Methane calcium chain reforming single fluidized bed reaction system and reaction method thereof

Abstract

The invention discloses a methane calcium chain reforming single fluidized bed reaction system and a reaction method thereof. Comprising a columnar quartz tube filled with reaction particles, an adjustable light source located beside the columnar quartz tube, a heat preservation layer wrapping the columnar quartz tube, a position adjusting device used for driving the columnar quartz tube to move and rotate, and thermocouples evenly distributed in the columnar quartz tube, wherein a radiation focus of the adjustable light source is located at the center position of the top of the reaction particles. The gas distribution system is used for supplying reaction gas into the columnar quartz tube, the mass spectrum analyzer is connected with a gas outlet of the columnar quartz tube through a drying tube, the control system is respectively connected with the thermocouple, the gas distribution system and the mass spectrum analyzer, and an incident port is formed in one side surface, facing the adjustable light source, of the thermal insulation layer. The invention aims to realize efficient absorption and conversion of energy on the basis of reducing heat dissipation, and hydrocarbon fuel with high added value is obtained while CO2 is captured.

Description

Technical Field

[0001] The present invention relates to the technical field of fluidized bed reaction, and particularly to a single fluidized bed reaction system for methane calcium chain reforming and a reaction method thereof. Background Art

[0002] Photothermal methane calcium chain reforming combines solar-driven calcium looping thermochemical energy storage technology with methane dry reforming. It can use solar energy to drive calcium looping to capture CO 2 and realize CH 4 dry reforming, reasonably utilize renewable energy while reducing carbon emissions, and alleviate the carbon deposition problem during the reaction process.

[0003] However, most of the existing technical routes for calcium chain methane dry reforming place the methane dry reforming reaction and the reverse reaction of the carbonation reaction of CaO in two different fluidized bed reactors, and connect the two with pipelines. The calcium-based heat transfer medium moves and stays in different regions to carry out corresponding reactions. Frequent particle flow will result in high heat loss, and two independent fluidized bed reactors require two light sources or other forms of heat sources to drive the reaction. Therefore, there are extremely high requirements for system design aspects such as pipeline layout, heat source matching, and heat insulation performance. Moreover, due to the particularity of unilateral solar irradiation, the light source it provides can often only converge at a single focus. Therefore, the dual-fluidized bed scheme requires one solar-heated fluidized bed and one electrically heated fluidized bed each, and the electrical heating method deviates from the original intention of realizing the utilization of clean energy.

[0004] Therefore, it is urgent to solve the above problems. Summary of the Invention

[0005] Object of the Invention: The first object of the present invention is to provide a single fluidized bed reaction system for methane calcium chain reforming, aiming to achieve efficient absorption and conversion of energy on the basis of reducing heat dissipation, capture CO 2 while obtaining high-value hydrocarbon fuels.

[0006] The second object of the present invention is to provide a reaction method for the single fluidized bed reaction system for methane calcium chain reforming.

[0007] Technical solution: To achieve the above object, the present invention discloses a methane calcium chain reforming single-fluidized bed reaction system, which includes a columnar quartz tube filled with reaction particles, a controllable light source located beside the columnar quartz tube and with the radiation focus at the top center position of the reaction particles, a heat insulation layer wrapped outside the columnar quartz tube, a position adjusting device for driving the movement of the columnar quartz tube, thermocouples evenly distributed in the columnar quartz tube, a gas distribution system for supplying reaction gases into the columnar quartz tube, a mass spectrometer connected to the outlet of the columnar quartz tube through a drying tube, and a control system respectively connected to the thermocouples, the gas distribution system and the mass spectrometer, wherein an incident port is provided on one side of the heat insulation layer facing the controllable light source.

[0008] Optionally, the shape of the incident port is formed by the overlap of several cones with the center lines in the same plane. The initial center line of the cone is perpendicular to the plane where the opening side is located, the vertex of the cone is on the central axis of the columnar quartz tube, and the cone is rotated clockwise by a certain angle. The overlapping part of the cut cone and the heat insulation layer is the incident port.

