A process industry production control method and system based on waste heat recovery optimization

Abstract

The application discloses a kind of process industry production control method and system based on waste heat recovery optimization, it is related to industrial production control field, the method comprises: according to the thermodynamic measurement data of each process stream in production system, under the minimum heat transfer temperature difference constraint, constructs multiple temperature intervals;According to the thermodynamic measurement data of each process stream, cascade calculation is carried out to multiple temperature intervals, to determine the upper limit of available waste heat;With the upper limit of available waste heat as the energy constraint of production system, with the maximum output flow of primary steam, secondary steam and heat medium water of production system as target, successively constructs and solves the optimization model of the output flow of primary steam, secondary steam and heat medium water, obtains the optimized output flow of primary steam, secondary steam and heat medium water, to control production system, to realize waste heat recovery of production system.By implementing the present application, the calculation efficiency of solving waste heat recovery and reuse in the production system can be improved.

Description

Technical Field

[0001] This application relates to the field of industrial production control, and in particular to a process industrial production control method and system based on waste heat recovery optimization. Background Technology

[0002] In process industries such as petrochemicals, coal chemicals, and fine chemicals, a large amount of energy is transferred as heat between different temperature levels during production. Waste heat is typically recovered and reused through heat exchange networks to achieve efficient energy utilization. Low-temperature waste heat can be used to heat water and produce low-pressure steam, while high-temperature waste heat can be used to produce high-pressure steam, thus achieving cascaded utilization and conversion of energy. However, existing methods for calculating waste heat recovery and reuse often require step-by-step manual estimation or rely on complex nonlinear optimization models. These calculations are cumbersome, have poor convergence, and are difficult to quickly obtain feasible results, resulting in the efficiency of waste heat recovery for production control failing to meet actual production control needs. Therefore, it is necessary to optimize the calculation of waste heat recovery and reuse to improve computational efficiency and meet the requirements of actual production control.

[0003] Traditional integrated thermal analysis methods, such as pinch analysis or the problem table method, while capable of determining minimum utility requirements, struggle to simultaneously consider the coordinated heat extraction of multiple stages of steam and heat transfer fluid. This results in an inability to quickly provide a quantitative distribution of steam production at each stage, limiting the practical application of traditional analysis methods. Therefore, improving the computational efficiency of waste heat recovery and reuse to meet actual production control needs remains a pressing technical problem that needs to be solved. Summary of the Invention

[0004] This application provides a process industrial production control method and system based on waste heat recovery optimization, in order to solve the technical problem that the computational efficiency of solving waste heat recovery and reuse in existing production systems cannot meet the actual production needs.

[0005] According to a first aspect of the embodiments of this application, a process industrial production control method based on waste heat recovery optimization is provided, comprising: Acquire thermal measurement data of each process material in the production system, and construct multiple temperature ranges of the production system based on the thermal measurement data of each process material under the preset minimum heat transfer temperature difference constraint. Based on the thermal measurement data of each process material, cascade calculations are performed on the multiple temperature ranges to determine the upper limit of available waste heat of the production system. Using the available waste heat upper limit as the energy constraint of the production system, and aiming to maximize the output flow rates of primary steam, secondary steam, and heat transfer water in the production system, optimization models for the output flow rates of primary steam, secondary steam, and heat transfer water are constructed and solved sequentially. The output flow rates of primary steam, secondary steam, and heat transfer water are optimized to obtain the optimized output flow rates of primary steam, secondary steam, and heat transfer water; wherein, the pressure of primary steam is greater than the pressure of secondary steam. The production system is controlled based on the optimized output flow rates of primary steam, secondary steam, and heat transfer water to achieve waste heat recovery.

[0006] This application first acquires the thermal measurement data of each process material in the production system, and under the constraint of minimum heat transfer temperature difference, constructs multiple temperature ranges of the production system. Then, it performs cascade calculations on multiple temperature ranges to determine the upper limit of available waste heat in the production system. By constructing multiple temperature ranges and performing cascade calculations, it is possible to accurately calculate the data within each range while enabling interaction between ranges through cascading, thereby accelerating the efficiency of range cascade calculations and improving the computational efficiency of solving the waste heat recovery and reuse problem in the production system. Then, using the upper limit of available waste heat as an energy constraint, and aiming to maximize the output flow rates of primary steam, secondary steam, and heat transfer water in the production system, it sequentially constructs optimization models and solves them to obtain their respective optimized output flow rates. Then, it implements control over the production system. By sequentially decomposing the complex problem of waste heat recovery into sub-problems of sequentially optimizing the maximum output flow rates of primary steam, secondary steam, and heat transfer water under the upper limit of available waste heat in the production system, it is possible to reduce the dimensionality and complexity of the problem, reduce the difficulty of solving the problem, thereby accelerating the solution efficiency of the optimization model and improving the computational efficiency of solving the waste heat recovery and reuse problem in the production system.

[0007] In some embodiments of this application, the step of constructing multiple temperature ranges of the production system based on the thermodynamic measurement data of each process stream, under a preset minimum heat transfer temperature difference constraint, specifically includes: Based on the initial and final temperatures in the thermodynamic measurement data of each process stream, determine the temperature range parameters for each process stream. Based on the minimum heat transfer temperature difference constraint, the temperature range parameters of each process stream are corrected and a temperature range is constructed to obtain the initial temperature range of each process stream. The initial temperature range of each process material is recursively removed and sorted to construct multiple temperature ranges for the production system.

[0008] This application first determines the temperature range parameters of each process stream based on the initial and final temperatures in the thermodynamic measurement data of each process stream. After correcting for the minimum heat transfer temperature difference constraint, the initial temperature range of each process stream is constructed. Then, by removing duplicate values ​​and sorting, multiple temperature ranges of the production system are obtained. This allows for the accurate construction of multiple temperature ranges of the production system, providing a basis for subsequent cascaded calculations using multiple temperature ranges to accelerate the solution calculation efficiency.

[0009] In some embodiments of this application, the step of performing cascaded calculations on the multiple temperature ranges based on the thermal measurement data of each process stream to determine the upper limit of available waste heat of the production system specifically includes: Based on the thermal measurement data of each process logistics, calculate the heat demand for each temperature range. Along the ascending order of the multiple temperature ranges, heat cascading calculations are performed on each temperature range according to its heat demand. The output heat obtained from the cascading calculation of the last temperature range is used as the upper limit of the available waste heat of the production system. During the heat cascading calculation, the first temperature range does not receive external heat input. Each temperature range receives the heat output of the previous adjacent temperature range as heat input, and the remaining heat obtained after satisfying the heat demand of the range is transferred to the next adjacent temperature range as heat output.

[0010] This application first calculates the heat demand for each temperature range based on the thermal measurement data of each process flow. Then, it performs heat cascade calculations sequentially along the ascending order of the multiple temperature ranges. The output heat obtained from the cascade calculation of the last temperature range is used as the upper limit of the available waste heat of the production system. In the heat cascade calculation, the first temperature range does not receive external heat input, and adjacent temperature ranges transfer heat along the ascending order of the numbers. The cascade can enable the ranges to interact with each other, thereby accelerating the efficiency of the range cascade calculation and improving the calculation efficiency of the solution for waste heat recovery and reuse in the production system.

