Endothermic reaction system and control method for hot air heating

Abstract

Embodiments of the present invention provide an endothermic reaction system and control method using hot air heating, belonging to the field of energy utilization. The endothermic reaction system using hot air heating includes a heat source, an endothermic reactor, a circulation channel connecting the heat source and the endothermic reactor, and an induced draft fan and damper disposed within the circulation channel. The induced draft fan is used to generate air flow, and the damper is used to regulate the air flow, so that the outlet cold energy is returned to the heat energy inlet of the endothermic reactor in the form of cold air, and the heat energy is delivered to the endothermic reactor in the form of hot air. The control method for controlling the endothermic reaction system using hot air heating includes the following steps: monitoring temperature change information of the hot air near the induced draft fan; and, in response to the temperature change information, changing the driving force of the induced draft fan and / or the heat source outlet regulating mechanism to ensure that the reaction temperature fluctuation and / or reaction load fluctuation of the endothermic reactor are within a preset range. The present invention uses air as the heat medium, reduces the number of heat transfers, facilitates detection and control, improves heat transfer efficiency, and is low-cost.

Description

Technical Field

[0001] The present invention relates to the technical field of energy utilization, and in particular to an endothermic reaction system for hot air heating and a control method thereof. Background Art

[0002] With the continuous deepening of energy research, how to use energy efficiently is an urgent problem to be solved. An endothermic reactor is a device that uses thermal energy to react. Generally speaking, there is a heat supply medium inside it, and the heat supply medium is used as a heat conducting medium to transfer heat energy to the heat-requiring part. In the prior art, when an endothermic reactor needs external heat energy, it is mostly provided in the form of electric heating or gas heating, and in the form of fluids such as hot oil and hot water, that is, the first heat conduction is performed with the fluid and the second heat conduction is performed with the heat supply medium. However, since the fluid is limited by the heat transfer between the partitions, considering the complex internal structure of the endothermic reaction system, in order to effectively obtain heat energy, it is necessary to set up a complex piping system and temperature control process, and the fluid cannot directly contact the inside of the endothermic reactor. In addition, the secondary conduction makes the heat loss larger, and the heat energy transfer efficiency is not high. In addition, the insufficient utilization of clean energy and waste heat resources makes the operating cost high. Summary of the Invention

[0003] The purpose of the embodiments of the present invention is to provide an endothermic reaction system and control method using hot air heating. The system has a simple structure and a simple control method. It uses air as a heat transfer medium to reduce the number of heat transfers and facilitate detection and control, thereby improving the energy utilization efficiency of the endothermic reaction system and reducing costs in terms of equipment, energy consumption, etc.

[0004] In order to achieve the above-mentioned objectives, an endothermic reaction system for hot air heating provided in an embodiment of the present invention includes: a heat source for providing thermal energy; an endothermic reactor for performing an endothermic reaction to supply energy to external equipment and generate outlet cold energy; a circulation channel connecting the heat source and the endothermic reactor, for delivering thermal energy to the endothermic reactor, and for delivering the outlet cold energy back to the heat energy inlet of the endothermic reactor; an induced draft fan arranged in the circulation channel, for generating air flow, so that the outlet cold energy is delivered in the form of cold air and / or the heat energy is delivered in the form of hot air; and a heat source outlet regulating mechanism, including a damper, the damper opening of which is adjustable and arranged inside the circulation channel, for regulating the air flow.

[0005] Optionally, the side wall of the endothermic reactor is provided with an air outlet and an air inlet, which are connected to the interior of the endothermic reactor; at least one induced draft fan is close to the air outlet, and at least one induced draft fan is close to the air inlet.

[0006] Optionally, the circulation channel includes a first channel, a second channel and a third channel that connects the first channel and the second channel at the same time. The first channel sends hot air to the endothermic reactor, and the second channel sends cold air to the first channel via the third channel.

[0007] Optionally, the damper is provided at the intersection of the second channel and the third channel; or, the damper is provided at the intersection of the first channel and the third channel.

[0008] Optionally, the heat source is one of a heat storage body, a fuel engine and a solid oxide battery, and the temperature of the heat source is 200~600℃.

[0009] Optionally, the endothermic reaction system further includes a heat-insulating shell, which is arranged outside the endothermic reactor, and a vacuum environment or heat-dissipating thermal resistance material is provided between the heat-insulating shell and the endothermic reactor.

[0010] Optionally, the shape of the endothermic reactor is a cube or a cylinder, the catalyst bed temperature in the endothermic reaction is 200~450℃, and the endothermic reaction is a dehydrogenation reaction after hydrogen storage of the organic liquid, including dehydrogenation of N-alkylcarbazole after hydrogenation, dehydrogenation of hydrogenated benzyltoluene, dehydrogenation of hydrogenated bipyridine, dehydrogenation of hydrogenated-N-alkylindole, dehydrogenation of 1,4-butanediol to γ-butyrolactone, dehydrogenation of propane to propylene, dehydrogenation of methanol to methyl formate, and dehydrogenation of ethanol to acetaldehyde or ethyl acetate.

