Methanol hydrogen production system coupled with solar energy

Abstract

The invention discloses a solar energy coupled methanol hydrogen production system which comprises a reformer and a solar heating module, and the outlet end and the inlet end of the solar heating module are connected in series through a circulating pipe; the circulating pipe is further provided with a first circulating pump used for driving the heat exchange medium to flow. A bypass pipe for conveying a heat exchange medium to the reformer is also arranged on the circulating pipe; a steam generator and a methanol evaporator are sequentially arranged on the circulating pipe in the flowing direction of the heat exchange medium, and temperature sensors and flow control valves are arranged at the two ends of the circulating pipe; the steam generator is communicated with the steam inlet end of the reformer; the hydrogen production system further comprises a controller, and the controller is electrically connected with the temperature sensor, the flow adjusting valve and the first circulating pump. Heat is provided for production of methanol steam and water vapor through solar heating, and meanwhile it is guaranteed that the internal temperature of the reformer is at the optimal catalytic reaction temperature through solar energy, so that the energy consumption of a hydrogen production system is reduced, and the equipment operation cost is reduced.

Description

Technical Field

[0001] This application relates to the technical field of hydrogen production equipment, and particularly to a methanol hydrogen production system coupled with solar energy. Background Art

[0002] Methanol hydrogen production is a hydrogen production technology route. As the world's largest methanol producer, China has rich raw material sources, which is conducive to reducing the cost of hydrogen production; the basic principle of methanol hydrogen production is to mix methanol and demineralized water, heat and vaporize them, and then enter the reformer after superheating. Methanol and water vapor complete methanol cracking in the reformer under the action of a catalyst, and then hydrogen is generated.

[0003] Methanol hydrogen production is an endothermic reaction, and at the same time, the production of methanol and water vapor also requires a large amount of heat. In the prior art, heat is generally provided by electric heating, resulting in high energy consumption of the methanol hydrogen production system. Summary of the Invention

[0004] The main purpose of this application is to provide a methanol hydrogen production system coupled with solar energy, aiming to solve the defect of high energy consumption in the prior art.

[0005] This application realizes the above purpose through the following technical solutions: A methanol hydrogen production system coupled with solar energy, including a reformer; A solar heating module, the outlet end and the inlet end of the solar heating module are connected in series through a circulation pipe; a first circulation pump for driving the flow of the heat exchange medium is also provided on the circulation pipe; a bypass pipe for delivering the heat exchange medium to the reformer is also provided on the circulation pipe; A methanol evaporator, the methanol evaporator is communicated with the circulation pipe, and the methanol evaporator is communicated with the methanol vapor inlet of the reformer; A steam generator, the steam generator is communicated with the circulation pipe, and along the flow direction of the heat exchange medium, the steam generator is located at the rear end of the methanol generator; temperature sensors and flow control valves are provided at both ends of the circulation pipe; the steam generator is communicated with the steam inlet end of the reformer; A controller, the controller is electrically connected to the temperature sensor, the flow regulating valve and the first circulation pump respectively.

[0006] Optionally, the solar heating module includes a collector and a plurality of solar concentrators, and each solar concentrator aggregates and reflects sunlight onto the collector.

[0007] Optionally, the collector includes a box body, and a heat pipe module is arranged in the box body; a heat storage medium is also filled in the box body, and the heat storage medium wraps the heat pipe module.

[0008] Optionally, the heat pipe module includes an inlet pipe, an outlet pipe, and a plurality of independent spiral pipes. Each of the spiral pipes is coaxially nested in sequence around the same axis. The inlet ends of the spiral pipes are respectively connected in parallel with the inlet pipe, and the outlet ends of the spiral pipes are respectively connected in parallel with the outlet pipe.

[0009] Optionally, the hydrogen production system further includes a heat storage tank. A first branch is connected in parallel to the circulation pipe. The heat storage tank is arranged on the first branch. A regulating valve is arranged at the inlet end of the first branch, and a second circulation pump electrically connected to the controller is further arranged at the outlet end of the first branch.

[0010] Optionally, a buffer tank is further arranged at the outlet end of the circulation pipe. The inlet end of the buffer tank is communicated with the methanol evaporator. The outlet end of the buffer tank is connected to the inlet end of the collector through a third circulation pump. The third circulation pump is electrically connected to the controller.

