying bottle, 20-First online gas analyzer, 21-Second online gas analyzer Instrument, 22-Closed-loop high-temperature circulation device, 23-Steam pipeline, 24-Vaporizer inlet pipeline, 25-Vaporizer outlet pipeline, 26-Nitrogen pipeline, 27-Pyrolysis gas pipeline, 28-First reactor inlet pipeline, 29-Second reactor inlet pipeline, 30-First reactor outlet pipeline, 31-Second reactor outlet pipeline, 32-Steam pipeline three-way ball valve, 33-Steam pipeline first bellows valve, 34-Steam pipeline second bellows valve, 35-Nitrogen pipeline second ball valve, 36-Nitrogen pipeline first ball valve, 37-Pyrolysis gas pipeline second ball valve, 38-Pyrolysis gas pipeline first ball valve Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0032] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0033] like Figure 1 As shown, a thermochemical cycle hydrogen production test system assisted by pyrolysis gas is disclosed. The hydrogen production test system includes a steam system, a gas path system, a reaction system, and a separation and detection system.

[0034] The reaction system includes a first reaction system and a second reaction system. The first reaction system and the second reaction system have the same structure. Metal oxides are placed inside the first reaction system and the second reaction system.

[0035] The separation and detection system includes a first separation and detection system and a second separation and detection system, and the first separation and detection system and the second separation and detection system have the same structure.

[0036] The steam system includes a closed-loop high-temperature circulation device 22, an industrial platform scale 1, a metering pump 2, and a vaporizer 3. The closed-loop high-temperature circulation device 22 is used to maintain the temperature of the vaporizer 3. The industrial platform scale 1 is used to weigh the mass of deionized water. The metering pump 2 is used to pump deionized water into the vaporizer. The vaporizer 3 is used to generate superheated steam. The superheated steam is introduced into the reaction system for water flow. The water flow is that the superheated steam reacts with the reduced metal to produce hydrogen and metal oxides.

[0037] The gas path system includes an external gas source and a gas mass flow controller. The external gas source provides the pyrolysis gas and nitrogen required by the reaction system, and the gas mass flow controller controls the flow rate of the pyrolysis gas and nitrogen. The gas path system controls the entry of the pyrolysis gas and nitrogen into the first reaction system or the second reaction system. After the pyrolysis gas enters the reaction system, it undergoes a hot air process, in which the high-temperature pyrolysis gas reacts with the metal oxide to produce reduced metal and a mixed gas. After the nitrogen enters the reaction system, it undergoes a purging process and serves as a carrier gas. The purging process involves the nitrogen blowing away any remaining gases in the reactor, and the carrier gas function involves introducing nitrogen into a reactor that has been introduced with steam to calculate the volume of hydrogen produced. The products of the gas path system and the steam system are alternately introduced into the first reaction system and the second reaction system, respectively, through hot air and water processes.

[0038] The reaction system includes a preheater, thermocouples, a furnace, and a reactor. The preheater is used to preheat the introduced pyrolysis gas and water vapor. The product of the preheater is introduced into the reactor. The thermocouples are used to insulate the high-temperature pyrolysis gas and superheated water vapor in the connecting pipeline. The furnace is used to heat the reactor. The reactor is used to alternately carry out hot air and water flows inside it. The product of the reaction system is introduced into a first separation and detection system and a second separation and detection system for condensation and detection.

[0039] The separation and detection system includes a condenser, a gas-liquid separator, a wet gas flow meter, an online gas analyzer, a sampling pump, and a drying bottle. The condenser is used to cool the incoming high-temperature gas and condense the high-temperature water vapor into liquid water. The gas-liquid separator is used to separate the condensate from the gas. The wet gas flow meter is used to measure the volume of the gas passing through. The sampling pump is used to extract a portion of the gas and pass it into the drying bottle. The drying bottle is used to fill with desiccant to further absorb the moisture in the incoming gas. The online gas analyzer is used to analyze and record the components of each gas after passing through the drying bottle.

