Photo-thermal supply system and method for LOHC dehydrogenation

Abstract

The invention discloses a photo-thermal supply system and method for LOHC dehydrogenation, and belongs to a solar energy application and hydrogen energy storage and transportation technology, the system comprises an LOHC dehydrogenation reactor and an HTF circulating pipeline, the HTF circulating pipeline passes through the LOHC dehydrogenation reactor and a parabolic trough heat collector, and a PCM energy storage module; a high-temperature pump is installed on the HTF circulating pipeline and used for driving a heat exchange medium to conduct heat transfer between the parabolic trough heat collector and the LOHC dehydrogenation reactor and between the parabolic trough heat collector and the PCM energy storage module through the HTF circulating pipeline. The phase change material with an optimized formula is integrated in the PCM energy storage module, the defect that heat supply is unstable due to the intermittent characteristic of a solar parabolic trough heat collector can be overcome by matching with an HTF circulating pipeline, and the phase change material releases latent heat to support continuous operation of the LOHC dehydrogenation reactor at night or in the period of insufficient sunlight. By switching the flowing direction of the heat exchange medium in the HTF circulating pipeline, the stability and continuity of heat supply can be guaranteed in the daytime and at night or when sunlight is insufficient.

Description

Technical Field

[0001] This invention relates to a solar energy application and hydrogen energy storage and transportation technology. More specifically, this invention relates to a photothermal supply system and method for LOHC dehydrogenation. Background Technology

[0002] Liquid organic hydrogen carrier (LOHC) dehydrogenation is an endothermic reaction, typically requiring an external heat source to provide temperatures of 250-280°C to drive the reaction. Traditionally, this high-temperature heat energy is primarily provided by the combustion of fossil fuels, but this method suffers from significant problems such as high energy consumption, high operating costs, and environmental pollution, especially given the current global push for clean energy and carbon emission reduction. In contrast, solar energy, as a clean and renewable energy source, offers significant environmental and economic advantages. Parabolic trough solar thermal power generation technology, in particular, can generate high-temperature heat energy up to 400°C by focusing sunlight to heat the heat transfer fluid (HTF). However, the intermittent nature of solar energy (such as day-night cycles and weather variations) limits its direct application in industrial processes requiring continuous operation, especially in scenarios like LOHC dehydrogenation where high temperature stability is crucial. Therefore, although parabolic trough solar thermal energy has made some progress in the field of clean energy power generation, it still cannot meet the specific needs of LOHC dehydrogenation. Therefore, it is necessary to conduct further research and improvement on the application technology of solar energy in LOHC dehydrogenation. Summary of the Invention

[0003] One of the objectives of this invention is to address the aforementioned shortcomings by providing a photothermal supply system and method for LOHC dehydrogenation. This aims to solve the technical problems in the prior art, such as high energy consumption and high operating costs associated with relying on fossil fuel combustion for heating LOHC dehydrogenation, and the impact of the intermittent nature of solar energy on the stability of LOHC dehydrogenation operating temperature.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: This invention provides a photothermal supply system for LOHC dehydrogenation, comprising an LOHC dehydrogenation reactor and an HTF circulation pipeline, wherein the HTF circulation pipeline passes through the LOHC dehydrogenation reactor, a parabolic trough collector, and a PCM energy storage module; a high-temperature pump is installed on the HTF circulation pipeline, which drives the heat exchange medium to transfer heat between the parabolic trough collector, the LOHC dehydrogenation reactor, and the PCM energy storage module through the HTF circulation pipeline; the PCM energy storage module is filled with a phase change material, the phase change material comprising, by weight... The composition includes 90-100 parts sodium nitrate, 2-6 parts lithium nitrate, and 0.5-2 parts magnesium oxide. The PCM energy storage module has an internal heat exchange tube connected to the HTF circulation pipeline, and the phase change material is wrapped around the heat exchange tube. The parabolic trough collector has an internal receiving tube located at the heat collection focal point and connected to the HTF circulation pipeline. The LOHC dehydrogenation reactor has a shell-and-tube heat exchanger, and the wall of the HTF circulation pipeline is in contact with the shell-and-tube heat exchanger.

