Energy-saving rice flour drying and sterilization integrated production control method

Abstract

The application relates to food production control technology and discloses an energy-saving rice flour drying and sterilization integrated production control method, which comprises the following steps: collecting production state data and calculating a current rice flour water content estimation value, a water removal amount and a sterilization action amount to be supplemented, determining whether to enter a cooperative control interval according to a first water content threshold and a second water content threshold, calculating a surface overdrying risk value after entering the interval and linkage controlling a wet exhaust channel discharge amount, a drying chamber internal circulating air proportion, a conveying belt running speed and a sterilization output, calculating a wet exhaust energy efficiency evaluation value after a sterilization standard exit interval to determine whether to increase or decrease the wet exhaust action until resetting. The current rice flour water content and the sterilization action amount are determined to enter the cooperative interval through calculation, the wet exhaust and sterilization mechanisms are linkage controlled based on the surface overdrying risk value, the system can adjust the action according to the material body state, the sterilization efficiency is considered on the premise of preventing surface hardening, and the late wet exhaust energy consumption is reduced.

Description

Technical Field

[0001] This invention relates to food production control technology, specifically an energy-saving integrated production control method for drying and sterilizing rice noodles. Background Technology

[0002] On a continuous rice noodle production line, drying and sterilization are fundamental processes to ensure product quality. Existing rice noodle production control methods typically divide the drying chamber into multiple sections and control the ambient temperature and humidity of each section according to a set process curve. During production line operation, conventional control systems collect ambient temperature and humidity data to adjust the output of the heat source and the operating frequency of the dehumidification fan, thereby promoting rice noodle dehydration and achieving the desired hygiene standards.

[0003] This control method relies primarily on closed-loop regulation of environmental parameters within the drying chamber, lacking calculation of changes in the rice flour's physical state. This prevents the system from adjusting its actions based on the actual moisture content of the rice flour and the cumulative sterilization effect. In actual production, to achieve a faster dehydration rate, the control program often maintains a high exhaust flow rate. This strong dehydration can cause the surface moisture of the rice flour to evaporate too quickly, resulting in hardening and crusting, hindering the migration of internal moisture. Simultaneously, premature surface drying disrupts the suitable humid and hot environment for sterilization, requiring the system to rely on supplemental heating after dehydration to complete sterilization, adding extra processing time. Furthermore, in the later stages of dehydration, the exhaust's ability to remove moisture decreases; continuing the high-intensity dehydration will directly expel a large amount of hot air that has not reached saturation moisture content from the drying chamber, resulting in ineffective heat loss.

[0004] Existing control methods sever the coupling between drying / dehydration and sterilization, failing to maintain suitable surface moisture levels for rice noodles while simultaneously ensuring sterilization efficiency and dehumidification efficiency. Therefore, establishing a coordinated control method based on the moisture content of rice noodles and the sterilization progress, capable of completing sterilization while preventing surface hardening and crusting and reducing overall system energy consumption, is a problem that needs to be solved in this field. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an energy-saving integrated production control method for drying and sterilizing rice noodles. This method solves the problems of existing control methods that sever the coupling relationship between drying and sterilization, resulting in hardening and crusting of the rice noodle surface, low energy efficiency in dehumidification during the later stages of dehydration, and high overall energy consumption of the system.

[0006] To address the above problems, the present invention provides the following technical solution: This invention provides an energy-saving integrated production control method for drying and sterilizing rice flour, employing the following technical solution: An energy-saving integrated production control method for drying and sterilizing rice noodles includes the following steps: Collect production status data during the rice noodle drying and sterilization process; Based on the production status data, the estimated current moisture content of the rice noodles, the amount of moisture to be removed, and the amount of sterilization to be replenished are calculated. Based on the preset first moisture content threshold and the preset second moisture content threshold, combined with the current estimated moisture content of rice noodles and the amount of sterilization to be supplemented, it is determined whether to enter the collaborative control range; Once the system determines that the system has entered the collaborative control zone, the risk value of excessive surface dryness is quantitatively calculated, and based on the risk value of excessive surface dryness, the system controls the discharge volume of the dehumidification channel, the proportion of circulating air inside the drying chamber, the speed of the conveyor belt, and the output of the sterilization actuator. When the amount of sterilization to be replenished reaches the preset amount requirement, but the amount of moisture to be removed does not reach the preset moisture standard, the coordinated control zone is exited, the dehumidification energy efficiency evaluation value is calculated, and the dehumidification action is increased or decreased until both the amount of moisture to be removed and the amount of sterilization to be replenished reach the preset target range, and then each actuator is reset to the material discharge standby condition.

[0007] By adopting the above technical solution, the controlled object is expanded from simply the temperature and humidity of the drying room to include the estimated current moisture content of the rice noodles, the amount of moisture to be removed, and the amount of sterilization to be replenished. This allows the control system to adjust the drying and sterilization actions according to the state of the rice noodles themselves. After the rice noodles enter the coordinated control zone, the strong dehumidification action is limited based on the amount of sterilization to be replenished, and the discharge rate of the dehumidification channel and the proportion of circulating air inside the drying room are controlled in conjunction with the risk value of excessive surface dryness. This ensures that the main sterilization process is completed while the rice noodles still have a suitable moisture content, reducing the need for repeated heating and additional residence time required for post-drying sterilization.

[0008] Once the required amount of sterilization is achieved, the system switches to dehydration control. The amount of dehumidification is adjusted based on the dehumidification energy efficiency assessment value, reducing heat loss from exhaust ventilation and lowering energy consumption per unit product. This control method establishes interconnected control conditions based on moisture content stage, amount of moisture to be removed, required amount of sterilization, risk of excessive surface dryness, and dehumidification energy consumption. This adapts to changes in raw material moisture content, powder coating, ambient humidity, and conveying load, improving the stability of continuous production processes.

[0009] Further steps for collecting production status data during the rice noodle drying and sterilization process include: The production status data is read synchronously, including air thermodynamic status data, pneumatic and valve control status data, energy input and material conveying status data, and online moisture content and sterilization output status data. The air thermodynamic state data includes inlet air temperature, return air temperature, exhaust air temperature, inlet air relative humidity, return air relative humidity, and exhaust air relative humidity. The pneumatic and valve control status data includes the frequency of the circulating fan, the frequency of the exhaust fan, the actual exhaust air volume, the opening degree of the exhaust valve, and the opening degree of the circulating air valve. The energy input and material conveying status data include heat source output, energy consumption per unit time of the production line, and the speed of the conveyor belt. The online moisture content and sterilization output status data include the online moisture content detection value of rice noodles and the output of the sterilization actuator. The physical position of the rice noodles is obtained by integrating the conveyor belt speed at the feeding time and the current sampling time, and the cumulative residence time of the rice noodles is calculated.

[0010] By adopting the above technical solution, the control system establishes a spatiotemporal record of the rice noodles inside the continuous drying chamber based on the synchronously read production status data and the physical location and cumulative residence time of the rice noodles obtained through integral calculation. This method provides a physical parameter basis for subsequently adjusting drying and sterilization actions at specific locations according to the condition of the rice noodles themselves.

[0011] Further, the step of calculating the estimated current moisture content of the rice noodles and the amount of moisture to be removed includes: The intake air temperature and the intake air relative humidity are converted into intake air absolute moisture content, and the exhaust air temperature and the exhaust air relative humidity are converted into exhaust air absolute moisture content. The exhaust water carrying capacity is calculated based on the actual exhaust air volume, the preset air density, and the difference between the intake air absolute moisture content and the exhaust air absolute moisture content. The amount of water loss is obtained by integrating and accumulating the exhaust water carrying capacity within a preset sliding window time. The water loss is then compensated for by combining the preset moisture correction coefficient with the online moisture content detection value of the rice noodles, and the current estimated moisture content of the rice noodles is calculated. The difference between the current estimated moisture content of the rice noodles and the preset target final moisture content is calculated to obtain the amount of moisture to be removed.

[0012] By employing the above technical solution, the online moisture content detection value of the rice noodles is integrally compensated using the exhaust water-carrying capacity to calculate the estimated current moisture content of the rice noodles, and the amount of water to be removed is also calculated. This method can reduce the online detection deviation caused by surface dehydration of the rice noodles, enabling the system to accurately obtain the actual dehydration state of the rice noodles.