[0009] Optionally, the gas distribution system includes an argon gas cylinder, a carbon dioxide gas cylinder and a methane gas cylinder all equipped with flow meters, wherein the argon gas cylinder, the carbon dioxide gas cylinder and the methane gas cylinder are respectively connected to the inlet of the columnar quartz tube through pipes with heating tapes, and the heating tapes are connected to the control system.

[0010] Optionally, the reaction particles are Ca-Ni-based composite particles.

[0011] Optionally, the stacking height of the reaction particles exceeds the lower end of the incident port of the heat insulation layer by 3 to 5 mm.

[0012] Optionally, the power of the controllable light source is adjustable, and the rated power is 1000 w.

[0013] Optionally, the controllable light source is placed on a positioning platform. A pair of support rods are connected between the front side of the positioning platform and the ground, and a pair of electric push rods for changing the irradiation angle of the light source are connected between the rear side of the positioning platform and the ground.

[0014] Optionally, the position adjusting device includes a horizontal sliding table, a vertical sliding table connected to the slider of the horizontal sliding table, and an angular tilting sliding table connected to the slider of the vertical sliding table. The working surface of the angular tilting sliding table is connected to the columnar quartz tube, and the base of the angular tilting sliding table is connected to the slider of the vertical sliding table.

[0015] Optionally, an exhaust pipe is also connected to the drying tube.

[0016] Based on the same technical concept, the present invention discloses a reaction method of a methane calcium chain reforming single-fluidized bed reaction system, which includes the following steps: By adjusting the position adjustment device and the inclination angle of the adjustable light source, the radiation focus of the adjustable light source is located at the top center position of the reaction particles; by rotating the angle tilt stage, the inclination angle of the columnar quartz tube can be adjusted, so that the heat transfer working medium inside the quartz tube moves to the radiation irradiation surface under the action of gravity. Turn on the heating tape, control the gas distribution system to introduce Ar at 3000 - 5000 mL / min. It can be observed from the incident port of the heat preservation layer that the reaction particles in the columnar quartz tube remain stationary; turn on the adjustable light source and set its power to 800 - 1000 w. The gas inside the columnar quartz tube expands due to heat, and the particles start to move and enter the fluidization stage in advance. Control the gas distribution system to introduce 2400 mL / min of Ar and 600 mL / min of CO 2 , the thermocouple measures the internal temperature of the columnar quartz tube and transmits it to the control system. The reaction particles in the columnar quartz tube continue to fluidize. When the temperature rises to 600 °C - 650 °C, control the reaction to enter the CH 4 dry reforming stage; Control the gas distribution system to introduce 2400 mL / min of Ar and 600 mL / min of CH 4 , the decomposition reaction of CaCO 3 and the CH 4 dry reforming reaction occur inside the columnar quartz tube; CaCO 3 in the reaction particles decomposes into CaO and CO 2 , and CO 2 reacts with CH 4 to occur the dry reforming reaction; when the mass spectrometer monitors that the volume flow rate of CO 2 in the tail gas is less than 2%, control the reaction to enter the CaO carbonation stage; Adjust the power of the adjustable light source to 600 - 700 w, control the gas distribution system to introduce 2400 mL / min of Ar and 600 mL / min of CO 2 , the removal of coke and the carbonation of CaO occur; when the mass spectrometer monitors that the volume flow rate of CO 2 in the tail gas reaches 18 - 22%, the conversion of CaO to CaCO 3 is completed.

[0017] Beneficial effects: Compared with the prior art, the present invention has the following remarkable advantages: (1) The present invention uses a laboratory-scale adjustable light source to provide radiant energy for the reaction system, realizes the conversion of photothermal energy, avoids the carbon emission problem brought by traditional energy input, has a guiding role for large-scale solar energy utilization, and can realize the collaborative utilization and energy storage of solar energy and chemical energy.