[0011] Optionally, the endothermic reactor includes: a shell side, which is used to provide an internal space of the endothermic reactor, and the shell side is connected to the circulation channel; a spoiler device, which includes a plurality of spoiler surfaces with pores, and the spoiler surfaces are horizontally arranged in the shell side; and a plurality of fin tubes, which pass through the pores of the spoiler surfaces and are vertically arranged inside the shell side, and the interior of the fin tubes is used for reaction.

[0012] Optionally, the fins and / or flow-turbulating surfaces of the upper finned tubes are more densely distributed than those of the lower finned tubes of the endothermic reactor.

[0013] Optionally, the endothermic reaction system also includes a heat compensation device and / or an exhaust gas utilization device; the heat compensation device is connected to the endothermic reactor through a circulation channel to supplement thermal energy; the exhaust gas utilization device is connected to the endothermic reactor to collect and utilize the gas generated after the reaction of the endothermic reactor.

[0014] On the other hand, the control method of the endothermic reaction system with hot air heating provided by the present invention includes the following steps: monitoring the temperature change information of the hot air near the induced draft fan; and changing the driving force of the induced draft fan and / or the heat source outlet regulating mechanism in response to the temperature change information, so that the reaction temperature fluctuation and / or reaction load fluctuation of the endothermic reactor are within a preset range, so that the endothermic reaction can provide energy for external equipment.

[0015] Optionally, in response to temperature change information, changing the driving force of the induced draft fan and / or the heat source outlet regulating mechanism also includes the following steps: presetting a hot air limit; when the temperature of the hot air is higher than the hot air limit, changing the driving force to reduce the damper opening and at the same time reducing the driving force of the induced draft fan; and when the temperature of the hot air is lower than the hot air limit, changing the driving force to increase the damper opening and at the same time increasing the driving force of the induced draft fan.

[0016] Optionally, when the heat source is a heat storage body and the heat storage body is powered by non-stable resources, before monitoring the temperature change information of the hot air near the induced draft fan, there is also the following control process: when it is detected that the non-stable resources are insufficient, the heat storage body is used to supply heat, the circulation channel is opened, and the induced draft fan and / or the heat source outlet regulating mechanism is started; when it is detected that the non-stable resources are sufficient, the non-stable resources are stored in the heat storage body, the heat storage body is heated to a preset temperature, and whether to open or close the circulation channel is determined according to the energy demand of the external equipment.

[0017] Through the above technical solution, the present invention couples the endothermic reactor and the heat source through a circulation channel. No additional heat-conducting medium and a matching heat-conducting device are required in the endothermic reactor. Heat energy and cold energy are transferred and circulated only in the form of wind. The internal temperature is controllable and stable, which is convenient for detection and control, and the number of heat transfers is reduced, which simplifies the structure of the traditional endothermic reactor and improves the heat transfer efficiency. At the same time, the backflow of cold air can reduce the temperature at the hot air inlet, thereby maintaining the low longitudinal temperature difference of the endothermic reactor; at the same time, the air volume is increased to generate turbulence, increase the heat transfer coefficient, and protect the equipment; in addition, based on the principle of pressure difference, the circulation channel is assisted by an induced draft fan to generate air flow, and the damper changes the backflow of cold air to adjust the air flow. The equipment is simple and highly controllable.

[0018] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the embodiments of the present invention, but do not constitute a limitation of the embodiments of the present invention. In the accompanying drawings:

[0020] Figure 1 It is a schematic diagram of the interaction of the main components of the endothermic reaction system for hot air heating;

[0021] Figure 2 Is control such as Figure 1 Basic flow chart of the control method;

[0022] Figure 3 1 is a schematic structural diagram of an endothermic reaction system using hot air heating;

[0023] Figure 4This is a schematic structural diagram of Example 2 of an endothermic reaction system using hot air heating;

[0024] Figure 5 It is a structural diagram of Example 3 of the endothermic reaction system using hot air for heating.

[0025] Description of Reference Numerals

[0026] 1 is a heat source, 2 is an endothermic reactor, 21 is a spoiler surface, 3 is an induced draft fan, 4 is a first channel, 5 is a second channel, 6 is a third channel, 7 is a fourth channel, 8 is a fifth channel, 9 is an air door, 10 is a heat-insulating shell, 11 is an electric heating resistance wire, 12 is a vacuum pump, 13 is a heat compensation device, and 14 is an exhaust gas utilization device. DETAILED DESCRIPTION

[0027] The following is combined with Figure 1 To the attached Figure 5 The specific implementation of the embodiment of the present invention is described in detail. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.

[0028] Taking into account the low energy utilization efficiency of existing endothermic reactors, the poor utilization of volatile energy resources such as waste heat resources and wind and solar resources, as well as the complex heat transfer structure, high operating costs, and poor control effects, the present invention proposes an endothermic reaction system and control method for hot air heating.

[0029] Please see the attached Figure 1 The hot air heating endothermic reaction system of the present invention includes a heat source 1, a circulation channel, an endothermic reactor 2 connected to the heat source 1 via the circulation channel, an induced draft fan 3 disposed within the circulation channel, and a heat source outlet regulating mechanism. Each component is described below.