[0011] Optionally, a second branch is further arranged on the circulation pipe. A spare heating pipe is arranged on the second branch. A metal heating rod is arranged inside the spare heating pipe, and an eddy current heating coil for heating the metal heating rod is sleeved on the spare heating pipe.

[0012] Optionally, the methanol hydrogen production system further includes a steam power generation module and a storage battery. An output end of the steam generator is connected in parallel with a steam pipe communicated with the steam power generation module; the steam power generation module is electrically connected to the storage battery; an output end of the storage battery is electrically connected to the eddy current heating coil through an inverter.

[0013] Optionally, the steam power generation module includes a steam turbine. The steam turbine is communicated with the steam pipe. A condenser and a return water pump connected in series in sequence are further arranged on the steam turbine. An outlet end of the return water pump is communicated with the steam generator.

[0014] Optionally, the controller includes an industrial personal computer and a PLC. The industrial personal computer is electrically connected to the PLC.

[0015] Compared with the prior art, the present application has the following beneficial effects: The present application includes a reformer and a solar heating module. An outlet end and an inlet end of the solar heating module are connected in series through a circulation pipe; a first circulation pump for driving a heat exchange medium to flow is further arranged on the circulation pipe; a bypass pipe for delivering the heat exchange medium to the reformer is further arranged on the circulation pipe; along the flowing direction of the heat exchange medium, a steam generator and a methanol evaporator are further arranged in sequence on the circulation pipe. Temperature sensors and flow control valves are arranged at both ends of the circulation pipe; the steam generator is communicated with a steam inlet end of the reformer; the hydrogen production system further includes a controller, and the controller is electrically connected to the temperature sensor, the flow regulating valve, and the first circulation pump respectively.

[0016] When the hydrogen production system described in this application is in use, the solar heating module heats the heat exchange medium through sunlight. At the same time, the heat exchange medium after heating flows along the circulation pipe driven by the first circulation pump. Part of the heat exchange medium passes through the steam generator and the methanol evaporator successively to generate water vapor and methanol vapor; another part of the heat exchange medium enters the bypass pipe and finally enters the reformer. The reformer catalyst in the reformer is heated by the heat exchange medium to keep it at the optimal catalytic temperature, so as to convert methanol into hydrogen and finally transport it to the storage device; Compared with the prior art, this application provides heat for the production of methanol vapor and water vapor through solar heating, and at the same time ensures that the internal temperature of the reformer is at the optimal catalytic reaction temperature through solar energy, thereby reducing the energy consumption of the entire hydrogen production system and the cost of equipment operation; Secondly, this application is provided with a circulation pipe and a bypass pipe in parallel. The circulation pipe provides heat for the methanol evaporator and the steam generator, while the bypass pipe provides heat for the reformer. Its layout is ingenious through the different working temperatures of each device, which not only ensures that each device is within the maximum working temperature, but also can improve the utilization rate of heat as much as possible, further reducing the energy consumption of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of a combined hydrogen production system coupling solar energy and a reforming fuel cell provided in Embodiment 1 of this application; Figure 2 It is a schematic structural diagram of a collector; Figure 3 It is a schematic structural diagram of a heat pipe module; Figure 4 It is a schematic structural diagram of a spare heating pipe;

[0018] Reference numerals: 1 - reformer, 2 - circulation pipe, 3 - first circulation pump, 4 - bypass pipe, 5 - methanol evaporator, 6 - steam generator, 7 - temperature sensor, 8 - flow regulating valve, 9 - collector, 10 - solar concentrator, 11 - heat storage tank, 12 - first branch, 13 - regulating valve, 14 - second circulation pump, 15 - buffer tank, 16 - third circulation pump, 17 - second branch, 18 - spare heating pipe, 19 - metal heating rod, 20 - eddy current heating coil, 21 - storage battery, 22 - steam pipe, 23 - inverter, 24 - steam turbine, 25 - condenser, 26 - water return pump, 27 - industrial control computer, 28 - PLC, 901 - box body, 902 - heat storage medium, 903 - inlet pipe, 904 - outlet pipe, 905 - spiral pipe.