[0018] (2) The present invention realizes that the fluidized bed reaction system fully receives and utilizes the radiant heat of the light source by means of improving the heat insulation layer and adjusting the relative position of the space; specifically, the inclination angle of the light source can be flexibly adjusted, the fluidized bed system is provided with a heat insulation layer, and the heat insulation layer is provided with an opening to receive the radiation, and the shape of the opening matches the radiation characteristics; the vertical and horizontal positions of the fluidized bed can be adjusted extremely conveniently, and the inclination angle of the fluidized bed can be adjusted, so that the working medium inside the fluidized bed moves under the action of gravity to the radiation irradiation area, realizing a high photothermal conversion efficiency; the most suitable spatial distribution of the light source-reactor can be obtained by comprehensively adjusting the angle of the light source. In addition, the power of the light source can also be adjusted in a timely manner according to the reaction conditions to avoid problems such as uneven temperature field inside the reactor and particle corrosion of the wall surface.

[0019] (3) The present invention adopts a single fluidized bed, integrating all the reactions involved in the unique fluidized bed reactor, greatly simplifying the design. Only a single heat source is required to supply heat to the entire system, which conforms to the characteristics of relatively concentrated solar radiation distribution; compared with the traditional dual-fluidized bed structure that separates dry reforming and carbonation, the single-fluidized bed scheme can avoid the movement of particles inside different reactors and utilize the heat generated in the previous step, thereby reducing heat loss and having a higher energy storage efficiency.

[0020] (4) The present invention uses Ca-Ni-based composite solid particles as the reaction medium, which has both high energy storage density and high catalytic efficiency; doping with other metal elements is beneficial to improving the spectral absorption capacity, anti-sintering performance and cycle stability of the particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of the system of the present invention; Figure 2 is a schematic diagram of the shape of the heat insulation layer in the present invention; Figure 3 is a schematic diagram of the formation of the incident port of the heat insulation layer in the present invention; Figure 4 is a schematic diagram of the particle movement inside the columnar quartz tube in the present invention; Figure 5 is a graph showing the change of the volume flow rate of each gas component with time in the present invention; Figure 6 is a graph showing the change of the temperature inside the columnar quartz tube with time in the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] The technical solutions of the present invention will be further described below with reference to the accompanying drawings.

[0023] As Figure 1As shown in the figure, a methane calcium chain reforming single-fluidized bed reaction system of the present invention includes a columnar quartz tube 1, a controllable light source 2, a thermal insulation layer 3, a position adjusting device 4, a thermocouple 5, a gas distribution system 6, a drying tube 7, a mass spectrometer 8, a control system 9, a flowmeter 10, a positioning platform 11, a support rod 12, an electric push rod 13, an exhaust pipe 14 and a data acquisition system 15.

[0024] The columnar quartz tube 1 is filled with reaction particles, and the stacking height of the reaction particles exceeds the lower end of the incident port of the thermal insulation layer by 3 to 5 mm to ensure that the particles can fully receive the radiant heat released by the controllable light source 2 and react; the reaction particles are Ca-Ni-based composite particles, and the Ca-Ni-based composite particles are bifunctional particles integrating high-efficiency energy storage and catalysis, that is, while having a high energy storage density and catalytic characteristics, they also have a high spectral absorption rate and cycle stability; specifically, the CaCO 3 / CaO component in the Ca-Ni-based composite particles realizes thermochemical energy storage, absorbs and converts the radiant heat released by the controllable light source 2, and the Ni element can be used to catalyze the dry reforming reaction of methane. Dark metal elements and stabilizers are appropriately doped in the particles to improve the spectral absorption rate and cycle stability of the reaction materials. Using Ca-Ni-based composite particles as the reaction medium of the methane calcium chain reforming system, Ce and Al elements are also doped in the preparation process, which have excellent energy storage characteristics, catalytic activity, spectral absorbance and cycle stability. The present invention uses the extrusion and spheronization method to prepare particles, and the ratio of Ca-Al-Ce-Ni is 100-10-4-12. All reactions occur inside the columnar quartz tube 1 during the entire photothermal energy storage process of the present invention, that is, the calcium cycle, the dry reforming reaction of methane and the reverse Boudouard reaction occur inside the columnar quartz tube 1. The selected columnar quartz tube 1 has an inner diameter of 26 mm, an outer diameter of 30 mm, and a tube length of 210 mm, and a gas distribution plate is installed 70 mm from the bottom of the quartz tube. A gas distribution plate is arranged inside the columnar quartz tube 1 to carry the reaction particles and make the inlet gas evenly distributed; Ca-Ni-based composite particles are stacked above the gas distribution plate, having excellent energy storage-catalysis effects. An inlet is arranged at the bottom of the columnar quartz tube 1, and an outlet is arranged at the top of the columnar quartz tube 1. The calcium cycle and the dry reforming reaction of methane can occur inside the columnar quartz tube 1. With the data obtained by the control system as a reference, the gas distribution system 6 is controlled to adjust the inlet gas, so as to occur the expected reaction inside the columnar quartz tube 1; first, CH 4 is introduced into the columnar quartz tube 1, and CaCO 3 decomposes and stores radiant heat, and the generated CO 2 reacts with CH 4 to occur the dry reforming reaction; when CaCO 3 is exhausted, that is, after the reforming reaction is complete, CO 2 is introduced, and CaO is recarbonated to generate CaCO 3, which can be used for the next cycle. The columnar quartz tube 1 receives radiation and undergoes all relevant reactions, with the internal temperature reaching up to 800 °C during the process, ensuring that the reaction can proceed efficiently and stably.