[0030] Heat source 1 is used to provide thermal energy. In this embodiment, the temperature of the heat source is 200-600°C. To reduce costs and save energy and protect the environment, heat source 1 can utilize clean energy or unstable resources (such as wind and solar resources). Accordingly, heat source 1 can be a heat storage body, a fuel engine, and a solid oxide battery. Among them, the fuel engine uses hydrogen as fuel, directly generates electricity through hydrogen combustion or uses the kinetic energy generated by the combustion process to drive mechanical movement or generate electricity, generating a large amount of heat and electricity during the power generation process. The heat storage body can utilize unstable resources, store energy when the unstable resources are sufficient, and then use the energy stored in the heat storage body to heat the endothermic reaction system. Unstable resources include wind and solar resources and waste heat resources. The solid-state heat storage body uses phase change materials, molten salt systems, or ceramic heat storage bodies. The ceramic heat storage body can be MgO (magnesium oxide) or Al2O3 (aluminum oxide).

[0031] By coupling heat source 1 with endothermic reactor 2, the present invention effectively utilizes clean energy and unstable resources, indirectly reducing the energy consumption of endothermic reactor 2 and improving overall thermal efficiency and economic efficiency. Heat source 1 can efficiently utilize external thermal energy, for example, by utilizing electric heat storage primarily from wind and solar energy to continuously and cost-effectively power endothermic reactor 2. This coupling of solid-state heat storage with waste heat from hydrogen fuel exhaust achieves energy complementarity and low-carbon operation, resulting in energy conservation, environmental protection, and low operating costs.

[0032] Endothermic reactor 2 is used to carry out endothermic reactions using heat energy under the action of a catalyst, such as dehydrogenation reactions and methanol cracking reactions. Dehydrogenation reactions after hydrogen storage in organic liquids include dehydrogenation of N-alkylcarbazole, hydrogenated benzyltoluene, hydrogenated bipyridine, hydrogenated N-alkylindole, dehydrogenation of 1,4-butanediol to γ-butyrolactone, dehydrogenation of propane to propylene, dehydrogenation of methanol to methyl formate, and dehydrogenation of ethanol to acetaldehyde or ethyl acetate. The energy generated by endothermic reactions is generally used to power external devices. However, the present invention not only utilizes the primary energy for powering external devices but also fully utilizes the outlet cooling energy (including low-temperature heat energy) generated simultaneously with the primary energy after the endothermic reaction, which is discharged through the air outlet and circulated within the circulation channel. The catalyst is located in the catalyst bed at a temperature of 200-450°C. Regarding the specific structure of the endothermic reactor 2, the endothermic reactor 2 includes a shell side, a flow disturbance device disposed within the shell side, and multiple finned tubes. The endothermic reactor 2 can be shaped as a cube or cylinder. The shell side provides the internal space of the endothermic reactor 2 and is connected to a circulation channel, which directly delivers heat energy to the shell side of the endothermic reactor 2. The flow disturbance device includes multiple flow disturbance surfaces 21 with apertures. The flow disturbance surfaces 21 are disposed transversely within the shell side, with the spacing between the flow disturbance surfaces 21 being 20% ​​to 80% of the inner diameter of the endothermic reactor 2. Each flow disturbance surface 21 can be formed by one or more flow disturbance rods arranged transversely or by one or more baffles arranged in a row. The flow disturbance rods can be arranged in a sequential, staggered, or spiral arrangement, and the baffles can be single-bow, double-bow, spiral, or disc-shaped. Multiple finned tubes pass through the apertures of the flow disturbance surfaces 21 and are arranged vertically within the shell side. The tubes are filled with catalyst and the reaction medium is passed through for reaction. The finned tubes are generally arranged in parallel, with the interior of the finned tube being a smooth tube, and fins are provided on the outer wall of the smooth tube. The fins may be spiral, longitudinal, or annular. In this embodiment, the fin height is 1 to 20 mm, and the fin spacing is 1 to 50 mm. In order to maintain the internal space of the endothermic reactor 2, the temperature above is consistent with the temperature below, and the fins and / or spoiler surfaces 21 of the upper finned tubes are more densely distributed than those below the endothermic reactor 2. Specifically, the finned tubes may be variable density finned tubes, and the spoiler surfaces 21 may be adjusted, such as by changing the number and spacing of spoiler rods; changing the cutting rate and spacing of the baffles, etc.

[0033] To address the large temperature differences, high heat losses, and system complexity associated with the multi-stage heat transfer in the conventional endothermic reactor 2, this application connects the heat source 1 and the endothermic reactor 2 via a circulation channel, which delivers heat energy to the endothermic reactor 2 and returns the outlet cold energy to the heat energy inlet of the endothermic reactor 2. The heat energy inlet, as used herein, refers to the portion of the circulation channel primarily used for heat energy transmission. As a result, the endothermic reactor 2 need only be connected to the circulation channel and rely solely on the medium within the circulation channel to complete heat energy transfer, eliminating the need for a separate heat-conducting medium within the endothermic reactor 2 and the need for a control device to coordinate this heat-conducting medium. This results in greater cost savings and improved thermal energy utilization efficiency. Furthermore, to improve energy utilization efficiency, if the outlet cold energy generated by the endothermic reactor 2 (including low-temperature heat energy generated simultaneously with the outlet cold energy) meets thermal energy utilization standards, this energy is preferentially transferred to the heat source 1 for reheating, thereby improving system thermal efficiency. The air within the circulation channel can be selected to be natural air, or an inert gas such as nitrogen or carbon dioxide, depending on the reaction characteristics of the endothermic reactor 2.