[0019] The realization of the purpose, functional features and advantages of this application will be further described with reference to the embodiments and the accompanying drawings. Detailed implementation manners

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0021] It should be noted that all directional indications (such as up, down, left, right, front, back,...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0022] In the present invention, unless otherwise clearly defined and limited, the terms "connection", "fixation", etc. shall be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0023] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one such feature. In addition, the meaning of "and / or" appearing throughout the text includes three parallel solutions. Taking "robot coordinate system and / or m" as an example, it includes the robot coordinate system solution, the m solution, or the solution where the robot coordinate system and m are satisfied simultaneously. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0024] Embodiment 1 Refer to Figures 1 to 4, this embodiment discloses a methanol hydrogen production system coupled with solar energy, including a reformer 1 and a solar heating module. The solar heating module includes a collector 9 and a number of solar concentrators 10. Among them, the solar concentrator 105 is a solar reflector. It should be noted that the solar reflector can adopt a curved surface structure or a flat surface structure, and the number of solar reflectors is determined according to actual needs; Preferably, the solar concentrator 10 adopts a flat plate structure, and each solar concentrator 10 is arranged around the collector 9. At the same time, after each solar concentrator 10 reflects sunlight, the light irradiates onto the collector 9; In order to further improve the uniformity of heat reception of the collector 9, each of the solar concentrators 10 is arranged on multiple different circular trajectories, and the reflection points of the solar concentrators 10 located in the same radial direction are spliced in sequence to completely wrap the collector 9.

[0025] The collector 9 includes a box body 901. It should be noted that a heat pipe module is arranged inside the box body 901, and at the same time, a heat storage medium 902 is filled inside the box body 901, and the heat storage medium 902 completely wraps the heat pipe module; The heat pipe module includes an inlet pipe 903, an outlet pipe 904 and a number of independent spiral pipes 905. The outer diameters of the spiral pipes 905 decrease linearly, and at the same time, the spiral pipes 905 are coaxially nested in sequence around the same axis. The inlet ends of the spiral pipes 905 are respectively connected in parallel with the inlet pipe 903, and the outlet ends of the spiral pipes 905 are respectively connected in parallel with the outlet pipe 904; Both the inlet pipe 903 and the outlet pipe 904 extend out of the box body 901 to connect to external pipelines; In the above structure, there are a number of spiral pipes 905, and the spiral pipes 905 are coaxially nested in sequence around the same axis. Through the above structure, the internal spaces of the spiral pipes 905 can be filled, and the flow rate of the heat pipe module can be increased as much as possible, so as to increase the amount of heat exchange medium heated per unit time; Secondly, the spiral pipes 905 are separated from each other, that is, multiple heating pipelines are arranged in parallel in the heat collection box. On the one hand, when one pipeline is blocked, the equipment can still work normally, which is beneficial to improving the stability and reliability of the equipment; on the other hand, the heat exchange medium is separated and heated separately by the separated spiral pipes 905, which can effectively increase the contact area between the heat exchange medium and the heat storage medium 902. Coupled with the spiral structure, the length of the pipeline is extended, and it can effectively ensure the temperature of the heat exchange medium at the outlet end of the collector 9; Finally, through the absorption and re-release of heat by the heat storage medium 902, on the one hand, it can balance the fluctuations of solar radiation, ensure the stable output of heat, and thus ensure the stability of the temperature of the heat exchange medium; on the other hand, on the premise of ensuring the temperature of the heat exchange medium, the excess heat is stored inside and released when the solar radiation is insufficient, so as to ensure that the whole system can work normally at night or on cloudy days and ensure the effective working time of the equipment.

