A method for managing supply and demand of materials in a sugar processing process

Abstract

The application discloses a kind of material supply and demand balance management methods in sugar processing process, specifically related to production process management technical field, to solve the core problem that evaporation process hammer degree fixed value control is disjointed with crystallization process demand in prior art, cannot give consideration to material supply and demand balance, capacity utilization and energy consumption optimization, the application first constructs the weighted multi-objective optimization function of fusion material supply and demand deviation, crystallization capacity utilization, evaporation unit energy consumption;In the hammer degree safety interval of preset crystallization process, iterate candidate discharge hammer degree, account the crystallization feed demand in set time window, evaluate corresponding evaporation supply capacity and eliminate infeasible scheme, determine the optimal discharge target hammer degree of evaporation by optimization function solution;Finally, with optimal hammer degree as set value, according to actual discharge hammer degree deviation, real-time adjust live steam valve opening degree, the application realizes the dynamic cooperation of evaporation and crystallization process, guarantees production stability, gives consideration to capacity improvement and energy saving.

Description

Technical Field

[0001] This invention relates to the field of production process management technology, and more specifically, to a method for managing the supply and demand balance of materials in a sugar processing process. Background Technology

[0002] In sugar processing, such as sugarcane sugar production and beet sugar production, evaporation is the core process for sugar concentration. Its function is to concentrate the purified dilute syrup to a high-concentration syrup that meets the requirements of the crystallization process. The saturation of the evaporated syrup is the core parameter that determines the operating status of the crystallization process.

[0003] In actual production, the matching degree between the syrup hammer pressure and the crystallization process directly determines the production efficiency: if the syrup hammer pressure is too low, the crystallization process needs to evaporate a large amount of water, which leads to a significant extension of the single tank crystallization cycle, insufficient crystallization capacity, continuous backlog of material from the front-end evaporation process, and disruption of the entire production rhythm; if the syrup hammer pressure is too high, the syrup viscosity increases sharply, making it difficult for crystal nuclei to form, reducing the crystallization rate, and even causing problems such as pseudo-crystals and sticking to the tank, which seriously affects the quality of the finished sugar and the crystallization efficiency.

[0004] In current sugar production, the control of syrup hammer weight in the evaporation process only involves adjusting the discharge hammer weight at a fixed value within the evaporation stage itself, which has the following technical drawbacks: Firstly, the coordination between upstream and downstream processes is poor, making it impossible to achieve dynamic balance between material supply and demand. The existing control mode separates the evaporation process and the crystallization process as two independent control units. The setpoint of the evaporation process is mostly based on static calibration based on production experience, without linkage matching with the real-time operating status of the downstream crystallization process, the feeding plan of the sub-tank, and the dynamic feeding demand. It is impossible to achieve dynamic balance between evaporation supply capacity and crystallization feeding demand. When the feeding demand of the crystallization process fluctuates, it is very easy to cause excessive evaporation output, resulting in syrup accumulation and production rhythm disorder, or insufficient syrup supply, resulting in the crystallization process waiting for material and stopping. This seriously restricts the continuous and stable operation of the sugar production line. Secondly, the hammer degree control target is singular and cannot take into account both crystallization capacity and product quality. The existing fixed value control mode cannot dynamically optimize the output hammer degree according to the real-time capacity utilization status of the crystallization process, and it is difficult to avoid the two-way technical contradiction of insufficient capacity caused by low hammer degree and quality abnormality caused by high hammer degree. Third, the evaporation process is not included in the energy consumption optimization target, making it impossible to meet the production needs of energy conservation and consumption reduction. The evaporation process is the core steam consumption unit in sugar production, accounting for the majority of the total steam consumption of the entire plant. It is the core control link for energy conservation and consumption reduction in the sugar industry. However, the existing technology only takes the achievement of the desired evaporation temperature as the core control target and does not include the unit energy consumption of the evaporation process as an optimization dimension in the control system. It is impossible to achieve optimal energy consumption control of the evaporation process under the premise of meeting the material supply and demand balance and crystallization capacity requirements. This results in high steam consumption during the production process, which is not in line with the green, low-carbon, energy-saving and consumption-reducing development trend of the sugar industry.