[0034] In terms of specific structure, the circulation channel includes at least a first channel 4, a second channel 5, and a third channel 6 that connects the first and second channels 4, 5. The first channel 4 delivers hot air to the endothermic reactor 2, and the second channel 5 delivers cold air into the first channel 4 via the third channel 6. The present invention proposes an embodiment for connecting the endothermic reactor 2 to the circulation channel. Specifically, an air outlet and an air inlet are provided on the sidewall of the endothermic reactor 2. Specifically, the air outlet and air inlet are provided on the outer wall of the shell side and connected to the interior of the shell side. The circulation channel communicates with the interior of the endothermic reactor 2 through these air outlets and air inlets. The first channel 4 connects the air inlet to the heat source 1, and the heat source inlet is provided at the first channel 4. The second channel 5 connects the air outlet to the third channel 6, and the third channel 6 connects the first and second channels 4, 5. The outlet cold energy, in the form of cold air, passes through the air outlet, the second channel 5, and the third channel 6 in sequence to enter the heat energy inlet. The heat energy, in the form of hot air, passes through the first channel 4 and the air inlet in sequence to enter the tube side. The location and number of the air outlet and air inlet vary with the structure of the circulation channel. In addition, to accelerate the flow of hot and cold air in the shell side of the endothermic reactor 2, a fan or a front system with pressure drive is used inside the endothermic reactor 2. The fan adopts a forced draft or induced draft type.

[0035] The induced draft fan 3 is arranged in the circulation channel and is started under the driving force of electricity or pressure. It generates air flow based on the principle of pressure difference, so that the outlet cold energy is transported in the form of cold air and / or the heat energy is transported in the form of hot air. Two induced draft fans 3 can be provided, with at least one induced draft fan 3 positioned within the first channel near the air inlet of the endothermic reactor 2. This effectively delivers heat energy to the shell side. As the hot air in the shell side passes through the finned tubes, heat is absorbed by the endothermic reaction within the finned tubes, thereby reducing its temperature. Simultaneously, the endothermic reaction generates outlet cooling energy. At least one induced draft fan 3, positioned within the second channel near the air outlet of the endothermic reactor 2, effectively extracts this outlet cooling energy and the cooled hot air (collectively, outlet cooling energy) from the endothermic reactor 2. The cooling energy passes through the second and third channels 5 and 6 and enters the hot air inlet of the first channel 4. This overcomes the resistance drop within the endothermic reactor 2, facilitating the extraction of outlet cooling energy from the endothermic reactor 2. It also generates return air, promoting air flow and circulation within the circulation channel. Furthermore, it reduces the temperature near the air inlet of the endothermic reactor 2, reducing component wear and extending its life. By generating a pressure differential within the circulation channel, this provides motive force for air flow, thereby driving gas movement within the circulation channel and transferring energy. In this embodiment, the temperature range of the hot air is 200-500°C, preferably 220-450°C, and optimally 230-400°C.

[0036] The heat source outlet regulating mechanism includes a damper 9, which is adjustable in opening inside the circulation channel. By changing the driving force to adjust the opening size of the damper 9, the air flow generated by the induced draft fan 3 in the circulation channel can be adjusted. In addition, when the return air of the induced draft fan 3 is not enough to cause air flow, the pressure at the second channel 5 can be changed by adjusting the damper 9, thereby causing the cold air to flow back in the third channel 6. Due to the structure of the circulation channel and the different positions of the air inlet and outlet, the damper 9 can be set at different positions, and the position setting should be mainly for the purpose of regulating air flow. Specifically, the damper 9 can be set at the intersection of the second channel 5 and the third channel 6 or the intersection of the first channel 4 and the third channel 6. The structure of the damper 9 can adopt a butterfly valve or a gate valve; the power source of the damper 9 is air drive or electric drive.

[0037] The present invention regulates the gas flow in the circulation channel through the induced draft fan 3 and the heat source outlet regulating mechanism, and accordingly transfers energy in the form of wind, providing heat energy to the endothermic reactor 2 through hot air circulation. No other heat exchange medium is required in the endothermic reactor 2, thereby simplifying the structure of the endothermic reactor 2. While reducing complexity, the hot air is fully in contact with the fin tubes, reducing the heat transfer temperature difference. In addition, hot air is only required as a heat exchange medium once, reducing the number of heat transfers and increasing the integration of the system. Through wind circulation, heat energy flows continuously and continuously to provide heat for the endothermic reactor 2. While simplifying the structure, heat loss is greatly reduced. At the same time, clean energy is used as the main source of heat source 1, which improves the efficiency of energy utilization.