[0005] As a preferred further technical solution, the LOHC dehydrogenation reactor, the parabolic trough collector, and the PCM energy storage module are all installed on a skid-mounted platform.

[0006] A further technical solution is as follows: a flow meter and a pressure sensor are installed on the HTF circulation pipeline; a temperature sensor is installed on the shell-and-tube heat exchanger of the LOHC dehydrogenation reactor; a temperature sensor is also installed on the phase change material contact point of the PCM energy storage module; a three-way reversing valve is installed on the HTF circulation pipeline, which is used to enable the high-temperature pump to drive the heat exchange medium to flow through any one or more of the following: the parabolic trough collector and the LOHC dehydrogenation reactor, the parabolic trough collector and the PCM energy storage module, and the PCM energy storage module and the LOHC dehydrogenation reactor; the temperature sensor, flow meter, pressure sensor, high-temperature pump, and three-way reversing valve are all connected to a control module; the control module is used to control the output power of the high-temperature pump and the reversing state of the three-way reversing valve according to the current temperature of the shell-and-tube heat exchanger of the LOHC dehydrogenation reactor.

[0007] Another aspect of the present invention provides a photothermal supply method for LOHC dehydrogenation, the method using the above-described system and comprising the following steps: Step A: The parabolic trough collector heats the heat exchange medium in the receiving tube to above 350°C by reflecting sunlight. The high-temperature pump drives the heat exchange medium to flow through the shell-and-tube heat exchanger on the LOHC dehydrogenation reactor via the HTF circulation pipeline for heat exchange, maintaining the dehydrogenation temperature at 250-280°C.

[0008] Step B: The parabolic trough collector heats the heat exchange medium in the receiving tube to above 350°C by reflecting sunlight. The high-temperature pump drives the heat exchange medium to flow through the heat exchange tube of the PCM energy storage module via the HTF circulation pipe, causing the phase change material to change from solid to liquid and store thermal energy.

[0009] Step C: The high-temperature pump drives the heat exchange medium to flow through the HTF circulation pipeline through the heat exchange tubes of the PCM energy storage module and the shell-and-tube heat exchanger on the LOHC dehydrogenation reactor to exchange heat and maintain the dehydrogenation temperature at 250-280°C.

[0010] As a preferred further technical solution, the high-temperature pump drives the heat exchange medium to flow through the parabolic trough collector and the LOHC dehydrogenation reactor, and through the parabolic trough collector and the PCM energy storage module. The PCM energy storage module and the LOHC dehydrogenation reactor are both connected to the corresponding parts by controlling the state of the three-way reversing valve through the control module.

[0011] A further technical solution is as follows: the control module collects the temperature of the shell-and-tube heat exchanger of the current LOHC dehydrogenation reactor through a temperature sensor, collects the flow rate of the heat exchange medium in the current HTF circulation pipeline through a flow meter, and collects the pressure of the heat exchange medium in the current HTF circulation pipeline through a pressure sensor, thereby adjusting the output power of the high-temperature pump and the connection status of the three-way reversing valve.

[0012] Compared with the prior art, one of the beneficial effects of the present invention is that by using an optimized formula of phase change material integrated into the PCM energy storage module, and in conjunction with the HTF circulation pipe, the defect of unstable heating caused by the intermittent characteristics of the solar parabolic trough collector can be made up for. At night or during periods of insufficient sunlight, the latent heat released by the phase change material supports the continuous operation of the LOHC dehydrogenation reactor. By switching the flow direction of the heat exchange medium in the HTF circulation pipe, the stability and continuity of heating can be guaranteed both during the day and at night / when sunlight is insufficient. Attached Figure Description

[0013] Figure 1 This is a schematic block diagram illustrating a system structure of an embodiment of the present invention. Detailed Implementation

[0014] The invention will now be further described with reference to the accompanying drawings.