[0040] The steam system is equipped with two superheated steam outlets and one safety vent. The gas path system is equipped with one pyrolysis gas inlet, one nitrogen inlet, two pressure relief ports, and two mixed gas outlets. The preheating furnace is equipped with one inlet and one outlet. The reaction tube is equipped with one inlet and one outlet. The condenser is equipped with one inlet, one outlet, one liquid inlet, and one liquid outlet. The gas-liquid separator is equipped with one inlet, one liquid outlet, and two outlets. The sampling pump is equipped with one inlet and one outlet. The drying bottle is equipped with one inlet and one outlet. The online gas analyzer is equipped with one inlet and one outlet. The wet gas flow meter is equipped with one inlet and one outlet. One pyrolysis gas inlet and one nitrogen inlet of the gas path system are connected to an external gas cylinder. The two mixed gas outlets of the gas path system are respectively connected to the inlets of the preheaters of the first reaction system and the second reaction system. The two superheated steam outlets of the steam system are respectively connected to the first reaction system. The gas circuit system is connected to the inlet of the preheater of the second reaction system; the outlet of the preheater is connected to the inlet of the reaction tube; the outlet of the reaction tube is connected to the inlet of the condenser; the outlet of the condenser is connected to the inlet of the gas-liquid separator; the two outlets of the gas-liquid separator are respectively connected to a sampling pump and a wet gas flow meter; the outlet of the sampling pump is connected to the inlet of the drying bottle; the outlet of the dryer is connected to the inlet of the online gas analyzer; and the two pyrolysis gas pipelines of the gas circuit system are connected to the gas circuit system. Each gas system has a ball valve for controlling the on / off state of its corresponding pyrolysis gas pipeline; each of the two nitrogen pipelines in the gas system has a ball valve for controlling the on / off state of its corresponding nitrogen pipeline; a three-way ball valve is installed in the pipeline between the metering pump and the vaporizer for controlling the on / off state and venting of its corresponding water inlet pipeline; and a bellows valve is installed at each of the two superheated steam outlets in the steam system for controlling the on / off state of its corresponding superheated steam outlet.

[0041] An operating method for a thermochemical cycle hydrogen production experimental system assisted by pyrolysis gas is disclosed. The metal oxide used in the experiment is shaped (Ni0.2Co0.2Ca0.2Cu0.2Mg0.2)Fe2O4 particles, which are multi-metal high-entropy oxygen carriers. 8-10 kg of these particles are loaded into each of the two reactors.

[0042] Preparation Stage: Since the oxygen carrier is in an oxidized state after preparation, it needs to be reduced to a reduced state in the second reaction system so that the first and second reaction systems are in different reaction stages. Operating steps: Maintain the temperature of the second preheater 7 at 600–650℃ and the temperature of the second reactor 9 at 780–820℃. Close the first bellows valve 33, the second bellows valve 34, the second ball valve 35, the first ball valve 36, and the first ball valve 38 of the pyrolysis gas pipeline. Open the second ball valve 37 of the pyrolysis gas pipeline. Set the pyrolysis gas mass flow controller 5 to 2–2.5 L / min. Turn on the second sampling pump 17 and set the sampling flow rate to 500–800 ml. The pyrolysis gas is introduced into the second preheater 7 through the pyrolysis gas pipeline 27 and heated to 600–650℃ in the second preheater 7. Then, it passes through the second… The reactor inlet pipe 29 leads into the second reactor 9 to reduce the metal oxide. The generated gas is then condensed in the second condenser 11 via the second reactor outlet pipe 31. The condensed product is then discharged into the second gas-liquid separator 13 to remove the liquid. A small portion of the gas is drawn into the second drying bottle 19 by the second sampling pump 17 and dried. The dried gas is then detected by the second online gas analyzer 21 and then discharged. The remaining gas is discharged after passing through the second wet gas flow meter 15. After 8-10 hours of reaction, the oxygen carrier in the second reactor 9 is basically in a reduced state. Subsequently, the pyrolysis gas mass flow controller 5 is set to 0 L / min, the second ball valve 37 of the pyrolysis gas pipe is closed, the second ball valve 35 of the nitrogen pipe is opened, and the nitrogen mass flow controller 4 is set to 1 L / min. Nitrogen is used to purge the pyrolysis gas from the second reaction system to maintain an inert atmosphere in the second reaction system.

