A solar thermochemical reactor based on a biomimetic skeleton

Abstract

A solar thermochemical reactor based on bionic skeleton, comprising a reactor shell, a rotating shaft vertically penetrating the middle of the reactor shell, a plurality of transverse partitions arranged at intervals on the outer periphery of the rotating shaft, a plurality of longitudinal partitions connected between the transverse partitions, and AL2O3 bionic skeletons uniformly arranged between the transverse partitions and the longitudinal partitions, wherein the transverse partitions, the longitudinal partitions and the AL2O3 bionic skeletons rotate with the rotating shaft; sunlight is collected and reflected into a reactor observation window, the reactor absorbs heat to reach the required temperature of a thermochemical reaction, water vapor is introduced from an air inlet and dispersed by a gas homogenizer, the rotating shaft drives the transverse partitions, the longitudinal partitions and the AL2O3 bionic skeletons to rotate synchronously, the gas fully contacts and absorbs heat from the oxygen carriers attached to the AL2O3 bionic skeletons, in this process, the metal elements or low-valence metal oxides are oxidized to high-valence metal oxides MoO3, and hydrogen gas is generated at the same time, which is discharged from an air outlet; the uniformity of heat flow in the reactor, the reaction contact area and the local gas flow are effectively improved, and the thermochemical reaction efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of solar thermal utilization and energy storage equipment technology, specifically a biomimetic solar thermochemical reactor. Background Technology

[0002] Solar energy is an abundant renewable energy source. The amount of solar energy reaching the Earth's surface every hour could meet humanity's energy needs for a year. Solar energy resources are characterized by their unlimited reserves, intermittency, low heat flux density, and cleanliness. Many developed countries have elevated renewable energy sources such as solar energy from supplementary energy to strategic alternative energy sources.

[0003] Currently, energy storage technologies mainly include sensible heat, latent heat, and thermochemical energy storage, among which thermochemical energy storage is the most promising. Thermochemical energy storage systems have the advantages of high energy density and low energy loss. Solar thermochemistry is a very promising energy storage technology that converts thermal energy into chemical energy. Thermochemical energy storage is key to solving the problems of low heat flow and intermittency inherent in solar energy. Thermochemical energy storage mainly takes place in a reactor, and the process includes: ① a heliostat field focuses sunlight and reflects it onto the reactor's opening; ② a chemical reaction – a thermochemical cycle reaction using metal oxides at high temperature stores solar energy in the products. For example, under catalytic conditions, CH4 reacts with water vapor at 1000℃ to produce H2, and the thermochemical reactor is the core equipment for realizing this process. Traditional chamber reactors suffer from problems such as thermal deformation, reaction channel blockage, and catalyst carbon buildup, which severely reduce the efficiency of thermochemical reactions and pose safety risks to the conversion system. Therefore, developing efficient and stable solar thermochemical reactors is an urgent problem to be solved in this field.

[0004] Patent application CN108187598B discloses a solar thermochemical reactor device with a rotating airflow group structure, including a reactor shell, a reaction chamber inside the reactor shell, the reaction chamber being an inverted cone shape, a bottom plate at the lower opening of the reaction chamber, at least three air inlets on the bottom plate, the air inlets being evenly arranged circumferentially along the plane of the bottom plate, an air inlet pipe communicating with the interior of the reaction chamber below the air inlets, and each air inlet pipe having a spiral blade inside.

[0005] This patent application describes a reactor with air inlets evenly distributed at the bottom edge. During the spiral ascent of the feed gas, the solid particles in the feed gas pass through the central region of the reactor under centrifugal force, effectively absorbing the high-density solar energy flow in the central region. However, the uniformity of the reaction in the main body of the reaction chamber is difficult to control, affecting the thermochemical reaction efficiency. By gradually increasing the cross-sectional area of ​​the reactor, the rotating airflow gradually disperses and cross-mixes, the forward speed gradually decreases, and the mixing intensity gradually increases, increasing the residence time of the feed gas near the optical window to improve the overall thermal conversion efficiency of the system. However, this can easily cause thermal deformation of the reaction chamber and carbon buildup on the catalyst. Summary of the Invention

