Device and process method for preparing formic acid through electro-catalysis in pressurized water reactor environment

Abstract

The invention provides a device and a process method for preparing formic acid through electro-catalysis in a pressurized water reactor environment, and relates to the field of comprehensive utilization of nuclear energy. The device comprises a pressurized water reactor first loop system, a circulating water second loop system and an electrolytic formic acid preparation device. The pressurized water reactor first loop system comprises a reactor, a voltage stabilizer, a steam generator and a coolant pump, the coolant pump is used for driving a coolant to circulate in the first loop, and the coolant is used for conveying heat generated by the reactor to the steam generator to exchange heat with the circulating water second loop system; the circulating water second loop system comprises a steam turbine, a condenser, a cooling water source and a steam generator, the steam turbine, the condenser, the cooling water source and the steam generator are sequentially connected to form a second loop, and cooling water exchanges heat with the coolant in the steam generator. A pressurized water reactor power generation system is combined with a system for preparing formic acid through electrocatalytic carbon dioxide reduction, and the overall energy conversion efficiency and the comprehensive energy utilization level of a nuclear energy power generation system are effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of nuclear energy comprehensive utilization, in particular to a device and process for electrocatalytic preparation of formic acid under the environment of pressurized water reactor. BACKGROUND

[0002] Generating electricity by nuclear reaction is an important development trend in the field of energy today. The pressurized water reactor technology has a significant application advantage because of its mature technology, stable operation and high safety, and occupies a dominant position in the global nuclear power installed capacity. However, in the actual operation process, the energy comprehensive utilization efficiency of the pressurized water reactor nuclear power plant is still at a low level. At present, most of the system designs still aim at single power generation, and the graded efficient use of the energy generated by nuclear reaction cannot be realized. SUMMARY

[0003] The present application discloses a device for electrocatalytic preparation of formic acid under the environment of pressurized water reactor and a process for electrocatalytic preparation of formic acid by using the device. The system and method combine the pressurized water reactor power generation system and the electrocatalytic carbon dioxide reduction system for preparing formic acid, which can realize the resource utilization of carbon dioxide and the green synthesis of formic acid while ensuring the continuous and stable operation of the nuclear power plant at the optimal power level, thereby improving the overall energy conversion efficiency and the comprehensive energy utilization level of the nuclear power generation system.

[0004] The embodiments of the present application can be implemented as follows: The embodiments of the present application provide a device for electrocatalytic preparation of formic acid under the environment of pressurized water reactor. The device comprises a pressurized water reactor first loop system, a circulating water second loop system and an electrolytic formic acid preparation device. The pressurized water reactor first loop system comprises a reactor, a pressurizer, a steam generator and a coolant pump. The reactor, the pressurizer and the steam generator are connected in sequence to form a first loop. The coolant pump is used to drive the coolant to circulate in the first loop. The coolant is used to transport the heat generated by the reactor to the steam generator, and then exchanges heat with the circulating water second loop system. The steam generator is connected with the circulating water second loop system and the electrolytic formic acid preparation device. The circulating water second loop system comprises a steam turbine, a condenser, a cooling water source and the steam generator. The steam turbine, the condenser, the cooling water source and the steam generator are connected in sequence to form a second loop. The cooling water circulates and flows in the second loop, and exchanges heat with the coolant in the steam generator. The electrolytic formic acid preparation device is connected with the steam turbine through the generator.

[0005] Optionally, the steam turbine has an inlet and an outlet. The inlet is connected with the steam generator. The exhaust steam discharged from the outlet is used to supply heat to the electrolytic formic acid preparation device.

[0006] Optionally, the device for preparing formic acid by electrocatalysis under the environment of pressurized water reactor further comprises an intelligent scheduling controller, an input end of the intelligent scheduling controller being connected with the generator, and an output end of the intelligent scheduling controller being connected with the device for preparing formic acid by electrolysis and an electric power system, for receiving a power demand signal of the device for preparing formic acid by electrolysis and the electric power system, and performing real-time distribution and power scheduling on the electric energy generated by the generator based on the demand signal.

[0007] Optionally, the intelligent scheduling controller further comprises a first switch and a second switch, the first switch being located on a line between the generator and the electric power system, for controlling on-off of the line between the generator and the electric power system, and the second switch being located on a line between the generator and the device for preparing formic acid by electrolysis, for controlling on-off of the line between the generator and the device for preparing formic acid by electrolysis.

[0008] Optionally, the device for preparing formic acid by electrocatalysis under the environment of pressurized water reactor further comprises a rectifier, the rectifier being used for converting alternating current output by the generator into direct current, one end of the rectifier being electrically connected with the generator, and the other end of the rectifier being electrically connected with the device for preparing formic acid by electrolysis.