[0043] Cyclic Test 1: Maintain the temperature of the first preheater 6 at 600-650℃, the temperature of the first reactor 8 at 780-820℃, and the temperature of the closed high-temperature circulation device 22 at 200-250℃. Rotate the three-way ball valve 32 of the steam pipeline to the liquid inlet direction, open the second bellows valve 34 of the steam pipeline and the first ball valve 38 of the pyrolysis gas pipeline, set the metering pump 2 to 15-20ml / min, the pyrolysis gas mass flow controller 5 to 2-2.5L / min, open the first sampling pump 16 and the second sampling pump 17, and set the sampling flow rate to 500-800ml. At this time, the pyrolysis gas is introduced into the first preheater 6 through the pyrolysis gas pipeline 27 and heated to 600-650°C in the first preheater 6. Then, it is introduced into the first reactor 8 through the first reactor inlet pipeline 28 to reduce the metal oxide. The generated gas is introduced into the first condenser 10 through the first reactor outlet pipeline 30 for condensation. The condensed product is introduced into the first gas-liquid separator 12 to separate and discharge the liquid. A small portion of the gas is drawn into the first drying bottle 18 by the first sampling pump 16 for drying. The dried gas is introduced into the first online gas analyzer 20 for detection and then discharged. The remaining gas is discharged after passing through the first wet gas flow meter 14. The water flow process involves water being vaporized into steam in vaporizer 3, then flowing through steam pipe 23 into the second preheater 7, where it is heated to 600-650°C. The steam then flows through the second reactor inlet pipe 29 into the second reactor 9, where the metal oxides are oxidized. The resulting gas flows through the second reactor outlet pipe 31 into the second condenser 11 for condensation. The condensed product flows into the second gas-liquid separator 13 to drain the liquid. A small portion of the gas is drawn by the second sampling pump 17 into the second drying bottle 19 for drying. The dried gas is then fed into the second online gas analyzer 21 for detection. Then, the gas is vented. The remaining gas is vented after passing through the second wet gas flow meter 15. After 8 to 10 hours of reaction, the oxygen carrier in the first reactor 8 is basically in a reduced state, and the oxygen carrier in the second reactor is basically in an oxidized state. The metering pump 2 is set to 0 L / min, the pyrolysis gas mass flow controller 5 is set to 0 L / min, the three-way ball valve 32 of the steam pipeline is rotated to vent, the second bellows valve 34 of the steam pipeline and the first ball valve 38 of the pyrolysis gas pipeline are closed, and the first ball valve 36 of the nitrogen pipeline is opened. The residual gas in the entire reaction system is blown out with nitrogen to keep the reaction system inert atmosphere.

[0044] Cyclic Experiment 2: After the reaction system is purged, hydrogen production can be achieved by rotating the three-way ball valve 32 of the steam pipeline, the first bellows valve 33 of the steam pipeline, the second bellows valve 34 of the steam pipeline, the second ball valve 35 of the nitrogen pipeline, the first ball valve 36 of the nitrogen pipeline, the second ball valve 37 of the pyrolysis gas pipeline, and the first ball valve 38 of the pyrolysis gas pipeline, as well as controlling the values ​​of the metering pump 2 and the pyrolysis gas mass flow controller 5.

[0045] like Figure 2 The figure shows the gas composition analysis diagram of the water vapor oxidation (SR) stage in two consecutive cycle experiments in this embodiment of the invention. As can be seen from the figure, the volume of hydrogen produced is 4289L.

[0046] First, by optimizing the conditions of the steam oxidation stage and using a metal oxygen carrier with excellent circulation performance, this invention eliminates the air oxidation stage in the entire process, thereby reducing energy consumption during hydrogen production. Second, by using nitrogen as a purge gas, this invention ensures that oxidizing and reducing gases do not coexist in the reactor, thus reducing safety hazards during hydrogen production. Moreover, this device has achieved continuous circulating hydrogen production with high hydrogen yield and purity, laying the foundation for its industrial application.