[0038] To further minimize heat loss, the present invention further includes an insulating housing 10 within the endothermic reaction system. This housing 10 is positioned outside the endothermic reactor 2, with a vacuum environment or heat-dissipating thermal resistance material between the housing 10 and the endothermic reactor 2. Examples of heat-dissipating thermal resistance materials include aluminum silicate, rock wool, and perlite. The housing 10 can be constructed of steel.

[0039] To improve the structure and provide the endothermic reaction system with more functionality, the present invention further provides a heat compensation device 13 and / or an exhaust gas utilization device 14. The heat compensation device 13 is connected to the endothermic reactor 2 via a circulation channel to supplement heat energy, ensuring the stable heat energy provided by the heat source 1 and allowing the endothermic reaction to proceed smoothly. To effectively utilize the endothermic reaction, an exhaust gas utilization device 14 is provided. The exhaust gas utilization device 14 is connected to the endothermic reactor 2 and is used to collect and utilize the gases generated after the reaction in the endothermic reactor 2. Accordingly, a solid or liquid device can be provided to collect and utilize the substances generated after the endothermic reaction.

[0040] Please see the attached Figure 2 For the above-mentioned endothermic reaction system with hot air heating, the present invention also proposes a control method for the endothermic reaction system with hot air heating for the purpose of precise control, including the following steps:

[0041] S100: Monitor the temperature change of the hot air near the induced draft fan 3. Excessively high or low hot air temperature can easily damage nearby equipment and hinder the reaction within the endothermic reactor 2, such as by deactivating the catalyst and preventing the endothermic reaction. Therefore, this step is used to determine the temperature of the hot air. When measuring temperature, it is best to monitor the temperature change of the hot air near the induced draft fan 3 in the first channel 4.

[0042] S200. In response to the temperature change information, the driving force of the induced draft fan 3 and / or the heat source outlet regulating mechanism is changed so that the reaction temperature fluctuation and / or reaction load fluctuation of the endothermic reactor 2 are within a preset range. The preset range is set with the goal of ensuring that the endothermic reaction can meet the energy demand of the external equipment. As can be seen from the above description, the induced draft fan 3 is used to generate air flow. The faster the speed of the induced draft fan 3, the better the air flow effect and the faster the wind circulation. At this time, the intermediate reaction stage of the endothermic reactor 2 requires a large amount of heat and the generated energy is discharged to avoid affecting the reaction; on the contrary, the speed of the induced draft fan 3 is reduced to limit the reaction or post-reaction stage and save energy. Similarly, the heat source outlet regulating mechanism changes the pressure in the second channel 5 by adjusting the opening of the damper 9, thereby adjusting the size of the reflux or generating reflux, and regulating the wind circulation in the circulation channel.

[0043] Specifically, step S200 has the following process.

[0044] S210 , preset a hot air limit value, and compare the preset hot air limit value with the real-time hot air temperature near the induced draft fan 3 based on the temperature change information.

[0045] S220. With the goal of achieving an endothermic reaction, ensure the reaction temperature and reaction load conditions within the endothermic reactor 2. When the hot air temperature is higher than the hot air limit, change the driving force to reduce the opening of the damper 9 to increase the circulation volume, while reducing the driving force of the induced draft fan 3 to reduce the air intake. When the hot air temperature is lower than the hot air limit, increase the opening of the damper 9 to reduce the circulation volume, while increasing the driving force of the induced draft fan 3 to increase the air intake. The smaller the opening of the damper 9, the greater the return air volume and the greater the air volume in the circulation channel. In this embodiment, the reaction temperature fluctuation of the endothermic reactor 2 is ≤±10°C, and the reaction load fluctuation adjustment range is 30% to 110%. The return air volume is 0.1 to 10 times the circulation volume.

[0046] In order to effectively utilize unstable resources and significantly reduce electricity costs, the present invention also proposes a corresponding dynamic adjustment process. The control process of the endothermic reaction system with hot air heating using stable thermal energy as the heat source adopts steps S100 and S200, but the control process inevitably uses electric energy to drive the induced draft fan 3 or the heat source outlet regulating mechanism, so the power consumption is relatively large. However, when the heat source is an unstable resource, the electricity price is green electricity. Compared with the general electricity price of about 0.5 to 1.0 yuan, the price of green electricity is only 0.1 to 0.4 yuan. The use of a heat storage body to utilize unstable resources, through the low-cost electricity of the unstable resource to heat the heat storage body, convert the electrical energy into thermal energy and store it, and release the thermal energy to the endothermic reactor 2 when the electricity price is high. Therefore, the following control process steps for opening and closing the endothermic reaction system with hot air heating should be preset before step S100.