[0026] The hydrogen production system further includes a circulation pipe 2 and a bypass pipe 4. The inlet end of the bypass pipe 4 is connected to the outlet end of the collector 9 in parallel with the circulation pipe 2, that is, connected to the outlet end of the collector 9. Along the flow direction of the heat exchange medium, a methanol evaporator 5 and a steam generator 6 are sequentially arranged on the circulation pipe 2, and the bypass pipe 4 is connected to the reformer 1. At the same time, the methanol inlet of the methanol evaporator 5 is communicated with an external methanol source, and the water injection port of the steam generator is connected to an external water source. The methanol vapor outlet of the methanol evaporator 5 is connected to the methanol vapor inlet end of the reformer 1, and the steam outlet of the steam generator is connected to the steam inlet end of the reformer 1 to respectively input methanol vapor and water vapor into the reformer 1; at the same time, the heat exchange medium input through the bypass pipe 4 maintains the reaction temperature in the reformer 1. A first circulation pump 3 is also arranged on the circulation pipe 2, and at the same time, the circulation pipe 2 is connected to the bypass pipe 4 through a flow regulating valve 8. The hydrogen production system further includes a buffer tank 15. The buffer tank 15 is arranged at the outlet end of the circulation pipe 2, that is, the inlet end of the buffer tank 15 is communicated with the outlet of the methanol evaporator 5, and the outlet end of the buffer tank 15 is connected to the inlet pipe 903 of the collector 9. A third circulation pump 16 is also arranged between the buffer tank 15 and the collector 9. It should be noted that the outlet end of the bypass pipe 4 is connected to the buffer tank 15 in parallel with the circulation pipe 2. At the same time, a heat insulation layer is wrapped on the outer surface of the buffer tank 15 to avoid heat dissipation. Temperature sensors 7 and flow regulating valves 8 are arranged at the outlet and inlet of the circulation pipe 2 and the inlet end of the bypass pipe 4. The function of the buffer tank 15 can adjust the flow rate at the inlet end of the heat exchanger, that is, flexibly adjust the flow rate of the heat exchange medium according to the change of solar radiation, ensure that the heat exchange medium can enter and exit the collector 9 with stable temperature and flow rate, and thus ensure the stable operation of each device. Secondly, with the above settings, the circulation pipe 2 and the bypass pipe 4 are two parallel pipelines. Compared with a single series structure, the parallel structure can ensure that the inlet temperatures of the heat exchange medium at the inlet ends of the two pipelines are the same, thus avoiding the rapid attenuation of the heat of the heat exchange medium due to too many heat-consuming devices in series, and further ensuring that the inlet temperatures of all components that require heating by the heat exchange medium can meet the technical requirements; Secondly, since the above structure ensures the inlet temperatures of each branch, it can ensure that each device operates at the optimal temperature. Especially when there are multiple devices with high requirements for the heat quality temperature, the above structure can ensure that each device can stably produce various raw materials, and further ensure the continuous and stable operation of the entire system; At the same time, it should be noted that while ensuring the inlet temperatures of each device, it can also ensure that each device can always operate stably in the optimal thermal efficiency range. For example, the evaporation temperature of water exceeds 100 °C, while the boiling point of methanol under normal pressure is 64 °C. Through the above settings, it can ensure that the heat exchange medium first flows into the steam generator 6 and then into the methanol evaporator 5. Since the steam generator 6 will consume part of the heat, thereby reducing the temperature of the heat exchange medium, it can ensure that both the steam generator 6 and the methanol evaporator 5 can operate at the optimal evaporation temperature, and further ensure that the entire system can operate stably in the optimal state, which is beneficial to improving the operating efficiency of the equipment, that is, improving the thermal efficiency of the entire system.

[0027] The hydrogen production system further includes a heat storage tank 11. A first branch 12 is also provided in parallel on the circulation pipe 2. The heat storage tank 11 is connected to the first branch 12. A regulating valve 13 is provided at the inlet end of the heat storage tank 11, and a second circulation pump 14 is provided at the outlet end of the heat storage tank 11; In the system startup stage, the first branch 12 is closed through the regulating valve 13. At this time, the amount of heat exchange medium that needs to be heated can be reduced, thereby quickly increasing the temperature of the heat exchange medium and realizing the rapid startup of the equipment; When the equipment is fully started, the heat exchange medium is gradually increased into the circulation pipe 2 through the opening adjustment of the regulating valve 13 and the second circulation pump 14, and the excess heat exchange medium is stored in the heat storage tank 11 again. On the one hand, it can store more heat under high solar radiation conditions, which is beneficial to improving the continuous and stable operation of the equipment at night or under low solar radiation conditions; on the other hand, when the heat exchange medium is insufficient, the heat storage tank 11 can quickly supplement a large amount of qualified heat exchange medium for the circulation pipe 2 to ensure the stable operation of the system; It should be noted that a sandwich layer can also be provided in the heat storage tank 11, and a heat storage medium 902 is filled in the sandwich layer, so as to store more heat through the heat storage medium 902; Secondly, during the storage of the heat exchange medium, heat dissipation is inevitable. At this time, the heat storage medium 902 can absorb the dissipated heat and reduce heat loss. Finally, when the heat exchange medium in the heat storage tank 11 is enabled, the temperature of the heat exchange medium will continue to decrease. At this time, the heat storage medium 902 can continuously heat the heat exchange medium to ensure that the temperature of the output heat exchange medium meets the requirements, thereby increasing the effective working time of the equipment under harsh working conditions.