[0015] Solar energy, as a clean and renewable energy source, has significant environmental and economic advantages. As mentioned in the background section of this invention, parabolic trough solar thermal power generation technology can generate high-temperature thermal energy up to 400°C by focusing sunlight and heating a heat transfer fluid (HTF).

[0016] A skid-mounted concentrated solar power (CSP) unit is a modular device that integrates solar energy collection, heat conversion, and power generation, and features a skid-mounted design. This design allows the entire system to be easily transported, installed, and moved, making it ideal for use in different sites or environments.

[0017] Based on the above, this invention provides a photothermal supply system for LOHC dehydrogenation. (Reference) Figure 1 As shown, in this embodiment, the system includes a LOHC dehydrogenation reactor and an HTF circulation pipeline. The HTF circulation pipeline contains a heat exchange medium, which can be driven to flow in the circulation pipeline to achieve heat exchange. Therefore, in terms of pipeline arrangement, the HTF circulation pipeline passes through the LOHC dehydrogenation reactor, the parabolic trough collector, and the PCM energy storage module. At the same time, in order to facilitate the flow of the heat exchange medium, a high-temperature pump can be installed on the aforementioned HTF circulation pipeline. As mentioned above, the high-temperature pump can drive the heat exchange medium to transfer heat between the parabolic trough collector, the LOHC dehydrogenation reactor, and the PCM energy storage module through the HTF circulation pipeline.

[0018] More importantly, the aforementioned PCM energy storage module is filled with a phase change material (PCM), which achieves thermal energy storage through the solid-liquid change of the PCM. The PCM's formulation consists of 90-100 parts by weight of sodium nitrate, 2-6 parts of lithium nitrate, and 0.5-2 parts of magnesium oxide. Heat exchange tubes are installed inside the PCM module and connected to the HTF circulation pipeline. The PCM is further encased in the aforementioned PCM. The PCM has a melting point of approximately 300°C and a latent heat of approximately 170 kJ / kg, and is stored in a high-temperature resistant and corrosion-resistant stainless steel container.

[0019] The aforementioned phase change material was prepared using the following method: Step 1: Raw material preparation: Weigh out 90-100 parts by weight of sodium nitrate (NaNO3, purity ≥99%), 2-6 parts by weight of lithium nitrate (LiNO3, purity ≥99%), and 0.5-2 parts by weight of magnesium oxide (MgO, particle size ≤50 nm, purity ≥99%). Place all raw materials in a vacuum drying oven and dry at 80-100℃ for 2-4 hours to remove moisture and impurities, ensuring that the moisture content of the raw materials is ≤0.1%.

[0020] Step 2, Preliminary Mixing: Place the dried sodium nitrate and lithium nitrate in a high-temperature resistant stainless steel container or quartz crucible, and stir with a mechanical stirrer at 200-300 rpm for 10-15 minutes at room temperature to achieve preliminary uniform mixing. Then, add magnesium oxide in batches (1 / 3 of the total amount each time), and continue stirring for 20-30 minutes to prevent magnesium oxide from agglomerating and ensure that it is uniformly dispersed as a stabilizer.

[0021] Step 3, Melting Treatment: Transfer the mixture to an electric furnace or muffle furnace and gradually heat it to 350-400℃ (approximately 50-100℃ above the melting point of the mixture) under a nitrogen protective atmosphere (nitrogen flow rate 0.5-1 L / min to prevent oxidation), controlling the heating rate at 5-10℃ / min. After reaching the target temperature, maintain the temperature for 1-2 hours, continuously stirring at 500-800 rpm to promote the incorporation of LiNO3 into the NaNO3 matrix to form a eutectic structure, while MgO acts as a nucleating agent to suppress supercooling.

[0022] Step 4, Degassing and Purification: While in the molten state, apply a vacuum (vacuum degree ≤ 0.01 MPa) for 15-30 minutes to remove air bubbles and volatile impurities. Then, allow to stand for 10-15 minutes to allow any undissolved particles to settle, and filter the molten liquid through a filter screen (pore size ≤ 100 μm) to improve material purity.