[0005] To address the above problems, this invention proposes a method for managing the supply and demand balance of materials in the sugar processing process. Summary of the Invention

[0006] In order to overcome the above-mentioned defects of the prior art, embodiments of the present invention provide a method for managing the supply and demand balance of materials in the sugar processing process.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A method for managing the supply and demand balance of materials in a sugar processing process, comprising: Step 1: Construct a weighted multi-objective optimization function value by combining supply and demand balance, capacity utilization rate, and evaporation energy consumption; Step 2: Within the preset safe range of hammer weight in the crystallization process, and in combination with the set step size, traverse all candidate discharge hammer weights, calculate the feed demand of the crystallization process within the current set time window, and then evaluate the supply capacity of the evaporation process under different candidate discharge hammer weights. Finally, use the multi-objective optimization function value to solve the problem and determine the optimal discharge target hammer weight of the evaporation process under different candidate discharge hammer weights. Step 3: Based on the optimal discharge target hammer weight obtained from the solution of the evaporation process, the target set value is used as the actual discharge hammer weight as the process value. The deviation is calculated and a correction signal is output to adjust the opening of the live steam valve in real time.

[0008] Specifically, the weighted multi-objective optimization function value; function value ; in This indicates the total volume of qualified syrup that the evaporation process can provide within the set time window; The total volume of qualified syrup required for the crystallization process within a set time window; This refers to the capacity utilization rate of the crystallization process; This refers to the energy consumption per unit of syrup evaporation in the evaporation process. , as well as These are preset weighting coefficients, and their sum is one.

[0009] Specifically, calculate the feed requirements for the crystallization process within the current set time window; Obtain the feeding time distribution and instantaneous flow rate of the crystallizer corresponding to the waiting feeding period and the feeding period; The set time window is divided into various time nodes. The feed flow rate of each crystallizer is superimposed on the corresponding time node according to the planned feed time and feed duration to obtain the crystallization feed demand flow rate curve at the time node level within the window. The total feed volume of qualified syrup required for the crystallization process within the window is obtained by summing the feed flow rates at all time points within the window.

[0010] Specifically, each online crystallizer is classified into different states, including the waiting period for feeding, the feeding period, the nucleation period, the crystal growth period, and the discharging period. Set feeding permissions associated with different states; feeding permissions include allow feeding, feeding in progress, and prohibit feeding; Calculate the feed requirements for crystallizers in the waiting-to-feed and feeding periods; The calculation process is as follows: The formula is expressed as follows ; Let be the planned feed volume for the i-th crystallizer in a single run; Let i be the effective volume of the i-th crystallizer; The optimal filling rate preset for the crystallization tank; Let represent the remaining material in the i-th crystallizer.

[0011] Specifically, the logic for obtaining capacity utilization rate; According to the formula Calculate the predicted total sugar production within a future time window. ; in For syrup density, For candidate discharge hammer height, This refers to the sugar extraction rate during crystallization. Divide the predicted total sugar production by the set time window duration to obtain the predicted sugar production rate; Dividing the predicted sugar production rate by the preset rated sugar production rate of the crystallization process yields the capacity utilization rate of the crystallization process. .

[0012] Specifically, the supply capacity of the evaporation process under different candidate discharge hammers is evaluated; Calculate the water evaporation rate per unit time for different candidate discharge hammer heights; use the formula ;in Given the candidate temperature, this represents the mass of water that the evaporation system needs to evaporate per unit time. The mass flow rate of the diluted syrup feed per unit time; For real-time feeding of diluted syrup, use a hammer mill. Given the current candidate discharge hammer pressure; then, at the candidate hammer pressure, the stable output volumetric flow rate of qualified syrup per unit time by the evaporation system. ; For each candidate heat value, check whether it is within the evaporation supply capacity range of the evaporation system; if a candidate heat value exceeds the evaporation supply capacity range, it is directly eliminated. For each group of candidate discharge hammers within the evaporation supply capacity range, the total qualified syrup discharge volume that the evaporation process can provide within a set time window is determined. ; To set a time window.