[0047] Specifically, when heat source 1 is a heat storage body and is powered by non-stable resources, the following control process occurs before monitoring the temperature change information of the hot air near the induced draft fan 3. First, the availability of non-stable resources is checked. The more sufficient the non-stable resources, the lower the electricity cost and the better the electric-to-heat conversion effect. Non-stable resources here include waste heat resources, wind and solar resources, etc., with wind and solar resources being more effective. Subsequently, if it is detected that the non-stable resources are insufficient, the electricity cost is high, and heat stored in the heat storage body is needed for heating. The circulation channel is opened, and the induced draft fan 3 and / or the heat source outlet regulating mechanism are activated to regulate the circulation process. If it is detected that the non-stable resources are sufficient, the electricity cost is low, and the heat storage body is heated to a preset temperature in a low-cost manner to store the heat. At this time, whether to open the circulation channel is determined based on the energy demand of the external device. When the external device does not require energy, or in similar situations, the circulation channel is closed to prevent excessive electricity consumption of the endothermic reaction system. It is then opened the next time the non-stable resources are sufficient, that is, when the electricity cost is low.

[0048] The above temperature change information or control instructions can be stored in the PLC or DCS to monitor the temperature of the reactor and upstream heat source in real time to achieve a complete control process.

[0049] In order to more completely describe the above content, the present invention proposes three embodiments of an endothermic reaction system for hot air heating and a control method.

[0050] Please see the attached Figure 3 In the first embodiment, a heat source 1, an endothermic reactor 2, an induced draft fan 3, a heat source outlet regulating mechanism, and an insulating shell 10 are included. The heat storage body utilizes wind and solar resources as the heat source 1, supplemented by an electric heating resistor 11 for heat energy storage. In addition to the first channel 4, the second channel 5, and the third channel 6, the circulation pipeline also includes a fourth channel 7. The fourth channel 7 is located at the junction of the second channel 5 and the third channel 6, and flows back to the heat storage body. The endothermic reactor 2 is provided with one air inlet and one air outlet. Two induced draft fans 3 are provided, one in the first channel 4 and the other in the second channel 5. The damper 9 of the heat source outlet regulating mechanism is located at the intersection of the first channel 4 and the third channel 6, and can completely close the first channel 4, blocking the heat energy supply between the heat storage body and the endothermic reactor 2. The insulating shell 10 is made of aluminum silicate fiber, and the outer layer is an alloy aluminum skin. In the endothermic reactor 2, the finned tube is a spiral finned tube, and the spoiler surface 21 is provided with a baffle.

[0051] In the aforementioned endothermic reaction system powered by hot air, driven by the induced draft fan 3 and the heat source outlet regulating mechanism, heat energy flows from the heat storage body into the shell side in the form of hot air through the first channel 4. The outlet cold energy (including heat energy at a temperature lower than that of the heat storage body) flows back to the heat storage body in the form of cold air through the second channel 5 for utilization, and then enters the heat energy inlet of the first channel 4 via the third channel 6. A control method for the aforementioned endothermic reaction system includes the following process: A standard can be set based on the properties of the endothermic reaction performed by the endothermic reaction system powered by hot air and historical endothermic data, thereby setting the preset temperature of the heat storage body to 300-800°C. During periods of high wind and solar power generation and low electricity prices, the endothermic reaction system is inoperative, and only the resistance wire is used to heat the heat storage body to the preset temperature. The passages between the heat source 1 and the endothermic reactor 2 are closed, and other regulating mechanisms within the endothermic reaction system are also disabled. In this embodiment, the damper 9 can be moved downward to cut off air flow in the first channel 4. During periods of low wind and solar power generation and high electricity prices, the endothermic reaction system operates and uses the heat storage body for energy. The induced draft fan 3 is started to heat the endothermic reactor 2 through hot air circulation, and the intake air temperature is adjusted by the damper 9 to continuously supply heat to the endothermic reactor 2. During operation, when the temperature of the hot air at the induced draft fan 3 in the solid-state heat storage body or the first channel 4 is higher than the hot air limit, the circulation volume is increased by adjusting the damper 9, and the air intake volume is reduced by adjusting the induced draft fan 3. When the temperature of the hot air at the induced draft fan 3 in the solid-state heat storage body or the first channel 4 is lower than the hot air limit, the circulation volume is reduced by adjusting the damper 9, and the air intake volume is increased by adjusting the induced draft fan 3.

[0052] Please see the attached Figure 4 Embodiment 2, in the second embodiment, includes a heat source 1, an endothermic reactor 2, an induced draft fan 3, a heat source outlet regulating mechanism, an insulation shell 10, and a vacuum pump 12. Among them, the heat source 1 is a hydrogen fuel engine. In addition to the first channel 4, the second channel 5, and the third channel 6, the circulation pipeline also has a fifth channel 8 located at the connection between the second channel 5 and the third channel 6, and the damper 9 is located in the fifth channel 8. The extension direction of the fifth channel 8 can be horizontal or vertical. The insulation shell 10 is a metal shell, and the space between the shell and the endothermic reactor 2 is sucked into a vacuum state by the vacuum pump 12. The hot air limit at the exhaust of the hydrogen fuel engine is 300~600℃. The exhaust gas of the engine is introduced into the reactor by the induced draft fan 3 in the first channel 4, and the exhaust gas flow is controlled. The gas in the endothermic reactor 2 is sucked by the induced draft fan 3 in the second channel 5, and the hot air circulation amount is adjusted by the heat source outlet regulating mechanism. The finned tubes in the endothermic reactor 2 are variable density finned tubes, with sparse fins at the bottom to reduce heat transfer and dense fins at the top to enhance heat transfer and ensure uniform temperature. The shell side is a spiral plate structure, with multiple spoiler surfaces 21 having broken line cross sections.