[0028] The circulation pipe 2 is further provided with a second branch 17. The inlet end of the second branch 17 is connected in parallel with the inlet end of the buffer tank 15, and the outlet end of the second branch 17 is connected in parallel with the outlet end of the buffer tank 15. Solenoid valves are provided at both ends of the second branch 17. A spare heating pipe 18 is provided on the second branch 17. A metal heating rod 19 is provided inside the spare heating pipe 18, and an eddy current heating coil 20 for heating the metal heating rod 19 is sleeved on the spare heating pipe 18. The eddy current heating coil 20 is electrically connected to an external AC power supply. In the above structure, the spare heating pipe 18 is made of a non-metallic material. At the same time, the metal heating rod 19 is preferably made of a steel or copper structure. Since the metal heating rod 19 is directly placed in the heat exchange medium, it can directly heat the heat exchange medium, thereby improving the heating efficiency. At the same time, the eddy current heating coil 20 also has a high heating efficiency. Although the buffer tank 15 has many advantages, because it stores a large amount of heat exchange medium, when the heat stored in the entire system continues to decrease and the spare heating pipe 18 needs to supplement heat to the system, in unit time, the heat generated by the spare heating pipe 18 is limited. The low-temperature heat exchange medium stored in the buffer tank 15 will largely neutralize the heated high-temperature heat medium, seriously affecting the heating efficiency of the entire system. At this time, the buffer tank 15 will cause the temperature of the heat exchange medium in the entire system not to be effectively increased in a short time. At this time, through the second branch 17, heat can be directly and quickly injected into the circulation pipe 2 of the entire system, bypassing the buffer tank 15, thereby quickly increasing the temperature of the heat exchange medium flowing in the system, which is beneficial to improving the flow efficiency of heat in the entire system and ensuring the stable operation of the system. Secondly, compared with the total amount of the heat exchange medium in the system, the flowing heat exchange medium only accounts for a part. Therefore, its heating speed is faster. The above technical measures can better ensure the stable operation of the system. At the same time, after heating the flowing heat exchange medium, through the flow regulating valve 8, the heat exchange medium in the buffer tank 15 can be gradually heated, and finally the temperature of the entire system can be maintained within the working range, ensuring the stability and reliability of the system operation.

[0029] Finally, the above extreme working conditions can be quickly processed through the separately provided second branch 17, which has a simple structure and convenient operation, and is also beneficial to reducing the cost of the entire system.

