阅读说明：本技术 可回热的连续型太阳能热化学固体颗粒式反应器 (Continuous solar thermochemical solid particle reactor capable of returning heat ) 是由 马天增 李鑫 常哲韶 付铭凯 张强强 任婷 吴佳妮 于 2021-09-22 设计创作，主要内容包括：本发明公开一种可回热的连续型太阳能热化学固体颗粒式反应器。技术方案是,它主要包括：还原部件、氧化部件、物料储存部件和物料输运部件。本发明利用太阳能聚光集热技术产生的高温对金属氧化物小颗粒进行加热,进而制备清洁燃料,不需要消耗化石能源,对环境污染几乎为零。采用还原腔体和氧化腔体分开的方式,有效地实现了太阳能热化学制燃料的连续性。垂直式的设计避免了金属氧化物小颗粒对玻璃面的污染,填充阻碍颗粒的方式,可以延长金属氧化物小颗粒在反应器内的停留时间,同时避免了较大温差对反应器的热冲击。通过氧化腔体内部金属氧化物小颗粒和螺杆周围金属氧化物小颗粒之间的换热,实现了对高温金属氧化物的回热,提高了固体颗粒式反应器的太阳能利用效率。(The invention discloses a continuous solar thermochemical solid particle reactor capable of returning heat. The technical scheme is that the method mainly comprises the following steps: the device comprises a reduction part, an oxidation part, a material storage part and a material conveying part. The invention heats the metal oxide small particles by utilizing the high temperature generated by the solar light-gathering and heat-collecting technology, further prepares the clean fuel, does not need to consume fossil energy, and has almost zero environmental pollution. The mode that the reduction cavity is separated from the oxidation cavity is adopted, so that the continuity of the solar thermochemical fuel production is effectively realized. The vertical design avoids the pollution of small metal oxide particles to the glass surface, the mode of filling blocking particles can prolong the retention time of the small metal oxide particles in the reactor, and simultaneously avoids the thermal shock of larger temperature difference to the reactor. Through the heat exchange between the small metal oxide particles in the oxidation cavity and the small metal oxide particles around the screw, the heat regeneration of the high-temperature metal oxide is realized, and the solar energy utilization efficiency of the solid particle type reactor is improved.)

1. The continuous solar thermochemical solid particle reactor is characterized in that the reactor adopts a mode of separating a reduction cavity (1) from an oxidation cavity (9), and the cavities are separated by adopting components such as valves and the like.

2. A recuperable continuous solar thermochemical solid particle reactor according to claim 1, characterized in that the reduction chamber (1) is sealed with double layers of quartz glass, and inert gas is introduced into the space between the double layers of glass to maintain a slight positive pressure to prevent air outside the chamber from entering the chamber and to allow the gas to take away a part of the heat.

3. A recuperable continuous solar thermochemical solid particle reactor according to claim 1, characterized in that the small metal oxide particles (7) inside the oxidation chamber (9) exchange heat by means of heat conduction with the small cold metal oxide particles (7) lifted upwards by the helical blades (20).

4. A recuperable continuous solar thermochemical solid particle reactor according to claim 1, characterized in that the small metal oxide particles (7) inside the reactor are divided into two parts, one part being reduced while the other part (7) is oxidized or transported.

5. The recuperable continuous solar thermochemical solid particle reactor according to claim 1, characterized in that the reduction chamber (1) is internally filled with hindering particles (6) having a particle size 10-10000 times the particle size of the small metal oxide particles; when sunlight exists, the partial blocking particles (6) are preheated and store heat, and when cloud cover or other fluctuation exists, the partial blocking particles (6) release heat in time; meanwhile, pores are formed among the blocking particles (6), and certain blocking is formed on the small metal oxide particles (7) while the small metal oxide particles can pass through the pores.

6. A recuperable continuous solar thermochemical solid particle reactor according to claim 1, characterized in that it uses small metal oxide particles (7) with a particle size of 1mm or less.

7. A recuperable continuous solar thermochemical solid particle reactor according to claim 1, characterized by the fact that the reduction chamber inlet (14) is at the bottom of the reduction chamber (1) and the reduction chamber outlet (15) is above the reduction chamber (1).