[0013] Furthermore, the step of calculating the amount of bactericidal effect to be supplemented includes: Call the sterilization efficiency correction function generated by mapping the current estimated rice flour moisture content, the inlet air temperature, and the inlet air relative humidity; Along the cumulative residence time of the rice noodles, the product of the output of the sterilization actuator, the preset intensity conversion coefficient, and the sterilization efficiency correction function is continuously integrated to obtain the current cumulative sterilization effect. The difference between the pre-set target bactericidal effect and the current cumulative bactericidal effect is calculated to obtain the bactericidal effect to be supplemented.

[0014] By adopting the above technical solution, a sterilization efficiency correction function is introduced, which is jointly mapped from the estimated current rice flour moisture content, the inlet air temperature, and the inlet air relative humidity. This function is then used to integrate the output of the sterilization actuator to obtain the required additional sterilization effect. This method enables the control system to reflect the influence of actual temperature and humidity on the sterilization process, providing a basis for determining the priority of the linkage control.

[0015] Furthermore, the step of determining whether to enter the cooperative control zone includes: Extract the estimated current rice noodle moisture content and the amount of sterilization to be supplemented, and input them into a preset logic boundary verification program to generate a collaborative control logic state value; When the current estimated moisture content of rice noodles is between the second moisture content threshold and the first moisture content threshold, and the amount of sterilization to be supplemented is greater than the preset residual threshold of sterilization amount, a collaborative control logic state value for entering the state is generated, triggering entry into the collaborative control interval. When the collaborative control logic state value of the entry state is not generated and the current estimated moisture content of rice noodles is greater than the first moisture content threshold, the pre-drying control command is maintained.

[0016] By employing the above technical solution, the system determines whether rice noodles have entered the collaborative control range based on the first moisture content threshold, the second moisture content threshold, and the residual sterilization threshold. This determination process ensures that the system performs joint processing while the rice noodles still have a suitable moisture content.

[0017] Furthermore, the step of quantitatively calculating the risk value of the surface over-drying includes: Extract the moisture state change data per unit time, and calculate the water loss rate and the change rate of absolute moisture content in the exhaust air per unit time based on the moisture state change data. The water loss rate per unit time, the inlet air temperature, the rate of change of absolute moisture content in the exhaust air, the reciprocal of the current estimated moisture content of the rice noodles, and the cumulative residence time of the rice noodles are all substituted into a preset risk assessment model, and the risk value of the surface being too dry is output after weighted mapping calculation.

[0018] By adopting the above technical solution, the risk value of excessive surface dryness is calculated based on the water loss rate per unit time, the inlet air temperature, the rate of change of absolute moisture content in the exhaust air, the estimated current moisture content of the rice noodles, and the cumulative residence time of the rice noodles. When there is a risk of excessive surface dryness, it can provide a linkage control criterion for subsequently prioritizing increasing the proportion of circulating air or reducing the dehumidification intensity.

[0019] Furthermore, the steps of controlling the discharge volume of the dehumidification channel, the proportion of circulating air inside the drying chamber, the running speed of the conveyor belt, and the output of the sterilization actuator include the operation of executing a circulating pneumatic feedback constraint based on a sterilization priority criterion: The opening of the dehumidification valve is forced to remain unchanged or decrease, thereby limiting the amount of moisture discharged through the dehumidification channel. The opening degree of the circulating air valve is increased synchronously to improve the proportion of circulating air inside the drying chamber.

[0020] By adopting the above technical solution, after entering the coordinated control zone, the opening of the dehumidification valve is forced to remain unchanged or decrease, while the opening of the circulating air valve is simultaneously increased. This method can limit the strong dehumidification action according to the amount of sterilization effect to be supplemented, and prioritize increasing the proportion of circulating air rather than continuing forced dehumidification, maintaining the appropriate state required for the main sterilization treatment and reducing additional residence time.

[0021] Furthermore, the steps of controlling the discharge volume of the dehumidification channel, the proportion of circulating air inside the drying chamber, the running speed of the conveyor belt, and the output of the sterilization actuator include the operation of performing multi-field decoupling and dehydration sterilization speed compensation control: When it is determined that the absolute moisture content of the exhaust air is greater than the preset high humidity threshold and the risk value of the surface being too dry is greater than the preset safety risk threshold, the frequency of the circulating fan is increased, the current opening of the exhaust valve is locked, and the increase in the output of the heat source is limited. When it is determined that the amount of sterilization effect to be supplemented is greater than the preset high gap threshold and the amount of water to be removed is less than the preset small dehydration threshold, the conveyor belt running speed is reduced, the cumulative residence time of the rice noodles is extended, or the output of the sterilization actuator is increased independently. When the amount of sterilization effect to be supplemented is detected to drop to a preset zero threshold, the output of the sterilization actuator is reduced.

[0022] By adopting the above technical solution, when the risk value of the surface being too dry is high, the system locks the opening of the dehumidification valve and increases the frequency of the circulating fan to prevent the rice flour surface from hardening and insufficient internal moisture migration. When the amount of moisture to be removed is small and the amount of sterilization to be replenished is large, the system reduces the running speed of the conveyor belt or independently increases the output of the sterilization actuator to reduce the risk of increased breakage rate.

[0023] Furthermore, the steps of exiting the coordinated control zone and calculating the dehumidification energy efficiency evaluation value include: Remove the cyclic pneumatic feedback constraint based on the sterilization priority criterion, restore pneumatic regulation, and adjust the output of the sterilization actuator to zero to cut off the sterilization effect; The difference between the exhaust water carrying capacity and the exhaust water carrying capacity at the time of the previous control cycle is calculated as the dehumidification water carrying increment. The difference between the energy consumption per unit time of the production line and the energy consumption per unit time of the production line at the time of the previous control cycle is calculated as the system energy consumption increment. The ratio of the dehumidification water carrying increment to the system energy consumption increment is used as the dehumidification energy efficiency evaluation value.

[0024] By adopting the above technical solution, after the required amount of sterilization effect is reached, the constraint is removed and the system switches to dehydration control mode, and the dehumidification energy efficiency evaluation value is calculated. This method establishes a correlation between the increase in dehumidification water carryover and the increase in system energy consumption, providing a basis for subsequent dehumidification control based on the effective water carryover corresponding to the unit dehumidification energy consumption.

[0025] Furthermore, the steps for determining whether to increase or decrease the dehumidification action and resetting each actuator to the material discharge standby condition include: The dehumidification energy efficiency assessment value is compared with a preset efficiency benchmark threshold. When the dehumidification energy efficiency assessment value is greater than or equal to the efficiency benchmark threshold, the frequency of the dehumidification fan is increased or the opening of the dehumidification valve is increased. When the dehumidification energy efficiency assessment value is less than the efficiency benchmark threshold, the frequency of the dehumidification fan is reduced and the opening of the dehumidification valve is decreased. When it is determined that the amount of water to be removed is less than or equal to zero and the amount of sterilization to be replenished is less than or equal to zero, the output of the heat source is forcibly adjusted to zero, the frequency of the dehumidifying fan, the frequency of the circulating fan, the opening degree of the dehumidifying valve and the opening degree of the circulating air valve are adjusted to the preset values ​​of the material discharge standby working condition, and the running speed of the conveyor belt is adjusted to the set subsequent material discharge process speed.

[0026] By adopting the above technical solution, the opening degree of the dehumidification valve and the frequency of the dehumidification fan are controlled according to the dehumidification energy efficiency evaluation value, avoiding inefficient dehumidification when the dehumidification capacity decreases, thereby reducing exhaust heat loss and energy consumption. When all set targets are achieved, each actuator is adjusted to the material discharge standby condition to ensure the stability of continuous production.

[0027] This invention provides an energy-saving integrated production control method for drying and sterilizing rice noodles. It has the following beneficial effects: 1. This invention calculates the estimated current moisture content of rice noodles, the amount of moisture to be removed, and the amount of sterilization to be replenished by collecting production status data. It determines whether to enter the collaborative control zone by combining the first moisture content threshold and the second moisture content threshold. Based on the risk value of excessive dryness of the surface, it controls the discharge volume of the dehumidification channel, the proportion of circulating air in the drying chamber, the running speed of the conveyor belt, and the output of the sterilization actuator. This enables the control system to adjust its actions according to the state of the rice noodles to improve the stability of the continuous production process.