[0025] The adjustable light source 2 is located beside the columnar quartz tube. The adjustable light source 2 realizes unilateral irradiation in the form of simulated thermal radiation to provide heat for the chemical reaction; the radiation focus of the adjustable light source 2 is located at the top center position of the reaction particles, which can prevent particle sintering or reaction with the components of the quartz tube to corrode the wall surface; the power of the adjustable light source 2 is adjustable, with a rated power of 1000 w. The internal program can be set so that the power switches from 1000 w to 600 w every 15 minutes, and then switches from 600 w to 1000 w after 15 minutes, for a total of three cycles. As a radiation heat source, the adjustable light source 2 can provide heat and the required high-temperature environment for the calcium cycle and the dry reforming of methane reaction, and introducing light can reduce the activation energy of the reaction and promote the reaction to proceed at 600 °C - 700 °C. The adjustable light source 2 is placed on the positioning platform 11, and a pair of support rods 12 are connected between the front side of the positioning platform 11 and the ground, and a pair of electric push rods 13 are connected between the rear side of the positioning platform and the ground. The support rod 12 can be a support rod with a fixed length or a support rod with an adjustable length; the length of the electric push rod 13 is adjustable. By adjusting the length of the electric push rod 13, the inclination angle of the positioning platform is adjusted, and the horizontal inclination angle of the adjustable light source 2 is changed. At the same time, the position adjustment device 4 can drive the columnar quartz tube 1 to move. The position adjustment device 4 includes a horizontal slide table 4, a vertical slide table connected to the slider of the horizontal slide table, and an angular tilt slide table connected to the slider of the vertical slide table. Among them, the working surface of the angular tilt slide table 17 is connected to the columnar quartz tube, and the base of the angular tilt slide table 17 is connected to the slider of the vertical slide table. The angular tilt slide table 17 can control the vertical inclination angle of the columnar quartz tube 1 to be adjusted between 0° and 20°. Such as Figure 4As shown, the columnar quartz tube 1 is rotated counterclockwise by a certain angle, and the internal particles are fluidized and rise by the gas from the inlet, and then move to the radiation irradiation surface under the action of gravity. By adjusting the position of the columnar quartz tube 2, the relative position between the adjustable light source 2 and the columnar quartz tube 1 is changed to ensure that the radiation focus of the adjustable light source 2 is located at the top center position of the reaction particles. The most suitable distance between the adjustable light source 2 and the columnar quartz tube 1 is 12 to 15 cm, and the horizontal tilt angle of the adjustable light source 2 is 20°, which can effectively alleviate the problems of light attenuation and reactor corrosion and significantly improve the radiation uniformity. The adjustable light source 2 can flexibly adjust the irradiation angle, the relative distance from the columnar quartz tube 1, and the operating power to adapt to different reaction conditions inside the fluidized bed reactor. The position of the adjustable light source 2 on the positioning platform 11 can change its relative distance from the columnar quartz tube 1, and controlling the stretching length of the electric push rod 13 on the positioning platform 11 can change the radiation irradiation angle of the adjustable light source 2; changing the power of the adjustable light source 2 at different stages can further control the temperature inside the reaction system by changing the light intensity. During the dry reforming process, the power of the adjustable light source 2 is changed to control the temperature inside the columnar quartz tube 1 to reach 800 °C. During the CaO carbonation process, the power of the adjustable light source 2 is changed to control the temperature inside the columnar quartz tube 1 to be reduced to 600 °C.