[0006] In order to overcome the defects of the existing technology, the present invention aims to provide a solar thermochemical reactor based on a biomimetic skeleton. By setting a special structure of longitudinal partitions, transverse partitions and Al2O3 biomimetic skeleton in the reaction chamber, the uniformity of gas in the reaction chamber is ensured, the thermochemical reaction area is increased, and the problems of low chemical reaction rate, blockage of reaction channels and non-uniform heat flow distribution in existing reactors can be solved.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A solar thermochemical reactor based on a biomimetic skeleton includes a reactor shell 12, which includes an upper cover 1, a lower cover 4, and a cylindrical cavity 3 between the upper cover 1 and the lower cover 4. The upper cover 1 has an air outlet 7 at its upper part, and the lower cover 4 has an air inlet 5 at its lower part. The cylindrical cavity 3 has an observation window 2 on its side wall. The reactor shell 12 has a rotating shaft 8 that vertically penetrates its inner cavity. Multiple transverse partitions 6 are spaced apart on the outer periphery of the rotating shaft 8. Multiple longitudinal partitions 11 are connected between the transverse partitions 6. An Al2O3 biomimetic skeleton 10 is evenly arranged between the transverse partitions 6 and between the longitudinal partitions 11. The transverse partitions 6, longitudinal partitions 11, and Al2O3 biomimetic skeleton 10 rotate with the rotating shaft 8.

[0008] The cylindrical cavity 3 has an observation window 2 on its side wall, and gas homogenizers 9 are provided on the transverse partitions 6 connected to both ends of the cylindrical cavity 3.

[0009] The transverse partition 6 and the longitudinal partition 11 are evenly provided with a number of small holes with a diameter of 2-5mm.

[0010] The Al2O3 skeletons 10 between the transverse partitions 6 and between the longitudinal partitions 11 are perpendicular to each other.

[0011] The inner wall of the reactor shell 12 is coated with transition metal oxide MoO3.

[0012] The surface of the Al2O3 biomimetic framework 10 is coated with an oxygen carrier.

[0013] The oxygen carrier is The active components are CaO, MnO, and Ca. 0.5 Mn 0.5 Any one of O can be used as the dispersion medium, and the ratio of active component to dispersant is 1.5-1.0:1.

[0014] The shape of the Al2O3 biomimetic framework 10 is obtained by continuously generating Hilbert-Peano curves using a recursive algorithm, drawing curve diagrams, and then performing laser etching on an Al2O3 substrate according to the drawn curve diagrams.

[0015] The specific steps of the recursive algorithm to continuously generate and plot Hilbert-Peano curves are as follows: S1: Set the recursion depth n; S2: Determine the range of the curve, i.e., X min Y min X max Y max That is, the initial square, where X min Y min X max Y max These are the coordinates of the four vertices of the initial square; S3: Divide the initial square into four equal parts along the orthogonal direction, and then divide its side length into 2n equal parts. The grid spacing is then: dx = (X ma -X min ) / (2*2n),dy=(Y max - Y min ) / (2*2n); S4: Calculate the starting coordinates of the curve, i.e., X = X min +dx,Y= Y min +dy; S5: Call the recursive algorithm and push the information onto the stack until n=1, then release the stack and plot the curve.

[0016] The Hilbert-Peano curve was plotted, and the Al2O3 substrate was laser-etched to obtain the Al2O3 biomimetic framework 10 by a custom scaling ratio.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The Al2O3 biomimetic framework 10 of the present invention is tree-shaped, and the surface of the Al2O3 biomimetic framework 10 is attached with an oxygen carrier catalyst. The oxygen carrier absorbs heat uniformly. The tree-shaped shape of the Al2O3 biomimetic framework 10 increases the thermochemical reaction area and greatly improves the efficiency of the solar thermochemical reactor.

[0018] 2. The cross-sectional partitions 6 and longitudinal partitions 11, which support the Al2O3 biomimetic skeleton, rotate synchronously with the reactor's rotation axis 8. This increases the thermochemical reaction area and ensures the uniformity of energy absorption and conversion within the reactor chamber.

[0019] 3. The small holes evenly distributed in the transverse partition 6 and the longitudinal partition 11 are used to allow the reaction gas to pass through and to disperse the gas evenly, so as to maintain the unobstructed reaction channel and the uniformity of gas distribution.

[0020] 4. The inner wall of the reactor shell 12 is coated with MoO3, a transition metal oxide with a high melting point and high reflectivity, which allows for high reflectivity in the visible light and infrared radiation bands, thereby reducing the heat loss of the reactor.

[0021] In summary, this invention provides a high-temperature reaction device for solar thermochemical reaction processes. This reactor overcomes the problems of non-uniform heat flow distribution, small reaction surface area, and low reactor efficiency in traditional reactors, and greatly improves the efficiency of solar thermochemical reactions. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] In the diagram: 1—Top cover; 2—Observation window; 3—Cylindrical cavity; 4—Lower cover; 5—Air inlet; 6—Horizontal partition; 7—Air outlet; 8—Rotating shaft; 9—Gas homogenizer; 10—Al2O3 biomimetic skeleton; 11—Longitudinal partition; 12—Reactor shell.