[0028] 2. This invention implements a circulating pneumatic feedback constraint based on the sterilization priority criterion within the collaborative control range, forcing the opening of the dehumidification valve to remain unchanged or decrease, and synchronously driving the opening of the circulating air valve to increase the proportion of circulating air inside the drying chamber. Combined with the risk value of excessive surface dryness, the frequency of the circulating fan is adjusted or the running speed of the conveyor belt is reduced, so that the main sterilization process is completed when the rice flour has a suitable moisture content, which alleviates surface hardening and maintains the continuity of internal moisture migration to the outside.

[0029] 3. This invention exits the coordinated control zone when the amount of sterilization to be replenished reaches the required level but the amount of moisture to be removed does not meet the standard. The ratio of the increase in water content during dehumidification to the increase in system energy consumption is used as the dehumidification energy efficiency evaluation value, and compared with the efficiency benchmark threshold to determine the increase or decrease of the dehumidification fan frequency and the dehumidification valve opening. This avoids continuing inefficient dehumidification during the stage when the dehumidification water content decreases, reduces heat loss caused by the exhaust of hot and humid air, and lowers system energy consumption. Attached Figure Description

[0030] Figure 1 This is a flowchart of an energy-saving integrated production control method for drying and sterilizing rice noodles according to an embodiment of the present invention; Figure 2 This is a flowchart of the spatiotemporal mapping of production status data acquisition and material transportation according to an embodiment of the present invention; Figure 3 This is a flowchart illustrating the calculation of the amount of water to be removed from rice flour and the amount of sterilization to be replenished, according to an embodiment of the present invention. Figure 4 This is a flowchart illustrating the determination of the drying and sterilization synergistic control zone according to an embodiment of the present invention. Figure 5 This is a flowchart of the surface dryness risk assessment and linkage control under the collaborative control state according to an embodiment of the present invention; Figure 6 This is a flowchart of the energy-saving dehydration control and terminal condition reset after sterilization meets the standard according to one embodiment of the present invention; Figure 7 This is a time response comparison curve of the surface moisture migration stress of rice noodles according to an embodiment of the present invention; Figure 8 This is a power spectral density envelope diagram of the instantaneous energy consumption of system dehumidification according to an embodiment of the present invention. Detailed Implementation

[0031] The technical solutions in 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.

[0032] The energy-saving integrated production control method for drying and sterilizing rice noodles provided by this invention relies on a continuous drying and sterilization production line equipped with a sensor network and corresponding actuators. This production line mainly includes a material conveying mechanism, a hot air circulation system, a dehumidification system, and sterilization actuators. The material conveying mechanism uses a continuously operating mesh belt conveyor or rod-type conveyor, running through the entire drying chamber. The hot air circulation system includes an air inlet duct, a return air duct, and airflow guide baffles distributed throughout the drying chamber. The dehumidification system is connected to the main chamber of the drying chamber and has an independent exhaust duct.

[0033] A sensor network is arranged along the material conveying direction on the production line. Temperature and relative humidity sensors are installed at the air inlet, air outlet, and exhaust duct of the hot air circulation system. Online moisture detection devices for rice noodles are installed at the drying chamber outlet and designated intermediate sections. These devices use microwave moisture meters or near-infrared moisture meters to sample and detect the moisture content of the rice noodles on the conveyor belt. An airflow detection device is installed in the exhaust duct to obtain the actual volumetric flow rate of the exhaust air. Energy consumption detection modules are configured in the power supply circuits of the main power supply and each major energy-consuming component to synchronously record the system's current instantaneous power and cumulative energy consumption.

[0034] The physical operations of the production line are completed by corresponding hardware actuators. The hot air circulation system is equipped with a circulating fan and an electric circulating air valve; the circulating fan is driven by an AC speed-regulating motor with a frequency converter. The dehumidification system is equipped with a variable frequency dehumidification fan and an electric dehumidification valve. The drying chamber is equipped with a heat source regulation device, which consists of an electric heating power controller and a steam proportional regulating valve or a gas proportional regulating valve. The sterilization actuators are distributed along the material conveying path and include hot air sterilization units, ozone generating arrays, or ultraviolet irradiation modules. The sterilization actuators have independent adjustable output interfaces, which can change the set hot air temperature, ozone generation concentration, or ultraviolet irradiation intensity by receiving external commands.

[0035] The industrial control system layer, serving as the main execution entity for production control, employs a programmable logic controller (PLC) or an industrial computer. This layer communicates with the sensor network and various actuators via fieldbus or industrial Ethernet. Internally, the industrial control system layer includes data storage units, logic operation units, and instruction output units. The data storage units record periodically sampled air thermodynamic states, equipment operating states, and material state parameters. The logic operation units perform matrix operations and state determinations on the input parameters according to preset control logic rules. The instruction output units send the calculated continuous adjustment signals or switching signals to various frequency converters, electric valves, heat source regulating devices, and sterilization actuators.

[0036] See attached document Figure 1 This invention provides an energy-saving integrated production control method for drying and sterilizing rice flour, comprising the following steps: S10. Collect production status data during the rice noodle drying and sterilization process. As the rice noodles continuously pass through the production line, the control system establishes batch spatial records based on the feeding time and conveying position, and periodically collects air thermodynamic status data, pneumatic and valve control status data, energy input and material conveying status data, as well as online moisture content and sterilization output status data.

[0037] S20. Calculate the amount of water to be removed from the rice noodles and the amount of sterilization to be replenished. The control system calculates the amount of water carried out per unit time based on the difference in absolute humidity between the inlet and outlet air. It then uses the amount of water carried out to perform an integral correction on the online detected moisture content to obtain an estimated value of the current moisture content, and subsequently calculates the amount of water to be removed. Simultaneously, it combines environmental parameters and sterilization intensity conversion factors to accumulate and calculate the obtained sterilization amount, and derives the amount of sterilization to be replenished.

[0038] S30. Determine whether the rice noodles have entered the drying and sterilization synergistic control zone. The control system performs Boolean logic verification based on the preset first moisture content threshold and second moisture content threshold, combined with the current estimated moisture content and the amount of sterilization to be supplemented, to determine whether the current batch of rice noodles is in a normal pre-drying state or has entered a synergistic control condition state that can simultaneously receive dehydration and sterilization.

[0039] S40. In the coordinated control state, the dehumidification, circulating air, conveyor speed, and sterilization output are controlled in conjunction. After determining that the system has entered the coordinated control zone, the control system quantifies the risk value of excessive surface dryness and maintains the humid and hot circulating environment and limits the rapid dehydration and hardening of the surface by limiting the opening increment of the dehumidification valve, prioritizing the increase of the circulating air ratio, adjusting the conveyor belt speed, or increasing the sterilization power output.

[0040] S50: After sterilization meets the standard, switch to energy-saving dehydration control and complete the endpoint control. When the amount of sterilization to be supplemented meets the requirements but the moisture content does not meet the standard, the control system exits the collaborative state and determines the increase or decrease of subsequent dehumidification actions based on the effective moisture removal efficiency index corresponding to the unit energy consumption, until both the amount of moisture to be removed and the amount of sterilization to be supplemented reach the target set range, and then adjusts and resets each actuator to the discharge standby condition.

[0041] The specific implementation details of each of the above steps are explained in detail below.

[0042] See attached document Figure 2 In order to achieve precise intervention of control commands on the material body during continuous operation and avoid control action lag or misalignment, industrial control systems need to establish a synchronous mapping relationship between the physical location of the material and multi-dimensional operating parameters, and process discrete sensor data in the same time and space dimension.

[0043] S101. Establish a spatiotemporal mapping record for rice noodle material conveying. The data acquisition unit inside the industrial control system periodically samples the system according to discrete time steps. Let the current sampling time be... .

[0044] When a new batch or section of rice noodles enters the feed end of the continuous drying and sterilization production line, the data storage unit records the feeding time. The logic unit of the industrial control system operates based on real-time feedback of the conveyor belt speed. The physical location of rice noodles in the drying chamber is calculated by integrating the current conveyor belt speed. ...