[0023] Step 5, Cooling and Shaping: Slowly cool the molten mixture to room temperature at a rate of 1-2°C / min to avoid thermal stress and crystal defects. During cooling, casting can be performed using molds to form block or granular phase change material. The final product is then crushed into particles with a diameter of 1-5 mm using a pulverizer, facilitating filling into the stainless steel container of the PCM energy storage module.

[0024] The phase change material prepared by this method has a melting point of approximately 300℃, a latent heat of approximately 170 kJ / kg, and good thermal stability, capable of withstanding cyclic use up to 450℃. Differential scanning calorimetry (DSC) testing verified that its phase change temperature fluctuation is ≤±2℃, and its cyclic stability after 500 charge-discharge cycles results in a latent heat decay of ≤5%. For optimization, the LiNO3 ratio can be adjusted to fine-tune the melting point, or the MgO content can be increased to enhance corrosion resistance, depending on the specific application.

[0025] The parabolic trough collector has a receiving tube inside, which is located at the heat collection focus of the parabolic trough collector and is connected to the HTF circulation pipeline; the LOHC dehydrogenation reactor has a shell-and-tube heat exchanger, and the tube wall of the HTF circulation pipeline is in contact with the shell-and-tube heat exchanger.

[0026] As mentioned above, to facilitate the transportation, installation, and relocation of the system and make it suitable for use in different sites or environments, this embodiment can draw on the skid-mounted platform of current skid-mounted solar thermal power generation devices, and install the aforementioned LOHC dehydrogenation reactor, parabolic trough collector, and PCM energy storage module on the skid-mounted platform.

[0027] Furthermore, in the above embodiments, for ease of control, a control module based on a programmable logic controller (PLC) is introduced into the system. The control module collects various parameters to control the connection status of the high-temperature valve and the three-way directional valve. Based on the aforementioned concept, and building upon the structure shown in the above embodiments, a flow meter and pressure sensor are installed on the HTF circulation pipeline, and a temperature sensor is installed on the shell-and-tube heat exchanger of the LOHC dehydrogenation reactor; a temperature sensor is also installed at the phase change material contact point of the PCM energy storage module; the acquisition ends of the aforementioned temperature sensor, flow meter, and pressure sensor are all in contact with the required acquisition locations in the system. Then, the aforementioned three-way directional valve is installed on the HTF circulation pipeline. Under normal conditions, both ends of the three-way directional valve are connected, thereby achieving three forms of connection: the high-temperature pump drives the heat exchange medium to flow through the parabolic trough collector and the LOHC dehydrogenation reactor, through the parabolic trough collector and the PCM energy storage module, and through the PCM energy storage module and the LOHC dehydrogenation reactor. This allows the heat exchange medium to flow within the pipeline and complete heat exchange. Then, the temperature sensor, flow meter, pressure sensor, high-temperature pump, and three-way reversing valve are all connected to the control module. The control module controls the output power of the high-temperature pump and the switching state of the three-way reversing valve based on the current temperature of the shell-and-tube heat exchanger in the LOHC dehydrogenation reactor. Simultaneously, the output power of the high-temperature pump and the switching state of the three-way reversing valve can also be controlled by the flow rate, velocity, and pressure of the heat exchange medium in the current HTF circulation pipeline, as well as the solid-liquid state (low-temperature solid, high-temperature liquid) of the phase change material in the PCM energy storage module.

[0028] Based on the above system, another embodiment of the present invention is a photothermal supply method for LOHC dehydrogenation. The method uses the above system and is performed according to the above steps: Under normal conditions (when there is sufficient solar energy during the day), the parabolic trough collector heats the heat exchange medium in the receiving tube to above 350°C by reflecting sunlight. The high-temperature pump drives the heat exchange medium to flow through the shell-and-tube heat exchanger on the LOHC dehydrogenation reactor via the HTF circulation pipeline for heat exchange, so as to maintain the dehydrogenation temperature at 250-280°C.