[0009] Optionally, the device for preparing formic acid by electrocatalysis under the environment of pressurized water reactor further comprises a steady current power supply module, an input end of the steady current power supply module being connected with an output end of the rectifier, for converting the direct current output by the rectifier into direct current with stable current.

[0010] Optionally, the device for preparing formic acid by electrolysis comprises a reaction tank, an anode, a diaphragm, a cathode, an electrolyte, and a carbon dioxide feeding device, the carbon dioxide feeding device being used for feeding carbon dioxide into the reaction tank, and an output end of the steady current power supply module being connected with positive and negative electrodes of the device for preparing formic acid by electrolysis, for providing stable direct current for electrolysis reaction.

[0011] Optionally, the device for preparing formic acid by electrolysis further comprises an electrolyte circulating device, for driving the electrolyte to circulate in the reaction tank at a set flow rate.

[0012] The embodiment of the present application provides a process method for preparing formic acid by electrocatalysis, which utilizes the device for preparing formic acid by electrocatalysis under the environment of pressurized water reactor to perform reaction, and the electrolyte circulates at a flow rate of 2-5 mL / min during the reaction of preparing formic acid by electrocatalysis.

[0013] Optionally, the device for preparing formic acid by electrolysis applies a reduction potential of 1-5 V during the reaction of preparing formic acid by electrocatalysis.

[0014] The device for preparing formic acid by electrocatalysis under the environment of pressurized water reactor of the embodiment of the present application has the following advantages, for example: The high-efficiency coupling of a nuclear energy system and a chemical synthesis system is realized by integrating a pressurized water reactor first loop system, a circulating water second loop system and a formic acid electrolysis device. The formic acid electrolysis device under the pressurized water reactor environment fully utilizes the high-grade heat energy carried by the pressurized water reactor first loop coolant, heats the second loop circulating water through a steam generator and generates steam, drives a steam turbine to generate power, and provides a stable power supply for the chemical reaction process of electrolytic formic acid production. The scheme converts carbon dioxide into high-value-added formic acid products, realizes 'product carbon fixation', and provides a paradigm for developing negative carbon technology and building a green circular economy. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0016] Figure 1 A schematic diagram of the formic acid electrolysis device under the pressurized water reactor environment provided for the present embodiment; Figure 2 A relationship curve diagram of the formic acid electrolysis process reduction voltage and formic acid yield provided for the present embodiment; Figure 3 A relationship curve diagram of the formic acid electrolysis process reduction voltage and formic acid energy efficiency provided for the present embodiment.

[0017] Icon: 10 - formic acid electrolysis device under pressurized water reactor environment; 100 - pressurized water reactor first loop system; 200 - circulating water second loop system; 300 - formic acid electrolysis device; 110 - reactor; 120 - pressurizer; 130 - steam generator; 140 - coolant pump; 210 - steam turbine; 220 - condenser; 230 - cooling water source; 400 - generator; 211 - inlet; 212 - outlet; 600 - power system; 201 - first feedwater pump; 202 - second feedwater pump. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, not all embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the application provided in the drawings is not intended to limit the scope of the application claimed, but merely represents selected embodiments of the application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the application without creative labor fall within the scope of the application.

[0020] It should be noted that similar reference numbers and letters represent similar items in the following drawings, and therefore, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings.

[0021] In the description of the application, it should be noted that if the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed, and are only for the convenience of describing the application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.

[0022] In addition, if the terms "first", "second", and the like appear, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance. In addition, in the description of the present application, "a plurality of" means two or more than two, unless otherwise specified and limited.

[0023] It should be noted that unless otherwise specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected or can communicate with each other; it can be directly connected, or indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0024] It should also be noted that the features in the embodiments of the application can be combined with each other without conflict.

[0025] As described in the background, the energy comprehensive utilization efficiency is low in the process of power generation using a pressurized water reactor, the application provides a device 10 and a process method for preparing formic acid by electrocatalysis in a pressurized water reactor environment, which combines a pressurized water reactor power generation system with an electrocatalytic carbon dioxide reduction system to prepare formic acid, effectively improves the overall energy conversion efficiency and comprehensive energy utilization level of the nuclear power generation system, and realizes efficient coupling of the nuclear energy system and the chemical synthesis system.

[0026] Please refer to Figure 1The device 10 for preparing formic acid by electro-catalysis in a pressurized water reactor environment comprises a pressurized water reactor first loop system 100, a circulating water second loop system 200 and an electrolytic formic acid preparation device 300. The device makes full use of the high-grade heat energy carried by the first loop coolant of the pressurized water reactor, heats the circulating water in the second loop through the steam generator 130 and generates steam to drive the steam turbine 210 to generate electricity, thereby providing a stable power source for the chemical reaction process of the electrolytic formic acid preparation.

