Electro-hydrogen ammonia integrated system scheduling method and system considering thermal inertia of synthetic ammonia reactor
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-15
- Publication Date
- 2026-03-27
Smart Images
Figure CN121744645A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of renewable energy hydrogen production and ammonia synthesis technology, and in particular to a scheduling method and system for an integrated electro-hydrogen-ammonia system that takes into account the thermal inertia of the ammonia synthesis reactor. Background Technology
[0002] With the deepening of the global energy transition, building efficient, clean, and low-carbon integrated energy systems has become a key development direction. Among them, the integrated electricity-hydrogen-ammonia system, which couples renewable energy power generation with hydrogen and ammonia, has received widespread attention in recent years due to its enormous potential in achieving large-scale renewable energy consumption and long-term energy storage.
[0003] However, renewable energy power generation, represented by wind and solar power, is highly volatile, intermittent, and random. While these characteristics bring opportunities, they also pose significant challenges to the stable operation of integrated power-hydrogen-ammonia systems. Ammonia synthesis is a continuous chemical process conducted under high temperature and pressure, and its reactors (especially catalysts) have very strict requirements regarding the stability, temperature, and pressure of the feed gas. The volatility of wind and solar power generation is directly transmitted to the hydrogen production stage, causing fluctuations in the pressure and flow rate of hydrogen supplied for ammonia synthesis, thereby disrupting the thermal and chemical balance of the reactor. This not only affects ammonia synthesis efficiency but may also jeopardize the safety of the plant. Therefore, maintaining stable operation of the ammonia synthesis section is one of the core challenges in the coordinated control of the power-hydrogen-ammonia system.
[0004] However, current research on the optimal scheduling of "electricity-hydrogen-ammonia" systems largely focuses on the static energy balance and economic optimization of each unit within the system. Furthermore, existing scheduling strategies generally suffer from a key limitation: they mostly simplify the ammonia synthesis section into a "black box" model, considering only the relationship between total electrical input and ammonia production, while ignoring the significant thermal inertia within the reactor. Ammonia synthesis is a typical exothermic and reversible process, with its reaction rate and conversion rate strongly dependent on the temperature of the catalyst bed inside the reactor. Maintaining a suitable and stable reaction temperature is a prerequisite for ensuring ammonia synthesis efficiency, catalyst lifespan, and plant safety. Temperature control in ammonia synthesis reactors exhibits significant dynamic characteristics, with large response inertia and strong hysteresis. Frequent or drastic power adjustments can disrupt the reactor's thermal equilibrium. If the thermal inertia of the ammonia synthesis unit is ignored in the scheduling model, power commands exceeding the reactor's safe and efficient operating thresholds may be issued, causing irreversible damage to the ammonia synthesis unit. Summary of the Invention
[0005] In view of this, and to address the above shortcomings, it is necessary to propose a scheduling method and system for an integrated electro-hydrogen-ammonia system that takes into account the thermal inertia of the ammonia synthesis reactor, so as to solve the problem of low system reliability and safety performance caused by neglecting thermal inertia in existing solutions.
[0006] In a first aspect, the present invention provides a method for scheduling an integrated electro-hydrogen-ammonia system that takes into account the thermal inertia of a synthetic ammonia reactor, comprising:
[0007] By modeling the heat balance relationship of the ammonia synthesis reactor, a dynamic thermal process model of the ammonia synthesis reactor is constructed; wherein, the dynamic thermal process model is used to characterize the dynamic relationship between temperature response and various factors such as feed gas flow and reaction exothermics.
[0008] The dynamic thermal process model is transformed into scheduling constraints and integrated into the scheduling framework of the integrated electro-hydrogen-ammonia system. At the same time, the scheduling model is constructed by taking the total operating cost of the system as the objective function and combining the operating constraints of each unit.
[0009] The new energy output data is used as input to the scheduling model for solution, and an optimized production scheduling scheme for the integrated power-hydrogen-ammonia system is output. The scheduling operation is then carried out based on the output optimized production scheduling scheme.
[0010] Preferably, the dynamic thermal process model of the ammonia synthesis reactor includes: a temperature model of the synthesis tower, a natural heat dissipation model of the synthesis tower, a reaction heat model, an inlet / outlet gas heat model, and a cooling capacity model.