[0045] From a physical perspective, since continuous production lines typically have a length-to-diameter ratio of over 10 meters, the thermodynamic environment of materials differs at different spatial nodes. Establishing spatiotemporal coordinates is a prerequisite for achieving subsequent independent compensation in each segment. Physical location The calculation formula is as follows: ; in, For physical location; This is the definite integral operator; This refers to the feeding time; This is the current sampling time; The speed of the conveyor belt; For integration time; This is the symbol for an integral infinitesimal element.

[0046] The logic unit synchronously calculates the cumulative residence time of this batch of rice noodles in the drying chamber. Cumulative stay time The calculation formula is as follows: ; in, This refers to the total time spent in the place. This is the current sampling time; This is the feeding time.

[0047] By combining data from the front-end feeding process or weighing sensors, the industrial control system binds the spatial coordinates and time axis of the rice noodles in a specific area, forming a complete material tracking record.

[0048] S102. Dynamically acquire multi-dimensional production status data. Within the same control cycle of material tracking, the data acquisition unit synchronously reads various operating parameters at the current sampling moment through the sensor network and actuator feedback interface configured inside the production line. The parameters read by the data acquisition unit are divided into four physical sets.

[0049] The air thermodynamic state dataset includes inlet air temperature, return air temperature, exhaust air temperature, inlet air relative humidity, return air relative humidity, and exhaust air relative humidity.

[0050] The pneumatic and valve control status dataset includes the frequency of the circulating fan, the frequency of the exhaust fan, the actual exhaust air volume, the opening degree of the exhaust valve, and the opening degree of the circulating air valve.

[0051] The energy input and material conveying status dataset includes heat source output, production line energy consumption per unit time, and conveyor belt speed. Heat source output is reflected in the duty cycle of electric heating control, the opening degree of steam regulating valve, or the opening degree of the proportional output valve of gas burner, depending on the specific heating source.

[0052] The online moisture content and sterilization output status dataset includes the online moisture content detection value of rice noodles and the output of the sterilization actuator. The output of the sterilization actuator is reflected in the set hot air sterilization temperature, ozone generator array concentration, or ultraviolet module irradiation intensity, depending on the configured unit type.

[0053] See attached document Figure 3 After acquiring real-time spatial mapping records and multi-dimensional sensor data, the logic operation unit needs to convert the air thermodynamic state parameters characterizing the external environment into internal process state parameters reflecting the dehydration progress and sterilization effect of the rice flour itself. This provides accurate numerical basis for subsequent state determination and linkage control of the actuators. The sensor hardware interface configuration, analog-to-digital conversion, and data communication involved are all conventional technologies in this field and will not be elaborated further.

[0054] S201. Calculate the amount of moisture carried out by the exhaust air and the dynamically corrected moisture content estimate. The logic unit substitutes the inlet air temperature and relative humidity into the wet air state equation to obtain the absolute moisture content of the inlet air. By combining the exhaust air temperature and relative humidity, the absolute moisture content of the exhaust air is calculated simultaneously. .

[0055] The logic operation unit is based on the actual exhaust air volume. The difference in absolute moisture content before and after dehumidification is used to calculate the amount of water carried out by the exhaust system per unit time, i.e., the water-carrying capacity of the exhaust system. Exhaust water carrying capacity The calculation formula is as follows: ; in, For exhaust water carrying capacity; This refers to the actual exhaust air volume. air density; This refers to the absolute moisture content of the exhaust air. This refers to the absolute moisture content of the incoming air.

[0056] Online moisture content test value for rice noodles It mainly reflects the surface moisture of the material. During continuous hot air contact, it is easily affected by the hardening of the surface crust, which can cause local measurement deviations. That is, the apparent dryness phenomenon is caused by the rapid evaporation of surface moisture and the obstruction of internal moisture diffusion.

[0057] The logic unit utilizes the exhaust and water carrying capacity. The cumulative moisture loss over the sliding window period is used to measure the online moisture content of rice noodles. Dynamic compensation is performed to calculate the estimated current moisture content of the rice noodles. Current estimated moisture content of rice noodles The calculation formula is as follows: ; in, This is an estimated value for the current moisture content of the rice noodles; This refers to the online moisture content measurement value of rice noodles. Moisture correction factor; This is the definite integral operator; This is the current sampling time; The time interval for sliding window integration; For exhaust water carrying capacity; The amount of powder coating per unit length; The speed of the conveyor belt; For integration time; This is the symbol for an integral infinitesimal element.

[0058] The value of the moisture correction factor is usually obtained by fitting the historical deviation between the laboratory standard oven constant weight method and the online instrument measurement value, and the value range is generally between 0.85 and 1.15.

[0059] Get the current estimated moisture content of rice noodles Then, the logic unit reads the preset target final moisture content. Calculate the amount of water to be removed. The amount of water to be removed The calculation formula is as follows: ; in, The amount of water to be removed; This is an estimated value for the current moisture content of the rice noodles; The target final moisture content.

[0060] S202. Calculate the sterilization effect under the influence of time-varying environment. The sterilization effect of rice noodles inside the drying chamber is not solely determined by the output parameters of the external sterilization device. The moisture content of the rice noodles themselves, as well as the temperature and humidity of the environment, will change the heat transfer efficiency and sterilization penetration depth. From a physical perspective, in environments with higher moisture and humidity, microbial proteins are more prone to denaturation and aggregation, meaning that moist heat sterilization is more effective than simple dry heat sterilization.

[0061] Therefore, the logic unit has a built-in estimate of the current rice noodle moisture content. Inlet air temperature relative humidity of incoming air Sterilization efficiency correction function generated by co-mapping .

[0062] The logic unit calculates the cumulative residence time of the rice noodles in the drying chamber. Output of the sterilization actuator Perform continuous integration to obtain the current cumulative bactericidal effect. Current cumulative bactericidal effect The calculation formula is as follows: ; in, This represents the current cumulative bactericidal effect. This is the definite integral operator; This refers to the total time spent in the place. This is the strength conversion factor; Output of the sterilization actuator; This is a function to correct for sterilization efficiency. This is an estimated value for the current moisture content of the rice noodles; Intake air temperature; The relative humidity of the incoming air; For integration time; This is the symbol for an integral infinitesimal element.

[0063] The intensity conversion factor can be obtained by back-calculating the lethality D-value and Z-value of specific target microorganisms, such as Escherichia coli or Bacillus subtilis. When the sterilization actuator is configured as a hot air sterilization unit, this factor is the heat conduction equivalent factor; when configured as an ozone generating array, this factor is the ozone concentration decay contact factor.

[0064] After obtaining the current cumulative bactericidal effect Then, the logic unit performs the sterilization based on the target sterilization dosage set in the production process. Calculate the amount of bactericidal effect to be supplemented. The amount of bactericidal agent needs to be replenished. The calculation formula is as follows: ; in, The amount of bactericidal effect needs to be replenished; The target bactericidal dose; This represents the current cumulative bactericidal effect.

[0065] See attached document Figure 4 After calculating the estimated current moisture content of the rice noodles and the amount of sterilization to be replenished, the logic unit needs to identify the most suitable physical window for simultaneously performing dehydration and sterilization operations based on the current dehydration progress and sterilization gap of the rice noodles, so as to avoid surface heat damage or energy waste caused by applying strong sterilization action when the material is too wet or too dry.

[0066] S301. Establish a moisture content boundary for drying and sterilization. Because rice noodles have weak structural load-bearing capacity when the moisture content is too high, and the surface water layer transfer effect is reduced when the moisture content is too low, resulting in a decrease in the heat penetration of sterilization, the industrial control system needs to define a specific process moisture range.

[0067] The data storage unit is preloaded with a first moisture content threshold. With the second moisture content threshold First moisture content threshold The upper limit of this physical range, the second moisture content threshold. This is the lower limit of the physical interval.

[0068] The specific values ​​of these two thresholds are generated by the industrial control system through reverse constraint fitting of feedback data on material breakage rate and unit energy consumption characteristics from historical production batches. These values ​​characterize the optimal range that balances the material's heat-bearing capacity and the continuity of internal moisture conduction. As a specific engineering implementation, the first moisture content threshold can be set to 35%, and the second moisture content threshold can be set to 18%.