[0027] Specifically, the pressurized water reactor first loop system 100 comprises a reactor 110, a pressurizer 120, a steam generator 130 and a coolant pump 140. The reactor 110, the pressurizer 120 and the steam generator 130 are connected in sequence to form a first loop, and the coolant pump 140 is used to drive the circulation of the coolant in the first loop. The coolant is used to transport the heat generated by the reactor 110 to the steam generator 130 for heat exchange with the circulating water in the second loop system 200. As a key heat exchange interface, the steam generator 130 transfers heat from the first loop to the circulating water in the second loop system 200 through an inter-wall heat exchanger, thereby converting low-temperature cooling water into high-temperature steam for driving power generation.

[0028] The circulating water second loop system 200 comprises a steam turbine 210, a condenser 220, a cooling water source 230, a steam generator 130 and an electrolytic formic acid preparation device 300. The steam turbine 210 has an inlet 211 and two outlets 212. The inlet 211 of the steam turbine 210 is connected to the steam generator 130 to receive high-temperature steam. The spent steam discharged from the first outlet is used to drive the generator 400 to generate electricity, while the spent steam discharged from the second outlet 212 no longer enters the condenser 220 but is guided to the electrolytic formic acid preparation device 300 for heat supply and insulation. The condenser 220 is connected to the other outlet of the steam turbine 210 to condense the remaining spent steam that has completed work into liquid water. The condensed water is returned to the cooling water source 230, part of which is returned to the second loop for circulation, and the other part of the liquid water is transported to the electrolytic formic acid preparation device 300 as a reaction raw material to participate in the electro-catalytic synthesis of formic acid reaction. A first feed water pump 201 is provided in the second loop to provide power for the circulating water flow; a second feed water pump 202 is provided on the pipeline between the cooling water source 230 and the electrolytic formic acid preparation device 300 to accurately transport the cooling water to the reaction system.

[0029] The temperature of the exhaust steam drawn from the steam turbine 210 is maintained in the range of 38-62°C, which belongs to low-grade heat energy and is not enough to continue to drive the steam turbine generator, but just meets the demand of the electrolytic formic acid reaction system for the insulation temperature. The exhaust steam can be effectively heated in the following two ways: 1. Direct heating, that is, the exhaust steam is introduced into the closed space containing the electrolytic formic acid device 300, and the overall environment is heated by air convection and heat radiation to maintain the stable operation temperature of the equipment; 2. Jacket heat exchange, a jacket structure is arranged outside the electrolytic reactor, and the exhaust steam flows in the jacket to provide uniform and controllable heat source for the reaction system through the wall heat transfer. The above two ways can be flexibly selected or combined according to the actual working condition to ensure that the reaction temperature is in the optimal interval and improve the electrolysis efficiency and product selectivity. Through the cascade utilization of the low-grade exhaust steam discharged from the steam turbine, the exhaust steam is used for the insulation of the electrolytic device, which reduces the heat load of the condenser 220 and the cooling water consumption, and improves the thermal efficiency of the entire nuclear power unit; the use of waste heat to maintain the stability of the electrolytic reaction temperature reduces the external electric heating demand, thereby reducing the auxiliary energy consumption of the electrolytic formic acid device 300.

[0030] The pressurized water reactor environment electrolytic preparation of formic acid device 10 is equipped with an intelligent scheduling controller, the input end of the controller is connected with the generator 400, and the output end is connected with the electrolytic formic acid device 300 and the power system 600 respectively. The controller receives the power demand signals of the electrolytic device and the power grid in real time, and dynamically allocates and schedules the power generated by the generator according to the signals. In order to realize flexible power scheduling, the controller is configured with a first switch and a second switch: the first switch is arranged on the line between the generator and the power system, and controls the on-off thereof; the second switch is arranged on the line between the generator and the electrolytic formic acid device, and realizes independent control of the branch.

[0031] The alternating current output by the generator is converted into direct current by the rectifier, and the output end thereof is further connected with a constant current power supply module to ensure the stability of the current delivered to the electrolytic device. The electrolytic formic acid device 300 includes a reaction tank, an anode, a diaphragm, a cathode, an electrolyte and a carbon dioxide inlet device. The output end of the constant current power supply module is connected with the positive and negative electrodes of the electrolytic device to provide constant current direct current for the electrolytic device. In order to further optimize the reaction conditions, the device is also equipped with an electrolyte circulating device, which strengthens the mass transfer at the reaction interface by controlling the electrolyte flow rate, promotes the replenishment of carbon dioxide reactants and the removal of formic acid products, thereby improving the reaction rate and current efficiency, while maintaining the uniformity of the system temperature and concentration, and ensuring continuous and stable operation.