[0011] Preferably, the temperature model of the synthesis tower is: ;
[0012] in, The temperature of the synthesis tower. The total heat capacity of the synthesis tower, The heat of reaction, and These represent the heat of the gas entering and exiting the tower, respectively. The cooling capacity obtained through quenching or heat exchange is an actively controlled variable. The heat lost to the environment;
[0013] The natural heat dissipation model of the synthesis tower is as follows: ;
[0014] in, Ambient temperature; Equivalent thermal resistance for heat dissipation;
[0015] The reaction heat model is as follows: ;
[0016] in, This describes the status of the ammonia synthesis section; 1 indicates operation, and 0 indicates non-operation. Load factor;
[0017] The heat model for the inlet / outlet gas is as follows: ;
[0018] in, Indicates the gas flow rate at the inlet / outlet of the tower. The specific heat capacity of the gas entering / exiting the tower. This refers to the temperature of the gas entering / exiting the tower.
[0019] Preferably, the construction process of the scheduling model specifically includes:
[0020] Determine the constraints on the refrigeration capacity of the ammonia synthesis tower, the gas flow rate into the synthesis tower, and the heat of reaction, and establish the state switching logic of the synthesis section and the operation constraint model of the ammonia synthesis section.
[0021] Establish an operational constraint model for the boiler under construction, relevant variable constraints for the renewable energy hydrogen production station, and overall system power balance constraints;
[0022] Based on the dynamic thermal process models and the constraint models described, an objective function is determined to minimize the total operating cost of the system.
[0023] Preferably, the refrigeration capacity constraint of the ammonia synthesis tower includes: ;
[0024] in, This is the upper limit of the refrigeration capacity of the synthesis tower;
[0025] The flow rate constraint of the synthesis tower inlet gas includes: ; ;
[0026] in, The boiler heating flow rate at startup;
[0027] The reaction heat constraint includes: ;
[0028] in, Heat generated per unit load rate;
[0029] The state switching logic constraints of the synthesis section include: ; ;
[0030] in, These represent the production, shutdown, and start-up statuses of the ammonia synthesis section at time t, respectively. ; ; ;
[0031] use , Actions that indicate transitioning from a shutdown state to a production state, or from a production state to a shutdown state, include: ; ; ; ;
[0032] in, This is the lower limit of the operating temperature of the synthesis tower;
[0033] Introducing the Big M method, the transformation is as follows: ;
[0034] Where M is a sufficiently large positive number; ; ; ;
[0035] in, and These are the lower and upper limits of the synthetic loading rate; and These represent the lower and upper limits of climbing ability;
[0036] The operational constraints of the ammonia synthesis section include: ; ; ;
[0037] in, , This represents the hydrogen consumption and ammonia yield under rated load. For the power load of the ammonia production process, Power consumption of basic auxiliary equipment; This is the power consumption coefficient per unit load.
[0038] Preferably, the operating constraints of the boiler in operation include: ;
[0039] in, For the heating power of the electric boiler, This refers to the upper limit of the heating power of an electric boiler.
[0040] The relevant variable constraints for the renewable energy hydrogen production station include: ; ; ;
[0041] in, Hydrogen production consumes electricity. For hydrogen production flow rate, The power consumption per unit of hydrogen production. This represents the upper limit of hydrogen production rate at hydrogen production stations;
[0042] The overall system power balance constraints include: ; ;
[0043] in, Contribute to wind and solar power generation Power supplied to the grid This represents the upper limit of the power output of the power grid.
[0044] Preferably, the objective function is: ;
[0045] Where T is the scheduling duration, The price of ammonia. The purchase price of electricity from the grid. The start-up and shutdown costs for the ammonia synthesis section.
[0046] Secondly, the present invention provides an integrated electro-hydrogen-ammonia system scheduling system that takes into account the thermal inertia of a synthetic ammonia reactor. The system includes: a dynamic thermal process model construction module, a scheduling model construction module, and a solution output module.
[0047] The dynamic thermal process model construction module is configured to construct a dynamic thermal process model of the ammonia synthesis reactor by modeling the heat balance relationship of the ammonia synthesis reactor; wherein, the dynamic thermal process model is used to characterize the dynamic correlation between temperature response and various factors such as feed gas flow and reaction exothermic reaction.