[0013] Specifically, the testing process; Based on a preset heat transfer coefficient, and adjusted using the cleaning interval, the real-time heat transfer coefficient is output; real-time heat transfer coefficient ; The preset heat transfer coefficient, To utilize the scaling factor derived from the cleaning interval duration, a mapping rule between the cleaning interval duration and the scaling factor is pre-built to determine the scaling factor. ; Based on the law of conservation of heat, calculate the maximum amount of water evaporated per unit time of the evaporation system under the current operating conditions; That is, through the formula and To obtain the maximum evaporation rate ; Let A be the maximum heat transfer per unit time, and A be the total heat exchange area of ​​the evaporation system. This represents the total effective heat transfer temperature difference under the current operating conditions. Here, r is the preset heat loss coefficient, and r is the latent heat of vaporization of live steam. The testing process is as follows: If ≥ If the candidate hammer is within the evaporation supply capacity range, then it is determined that the candidate hammer is within the evaporation supply capacity range; otherwise, if... > If the candidate hammer degree exceeds the evaporation supply capacity range, then it is determined that the candidate hammer degree exceeds the evaporation supply capacity range.

[0014] Specifically, the optimal discharge target hammer weight; Calculate the unit evaporation energy consumption for each group of candidate discharge hammers within the evaporation supply capacity range. ; To set the cumulative consumption of live steam within a set time window, Set the cumulative amount of water evaporated by the evaporation system within the set time window; Calculate the function value F corresponding to each candidate discharge hammer degree, and select the candidate discharge hammer degree that minimizes the F value as the optimal discharge target hammer degree.

[0015] Specifically, the opening degree of the live steam valve is adjusted; The target setpoint is compared with the process value. If the process value is less than the target setpoint, the output correction signal is to increase the opening; otherwise, the output correction signal is to decrease the opening. Obtain the target evaporation rate corresponding to the target setpoint and the process value, respectively; Calculate the difference between the target evaporation rates of the two values ​​and use it as the scheduling value; Establish a mapping rule for the steam valve opening degree corresponding to the scheduling value under different correction signals. After transformation using the mapping rule, the steam valve opening degree corresponding to the correction signal is obtained. The opening degree of the live steam valve matched by the correction signal is used as the opening command, and the adjustment is made based on the current opening degree of the live steam valve.

[0016] The technical effects and advantages of this invention are as follows: This invention achieves dynamic and precise matching of supply and demand in the evaporation and crystallization processes. By classifying the online crystallizer's status throughout the entire cycle and controlling its feeding permissions, it calculates the planned feeding volume for a single tank and generates node-level feeding demand flow curves within a time window. This enables refined quantification of the feeding demand for the crystallization process. Simultaneously, it evaluates the supply capacity of the evaporation process under different hammer degrees and eliminates infeasible solutions by combining hammer degree safety range constraints. With supply and demand balance as the core optimization dimension, it effectively avoids problems such as syrup backlog, waiting for materials and shutdown, and extended crystallization cycles and product quality defects caused by abnormal hammer degrees. This significantly improves the continuity, stability, and controllability of the entire sugar production line. This invention constructs a multi-dimensional collaborative optimization system, achieving a balance between crystallization capacity release and evaporation energy consumption control. It can flexibly adapt to the differentiated needs of different production scenarios. By integrating a weighted multi-objective optimization function that combines material supply and demand deviation, capacity utilization rate, and unit evaporation energy consumption, the weight coefficients can be dynamically adjusted according to production modes such as peak season capacity, normal balance, and off-season energy consumption priority. At the same time, the real-time heat transfer coefficient is corrected based on the cleaning interval, and the maximum supply capacity of the evaporation system is calculated. This ensures that the optimization objectives are deeply matched with the actual operating conditions of the equipment. While ensuring that the rated capacity of the crystallization process is fully utilized, it achieves refined control of evaporation steam consumption, effectively reduces production energy consumption, helps sugar manufacturing enterprises reduce costs and increase efficiency, and meets the industry's requirements for green and low-carbon development. Attached Figure Description