[0032] In terms of operation strategy, the system prioritizes the power supply demand of the power system 600. Since the output power of the reactor 110 is basically constant, and the grid load fluctuates periodically, the formic acid electrolysis device 300 as a flexible load can dynamically adjust the input power according to the power supply situation: reduce the electrolysis load during the peak period of grid electricity consumption, and reduce the formic acid production; during the valley period of the grid, the excess power is distributed to the formic acid electrolysis device 300 to improve the formic acid production capacity, so as to realize efficient consumption of nuclear energy output and balance of system load. This collaborative control strategy brings multiple comprehensive benefits. First, by matching the grid demand and electrolysis production capacity in real time, the input power of the electrolysis device is adaptively adjusted in a wide range, effectively stabilizing the grid fluctuation, enhancing the stability of the nuclear power unit operation, avoiding frequent peak shaving, and improving the safety and economy of the reactor operation. Second, during the valley period of the grid, the excess power is converted into high-value-added formic acid products, which not only improves the comprehensive utilization efficiency of nuclear energy, but also realizes the dual conversion and storage of energy and matter. In addition, this strategy significantly reduces the risk of power abandonment and improves the flexibility and low-carbon benefits of the energy system.

[0033] The embodiment of the present application also provides a process method for electrocatalytic preparation of formic acid, which utilizes the above-mentioned formic acid electrolysis device 10 under the pressure water reactor environment to carry out reaction. During the reaction of electrocatalytic preparation of formic acid, the electrolyte circulates at a flow rate of 2-5 mL / min.

[0034] Specifically, within this flow rate range, the carbon dioxide gas-liquid mass transfer and product desorption on the electrode surface can be effectively strengthened, the reaction rate and formic acid selectivity can be improved, and the management of reaction heat and the system temperature balance can be facilitated, thereby avoiding local overheating or concentration polarization, and thus significantly improving the stability, energy efficiency and product yield of formic acid synthesis under the continuous operation environment supported by nuclear energy.

[0035] Further, the reduction potential applied by the formic acid electrolysis device 300 during the reaction of electrocatalytic preparation of formic acid is 1-5 V.

[0036] Specifically, this original potential range can ensure the efficient reduction of carbon dioxide to formic acid in the chemical reaction, and more importantly, can effectively inhibit the competitive side reactions such as hydrogen evolution, thereby improving the reaction selectivity and Faraday efficiency. In addition, this reduction potential range also helps to reduce the system overpotential, reduce energy consumption, and protect the cathode catalyst from deactivation caused by strong reduction conditions, further improving the economy and long-term operation stability of the reaction process. Please refer to Figure 2 and Figure 3 When the reduction voltage of the formic acid electrocatalytic preparation chemical reaction is in the range of 1-5 V, the yield of formic acid can reach 65-88 mg / (cm 2 ·h), and the corresponding energy efficiency is 35%-45%.

[0037] The working principle of the device 10 for preparing formic acid by electrocatalysis in a pressurized water reactor environment is as follows: The heat energy generated by the reactor 110 is transmitted to the circulating water second loop system 200 through the steam generator 130, and the steam generated by the steam generator 130 drives the turbine generator 400 group to generate alternating current energy; the electric energy is converted into direct current with high current stability through the rectifier and the stabilized power supply module, and is transmitted to the electrolytic formic acid device 300. At the same time, the low-temperature exhaust steam discharged from the steam turbine 210 is introduced into the electrolytic device to provide a heat preservation source. The electrolytic formic acid device 300 operates at a constant current and a suitable temperature, and the carbon dioxide introduced is reduced to formic acid on the cathode surface, and the anode is oxidized to generate oxygen. The electrolyte circulation system is integrated in the device, and the electrolyte is continuously circulated at a flow rate of 2-5 mL / min to strengthen the mass transfer process and maintain the uniformity and stability of the reaction system. The intelligent scheduling controller monitors the load demand of the power system 600 and the electrolytic formic acid device 300 in real time, and dynamically allocates the power generation: preferentially guarantees the power supply of the power system 600, and during the low load period of the power system 600, the surplus power is allocated to the electrolytic formic acid device 300, so as to realize the efficient consumption of nuclear energy output in the whole period, the flexible auxiliary peak shaving of the power system 600 and the continuous and stable production of formic acid products, and finally greatly improve the comprehensive energy efficiency of nuclear energy.