[0048] The scheduling model construction module is configured to transform the dynamic thermal process model into scheduling-level constraints and integrate them into the scheduling framework of the integrated electro-hydrogen-ammonia system. At the same time, it constructs a completed scheduling model with the total system operating cost as the objective function and the operating constraints of each unit.
[0049] The solution output module is configured to take the new energy output data as input to the scheduling model for solution, output an optimized production scheduling scheme for the integrated power-hydrogen-ammonia system, and perform scheduling operations based on the output optimized production scheduling scheme.
[0050] Thirdly, the present invention provides a computing device including a memory and a processor, wherein the memory stores executable code, and when the processor executes the executable code, it performs any of the methods described in the first aspect above.
[0051] Fourthly, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to perform any of the methods described in the first aspect above.
[0052] As can be seen from the above technical solution, the integrated electro-hydrogen-ammonia system scheduling method and system considering the thermal inertia of the ammonia synthesis reactor provided by this invention first models the thermal balance relationship of the ammonia synthesis reactor to construct a dynamic thermal process model of the reactor. This model characterizes the dynamic correlation between its temperature response and factors such as feed gas flow and reaction exothermics, reflecting its thermal inertia and providing a physical basis for quantifying the impact of thermal inertia at the scheduling level. Furthermore, the dynamic thermal process model is transformed into constraints at the scheduling level and integrated into the scheduling framework of the integrated electro-hydrogen-ammonia system. Simultaneously, a complete scheduling model is constructed using the total system operating cost as the objective function, combined with the operating constraints of each unit. Finally, the new energy output data is used as input for solution, outputting an optimized production scheduling scheme for the integrated electro-hydrogen-ammonia system. Thus, this scheme fully considers the significant thermal inertia problem existing inside the reactor, enabling the smoothing of new energy fluctuations while ensuring that the ammonia synthesis reactor always operates within a safe, reliable, and efficient range. Attached Figure Description
[0053] Figure 1 A flowchart of an integrated electro-hydrogen-ammonia system scheduling method considering the thermal inertia of a synthetic ammonia reactor, provided as an embodiment of the present invention.
[0054] Figure 2 This is an overall structural diagram of a renewable energy power generation system for hydrogen production and ammonia synthesis.
[0055] Figure 3 This is a schematic diagram of an integrated electro-hydrogen-ammonia system scheduling system that takes into account the thermal inertia of a synthetic ammonia reactor, provided as an embodiment of the present invention.
[0056] Figure 4 This is a schematic diagram of the power output curve for new energy generation.
[0057] Figure 5 This is a schematic diagram showing the changes in the operating status of the ammonia synthesis section.
[0058] Figure 6 This is a schematic diagram showing the load rate changes in the ammonia synthesis section.
[0059] Figure 7 This is a schematic diagram of the temperature change curve of the synthesis tower. Detailed Implementation
[0060] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0061] like Figure 1 As shown, the present invention provides a method for scheduling an integrated electro-hydrogen-ammonia system that takes into account the thermal inertia of a synthetic ammonia reactor. This method may include the following steps:
[0062] Step 101: By modeling the heat balance relationship of the ammonia synthesis reactor, a dynamic thermal process model of the ammonia synthesis reactor is constructed; wherein, the dynamic thermal process model is used to characterize the dynamic correlation between temperature response and various factors such as feed gas flow and reaction exothermics.
[0063] Step 102: Transform the dynamic thermal process model into scheduling constraints and integrate it into the scheduling framework of the integrated electro-hydrogen-ammonia system. At the same time, construct the completed scheduling model with the total system operating cost as the objective function and the operating constraints of each unit.
[0064] Step 103: Use the new energy output data as input to solve the scheduling model, output an optimized production scheduling scheme for the integrated power-hydrogen-ammonia system, and perform scheduling operations based on the output optimized production scheduling scheme.