[0026] As Figure 3 and Figure 5 shown, the heat insulation layer 3 is wrapped outside the columnar quartz tube. An incident port 301 is provided on the side of the heat insulation layer 3 facing the adjustable light source to receive the simulated radiant heat; the simulated solar radiation can be regarded as a conical shape, and the volume of the cone depends on the parameters of the inner lamp shade of the adjustable light source 2, and the heat insulation layer is correspondingly cut according to its characteristics. To make the reaction proceed efficiently, the opening diameter of the lamp shade is selected to be 150 to 170 mm, and the focal length is 140 to 170 mm. The shape of the incident port of the heat insulation layer is formed by the overlap of several cones whose center lines are in the same plane. The initial center line of the cone is perpendicular to the plane where the opening side is located, and the vertex of the cone is located on the central axis of the columnar quartz tube 1. The cone is rotated clockwise by 40°, and the overlapping part of the cut cone and the heat insulation layer is the required incident port of the heat insulation layer, which is conducive to fully receiving the radiant heat released by the adjustable light source 2; the spatial distribution can be regarded as the radiant heat of the cone entering the columnar quartz tube through the incident port. The radiation generated by the used light source lamp shade can be regarded as a conical shape with a bottom side length of 162 mm and a height of 15 mm, and the opening of the heat insulation layer is correspondingly cut according to its characteristics. The main raw material of the heat insulation layer 3 is aluminosilicate, and its shape and its layout with the columnar quartz tube 1 are as Figure 3 shown. While ensuring the airtightness of the overall columnar quartz tube, the exposed quartz tubes above and below the heat insulation layer 3 are wrapped with heat insulation materials such as quartz wool to alleviate the problem of heat dissipation during the operation of the system.

[0027] The thermocouples 5 are evenly distributed in the columnar quartz tube 1, and the thermocouples 5 are connected to the control system. The thermocouples are distributed along the central axis of the columnar quartz tube at an interval of 2 cm, which can monitor the temperature changes of the particles at different heights in the columnar quartz tube in real time, providing accurate thermal distribution data support for the research. The thermocouples 5 monitor the internal temperature of the columnar quartz tube 1 in real time, and the data is transmitted to the control system, providing a reference for the regulation of the gas distribution system 6.

[0028] The gas distribution system 6 supplies Ar, CO 2 and CH 4 into the columnar quartz tube. The gas distribution system 6 includes an argon gas cylinder, a carbon dioxide gas cylinder, and a methane gas cylinder, all of which are equipped with flow meters 10. Among them, the argon gas cylinder, the carbon dioxide gas cylinder, and the methane gas cylinder are respectively connected to the inlet of the columnar quartz tube 1 through pipes with heating tapes 15. The gas distribution system 6 is connected to the control system, and the heating tape 15 is connected to the control system through the data acquisition system 16. The control system reads the temperatures of the gas and particles at different positions in the columnar quartz tube 1 to evaluate the heat transfer performance and reaction efficiency. The gas distribution system 6 regulates the composition and flow rate of the gas during the reaction. The gas is preheated by the heating tape 15 before entering the columnar quartz tube 1 to improve the reaction efficiency. To improve the overall reaction rate, a heating tape 15 is installed on the gas transport channel before entering the columnar quartz tube, so that the gas enters the columnar quartz tube at a higher temperature and participates in the reaction. The gas flow rate is regulated by the flow meter 10. By changing the reaction parameters such as the gas flow rate and radiation amount, the specific reaction inside the columnar quartz tube is determined. The control system can regulate the gas distribution system 6 to change the composition and ratio of the gas distribution, and control the internal reaction of the columnar quartz tube to switch between methane dry reforming and calcium oxide carbonation.