8. A recuperable continuous solar thermochemical solid particle reactor according to claim 7, characterized in that the oxygen bias in the lower part of the reduction chamber (1) as a whole is lower, making it easier for the small metal oxide particles (7) to lose oxygen during their fall; meanwhile, the upward flowing air flow generates suspension force on the small metal oxide particles (7) in the reduction cavity (1), so that the falling speed of the small metal oxide particles (7) is delayed, and the sunlight absorption time of the small metal oxide particles is prolonged.

Technical Field

The invention relates to a high-temperature solar thermochemical circulating device, in particular to a continuous solar thermochemical solid particle reactor capable of returning heat.

Background

The development of efficient solar energy utilization is an important method for solving the problems of energy shortage and environmental pollution nowadays. The high-temperature solar thermochemical cycle has high theoretical efficiency, and can use the advantage of full spectrum of solar energy to pay attention. As a device capable of realizing energy transfer between solar energy and chemical energy, the reasonable design and optimization of the solar thermochemical reactor play a crucial role in improving the utilization efficiency of the solar energy.

The solar thermochemical reactor as a whole can be classified into a direct type and an indirect type according to whether sunlight is in direct contact with a metal oxide. The direct reactor has the advantages of high theoretical efficiency, rapid temperature rise and the like. Conventional direct reactors include fluidized bed reactors, rotary kiln reactors, fixed bed reactors, and the like. However, the direct reactor requires a glass window for light transmission, uneven heating easily causes glass cracking, and improper sealing easily causes air entry outside the reactor or leakage of internal gas. Therefore, the problems of the connection and sealing of the glass to the other parts of the reactor are also critical to the progress of the reaction. The maintenance of a low oxygen bias in the reduction step is critical to the oxygen loss of the metal oxide and the improvement of the overall efficiency, and therefore, whether the sealing problem of the glass can be well solved is very important to the improvement of the efficiency.

At present, methods mainly adopted in the field of high-temperature solar thermochemistry are a two-temperature method and an isothermal method, wherein the isothermal method has the limitation of low theoretical efficiency. The two-temperature method is mainly divided into two steps, a reduction step and an oxidation step. Wherein the reduction step mainly utilizes the heat provided by solar energy to heat the metal oxide to about 1500 ℃ for reduction reaction. The oxidation step utilizes cooling toMetal oxide and CO at about 800 deg.C₂、H₂O or the mixture of the two is reacted to generate CO and H₂Or a mixture of both. Since the oxidation step does not require too high temperature and energy, the conventional fixed-bed reactor employs a method of directly shielding sunlight, which cannot achieve continuous operation of the reaction, and the portion of the shielded solar energy is completely wasted. Therefore, the design of the solar thermochemical reactor capable of continuously operating is more beneficial to the efficient utilization of solar energy.

For the fuel preparation by the double-temperature method solar thermochemical method, the temperature required by the oxidation step is lower than that required by the reduction step, and a large amount of energy is wasted by cooling the metal oxide in a high-temperature state to the temperature required by the oxidation reaction. Effective heat recovery is greatly beneficial to the improvement of the energy utilization efficiency.

Solar energy is intermittent and is affected by factors such as day and night, seasons and weather. Uneven solar energy can result in uneven energy distribution, large temperature gradients, and a reduction in the rate of chemical reactions. In addition, non-uniform temperature changes can also exacerbate the swelling deformation of the reactor glass window, which is more susceptible to breakage. Therefore, it is crucial to develop a stable solar thermal chemical reactor with heat storage capacity.

Compared with a fixed bed reactor, the solid particle type reactor has the advantages of large specific surface area, rapid temperature rise of reactants and the like. However, the tiny metal oxide particles also have the defects of easy glass contamination and air outlet hole blockage. When metal oxide particles are adhered to the surface of glass, the light transmission efficiency of sunlight is easily reduced.

Therefore, in order to improve the conversion efficiency from solar energy to chemical energy and develop a high-efficiency and stable solar thermochemical reactor, measures are taken to solve the problems of heat regeneration, continuity, glass sealing, glass pollution and the like, which are technical problems to be solved in the field.