[0065] In this embodiment, a dynamic thermal process model of the ammonia synthesis reactor is first constructed by modeling the thermal balance relationship of the reactor. This model characterizes the dynamic correlation between the reactor's temperature response and factors such as feed gas flow and reaction exothermics, reflecting its thermal inertia and providing a physical basis for quantifying the impact of thermal inertia at the scheduling level. Furthermore, the dynamic thermal process model is transformed into scheduling constraints and integrated into the scheduling framework of the integrated electro-hydrogen-ammonia system. Simultaneously, a complete scheduling model is constructed using the total system operating cost as the objective function, combined with the operating constraints of each unit. Finally, the renewable energy output data is used as input for solution, outputting an optimized production scheduling scheme for the integrated electro-hydrogen-ammonia system. Thus, this scheme fully considers the significant thermal inertia problem within the reactor, mitigating the volatility of renewable energy while ensuring that the ammonia synthesis reactor always operates within a safe, reliable, and efficient range.
[0066] The following is a detailed explanation of each step.
[0067] For step 101, a dynamic thermal process model of the ammonia synthesis reactor is constructed by modeling the heat balance relationship of the ammonia synthesis reactor; wherein, the dynamic thermal process model is used to characterize the dynamic relationship between temperature response and various factors such as feed gas flow and reaction exothermics.
[0068] This invention focuses on a wind-solar hydrogen production to ammonia synthesis system via an indirect synthesis route, the overall structure of which is shown in the diagram below. Figure 2 As shown. The industrial-grade renewable energy-based hydrogen production and ammonia synthesis system includes a water electrolysis hydrogen production section, a compression buffer section, and an ammonia synthesis section. A model is constructed for the dynamic thermal process of the ammonia synthesis reactor, including a temperature model of the synthesis tower, a natural heat dissipation model of the synthesis tower, a reaction heat model, an inlet / outlet gas heat model, and a cooling capacity model. Specifically, the model is represented as follows:
[0069] (1) Temperature model of the synthesis tower
[0070] In one embodiment, the overall operation and thermal management of the ammonia synthesis section are handled by the tower as a whole, rather than by internal temperature control or structural optimization. Therefore, when modeling the thermal dynamics of the synthesis tower, the tower is treated as a lumped-parameter mass body. Consequently, the thermal balance equation for the synthesis tower, i.e., the temperature model, is as follows: ;
[0071] in, The temperature of the synthesis tower. The total heat capacity of the synthesis tower, including the tower structure, catalyst packing, and the material flow therein; The heat of reaction, and These represent the heat of the gas entering and exiting the tower, respectively. The cooling capacity obtained through quenching or heat exchange is an actively controlled variable. The heat lost to the environment is the main reason for the cooling of the synthesis tower after shutdown.
[0072] (2) The natural heat dissipation model of the synthesis tower is as follows:
[0073] This scheme primarily considers heat transfer, therefore the natural heat dissipation model for the synthesis tower is as follows: ;
[0074] in, Ambient temperature; Equivalent thermal resistance for heat dissipation
[0075] (3) The reaction heat model is
[0076] The heat of reaction is determined by the operating conditions and can be approximated by the load factor. A linear function. Only when the ammonia synthesis section is in operation ( For the reaction to proceed, heat of reaction must be generated. ;
[0077] in, This describes the status of the ammonia synthesis section; 1 indicates operation, and 0 indicates non-operation. Load factor;
[0078] (4) The heat model for the gas entering / exiting the tower is as follows:
[0079] Running status ( When the gas entering and exiting the tower carries heat, the heat is determined by its flow rate, temperature, and specific heat capacity (which depends on the gas composition), then: ;
[0080] in, Indicates the gas flow rate at the inlet / outlet of the tower. The specific heat capacity of the gas entering / exiting the tower. Let represent the inlet / outlet gas temperature. The inlet / outlet gas temperature and specific heat capacity can be approximated as constants, while the inlet / outlet gas flow rate can be approximated as a linear function of the load rate.
[0081] (5) Cooling capacity model
[0082] The tower temperature is maintained constant by controlling the quench gas flow rate (in a quench-type synthesis tower) or the heat exchange flow rate (in a heat exchange-type synthesis tower). Therefore, its cooling heat... For actively controlled variables.
[0083] For step 102: The dynamic thermal process model is transformed into scheduling constraints and integrated into the scheduling framework of the integrated electro-hydrogen-ammonia system. At the same time, the total operating cost of the system is used as the objective function, and the operating constraints of each unit are combined to construct the completed scheduling model.