[0053] In the aforementioned endothermic reaction system using hot air heating, driven by the induced draft fan 3 and the heat source outlet regulating mechanism, heat energy flows from the hydrogen fuel engine into the shell side in the form of hot air through the first channel 4. The outlet cold energy (including heat energy with a temperature lower than that of the heat storage body) flows back to the heat energy inlet in the first channel 4 in the form of cold air through the second channel 5 and the third channel 6, respectively. During operation, when the temperature of the hot air at the hydrogen fuel engine or the induced draft fan 3 in the first channel 4 exceeds the hot air limit, the circulation volume is increased by adjusting the damper 9, and the air intake is reduced by adjusting the induced draft fan 3. When the temperature of the hot air at the hydrogen fuel engine or the induced draft fan 3 in the first channel 4 falls below the hot air limit, the circulation volume is reduced by adjusting the damper 9, and the air intake is increased by adjusting the induced draft fan 3. The hot air limit is 300-600°C.

[0054] Please see the attached Figure 5 In the third embodiment, the heat source 1, the endothermic reactor 2, the induced draft fan 3, the heat source outlet regulating mechanism, the heat-insulating shell 10, the heat compensation device 13, and the tail gas utilization device 14 are included. Among them, the heat source 1 is a solid oxide battery. The heat compensation device 13 is an electric heater, which is arranged in the first circulation channel. The tail gas utilization device 14 utilizes hydrogen and recovers it to the heat source 1. In addition to the first channel 4, the second channel 5, and the third channel 6, the circulation pipeline also has a fifth channel 8 located at the connection between the second channel 5 and the third channel 6, and the damper 9 is located in the fifth channel 8. The heat-insulating shell 10 is a metal shell, and the space between the shell and the endothermic reactor 2 is filled with perlite, and the inside of the shell is covered with an insulation board. The finned tubes of the endothermic reactor 2 are corrugated fins, and the shell side is a spoiler rod structure, and the spoiler rods are arranged crosswise with the finned tubes. The spoiler rods at the bottom of the shell side are sparsely arranged, and the spoiler rods at the top are densely arranged, so as to keep the temperature of the reactor consistent. The exhaust gas from the solid oxide cell is drawn into the endothermic reactor via the induced draft fan 3 within the first channel 4. The exhaust gas flow is controlled, and heat compensation is performed by an electric heater. The exhaust gas within the reactor is drawn by the induced draft fan 3 within the second channel 5, and the hot air circulation rate is regulated by the damper 9 of the hot air outlet regulating mechanism. The dehydrogenation reaction within the endothermic reactor 2 produces hydrogen that enters the solid oxide cell for reaction, and the excess electricity generated by the reaction is continuously output.

[0055] In the aforementioned endothermic reaction system using hot air heating, driven by the induced draft fan 3 and the heat source outlet regulating mechanism, heat energy flows from the solid oxide battery to the shell side in the form of hot air through the first channel 4. The outlet cold energy (including heat energy with a temperature lower than that of the heat storage body) flows back to the heat energy inlet in the first channel 4 in the form of cold air, sequentially through the second channel 5 and the third channel 6. During operation, when the temperature of the hot air at the solid oxide battery or the induced draft fan 3 in the first channel 4 exceeds the hot air limit, the circulation volume is increased by adjusting the damper 9, and the air intake is reduced by adjusting the induced draft fan 3. When the temperature of the hot air at the solid oxide battery or the induced draft fan 3 in the first channel 4 falls below the hot air limit, the circulation volume is reduced by adjusting the damper 9, and the air intake is increased by adjusting the induced draft fan 3. The hot air limit is 800-1000°C.

[0056] From the above description, it can be seen that the present invention has at least the following three advantages:

[0057] 1) Using low-cost heat sources such as heat storage or industrial waste heat, fuel engines fueled by clean energy such as hydrogen, and solid oxide batteries that react with hydrogen to generate electricity to continuously power the endothermic reactor, achieving efficient utilization of thermal energy and low-carbon operation of the system;

[0058] 2) Heat exchange is achieved in the form of wind generated by air flow, which increases heat exchange efficiency. The structure of the finned tubes and the spoiler surface (specifically, the arrangement of the spoiler rods and baffles on the spoiler surface and the relationship between the spoiler surfaces) increases system turbulence and improves heat transfer efficiency. The insulation shell is used to enhance insulation and reduce system heat loss. At the same time, system redundancy is reduced, system integration is increased, system operating costs are reduced, and energy utilization efficiency is increased.

[0059] 3) The control method uses the hot air temperature in the first channel as the standard to control the induced draft fan and the damper to ensure the reaction temperature and reaction pressure in the endothermic reactor; based on whether the non-stable resources (wind and solar resources) are sufficient, it is determined whether the endothermic reaction system with hot air heating is working; a control device such as a PLC or DCS is used to couple the heat source with the endothermic reactor, regulate the fan and control valves, and intelligently adjust the energy efficiency and system stability, thereby improving the overall thermal efficiency and intelligence, and at the same time reducing the electricity cost.