[0029] Meanwhile, under normal conditions, when the heat required for the operation of the LOHC dehydrogenation reactor is sufficient, based on the same principle mentioned above, the parabolic trough collector heats the heat exchange medium in the receiving tube to above 350°C by reflecting sunlight. The high-temperature pump drives the heat exchange medium to flow through the heat exchange tube of the PCM energy storage module via the HTF circulation pipe, causing the phase change material to change from solid to liquid and store thermal energy. In this step, by switching the connection state of the three-way reversing valve, solar energy heating and thermal energy storage can be carried out simultaneously (short-term alternation, close to synchronization).

[0030] Specifically, the control module uses a temperature sensor to collect the temperature of the shell-and-tube heat exchanger in the LOHC dehydrogenation reactor, a flow meter to collect the flow rate of the heat exchange medium in the HTF circulation pipeline, and a pressure sensor to collect the pressure of the heat exchange medium in the HTF circulation pipeline. This allows for the adjustment of the high-temperature pump's output power and the connection status of the three-way reversing valve, thereby controlling the flow rate and direction of the heat exchange medium. Specifically, regarding the flow direction of the heat exchange medium, the high-temperature pump drives the medium to flow through the parabolic trough collector and the LOHC dehydrogenation reactor, through the parabolic trough collector and the PCM energy storage module, and through the PCM energy storage module and the LOHC dehydrogenation reactor. The control module controls the state of the three-way reversing valve to connect the HTF circulation pipeline to the corresponding sections.

[0031] When solar energy is insufficient for heating (at night or on cloudy days), a high-temperature pump drives the heat exchange medium through the HTF circulation pipeline to flow through the heat exchange tubes of the PCM energy storage module and the shell-and-tube heat exchanger on the LOHC dehydrogenation reactor to exchange heat and maintain the dehydrogenation temperature at 250-280℃.

[0032] In this embodiment, an optimized phase change material formulation is proposed, which not only meets the 250-280°C temperature requirement for LOHC dehydrogenation but also significantly improves corrosion resistance and fire resistance through the addition of auxiliary materials. This invention achieves comprehensive optimization of melting point control, corrosion inhibition, and enhanced stability through the synergistic effect of a low proportion of LiNO3 (4%) and MgO (1%). This formulation improves system durability while maintaining low cost, overcoming the limitations of traditional PCM applications. It solves the combined challenges of intermittent solar energy, PCM corrosion, and the high-temperature requirements of LOHC dehydrogenation. By optimizing the PCM formulation and implementing intelligent control, the limitation of traditional solar energy systems not being able to operate around the clock is overcome, achieving significant improvements in energy efficiency and safety compared to conventional electric heating or combustion-assisted solutions.

[0033] Simultaneously, the PLC control module enables dynamic adjustment of HTF flow and precise management of phase change material energy storage, ensuring stable fluctuations (less than ±5℃) in the LOHC dehydrogenation temperature within the range of 250-280℃. The system is equipped with a temperature sensor (accuracy ±1℃), a flow meter (accuracy ±0.5%), and a pressure sensor (accuracy ±0.1 bar) to collect data in real time and optimize HTF flow direction through algorithms, such as prioritizing reactor heating during the day and automatically switching to phase change material heat release mode at night. Compared to traditional solar energy systems that rely on external auxiliary heating, the intelligent thermal management technology of this invention, combined with the isothermal characteristics of the optimized phase change material formulation, significantly improves the system's adaptability and operating efficiency.

[0034] In a preferred embodiment of the present invention, taking a 10kW system as an example, the structure, operation steps and performance parameters of each part are described in detail.