[0017] Figure 1 This is a flowchart of a material supply and demand balance management method in the sugar processing process according to the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] like Figure 1 As shown, a material supply and demand balance management method in the sugar processing process is as follows: Step 1: Construct a weighted multi-objective optimization function value by combining supply and demand balance, capacity utilization rate, and evaporation energy consumption; The formula is expressed as follows: function value ; in This indicates the total volume of qualified syrup that the evaporation process can provide within the set time window; The total volume of qualified syrup required for the crystallization process within a set time window; This refers to the capacity utilization rate of the crystallization process; This refers to the energy consumption per unit of syrup evaporation in the evaporation process. Before substituting into the formula for calculation, The calculated absolute difference as well as Standardize the process.

[0020] , as well as These are preset weighting coefficients, and their sum is one.

[0021] Based on the sugar processing production mode settings, the sugar processing production mode includes peak season capacity mode, regular balance mode and off-season energy consumption priority mode. Each pattern group corresponds to a set of weight coefficient values.

[0022] For example, under the peak season production-first model; =0.5, =0.35, =0.15.

[0023] Step 2: Within the preset safe range of hammer weight in the crystallization process, and in combination with the set step size, traverse all candidate discharge hammer weights, calculate the feed demand of the crystallization process within the current set time window, and then evaluate the supply capacity of the evaporation process under different candidate discharge hammer weights. Finally, use the multi-objective optimization function value to solve the problem and determine the optimal discharge target hammer weight of the evaporation process under different candidate discharge hammer weights. The hammer pressure safety range can be set to , The minimum allowable hammer weight for crystallization to prevent insufficient production capacity. The maximum permissible hammer weight for crystallization without difficulty is determined by process testing, and a fixed boundary is established.

[0024] Specifically: Each online crystallizer is classified into different states, including the waiting period for feeding, the feeding period, the nucleation period, the crystal growth period, and the discharge period. Set feeding permissions associated with different states; feeding permissions include allow feeding, feeding in progress, and prohibit feeding; Additional notes: During the waiting period for material delivery, the material delivery permission is set to allow delivery. The feeding permission during the feeding period is currently in progress. During the nucleation period, crystal growth period, and material feeding period, feeding is prohibited.

[0025] Calculate the feed requirements for crystallizers in the waiting-to-feed and feeding periods; The calculation process is as follows: The formula is expressed as ; Let be the planned feed volume for the i-th crystallizer in a single run; Let be the effective volume of the i-th crystallizer; derived from equipment design drawings and on-site calibration, a fixed value. The optimal filling rate preset for the crystallizer; for example, 60% for intermittent crystallizers and 75% for continuous crystallizers, determined by the process specification. The remaining material in the i-th crystallizer is calculated from the real-time liquid level and effective volume. Additional explanation, if If the calculation result is negative, then 0 is taken, meaning that there is no feeding requirement for this tank. If the calculation result exceeds the remaining feeding volume of a single tank, the remaining feeding volume is taken as the upper limit to avoid feeding overflow.

[0026] Obtain the feeding time distribution and instantaneous flow rate of the crystallizer corresponding to the waiting feeding period and the feeding period; Planned material feeding time determination: If there is a clear MES production plan, the material feeding start time given in the plan shall be executed; if there is no clear plan, it shall be calculated as "the completion time of the previous batch of material feeding + the fixed time for washing the tank". The washing time is fixed at 5~10 minutes according to the process specification. Determination of feeding time and instantaneous flow rate: The feeding time for a single tank is fixed according to the process specifications to avoid excessive disturbance inside the tank due to feeding too quickly; Instantaneous feed flow rate per tank: ,in Given the single tank feeding time (in hours), the constant instantaneous flow rate during the feeding period is calculated.

[0027] The set time window is divided into various time nodes. The feed flow rate of each crystallizer is superimposed on the corresponding time node according to the planned feed time and feed duration to obtain the crystallization feed demand flow rate curve at the time node level within the window. Additional notes: Only when the feeding time period overlaps with the set window will it be counted as a valid feeding.