[0084] This step can be implemented in the following way:
[0085] S21: Determine the constraints on the cooling capacity of the ammonia synthesis tower, the gas flow rate at the inlet of the synthesis tower, and the heat of reaction, and establish the state switching logic of the synthesis section and the operation constraint model of the ammonia synthesis section.
[0086] In this step, each constraint model can be represented as follows:
[0087] (1) Cooling capacity constraint of ammonia synthesis tower
[0088] When the synthesis tower is in operation, the reaction is exothermic. Excess heat is removed through quenching or a cooling heat exchanger to prevent overheating and potential safety issues such as catalyst sintering. The refrigeration capacity is constrained as follows: ;
[0089] in, This is the upper limit of the refrigeration capacity of the synthesis tower; here It can be equal to 0 or 1, and its value is determined by the operating conditions. This constraint means that if the ammonia synthesis is operating under production conditions... =1, therefore If ammonia synthesis is not operating under production conditions =0, then .
[0090] (2) Constraints on the gas flow rate at the synthesis tower
[0091] Regarding flow rate, the total inlet gas flow rate equals the direct inlet gas flow rate plus the boiler heating flow rate at startup. Therefore, the following inequality constraint must be satisfied. ;
[0092] According to the law of conservation of mass, the inlet gas flow rate is equal to the outlet gas flow rate, that is: ;
[0093] in, The boiler heating flow rate at startup.
[0094] (3) Reaction heat confinement
[0095] The reaction within the synthesis tower generates heat. The synthesis reaction within the tower occurs at 400°C and 150 bar. .;
[0096] The heat of reaction per ton of ammonia is -3.07 MJ / kg. Ignoring other side reactions, the heat of reaction can be modeled as the loading rate. Linear functions: ;
[0097] in, Heat generated per unit load rate;
[0098] (4) Logic constraints for state switching of the composite section
[0099] The ammonia synthesis (AS) section can switch between start-up, production, and shutdown states, satisfying the following logical constraints: ; ;
[0100] in, These represent the production, shutdown, and start-up status of the ammonia synthesis section at time t, respectively.
[0101] The transitions between system states follow a path that forms a unidirectional loop: shutdown state Can only be transferred to driving mode Driving status Only transferable to production status production status It can only be transferred back to the shutdown state. The following constraints must be met: ; ; ;
[0102] use , This represents the action of transitioning from a shutdown state to a production state, or from a production state to a production state; it is a 0-1 variable. This signifies that the ammonia synthesis section has entered production. This indicates that the ammonia synthesis section has ceased production. This is defined by the following constraints: ; ; ;
[0103] Whether it can be switched to production mode depends on whether the temperature of the synthesis tower meets the catalyst activity requirements, i.e., it requires... Only when the time is right can the system switch to production mode, that is: ;
[0104] in, This is the lower limit of the operating temperature of the synthesis tower;
[0105] To embed it into mixed integer programming, we introduce the Big M method, transforming it into: ;
[0106] Where M is a sufficiently large positive number;
[0107] In addition, the load level of the ammonia synthesis section has an upper limit and ramp-up restrictions, and the load rate cannot change abruptly during non-start-up and shutdown. The load rate must be at or below the lower limit of the load at the moment of start-up and the moment before shutdown. Therefore, the following constraints must be met: ; ; ;
[0108] in, and These are the lower and upper limits of the synthetic loading rate; and These represent the lower and upper limits of climbing ability;
[0109] (5) Operational constraints of the ammonia synthesis section
[0110] Hydrogen is consumed in the production of synthetic ammonia. Ammonia production With load rate A linear relationship exists: ; ;
[0111] The power load of the ammonia production process includes the power consumption of compressors, pumps, etc., denoted as . It can generally be considered to have a linear relationship with the ammonia synthesis load level, satisfying the following relationship: ;
[0112] in, , This represents the hydrogen consumption and ammonia yield under rated load. For the power load of the ammonia production process, Power consumption of basic auxiliary equipment; This is the power consumption coefficient per unit load.