[0069] S302. Execute the multi-state logic transition determination for the drying and sterilization process. Within each discrete control cycle, the logic operation unit extracts the estimated current moisture content of the rice noodles. With the amount of bactericidal effect to be replenished The values ​​are then input into the logic boundary check and Boolean operation program to generate the collaborative control logic state values. Cooperative control logic state values The determination formula is as follows: ; in, For collaborative control logic state values; This is the second moisture content threshold; This is an estimated value for the current moisture content of the rice noodles; The first moisture content threshold; The amount of bactericidal effect needs to be replenished; This represents the residual threshold for bactericidal action.

[0070] The purpose of the sterilization effect margin threshold is to set a buffer zone, typically set at 5% to 10% of the target sterilization effect. The logic unit determines whether the sterilization effect to be supplemented is greater than the sterilization effect margin threshold, thus preventing the system from forcibly maintaining a high-intensity collaborative operation state when the sterilization target is about to be completed.

[0071] When the calculated collaborative control logic state value is 0 and the current estimated moisture content of rice noodles is greater than the first moisture content threshold, the logic operation unit determines that the current material moisture content is too high and does not yet meet the conditions for withstanding a strong sterilization process. The instruction output unit continues to output the normal heating and pre-drying control instructions.

[0072] When the calculated collaborative control logic state value is 1, the logic operation unit determines that the rice noodles in a specific section of the current production line have entered a suitable physical window for joint processing. The instruction output unit then formally switches the execution state of the control flow into the drying and sterilization collaborative control interval, and provides trigger signals for subsequent multi-variable closed-loop linkage constraints. The basic data processing procedures involved, such as historical data extraction and multiple linear regression, are standard techniques in the field and will not be elaborated further.

[0073] See attached document Figure 5 When the control process switches to a combined drying and sterilization control state, solely pursuing the dehydration rate can easily lead to a crusting phenomenon where the surface moisture of the rice noodles evaporates rapidly while the internal moisture cannot migrate in time. Surface hardening not only hinders the subsequent dehydration process but also forms a dense heat insulation layer, reducing the penetration depth of heat and other sterilization media into the rice noodles.

[0074] Therefore, before issuing specific linkage adjustment instructions to the actuators, the logic operation unit needs to perform real-time quantitative calculations on the degree of imbalance between the internal and surface moisture migration of the material.

[0075] S401, Quantify the risk assessment value of excessive dryness on the surface of materials. The logic operation unit extracts the moisture state change data per unit time and calculates the water loss rate per unit time. Change rate of absolute moisture content in exhaust air .

[0076] Water loss rate per unit time The macroscopic rate at which rice noodles lose moisture is calculated using the following formula: ; in, Water loss rate per unit time; This is an estimated value for the current moisture content of the rice noodles; The derivative operator represents the rate of change of a variable over time.

[0077] absolute moisture content change rate of exhaust air The transient change trend of the dehumidification efficiency of the drying chamber is characterized by the following formula: ; in, The absolute moisture content change rate of the exhaust air; This refers to the absolute moisture content of the exhaust air. The derivative operator represents the rate of change of a variable over time.

[0078] After obtaining these rate of change parameters, the logic unit will calculate the water loss rate per unit time. Inlet air temperature , Absolute moisture content change rate of exhaust air Current estimated moisture content of rice noodles and cumulative stay time The samples are jointly substituted into the risk assessment model, and after weighted mapping, the surface over-drying risk value is output. Risk value of excessively dry surface The calculation formula is as follows: ; in, This represents the risk value for excessively dry surface layer. , , , , All are weighting coefficients; Water loss rate per unit time; Intake air temperature; The absolute moisture content change rate of the exhaust air; This is an estimated value for the current moisture content of the rice noodles; This refers to the total time spent in the place.

[0079] These weighting coefficients can be obtained by extracting features and weighting from defective product samples that have experienced surface crusting and breakage in historical production through principal component analysis or multiple linear regression algorithms. This operational logic establishes a quantitative characterization of the imbalance between internal and external moisture migration from a physical mechanism perspective: when the rice noodles lose water too quickly, the inlet air temperature is too high, the increase in moisture content in the exhaust air of the drying chamber is hindered, the moisture content is low, and the residence time in the drying chamber is prolonged, the calculated risk value of excessive surface dryness will increase significantly. This indicates that the rate of moisture loss from the surface of the rice noodles has exceeded the rate of internal moisture diffusion to the surface, and the surface is in a critical state of hardening and crusting.

[0080] S402. Execute cyclic pneumatic feedback constraints based on the sterilization priority criterion. Under cooperative control, since the determination condition for entering the cooperative control interval includes that the amount of sterilization effect to be supplemented is greater than the residual threshold of the sterilization effect, it indicates that the sterilization process of the rice noodles in the current section has not yet met the standard.

[0081] If the command output unit continues to output control commands that aim for the maximum dehumidification rate during this stage, it will cause the humidity content of the air inside the drying chamber to decrease. The dry air will not only accelerate the loss of moisture from the surface of the rice noodles, inducing surface hardening, but will also carry away a large amount of latent heat of vaporization, destroying the humid and hot environment that is conducive to the penetration and conduction of heat and sterilization media into the material.

[0082] To ensure sterilization quality, the logic unit establishes and executes a pneumatic constraint rule prioritizing sterilization. The instruction output unit at the industrial control system layer issues intervention commands to the dehumidification system and hot air circulation system, actively limiting the emission volume of the dehumidification channel and forcibly increasing the circulation ratio of the internal circulating air. The control logic expression for this constraint rule is as follows: These weighting coefficients can be obtained by extracting features and weighting from defective product samples that have experienced surface crusting and breakage in historical production through principal component analysis or multiple linear regression algorithms. This operational logic establishes a quantitative characterization of the imbalance between internal and external moisture migration from a physical mechanism perspective: when the rice noodles lose water too quickly, the inlet air temperature is too high, the increase in moisture content in the exhaust air of the drying chamber is hindered, the moisture content is low, and the residence time in the drying chamber is prolonged, the calculated risk value of excessive surface dryness will increase significantly. This indicates that the rate of moisture loss from the surface of the rice noodles has exceeded the rate of internal moisture diffusion to the surface, and the surface is in a critical state of hardening and crusting.

[0083] S402. Execute cyclic pneumatic feedback constraints based on the sterilization priority criterion. Under cooperative control, since the determination condition for entering the cooperative control interval includes that the amount of sterilization effect to be supplemented is greater than the residual threshold of the sterilization effect, it indicates that the sterilization process of the rice noodles in the current section has not yet met the standard.

[0084] If the command output unit continues to output control commands that aim for the maximum dehumidification rate during this stage, it will cause the humidity content of the air inside the drying chamber to decrease. The dry air will not only accelerate the loss of moisture from the surface of the rice noodles, inducing surface hardening, but will also carry away a large amount of latent heat of vaporization, destroying the humid and hot environment that is conducive to the penetration and conduction of heat and sterilization media into the material.

[0085] To ensure sterilization quality, the logic unit establishes and executes a pneumatic constraint rule prioritizing sterilization. The instruction output unit at the industrial control system layer issues intervention commands to the dehumidification system and hot air circulation system, actively limiting the emission volume of the dehumidification channel and forcibly increasing the circulation ratio of the internal circulating air. The control logic expression for this constraint rule is as follows: ; ; in, This represents the change in the opening degree of the exhaust valve during the current control cycle. This represents the change in the opening degree of the circulating air valve during the current control cycle.

[0086] The command output unit sends adjustment signals to the positioners of the electric dehumidification valve and the electric circulating air valve through the fieldbus or analog output module, forcing the opening of the dehumidification valve to remain unchanged or decrease appropriately, and synchronously driving the opening of the circulating air valve to increase.

[0087] By rigidly constraining the changes in valve opening, the industrial control system suppresses the outward discharge of internal gaseous moisture while increasing the air circulation speed inside the drying chamber, maintaining a high relative humidity and enthalpy value, thereby ensuring that the output of the sterilization actuator can continuously and stably act on the rice noodle body.

[0088] S403. Execute multi-field decoupling and dehydration / sterilization rate compensation control. Under coordinated control, the interaction between the humid and hot environment inside the drying chamber and the moisture migration of the material often results in a rate mismatch between the dehydration and sterilization processes. The logic unit implements targeted compensation rules based on real-time status parameters and multi-dimensional evaluation results.