Disclosure of Invention

The invention mainly aims to overcome the defects and shortcomings of the prior art, comprehensively considers the problems of glass sealing, glass pollution and the like, and provides a continuous solar thermochemical solid particle reactor which is efficient, can store heat and can regenerate heat, so that the conversion efficiency from solar energy to chemical energy is improved.

The invention adopts the following technical scheme:

a continuous type solar thermochemical solid particle reactor capable of returning heat comprises at least a reduction cavity and an oxidation cavity. The reactor adopts a mode of separating the reduction cavity (1) from the oxidation cavity (9), and parts such as valves are adopted to separate the cavities, so that the continuous operation of the solar thermochemical temperature-changing reaction is realized.

Further, the reduction cavity (1) is sealed by adopting double-layer quartz glass. And inert gas is introduced into the gap between the double-layer glass to maintain micro-positive pressure so as to prevent air outside the cavity from entering the cavity, and meanwhile, part of heat can be taken away by the part of gas.

Furthermore, the small metal oxide particles (7) in the oxidation cavity (9) exchange heat with the small cold-state metal oxide particles (7) lifted upwards by the helical blades (20) in a heat conduction mode, and heat recovery is realized. For example, the small metal oxide particles (7) are CeO₂The particle size of the particles is less than or equal to 1 mm.

Furthermore, the small metal oxide particles (7) in the reactor are divided into two parts, when one part is subjected to reduction reaction, the other part of the small metal oxide particles (7) is subjected to oxidation reaction or conveyed, and thus continuous operation of the whole cycle is realized.

Furthermore, the interior of the reduction cavity (1) is filled with barrier particles (6), and the particle size of the barrier particles is 10-10000 times of that of the small metal oxide particles. When sunlight exists, the partial blocking particles (6) are preheated and store heat, and when cloud cover or other fluctuation exists, the partial heat storage blocking particles (6) release heat in time, so that the inside of the reduction cavity (1) is kept at a higher temperature all the time, and great thermal shock to the reactor is avoided. Meanwhile, pores are formed among the blocking particles (6), and certain blocking is formed on the small metal oxide particles (7) while the small metal oxide particles can pass through the pores. The blocking particles (6) have a certain blocking effect on the small metal oxide particles (7) and prolong the length of the small metal oxide particles in the reactorWhile the gaps formed allow the passage of small metal oxide particles (7). For example, the barrier particles are tungsten particles, Al₂O₃Particles and/or SiC particles, and the like.

Furthermore, the reactor adopts small metal oxide particles (7) with the particle size of less than or equal to 1 mm. Has larger specific surface area, thereby improving the heating rate of solid particles and simultaneously improving the rate of the whole reaction.

Furthermore, the air inlet (14) of the reduction cavity is arranged at the bottom of the reduction cavity (1), and the air outlet (15) of the reduction cavity is arranged above the reduction cavity (1). The oxygen bias at the lower part of the reduction cavity (1) is lower on the whole, so that the small metal oxide particles (7) are easier to lose oxygen in the falling process. Meanwhile, the upward flowing air flow generates suspension force on the small metal oxide particles (7) in the reduction cavity (1), so that the falling speed of the small metal oxide particles (7) is delayed, and the sunlight absorption time of the small metal oxide particles is prolonged.

The invention relates to a regenerative continuous solar thermochemical solid particle reactor which mainly comprises a reduction component, an oxidation component, a material storage component and a material conveying component. Wherein the reduction part is positioned right above the oxidation part, and the reduction part is connected with the oxidation part by a valve. The material storage part is positioned below the oxidation part, and the material storage part is connected with the oxidation part through a valve. The spiral conveying part is arranged on one side of the oxidation part and the reduction part, the bottom of the spiral conveying part is inserted into the material storage part, and the upper part of the spiral conveying part is connected with the reduction part and is used for lifting small metal oxide particles in the material storage part to the reduction part.

