An electrochemical nitrogen cycle simulation system and a nitrogen cycle method

Abstract

The present invention discloses an electrochemical nitrogen cycle simulation system and a nitrogen cycle method. The electrochemical nitrogen cycle simulation system specifically includes: an electrolysis unit, an ammonia synthesis unit, a fuel cell and an ecological unit that are interconnected in pairs; the ecological unit is used to store or consume ammonia provided by the ammonia synthesis unit, and provide part of the ammonia to the electrolysis unit and the fuel cell, decompose the other part of the ammonia to generate a synthetic ammonia raw material, and provide the synthetic ammonia raw material to the ammonia synthesis unit. The present invention covers the ecological unit as the basis of the nitrogen cycle system, provides an electrochemical nitrogen cycle simulation system, realizes a comprehensive energy cycle solution that uses ammonia as a nitrogen cycle carrier and accommodates renewable energy, and can effectively promote the development of nitrogen cycle scene applications.

Description

Technical Field

[0001] The invention belongs to the technical field of energy technology recycling, and specifically relates to an electrochemical nitrogen cycle simulation system and a nitrogen cycle method. Background Art

[0002] Nitrogen and its compounds are widely used in production and life, and the mutual transformation between nitrogen and its compounds constitutes the nitrogen cycle of the global chemical industry and natural ecosystems. The nitrogen cycle generally includes nitrogen fixation, ammoniation, nitrification, denitrification, and ammonia deposition and release.

[0003] As an important carrier in the nitrogen cycle, ammonia (NH3) is not only a core component in fertilizers, pharmaceuticals and fine chemicals, but also an ideal carbon-free fuel. It occupies an important position in heavy industry, shipping, aviation and heavy transportation.

[0004] Compared with other high-density hydrogen storage media (such as methane and methanol), ammonia has a complete manufacturing, storage and transportation system. The traditional Haber-Bosch process has achieved large-scale industrial production of ammonia, but the process needs to be carried out under extremely harsh conditions (high temperature and high pressure), and is inevitably accompanied by high energy consumption and high CO2 emissions. As a key link in breaking through the bottleneck of hydrogen energy industry development, it is imperative to explore green and sustainable synthetic ammonia technology in the face of the "dual carbon" strategy, while also overcoming the application challenges of high hydrogen storage and transportation costs, low energy density, and poor safety.

[0005] At present, there are studies on nitrogen cycle systems to achieve green and sustainable ammonia synthesis and efficient application of ammonia. For example, patent CN114725428A discloses a zero-carbon emission solid oxide fuel cell and renewable energy combined power generation system with ammonia as carrier, including an ammonia storage device, an ammonia cracking device, a separator, a nitrogen storage device, a heat exchanger I, an automatic three-way valve, a water remover, a solid oxide fuel cell, an air compressor, an oxygen storage device, a valve, a heat exchanger II, a storage battery, a user end, a combustion chamber, a steam generator, an electrochemical ammonia synthesis device, and a renewable energy power generation system; when the solid oxide fuel cell and renewable energy combined power generation system performs a fuel cell cycle, the ammonia in the ammonia storage device is used as fuel, and the solid oxide fuel cell is used as a power generation device to supply power to the user end and the storage battery; when performing a renewable energy cycle, renewable energy, air and water are used to supply power to the user end and the storage battery and prepare ammonia.

[0006] In addition, there are also studies on nitrogen cycle systems from the perspective of simulation. For example, patent CN118114497A provides a modeling method for hydrogen and ammonia energy storage systems based on renewable energy power generation, which mainly includes building a renewable energy power generation model, a hydrogen and ammonia energy storage system model, formulating constraints, and establishing a system simulation model. In terms of renewable energy power generation systems, the modeling methods of wind power generation and solar cell power generation are introduced in detail. For energy storage systems, a detailed description of hydrogen and ammonia energy storage systems is given, including modeling methods for PEM electrolysis cells and synthetic ammonia systems. After the system model is established, the constraints of each device and the constraints of the system operation are constructed respectively, and then the comprehensive energy system simulation model is systematically simulated and calculated to obtain key parameters such as the power generation or consumption of each component, the system hydrogen production and ammonia production. Accurate modeling and performance evaluation of the entire hydrogen and ammonia energy storage system are achieved, and the application of this method helps to optimize system performance and improve operational stability.

[0007] However, whether it is the research on nitrogen cycle devices or the research on renewable energy power generation systems through modeling and simulation, the current technology for realizing nitrogen cycle and ammonia application involving synthetic ammonia processes still focuses on ammonia synthesis or energy storage cycles in pure chemistry or pure power industries, and does not consider incorporating natural ecological links into the nitrogen cycle.

[0008] Therefore, how to include the natural ecological module in the nitrogen cycle, realize ammonia as the nitrogen cycle carrier, consider the electrochemical laws of ammonia synthesis and decomposition in the nitrogen cycle, and provide a comprehensive energy cycle plan that accommodates renewable energy is an urgent problem to be solved by technical personnel in this field. Summary of the invention

[0009] In view of the defects existing in the above-mentioned prior art, the present invention discloses an electrochemical nitrogen cycle simulation system and a nitrogen cycle method. The electrochemical nitrogen cycle simulation system specifically includes: an electrolysis unit, an ammonia synthesis unit, a fuel cell and an ecological unit that are interconnected in pairs; the ecological unit is used to store or consume ammonia provided by the ammonia synthesis unit, and provide part of the ammonia to the electrolysis unit and the fuel cell, decompose the other part of the ammonia to generate a synthetic ammonia raw material, and provide the synthetic ammonia raw material to the ammonia synthesis unit. The present invention covers the ecological unit as the basis of the nitrogen cycle system, provides an electrochemical nitrogen cycle simulation system, realizes a comprehensive energy cycle solution that uses ammonia as a nitrogen cycle carrier and accommodates renewable energy, and can effectively promote the development of nitrogen cycle scenario applications.