[0089] When the logic unit determines that the absolute humidity of the exhaust air is greater than the preset high humidity threshold and the risk value of excessive dryness on the surface is greater than the preset safety risk threshold, it indicates that the current dry indoor air has a high moisture holding capacity, but the speed at which the internal moisture of the rice noodles migrates outward is seriously lagging behind the speed at which the surface moisture evaporates.

[0090] The high humidity threshold is determined by adding a fixed humidity increment to the local seasonal atmospheric background humidity, while the safety risk threshold is calibrated based on the product's permissible surface microcrack limit test data. To suppress the risk of excessive surface dryness, the instruction output unit executes the following action logic: ; ; ; in, This represents the change in the opening degree of the exhaust valve during the current control cycle. This represents the change in the frequency of the circulating fan during the current control cycle. This refers to the output of the heat source. The derivative operator represents the rate of change of a variable over time.

[0091] In practical implementation, the command output unit sends an up-frequency signal to the inverter of the circulating fan to enhance the airflow disturbance inside the drying chamber, simultaneously locks the current opening of the electric dehumidification valve, and sends a command to the heat source regulating device to limit further increases in output power. By increasing the circulating airflow without increasing the direct dehumidification volume and heat source input, the system effectively weakens the rapid surface dehydration effect and alleviates the hardening of the material surface.

[0092] When the logic unit determines that the amount of sterilization to be compensated is greater than the preset high-gap threshold, and the amount of moisture to be removed is less than the preset micro-dehydration threshold, it indicates that the dehydration process of the rice noodles is significantly ahead of schedule and close to the final set range, while the sterilization process is significantly behind schedule. The high-gap threshold is usually set to be more than 30% of the target sterilization amount, and the micro-dehydration threshold is set to be within the positive bias range of the final product's moisture tolerance bandwidth. The instruction output unit immediately executes the compensation logic for the delayed dehydration: ; or: ; in, This represents the change in the conveyor belt speed during the current control cycle. This refers to the change in the output of the sterilization actuator during the current control cycle.

[0093] The instruction output unit sends a speed reduction instruction to the drive inverter of the material conveying mechanism to forcibly reduce the running speed of the conveyor belt, thereby extending the cumulative residence time of rice noodles in the drying chamber; or it sends an instruction to the control interface of the hot air sterilization unit, ozone generating array or ultraviolet irradiation module to increase the output intensity, so as to quickly make up for the sterilization effect gap without aggravating the dehydration of the material.

[0094] Furthermore, when the logic unit detects that the amount of sterilization effect to be replenished is continuously decreasing and approaching zero, the instruction output unit executes the following action logic: ; in, This represents the change in the output of the sterilization actuator during the current control cycle. The command output unit smoothly decays the set parameters of the sterilization actuator to prevent excessive energy consumption and physical structural damage to the rice flour material caused by over-sterilization, thus achieving decoupling and smooth transition of multiple physical field effects.

[0095] See attached document Figure 6 After the coordinated control phase of drying and sterilization, as the material continues to operate in the drying chamber, the heat absorbed by the rice flour in specific sections and the sterilization medium gradually accumulate. When the preset sterilization target is achieved but the moisture removal process has not yet ended, the industrial control system must promptly exit the coordinated state of multiple variables constraining each other, remove the pneumatic dehumidification restrictions imposed to ensure sterilization, and reduce the control dimension to a single physical dehydration mode to avoid unnecessary energy consumption.

[0096] S501, Perform dimensionality reduction determination and smooth switching of the execution control state. Within each control cycle, the logic operation unit continuously extracts the amount of sterilization effect to be supplemented and the amount of moisture to be removed at the current sampling time. The logic operation unit determines that the following conditions are met: ; ; in, The amount of bactericidal effect needs to be replenished; The amount of water to be removed.

[0097] This indicates that the rice noodles at the current physical location have completely passed the sterilization threshold, but their internal moisture content still does not meet the standard set by the process. At this point, the command output unit immediately removes the cyclic pneumatic feedback constraint logic based on the sterilization priority criterion, and no longer forces the change in the opening of the dehumidification valve during the current control cycle. The limitations are removed, thereby restoring the independent regulation capabilities of the dehumidification system and the hot air circulation system.

[0098] Simultaneously, the command output unit sends a termination signal to the sterilization devices arranged along the line, adjusting the output of the sterilization actuator corresponding to that section to zero, and physically cutting off the additional heat source supply of the hot air sterilization unit, stopping the ozone injection of the ozone generating array, or turning off the ultraviolet irradiation module.

[0099] By removing the hard boundaries of these control parameters and zeroing the output of the sterilization actuator, the control process smoothly exits the collaborative control range and completes the switch to the conventional energy-saving dehydration mode.

[0100] S502. Execute dynamic dehumidification control driven by performance performance indicators. After smoothly switching to a single physical dehydration mode, the main objective of the logic unit is to control external energy consumption while completing the removal of remaining moisture. Moisture evaporation in the later stages of dehydration is mainly constrained by the internal diffusion resistance of the material; simply relying on enhanced external dehumidification can easily lead to heat loss.

[0101] Therefore, the logic unit records the parameter changes before and after the dehumidification adjustment, which differ by one control cycle, and calculates the water-carrying capacity of the exhaust fan. Exhaust water carrying capacity compared to the previous control cycle The difference is used as the increase in water content in the dehumidification belt; the energy consumption per unit time of the production line is calculated simultaneously. Energy consumption per unit time of the production line at the time of the previous control cycle The difference is used as the system energy consumption increment.

[0102] The logic unit uses these differences to construct a dehumidification energy efficiency assessment value. Dehumidification energy efficiency assessment value The calculation formula is as follows: ; in, This is the dehumidification energy efficiency assessment value; For exhaust water carrying capacity; The exhaust water carrying capacity at the time of the previous control cycle; Energy consumption per unit time of the production line; This represents the energy consumption per unit time of the production line at the time of the previous control cycle. To control the periodic time interval.

[0103] Obtain dehumidification energy efficiency assessment value Then, the logic unit compares it with a pre-set performance benchmark threshold. The specific value of the performance benchmark threshold is calculated by the input terminal of the production management system based on the local industrial electricity price and the economic loss caused by the need for secondary drying due to substandard product moisture content, thus balancing the costs.

[0104] When the logic unit determines that the following conditions are met: ; in, This is the dehumidification energy efficiency assessment value; This is the performance benchmark threshold.

[0105] This indicates that the actual moisture removal gain from the current dehumidification system adjustment can cover the energy consumption cost of the fan's accelerated operation and heat loss. At this point, the command output unit continues to send an upsampling signal to the inverter of the variable frequency dehumidification fan, outputting the following action logic: ; in, This represents the change in the frequency of the dehumidifying fan during the current control cycle. Alternatively, it can send an opening increase signal to the positioner of the electric dehumidifying valve to accelerate the evaporation and removal of residual moisture from the rice noodles.

[0106] When the logic unit determines that the following conditions are met: ; in, This is the dehumidification energy efficiency assessment value; This is the performance benchmark threshold.

[0107] This indicates that the amount of moisture removed by further increasing the dehumidification intensity has diminished, and electrical and thermal energy is being consumed in the exhaust of hot, dry air, meaning that the sensible heat loss far outweighs the latent heat gain. The instruction output unit then executes the system heat loss truncation and convergence operation, outputting the following action logic: ; ; in, This represents the change in the frequency of the exhaust fan during the current control cycle. This represents the change in the opening degree of the exhaust valve during the current control cycle.

[0108] By actively reducing the operating frequency of the dehumidification fan and gradually closing the electric dehumidification valve, the industrial control system cuts off the excessive leakage of heat enthalpy from the drying chamber to the external environment, prompting the production line to rely on the residual heat retained inside and natural circulation to slowly balance the moisture content of the rice noodles, thereby achieving energy-saving convergence in the deep dehydration stage.

[0109] S503, Execute the global closed-loop control of the production line and reset the terminal operating conditions. During the dynamic dehumidification control process, the logic unit continuously evaluates the convergence status of the dual indicators of rice noodle dehydration and sterilization. When the logic unit determines that the following conditions are met: ; ; in, The amount of water to be removed; The amount of bactericidal effect needs to be replenished.

[0110] This indicates that the batch of rice noodles at the current associated spatial location has fully met the set dual objectives of drying and sterilization processes, and the control process has entered the final discharge control stage. At this time, the instruction output unit immediately issues an instruction to forcibly adjust the heat source output to zero.