The reduction component consists of a reduction cavity, quartz glass, a metal oxide feed inlet, a reduction cavity air outlet, blocking particles, a porous partition plate, a glass sealing air inlet and a glass sealing air outlet. In order to better seal, the quartz glass adopts double layers and is horizontally arranged in the middle position of the uppermost surface of the reduction part, and inert gas is introduced into the middle gap of the double layers of glass from the glass seal gas inlet and is discharged from the glass seal gas outlet. A positive pressure is always maintained in the middle of the double-layer glass, so that external gas is prevented from entering the reactor. Sunlight is perpendicularly incident to the interior of the reduction cavity from quartz glass. The small metal oxide particles enter the reactor from a metal oxide feed inlet arranged on one side of the reduction cavity and then fall by gravity. The blocking particles placed on the porous partition at the bottom of the reduction unit have a certain blocking effect on the falling small metal oxide particles, and the residence time of the small metal oxide particles in the reactor can be prolonged. The blocking particles are placed at the bottom of the reduction cavity, the blocking particles are heated by sunlight which is vertically incident to quartz glass at any time, when weather changes such as cloud shading occur, the blocking particles release the stored heat, the inside of the reactor is maintained to have higher temperature, and meanwhile, thermal shock caused by severe temperature changes in the reduction cavity to the reactor is also avoided. The gas enters the reduction cavity from a reduction cavity gas inlet arranged at the bottom of the reduction cavity, the gas flowing from bottom to top has certain suspension force on small metal oxide particles in the reduction cavity, and meanwhile, the better vacuum degree of the reduction component can be maintained. The gas is discharged from a gas outlet of the reduction cavity arranged at the top of the reduction cavity. The small metal oxide particles are heated in the reduction cavity to perform reduction reaction, and then are discharged along the pores of the porous partition plate.

The oxidation part consists of an oxidation cavity, an oxidation cavity air inlet and an oxidation cavity air outlet. The small metal oxide particles which have undergone the reduction reaction in the reduction cavity fall into the oxidation cavity under the action of gravity. Reaction gas enters the oxidation part from the gas inlet of the oxidation cavity to perform oxidation reaction with the small metal oxide particles, and gas generated by the reaction is discharged from the gas outlet of the oxidation cavity.

The material storage part consists of a particle storage cavity. The small metal oxide particles after reaction in the reduction part fall to the particle storage cavity under the action of gravity for temporary storage.

The material conveying component consists of a screw, a helical blade and a motor. The screw is inserted into the center of the particle storage cavity and is driven by the motor to rotate, the helical blades on the screw lift the small metal oxide particles in the particle storage cavity to the height of the reduction cavity, and then the small metal oxide particles enter the reduction part through the metal oxide feed inlet to complete the whole cycle.

Has the advantages that:

1. the small metal oxide particles with the particle size of less than or equal to 1mm are adopted, the heating rate is improved, and the reaction area is increased;

2. the sunlight adopts a vertical incidence mode, so that the glass window is prevented from being infected by small metal oxide particles;

3. the mode of filling blocking particles is adopted for heat storage, so that the large impact of a large temperature gradient on the reactor is reduced, the stability and the reliability of the reactor are improved, and the blocking effect prolongs the retention time of small metal oxide particles;

4. the continuous operation of the whole cycle is realized by adopting a mode of separating the oxidation reaction and the reduction reaction;

5. the heat recovery of the small solid metal oxide particles is realized by adopting a heat conduction mode;

6. and the complete cyclic reaction of small metal oxide particles is realized by adopting a helical blade material lifting device.

Drawings

FIG. 1 is a schematic structural view of the present invention;

fig. 2 is a schematic diagram of the working process of the present invention.

In the figure: 1 reduction cavity, 2 first quartz glass, 3 second quartz glass, 4 glass sealed air inlets, 5 glass sealed air outlets, 6 blocking particles, 7 small metal oxide particles, 8 metal oxide feed inlets, 9 oxidation cavity, 10 first sealed valves, 11 second sealed valves, 12 particle storage cavities, 13 screw rods, 14 reduction cavity air inlets, 15 reduction cavity air outlets, 16 oxidation cavity air inlets, 17 oxidation cavity air outlets, 18 connecting pieces, 19 motors, 20 spiral blades, 21 material conveying cavities, 22 multi-pore partition plates, 23 heliostats and 24 reflectors.

Detailed Description

The invention is further described with reference to the following drawings and detailed description.

The invention relates to a continuous solar thermochemical solid particle reactor main body capable of returning heatIs used for the solar high-temperature thermochemical preparation of CO and H₂Or a mixture of both. As shown in FIG. 2, the reactor of the present invention is installed near the focal point of the solar mirror field, and the sunlight enters the reactor by vertical incidence.