[0060] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0061] The above are merely embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A hot air heating endothermic reaction system, characterized in that: include: Heat source, used to provide thermal energy; An endothermic reactor, used to carry out endothermic reactions to provide energy for external equipment and generate export cold energy; a circulation channel connecting the heat source and the endothermic reactor, for delivering the heat energy to the endothermic reactor and delivering the outlet cold energy back to the heat energy inlet of the endothermic reactor; an induced draft fan, disposed in the circulation channel, for generating air flow so that the outlet cold energy is transported in the form of cold air and / or the outlet heat energy is transported in the form of hot air; as well as The heat source outlet regulating mechanism includes a damper, the damper opening of which is adjustable and arranged inside the circulation channel to regulate the air flow. The side wall of the endothermic reactor is provided with an air outlet and an air inlet, which are connected to the interior of the endothermic reactor; at least one induced draft fan is close to the air outlet, and at least one induced draft fan is close to the air inlet. The circulation channel includes a first channel, a second channel, and a third channel that connects the first channel and the second channel. The first channel sends the hot air to the endothermic reactor, and the second channel sends the cold air to the first channel via the third channel. The damper is arranged at the intersection of the second channel and the third channel; or, the damper is arranged at the intersection of the first channel and the third channel.

2. The endothermic reaction system with hot air heating according to claim 1, characterized in that: The heat source is one of a heat storage body, a fuel engine and a solid oxide battery, The temperature of the heat source is 200-600°C.

3. The endothermic reaction system with hot air heating according to claim 1, characterized in that: The endothermic reaction system further includes a heat-insulating shell, which is arranged outside the endothermic reactor, and a vacuum environment or heat-dissipating thermal resistance material is provided between the heat-insulating shell and the endothermic reactor.

4. The endothermic reaction system with hot air heating according to claim 1, characterized in that: The endothermic reactor is in the shape of a cube or a cylinder. The catalyst bed temperature in the endothermic reaction is 200-450°C. The endothermic reaction is a dehydrogenation reaction of an organic liquid after hydrogen storage, including hydrogenation of N-alkylcarbazole dehydrogenation, hydrogenation of benzyltoluene dehydrogenation, hydrogenation of bipyridine dehydrogenation, hydrogenation of N-alkylindole dehydrogenation, dehydrogenation of 1,4-butanediol to γ-butyrolactone, dehydrogenation of propane to propylene, dehydrogenation of methanol to methyl formate, and dehydrogenation of ethanol to acetaldehyde or ethyl acetate.

5. The endothermic reaction system with hot air heating according to claim 1, characterized in that: The endothermic reactor comprises: a shell side, for providing an inner space of the endothermic reactor, and the shell side is in communication with the circulation channel; A flow-disturbing device, comprising a plurality of flow-disturbing surfaces with pores, wherein the flow-disturbing surfaces are laterally arranged in the shell side; and A plurality of fin tubes pass through the pores of the spoiler surface and are vertically arranged inside the shell side. The reaction is carried out inside the fin tubes.

6. The endothermic reaction system with hot air heating according to claim 5, characterized in that: Compared with the lower part of the endothermic reactor, the fins and / or the spoiler surfaces of the upper finned tubes are more densely distributed.

7. The endothermic reaction system with hot air heating according to claim 1, characterized in that: The endothermic reaction system further comprises a heat compensation device and / or an exhaust gas utilization device; The heat compensation device is connected to the endothermic reactor through the circulation channel to supplement the heat energy; The tail gas utilization device is connected to the endothermic reactor and is used to collect and utilize the gas generated after the reaction in the endothermic reactor.

8. A control method for a hot air heating endothermic reaction system according to any one of claims 1 to 7, characterized in that: The steps include: Monitoring temperature change information of the hot air near the induced draft fan; and In response to the temperature change information, the driving force of the induced draft fan and / or the heat source outlet regulating mechanism is changed so that the reaction temperature fluctuation and / or reaction load fluctuation of the endothermic reactor are within a preset range, so that the endothermic reaction can provide energy for the external device.

9. The control method according to claim 8, characterized in that: The step of changing the driving force of the induced draft fan and / or the heat source outlet regulating mechanism in response to the temperature change information further includes the following steps: Preset hot air limit; When the temperature of the hot air is higher than the hot air limit, the driving force is changed to reduce the air door opening and the driving force of the induced draft fan is reduced; and When the temperature of the hot air is lower than the hot air limit, the driving force is changed to increase the air door opening, and the driving force of the induced draft fan is increased at the same time.

10. The control method according to claim 8, characterized in that: When the heat source is a heat storage body and the heat storage body is powered by an unstable resource, the following control process is performed before monitoring the temperature change information of the hot air near the induced draft fan: When it is detected that the unstable resource is insufficient, the heat storage body is used to supply heat, the circulation channel is opened, and the induced draft fan and / or the heat source outlet regulating mechanism are started; When it is detected that the unstable resource is sufficient, the unstable resource is stored in the heat storage body, the heat storage body is heated to a preset temperature, and whether to open the circulation channel is determined according to the energy demand of the external device.

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