[0111] In terms of specific actuator actions, the command output unit cuts off the solid-state relay control signal of the electric heating tube, completely shuts off the proportional regulating valve of the steam heating system, or stops the fuel supply of the gas burner, thereby physically cutting off the heat energy input to the drying chamber and preventing the rice noodles from charring or deteriorating in structure and quality due to excessive heating before discharge.

[0112] To facilitate the slow tempering process after discharge and promote the natural balance of moisture inside and outside the rice noodles, the command output unit synchronously outputs smooth adjustment commands for the pneumatic components. The command output unit sends frequency reduction commands to the exhaust fan and the circulating fan, and smoothly adjusts the opening of the exhaust valve and the circulating air valve to the preset values ​​for the slow tempering standby condition after discharge, so as to maintain a suitable and mild environment at the end of the drying chamber.

[0113] In addition, the command output unit outputs speed adjustment commands to the conveyor belt drive frequency converter according to the material flow rhythm requirements of the downstream slow conveyor belt or packaging line, so as to adjust the running speed of the conveyor belt to the set subsequent discharge process speed.

[0114] As the batch of rice noodles gradually leaves the continuous drying and sterilization production line, the data storage unit automatically clears the associated material conveying spatiotemporal mapping records and historical status parameter caches for that batch, completing the global closed loop of the control logic for a specific section of the production line. When a new batch or section of rice noodles enters the feeding end, the data acquisition unit re-triggers the recording of the feeding time and cyclically executes the data acquisition and multi-variable collaborative control process. The underlying speed regulation programs of the frequency converters and PID controllers involved are standard technologies in the field and will not be elaborated further.

[0115] Specific application examples: To better understand the technical solution of this invention, the invention will be further described in detail below with reference to specific application scenarios and accompanying drawings. This specific application embodiment is built on a continuous drying and sterilization production line system for straight rice noodles. The system operates in a production environment with an aspect ratio of 12 meters and is responsible for acquiring multi-physics environment data and executing multi-field decoupling and feedback control closed loop.

[0116] During the environmental data acquisition phase, the moisture prediction unit extracts data from multiple sensor sources to calculate estimated moisture content. The parameters are set as follows: Set the control cycle. The sliding window integration time interval is 10 seconds. The sampling time is 60 seconds. The conveyor belt speed fed back by the sensor The speed is 0.015 m / s, and the mass of powder coating per unit length is... The online moisture content of rice noodles is 2.0 kg / m³. It is 0.225. During the sliding window integration time interval... Internally, acquire the ability to carry water through exhaust ventilation. The average value is 0.012 kg / s, and the moisture correction factor is... The value is 1.05. The moisture prediction unit substitutes the values ​​into the formula to calculate the estimated moisture content. : ; The water carrying capacity of the exhaust system is obtained based on discretization calculation. The integral compensation is 0.0168. Substitute the value into the calculation: ; The results show that the estimated moisture content obtained by the system is... The value is 0.2418. This is the preset first moisture content threshold. The second moisture content threshold is 0.35. The value is 0.18. This is based on the calculated estimated moisture content. Falling at the second moisture content threshold To the first moisture content threshold If the conditions are met, the moisture prediction unit determines that the current material has entered the surface hardening sensitive period, and the system is activated to enter the collaborative control zone.

[0117] When the system enters the coordinated control zone, the system re-executes the state assessment procedure. The parameters are set as follows: Water loss rate per unit time within the current operating cycle. The value is 0.004, indicating the ambient intake air temperature. The absolute moisture content change rate of the exhaust air is 85. The cumulative stay time is 0.00015. The value is 400. The weighting coefficients are set as follows: First weighting coefficient... The second weighting coefficient is 200. The third weighting coefficient is 0.01. The weighting factor is 50, the fourth weighting factor. The fifth weighting coefficient is 0.05. The value is 0.002. The logic unit substitutes the values ​​into the formula to calculate the risk value of surface over-drying. : ; Substitute the values ​​into the calculation: ; The results show that the system obtains the risk value of excessive surface dryness. The value is 2.6485. The preset safety risk threshold is 2.5. This is due to the calculated risk value of an excessively dry surface layer. If the risk exceeds the safety risk threshold and meets the judgment conditions, the logic operation unit determines that there is a risk of surface crusting and microcracks. The system activates the feedback constraint module based on sterilization priority, executes the locking of the dehumidification valve and increases the circulation air operation.

[0118] In the deep dehydration stage after sterilization meets the standards, the energy efficiency assessment unit combines the water increase in the dehumidification belt. With energy consumption increment Calculate the dehumidification energy efficiency assessment value The parameters are set as follows: Obtain the value from the previous control cycle. Until this control cycle Increased water volume in the internal dehumidification belt The value is 0.004 kg / s, obtained within the same control cycle. Energy consumption increment within The energy efficiency rating is 3.2kW. The energy efficiency assessment unit is substituted into the formula to calculate the dehumidification energy efficiency assessment value. : ; Substitute the values ​​into the calculation: ; The results show that the system obtains the dehumidification energy efficiency evaluation value. The value is 0.00125 kg / kJ. This is the preset performance benchmark threshold. The value is 0.002 kg / kJ. This is based on the calculated dehumidification energy efficiency assessment value. Less than the performance benchmark threshold If the judgment conditions are met, the energy efficiency assessment unit confirms that the dehumidification energy consumption is greater than the water-carrying benefit, and the system generates and outputs a dehumidification fan frequency reduction command to reduce heat loss.

[0119] To verify the accuracy and stability of the collaborative control strategy, which incorporates multi-field decoupling and energy efficiency control mechanisms, during system operation, the system compared and output performance data of multiple control mechanisms under the same experimental environment of continuous production of 10 tons of rice noodles. The data showed that the conventional independent control group had a endpoint moisture content range of ±1.8%, a surface microcrack and breakage rate of 4.5%, an E. coli kill rate of 96.2%, and some batches that did not meet the standards, with a comprehensive energy consumption of 315 kWh / t. In contrast, the system of this invention had an endpoint moisture content range of ±0.4%, a surface microcrack and breakage rate of 0.8%, an E. coli kill rate greater than 99.9% achieving full compliance, and a comprehensive energy consumption of 268 kWh / t.

[0120] See attached document Figure 7 , Figure 7The horizontal axis represents system runtime, and the vertical axis represents the surface over-drying risk stress index. In the figure, the conventional independent control system, due to the delayed characteristics of the hot air and dehumidification systems, exhibits a low-frequency overshoot and wave-like oscillation in its surface over-drying risk stress index distribution, causing it to repeatedly exceed the 2.5 safety threshold for surface crusting and microcracks. In contrast, the system of this invention, employing a multi-field decoupling and feedback constraint mechanism, exhibits a smooth surface over-drying risk stress index distribution that slowly converges with the dehydration process, consistently remaining below the safety threshold for surface crusting and microcracks. This result verifies the invention's ability to prevent surface crusting and breakage, and to improve surface quality.

[0121] Based on the verification of the surface quality mechanism, in order to further verify the energy-saving effectiveness of the present invention in the deep dehydration process, the instantaneous energy consumption power spectral density of different control algorithms under dehumidification and energy saving was compared.

[0122] See attached document Figure 8 , Figure 8 The horizontal axis represents the operating control frequency, and the vertical axis represents the power spectral density. The conventional independent control system in the figure, lacking an energy efficiency control mechanism, exhibits a trend of a bulge in the ineffective action loss zone at mid-to-high frequencies, with high-frequency regulation leading to heat loss. The system of this invention, due to the introduction of an energy efficiency evaluation unit, shows a power spectral density distribution where the energy representing passive losses at mid-to-high frequencies is suppressed and drops to the noise floor level. The system's energy output is concentrated in the steady-state energy-saving zone approaching 0Hz. This result verifies the invention's ability to eliminate ineffective actions and achieve low-consumption operation during the deep dehydration stage.