[0030] The hydrogen production system further includes a steam power generation module and a storage battery 21. The steam power generation module includes a steam turbine 24. A steam pipe 22 communicating with the steam turbine 24 is connected in parallel to the steam output end of the steam generator 6. A regulating valve 13 for controlling its on-off state is provided at the inlet end of the steam pipe. The output end of the steam turbine 24 is connected to a generator, and the generator is electrically connected to the storage battery 21 through a rectifier; the output end of the storage battery 21 is electrically connected to the eddy current heating coil through an inverter 23; At the same time, a condenser 25 and a return water pump 26 connected in series are further provided on the steam turbine 24. The outlet end of the return water pump 26 communicates with the steam generator 6, so as to realize the reflux and reuse of the condensed water. When the solar radiation is large and both the heat storage tank 11 and the heat storage medium 902 reach the heat storage upper limit, the steam pipe 22 is opened, and the working efficiency of the steam generator 6 is increased to generate more water vapor. The excess water vapor will drive the steam turbine 24 to generate electricity, and the alternating current generated by the steam turbine 24 is charged to the storage battery 21 through a rectifier; Under the working conditions of night or low solar radiation, if the heat stored in the heat storage medium 902 and the heat storage tank 11 cannot maintain the normal operation of the system, the first branch 12 and the buffer tank 15 are closed, and at the same time the second branch 17 is opened. At the same time, the storage battery 21 supplies power to the standby heating pipe 18, and then directly heats the heat exchange medium through the metal heating rod 19 to ensure the temperature of the heat exchange medium; Since the total amount of the heat exchange medium in the system is limited, there is a certain upper limit to the heat that the system can store. Under the working conditions of strong light, the heat concentrated by the solar concentrator 10 may be much higher than the upper limit of the heat stored in the system. In this case, the present application consumes a large amount of water vapor by starting the steam turbine 24, thereby increasing the heat consumption of the steam generator 6, which is beneficial to the efficient utilization of the excess heat and improves the energy stored in the entire system; And the above stored energy is output under the working conditions of night and low solar radiation, so as to ensure the stable operation of the entire system and ensure that the system can work continuously for 24 hours with only solar energy as the energy input; At the same time, since the eddy current heating coil 20 is also directly connected to an external power supply, the stable operation of the system can be ensured by the input of the external power supply under extreme working conditions, and the system can work stably and continuously for 24 hours; It should be noted that several steam turbines 24 and heat storage tanks 11 can be provided. The pipelines of each steam turbine 24 are connected in parallel and then connected to the steam generator 6, so as to provide a greater operating redundancy for the system and meet the usage requirements under various extreme working conditions.

[0031] Compared with the prior art, the above technical solution can not only improve the economy of the whole system operation, but also effectively balance the heat in the system, thereby ensuring the safe and stable operation of the system under extreme working conditions and improving the adaptability of the equipment.

[0032] The combined hydrogen production system further includes a controller, and each of the temperature sensors 7, each of the flow regulating valves 3, the regulating valve 13 and each circulation pump are electrically connected to the controller 4.

[0033] Specifically, the controller includes a data input module, a command output control module and a main controller. The data input module includes: a solar direct irradiance intensity sensor, a plurality of flow sensors, a plurality of flow regulating valves and a plurality of temperature sensors.

[0034] The solar direct irradiance intensity sensor is arranged on the solar concentrator panel for real-time monitoring of the solar direct irradiance intensity. The temperature sensor is used to detect the temperature of the heat exchange medium in different areas of the hydrogen production system; the flow regulating valve and the flow sensor cooperate with each other to detect the flow of the heat exchange medium in each branch. The output control module includes: Module 1, which is connected to all the flow regulating valves and each circulation pump in the circulation pipe and the bypass pipe, is used to control the temperature, flow velocity and flow of the heat exchange medium, and at the same time control the on-off state of each pipeline. Module 2, which is connected to the regulating valve solenoid valves at both ends of the second branch, is used to control the on-off state of the second branch, that is, to enable and close the second branch. Module 3, which is electrically connected to the regulating valve and the second circulation pump on the first branch, is used to recover the excess heat in time and release the stored heat exchange medium at the same time. Module 4, which is electrically connected to the flow regulating valve, the return water pump, etc. on the steam pipe, is used to control the temperature and flow of the water vapor in the steam power generation loop. Module 5, which is electrically connected to the battery module group and also controls the on-off state of the mains network to ensure the timely power supply to the standby heating pipe under extreme conditions and ensure the stable operation of the system in an extreme environment.