[0029] The mass spectrometer 8 is connected to the outlet of the columnar quartz tube through the drying tube 7. The drying tube 7 is also connected to an exhaust pipe 14. The mass spectrometer 8 is connected to the control system 9. The inside of the drying tube 7 is filled with discolored silica gel. The gas discharged from the columnar quartz tube first passes through the drying tube 7 to avoid the interference of moisture and fine dust on the subsequent treatment. A part of the dried gas is discharged from the exhaust pipe 14, and the remaining dried gas enters the mass spectrometer 8. The data collected by the mass spectrometer 8 is entered into the control system. The mass spectrometer 8 can show the composition and changes of the gas at different times. By connecting the mass spectrometer 8 to the control system, the control system 6 can obtain a real-time gas content change image, which has a guiding role in the analysis of the reaction mechanism and can cooperate with the control system to achieve more reasonable and timely regulation of the reaction. Specifically, when the volume fraction of CO 2 monitored by the control system is 0 and the internal temperature of the monitored system is the highest, the methane dry reforming reaction is basically over. At this time, the control system can be entered into the calcium oxide carbonation reaction; CO 2When the volume fraction reaches a stable peak and the internal temperature of the system is the lowest, the carbonation reaction of calcium oxide is basically completed. At this time, the control system can re-enter the methane dry reforming reaction.

[0030] The columnar reaction tube involved in the present invention adopts a fluidized bed form, with sufficient contact between the internal fluid and the reaction medium, having small heat loss, high heat transfer and mass transfer efficiency, and a more uniform temperature distribution; at the same time, the fluidized bed reaction system has strong operability, and it can operate in a continuous processing state and continuously introduce new gases, eliminating the start-up conditions in the batch process and improving the overall efficiency; specifically, the reaction gas provided by the gas distribution system can be switched between CH4 and CO2, and the two gases participate in the CH4 dry reforming and CaO carbonation processes respectively; when switching gases, there is no need to restart the reaction system, and the particles are in a fluidized state at all times during the complete reaction process, greatly improving the reaction efficiency and reducing the time cost.

[0031] The reaction system involved in the present invention integrates solar radiation absorption, CO2 capture and fuel conversion, realizing the in-situ conversion and utilization of solar energy and CO2; providing heat for the system in the form of thermal radiation, the calcium cycle energy storage and methane dry reforming processes occur in the same fluidized bed reactor, and the characteristics of the fluidized bed being easy to operate are used to timely adjust reaction parameters such as gas flow rate and incident radiation, and flexibly adjust the reactions occurring inside the bed according to requirements; due to the characteristics of calcium cycle heat storage, multiple cycles can be experienced in the fluidized bed, and at the same time, the Ca-Ni-based composite material has a high energy storage density and high catalytic efficiency, and the whole system has a high energy storage efficiency and stability.