[0035] The system includes a parabolic trough collector, which consists of a parabolic reflector and a receiving tube. The reflector has an area of ​​50 m² and a focal length of 1.5 m. The receiving tube is a vacuum glass tube with an embedded stainless steel absorber tube (50 mm in diameter). The reflector is made of high-reflectivity aluminized glass (reflectivity ≥90%), and the absorber tube is coated with a selective absorption coating (absorptivity ≥95%). The heat transfer medium (HTF) is a synthetic oil (such as Therminol VP-1). The operating temperature range is -20℃ to 400℃, and the target heating temperature is 350℃. Performance: Daytime heat collection is approximately 80 kWh (assuming 6 hours of sunshine and an average irradiance of 800 W / m²), with a heat collection efficiency of 75%.

[0036] The HTF circulation piping system includes a high-temperature centrifugal pump (2 L / s flow rate, 20 m head), heat-resistant piping (Inconel 625, 25 mm inner diameter), and a regulating three-way directional valve (400℃ resistant). Design: The total piping length is approximately 20 m, with an insulation layer (ceramic fiber, 50 mm thick), resulting in heat loss of less than 5%. Operation: The pump is controlled by a frequency converter, and the flow rate is adjusted according to solar energy input and system requirements, typically ranging from 1 to 3 L / s.

[0037] The LOHC dehydrogenation reactor is equipped with a shell-and-tube heat exchanger. The heat exchange medium described above flows through the shell side, while LOHC (perhydrodibenzyltoluene, PDBT) flows through the tube side. Its heat exchange area is 2 m². The shell is made of 316L stainless steel (5 mm thick) with an internal anti-corrosion coating (such as a Ni-Cr coating), and the tube bundle is made of stainless steel (10 mm diameter, 1 mm wall thickness). Operating parameters are: temperature 250-280℃, pressure 1-5 bar, and processing capacity 5 kg / h.

[0038] The PCM energy storage module uses a PCM material formulation with the following weight percentages: NaNO3 95%, LiNO3 4%, MgO 1%, melting point 300°C, latent heat 170 kJ / kg, and a total mass of 1900 kg. The container is a 316L stainless steel cylindrical tank (1 m in diameter, 1.2 m in height), with a wall thickness of 10 mm. The inner wall is polished and coated with an anti-corrosion layer. The heat exchange tubes are stainless steel U-shaped tubes (20 mm in diameter, 50 m in total length), through which HTF flows for heat exchange with the PCM. Its specific performance is a heat storage capacity of 323 MJ, sufficient for 8 hours of nighttime operation (10 kW × 8 h = 80 kWh).

[0039] In this application example, a control system centered on a variable logic controller (VLC) is added. Its hardware includes a PLC (Siemens S7-1200), a temperature sensor (K-type thermocouple, accuracy ±1℃), a flow meter (electromagnetic, accuracy ±0.5%), and a pressure sensor (accuracy ±0.1 bar). The software is a designed computer program that monitors the HTF temperature (350℃ or 300℃), LOHC temperature (260℃), and PCM state (solid / liquid) in real time. This allows for the adjustment of the HTF flow direction via a three-way reversing valve and the driving of the high-temperature pump, prioritizing the reactor during the day and switching to PCM heat release at night.

[0040] In addition to the above, it should be noted that the terms "one embodiment," "another embodiment," and "embodiment" used in this specification refer to specific features, structures, or characteristics described in connection with that embodiment, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this invention.

[0041] Although the invention has been described herein with reference to several illustrative embodiments, it should be understood that many other modifications and implementations can be devised by those skilled in the art, which will fall within the scope and spirit of the principles disclosed herein. More specifically, various variations and modifications can be made to the components and / or layout of the subject matter arrangement within the scope of the disclosure, drawings, and claims. Besides variations and modifications to the components and / or layout, other uses will be apparent to those skilled in the art.