[0010] In a first aspect, the present invention provides an electrochemical nitrogen cycle simulation system, specifically comprising:

[0011] Electrolysis units, ammonia synthesis units, fuel cells and ecological units interconnected in pairs;

[0012] An electrolysis unit, used for electrolyzing ammonia provided by the ecological unit and the ammonia synthesis unit to generate synthetic ammonia raw materials, and providing the synthetic ammonia raw materials to the ammonia synthesis unit and the fuel cell respectively;

[0013] The ecological unit is used to store or consume ammonia provided by the ammonia synthesis unit, and provide part of the ammonia to the electrolysis unit and the fuel cell, decompose the other part of the ammonia to generate a synthetic ammonia raw material, and provide the synthetic ammonia raw material to the ammonia synthesis unit;

[0014] An ammonia synthesis unit is used to electrochemically synthesize ammonia from the synthetic ammonia raw materials provided by the electrolysis unit, the ecological unit and the fuel cell, and provide the synthesized ammonia to the ecological unit, the fuel cell and the electrolysis unit;

[0015] The fuel cell is used to convert chemical energy of ammonia or synthetic ammonia raw materials provided by the electrolysis unit, the ecological unit and the ammonia synthesis unit into electrical energy, supply power to the electrolysis unit and the ammonia synthesis unit, and provide synthetic ammonia raw materials to the ammonia synthesis unit.

[0016] Furthermore, the cathode reaction chamber outlet and the anode reaction chamber outlet of the electrolysis unit are connected to the cathode gas collection tank inlet and the anode gas-liquid separator inlet, respectively;

[0017] The outlet end of the cathode gas collection tank is connected to the first humidification tank, and the first humidification tank is connected to the inlet end of the fuel cell to provide hydrogen and water to the fuel cell;

[0018] The outlet end of the anode gas-liquid separator is respectively connected to the liquid collecting tank and the first anode gas collecting tank. The liquid collecting tank is connected to the ammonia synthesis unit via the first peristaltic pump to supply the nitrate-containing raw material to the ammonia synthesis unit. The first anode gas collecting tank is connected to the ammonia synthesis unit via the first pneumatic valve to supply the nitrogen-containing gas to the ammonia synthesis unit.

[0019] Furthermore, the outlet end of the ammonia synthesis unit is connected to an ammonia collecting tank, and the ammonia collecting tank is respectively connected to the ecological unit, the fuel cell and the electrolysis unit via a second peristaltic pump, and provides ammonia to the ecological unit, the fuel cell and the electrolysis unit.

[0020] Furthermore, the outlet end of the fuel cell is connected to a second anode gas collecting tank, and the second anode gas collecting tank is connected to the ammonia synthesis unit via a second pneumatic valve to supply nitrogen-containing gas to the ammonia synthesis unit.

[0021] Furthermore, it also includes a power supply unit and a gas processing unit;

[0022] The power supply unit is used to supply power to the ammonia synthesis unit and the electrolysis unit;

[0023] The gas processing unit is connected to the fuel cell and the ammonia synthesis unit respectively to obtain synthetic ammonia raw materials and provide them to the fuel cell and the ammonia synthesis unit.

[0024] Further, the gas processing unit includes an air separation device and a second humidification tank;

[0025] The outlet end of the air separation device is respectively connected to the ammonia synthesis unit and the second humidification tank to provide nitrogen-containing gas to the ammonia synthesis unit, and to provide oxygen and water to the fuel cell through the second humidification tank.

[0026] Further, the ecological unit includes a simulated growth device and a metabolite collection device connected to the outlet end of the simulated growth device;

[0027] The simulated growth device is connected to the second peristaltic pump, stores or consumes ammonia provided by the ammonia synthesis unit via the second peristaltic pump, and provides ammonia to the electrolysis unit and the fuel cell via the second peristaltic pump;

[0028] The outlet end of the metabolite collection device is connected to the ammonia synthesis unit to provide the synthetic ammonia raw material to the ammonia synthesis unit.

[0029] Furthermore, the simulated growth unit stores or consumes ammonia provided by the ammonia synthesis unit via the second peristaltic pump, and provides ammonia to the electrolysis unit and the fuel cell via the second peristaltic pump, which is specifically expressed as follows:

[0030]

[0031] Among them, ΔM is the amount of N substance that consumes nutrients in the simulated growth unit, M0 is the amount of N substance that is the benchmark for growth balance in the simulated growth unit, α1 is the conversion rate of the ammonia synthesis unit, α0 is the minimum conversion rate of N in the simulated growth unit, m1 is the amount of N substance provided by the gas processing unit to the ammonia synthesis unit, m5 is the amount of N substance provided by the electrolysis unit to the ammonia synthesis unit, m6 is the amount of N substance provided by the fuel cell to the ammonia synthesis unit, m8 is the amount of N substance provided by the simulated growth unit to the fuel cell, and m9 is the amount of N substance provided by the simulated growth unit to the electrolysis unit.

[0032] Furthermore, the electrochemical nitrogen cycle simulation system also includes a heat exchange unit, which is connected to the electrolysis unit, the ammonia synthesis unit and the fuel cell, and is used to balance the heat of the electrolysis unit, the ammonia synthesis unit and the fuel cell, which is specifically expressed as:

[0033] Q1≥(Q2+((Q 31 -Q 32 ))

[0034] Among them, Q1 is the heat dissipated by the fuel cell, Q2 is the heat required by the electrolysis unit, and Q 31 is the reaction heat required for the ammonia synthesis unit, Q 32 It is the energy released by ammonia synthesis in the ammonia synthesis unit.