[0011] In some embodiments of this application, the step of using the upper limit of available waste heat as the energy constraint of the production system, aiming to maximize the output flow rates of primary steam, secondary steam, and heat transfer water in the production system, and sequentially constructing and solving optimization models for the output flow rates of primary steam, secondary steam, and heat transfer water, to optimize the output flow rates of primary steam, secondary steam, and heat transfer water, specifically includes: Using the available waste heat upper limit as the first energy constraint and aiming to maximize the output flow rate of primary steam, a first optimization model is constructed and solved to obtain the optimized output flow rate of primary steam. Based on the optimized output flow rate of primary steam, the upper limit of available waste heat is optimized to obtain the first upper limit of remaining available waste heat. Using the first remaining usable waste heat limit as the second energy constraint, and aiming to maximize the output flow rate of the second stage steam, a second optimization model is constructed and solved to obtain the optimized output flow rate of the second stage steam. Based on the optimized output flow rate of secondary steam, the first upper limit of remaining usable waste heat is optimized to obtain the second upper limit of remaining usable waste heat. Using the second remaining usable waste heat upper limit as the third energy constraint, and with the goal of maximizing the output flow rate of hot coal and water, a third optimization model is constructed and solved to obtain the optimized output flow rate of hot coal and water.

[0012] This application first uses the upper limit of available waste heat as the first energy constraint, and constructs a solution to obtain the optimal output flow rate of primary steam with the objective of maximizing the output flow rate of primary steam. Then, using the updated upper limit of available waste heat as the second energy constraint, it constructs a solution to obtain the optimal output flow rate of secondary steam with the objective of maximizing the output flow rate of secondary steam. Finally, using the updated upper limit of available waste heat as the third energy constraint, it constructs a solution to obtain the optimal output flow rate of heat transfer water with the objective of maximizing the output flow rate of heat transfer water. This can decompose the complex problem of waste heat recovery into sub-problems of sequentially optimizing the maximum output flow rates of primary steam, secondary steam, and heat transfer water under the constraint of the upper limit of available waste heat in the production system. This reduces the dimensionality and complexity of the problem, reduces the difficulty of solving the problem, and thus accelerates the solution efficiency of the optimization model, thereby improving the computational efficiency of solving the waste heat recovery and reuse problem in the production system.

[0013] In some embodiments of this application, the step of constructing and solving a first optimization model with the available waste heat upper limit as the first energy constraint and maximizing the production flow rate of the first-stage steam as the objective, to obtain the optimized production flow rate of the first-stage steam, specifically includes: With the goal of maximizing the output flow rate of primary steam, the production thermodynamic process of primary steam is modeled to construct a first optimization function, and the first optimization function and the first energy constraint are combined to obtain a first optimization model; Solving the first optimization model yields the optimal output flow rate of first-stage steam.

[0014] This application first aims to maximize the output flow rate of primary steam by modeling the thermal process of primary steam production. A first optimization model is then obtained by combining this model with a first energy constraint, and subsequently, the optimal output flow rate of primary steam is obtained. By modeling the thermal process of primary steam production, the sub-problem of producing primary steam in the waste heat recovery of the production system can be accurately modeled. Furthermore, by aiming to maximize the output flow rate of primary steam and combining this model with the first energy constraint, an accurate solution can be obtained, thus ensuring the accuracy of the optimal output flow rate of primary steam.

[0015] In some embodiments of this application, the step of constructing and solving a second optimization model with the first remaining usable waste heat upper limit as the second energy constraint and maximizing the secondary steam production flow rate as the objective, to obtain the optimized secondary steam production flow rate, specifically includes: With the goal of maximizing the output flow rate of secondary steam, the production thermodynamic process of the secondary steam is modeled to construct a second optimization function, and the second optimization function and the second energy constraint are combined to obtain a second optimization model; Solve the second optimization model to obtain the optimal output flow rate of the second stage steam.

[0016] This application first aims to maximize the output flow rate of secondary steam by modeling the thermodynamic process of secondary steam production. Then, it combines the second energy constraint to obtain the second optimization model, and finally solves for the optimal output flow rate of secondary steam. By modeling the thermodynamic process of secondary steam production, the sub-problem of secondary steam production in the waste heat recovery of the production system can be accurately modeled. Then, with the goal of maximizing the output flow rate of secondary steam, the second energy constraint can be accurately solved, thus ensuring the accuracy of the optimal output flow rate of secondary steam.

[0017] In some embodiments of this application, the step of constructing and solving a third optimization model with the second remaining usable waste heat upper limit as the third energy constraint and maximizing the output flow rate of the hot coal-water mixture as the objective, to obtain the optimized output flow rate of the hot coal-water mixture, specifically includes: With the goal of maximizing the output flow rate of the heat transfer water, the production thermodynamic process of the heat transfer water is modeled to construct a third optimization function. The third optimization function and the third energy constraint are then combined to obtain a third optimization model. Solving the third optimization model yields the optimized output flow rate of the heat transfer medium water.

[0018] This application first aims to maximize the output flow rate of the heat transfer water by modeling the heat transfer water production thermodynamic process. Combined with the third energy constraint, a third optimization model is obtained, and then the optimal output flow rate of the heat transfer water is solved. By modeling the heat transfer water production thermodynamic process, the sub-problem of producing heat transfer water in the waste heat recovery of the production system can be accurately modeled. Then, with the goal of maximizing the output flow rate of the heat transfer water, the third energy constraint can be used to accurately solve the problem, thereby ensuring the accuracy of the optimal output flow rate of the heat transfer water.

[0019] According to a second aspect of the embodiments of this application, a process industrial production control system based on waste heat recovery optimization is provided, including a temperature range construction module, a range cascade calculation module, a waste heat output optimization module, and a system waste heat recovery module. The temperature range construction module is used to acquire the thermal measurement data of each process material in the production system, and construct multiple temperature ranges of the production system based on the thermal measurement data of each process material under the preset minimum heat transfer temperature difference constraint. The interval cascade calculation module is used to perform cascade calculations on the multiple temperature intervals based on the thermal measurement data of each process material to determine the upper limit of the available waste heat of the production system. The waste heat output optimization module is used to construct and solve optimization models for the output flow rates of primary steam, secondary steam, and heat transfer water of the production system, with the upper limit of available waste heat as the energy constraint of the production system and the goal of maximizing the output flow rates of primary steam, secondary steam, and heat transfer water. The optimized output flow rates of primary steam, secondary steam, and heat transfer water are obtained; wherein, the pressure of primary steam is greater than the pressure of secondary steam. The waste heat recovery module of the system is used to control the production system according to the optimized output flow rates of primary steam, secondary steam and heat transfer water, so as to realize the waste heat recovery of the production system.

[0020] In some embodiments of this application, the temperature range construction module includes a range parameter determination unit, an initial range construction unit, and a range construction processing unit; The interval parameter determination unit is used to determine the temperature interval parameters of each process stream based on the starting temperature and ending temperature in the thermodynamic measurement data of each process stream. The initial interval construction unit is used to modify the temperature interval parameters of each process stream and construct the temperature interval based on the minimum heat transfer temperature difference constraint, so as to obtain the initial temperature interval of each process stream. The interval construction processing unit is used to remove duplicate values ​​and sort the initial temperature intervals of each process material to construct multiple temperature intervals of the production system.

[0021] In some embodiments of this application, the interval cascade calculation module includes an interval heat demand calculation unit and a heat cascade calculation unit; The interval heat demand calculation unit is used to calculate the interval heat demand for each temperature interval based on the thermal measurement data of each process material. The heat cascade calculation unit is used to perform heat cascade calculations for each temperature interval along the ascending order of the multiple temperature interval numbers, based on the heat demand of each temperature interval, and to use the output heat obtained by the cascade calculation of the last temperature interval as the upper limit of the available waste heat of the production system; wherein, during the heat cascade calculation, the first temperature interval does not receive external heat input; each temperature interval receives the heat output of the previous adjacent temperature interval as heat input, and the remaining heat obtained after satisfying the heat demand of the interval is transferred to the next adjacent temperature interval as heat output.