[0035] Correspondingly, the present application also discloses an operation method of the above methanol hydrogen production system, including the following steps: S1. Start the system; At startup, first determine whether the light intensity can meet the startup requirements. If it cannot be met, start by providing auxiliary heat through the backup heating tube. If the light intensity meets the requirements, start the system by gradually heating through the solar heating module; It should be noted that the startup of the system can also be achieved by using the high-temperature heat exchange medium stored in the heat storage tank and the heat storage medium stored in the collector tank; S2. During the operation of the system, monitor the temperature of the heat exchange medium through the temperature sensor, and at the same time monitor whether the direct solar radiation intensity meets the requirements through the illuminance sensor; When the direct solar radiation intensity meets the value for the normal operation of the system, adjust the flow rates of the circulation pipe and the bypass pipe according to the temperature data of the heat exchange medium measured by the temperature sensors at the inlet and outlet of the collector. At the same time, open the first branch. While ensuring the operation of the system, gradually increase the amount of heat exchange medium stored in the heat storage tank. If the opening of the first branch has an adverse effect on the normal operation of the system, the first branch must be immediately closed; at this time, all the heat required for the operation of the entire system is provided by the solar energy converged by the solar collector.

[0036] When the direct solar radiation intensity exceeds the value for the normal operation of the system, gradually open the first branch at this time, and at the same time inject a heat exchange medium with a lower temperature into the circulation pipe and the bypass pipe through the second circulation pump to adjust the temperature of the heat exchange medium. At the same time, recover the excess heat exchange medium after heating, control the flow rate of the heat exchange medium in the heat and mass circulation pipe, and store the excess part of the heat in the heat storage tank for use when the subsequent solar radiation intensity decreases.

[0037] When the direct solar radiation intensity is long-term high, the heat of the circulating working medium stored in the heat storage tank reaches the limit, and at the same time the heat storage medium in the collector cannot accumulate more heat, start the steam turbine and its auxiliary pipelines, and consume the excess heat by generating electricity through the steam turbine and charging the battery, so as to balance the heat of the entire system; When the direct solar radiation intensity is lower than the value for the normal operation of the system, the temperature of the heat exchange medium in the entire system decreases. At this time, first determine that the heat stored in the heat storage medium cannot supplement the heat of the system. At this time, open the first branch, and at the same time input a high-temperature heat exchange medium into the circulation pipe and the bypass pipe through the second circulation pump to stabilize the temperature of the heat exchange medium in the entire system; When the temperature in the system drops again after running smoothly for a period of time, determine that the heat stored in the heat exchange medium in the heat storage tank cannot supplement the heat of the system. At this time, close the first branch and the buffer tank, drive the backup heating tube to work through the battery, and at the same time directly heat the heat exchange medium in the circulation pipe through the backup heating tube, so as to stabilize the stable balance of the entire system in the shortest time, and at the same time ensure that the system maintains operation with the heat exchange medium at the lowest flow rate, It should be noted that the power of the standby heating pipe is controlled and corrected according to the temperature of the heat exchange medium measured by the temperature sensors at the inlet and outlet of the collector.

[0038] Through the above control method, the hydrogen production system can operate continuously for 24 hours under different solar radiation intensities, allocate the input shares of two energy sources, solar energy and reserve energy (heat storage and power storage), and eliminate the influence of unstable power generation caused by the change of solar radiation intensity. It should be noted that the above control method needs to be flexibly switched according to the light. Compared with the prior art, in this application, solar heating is used to provide heat for the production of methanol vapor and water vapor, and at the same time, solar energy is used to ensure that the internal temperature of the reformer is at the optimal catalytic reaction temperature. The heat source of the whole system is mainly solar energy, which is not only cheap but also has a wide source. Moreover, more solar energy can be collected by adding solar reflectors. Therefore, it can further reduce the operation cost of the equipment, improve the economy of the whole system, thus reducing the energy consumption of the whole hydrogen production system and the operation cost of the equipment. Secondly, a circulation pipe and a bypass pipe are arranged in parallel in this application. The circulation pipe provides heat for the methanol evaporator and the steam generator, while the bypass pipe provides heat for the reformer. Through the ingenious layout according to the different working temperatures of each device, it not only ensures that each device is within the maximum working temperature, but also can improve the utilization rate of heat as much as possible, further reducing the energy consumption of the equipment.

[0039] The above are only the preferred embodiments of this application, and do not limit the patent scope of this application accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of this application, or directly or indirectly applied in other related technical fields, shall be included in the patent protection scope of this application by the same token.