Claims

1. An energy-saving integrated production control method for drying and sterilizing rice noodles, characterized in that, Includes the following steps: Collect production status data during the rice noodle drying and sterilization process; Based on the production status data, the estimated current moisture content of the rice noodles, the amount of moisture to be removed, and the amount of sterilization to be replenished are calculated. Based on the preset first moisture content threshold and the preset second moisture content threshold, combined with the current estimated moisture content of rice noodles and the amount of sterilization to be supplemented, it is determined whether to enter the collaborative control range; Once the system determines that the system has entered the collaborative control zone, the risk value of excessive surface dryness is quantitatively calculated, and based on the risk value of excessive surface dryness, the system controls the discharge volume of the dehumidification channel, the proportion of circulating air inside the drying chamber, the speed of the conveyor belt, and the output of the sterilization actuator. When the amount of sterilization to be replenished reaches the preset amount requirement, but the amount of moisture to be removed does not reach the preset moisture standard, the coordinated control zone is exited, the dehumidification energy efficiency evaluation value is calculated, and the dehumidification action is increased or decreased until both the amount of moisture to be removed and the amount of sterilization to be replenished reach the preset target range, and then each actuator is reset to the material discharge standby condition.

2. The energy-saving integrated production control method for drying and sterilizing rice noodles according to claim 1, characterized in that, The steps for collecting production status data during the rice noodle drying and sterilization process include: The production status data is read synchronously, including air thermodynamic status data, pneumatic and valve control status data, energy input and material conveying status data, and online moisture content and sterilization output status data. The air thermodynamic state data includes inlet air temperature, return air temperature, exhaust air temperature, inlet air relative humidity, return air relative humidity, and exhaust air relative humidity. The pneumatic and valve control status data includes the frequency of the circulating fan, the frequency of the exhaust fan, the actual exhaust air volume, the opening degree of the exhaust valve, and the opening degree of the circulating air valve. The energy input and material conveying status data include heat source output, energy consumption per unit time of the production line, and the speed of the conveyor belt. The online moisture content and sterilization output status data include the online moisture content detection value of rice noodles and the output of the sterilization actuator. The physical position of the rice noodles is obtained by integrating the conveyor belt speed at the feeding time and the current sampling time, and the cumulative residence time of the rice noodles is calculated.

3. The energy-saving integrated production control method for drying and sterilizing rice noodles according to claim 2, characterized in that, The steps for calculating the estimated current moisture content of the rice noodles and the amount of moisture to be removed include: The intake air temperature and the intake air relative humidity are converted into intake air absolute moisture content, and the exhaust air temperature and the exhaust air relative humidity are converted into exhaust air absolute moisture content. The exhaust water carrying capacity is calculated based on the actual exhaust air volume, the preset air density, and the difference between the intake air absolute moisture content and the exhaust air absolute moisture content. The amount of water loss is obtained by integrating and accumulating the exhaust water carrying capacity within a preset sliding window time. The water loss is then compensated for by combining the preset moisture correction coefficient with the online moisture content detection value of the rice noodles, and the current estimated moisture content of the rice noodles is calculated. The difference between the current estimated moisture content of the rice noodles and the preset target final moisture content is calculated to obtain the amount of moisture to be removed.

4. The energy-saving integrated production control method for drying and sterilizing rice noodles according to claim 3, characterized in that, The steps for calculating the amount of bactericidal action to be supplemented include: Call the sterilization efficiency correction function generated by mapping the current estimated rice flour moisture content, the inlet air temperature, and the inlet air relative humidity; Along the cumulative residence time of the rice noodles, the product of the output of the sterilization actuator, the preset intensity conversion coefficient, and the sterilization efficiency correction function is continuously integrated to obtain the current cumulative sterilization effect. The difference between the pre-set target bactericidal effect and the current cumulative bactericidal effect is calculated to obtain the bactericidal effect to be supplemented.

5. The energy-saving integrated production control method for drying and sterilizing rice flour according to claim 1, characterized in that, The steps for determining whether to enter the cooperative control zone include: Extract the estimated current rice noodle moisture content and the amount of sterilization to be supplemented, and input them into a preset logic boundary verification program to generate a collaborative control logic state value; When the current estimated moisture content of rice noodles is between the second moisture content threshold and the first moisture content threshold, and the amount of sterilization to be supplemented is greater than the preset residual threshold of sterilization amount, a collaborative control logic state value for entering the state is generated, triggering entry into the collaborative control interval. When the collaborative control logic state value of the entry state is not generated and the current estimated moisture content of rice noodles is greater than the first moisture content threshold, the pre-drying control command is maintained.

6. The energy-saving integrated production control method for drying and sterilizing rice flour according to claim 3, characterized in that, The steps for quantitatively calculating the risk value of excessive surface dryness include: Extract the moisture state change data per unit time, and calculate the water loss rate and the change rate of absolute moisture content in the exhaust air per unit time based on the moisture state change data. The water loss rate per unit time, the inlet air temperature, the rate of change of absolute moisture content in the exhaust air, the reciprocal of the current estimated moisture content of the rice noodles, and the cumulative residence time of the rice noodles are all substituted into a preset risk assessment model, and the risk value of the surface being too dry is output after weighted mapping calculation.

7. The energy-saving integrated production control method for drying and sterilizing rice noodles according to claim 3, characterized in that, The steps of controlling the discharge volume of the dehumidification channel, the proportion of circulating air inside the drying chamber, the running speed of the conveyor belt, and the output of the sterilization actuator include the operation of executing circulating pneumatic feedback constraints based on sterilization priority criteria: The opening of the dehumidification valve is forced to remain unchanged or decrease, thereby limiting the amount of moisture discharged through the dehumidification channel; The opening degree of the circulating air valve is increased synchronously to improve the proportion of circulating air inside the drying chamber.

8. The energy-saving integrated production control method for drying and sterilizing rice noodles according to claim 6, characterized in that, The steps of controlling the discharge volume of the dehumidification channel, the proportion of circulating air inside the drying chamber, the running speed of the conveyor belt, and the output of the sterilization actuator include the operation of performing multi-field decoupling and dehydration sterilization speed compensation control: When it is determined that the absolute moisture content of the exhaust air is greater than the preset high humidity threshold and the risk value of the surface being too dry is greater than the preset safety risk threshold, the frequency of the circulating fan is increased, the current opening of the exhaust valve is locked, and the increase in the output of the heat source is limited. When it is determined that the amount of sterilization effect to be supplemented is greater than the preset high gap threshold and the amount of water to be removed is less than the preset small dehydration threshold, the conveyor belt running speed is reduced, the cumulative residence time of the rice noodles is extended, or the output of the sterilization actuator is increased independently. When the amount of sterilization effect to be supplemented is detected to drop to a preset zero threshold, the output of the sterilization actuator is reduced.

9. The energy-saving integrated production control method for drying and sterilizing rice flour according to claim 7, characterized in that, The steps of exiting the coordinated control zone and calculating the dehumidification energy efficiency evaluation value include: Remove the cyclic pneumatic feedback constraint based on the sterilization priority criterion, restore pneumatic regulation, and adjust the output of the sterilization actuator to zero to cut off the sterilization effect; The difference between the exhaust water carrying capacity and the exhaust water carrying capacity at the time of the previous control cycle is calculated as the dehumidification water carrying increment. The difference between the energy consumption per unit time of the production line and the energy consumption per unit time of the production line at the time of the previous control cycle is calculated as the system energy consumption increment. The ratio of the dehumidification water carrying increment to the system energy consumption increment is used as the dehumidification energy efficiency evaluation value.

10. The energy-saving integrated production control method for drying and sterilizing rice flour according to claim 9, characterized in that, The steps for determining whether to increase or decrease the dehumidification action and resetting each actuator to the material discharge standby condition include: The dehumidification energy efficiency assessment value is compared with a preset efficiency benchmark threshold. When the dehumidification energy efficiency assessment value is greater than or equal to the efficiency benchmark threshold, the frequency of the dehumidification fan is increased or the opening of the dehumidification valve is increased. When the dehumidification energy efficiency assessment value is less than the efficiency benchmark threshold, the frequency of the dehumidification fan is reduced and the opening of the dehumidification valve is decreased. When it is determined that the amount of water to be removed is less than or equal to zero and the amount of sterilization to be replenished is less than or equal to zero, the output of the heat source is forcibly adjusted to zero, the frequency of the dehumidifying fan, the frequency of the circulating fan, the opening degree of the dehumidifying valve and the opening degree of the circulating air valve are adjusted to the preset values ​​of the material discharge standby working condition, and the running speed of the conveyor belt is adjusted to the set subsequent material discharge process speed.

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