As shown in fig. 1-2, the continuous type solar thermochemical solid particle reactor of the invention, which can be regenerated, mainly comprises a reduction part, an oxidation part, a material storage part and a material transport part. Wherein the reduction part is positioned right above the oxidation part, and the reduction part is connected with the oxidation part by a valve. The material storage part is positioned below the oxidation part, and the material storage part is connected with the oxidation part through a valve. The spiral conveying part is arranged on one side of the oxidation part and the reduction part, the bottom of the spiral conveying part is inserted into the material storage part, and the upper part of the spiral conveying part is connected with the reduction part and is used for lifting small metal oxide particles in the material storage part to the reduction part.

The reduction part includes: the device comprises a reduction cavity 1, first quartz glass 2, second quartz glass 3, blocking particles 6, a porous partition plate 22, a metal oxide feed inlet 8, a reduction cavity air inlet 14, a reduction cavity air outlet 15, a glass sealing air inlet 4 and a glass sealing air outlet 5. The reduction chamber 1 is in the shape of a quadrangular frustum of a pyramid and is mainly made of a ceramic material. For better sealing, the quartz glass is horizontally arranged at the middle position of the uppermost surface of the reduction part in a double-layer mode, and inert gas is introduced into the middle gap of the double-layer glass through a glass sealing gas inlet 4 and is discharged from a glass sealing gas outlet 5. The quartz glass is used as a double layer, i.e. a first quartz glass 2 and a second quartz glass 3. A positive pressure is always maintained in the middle of the double-layer glass, so that external gas is prevented from entering the reactor. The solar light is vertically incident to the interior of the reduction chamber 1 through the first quartz glass 2 and the second quartz glass 3 to be heated. The small metal oxide particles 7 enter the reduction chamber 1 through a metal oxide feed inlet 8 arranged on one side of the reduction chamber 1 and then fall by gravity. Barrier particles 6 (particle type is tungsten particles, Al particles) having a particle diameter 10-10000 times of that of the small metal oxide particles are placed on the porous partition plate 22 at the bottom of the reduction chamber 1₂O₃Particles, SiC material dominant) versus falling metal oxidesSmall particles 7 (in CeO)₂Particles as an example, the CeO₂The grain diameter of the grains is less than or equal to 1mm) has certain barrier effect, and the retention time of the grains in the reactor can be prolonged. Reduction cavity 1 bottom is placed and is hindered granule 6, and the sunlight through first quartz glass 2 and 3 vertical incidence of second quartz glass heats hindering granule 6 at any time, and when weather changes such as the cloud shelters from appearing, hinders granule 6 and releases the heat that stores, maintains reduction cavity 1 inside and has higher temperature, also avoids violent temperature variation to the thermal shock that the reactor caused simultaneously. The gas enters the reduction cavity 1 from a reduction cavity gas inlet 14 arranged at the bottom of the reduction cavity 1, the gas flowing from bottom to top has certain suspension force on the small metal oxide particles 7 in the reduction cavity 1, and meanwhile, the better vacuum degree of the reduction component can be maintained. The gas is discharged from a gas outlet 15 of the reduction cavity arranged at the top of the reduction part. The small metal oxide particles 7 are heated inside the reduction part, undergo a reduction reaction, and are then discharged along the pores of the porous partition 22.

The reduction chamber 1 is connected with the oxidation chamber 9 through a connecting piece 18 and a first sealing valve 10 in sequence.

The oxidation part consists of an oxidation cavity 9, an oxidation cavity air inlet 16 and an oxidation cavity air outlet 17. The small metal oxide particles 7 that have undergone the reduction reaction inside the reduction part fall under the action of gravity inside the oxidation chamber 9. Reaction gas H₂O/CO₂The gas enters the oxidation cavity 9 from the oxidation cavity gas inlet 16 to react with the metal oxide small particles 7, and the gas generated by the reaction is discharged from the oxidation cavity gas outlet 17.

The oxidation chamber 9 is connected to a particle storage chamber 12 via a second sealing valve 11.