[0035] Furthermore, the heat exchange unit is used to balance the heat of the electrolysis unit, the ammonia synthesis unit and the fuel cell, and specifically includes:

[0036] Obtain the reaction heat, ammonia synthesis reaction amount and reaction enthalpy change required by the ammonia synthesis unit, and give the heat required by the ammonia synthesis unit;

[0037] Based on the analysis of the ammonia electrolysis path in the electrolysis unit, combined with multiple electrolysis parameter combinations and the historical probability data distribution of the ammonia electrolysis path under each electrolysis parameter combination, the proportion weight of each ammonia electrolysis path is given, which is specifically expressed as:

[0038]

[0039] Wherein, x is the proportional weight of the first ammonia electrolysis path, y is the proportional weight of the second ammonia electrolysis path, z is the proportional weight of the third ammonia electrolysis path, w is the proportional weight of the fourth ammonia electrolysis path, i is the number of the electrolysis parameter combination, n is the total number of electrolysis parameter combinations, β i is the occurrence probability of the i electrolysis parameter combination, j,x is the number of the probability of the first path of ammonia electrolysis, m x is the total number of probability cases of the first path of ammonia electrolysis, γ j,x is the probability value of the first path of ammonia electrolysis under j, x, P j,x For the corresponding γ j,x The ratio value of j,x is the number of the probability of occurrence of the first path of ammonia electrolysis, m y is the total number of probability cases of the second path of ammonia electrolysis, γ j,y is the probability value of the occurrence probability of the second path of ammonia electrolysis under j, y, P j,y For the corresponding γ j,y The ratio of j, y is the number of the probability of the second path of ammonia electrolysis, m z is the total number of probability cases of the third path of ammonia electrolysis, γ j,z is the probability value of the occurrence probability of the third path of ammonia electrolysis under j, z, P j,z For the corresponding γ j,z The ratio of j, z is the number of the probability of occurrence of the third path of ammonia electrolysis, m w is the total number of probability cases of the fourth path of ammonia electrolysis, γ j,w is the probability value of the fourth path of ammonia electrolysis under j, w, P j,w For the corresponding γ j,w The ratio value of

[0040] Based on the proportional weights of each ammonia electrolysis path, the heat required by the electrolysis unit is determined, which is specifically expressed as:

[0041]

[0042] Among them, m x is the amount of ammonia in the first path of ammonia electrolysis, m y is the amount of ammonia in the second path of ammonia electrolysis, m z is the amount of ammonia in the third path of ammonia electrolysis, m w is the amount of ammonia substance in the fourth ammonia electrolysis path, ΔH1 is the enthalpy variable of the first ammonia electrolysis path, ΔH2 is the enthalpy variable of the second ammonia electrolysis path, ΔH3 is the enthalpy variable of the third ammonia electrolysis path, and ΔH4 is the enthalpy variable of the fourth ammonia electrolysis path;

[0043] The heat supply of the fuel cell is determined based on the heat required by the ammonia synthesis unit and the heat required by the electrolysis unit, combined with the conversion efficiency of the heat exchange unit.

[0044] In a second aspect, the present invention further provides an electrochemical nitrogen cycle simulation method, using the electrochemical nitrogen cycle simulation system as described above, specifically comprising the following steps:

[0045] Electrolyzing ammonia provided by the ecological unit and the ammonia synthesis unit through the electrolysis unit to generate synthetic ammonia raw materials, and providing the synthetic ammonia raw materials to the ammonia synthesis unit and the fuel cell respectively;

[0046] Based on the ecological unit, the ammonia provided by the ammonia synthesis unit is stored or consumed, and part of the ammonia is provided to the electrolysis unit and the fuel cell, and the other part of the ammonia is decomposed to generate a synthetic ammonia raw material, and the synthetic ammonia raw material is provided to the ammonia synthesis unit;

[0047] In the ammonia synthesis unit, ammonia is synthesized electrochemically from the synthetic ammonia raw materials provided by the electrolysis unit, the ecological unit and the fuel cell, and the synthesized ammonia is provided to the ecological unit, the fuel cell and the electrolysis unit;

[0048] In the fuel cell, chemical energy of ammonia or synthetic ammonia raw materials provided by the electrolysis unit, the ecological unit and the ammonia synthesis unit is converted into electrical energy, and power is supplied to the electrolysis unit and the ammonia synthesis unit, and synthetic ammonia raw materials are provided to the ammonia synthesis unit.

[0049] The present invention provides an electrochemical nitrogen cycle simulation system and a nitrogen cycle method, which have at least the following beneficial effects:

[0050] (1) The present invention takes the ecological unit as the basis of the nitrogen cycle system, provides an electrochemical nitrogen cycle simulation system, realizes a comprehensive energy cycle solution with ammonia as the nitrogen cycle carrier and accommodates renewable energy, and can effectively promote the development of nitrogen cycle scenario applications.

[0051] (2) The present invention uses the dynamic changes of nutrient storage and consumption in ecological units as the connection point and the balance and stability of the entire electrochemical nitrogen cycle system as the goal, thereby realizing the determination of the interactive relationship between components and energy between various units.