[0047] For ease of explanation, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0048] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A pyrolysis gas assisted thermochemical cycle hydrogen production test system, characterized by, It comprises a steam system, a gas path system, a reaction system, and a separation and detection system; the output ends of the steam system and the gas path system are connected with the reaction system; the output end of the reaction system is connected with the separation and detection system; the steam system comprises an industrial platform scale, a metering pump, a vaporizer, and a closed high-temperature circulation device; the industrial platform scale is connected with the metering pump and the vaporizer in sequence; the closed high-temperature circulation device is connected with the vaporizer; the reaction system comprises a first reaction system and a second reaction system which have the same structure and are used for accommodating metal oxides; the separation and detection system comprises a first separation and detection system and a second separation and detection system which have the same structure; the gas path system comprises an external gas source which is used for providing pyrolysis gas and nitrogen; the gas path system is configured to selectively pass the pyrolysis gas and the nitrogen into the first reaction system or the second reaction system. The reaction system comprises a preheater, a reactor, a heating furnace, and a thermocouple; the output end of the preheater is connected with the reactor; the heating furnace is used for heating the reactor; and the thermocouple is used for monitoring and maintaining the pipeline temperature.

2. The pyrolysis gas assisted thermochemical cycle hydrogen production test system according to claim 1, characterized in that: The separation and detection system comprises a condenser, a gas-liquid separator, a wet gas flowmeter, a sampling pump, a drying bottle, and an online gas analyzer; the input end of the condenser is connected with the output end of the reaction system; the output end of the condenser is connected with the gas-liquid separator; the gas output end of the gas-liquid separator is respectively connected with the wet gas flowmeter and the sampling pump; the output end of the sampling pump is connected with the drying bottle; and the output end of the drying bottle is connected with the online gas analyzer.

3. The pyrolysis gas assisted thermochemical cycle hydrogen production test system according to claim 1, characterized in that: The steam system is provided with two superheated steam outlets and one safety vent; and the gas path system is provided with one pyrolysis gas inlet, one nitrogen gas inlet, two pressure relief ports, and two mixed gas outlets.

4. The pyrolysis gas assisted thermochemical cycle hydrogen production test system according to claim 1, characterized in that: The two mixed gas outlets of the gas path system are respectively connected with the gas inlets of the preheaters of the first reaction system and the second reaction system through pipelines; and the two superheated steam outlets of the steam system are respectively connected with the gas inlets of the preheaters of the first reaction system and the second reaction system through pipelines.

5. The pyrolysis gas assisted thermochemical cycle hydrogen production test system according to claim 4, characterized in that: One ball valve for controlling the opening and closing of the pipeline is respectively arranged on each of the two pyrolysis gas pipelines and the two nitrogen gas pipelines of the gas path system.

6. The pyrolysis gas assisted thermochemical cycle hydrogen production test system according to claim 5, characterized in that: A three-way ball valve is arranged on the pipeline between the metering pump and the vaporizer, which is used for controlling the opening and closing of the water inlet pipeline and the emptying.

7. The pyrolysis gas assisted thermochemical cycle hydrogen production test system according to claim 1, characterized in that: A bellows valve for controlling the opening and closing of the pipeline is respectively arranged at each of the two superheated steam outlets of the steam system.

8. The pyrolysis gas assisted thermochemical cycle hydrogen production test system according to claim 4, characterized in that: The method comprises the following steps:

9. A method of operating a test system according to any one of claims 1 to 8, characterised in that, S1: initial reduction: reducing the oxygen carrier in the second reaction system with pyrolysis gas at 780-820℃ for 8-10 hours, and then purging with nitrogen; S2: cyclic reaction: passing pyrolysis gas into the first reaction system to perform a reduction reaction with the oxidized oxygen carrier at 780-820℃; At the same time, passing water vapor into the second reaction system to perform an oxidation reaction with the reduced oxygen carrier at 780-820℃ to produce hydrogen; After 8-10 hours of reaction, purging the first reaction system and the second reaction system with nitrogen; ​ Role switching: by switching the valve and controlling the flow, the functions of the two reaction systems are interchanged, and the continuous hydrogen production is realized by repeating step S2.

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