[0022] In some embodiments of this application, the waste heat production optimization module includes a first construction and solution unit, a first waste heat optimization unit, a second construction and solution unit, a second waste heat optimization unit, and a third construction and solution unit; The first construction and solution unit is used to construct and solve the first optimization model with the available waste heat upper limit as the first energy constraint and the goal of maximizing the output flow rate of the first-stage steam, so as to obtain the optimized output flow rate of the first-stage steam. The first waste heat optimization unit is used to optimize the upper limit of available waste heat based on the optimized output flow rate of primary steam to obtain the first remaining available waste heat upper limit. The second construction and solution unit is used to construct and solve the second optimization model with the first remaining available waste heat upper limit as the second energy constraint and the goal of maximizing the output flow rate of the second stage steam, so as to obtain the optimized output flow rate of the second stage steam; The second waste heat optimization unit is used to optimize the first remaining usable waste heat limit based on the optimized output flow rate of the secondary steam to obtain the second remaining usable waste heat limit. The third construction and solution unit is used to construct and solve the third optimization model with the second remaining available waste heat upper limit as the third energy constraint and the goal of maximizing the output flow rate of hot coal and water, so as to obtain the optimized output flow rate of hot coal and water.

[0023] In some embodiments of this application, the first construction solving unit includes a first modeling subunit and a first solving subunit; The first modeling subunit is used to model the production thermodynamic process of the first-stage steam with the goal of maximizing the output flow rate of the first-stage steam, construct a first optimization function, and combine the first optimization function and the first energy constraint to obtain a first optimization model; The first solution subunit is used to solve the first optimization model to obtain the optimized output flow rate of first-stage steam.

[0024] In some embodiments of this application, the second construction solving unit includes a second modeling subunit and a second solving subunit; The second modeling subunit is used to model the production thermodynamic process of the secondary steam with the goal of maximizing the output flow rate of the secondary steam, construct a second optimization function, and combine the second optimization function and the second energy constraint to obtain a second optimization model; The second solution subunit is used to solve the second optimization model to obtain the optimized output flow rate of the second stage steam.

[0025] In some embodiments of this application, the third construction solving unit includes a third modeling subunit and a third solving subunit; The third modeling subunit is used to model the production thermodynamic process of the heat transfer water with the goal of maximizing the output flow rate of the heat transfer water, construct a third optimization function, and combine the third optimization function and the third energy constraint to obtain a third optimization model. The third solution subunit is used to solve the third optimization model to obtain the optimized output flow rate of the heat transfer medium water.

[0026] This application first acquires the thermal measurement data of each process material in the production system, and under the constraint of minimum heat transfer temperature difference, constructs multiple temperature ranges of the production system. Then, it performs cascade calculations on multiple temperature ranges to determine the upper limit of available waste heat in the production system. By constructing multiple temperature ranges and performing cascade calculations, it is possible to accurately calculate the data within each range while enabling interaction between ranges through cascading, thereby accelerating the efficiency of range cascade calculations and improving the computational efficiency of solving the waste heat recovery and reuse problem in the production system. Then, using the upper limit of available waste heat as an energy constraint, and aiming to maximize the output flow rates of primary steam, secondary steam, and heat transfer water in the production system, it sequentially constructs optimization models and solves them to obtain their respective optimized output flow rates. Then, it implements control over the production system. By sequentially decomposing the complex problem of waste heat recovery into sub-problems of sequentially optimizing the maximum output flow rates of primary steam, secondary steam, and heat transfer water under the upper limit of available waste heat in the production system, it is possible to reduce the dimensionality and complexity of the problem, reduce the difficulty of solving the problem, thereby accelerating the solution efficiency of the optimization model and improving the computational efficiency of solving the waste heat recovery and reuse problem in the production system. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of a process industrial production control method based on waste heat recovery optimization, as shown in some embodiments of this application. Figure 2This is a block diagram of a process industrial production control system based on waste heat recovery optimization, as shown in some embodiments of this application. Detailed Implementation

[0028] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below in conjunction with the accompanying drawings are exemplary and are only used to explain some embodiments of this application, and should not be construed as limiting the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments shown in this application without inventive effort are within the protection scope of this application.

[0029] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, unless otherwise explicitly specified, "a plurality of" or "several" means two or more.

[0030] Existing methods for waste heat recovery and reuse, such as traditional integrated thermal analysis methods including pinch analysis or the problem table method, while able to determine minimum utility requirements, struggle to simultaneously consider the coordinated heat extraction of multiple stages of steam and heat transfer fluid. This results in an inability to quickly provide a quantitative distribution of steam production at each stage, limiting the practical application of traditional analytical methods. Therefore, improving the computational efficiency of waste heat recovery and reuse to meet actual production control needs remains a pressing technical problem that needs to be solved.

[0031] Based on the above technical background, please refer to Figure 1 This application provides a process industrial production control method based on waste heat recovery optimization, including steps S101 to S104, each step as follows: Step S101: Obtain the thermal measurement data of each process material in the production system, and construct multiple temperature ranges of the production system based on the thermal measurement data of each process material under the preset minimum heat transfer temperature difference constraint.

[0032] Specifically, the process streams in the production system can be divided into two categories: cold process streams / cold streams and hot process streams / hot streams. Cold streams are streams whose temperature changes from low to high and absorbs heat; hot streams are streams whose temperature changes from high to low and releases heat. In this application, heat exchange occurs between cold and hot streams through heat exchangers / heat exchange networks to achieve waste heat recovery. It is easy to understand that streams used for steam generation and heat transfer water are considered cold streams.

[0033] Specifically, all process logistics in a production system can be summarized into an ordered logistics set. The acquired thermal measurement data of the process stream include: stream type, start temperature (StartT), end temperature (EndT), heat flow rate, and specific heat capacity (SpecificCp).

[0034] In some embodiments of this application, the step of constructing multiple temperature ranges of the production system based on the thermodynamic measurement data of each process stream, under a preset minimum heat transfer temperature difference constraint, specifically includes: Based on the initial and final temperatures in the thermodynamic measurement data of each process stream, determine the temperature range parameters for each process stream. Based on the minimum heat transfer temperature difference constraint, the temperature range parameters of each process stream are corrected and a temperature range is constructed to obtain the initial temperature range of each process stream. The initial temperature range of each process material is recursively removed and sorted to construct multiple temperature ranges for the production system.

[0035] Specifically, after obtaining the thermal measurement data of the process logistics, a logistics data information table is populated and constructed based on the thermal measurement data to build the corresponding temperature ranges. To ensure the effectiveness of subsequent interval cascading, only the logistics data in the range of logistics sequence number [S1~Sm] is populated, where m=n / 2. The specific steps for populating the data table and constructing the temperature ranges are as follows: First, the logistics data in the [Sm~Sn] part is initialized to "NO" using formula (1) so that the logistics data can be gradually filled in according to the calculation conditions in subsequent steps, thereby realizing the calculation of the temperature range of cold and hot logistics.

[0036] (1) in, This is a logistics data information table; For including current logistics A set; This is a conditional control statement; it only applies if the condition is met. The formula containing the conditional control statement is executed at that time; Output the current logistics in the logistics set The order of the items; Output logistics collection The total number of logistics.

[0037] Secondly, by iterating through the following formulas (2)-(6), the temperature range parameters for each process stream are determined. : Using formula (2), from the logistics collection The process logistics in the first half of the logistics aggregate is selected from the cold logistics data information table. The field value is set to 0, where 0 represents cold logistics and 1 represents hot logistics.