The material storage member is comprised of a particle storage chamber 12. The small metal oxide particles 7 which are reacted in the reduction part fall to the particle storage cavity 12 under the action of gravity for temporary storage.

The material conveying component consists of a screw 13, a helical blade 20, a motor 19 and a material conveying cavity 21. Wherein, the screw 13 is inserted into the center of the particle storage cavity 12 and is driven by the motor 19 to rotate, the helical blade 20 on the screw 13 lifts the metal oxide small particles 7 in the particle storage cavity 12 to the height of the reduction part, and then the metal oxide small particles enter the reduction cavity 1 through the metal oxide feed inlet 8 to complete the whole cycle. The outer wall surface of the material conveying cavity 21 is in contact with the outer wall surface of the oxidation cavity 9, and the small metal oxide particles 7 in a cold state are lifted upwards and are thermally recycled with the small metal oxide particles 7 in a high temperature through heat conduction.

The specific operation flow of the device is as follows: sunlight is reflected by the heliostat 23 and the reflector 24 to become vertically incident light, and the collected light is incident into the reduction cavity 1 through the double-layer glass window to heat the interior of the reduction cavity 1. The blocking particles 6 are pre-filled inside the reduction chamber 1, and the incident sunlight first heats the blocking particles 6 and keeps the temperature inside the chamber high. Inert gas enters the reactor through the reduction cavity gas inlet 14 to take away oxygen inside the reduction cavity 1, so that a better vacuum degree is maintained inside the reduction cavity 1. When the temperature inside the reduction chamber 1 reaches a nearly stable state, the motor 19 is started, and the screw 13 and the helical blade 20 are driven to rotate, so that the metal oxide small particles 7 pre-loaded in the particle storage chamber 12 are conveyed to the position of the metal oxide feed port 8. Under the dual action of gravity and the suspension force of the ascending air flow, the small metal oxide particles 7 slowly fall and absorb the incident sunlight to increase the temperature. The rising air flow also retards the falling speed of the small metal oxide particles 7 and increases the time during which the small metal oxide particles 7 are exposed to sunlight. At this time, the inert gas flowing from bottom to top takes away the oxygen generated by the metal oxide particles 7 in time, and a better vacuum environment is maintained in the cavity. At a lower oxygen bias and higher temperature, the small metal oxide particles 7 complete the reduction reaction. At this time, the first sealing valve 10 is opened to allow the falling metal oxide particles 7 to flow therethrough and enter the inside of the oxidation chamber 9. When all the small metal oxide particles 7 pass through the first sealing valve 10, the first sealing valve 10 is closed. The metal oxide small particles 7 entering the oxidation cavity 9 and the oxidation cavityThe wall surface 9 is subjected to heat exchange, and a part of heat inside the small metal oxide particles 7 is exchanged to the outer wall surface of the material conveying cavity 21 and further transferred to the small countercurrent upward low-temperature metal oxide particles 7. When the temperature of the small metal oxide particles 7 in the oxidation cavity 9 is reduced to the temperature required by the oxidation reaction, the air inlet 16 of the oxidation cavity is opened, and water vapor or CO is introduced₂The gas reacts with the small metal oxide particles 7 therein. In which H is produced₂Or the CO gas is discharged from the oxidation chamber gas outlet 17. The second sealing valve 11 is opened, and the small metal oxide particles 7 after the oxidation reaction fall into the particle storage cavity 12 under the action of gravity. Under the drive of the helical blade 20, the part of the metal oxide small particles 7 is lifted slowly and then enters the interior of the reduction cavity 1 through the metal oxide feed inlet 8 to start a new cycle.

The device can realize continuous thermochemical cycle reaction, wherein the small metal oxide particles 7 are filled into the reactor in advance and divided into two parts, and when one part of the small metal oxide particles 7 are subjected to reduction reaction, the other part of the small metal oxide particles 7 are subjected to oxidation reaction.

The invention has not been described in detail and is part of the common general knowledge of a person skilled in the art. The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and the preferred embodiments are not exhaustive and do not limit the invention to the precise embodiments described. Various modifications and improvements of the technical solution of the present invention may be made by those skilled in the art without departing from the spirit of the present invention, and the technical solution of the present invention is to be covered by the protection scope defined by the claims.