[0038] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A device for electrocatalytic preparation of formic acid in a pressurized water reactor environment, characterized by, The application relates to a pressurized water reactor first loop system (100), a circulating water second loop system (200) and an electrolytic formic acid device (300). The pressurized water reactor first loop system (100) comprises a reactor (110), a pressurizer (120), a steam generator (130) and a coolant pump (140), the reactor (110), the pressurizer (120) and the steam generator (130) are sequentially connected to form a first loop, the coolant pump (140) is used for driving the circulation of a coolant in the first loop, the coolant is used for transporting heat generated by the reactor (110) to the steam generator (130), and then performing heat exchange with a circulating water second loop system (200), and the steam generator (130) is connected with the circulating water second loop system (200) and the electrolytic formic acid device (300). The circulating water second loop system (200) comprises a steam turbine (210), a condenser (220), a cooling water source (230) and the steam generator (130), the steam turbine (210), the condenser (220), the cooling water source (230) and the steam generator (130) are sequentially connected to form a second loop, cooling water circulates and flows in the second loop, and heat exchange is performed between the steam generator (130) and the coolant. The electrolytic formic acid device (300) is connected with the steam turbine (210) through a generator (400).

2. The pressurized water reactor in-situ electrocatalytic formic acid production device according to claim 1, characterized in that, The steam turbine (210) has an inlet (211) and an outlet (212), the inlet (211) is connected with the steam generator (130), and spent steam discharged from the outlet (212) is used for heating the electrolytic formic acid device (300).

3. The pressurized water reactor in-situ electrocatalytic formic acid production device according to claim 1, characterized in that, The pressurized water reactor environment electrolytic formic acid device (10) further comprises an intelligent scheduling controller, an input end of the intelligent scheduling controller is connected with the generator (400), an output end of the intelligent scheduling controller is connected with the electrolytic formic acid device (300) and an electric power system (600), is electrically connected with the electric power system (600), is used for receiving power consumption demand signals of the electrolytic formic acid device (300) and the electric power system (600), and based on the demand signals, real-time distribution and power scheduling are performed on electric energy generated by the generator (400).

4. The pressurized water reactor in-situ electrocatalytic formic acid production device according to claim 3, characterized in that, The intelligent scheduling controller further comprises a first switch and a second switch, the first switch is located on a line of the generator (400) and the electric power system (600), is used for controlling the on-off of the line of the generator (400) and the electric power system (600), and the second switch is located on a line of the generator (400) and the electrolytic formic acid device (300), is used for controlling the on-off of the line of the generator (400) and the electrolytic formic acid device (300).

5. The pressurized water reactor in-situ electrocatalytic formic acid production apparatus according to claim 1, wherein, The device (10) for preparing formic acid by electrocatalysis under the environment of pressurized water reactor further comprises a rectifier for converting alternating current output by the generator (400) into direct current, one end of the rectifier being electrically connected with the generator (400) and the other end being electrically connected with the device (300) for preparing formic acid by electrolysis.

6. The pressurized water reactor in-situ electrocatalytic formic acid production apparatus according to claim 5, characterized in that, The device (10) for preparing formic acid by electrocatalysis under the environment of pressurized water reactor further comprises a stabilized power supply module, an input end of the stabilized power supply module being connected with an output end of the rectifier for converting direct current output by the rectifier into direct current with stable current.

7. The pressurized water reactor in-situ electrocatalytic formic acid production device according to claim 6, characterized in that, The device (300) for preparing formic acid by electrolysis comprises a reaction tank, an anode, a diaphragm, a cathode, an electrolyte and a device for introducing carbon dioxide, the device for introducing carbon dioxide being used for introducing carbon dioxide into the reaction tank, an output end of the stabilized power supply module being connected with positive and negative electrodes of the device (300) for preparing formic acid by electrolysis for providing stable direct current for electrolysis reaction.

8. The pressurized water reactor in-situ electrocatalytic formic acid production device according to claim 7, characterized in that, The device (300) for preparing formic acid by electrolysis further comprises an electrolyte circulating device for driving the electrolyte to circulate in the reaction tank at a set flow rate.

9. A process for the electrocatalytic production of formic acid, characterized in that The device (10) for preparing formic acid by electrocatalysis under the environment of pressurized water reactor is used for reaction, and in the reaction process of preparing formic acid by electrocatalysis, the electrolyte circulates at a flow rate of 2-5 mL / min.

10. The process for the electrocatalytic production of formic acid according to claim 9, characterized in that, The device (300) for preparing formic acid by electrolysis applies a reduction potential of 1-5 V in the reaction process of preparing formic acid by electrocatalysis.

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