[0038] (2) The temperature range parameters of each process stream are obtained using formula (3). Initialize to the starting temperature of the corresponding logistics. .

[0039] (3) Through formula (4), where Fill the corresponding logistics endpoint temperature to The corresponding positions in the sequence are used to achieve temperature mapping and interval coupling between hot and cold logistics, thereby completing the full-process data mapping and interval expansion; in this application, the logistics quantity is exemplarily set to 16, therefore .

[0040] (4) for The initial value of the temperature range for the heat transfer fluid should be based on the minimum heat transfer temperature difference. The virtual temperature is represented below. To ensure the thermodynamic feasibility between hot and cold streams, the virtual temperature of the hot stream usually needs to be corrected. Correction methods include subtracting the initial and final temperatures of the hot stream from the final temperatures. The initial and final temperatures of cold logistics plus Symmetrical correction for hot and cold flows, i.e., adding the initial and final temperatures of the cold flow to... The initial and final temperatures of the hot flow are reduced by Different correction methods do not affect the calculation results; all can ensure the rationality of the heat transfer direction and guarantee that the minimum heat transfer temperature difference constraint is met. Using formulas (5) and (6), the initial and final temperatures of the heat stream are subtracted... The correction method was modified accordingly.

[0041] (5) (6) In actual calculations, there may be situations where temperature ranges between different process materials are equal. To avoid overlapping ranges interfering with subsequent cascaded range and heat balance calculations, it is necessary to remove equal overlapping temperature values. This operation can be accomplished using formulas (7), (8), and (9), where... for The set of renames. The set of renames is constructed using formula (7). .

[0042] (7) in, This indicates that it is not equal to.

[0043] Determine using formula (8) Does the sequence contain duplicate values?

[0044] (8) When formula (8) is satisfied, formula (9) is used to eliminate repeated temperature values.

[0045] (9) To ensure the correctness of the cascaded temperature ranges and the rationality of the heat transfer direction, the temperature ranges need to be sorted in descending order. This can be accomplished using formulas (10)-(13).

[0046] Use formula (10) to determine whether temperature range exchange is necessary.

[0047] (10) When formula (10) is satisfied, formulas (11), (12), and (13) are executed sequentially to complete the temperature range exchange.

[0048] (11) (12) (13) in, This is for temporarily swapping variables.

[0049] Furthermore, after the temperature intervals are constructed, the command "display Temp;" is executed to output the construction results of each temperature interval, thereby determining the position of the last temperature interval and providing a basis for subsequent calculations of the upper limit of available waste heat. It should be noted that when there are n different temperature indices, the corresponding number of temperature intervals is (n-1) to ensure the consistency between interval division and energy balance.

[0050] This application first determines the temperature range parameters of each process stream based on the initial and final temperatures in the thermodynamic measurement data of each process stream. After correcting for the minimum heat transfer temperature difference constraint, the initial temperature range of each process stream is constructed. Then, by removing duplicate values ​​and sorting, multiple temperature ranges of the production system are obtained. This allows for the accurate construction of multiple temperature ranges of the production system, providing a basis for subsequent cascaded calculations using multiple temperature ranges to accelerate the solution calculation efficiency.

[0051] Step S102: Based on the thermal measurement data of each process material, perform cascade calculations on the multiple temperature ranges to determine the upper limit of available waste heat of the production system.

[0052] In some embodiments of this application, the step of performing cascaded calculations on the multiple temperature ranges based on the thermal measurement data of each process stream to determine the upper limit of available waste heat of the production system specifically includes: Based on the thermal measurement data of each process logistics, calculate the heat demand for each temperature range. Along the ascending order of the multiple temperature ranges, heat cascading calculations are performed on each temperature range according to its heat demand. The output heat obtained from the cascading calculation of the last temperature range is used as the upper limit of the available waste heat of the production system. During the heat cascading calculation, the first temperature range does not receive external heat input. Each temperature range receives the heat output of the previous adjacent temperature range as heat input, and the remaining heat obtained after satisfying the heat demand of the range is transferred to the next adjacent temperature range as heat output.

[0053] Specifically, the heat demand for each temperature range is determined by calculating the heat load of each cold and hot fluid within the range; the specific steps for determining the heat demand for each temperature range are as follows: First, the heat load of the cold flow in each temperature range is initialized using formulas (14) and (15). and heat load of hot logistics The cold flow between the two temperature ranges is determined by formula (16).

[0054] (14) (15) (16) Secondly, after initialization, the heat load of cold flow and heat flow in each temperature range is calculated using formulas (17), (18), and (19).

[0055] (17) (18) (19) Finally, using formula (20), the heat load of cold and hot streams in each temperature range is converted into the heat deficit of the corresponding temperature range, i.e., the heat demand of the range. .

[0056] (20) Specifically, assuming the production system has no heat loss or dissipation and satisfies overall energy conservation, after calculating the heat demand for each temperature range, the heat input for each temperature range is then... and regional heat demand The heat output can then be calculated. It then transfers its heat output to the next adjacent temperature range; the first temperature range does not receive external heat input. Each temperature interval is calculated sequentially in ascending order of its serial number. During the calculation, the heat output of the previous adjacent temperature interval is used as the heat input, and the remaining heat obtained after meeting the heat demand of the interval is used as the heat output and transferred to the next adjacent temperature interval as the heat input of the next adjacent temperature interval. This completes the heat transfer, i.e., "cascading". This cascading calculation process can be described by formulas (21) and (22).

[0057] (twenty one) (twenty two) Through the above steps, a complete code model for the problem table method can be established. After determining the temperature range, the heat supply / demand of each process stream within each temperature range is determined by the corresponding process stream's heat capacity flow rate, specific heat capacity, and the temperature difference within the corresponding temperature range. Therefore, the heat output obtained in the last temperature range through cascaded calculations is not a fixed value but an optimizable variable. Thus, the heat output of the last temperature range can be minimized to obtain the upper limit of available waste heat for the current production system. Simultaneously, because the last temperature range... The obtained heat output corresponds to the heat that the system needs to discharge into the environment or cooling medium in the problem table method or interval cascade. Therefore, minimizing the heat output of the last temperature interval is equivalent to recovering as much heat internally as possible under the premise of satisfying the minimum heat transfer temperature difference constraint and thermal balance, thereby minimizing the external cooling load. Formula (23) can describe the objective function of minimization optimization, which is used to determine the optimal energy utilization state of the production system under the minimum heat transfer temperature difference constraint, and provides a theoretical basis and boundary conditions for the subsequent optimization of primary steam, secondary steam and heat transfer medium water in the production system.

[0058] (twenty three) This application first calculates the heat demand for each temperature range based on the thermal measurement data of each process flow. Then, it performs heat cascade calculations sequentially along the ascending order of the multiple temperature ranges. The output heat obtained from the cascade calculation of the last temperature range is used as the upper limit of the available waste heat of the production system. In the heat cascade calculation, the first temperature range does not receive external heat input, and adjacent temperature ranges transfer heat along the ascending order of the numbers. The cascade can enable the ranges to interact with each other, thereby accelerating the efficiency of the range cascade calculation and improving the calculation efficiency of the solution for waste heat recovery and reuse in the production system.

[0059] Step S103: Using the available waste heat upper limit as the energy constraint of the production system, and with the goal of maximizing the output flow rates of the primary steam, secondary steam, and heat transfer water of the production system, construct and solve optimization models for the output flow rates of the primary steam, secondary steam, and heat transfer water in sequence, optimize the output flow rates of the primary steam, secondary steam, and heat transfer water, and obtain the optimized output flow rates of the primary steam, secondary steam, and heat transfer water; wherein, the pressure of the primary steam is greater than the pressure of the secondary steam.