[0032] A reaction method for a single-fluidized bed reaction system of methane calcium chain reforming according to the present invention includes the following steps: By adjusting the position adjusting device and the inclination angle of the adjustable light source, the radiation focus of the adjustable light source is located at the top center position of the reaction particles, and the fluidized bed is rotated counterclockwise by 5° to 10°, so that the particles inside the fluidized bed receive more radiant heat under the action of gravity without sintering. Turn on the heating belt, set its temperature to 270 °C, control the gas distribution system to introduce 4700 mL / min of Ar, and it can be observed from the incident port of the heat preservation layer that the reaction particles in the columnar quartz tube remain stationary; turn on the adjustable light source and set its power to 1000 w, the gas inside the columnar quartz tube expands due to heat, and the particles start to move violently at a high speed, that is, the particles enter the fluidization process; enabling the particles to enter the fluidization stage earlier and matching the radiation characteristics, enabling the subsequent reactions to proceed more stably and efficiently; the premature fluidization of the particles can also alleviate the sintering problem caused by continuous irradiation of the stationary particles by radiation. Control the gas distribution system to introduce 2400 mL / min of Ar and 600 mL / min of CO 2 containing CO2 The gas can avoid the CaCO in the Ca-Ni based composite material 3 The components undergo decomposition reaction in advance; the thermocouple measures the temperature inside the columnar quartz tube and transmits it to the control system. The reaction particles in the columnar quartz tube continue to fluidize and heat up to 600°C at a high rate, then the heating rate slows down and the temperature tends to stabilize; that is, when the temperature rises to 600°C to 650°C, the reaction is controlled to enter CH 4 Dry reforming stage; The gas distribution system was controlled to introduce 2400 mL / min of Ar and 600 mL / min of CH 4 , CaCO occurs in the columnar quartz tube 3 Decomposition reaction and CH 4 Dry reforming reaction, the chemical formula of the reaction is the forward process of formula (1) and formula (2); CaCO in the reaction particles 3 Decomposes into CaO and CO 2 , CO 2 With CH 4 Dry reforming reaction occurs; this process is catalyzed by the metal Ni in the composite material, CO 2 As a reaction gas, CH 4 The dry reforming process can also reduce CO 2 partial pressure, thereby accelerating CaCO 3 The decomposition reaction of CH 4 Dry reforming obtains sufficient reaction gas; the temperature inside the reactor measured by the thermocouple is as high as 800°C. 4 After 15 minutes of dry reforming, the CaCO 3 The reaction is complete, the temperature inside the columnar quartz tube tends to be stable, and the mass spectrometer monitors the CO in the system exhaust. 2 The flow rate is almost 0, that is, when the mass spectrometer detects CO in the exhaust gas 2 When the volume flow rate is less than 2%, the reaction is controlled to enter the CaO carbonation stage; (1) (2) (3) Adjust the power of the adjustable light source to 600w, and control the gas distribution system to introduce 2400mL / min of Ar and 600mL / min of CO 2 , coke removal and CaO carbonation occur, which is the reverse process of equations (3) and (1); a small amount of CO can be monitored in the mass spectrometer at the beginning of the stage, that is, coke and CO 2 The CaO generated in the dry reforming stage is converted back into CaCO in the carbonation stage. 3, can be used for the next dry reforming reaction; the lowest temperature in this stage is lower than 500 °C, but it can achieve the carbonation of CaO at a relatively high rate, and the conversion of CaO to CaCO 3 is completed after 15 minutes; that is, when the volume flow rate of CO 2 in the tail gas monitored by the mass spectrometer reaches 18-22%, the conversion of CaO to CaCO 3 is completed.

[0033] By controlling the different components and flow rates of the gas distribution and the power switching of the adjustable light source, different reactions occur in the control system, and the interval between each adjustment is 15 minutes. One dry reforming stage and one carbonation stage are called a cycle, and the gas supply is stopped after three cycles. The entire reaction system realizes the synergistic utilization and energy storage of solar energy and chemical energy, integrating solar radiation absorption, CO 2 capture and fuel conversion, achieving the in-situ conversion and utilization of solar energy and CO 2 Moreover, the reaction medium can be recycled, which can give full play to the advantages of the Ca-Ni-based composite material and maximize the development of its energy storage performance. All reactions occur inside the columnar quartz tube, greatly simplifying the design, facilitating operation and adjustment, avoiding unnecessary medium transportation, reducing heat dissipation and improving energy conversion efficiency.

Claims

1. A methane calcium chain reforming single fluidized bed reaction system, characterized in that: The invention comprises a columnar quartz tube filled with reaction particles, an adjustable light source located beside the columnar quartz tube and having a radiation focus located at the top center of the reaction particles, a heat preservation layer wrapped around the outside of the columnar quartz tube, a position adjustment device for driving the columnar quartz tube to move and rotate, thermocouples evenly distributed in the columnar quartz tube, a gas distribution system for supplying reaction gas into the columnar quartz tube, a mass spectrometer connected to the gas outlet of the columnar quartz tube through a drying tube, and a control system respectively connected to the thermocouple, the gas distribution system and the mass spectrometer, wherein an incident port is provided on a side of the heat preservation layer facing the adjustable light source, the incident port is formed by overlapping a plurality of cones whose center lines are located in the same plane, the initial center line of the cone is perpendicular to the plane where the opening side is located, the apex of the cone is located on the central axis of the columnar quartz tube, the cone is rotated clockwise by a certain angle, and the overlapping part of the cone and the heat preservation layer is cut to obtain the incident port.