[0028] The total feed flow rate at all time points within the window is summed to obtain the total qualified syrup feed volume required for the crystallization process within the window. That is, the total feed volume of qualified syrup , For time step, The total instantaneous feed flow rate at node j is obtained by superimposing the feed flow rates of all crystallizers at node j.

[0029] At the same time, according to the formula Calculate the predicted total sugar production within a future time window. ; in For syrup density, For candidate discharge hammer height, This refers to the sugar extraction rate from crystallization (typically 85%~90% in the sugar industry, a fixed value determined by the process specifications). Divide the predicted total sugar production by the set time window duration to obtain the predicted sugar production rate; Dividing the predicted sugar production rate by the preset rated sugar production rate of the crystallization process yields the capacity utilization rate of the crystallization process. ; Additional explanation, if ,Pick =1.

[0030] Calculate the water evaporation rate per unit time for different candidate discharge hammer heights; use the formula ; in The value represents the mass of water that the evaporation system needs to evaporate per unit time under the candidate temperature, expressed in kg / h. The mass flow rate of the diluted syrup feed per unit time is expressed in kg / h. For real-time feeding of diluted syrup, use a hammer mill. The current candidate discharge hammer height; Under the candidate saturation level, the evaporation system can stably output the qualified syrup volumetric flow rate per unit time (converted to volume units based on syrup density). ; For each candidate evaporation rate, check whether it is within the evaporation supply capacity range of the evaporation system; avoid outputting a supply capacity value that is theoretically feasible but practically unattainable. If a candidate evaporator exceeds the evaporation supply capacity, it will be eliminated directly. Based on the preset heat transfer coefficient, the real-time heat transfer coefficient is output after adjustment using the cleaning interval time (i.e., the continuous running time of the heat exchange tube after the last acid washing). Real-time heat transfer coefficient ; The heat transfer coefficient preset by the equipment manufacturer. The scaling factor is used to convert the cleaning interval duration. A mapping rule between cleaning interval duration and scaling factor is pre-built, that is, each set of duration intervals corresponding to the cleaning interval duration is set, and each set of duration intervals corresponds to a scaling factor; the scaling factor is limited to the range of 0.94-1, which is initially set by technical personnel and can be dynamically adjusted later. The shorter the cleaning interval duration, the higher the probability of matching 1. The scaling factor is obtained by matching the cleaning interval with the corresponding time range. ; During operation, scale (sugar and ash buildup) gradually forms on the inner wall of the heat exchange tubes of the evaporator, leading to increased thermal resistance and decreased heat transfer efficiency.

[0031] Based on the law of conservation of heat, calculate the maximum amount of water evaporated per unit time of the evaporation system under the current operating conditions; That is, through the formula and To obtain the maximum evaporation rate ; Let A be the maximum heat transfer per unit time, and A be the total heat exchange area of ​​the evaporation system. This represents the total effective heat transfer temperature difference under the current operating conditions. The preset heat loss coefficient (fixed value 0.98) is r, which is the latent heat of vaporization of live steam (obtained from the steam table). ;in The total theoretical heat transfer temperature difference of the evaporation system is the ideal maximum temperature difference without any loss. This is the total ineffective temperature difference loss of the evaporation system, which is the sum of all temperature difference losses that cannot be used for water evaporation; ;in and These represent the saturation temperatures of the first-effect heating steam and the secondary steam produced by the final-effect evaporation, respectively; obtained from the "Properties of Saturated Steam" table. ; This is due to the loss from the increase in total boiling point; This refers to the total pipeline resistance loss; This represents the total hydrostatic pressure loss of the liquid column. The boiling point of sucrose solution is higher than that of pure water under the same pressure. The difference is called the boiling point elevation. The higher the temperature, the greater the boiling point elevation. This part of the temperature difference is used to raise the boiling point of the syrup and cannot be used for water evaporation. It is the most significant ineffective loss in sugar production evaporation. For the i-th effect evaporator, the sugar solution hammer value is marked as The boiling point increases at atmospheric pressure (101.325 kPa). ; According to Dühring's rule (the boiling point of a solution is linearly related to the boiling point of pure water under the same pressure), the boiling point elevation under the i-th effective actual operation is calculated as follows: ; Operating pressure of the i-th effect evaporator ; Elevation of boiling point for each effect Summation yields ; Calculated; where For single-effect pipeline temperature loss, take 1℃ / effect for well-insulated pipelines and 2℃ / effect for general insulation, which is a fixed value calibrated by the factory; N is the total number of effects; the N-effect evaporation system has N−1 sections of secondary steam pipelines, so multiply by (N−1); The pressure at half the height of the liquid column is taken as the average pressure. The hydrostatic equation is: Average pressure of the liquid layer. ;in The absolute operating pressure of the liquid surface in the i-th effect evaporator. Let be the density of the i-th effective sugar solution, and g be the acceleration due to gravity. This refers to the height of the static liquid layer inside the evaporator. Retrieving the saturated water vapor table, we obtain the following results: The corresponding pure water saturation temperature, The corresponding pure water saturation temperature, using The saturation temperature of pure water minus The corresponding pure water saturation temperature is used to obtain the temperature difference loss of a single-effect liquid column. The total hydrostatic pressure loss of the liquid column is obtained by summing the temperature difference losses of each liquid column. The total boiling point elevation loss of the hydrostatic column is obtained by multiplying the boiling point elevation of the single-effect hydrostatic column by the total number of effects; The boiling point elevation of a single-effect static liquid column is limited to 0.5-1℃ / effect and can be ignored in engineering calculations. If it is a rising film / forced circulation evaporation, the value is 0.5℃ / effect.