[0024] Figure 1 This is a schematic diagram of the structure of the present invention.

[0025] Figure 2 This is a partial structural diagram of the present invention.

[0026] Figure 3 This is a schematic diagram of the morphology of the Al2O3 biomimetic framework 10 in this invention.

[0027] Figure 4 This invention provides a method for designing the morphology of the Al2O3 biomimetic framework 10. Detailed Implementation

[0028] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present disclosure.

[0029] See Figure 1 , Figure 2 A solar thermochemical reactor based on a biomimetic skeleton includes a reactor shell 12, which includes an upper cover 1, a lower cover 4, and a cylindrical cavity 3 between the upper cover 1 and the lower cover 4. The upper cover 1 has an air outlet 7 at its upper part, and the lower cover 4 has an air inlet 5 at its lower part. The cylindrical cavity 3 has an observation window 2 on its side wall. The reactor shell 12 has a rotating shaft 8 that vertically penetrates its inner cavity in the center. Multiple transverse partitions 6 are spaced apart on the outer periphery of the rotating shaft 8. Multiple longitudinal partitions 11 are connected between the transverse partitions 6. An Al2O3 biomimetic skeleton 10 is evenly arranged between the transverse partitions 6 and between the longitudinal partitions 11. The transverse partitions 6, longitudinal partitions 11 and Al2O3 biomimetic skeleton 10 rotate with the rotating shaft 8.

[0030] The cylindrical cavity 3 has an observation window 2 on its side wall, and gas homogenizers 9 are provided on the transverse partitions 6 connected to both ends of the cylindrical cavity 3.

[0031] The transverse partition 6 and the longitudinal partition 11 are uniformly provided with n small holes with a diameter of 2-5mm, which are used to allow the reaction gas to pass through and to make the gas evenly dispersed, so as to maintain the unobstructed reaction channel and the uniformity of gas distribution.

[0032] The Al2O3 biomimetic framework 10 between the transverse partitions 6 and between the longitudinal partitions 11 is perpendicular to each other; the design of the transverse partitions 6, longitudinal partitions 11 and Al2O3 biomimetic framework 10 increases the contact time and area between the gas and the catalyst, while the Reynolds number Re (1800-3000) of the local gas flow in the cylindrical cavity 3 is conducive to enhanced heat transfer in the reactor.

[0033] The inner wall of the reactor shell 12 is coated with transition metal oxide MoO3. MoO3 has a high melting point and high reflectivity, which allows for high reflectivity in the visible light and infrared radiation bands, thereby reducing the heat loss of the reactor.

[0034] The surface of the Al2O3 biomimetic framework 10 is coated with an oxygen carrier.

[0035] The oxygen carrier is The active components are CaO, MnO, and Ca. 0.5 Mn 0.5 Any one of O can be used as the dispersion medium, and the ratio of active component to dispersant is 1.5-1.0:1.

[0036] See Figure 3The morphology of the Al2O3 biomimetic framework 10 is obtained by continuously generating Hilbert-Peano curves using a recursive algorithm, and then laser etching is performed on an Al2O3 substrate according to the plotted curves. The Al2O3 biomimetic framework 10 has a tree-like shape, and an oxygen-carrying catalyst is attached to its surface. The oxygen carrier uniformly absorbs heat, and the tree-like shape of the Al2O3 biomimetic framework 10 increases the thermochemical reaction area, greatly improving the efficiency of the solar thermochemical reactor.

[0037] See Figure 4 The specific steps of the recursive algorithm to continuously generate and plot Hilbert-Peano curves are as follows: S1: Set the recursion depth n; S2: Determine the range of the curve, i.e., X min Y min X max Y max That is, the initial square, where X min Y min X max Y max These are the coordinates of the four vertices of the initial square; S3: Divide the initial square into four equal parts along the orthogonal direction, and then divide its side length into 2n equal parts. The grid spacing is then: dx = (X ma -X min ) / (2*2n),dy=(Y max - Y min ) / (2*2n); S4: Calculate the starting coordinates of the curve, i.e., X = X min +dx,Y= Y min +dy; S5: Call the recursive algorithm and push the information onto the stack until n=1, then release the stack and plot the curve.

[0038] To obtain the Al2O3 biomimetic framework 10, a Hilbert-Peano curve was plotted and laser etching was performed on an Al2O3 substrate using a custom scaling ratio.