2. The methane calcium chain reforming single fluidized bed reaction system according to claim 1, characterized in that: The gas distribution system comprises an argon gas cylinder, a carbon dioxide gas cylinder and a methane gas cylinder, all of which are equipped with flow meters, wherein the argon gas cylinder, the carbon dioxide gas cylinder and the methane gas cylinder are respectively connected to the gas inlet of the columnar quartz tube through a pipeline with a heating belt, and the heating belt is connected to a control system.

3. The methane calcium chain reforming single fluidized bed reaction system according to claim 1, characterized in that: The reaction particles are Ca-Ni based composite particles.

4. The methane calcium chain reforming single fluidized bed reaction system according to claim 1, characterized in that: The stacking height of the reaction particles exceeds the lower end of the incident port of the insulation layer by 3 to 5 mm.

5. The methane calcium chain reforming single fluidized bed reaction system according to claim 1, characterized in that: The power of the adjustable light source is adjustable, and the rated power is 1000w.

6. The methane calcium chain reforming single fluidized bed reaction system according to claim 1, characterized in that: The adjustable light source is placed on a positioning platform, a pair of support rods are connected between the front side of the positioning platform and the ground, and a pair of electric push rods that can change the irradiation angle of the light source are connected between the rear side of the positioning platform and the ground.

7. The methane calcium chain reforming single fluidized bed reaction system according to claim 1, characterized in that: The position adjustment device includes a horizontal slide, a vertical slide connected to the slider of the horizontal slide, and an angle-tilted slide connected to the slider of the vertical slide, wherein the working surface of the angle-tilted slide is connected to the columnar quartz tube, and the base of the angle-tilted slide is connected to the slider of the vertical slide.

8. The methane calcium chain reforming single fluidized bed reaction system according to claim 1, characterized in that: The drying pipe is also connected with an exhaust pipe.

9. A reaction method of a single fluidized bed reaction system for methane calcium chain reforming according to any one of claims 1 to 8, characterized in that: The steps include: By adjusting the position adjustment device and the inclination angle of the adjustable light source, the radiation focus of the adjustable light source is located at the top center of the reaction particle; by rotating the angle tilting slide, the inclination angle of the columnar quartz tube can be adjusted, so that the heat transfer medium inside the quartz tube moves to the radiation irradiation surface under the action of gravity; Turn on the heating belt, control the gas distribution system to introduce 3000-5000mL / min of Ar, and observe from the entrance of the insulation layer that the reaction particles in the columnar quartz tube remain stationary; turn on the adjustable light source and set its power to 800-1000w, the gas inside the columnar quartz tube expands due to heat, and the particles begin to move and enter the fluidization stage in advance; The gas distribution system is controlled to introduce 2400mL / min of Ar and 600mL / min of CO2. The temperature inside the columnar quartz tube is measured by a thermocouple and transmitted to the control system. The reaction particles in the columnar quartz tube are continuously fluidized. When the temperature rises to 600℃~650℃, the reaction is controlled to enter the CH4 dry reforming stage. The gas distribution system is controlled to introduce 2400 mL / min of Ar and 600 mL / min of CH4, and a CaCO3 decomposition reaction and a CH4 dry reforming reaction occur in the columnar quartz tube; the CaCO3 in the reaction particles is decomposed into CaO and CO2, and a dry reforming reaction occurs between CO2 and CH4; When the mass spectrometer detects that the volume flow of CO2 in the tail gas is less than 2%, the reaction is controlled to enter the CaO carbonation stage; The power of the adjustable light source was adjusted to 600-700w, and the gas distribution system was controlled to introduce 2400mL / min of Ar and 600mL / min of CO2 to remove coke and carbonate CaO. When the mass spectrometer monitored that the volume flow rate of CO2 in the exhaust gas reached 18-22%, the conversion of CaO to CaCO3 was completed.

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