[0060] Specifically, to facilitate calculations and model calls, the data from the original logistics data information table was organized into a new logistics information data table. In; among them, This indicates different grades or categories of working fluids, including: low-pressure steam, referring to steam with a pressure of 1.0 MPa, i.e., secondary steam, including... Three temperature zones; medium-pressure steam, referring to steam with a pressure of 3.5 MPa, i.e., first-stage steam, including... Three temperature zones; and, heat transfer medium water ; This represents a set of temperature parameters, indicating the initial temperature of each grade of steam and heat transfer water. and endpoint temperature .

[0061] Specifically, to map the new logistics data table to multiple predefined temperature ranges for easier subsequent calculations, it is necessary to compare the set of temperature parameters with multiple temperature ranges to determine the corresponding position of each level of steam within the temperature range; among these, using The relative positions of different grades of steam within the temperature range are marked; the specific steps to achieve the mapping are as follows: Formula (24) is used to determine whether the steam temperature falls within a certain temperature range.

[0062] (twenty four) When the condition of formula (24) is met, the steam temperature is considered to fall within the current temperature range. Then, the relative position of the steam of this grade is marked based on the current temperature range using formula (25).

[0063] (25) Finally, to ensure that the production system does not consume additional thermal utilities, the thermal utility quantity is fixed as a constant value using formula (26) to avoid the introduction of additional heat input; where, the suffix This indicates that the currently selected variable is fixed. ;suffix This represents the value of the currently selected variable obtained from the previous solution.

[0064] (26) In some embodiments of this application, the step of using the upper limit of available waste heat as the energy constraint of the production system, aiming to maximize the output flow rates of primary steam, secondary steam, and heat transfer water in the production system, and sequentially constructing and solving optimization models for the output flow rates of primary steam, secondary steam, and heat transfer water, to optimize the output flow rates of primary steam, secondary steam, and heat transfer water, specifically includes: Using the available waste heat upper limit as the first energy constraint and aiming to maximize the output flow rate of primary steam, a first optimization model is constructed and solved to obtain the optimized output flow rate of primary steam. Based on the optimized output flow rate of primary steam, the upper limit of available waste heat is optimized to obtain the first upper limit of remaining available waste heat. Using the first remaining usable waste heat limit as the second energy constraint, and aiming to maximize the output flow rate of the second stage steam, a second optimization model is constructed and solved to obtain the optimized output flow rate of the second stage steam. Based on the optimized output flow rate of secondary steam, the first upper limit of remaining usable waste heat is optimized to obtain the second upper limit of remaining usable waste heat. Using the second remaining usable waste heat upper limit as the third energy constraint, and with the goal of maximizing the output flow rate of hot coal and water, a third optimization model is constructed and solved to obtain the optimized output flow rate of hot coal and water.

[0065] Specifically, since the production process of all steam is divided into three stages—preheating, vaporization, and superheating—each stage corresponds to a different temperature zone, and the specific heat of each stage is set to a constant value, to ensure the accuracy of heat calculation, each stage of each stage of steam needs to be calculated independently when optimizing each stage of steam. The specific steps for optimizing the first-stage steam are as follows: First, the cascading calculations for each stage of the first-stage steam are completed using formulas (27)-(30); among which, This indicates the heat capacity flow rate for producing first-stage steam, expressed in t / h. This refers to the specific heat or equivalent specific heat of the corresponding stage. , , These represent the process stream sets corresponding to different stages of primary steam generation; 4.18 is the coefficient for converting kcal to kJ; 10 / 3600 represents the conversion... The coefficient for converting t / h to t / s, and then to MW: Using formula (27), standard cascade calculations are applied to all temperature zones except those with primary steam.

[0066] (27) Using formula (28), cascade calculations are performed in the Middle1 temperature zone. Additional heat is required for the steam preheating stage during the calculation, with a corresponding temperature rise of (242-80).

[0067] (28) Using formula (29), cascade calculations are performed in the Middle2 temperature zone. Since the vaporization stage is theoretically latent heat and the phase change temperature remains basically unchanged, the equivalent specific heat method is used in the calculation (the temperature difference of 1℃ is taken for calculation), and the heat consumption of the interval corresponding to the latent heat of vaporization is deducted.

[0068] (29) Using formula (30), cascade calculations are performed in the Middle3 temperature zone. Additional heat is required for the steam superheating stage during the calculation, with a corresponding temperature rise of (253-243).

[0069] (30) Then, in order to ensure that the heat load consumed in producing primary steam does not exceed the upper limit of available waste heat, the corresponding energy constraint condition is expressed by formula (31) to ensure the energy conservation and thermal balance stability of the system.

[0070] (31) Finally, with the goal of maximizing the output flow rate of primary steam, the first optimization function is constructed as formula (32). By solving the first optimization function, the optimized output flow rate of primary steam can be obtained.

[0071] (32) Specifically, the steps to optimize the upper limit of available waste heat based on the optimized output flow rate of primary steam are as follows: First, update the original logistics data information table using formulas (33), (34), and (35).

[0072] (33) (34) (35) Next, re-execute formulas (14)-(20) and formula (23) to optimize the system again and obtain the corrected upper limit of available residual heat, that is, the first upper limit of available residual heat.

[0073] Specifically, the steps for optimizing the second-stage steam are basically the same as those for optimizing the first-stage steam, and the specific steps for optimizing the second-stage steam are as follows: First, the cascading calculations for each stage of the secondary steam are completed using formulas (36)-(39); among which, The heat capacity flow rate for producing secondary steam is expressed in t / h; the temperature rise in the preheating stage corresponding to the Low1 temperature zone is (179-80°C); the temperature rise in the superheating stage corresponding to the Low3 temperature zone is (190-180°C). (36) (37) (38) (39) Then, to ensure that the heat load consumed in producing secondary steam does not exceed the upper limit of available waste heat, the corresponding energy constraint condition is expressed by formula (40).

[0074] (40) Finally, with the goal of maximizing the output flow rate of secondary steam, a second optimization function is constructed as formula (41). By solving the second optimization function, the optimized output flow rate of secondary steam can be obtained.

[0075] (41) Specifically, the steps to optimize the upper limit of available waste heat based on the optimized output flow rate of secondary steam are as follows: First, update the original logistics data information table using formulas (42), (43), and (44).

[0076] (42) (43) (44) Next, re-execute formulas (14)-(20) and formula (23) to optimize the system again and obtain the corrected upper limit of available residual heat, that is, the second upper limit of available residual heat.

[0077] Specifically, the steps for optimizing the heat transfer fluid are as follows: First, the cascade calculations for each stage of the heat transfer medium are completed using formulas (45), (46), and (47). Formulas (45) and (46) divide the temperature zone into the ordinary temperature zone corresponding to formula (45) and the temperature zone where the heat transfer medium is located, respectively. When formula (45) is satisfied, standard cascade calculation is performed according to formula (21).

[0078] (45) When formula (46) is satisfied, cascade calculation is performed according to formula (47). During the calculation, additional heat required for the heating medium water to rise is needed; among which, This indicates the heat capacity flow rate of the heat-generating medium water, in units of t / h; the corresponding temperature rise is (100-50).

[0079] (46) (47) Then, to ensure that the heat load consumed by the production of heat transfer medium does not exceed the upper limit of available waste heat, the corresponding energy constraint condition is expressed by formula (48).

[0080] (48) Finally, with the goal of maximizing the output flow rate of the heat transfer medium water, a third optimization function is constructed as formula (49). By solving the third optimization function, the optimized output flow rate of the heat transfer medium water can be obtained.