[0032] The testing process is as follows: If ≥ If the candidate hammer is within the evaporation supply capacity range, then it is determined that the candidate hammer is within the evaporation supply capacity range; otherwise, if... > If the candidate discharge hammer thickness exceeds the evaporation supply capacity range, then the total qualified syrup discharge volume that the evaporation process can provide within a set time window is determined. ; To set a time window; Calculate the unit evaporation energy consumption for each group of candidate discharge hammers within the evaporation supply capacity range. ; The cumulative consumption of live steam within a set time window (the total mass of boiler live steam consumed by the evaporation system for a given candidate discharge hammer). Set the cumulative amount of water evaporated by the evaporation system within the set time window; Calculate the function value F corresponding to each candidate discharge hammer degree, and select the candidate discharge hammer degree that minimizes the F value as the optimal discharge target hammer degree. Additional notes: The output should also show the discharge flow rate corresponding to the optimal target discharge hammer weight. .

[0033] The constraints under the optimal discharge target hammer weight are verified: Hammering safety constraint: The optimal discharge target hammering must be within the hammering safety range; End-to-end material balance constraint: The sum of the total qualified syrup output volume that the evaporation process can provide and the maximum schedulable storage capacity of the buffer tank must be higher than the total qualified syrup feed volume required by the crystallization process; Safety constraints for evaporation equipment operation: live steam pressure, vacuum degree of each effect, feed flow rate, and liquid level in the tank are all within the equipment's design rated range; Crystallization process operation constraints: The feed flow rate shall not exceed the maximum feed flow rate designed for the crystallizer; Peak demand coverage constraint: steady-state evaporation discharge flow rate + maximum feed flow rate of buffer tank ≥ peak flow rate of crystallization feed.

[0034] Step 3: Based on the optimal discharge target hammer weight obtained from the solution of the evaporation process, the target set value is used as the target value. The actual discharge hammer weight is detected as the process value. The deviation is calculated and a correction signal is output to adjust the opening of the live steam valve in real time. Specifically: The target setpoint is compared with the process value. If the process value is less than the target setpoint, a correction signal is output to increase the opening degree. This indicates that the amount of evaporated water is insufficient, so the opening degree of the live steam valve is increased to improve the evaporation rate. Conversely, the output correction signal is a signal to reduce the opening degree; reducing the opening degree of the live steam valve to avoid exceeding the limit. Obtain the target evaporation rate corresponding to the target setpoint and process value, respectively; substitute the target setpoint and process value into the formula. China The calculation was obtained by substitution; Calculate the difference between the target evaporation rates of the two values ​​and use it as the scheduling value; Establish a mapping rule for the steam valve opening degree corresponding to the scheduling value under different correction signals. After transformation using the mapping rule, the steam valve opening degree corresponding to the correction signal is obtained. That is, under different correction signals, the scheduling value corresponds to each group of scheduling value intervals, and each group of scheduling value intervals corresponds to a steam valve opening degree; The live steam opening matched under the increased opening signal is taken as the opening increment, and the live steam opening matched under the decreased opening signal is taken as the opening decrement.

