A liquid pesticide production line man-machine collaborative operation control method

Abstract

The present application relates to the field of fine chemical industry and liquid pesticide manufacturing, and particularly relates to a kind of liquid pesticide production line man-machine collaborative operation control method.The method comprises: obtaining the three-dimensional coordinates of the staff and the real-time temperature of the pipe network, when receiving the request for disassembly and washing, suspending the cooling program, maintaining the temperature of the pipe network above the critical temperature for preventing precipitation; according to the real-time flow rate and density, calculate the Reynolds number, adjust the frequency of the variable frequency water pump to maintain the turbulent flow state for emptying and flushing; obtain the real-time apparent viscosity of the outlet fluid, compare it with the pure water reference viscosity logically to determine the displacement state; when the flushing time exceeds the volume theoretical limit and the viscosity comparison fails, start the emergency refrigeration to solidify the residual pesticide liquid; when the temperature, pressure and mechanical limit signal all meet the preset safety threshold, generate and issue the maintenance instruction. The present application combines fluid mechanics and phase change principle for feedback control, effectively improving the safety of man-machine collaborative operation under high-risk working conditions.

Description

Technical Field

[0001] This invention relates to the fields of fine chemicals and liquid pesticide manufacturing, and specifically to a human-machine collaborative operation control method for a liquid pesticide production line. Background Technology

[0002] In the fields of fine chemicals and liquid pesticide manufacturing, high-concentration suspensions are a core formulation, and in-situ cleaning during production changeover is a key process to ensure the quality of multi-product co-production. Suspension pesticides are typical non-Newtonian fluids, generally exhibiting high apparent viscosity, strong thixotropy, and easy wall adhesion. In actual production line pipelines, due to the existence of complex valve arrays, multi-port manifolds, and pump dead zones, fully automated flushing alone is insufficient to remove residual materials in these dead zones. When severe wall adhesion occurs in localized areas of the pipeline, the cleaning is not thorough enough, or regular equipment maintenance is required, on-site operators must intervene in the hazardous areas to manually disassemble flanges and perform excavation and cleaning.

[0003] For the automated control of in-situ pipeline cleaning, there are already many mature applications of existing technologies. For example, Chinese patent application CN104801511A discloses an in-situ cleaning process and system, which involves introducing a first cleaning fluid for cleaning and then discharging it, followed by the introduction of an alkaline cleaning fluid for circulation cleaning. During the cleaning process, optical readings are used to measure and control the cleaning endpoint. In conventional water-soluble fluids, this control logic based on static timing rules and multi-stage liquid washing is feasible to a certain extent. Furthermore, in order to ensure the physical safety of personnel when cleaning or maintaining high-risk areas, existing industrial automation systems generally adopt a rigid protection strategy of stopping upon encountering personnel and reducing energy to ensure safety. That is, upon receiving a manual maintenance request, the heat source and fluid power source of the pipeline network are immediately cut off, and the fluid pressure and temperature in the pipeline section are forced to rapidly decrease to the human safety contact threshold, which is usually atmospheric pressure and below 40°C.

[0004] However, the aforementioned conventional automated cleaning control and cooling protection methods have serious and irreconcilable defects when dealing with special chemical fluids such as high-concentration suspending agents that are prone to thermodynamic phase changes. First, the fluidity of high-concentration suspending agents is highly dependent on specific process temperature maintenance. Once the control system forcibly shuts off the heat and suddenly cools down before manual intervention, the high-concentration liquid remaining in the pipeline will quickly cross the supersaturation curve, triggering a violent rapid cooling and crystallization effect. This will instantly condense into hard solid particles in the flange gaps and inside the valve core, which will not only cause the original automatic cleaning process to completely fail, but also easily cause mechanical jamming of the valve core or irreversible complete blockage of the pipeline, increasing the difficulty of subsequent manual unblocking and delaying the production changeover time.