[0052] (3) The present invention takes into account the complexity of the ammonia electrolysis process, and through the sorting of historical test data under various combinations of parameters and conditions, combined with probability statistical analysis, an accurate prediction simulation of the heat required in the ammonia electrolysis process is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 A schematic diagram of the architecture of an electrochemical nitrogen cycle simulation system provided by the present invention;

[0054] Figure 2 A schematic structural diagram of an electrochemical nitrogen cycle simulation system according to a first embodiment of the present invention;

[0055] Figure 3 A schematic structural diagram of an electrochemical nitrogen cycle simulation system according to a second embodiment of the present invention;

[0056] Figure 4 A schematic diagram of a heat exchange structure in an electrochemical nitrogen cycle simulation system according to a certain embodiment of the present invention;

[0057] Figure 5 A schematic flow chart of an electrochemical nitrogen cycle simulation method provided by the present invention.

[0058] Description of reference numerals:

[0059] 1-electrolysis unit, 11-cathode reaction chamber, 12-anode reaction chamber, 13-cathode gas collection tank, 14-anode gas-liquid separator, 15-first humidification tank, 16-liquid collection tank, 17-first anode gas collection tank, 18-first peristaltic pump, 19-first pneumatic valve, 2-ammonia synthesis unit, 21-ammonia collection tank, 22-second peristaltic pump, 3-fuel cell, 31-second anode gas collection tank, 32-second pneumatic valve, 4-ecological unit, 41-simulated growth equipment, 42-metabolite collection equipment, 5-power supply unit, 6-gas processing unit, 61-air separation equipment, 62-second humidification tank. DETAILED DESCRIPTION

[0060] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0062] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0063] The current technologies related to the nitrogen cycle and ammonia application in the ammonia synthesis process, whether it is the research on nitrogen cycle devices or the research on renewable energy power generation systems through modeling and simulation, focus on cycles in pure chemical industry or pure power industry.

[0064] The recycling in pure chemical industry or pure power industry ignores the important role of ammonia in the natural ecological process.

[0065] For the nitrogen cycle covering the natural ecological links, it is necessary to consider the electrochemical laws of ammonia and nitrogen in the cycle process, and to realize ammonia as the nitrogen cycle carrier. By simulating the electrochemical nitrogen cycle, the ammonia synthesis unit, ammonia electrolysis unit and ammonia fuel cell can be coupled, focusing on the changes in the transfer of nitrogen / ammonia components and the exchange of energy / heat in the nitrogen cycle process, and giving the laws of nitrogen and energy recycling.

[0066] The development of the electrochemical nitrogen cycle simulation system can be achieved through various types of software carriers (two-dimensional / three-dimensional simulation models), such as Plant Simulation, Ansys fluent abaqus, FlexSim, etc. The selection can be made according to the needs of the actual application scenario, and no specific limitation is made here.

[0067] like Figure 1 As shown, the present invention provides an electrochemical nitrogen cycle simulation system, which specifically includes:

[0068] An electrolysis unit 1, an ammonia synthesis unit 2, a fuel cell 3 and an ecological unit 4 which are interconnected in pairs;

[0069] The electrolysis unit 1 is used to electrolyze the ammonia provided by the ecological unit 4 and the ammonia synthesis unit 2 to generate a synthetic ammonia raw material, and provide the synthetic ammonia raw material to the ammonia synthesis unit 2 and the fuel cell 3 respectively;

[0070] The ecological unit 4 is used to store or consume the ammonia provided by the ammonia synthesis unit 2, and provide part of the ammonia to the electrolysis unit 1 and the fuel cell 3, decompose the other part of the ammonia to generate a synthetic ammonia raw material, and provide the synthetic ammonia raw material to the ammonia synthesis unit 2;

[0071] The ammonia synthesis unit 2 is used to electrochemically synthesize ammonia from the synthetic ammonia raw materials provided by the electrolysis unit 1, the ecological unit 4 and the fuel cell 2, and provide the synthesized ammonia to the ecological unit 4, the fuel cell 3 and the electrolysis unit 1;

[0072] The fuel cell 4 is used to convert chemical energy of ammonia or synthetic ammonia raw materials provided by the electrolysis unit 1, the ecological unit 4 and the ammonia synthesis unit 2 into electrical energy, supply power to the electrolysis unit 1 and the ammonia synthesis unit 2, and provide synthetic ammonia raw materials to the ammonia synthesis unit.

[0073] The ecological unit is used to simulate a space station or a closed space environment. There are animals / plants in the ecological unit, and the nutrients (such as ammonia fertilizer) required for the animals / plants to maintain growth balance are provided by the ammonia synthesis unit. When the animals / plants are in a rapid growth and expansion stage, the ammonia synthesis unit supplies excessive ammonia fertilizer, and when the animals / plants are in a slow growth, or even reduced production or decline, the ammonia synthesis unit supplies insufficient ammonia fertilizer. Of course, the ecological unit can also serve as a transition station for ammonia fertilizer, providing the ammonia fertilizer supplied by the ammonia synthesis unit to the electrolysis unit and the fuel unit.

[0074] For the electrolysis unit, ammonia is electrolyzed under the drive of electric energy to generate synthetic ammonia raw materials containing N and H2. The ammonia raw materials containing N include N2, NO and NO x - , NO x - Including NO2 - 、NO3 - In the ammonia synthesis unit, ammonia is synthesized by electrochemical techniques, such as electrochemical nitrogen reduction (NRR), NO reduction (NORR) and NO3 - / NO2 - Reduction (NtrRR), N2 / NO / NO x - In the ammonia synthesis unit, in addition to N2 as a nitrogen source, nitrogen species that are harmful to the environment and more active than N2 (such as NO, NO3 - / NO2 -) is also considered to be a powerful nitrogen source for producing ammonia under ambient conditions, thereby alleviating environmental pollution and future energy problems in a green and sustainable way.