[0081] (49) This application first uses the upper limit of available waste heat as the first energy constraint, and constructs a solution to obtain the optimal output flow rate of primary steam with the objective of maximizing the output flow rate of primary steam. Then, using the updated upper limit of available waste heat as the second energy constraint, it constructs a solution to obtain the optimal output flow rate of secondary steam with the objective of maximizing the output flow rate of secondary steam. Finally, using the updated upper limit of available waste heat as the third energy constraint, it constructs a solution to obtain the optimal output flow rate of heat transfer water with the objective of maximizing the output flow rate of heat transfer water. This can decompose the complex problem of waste heat recovery into sub-problems of sequentially optimizing the maximum output flow rates of primary steam, secondary steam, and heat transfer water under the constraint of the upper limit of available waste heat in the production system. This reduces the dimensionality and complexity of the problem, reduces the difficulty of solving the problem, and thus accelerates the solution efficiency of the optimization model, thereby improving the computational efficiency of solving the waste heat recovery and reuse problem in the production system.

[0082] In some embodiments of this application, the step of constructing and solving a first optimization model with the available waste heat upper limit as the first energy constraint and maximizing the production flow rate of the first-stage steam as the objective, to obtain the optimized production flow rate of the first-stage steam, specifically includes: With the goal of maximizing the output flow rate of primary steam, the production thermodynamic process of primary steam is modeled to construct a first optimization function, and the first optimization function and the first energy constraint are combined to obtain a first optimization model; Solving the first optimization model yields the optimal output flow rate of first-stage steam.

[0083] This application first aims to maximize the output flow rate of primary steam by modeling the thermal process of primary steam production. A first optimization model is then obtained by combining this model with a first energy constraint, and subsequently, the optimal output flow rate of primary steam is obtained. By modeling the thermal process of primary steam production, the sub-problem of producing primary steam in the waste heat recovery of the production system can be accurately modeled. Furthermore, by aiming to maximize the output flow rate of primary steam and combining this model with the first energy constraint, an accurate solution can be obtained, thus ensuring the accuracy of the optimal output flow rate of primary steam.

[0084] In some embodiments of this application, the step of constructing and solving a second optimization model with the first remaining usable waste heat upper limit as the second energy constraint and maximizing the secondary steam production flow rate as the objective, to obtain the optimized secondary steam production flow rate, specifically includes: With the goal of maximizing the output flow rate of secondary steam, the production thermodynamic process of the secondary steam is modeled to construct a second optimization function, and the second optimization function and the second energy constraint are combined to obtain a second optimization model; Solve the second optimization model to obtain the optimal output flow rate of the second stage steam.

[0085] This application first aims to maximize the output flow rate of secondary steam by modeling the thermodynamic process of secondary steam production. Then, it combines the second energy constraint to obtain the second optimization model, and finally solves for the optimal output flow rate of secondary steam. By modeling the thermodynamic process of secondary steam production, the sub-problem of secondary steam production in the waste heat recovery of the production system can be accurately modeled. Then, with the goal of maximizing the output flow rate of secondary steam, the second energy constraint can be accurately solved, thus ensuring the accuracy of the optimal output flow rate of secondary steam.

[0086] In some embodiments of this application, the step of constructing and solving a third optimization model with the second remaining usable waste heat upper limit as the third energy constraint and maximizing the output flow rate of the hot coal-water mixture as the objective, to obtain the optimized output flow rate of the hot coal-water mixture, specifically includes: With the goal of maximizing the output flow rate of the heat transfer water, the production thermodynamic process of the heat transfer water is modeled to construct a third optimization function. The third optimization function and the third energy constraint are then combined to obtain a third optimization model. Solving the third optimization model yields the optimized output flow rate of the heat transfer medium water.

[0087] This application first aims to maximize the output flow rate of the heat transfer water by modeling the heat transfer water production thermodynamic process. Combined with the third energy constraint, a third optimization model is obtained, and then the optimal output flow rate of the heat transfer water is solved. By modeling the heat transfer water production thermodynamic process, the sub-problem of producing heat transfer water in the waste heat recovery of the production system can be accurately modeled. Then, with the goal of maximizing the output flow rate of the heat transfer water, the third energy constraint can be used to accurately solve the problem, thereby ensuring the accuracy of the optimal output flow rate of the heat transfer water.

[0088] Step S104: Control the production system according to the optimized output flow rates of primary steam, secondary steam and heat transfer water to achieve waste heat recovery of the production system.

[0089] Specifically, after completing the cascade calculations and waste heat output optimization, the calculation results are organized into a set of operational target parameters and output to the production system. The organized calculation results include, but are not limited to: heat curves and distributions for each temperature range; upper limits of available waste heat and corresponding boundary values; optimized output flow rates of primary and secondary steam and equivalent cooling load parameters for each temperature zone stage; optimized output flow rates of heat transfer water and corresponding temperature zone locations and heat consumption; temperature zone boundaries consistent with the minimum heat transfer temperature difference constraint; steam temperature zone marking parameters; and the cascaded available waste heat distribution order from high to low.

[0090] Specifically, after receiving the set of operating target parameters, the production system maps the set of operating target parameters to adjustable controllable quantities / operating instructions on site, including steam production instructions, heat transfer medium water heat extraction instructions, and waste heat distribution instructions.

[0091] More specifically, before issuing instructions, the operational feasibility must be verified, including: verifying that the total heat consumption of steam and heat transfer water at each level does not exceed the upper limit of available waste heat; verifying that the heat cascading of key temperature zones is non-negative to avoid local deficits that would require additional external heat input to the system; and verifying that the equipment capacity boundaries meet the requirements for instruction execution.

[0092] More specifically, after the command is issued and executed, the operating results, including steam output, heat transfer water flow rate, key point temperature, and changes in cooling load, need to be recorded. The energy-saving effect is evaluated using the reduction in cooling side exhaust heat load / steam replacement / heat transfer water replacement as indicators, and consistency verification is performed. When the operating conditions such as load, raw material properties, and ambient temperature change, causing the deviation to exceed the threshold, the command needs to be recalculated and updated. The latest operating conditions are periodically collected, cascade calculations and waste heat production optimization are repeatedly performed, and the set of operating target parameters is updated to update the operating command, so as to achieve continuous online operation optimization.

[0093] Compared to existing technologies, this application first acquires the thermal measurement data of each process material in the production system, and constructs multiple temperature ranges of the production system under the constraint of minimum heat transfer temperature difference. Then, it performs cascade calculations on multiple temperature ranges to determine the upper limit of available waste heat in the production system. By constructing multiple temperature ranges and performing cascade calculations, it can accurately calculate the data within each range while enabling interaction between ranges through cascading, thereby accelerating the efficiency of range cascade calculations and improving the computational efficiency of solving the waste heat recovery and reuse problem in the production system. Then, using the upper limit of available waste heat as an energy constraint, and aiming to maximize the output flow rates of primary steam, secondary steam, and heat transfer water in the production system, it sequentially constructs optimization models and solves them to obtain their respective optimized output flow rates. Then, it implements control over the production system. By sequentially decomposing the complex problem of waste heat recovery into sub-problems of sequentially optimizing the maximum output flow rates of primary steam, secondary steam, and heat transfer water under the upper limit of available waste heat in the production system, it can reduce the problem dimensionality and complexity, reduce the difficulty of solving the problem, thereby accelerating the solution efficiency of the optimization model and improving the computational efficiency of solving the waste heat recovery and reuse problem in the production system.