Claims

1. A photothermal supply system for LOHC dehydrogenation, comprising an LOHC dehydrogenation reactor and an HTF circulation pipeline, characterized in that: The HTF circulation pipeline passes through the LOHC dehydrogenation reactor, the parabolic trough collector, and the PCM energy storage module. A high-temperature pump is installed on the HTF circulation pipeline. The high-temperature pump is used to drive the heat exchange medium to transfer heat between the parabolic trough collector and the LOHC dehydrogenation reactor and PCM energy storage module through the HTF circulation pipeline. The PCM energy storage module is filled with a phase change material, which includes 90-100 parts by weight of sodium nitrate, 2-6 parts by weight of lithium nitrate, and 0.5-2 parts by weight of magnesium oxide. A heat exchange tube is installed inside the PCM energy storage module, which is connected to the HTF circulation pipeline, and the phase change material is wrapped around the outside of the heat exchange tube. The parabolic trough collector is equipped with a receiving tube inside, which is located at the heat collection focal point of the parabolic trough collector and is connected to the HTF circulation pipe. The LOHC dehydrogenation reactor has a shell-and-tube heat exchanger, and the wall of the HTF circulation pipe is in contact with the shell-and-tube heat exchanger.

2. The photothermal supply system for LOHC dehydrogenation according to claim 1, characterized in that: The LOHC dehydrogenation reactor, parabolic trough collector, and PCM energy storage module are all installed on a skid-mounted platform.

3. The photothermal supply system for LOHC dehydrogenation according to claim 1 or 2, characterized in that: A flow meter and a pressure sensor are installed on the HTF circulation pipeline; a temperature sensor is installed on the shell-and-tube heat exchanger of the LOHC dehydrogenation reactor; and a temperature sensor is also installed on the phase change material contact point of the PCM energy storage module. A three-way reversing valve is installed on the HTF circulation pipeline. The three-way reversing valve is used to enable the high-temperature pump to drive the heat exchange medium to flow through the parabolic trough collector and the LOHC dehydrogenation reactor, through the parabolic trough collector and the PCM energy storage module, and through the PCM energy storage module and the LOHC dehydrogenation reactor in any one or more flow modes. The temperature sensor, flow meter, pressure sensor, high-temperature pump, and three-way reversing valve are all connected to the control module. The control module is used to control the output power of the high-temperature pump and the reversing state of the three-way reversing valve according to the current temperature of the shell-and-tube heat exchanger of the LOHC dehydrogenation reactor.

4. A photothermal supply method for LOHC dehydrogenation, characterized in that... The method using the system according to any one of claims 1 to 3 includes the following steps: The parabolic trough collector heats the heat exchange medium in the receiving tube to above 350°C by reflecting sunlight. The high-temperature pump drives the heat exchange medium to flow through the shell-and-tube heat exchanger on the LOHC dehydrogenation reactor via the HTF circulation pipeline to exchange heat and maintain the dehydrogenation temperature at 250-280°C. The parabolic trough collector heats the heat exchange medium in the receiving tube to above 350°C by reflecting sunlight. The high-temperature pump drives the heat exchange medium to flow through the heat exchange tube of the PCM energy storage module via the HTF circulation pipe, causing the phase change material to change from solid to liquid and store thermal energy. The high-temperature pump drives the heat exchange medium to flow through the HTF circulation pipeline through the heat exchange tubes of the PCM energy storage module and the shell-and-tube heat exchanger on the LOHC dehydrogenation reactor to exchange heat and maintain the dehydrogenation temperature at 250-280°C.

5. The photothermal supply method for LOHC dehydrogenation according to claim 4, characterized in that: The high-temperature pump drives the heat exchange medium to flow through the parabolic trough collector and the LOHC dehydrogenation reactor, and through the parabolic trough collector and the PCM energy storage module. The PCM energy storage module and the LOHC dehydrogenation reactor are connected to the corresponding parts by controlling the state of the three-way reversing valve through the control module.

6. The photothermal supply method for LOHC dehydrogenation according to claim 4 or 5, characterized in that: The control module acquires the temperature of the shell-and-tube heat exchanger of the current LOHC dehydrogenation reactor through a temperature sensor, the flow rate of the heat exchange medium in the current HTF circulation pipeline through a flow meter, and the pressure of the heat exchange medium in the current HTF circulation pipeline through a pressure sensor, thereby adjusting the output power of the high-temperature pump and the connection status of the three-way reversing valve.

Images