[0113] S22: Establish an operational constraint model for the boiler under construction, relevant variable constraints for the renewable energy hydrogen production station, and overall system power balance constraints;
[0114] This step involves first establishing an operational constraint model for the boiler in operation, including upper and lower limits for its heating power and necessary equipment start-up and shutdown logic constraints. Second, the relevant variables and constraints of the renewable energy hydrogen production station are identified. Finally, a system-wide power balance constraint is constructed to ensure real-time power supply and demand balance within the system. Specifically, each constraint can be represented as follows:
[0115] (1) Operational constraints of boilers under construction
[0116] Boilers can only be started under low load or in start-up conditions, therefore their heating power must meet the following constraints: ;
[0117] in, For the heating power of the electric boiler, This refers to the upper limit of the heating power of an electric boiler.
[0118] (2) Relevant variable constraints of renewable energy hydrogen production stations
[0119] Hydrogen production stations that are integrated with ammonia synthesis typically have a large capacity. Considering the start-up and shutdown combinations of hydrogen generators and load distribution, the load of the hydrogen production station can be considered to be continuously adjusted between 0 and rated load; therefore, its operating constraints are as follows: ; ;
[0120] The hydrogen production rate equals the hydrogen consumption in ammonia synthesis, thus satisfying the constraint: ;
[0121] in, Hydrogen production consumes electricity. For hydrogen production flow rate, The power consumption per unit of hydrogen production. This is the upper limit of the hydrogen production rate of the hydrogen production station.
[0122] (3) Power balance constraints of the whole system
[0123] All electricity used by the entire system should come from renewable energy generation, but the grid can provide a small amount of backup power to ensure the safety of hydrogen production and ammonia synthesis auxiliary equipment during periods of low wind and solar power output or power outages. However, due to policy restrictions, power cannot be supplied to the grid. The power supply for the entire system must meet the following constraints: ; ;
[0124] in, Contribute to wind and solar power generation Power supplied to the grid This represents the upper limit of the power output of the power grid.
[0125] S23: Based on the dynamic thermal process models and the constraint models described, determine the objective function that minimizes the total operating cost of the system.
[0126] In this step, we consider determining the objective function for system operation. The objective function is to minimize the total system operating cost, taking into account ammonia sales revenue, electricity purchase cost, and start-up and shutdown costs. Specifically, the objective function can be expressed as: ;
[0127] Where T is the scheduling duration, The price of ammonia. The purchase price of electricity from the grid. The start-up and shutdown costs of the ammonia synthesis section mainly consider the wear and tear costs of catalysts and equipment.
[0128] Step 103: Use the new energy output data as input to solve the scheduling model, output an optimized production scheduling scheme for the integrated power-hydrogen-ammonia system, and perform scheduling operations based on the output optimized production scheduling scheme.
[0129] In this step, the example constructed by the patent adopts a mixed integer linear programming (MILP) model. The gurobi solver is called in Mathematica to solve the model and obtain the system production scheduling optimization scheme.
[0130] In addition, such as Figure 3 As shown, the present invention also provides an integrated electro-hydrogen-ammonia system scheduling system that takes into account the thermal inertia of the ammonia synthesis reactor. The system includes: a dynamic thermal process model construction module 301, a scheduling model construction module 302, and a solution output module 303.
[0131] The dynamic thermal process model construction module 301 is configured to construct a dynamic thermal process model of the ammonia synthesis reactor by modeling the heat balance relationship of the ammonia synthesis reactor; wherein, the dynamic thermal process model is used to characterize the dynamic correlation between temperature response and various factors such as feed gas flow and reaction exothermic reaction.
[0132] The scheduling model construction module 302 is configured to transform the dynamic thermal process model into scheduling-level constraints and integrate them into the scheduling framework of the integrated electro-hydrogen-ammonia system. At the same time, it constructs a completed scheduling model with the total system operating cost as the objective function and the operating constraints of each unit.
[0133] The solution output module 303 is configured to take the new energy output data as input to the scheduling model for solution, output an optimized production scheduling scheme for the integrated power-hydrogen-ammonia system, and perform scheduling operations based on the output optimized production scheduling scheme.
[0134] The technical effects of this solution will be further illustrated below with specific application examples.