[0094] For a method corresponding to the one described above, please refer to [link to relevant documentation]. Figure 2 The present application provides a process industrial production control system based on waste heat recovery optimization, including a temperature range construction module 210, a range cascade calculation module 220, a waste heat output optimization module 230 and a system waste heat recovery module 240. The temperature range construction module 210 is used to acquire the thermal measurement data of each process material in the production system, and construct multiple temperature ranges of the production system based on the thermal measurement data of each process material under the preset minimum heat transfer temperature difference constraint. The interval cascade calculation module 220 is used to perform cascade calculations on the multiple temperature intervals based on the thermal measurement data of each process material to determine the upper limit of the available waste heat of the production system. The waste heat output optimization module 230 is used to construct and solve optimization models for the output flow rates of primary steam, secondary steam, and heat transfer water in the production system, with the upper limit of available waste heat as the energy constraint of the production system and the goal of maximizing the output flow rates of primary steam, secondary steam, and heat transfer water. The optimized output flow rates of primary steam, secondary steam, and heat transfer water are obtained. The pressure of primary steam is greater than that of secondary steam. The waste heat recovery module 240 is used to control the production system based on the optimized output flow rates of primary steam, secondary steam, and heat transfer water to achieve waste heat recovery from the production system.

[0095] In some embodiments of this application, the temperature range construction module 210 includes a range parameter determination unit, an initial range construction unit, and a range construction processing unit; The interval parameter determination unit is used to determine the temperature interval parameters of each process stream based on the starting temperature and ending temperature in the thermodynamic measurement data of each process stream. The initial interval construction unit is used to modify the temperature interval parameters of each process stream and construct the temperature interval based on the minimum heat transfer temperature difference constraint, so as to obtain the initial temperature interval of each process stream. The interval construction processing unit is used to remove duplicate values ​​and sort the initial temperature intervals of each process material to construct multiple temperature intervals of the production system.

[0096] In some embodiments of this application, the interval cascade calculation module 220 includes an interval heat demand calculation unit and a heat cascade calculation unit; The interval heat demand calculation unit is used to calculate the interval heat demand for each temperature interval based on the thermal measurement data of each process material. The heat cascade calculation unit is used to perform heat cascade calculations for each temperature interval along the ascending order of the multiple temperature interval numbers, based on the heat demand of each temperature interval, and to use the output heat obtained by the cascade calculation of the last temperature interval as the upper limit of the available waste heat of the production system; wherein, during the heat cascade calculation, the first temperature interval does not receive external heat input; each temperature interval receives the heat output of the previous adjacent temperature interval as heat input, and the remaining heat obtained after satisfying the heat demand of the interval is transferred to the next adjacent temperature interval as heat output.

[0097] In some embodiments of this application, the waste heat production optimization module 230 includes a first construction and solution unit, a first waste heat optimization unit, a second construction and solution unit, a second waste heat optimization unit, and a third construction and solution unit; The first construction and solution unit is used to construct and solve the first optimization model with the available waste heat upper limit as the first energy constraint and the goal of maximizing the output flow rate of the first-stage steam, so as to obtain the optimized output flow rate of the first-stage steam. The first waste heat optimization unit is used to optimize the upper limit of available waste heat based on the optimized output flow rate of primary steam to obtain the first remaining available waste heat upper limit. The second construction and solution unit is used to construct and solve the second optimization model with the first remaining available waste heat upper limit as the second energy constraint and the goal of maximizing the output flow rate of the second stage steam, so as to obtain the optimized output flow rate of the second stage steam; The second waste heat optimization unit is used to optimize the first remaining usable waste heat limit based on the optimized output flow rate of the secondary steam to obtain the second remaining usable waste heat limit. The third construction and solution unit is used to construct and solve the third optimization model with the second remaining available waste heat upper limit as the third energy constraint and the goal of maximizing the output flow rate of hot coal and water, so as to obtain the optimized output flow rate of hot coal and water.

[0098] In some embodiments of this application, the first construction solving unit includes a first modeling subunit and a first solving subunit; The first modeling subunit is used to model the production thermodynamic process of the first-stage steam with the goal of maximizing the output flow rate of the first-stage steam, construct a first optimization function, and combine the first optimization function and the first energy constraint to obtain a first optimization model; The first solution subunit is used to solve the first optimization model to obtain the optimized output flow rate of first-stage steam.

[0099] In some embodiments of this application, the second construction solving unit includes a second modeling subunit and a second solving subunit; The second modeling subunit is used to model the production thermodynamic process of the secondary steam with the goal of maximizing the output flow rate of the secondary steam, construct a second optimization function, and combine the second optimization function and the second energy constraint to obtain a second optimization model; The second solution subunit is used to solve the second optimization model to obtain the optimized output flow rate of the second stage steam.

[0100] In some embodiments of this application, the third construction solving unit includes a third modeling subunit and a third solving subunit; The third modeling subunit is used to model the production thermodynamic process of the heat transfer water with the goal of maximizing the output flow rate of the heat transfer water, construct a third optimization function, and combine the third optimization function and the third energy constraint to obtain a third optimization model. The third solution subunit is used to solve the third optimization model to obtain the optimized output flow rate of the heat transfer medium water.

[0101] This application first acquires the thermal measurement data of each process material in the production system, and under the constraint of minimum heat transfer temperature difference, constructs multiple temperature ranges of the production system. Then, it performs cascade calculations on multiple temperature ranges to determine the upper limit of available waste heat in the production system. By constructing multiple temperature ranges and performing cascade calculations, it is possible to accurately calculate the data within each range while enabling interaction between ranges through cascading, thereby accelerating the efficiency of range cascade calculations and improving the computational efficiency of solving the waste heat recovery and reuse problem in the production system. Then, using the upper limit of available waste heat as an energy constraint, and aiming to maximize the output flow rates of primary steam, secondary steam, and heat transfer water in the production system, it sequentially constructs optimization models and solves them to obtain their respective optimized output flow rates. Then, it implements control over the production system. By sequentially decomposing the complex problem of waste heat recovery into sub-problems of sequentially optimizing the maximum output flow rates of primary steam, secondary steam, and heat transfer water under the upper limit of available waste heat in the production system, it is possible to reduce the dimensionality and complexity of the problem, reduce the difficulty of solving the problem, thereby accelerating the solution efficiency of the optimization model and improving the computational efficiency of solving the waste heat recovery and reuse problem in the production system.

[0102] It should be understood that the system provided in this application corresponds to the aforementioned method. The process industrial production control system based on waste heat recovery optimization provided in this application can realize the process industrial production control method based on waste heat recovery optimization provided in any one of the embodiments of this application.

[0103] Adaptively, embodiments of this application also provide a computer device and a computer-readable storage medium.

[0104] The computer device includes: a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor; The processor executes the computer program to implement a process industrial production control method based on waste heat recovery optimization according to this application.

[0105] The computer-readable storage medium stores multiple instructions adapted for loading by a processor to execute a process industrial production control method based on waste heat recovery optimization according to this application.

[0106] The above description represents some embodiments of this application, providing a further detailed explanation of the purpose, technical solution, and beneficial effects of this application. It should be understood that the above-described embodiments of this application should not be construed as limiting this application. In particular, any changes, modifications, equivalent substitutions, and variations made by those skilled in the art within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A process industrial production control method based on waste heat recovery optimization, characterized in that, include: Acquire thermal measurement data of each process material in the production system, and construct multiple temperature ranges of the production system based on the thermal measurement data of each process material under the preset minimum heat transfer temperature difference constraint. Based on the thermal measurement data of each process material, cascade calculations are performed on the multiple temperature ranges to determine the upper limit of available waste heat of the production system. Using the available waste heat upper limit as the energy constraint of the production system, and aiming to maximize the output flow rates of primary steam, secondary steam, and heat transfer water in the production system, optimization models for the output flow rates of primary steam, secondary steam, and heat transfer water are constructed and solved sequentially. The output flow rates of primary steam, secondary steam, and heat transfer water are optimized to obtain the optimized output flow rates of primary steam, secondary steam, and heat transfer water; wherein, the pressure of primary steam is greater than the pressure of secondary steam. The production system is controlled based on the optimized output flow rates of primary steam, secondary steam, and heat transfer water to achieve waste heat recovery.