[0075] As a zero-carbon electrochemical energy conversion device, fuel cells use ammonia as fuel to drive work in the nitrogen cycle system and provide zero-carbon emission electricity. The organic combination of electrolysis units, fuel cells and ammonia synthesis units can build a self-driven nitrogen cycle system with rich application scenarios, which can not only directly or indirectly reduce carbon emissions and hydrogen production energy consumption in the synthetic nitrogen process, but also benefit the energy conservation and emission reduction of the entire integrated energy system and the development and utilization of clean energy.

[0076] The present invention covers the natural ecological module in the nitrogen cycle, realizes ammonia as the nitrogen cycle carrier, considers the electrochemical laws of ammonia synthesis and decomposition in the nitrogen cycle, and provides a comprehensive energy cycle plan that accommodates renewable energy.

[0077] The connection between the various units can be realized through the following structural methods:

[0078] like Figure 2-3 As shown, the outlet end of the cathode reaction chamber 11 and the outlet end of the anode reaction chamber 12 of the electrolysis unit 1 are connected to the inlet end of the cathode gas collection tank 13 and the inlet end of the anode gas-liquid separator 14 respectively;

[0079] The outlet end of the cathode gas collection tank 13 is connected to the first humidification tank 15, and the first humidification tank 15 is connected to the inlet end of the fuel cell 3 to provide hydrogen and water to the fuel cell 3;

[0080] The outlet end of the anode gas-liquid separator 14 is connected to the liquid collecting tank 16 and the first anode gas collecting tank 17 respectively. The liquid collecting tank 16 is connected to the ammonia synthesis unit 2 via the first peristaltic pump 18 to supply the nitrate-containing raw material to the ammonia synthesis unit 2. The first anode gas collecting tank 17 is connected to the ammonia synthesis unit 2 via the first pneumatic valve 19 to supply the nitrogen-containing gas to the ammonia synthesis unit 2.

[0081] The outlet end of the ammonia synthesis unit 2 is connected to the ammonia collection tank 21, and the ammonia collection tank 21 is connected to the ecological unit 4, the fuel cell 3 and the electrolysis unit 1 respectively through the second peristaltic pump 22, and provides ammonia to the ecological unit 4, the fuel cell 3 and the electrolysis unit 1.

[0082] The outlet end of the fuel cell 3 is connected to the second anode gas collecting tank 31 , and the second anode gas collecting tank 31 is connected to the ammonia synthesis unit 2 via the second pneumatic valve 32 to supply the nitrogen-containing gas to the ammonia synthesis unit 2 .

[0083] In addition, in order to ensure the power supply and the supplement of external components in the electrochemical nitrogen circulation system, the electrochemical nitrogen circulation system also includes a power supply unit 5 and a gas processing unit 6;

[0084] The power supply unit 5 is used to supply power to the ammonia synthesis unit 2 and the electrolysis unit 1;

[0085] The gas processing unit 6 is connected to the fuel cell 3 and the ammonia synthesis unit 2 respectively, and is used to obtain synthetic ammonia raw materials and provide them to the fuel cell 3 and the ammonia synthesis unit 2.

[0086] The gas processing unit 6 includes an air separation device 61 and a second humidification tank 62;

[0087] The outlet end of the air separation device 61 is connected to the ammonia synthesis unit 2 and the second humidification tank 62 respectively, to provide nitrogen-containing gas to the ammonia synthesis unit 2 , and to provide oxygen and water to the fuel cell 3 via the second humidification tank 62 .

[0088] In addition to the fuel cell, the electrochemical nitrogen cycle system also includes a power supply unit. The power supply unit can be powered by solar energy or wind energy, etc., and is set according to different application scenarios. No specific limitation is made here.

[0089] The gas processing unit can extract N2 and O2 from the air and is connected to the fuel cell and ammonia synthesis unit to provide raw materials.

[0090] The ecological unit 4 includes a simulated growth device 41 and a metabolite collection device 42 connected to the outlet of the simulated growth device;

[0091] The simulated growth device 41 is connected to the second peristaltic pump 22, stores or consumes ammonia provided by the ammonia synthesis unit 2 via the second peristaltic pump 22, and provides ammonia to the electrolysis unit 1 and the fuel cell 3 via the second peristaltic pump 22;

[0092] The outlet end of the metabolite collection device 42 is connected to the ammonia synthesis unit 2 to provide the synthetic ammonia raw material to the ammonia synthesis unit 2.

[0093] In the electrochemical nitrogen cycle system, except for the conversion and consumption within the unit, the transfer and change of components between each unit remain relatively balanced.

[0094] For example, for the ammonia synthesis unit, the gas processing unit processes the air, and the amount of N substance delivered to the ammonia synthesis unit is m1, and the amount of N substance provided by the electrolysis unit is m5, and the amount of N substance provided by the fuel cell to the ammonia synthesis unit is m6. The amount of N substance supplied by the ammonia synthesis unit to the electrolysis unit is m2, the amount of N substance supplied by the ammonia synthesis unit to the fuel cell is m3, and the amount of N substance supplied by the ammonia synthesis unit to the ecological unit is m4. For the simulated growth unit, the amount of N substance provided by the simulated growth unit to the fuel cell is m8, and the amount of N substance provided by the simulated growth unit to the electrolysis unit is m9. In addition, the amount of N substance supplied by the electrolysis unit to the fuel cell is m7.