[0135] Based on the 7-day (168-hour) output data of a 400 MW wind power plant and a 200 MW photovoltaic power plant (e.g. Figure 4 Using the input shown (as illustrated), the scheduling model of the integrated electro-hydrogen-ammonia system is solved. This model is expressed as a mixed-integer linear programming problem, and its optimization results are as follows.
[0136] Figure 5 The timeline operation status of the ammonia synthesis section was displayed over a 168-hour period. Figure 6 This is to show the time-series changes in ammonia synthesis load under new energy power generation scenarios. Combined with... Figure 4 , Figure 5 and Figure 6It can be seen that during the period from 66 to 80 hours, due to insufficient renewable energy output, the ammonia synthesis section entered a shutdown state, and the ammonia synthesis load dropped to zero; after the wind and solar power output gradually recovered, the section restarted and returned to production.
[0137] Figure 7 The figure shows the temperature change of the synthesis tower over time, where the solid blue line represents the actual tower temperature and the dashed red line represents the upper and lower limits of the allowable temperature under production conditions. The results indicate that under this scheduling scheme, the synthesis tower temperature is consistently controlled within a highly efficient and safe range: during production, the temperature is maintained within the optimal activity range of the catalyst; during shutdown, the tower temperature gradually decreases due to environmental heat dissipation, meeting system safety requirements.
[0138] The present invention also provides a computing device, including a memory and a processor, wherein the memory stores executable code, and when the processor executes the executable code, it runs the method as described in the above embodiments.
[0139] The present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to perform the method as described in any of the above embodiments.
[0140] The system embodiments provided by this invention are based on the same inventive concept as the method embodiments in this specification. For details, please refer to the description in the method embodiments of this specification, which will not be repeated here.
[0141] The modules or units in the device of this invention can be merged, divided, and deleted according to actual needs. The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the invention. Those skilled in the art will understand that implementing all or part of the processes of the above embodiments and making equivalent changes according to the claims of this invention still fall within the scope of the invention.
Claims
1. A method for scheduling an integrated electro-hydrogen-ammonia system considering the thermal inertia of a synthetic ammonia reactor, characterized in that, include: By modeling the heat balance relationship of the ammonia synthesis reactor, a dynamic thermal process model of the ammonia synthesis reactor is constructed; wherein, the dynamic thermal process model is used to characterize the dynamic relationship between temperature response and various factors such as feed gas flow and reaction exothermics. The dynamic thermal process model is transformed into scheduling constraints and integrated into the scheduling framework of the integrated electro-hydrogen-ammonia system. At the same time, the scheduling model is constructed by taking the total operating cost of the system as the objective function and combining the operating constraints of each unit. The new energy output data is used as input to the scheduling model for solution, and an optimized production scheduling scheme for the integrated power-hydrogen-ammonia system is output. The scheduling operation is then carried out based on the output optimized production scheduling scheme.
2. The integrated electro-hydrogen-ammonia system scheduling method considering the thermal inertia of the ammonia synthesis reactor according to claim 1, characterized in that, The dynamic thermal process model of the ammonia synthesis reactor includes: a temperature model of the synthesis tower, a natural heat dissipation model of the synthesis tower, a reaction heat model, an inlet / outlet gas heat model, and a cooling capacity model.
3. The integrated electro-hydrogen-ammonia system scheduling method considering the thermal inertia of the ammonia synthesis reactor according to claim 2, characterized in that, The temperature model of the synthesis tower is: ； in, The temperature of the synthesis tower. The total heat capacity of the synthesis tower, The heat of reaction, and These represent the heat of the gas entering and exiting the tower, respectively. The cooling capacity obtained through quenching or heat exchange is an actively controlled variable. The heat lost to the environment; The natural heat dissipation model of the synthesis tower is as follows: ； in, Ambient temperature; Equivalent thermal resistance for heat dissipation; The reaction heat model is as follows: ； in, This describes the status of the ammonia synthesis section; 1 indicates operation, and 0 indicates non-operation. Load factor; The heat model for the inlet / outlet gas is as follows: ； in, Indicates the gas flow rate at the inlet / outlet of the tower. The specific heat capacity of the gas entering / exiting the tower. This refers to the temperature of the gas entering / exiting the tower.