2. The process industrial production control method based on waste heat recovery optimization according to claim 1, characterized in that, Based on the thermal measurement data of each process material, and under a preset minimum heat transfer temperature difference constraint, multiple temperature ranges of the production system are constructed, specifically including: Based on the initial and final temperatures in the thermodynamic measurement data of each process stream, determine the temperature range parameters for each process stream. Based on the minimum heat transfer temperature difference constraint, the temperature range parameters of each process stream are corrected and a temperature range is constructed to obtain the initial temperature range of each process stream. The initial temperature range of each process material is recursively removed and sorted to construct multiple temperature ranges for the production system.

3. The process industrial production control method based on waste heat recovery optimization according to claim 1, characterized in that, The step of determining the upper limit of usable waste heat of the production system by cascading calculations on the multiple temperature ranges based on the thermal measurement data of each process flow specifically includes: Based on the thermal measurement data of each process logistics, calculate the heat demand for each temperature range. Along the ascending order of the multiple temperature ranges, heat cascading calculations are performed on each temperature range according to its heat demand. The output heat obtained from the cascading calculation of the last temperature range is used as the upper limit of the available waste heat of the production system. During the heat cascading calculation, the first temperature range does not receive external heat input. Each temperature range receives the heat output of the previous adjacent temperature range as heat input, and the remaining heat obtained after satisfying the heat demand of the range is transferred to the next adjacent temperature range as heat output.

4. The process industrial production control method based on waste heat recovery optimization according to claim 1, characterized in that, The production system is constrained by the available waste heat limit. To maximize the output flow rates of primary steam, secondary steam, and heat transfer water, optimization models for the output flow rates of primary steam, secondary steam, and heat transfer water are constructed and solved sequentially. This process optimizes the output flow rates of primary steam, secondary steam, and heat transfer water, yielding the optimized output flow rates. Specifically, this includes: Using the available waste heat upper limit as the first energy constraint and aiming to maximize the output flow rate of primary steam, a first optimization model is constructed and solved to obtain the optimized output flow rate of primary steam. Based on the optimized output flow rate of primary steam, the upper limit of available waste heat is optimized to obtain the first upper limit of remaining available waste heat. Using the first remaining usable waste heat limit as the second energy constraint, and aiming to maximize the output flow rate of the second stage steam, a second optimization model is constructed and solved to obtain the optimized output flow rate of the second stage steam. Based on the optimized output flow rate of secondary steam, the first upper limit of remaining usable waste heat is optimized to obtain the second upper limit of remaining usable waste heat. Using the second remaining usable waste heat upper limit as the third energy constraint, and with the goal of maximizing the output flow rate of hot coal and water, a third optimization model is constructed and solved to obtain the optimized output flow rate of hot coal and water.

5. The process industrial production control method based on waste heat recovery optimization according to claim 4, characterized in that, The first optimization model, which uses the available waste heat upper limit as the first energy constraint and aims to maximize the output flow rate of the first-stage steam, is constructed and solved to obtain the optimized output flow rate of the first-stage steam. Specifically, this includes: With the goal of maximizing the output flow rate of primary steam, the production thermodynamic process of primary steam is modeled to construct a first optimization function, and the first optimization function and the first energy constraint are combined to obtain a first optimization model; Solving the first optimization model yields the optimal output flow rate of first-stage steam.

6. The process industrial production control method based on waste heat recovery optimization according to claim 4, characterized in that, The process of constructing and solving a second optimization model, using the upper limit of the first remaining usable waste heat as the second energy constraint and aiming to maximize the output flow rate of the second-stage steam, to obtain the optimized output flow rate of the second-stage steam, specifically includes: With the goal of maximizing the output flow rate of secondary steam, the production thermodynamic process of the secondary steam is modeled to construct a second optimization function, and the second optimization function and the second energy constraint are combined to obtain a second optimization model; Solve the second optimization model to obtain the optimal output flow rate of the second stage steam.

7. The process industrial production control method based on waste heat recovery optimization according to claim 4, characterized in that, The third optimization model, which uses the second remaining usable waste heat upper limit as the third energy constraint and aims to maximize the output flow rate of the hot coal-water mixture, is constructed and solved to obtain the optimized output flow rate of the hot coal-water mixture. Specifically, this includes: With the goal of maximizing the output flow rate of the heat transfer water, the production thermodynamic process of the heat transfer water is modeled to construct a third optimization function. The third optimization function and the third energy constraint are then combined to obtain a third optimization model. Solving the third optimization model yields the optimized output flow rate of the heat transfer medium water.

8. A process industrial production control system based on waste heat recovery optimization, characterized in that, It includes a temperature range construction module, a range cascade calculation module, a waste heat output optimization module, and a system waste heat recovery module; The temperature range construction module is used to acquire the thermal measurement data of each process material in the production system, and construct multiple temperature ranges of the production system based on the thermal measurement data of each process material under the preset minimum heat transfer temperature difference constraint. The interval cascade calculation module is used to perform cascade calculations on the multiple temperature intervals based on the thermal measurement data of each process material to determine the upper limit of the available waste heat of the production system. The waste heat output optimization module is used to construct and solve optimization models for the output flow rates of primary steam, secondary steam, and heat transfer water of the production system, with the upper limit of available waste heat as the energy constraint of the production system and the goal of maximizing the output flow rates of primary steam, secondary steam, and heat transfer water. The optimized output flow rates of primary steam, secondary steam, and heat transfer water are obtained; wherein, the pressure of primary steam is greater than the pressure of secondary steam. The waste heat recovery module of the system is used to control the production system according to the optimized output flow rates of primary steam, secondary steam and heat transfer water, so as to realize the waste heat recovery of the production system.

9. A process industrial production control system based on waste heat recovery optimization according to claim 8, characterized in that, The temperature range construction module includes a range parameter determination unit, an initial range construction unit, and a range construction processing unit; The interval parameter determination unit is used to determine the temperature interval parameters of each process stream based on the starting temperature and ending temperature in the thermodynamic measurement data of each process stream. The initial interval construction unit is used to modify the temperature interval parameters of each process stream and construct the temperature interval based on the minimum heat transfer temperature difference constraint, so as to obtain the initial temperature interval of each process stream. The interval construction processing unit is used to remove duplicate values ​​and sort the initial temperature intervals of each process material to construct multiple temperature intervals of the production system.

10. A process industrial production control system based on waste heat recovery optimization according to claim 8, characterized in that, The interval cascaded calculation module includes an interval heat demand calculation unit and a heat cascaded calculation unit; The interval heat demand calculation unit is used to calculate the interval heat demand for each temperature interval based on the thermal measurement data of each process material. The heat cascade calculation unit is used to perform heat cascade calculations for each temperature interval along the ascending order of the multiple temperature interval numbers, based on the heat demand of each temperature interval, and to use the output heat obtained by the cascade calculation of the last temperature interval as the upper limit of the available waste heat of the production system; wherein, during the heat cascade calculation, the first temperature interval does not receive external heat input; each temperature interval receives the heat output of the previous adjacent temperature interval as heat input, and the remaining heat obtained after satisfying the heat demand of the interval is sent as heat output to the next adjacent temperature interval.

Images