[0095] From the growth dimension of plants and animals in the ecological unit, and combined with the component transfer between the ecological unit and the ammonia synthesis unit, the growth unit is simulated to store or consume ammonia provided by the ammonia synthesis unit through the second peristaltic pump, and to provide ammonia to the electrolysis unit and the fuel cell through the second peristaltic pump, which is specifically expressed as:

[0096]

[0097] Among them, ΔM is the amount of N substance that consumes nutrients in the simulated growth unit, M0 is the amount of N substance that is the benchmark for growth balance in the simulated growth unit, α1 is the conversion rate of the ammonia synthesis unit, α0 is the minimum conversion rate of N in the simulated growth unit, m1 is the amount of N substance provided by the gas processing unit to the ammonia synthesis unit, m5 is the amount of N substance provided by the electrolysis unit to the ammonia synthesis unit, m6 is the amount of N substance provided by the fuel cell to the ammonia synthesis unit, m8 is the amount of N substance provided by the simulated growth unit to the fuel cell, and m9 is the amount of N substance provided by the simulated growth unit to the electrolysis unit.

[0098] The values ​​of ΔM, M0, α0 and α1 are related to the specific application scenario and the type of the selection unit device, and are not specifically limited here.

[0099] like Figure 4 As shown, in order to ensure the balance of heat transfer in the electrochemical nitrogen cycle system, the electrochemical nitrogen cycle simulation system also includes a heat exchange unit, which is connected to the electrolysis unit, the ammonia synthesis unit and the fuel cell to balance the heat of the electrolysis unit, the ammonia synthesis unit and the fuel cell, and is specifically expressed as:

[0100] Q1≥(Q2+(Q 31 -Q 32 ))

[0101] Among them, Q1 is the heat dissipated by the fuel cell, Q2 is the heat required by the electrolysis unit, and Q 31 is the reaction heat required for the ammonia synthesis unit, Q 32 It is the energy released by ammonia synthesis in the ammonia synthesis unit.

[0102] For the electrolysis unit, ammonia is electrolyzed under the drive of electric energy to generate synthetic ammonia raw materials containing N and H2. The synthetic ammonia raw materials containing N are generated by the anode reaction and the cathode reaction.

[0103] There are several electrochemical pathways for ammonia electrolysis:

[0104] The first path is the electrolysis of ammonia to generate N2 and H2, which is specifically expressed as:

[0105] Anode: NH3+3OH - →1 / 2N2+3H2O+3e- ;

[0106] Cathode: 3H2O+3e - →3 / 2H2+3OH - .

[0107] The second path is the electrolysis of ammonia to generate NO and H2, which is specifically expressed as:

[0108] Anode: NH3+5OH - →NO+4H2O+5e - ;

[0109] Cathode: 4H2O+4e - →2H2+4OH - .

[0110] The third path is the electrolysis of ammonia to produce NO2 - And H2, specifically expressed as:

[0111] Anode: NH3+7OH - →NO2 - +5H2O+6e - ;

[0112] Cathode: 5H2O+5e - →5 / 2H2+5OH - .

[0113] The fourth path is the electrolysis of ammonia to produce NO3 - And H2, specifically expressed as:

[0114] Anode: NH3+9OH - →NO3 - +6H2O+8e - ;

[0115] Cathode: 6H2O+6e - →3H2+6OH - .

[0116] The heat exchange unit is used to balance the heat of the electrolysis unit, ammonia synthesis unit and fuel cell, and specifically includes:

[0117] Obtain the reaction heat, ammonia synthesis reaction amount and reaction enthalpy change required by the ammonia synthesis unit, and give the heat required by the ammonia synthesis unit;

[0118] Based on the analysis of the ammonia electrolysis path in the electrolysis unit, combined with multiple electrolysis parameter combinations and the historical probability data distribution of the ammonia electrolysis path under each electrolysis parameter combination, the proportion weight of each ammonia electrolysis path is given, which is specifically expressed as:

[0119]

[0120] Wherein, x is the proportional weight of the first ammonia electrolysis path, y is the proportional weight of the second ammonia electrolysis path, z is the proportional weight of the third ammonia electrolysis path, w is the proportional weight of the fourth ammonia electrolysis path, i is the number of the electrolysis parameter combination, n is the total number of electrolysis parameter combinations, β i is the occurrence probability of the i electrolysis parameter combination, j,x is the number of the probability of the first path of ammonia electrolysis, m x is the total number of probability cases of the first path of ammonia electrolysis, γ j,x is the probability value of the first path of ammonia electrolysis under j, x, P j,x For the corresponding γ j,x The ratio value of j,x is the number of the probability of occurrence of the first path of ammonia electrolysis, m y is the total number of probability cases of the second path of ammonia electrolysis, γ j,y is the probability value of the occurrence probability of the second path of ammonia electrolysis under j, y, P j,y For the corresponding γ j,y The ratio of j, y is the number of the probability of the second path of ammonia electrolysis, m z is the total number of probability cases of the third path of ammonia electrolysis, γ j,z is the probability value of the occurrence probability of the third path of ammonia electrolysis under j, z, P j,z For the corresponding γ j,z The ratio of j, z is the number of the probability of occurrence of the third path of ammonia electrolysis, m w is the total number of probability cases of the fourth path of ammonia electrolysis, γ j,w is the probability value of the fourth path of ammonia electrolysis under j, w, P j,w For the corresponding γ j,w The ratio value of

[0121] Based on the proportional weights of each ammonia electrolysis path, the heat required by the electrolysis unit is determined, which is specifically expressed as:

[0122]

[0123] Among them, m x is the amount of ammonia in the first path of ammonia electrolysis, m y is the amount of ammonia in the second path of ammonia electrolysis, m z is the amount of ammonia in the third path of ammonia electrolysis, m w is the amount of ammonia substance in the fourth ammonia electrolysis path, ΔH1 is the enthalpy variable of the first ammonia electrolysis path, ΔH2 is the enthalpy variable of the second ammonia electrolysis path, ΔH3 is the enthalpy variable of the third ammonia electrolysis path, and ΔH4 is the enthalpy variable of the fourth ammonia electrolysis path;

[0124] The heat supply of the fuel cell is determined based on the heat required by the ammonia synthesis unit and the heat required by the electrolysis unit, combined with the conversion efficiency of the heat exchange unit.