[0035] The opening degree of the live steam valve matched by the correction signal is used as the opening command, and the adjustment is made based on the current opening degree of the live steam valve. Additional notes: The optimal discharge target hammer pressure is simultaneously sent to the technicians, who then adjust the operating parameters, including but not limited to the frequency of the total feed regulating valve / feed pump, the opening degree of the first-effect live steam regulating valve, the opening degree of the last-effect vacuum system regulating valve, the opening degree of the feed distribution regulating valves for each effect, and the status of the condensate / non-condensable gas discharge valve.

[0036] The above formulas are all dimensionless calculations. Dimensionless calculations can be performed using various methods such as standardization, which will not be elaborated here. The formulas are derived from software simulations based on a large amount of collected data, and the preset parameters in the formulas can be set by those skilled in the art according to the actual situation.

[0037] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more sets of available media. The available medium can be a magnetic medium (e.g., floppy disk, ATA hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. The semiconductor medium can be a solid-state ATA hard disk.

[0038] It should be understood that in the various embodiments of this application, the order of the above-mentioned processes does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0039] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0040] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0041] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0042] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0043] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable ATA hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0044] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for managing the supply and demand balance of materials in a sugar processing process, characterized in that, include: Step 1: Construct a weighted multi-objective optimization function value by combining supply and demand balance, capacity utilization rate, and evaporation energy consumption; Step 2: Within the preset safe range of hammer weight in the crystallization process, and in combination with the set step size, traverse all candidate discharge hammer weights, calculate the feed demand of the crystallization process within the current set time window, and then evaluate the supply capacity of the evaporation process under different candidate discharge hammer weights. Finally, use the multi-objective optimization function value to solve the problem and determine the optimal discharge target hammer weight of the evaporation process under different candidate discharge hammer weights. Step 3: Based on the optimal discharge target hammer weight obtained from the solution of the evaporation process, the target set value is used as the actual discharge hammer weight as the process value. The deviation is calculated and a correction signal is output to adjust the opening of the live steam valve in real time.

2. The material supply and demand balance management method in the sugar processing process according to claim 1, characterized in that: Weighted multi-objective optimization function value; function value ; in This indicates the total volume of qualified syrup that the evaporation process can provide within the set time window; The total volume of qualified syrup required for the crystallization process within a set time window; This refers to the capacity utilization rate of the crystallization process; This refers to the energy consumption per unit of syrup evaporation in the evaporation process. , as well as These are preset weighting coefficients, and their sum is one.

3. The material supply and demand balance management method in the sugar processing process according to claim 2, characterized in that: Calculate the feed requirements for the crystallization process within the current set time window; Obtain the feeding time distribution and instantaneous flow rate of the crystallizer corresponding to the waiting feeding period and the feeding period; The set time window is divided into various time nodes. The feed flow rate of each crystallizer is superimposed on the corresponding time node according to the planned feed time and feed duration to obtain the crystallization feed demand flow rate curve at the time node level within the window. The total feed volume of qualified syrup required for the crystallization process within the window is obtained by summing the feed flow rates at all time points within the window.

4. The material supply and demand balance management method in the sugar processing process according to claim 3, characterized in that: Each online crystallizer is classified into different states, including the waiting period for feeding, the feeding period, the nucleation period, the crystal growth period, and the discharge period. Set the feeding permissions associated with different states; Feeding permissions include Allow Feeding, Feeding in Progress, and Prohibit Feeding; Calculate the feed requirements for crystallizers in the waiting-to-feed and feeding periods; The calculation process is as follows: The formula is expressed as follows ; Let be the planned feed volume for the i-th crystallizer in a single run; Let i be the effective volume of the i-th crystallizer; The optimal filling rate preset for the crystallization tank; Let represent the remaining material in the i-th crystallizer.