[0039] The working principle of this invention is as follows: The heliostat field focuses sunlight and reflects it onto the quartz glass observation window 2 of the reactor shell. The reactor absorbs heat to reach the temperature required for the thermochemical reaction. In the high-temperature environment isolated from oxygen, the high-temperature resistant transition metal oxide MoO3 coated on the inner wall of the reactor shell 12 is reduced to elemental metal or low-valence metal oxide, releasing oxygen. Water vapor is introduced from the inlet 5 and dispersed by the gas homogenizer 9. The hot gas rises and, driven by the rotating shaft 8, passes through the transverse partition 6, longitudinal partition 11, and Al2O3 biomimetic skeleton 10, fully contacting the oxygen carrier attached to the Al2O3 biomimetic skeleton 10 to absorb heat. During this process, the elemental metal or low-valence metal oxide is oxidized to high-valence metal oxide MoO3, while hydrogen is generated. Gas-solid separation occurs, and the gas is discharged from the outlet 7.

[0040] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0041] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0042] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A solar thermochemical reactor based on a biomimetic skeleton, comprising a reactor shell (12), the reactor shell (12) comprising an upper cover (1), a lower cover (4) and a cylindrical cavity (3) between the upper cover (1) and the lower cover (4), the upper cover (1) having an air outlet (7) at its upper part and the lower cover (4) having an air inlet (5) at its lower part, characterized in that: The reactor shell (12) is provided with a rotating shaft (8) that runs vertically through its inner cavity. Multiple transverse partitions (6) are spaced apart on the outer periphery of the rotating shaft (8). Multiple longitudinal partitions (11) are connected between the transverse partitions (6). An Al2O3 biomimetic skeleton (10) is evenly arranged between the transverse partitions (6) and between the longitudinal partitions (11). The transverse partitions (6), longitudinal partitions (11) and Al2O3 skeleton (10) rotate with the rotating shaft (8). Small holes are evenly distributed on the transverse partitions (6) and longitudinal partitions (11). An oxygen carrier is attached to the surface of the Al2O3 biomimetic skeleton (10).

2. The solar thermochemical reactor based on a biomimetic framework according to claim 1, characterized in that: The cylindrical cavity (3) has an observation window (2) on its side wall, and gas homogenizers (9) are provided on the transverse partitions (6) connected to both ends of the cylindrical cavity (3).

3. The solar thermochemical reactor based on a biomimetic framework according to claim 1, characterized in that: The small holes with a diameter of 2-5 mm are evenly distributed on the transverse partition (6) and longitudinal partition (11).

4. A solar thermochemical reactor based on a biomimetic framework according to claim 1, characterized in that: The AL2O3 biomimetic skeleton (10) between the transverse diaphragms (6) and between the longitudinal diaphragms (11) is perpendicular to each other.

5. A solar thermochemical reactor based on a biomimetic framework according to claim 1, characterized in that: The inner wall of the reactor shell (12) is coated with transition metal oxide MoO3.

6. A solar thermochemical reactor based on a biomimetic framework according to claim 5, characterized in that: The oxygen carrier is The active components are CaO, MnO, and Ca. 0.5 Mn 0.5 Any one of O can be used as the dispersion medium, and the ratio of active component to dispersant is 1.5-1.0:

1.

7. A solar thermochemical reactor based on a biomimetic framework according to any one of claims 1 and 4, characterized in that: The shape of the Al2O3 biomimetic framework (10) is generated by continuously generating Hilbert-Peano curves using a recursive algorithm.

8. A solar thermochemical reactor based on a biomimetic skeleton according to claim 7, characterized in that: The specific steps of the recursive algorithm to continuously generate Hilbert-Peano curves are as follows: S1: Set the recursion depth n; S2: Determine the range of the curve, i.e., X min Y min X max Y max That is, the initial square, where X min Y min X max Y max These are the coordinates of the four vertices of the initial square; S3: Divide the initial square into four equal parts along the orthogonal direction, and then divide its side length into 2n equal parts. The grid spacing is then: dx = (X ma -X min ) / (2*2n),dy=(Y max - Y min ) / (2*2n); S4: Calculate the starting coordinates of the curve, i.e., X = X min +dx,Y= Y min +dy; S5: Call the recursive algorithm and push the information onto the stack until n=1, then release the stack and plot the curve.

9. A solar thermochemical reactor based on a biomimetic framework according to claim 8, characterized in that: The Hilbert-Peano curve was plotted, and the Al2O3 substrate was laser-etched to obtain the Al2O3 biomimetic skeleton (10) by custom scaling.

Images