[0125] For the proportional weights of each ammonia electrolysis path, it is necessary to consider the values ​​of multiple electrolysis parameter combinations (including reaction parameters, reaction conditions, etc., for example, electrolyte type, electrolyte pH and ratio, electrolysis voltage, catalyst, electrolysis temperature and pressure, etc.).

[0126] For example, under the first electrolysis parameter combination, for the first path, the proportional weight may be P1, and the probability of occurrence of P1 is r1, the proportional weight may also be P2, and the probability of occurrence of P2 is r2, and the probability of occurrence when the proportional weight is P3 is r3, etc. Then, under the first electrolysis parameter combination, the proportional coefficient P should be: P1*r1+P2*r2+P3*r3.

[0127] Similarly, under the second electrolysis parameter combination, the ammonia electrolysis of each path, the proportional weight and the probability of occurrence are other corresponding values. Combined with the probability of occurrence of various electrolysis parameter combinations, a matrix of proportional weights under the four paths of ammonia electrolysis can be given. In this way, the heat required by the electrolysis unit can be determined more accurately, and then the power of the fuel cell that provides heat can be determined, achieving the energy balance of the entire nitrogen cycle system.

[0128] like Figure 5 As shown, the present invention also provides an electrochemical nitrogen cycle simulation method, which uses the electrochemical nitrogen cycle simulation system as described above and specifically includes the following steps:

[0129] Electrolyzing ammonia provided by the ecological unit and the ammonia synthesis unit through the electrolysis unit to generate synthetic ammonia raw materials, and providing the synthetic ammonia raw materials to the ammonia synthesis unit and the fuel cell respectively;

[0130] Based on the ecological unit, the ammonia provided by the ammonia synthesis unit is stored or consumed, and part of the ammonia is provided to the electrolysis unit and the fuel cell, and the other part of the ammonia is decomposed to generate a synthetic ammonia raw material, and the synthetic ammonia raw material is provided to the ammonia synthesis unit;

[0131] In the ammonia synthesis unit, ammonia is synthesized electrochemically from the synthetic ammonia raw materials provided by the electrolysis unit, the ecological unit and the fuel cell, and the synthesized ammonia is provided to the ecological unit, the fuel cell and the electrolysis unit;

[0132] In the fuel cell, chemical energy of ammonia or synthetic ammonia raw materials provided by the electrolysis unit, the ecological unit and the ammonia synthesis unit is converted into electrical energy, and power is supplied to the electrolysis unit and the ammonia synthesis unit, and synthetic ammonia raw materials are provided to the ammonia synthesis unit.

[0133] The present invention provides an electrochemical nitrogen cycle simulation system and a nitrogen cycle method, which have at least the following beneficial effects:

[0134] (1) The present invention takes the ecological unit as the basis of the nitrogen cycle system, provides an electrochemical nitrogen cycle simulation system, realizes a comprehensive energy cycle solution with ammonia as the nitrogen cycle carrier and accommodates renewable energy, and can effectively promote the development of nitrogen cycle scenario applications.

[0135] (2) The present invention uses the dynamic changes of nutrient storage and consumption in ecological units as the connection point and the balance and stability of the entire electrochemical nitrogen cycle system as the goal, thereby realizing the determination of the interactive relationship between components and energy between various units.

[0136] (3) The present invention takes into account the complexity of the ammonia electrolysis process, and through the sorting of historical test data under various combinations of parameters and conditions, combined with probability statistical analysis, an accurate prediction simulation of the heat required in the ammonia electrolysis process is achieved.

[0137] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An electrochemical nitrogen cycle simulation system, characterized in that: Specifically include: Electrolysis units, ammonia synthesis units, fuel cells and ecological units interconnected in pairs; An electrolysis unit, used for electrolyzing ammonia provided by the ecological unit and the ammonia synthesis unit to generate synthetic ammonia raw materials, and providing the synthetic ammonia raw materials to the ammonia synthesis unit and the fuel cell respectively; The ecological unit is used to store or consume ammonia provided by the ammonia synthesis unit, and provide part of the ammonia to the electrolysis unit and the fuel cell, decompose the other part of the ammonia to generate a synthetic ammonia raw material, and provide the synthetic ammonia raw material to the ammonia synthesis unit; the ecological unit includes a simulated growth device and a metabolite collection device connected to the outlet end of the simulated growth device; The simulated growth device is connected to the second peristaltic pump, stores or consumes ammonia provided by the ammonia synthesis unit via the second peristaltic pump, and provides ammonia to the electrolysis unit and the fuel cell via the second peristaltic pump; The outlet end of the metabolite collection device is connected to the ammonia synthesis unit to provide the synthetic ammonia raw material to the ammonia synthesis unit; The simulated growth device stores or consumes ammonia provided by the ammonia synthesis unit via the second peristaltic pump, and provides ammonia to the electrolysis unit and the fuel cell via the second peristaltic pump, which is specifically expressed as follows: Wherein, ΔM is the amount of nitrogen substance consumed by nutrients in the simulated growth device, M0 is the amount of nitrogen substance of the reference growth balance in the simulated growth device, α1 is the conversion rate of the ammonia synthesis unit, α0 is the minimum conversion rate of nitrogen in the simulated growth device, m1 is the amount of nitrogen substance provided by the gas processing unit to the ammonia synthesis unit, m5 is the amount of nitrogen substance provided by the electrolysis unit to the ammonia synthesis unit, m6 is the amount of nitrogen substance provided by the fuel cell to the ammonia synthesis unit, m8 is the amount of nitrogen substance provided by the simulated growth device to the fuel cell, and m9 is the amount of nitrogen substance provided by the simulated growth device to the electrolysis unit; An ammonia synthesis unit is used to electrochemically synthesize ammonia from the synthetic ammonia raw materials provided by the electrolysis unit, the ecological unit and the fuel cell, and provide the synthesized ammonia to the ecological unit, the fuel cell and the electrolysis unit; The fuel cell is used to convert chemical energy of ammonia or synthetic ammonia raw materials provided by the electrolysis unit, the ecological unit and the ammonia synthesis unit into electrical energy, supply power to the electrolysis unit and the ammonia synthesis unit, and provide synthetic ammonia raw materials to the ammonia synthesis unit.