5. The material supply and demand balance management method in the sugar processing process according to claim 4, characterized in that: Logic for obtaining capacity utilization rate; According to the formula Calculate the predicted total sugar production within a future time window. ; in For syrup density, For candidate discharge hammer height, To improve the sugar extraction rate during crystallization Divide the predicted total sugar production by the set time window duration to obtain the predicted sugar production rate; Dividing the predicted sugar production rate by the preset rated sugar production rate of the crystallization process yields the capacity utilization rate of the crystallization process. .

6. The material supply and demand balance management method in the sugar processing process according to claim 5, characterized in that: Evaluate the supply capacity of the evaporation process under different candidate discharge hammer pressures; Calculate the water evaporation rate per unit time for different candidate discharge hammer heights; use the formula ;in Given the candidate temperature, this represents the mass of water that the evaporation system needs to evaporate per unit time. The mass flow rate of the diluted syrup feed per unit time; For real-time feeding of diluted syrup, use a hammer mill. Given the current candidate discharge hammer pressure; then, at the candidate hammer pressure, the stable output volumetric flow rate of qualified syrup per unit time by the evaporation system. ; For each candidate heat value, check whether it is within the evaporation supply capacity range of the evaporation system; if a candidate heat value exceeds the evaporation supply capacity range, it is directly eliminated. For each group of candidate discharge hammers within the evaporation supply capacity range, the total qualified syrup discharge volume that the evaporation process can provide within a set time window is determined. ; To set a time window.

7. The material supply and demand balance management method in sugar processing according to claim 6, characterized in that: Inspection process; Based on the preset heat transfer coefficient, the real-time heat transfer coefficient is output after adjustment using the cleaning interval time. Real-time heat transfer coefficient ; The preset heat transfer coefficient, The scaling factor is used to convert the cleaning interval duration. The scaling factor is determined by pre-establishing a mapping rule between the cleaning interval duration and the scaling factor. ; Based on the law of conservation of heat, calculate the maximum amount of water evaporated per unit time of the evaporation system under the current operating conditions; That is, through the formula and To obtain the maximum evaporation rate ; Let A be the maximum heat transfer per unit time, and A be the total heat exchange area of ​​the evaporation system. This represents the total effective heat transfer temperature difference under the current operating conditions. Here, r is the preset heat loss coefficient, and r is the latent heat of vaporization of live steam. The testing process is as follows: If ≥ If the candidate hammer is within the evaporation supply capacity range, then it is determined that the candidate hammer is within the evaporation supply capacity range; otherwise, if... > If the candidate hammer degree exceeds the evaporation supply capacity range, then it is determined that the candidate hammer degree exceeds the evaporation supply capacity range.

8. The material supply and demand balance management method in the sugar processing process according to claim 7, characterized in that: Optimal discharge target hammer weight; Calculate the unit evaporation energy consumption for each group of candidate discharge hammers within the evaporation supply capacity range. ; To set the cumulative consumption of live steam within a set time window, Set the cumulative amount of water evaporated by the evaporation system within the set time window; Calculate the function value F corresponding to each candidate discharge hammer degree, and select the candidate discharge hammer degree that minimizes the F value as the optimal discharge target hammer degree.

9. A method for managing material supply and demand balance in sugar processing according to claim 8, characterized in that: Adjusting the opening degree of the live steam valve; The target setpoint is compared with the process value. If the process value is less than the target setpoint, the output correction signal is to increase the opening; otherwise, the output correction signal is to decrease the opening. Obtain the target evaporation rate corresponding to the target setpoint and the process value, respectively; Calculate the difference between the target evaporation rates of the two values ​​and use it as the scheduling value; Establish a mapping rule for the steam valve opening degree corresponding to the scheduling value under different correction signals. After transformation using the mapping rule, the steam valve opening degree corresponding to the correction signal is obtained. The opening degree of the live steam valve matched by the correction signal is used as the opening command, and the adjustment is made based on the current opening degree of the live steam valve.

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