Claims

1. A methanol hydrogen production system coupled with solar energy, characterized in that: comprising a reformer (1); A solar heating module, wherein the outlet end and the inlet end of the solar heating module are connected in series via a circulation pipe (2); the circulation pipe (2) is also provided with a first circulation pump (3) for driving the flow of a heat exchange medium; the circulation pipe (2) is also provided with a bypass pipe (4) for conveying the heat exchange medium to the reformer (1); A methanol evaporator (5), the methanol evaporator (5) being in communication with the circulation pipe (2), and the methanol evaporator (5) being in communication with the methanol vapor inlet of the reformer (1); a steam generator (6), the steam generator (6) being in communication with the circulation pipe (2), and being located at the rear end of the methanol generator along the flow direction of the heat exchange medium; temperature sensors (7) and flow regulating valves (8) are provided at both ends of the circulation pipe (2); the steam generator (6) is in communication with the steam inlet end of the reformer (1); A controller, wherein the controller is electrically connected to the temperature sensor (7), the flow regulating valve (8) and the first circulation pump (3) respectively.

2. A methanol-to-hydrogen system coupled with solar energy according to claim 1, characterized in that: The solar heating module comprises a heat collector (9) and a plurality of solar concentrators (10), each of the solar concentrators (10) concentrating and reflecting sunlight onto the heat collector (9).

3. A methanol-to-hydrogen system coupled with solar energy according to claim 2, characterized in that: The heat collector (9) comprises a box (901), wherein a heat pipe module is arranged in the box (901); the box (901) is also filled with a heat storage medium (902), and the heat storage medium (902) wraps the heat pipe module.

4. A methanol-to-hydrogen system coupled with solar energy according to claim 3, characterized in that: The heat pipe module comprises an inlet pipe (903), an outlet pipe (904) and a plurality of mutually independent spiral pipes (905), wherein the spiral pipes (905) are coaxially nested in sequence around the same axis, and the inlet end of each spiral pipe (905) is respectively connected in parallel with the inlet pipe (903), and the outlet end of each spiral pipe (905) is respectively connected in parallel with the outlet pipe (904).

5. The methanol-to-hydrogen system coupled with solar energy according to claim 1, characterized in that: The hydrogen production system further comprises a heat storage tank (11), a first branch (12) is connected in parallel to the circulation pipe (2), the heat storage tank (11) is arranged on the first branch (12), a regulating valve (13) is arranged at the inlet end of the first branch (12), and a second circulation pump (14) electrically connected to the controller is also arranged at the outlet end of the first branch (12).

6. The solar-coupled methanol hydrogen production system according to claim 2, characterized in that: A buffer tank (15) is also provided at the outlet end of the circulation pipe (2), the inlet end of the buffer tank (15) is connected to the methanol evaporator (5), the outlet end of the buffer tank (15) is connected to the inlet end of the collector (9) via a third circulation pump (16), and the third circulation pump (16) is electrically connected to the controller.

7. The solar-coupled methanol hydrogen production system according to claim 1, characterized in that: The circulation pipe (2) is also provided with a second branch (17), the second branch (17) is provided with a spare heating pipe (18), a metal heating rod (19) is provided inside the spare heating pipe (18), and an eddy current heating coil (20) for heating the metal heating rod (19) is sleeved on the spare heating pipe (18).

8. The solar-coupled methanol hydrogen production system according to claim 7, characterized in that: The methanol hydrogen production system also includes a steam power generation module and a storage battery (21); the output end of the steam generator (6) is connected in parallel with a steam pipe (22) connected to the steam power generation module; the steam power generation module is electrically connected to the storage battery (21); and the output end of the storage battery (21) is electrically connected to the eddy current heating coil (20) via an inverter (23).

9. A methanol-to-hydrogen system coupled with solar energy according to claim 8, characterized in that: The steam power generation module comprises a steam turbine (24), the steam turbine (24) being connected to the steam pipe (22), and the steam turbine (24) being further provided with a condenser (25) and a return water pump (26) which are connected in series in sequence, and the outlet end of the return water pump (26) being connected to the steam generator (6).

10. The solar-coupled methanol hydrogen production system according to claim 1, characterized in that: The controller comprises an industrial computer (27) and a PLC (28), and the industrial computer (27) is electrically connected to the PLC (28).

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