2. The electrochemical nitrogen cycle simulation system according to claim 1, characterized in that: The cathode reaction chamber outlet and the anode reaction chamber outlet of the electrolysis unit are connected to the cathode gas collection tank inlet and the anode gas-liquid separator inlet respectively; The outlet end of the cathode gas collection tank is connected to the first humidification tank, and the first humidification tank is connected to the inlet end of the fuel cell to provide hydrogen and water to the fuel cell; The outlet end of the anode gas-liquid separator is respectively connected to the liquid collecting tank and the first anode gas collecting tank. The liquid collecting tank is connected to the ammonia synthesis unit via the first peristaltic pump to supply the nitrate-containing raw material to the ammonia synthesis unit. The first anode gas collecting tank is connected to the ammonia synthesis unit via the first pneumatic valve to supply the nitrogen-containing gas to the ammonia synthesis unit.

3. The electrochemical nitrogen cycle simulation system according to claim 1, characterized in that: The outlet end of the ammonia synthesis unit is connected to an ammonia collection tank, and the ammonia collection tank is connected to the ecological unit, the fuel cell and the electrolysis unit respectively through a second peristaltic pump, and provides ammonia to the ecological unit, the fuel cell and the electrolysis unit.

4. The electrochemical nitrogen cycle simulation system according to claim 1, characterized in that: The outlet end of the fuel cell is connected to the second anode gas collecting tank, and the second anode gas collecting tank is connected to the ammonia synthesis unit through the second pneumatic valve to supply the nitrogen-containing gas to the ammonia synthesis unit.

5. The electrochemical nitrogen cycle simulation system according to claim 1, characterized in that: It also includes a power supply unit and a gas processing unit; The power supply unit is used to supply power to the ammonia synthesis unit and the electrolysis unit; The gas processing unit is connected to the fuel cell and the ammonia synthesis unit respectively, and is used to obtain synthetic ammonia raw materials and provide them to the fuel cell and the ammonia synthesis unit.

6. The electrochemical nitrogen cycle simulation system according to claim 5, characterized in that: The gas processing unit includes an air separation device and a second humidification tank; The outlet end of the air separation device is respectively connected to the ammonia synthesis unit and the second humidification tank to provide nitrogen-containing gas to the ammonia synthesis unit, and to provide oxygen and water to the fuel cell through the second humidification tank.

7. The electrochemical nitrogen cycle simulation system according to claim 1, characterized in that: The electrochemical nitrogen cycle simulation system also includes a heat exchange unit, which is connected to the electrolysis unit, the ammonia synthesis unit and the fuel cell, and is used to balance the heat of the electrolysis unit, the ammonia synthesis unit and the fuel cell, which is specifically expressed as: Q1≥(Q2+(Q 31 -Q 32 )) Among them, Q1 is the heat dissipated by the fuel cell, Q2 is the heat required by the electrolysis unit, and Q 31 is the reaction heat required for the ammonia synthesis unit, Q 32 It is the energy released by ammonia synthesis in the ammonia synthesis unit.

8. An electrochemical nitrogen cycle simulation method, characterized in that: The electrochemical nitrogen cycle simulation system according to any one of claims 1 to 7 is used, and specifically comprises the following steps: Electrolyzing ammonia provided by the ecological unit and the ammonia synthesis unit through the electrolysis unit to generate synthetic ammonia raw materials, and providing the synthetic ammonia raw materials to the ammonia synthesis unit and the fuel cell respectively; Based on the ecological unit, the ammonia provided by the ammonia synthesis unit is stored or consumed, and part of the ammonia is provided to the electrolysis unit and the fuel cell, and the other part of the ammonia is decomposed to generate a synthetic ammonia raw material, and the synthetic ammonia raw material is provided to the ammonia synthesis unit; In the ammonia synthesis unit, ammonia is synthesized electrochemically from the synthetic ammonia raw materials provided by the electrolysis unit, the ecological unit and the fuel cell, and the synthesized ammonia is provided to the ecological unit, the fuel cell and the electrolysis unit; In the fuel cell, chemical energy of ammonia or synthetic ammonia raw materials provided by the electrolysis unit, the ecological unit and the ammonia synthesis unit is converted into electrical energy, and power is supplied to the electrolysis unit and the ammonia synthesis unit, and synthetic ammonia raw materials are provided to the ammonia synthesis unit.

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