4. The integrated electro-hydrogen-ammonia system scheduling method considering the thermal inertia of the ammonia synthesis reactor according to claim 3, characterized in that, The construction process of the scheduling model specifically includes: Determine the constraints on the refrigeration capacity of the ammonia synthesis tower, the gas flow rate into the synthesis tower, and the heat of reaction, and establish the state switching logic of the synthesis section and the operation constraint model of the ammonia synthesis section. Establish an operational constraint model for the boiler under construction, relevant variable constraints for the renewable energy hydrogen production station, and overall system power balance constraints; Based on the dynamic thermal process models and the constraint models described, an objective function is determined to minimize the total operating cost of the system.
5. The integrated electro-hydrogen-ammonia system scheduling method considering the thermal inertia of the ammonia synthesis reactor according to claim 4, characterized in that, The refrigeration capacity constraint of the ammonia synthesis tower includes: ； in, This is the upper limit of the refrigeration capacity of the synthesis tower; The flow rate constraint of the synthesis tower inlet gas includes: ； ； in, The boiler heating flow rate at startup; The reaction heat constraint includes: ； in, Heat generated per unit load rate; The state switching logic constraints of the synthesis section include: ； ； in, These represent the production, shutdown, and start-up statuses of the ammonia synthesis section at time t, respectively. ； ； ； use , Actions that indicate transitioning from a shutdown state to a production state, or from a production state to a shutdown state, include: ； ； ； ； in, This is the lower limit of the operating temperature of the synthesis tower; Introducing the Big M method, the transformation is as follows: ； Where M is a sufficiently large positive number; ； ； ； in, and These are the lower and upper limits of the synthetic loading rate; and These represent the lower and upper limits of climbing ability; The operational constraints of the ammonia synthesis section include: ； ； ； in, , This represents the hydrogen consumption and ammonia yield under rated load. For the power load of the ammonia production process, Power consumption of basic auxiliary equipment; This is the power consumption coefficient per unit load.
6. The integrated electro-hydrogen-ammonia system scheduling method considering the thermal inertia of the ammonia synthesis reactor according to claim 5, characterized in that, The operating constraints of the boiler in operation include: ； in, For the heating power of the electric boiler, This refers to the upper limit of the heating power of an electric boiler. The relevant variable constraints for the renewable energy hydrogen production station include: ； ； ； in, Hydrogen production consumes electricity. For hydrogen production flow rate, The power consumption per unit of hydrogen production. This represents the upper limit of hydrogen production rate at hydrogen production stations; The overall system power balance constraints include: ； ； in, Contribute to wind and solar power generation Power supplied to the grid This represents the upper limit of the power output of the power grid.
7. The integrated electro-hydrogen-ammonia system scheduling method considering the thermal inertia of the ammonia synthesis reactor according to claim 6, characterized in that, The objective function is: ； Where T is the scheduling duration, The price of ammonia. The purchase price of electricity from the grid. The start-up and shutdown costs for the ammonia synthesis section.
8. A scheduling system for an integrated electro-hydrogen-ammonia system that takes into account the thermal inertia of a synthetic ammonia reactor, characterized in that, The system includes: a dynamic thermal process model building module, a scheduling model building module, and a solution output module; The dynamic thermal process model construction module is configured to construct a dynamic thermal process model of the ammonia synthesis reactor by modeling the heat balance relationship of the ammonia synthesis reactor; wherein, the dynamic thermal process model is used to characterize the dynamic correlation between temperature response and various factors such as feed gas flow and reaction exothermic reaction. The scheduling model construction module is configured to transform the dynamic thermal process model into scheduling-level constraints and integrate them into the scheduling framework of the integrated electro-hydrogen-ammonia system. At the same time, it constructs a completed scheduling model with the total system operating cost as the objective function and the operating constraints of each unit. The solution output module is configured to take the new energy output data as input to the scheduling model for solution, output an optimized production scheduling scheme for the integrated power-hydrogen-ammonia system, and perform scheduling operations based on the output optimized production scheduling scheme.
9. A computing device, comprising a memory and a processor, wherein executable code is stored in the memory, and when the processor executes the executable code, it performs the method as described in any one of claims 1-7 above.
10. A computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to perform the method as described in any one of claims 1-7.