[0005] Furthermore, when unknown severe blockages occur deep within the pipeline network, existing technologies lack a judgment mechanism based on objective physical extreme values, often allowing the driving pump to continuously perform ineffective dead-loop flushing. In this case, if operators blindly disassemble flanges without understanding the internal displacement status, the high-temperature residual fluid with residual pressure and toxicity accumulated inside the pipe cavity is prone to violent splashing. To prevent the risk of fluid leakage and splashing during the maintenance of special pipelines, the industry has introduced ice plug physical isolation technology. For example, Chinese patent application document with publication number CN114923524A discloses a nuclear power pipeline ice plug safety test device, which mainly uses external cooling equipment to locally apply low temperature to the outside of the pipeline, causing the internal fluid to freeze locally to form a static ice plug, thereby implementing physical isolation without stopping the reactor. However, such technologies are currently still planned proactive manual maintenance methods, and their implementation is highly dependent on pre-deployment and subjective decision-making, and do not have the adaptive interlocking interaction capability with complex chemical automatic cleaning parameters such as Reynolds number. Summary of the Invention

[0006] To address the problem that existing technologies cannot adaptively trigger safety isolation mechanisms to avoid toxic liquid splashing under extreme and abnormal operating conditions, this invention proposes a human-machine collaborative operation control method for liquid pesticide production lines, which includes:

[0007] S1. Obtain the real-time coordinates of personnel and the real-time temperature of the pipeline network. When the real-time coordinates are detected to have entered the electronic fence area and a dismantling and cleaning request is received, the cooling program is intercepted, and the pipeline network is heated and compensated to ensure that the temperature of the pipeline network is greater than or equal to the critical temperature for pesticide precipitation prevention. S2. Pump constant-temperature flushing fluid into the pipeline network through a fluid drive device, obtain the fluid motion parameters in the pipeline network, calculate the real-time Reynolds number, and perform sweeping and flushing of the pipeline network. S3. Collect the real-time viscosity at the outlet of the pipeline network, compare it with the stored reference viscosity constant, and determine the pesticide replacement state in the pipeline network. S4. Obtain the theoretical limit time of the pipeline network volume. If the actual flushing time is greater than the theoretical limit time of the volume, introduce a freezing medium into the pipeline network to cause the residual pesticide to undergo phase change and solidify. After the phase change and solidification are completed, monitor the current pressure, current temperature, and limit signal of the isolation valve in the pipeline network in real time. When the current pressure, current temperature, and limit signal all meet the safety release standard, generate and issue a maintenance command.

[0008] This invention solves the technical problem of suspending agent crystallization due to energy reduction for safety in traditional chemical control by intercepting cooling and implementing heating compensation when receiving a disassembly and cleaning request; it combines fluid dynamics calculations to perform constant temperature cleaning and uses real-time viscosity and benchmark constant comparison to determine the replacement state, thus achieving objective and accurate cleaning and effectively improving the safety and production change efficiency of human-machine collaborative operation in high-risk pesticide production lines.

[0009] Furthermore, obtaining the real-time coordinates of the personnel includes: acquiring the three-dimensional absolute coordinates of the positioning tag worn by the personnel in real time through an ultra-wideband indoor positioning network deployed at the work site, and using a filtering algorithm to smooth and denoise the three-dimensional absolute coordinates to extract stable coordinates as the real-time coordinates.

[0010] This invention effectively solves the multipath effect and electromagnetic interference caused by complex metal valve arrays in chemical workshops by using an ultra-wideband indoor positioning network and combining it with a filtering algorithm for smoothing and noise reduction. It provides a high-precision and high-stability spatial coordinate reference for the control system and avoids false triggering or missed triggering of the anti-precipitation safety interlock mechanism due to coordinate drift or burrs.

[0011] Furthermore, the electronic fence area was generated through offline experimental calibration.

[0012] Furthermore, obtaining the fluid motion parameters within the pipeline network includes: obtaining the real-time flow rate, medium density, and inner diameter of the constant-temperature flushing fluid.

[0013] Furthermore, the calculation of the real-time Reynolds number includes: obtaining the real-time viscosity at the outlet of the pipeline network, and calculating the real-time Reynolds number based on the real-time flow velocity, the medium density, the inner diameter, and the real-time viscosity.

[0014] Furthermore, the pipeline network is swept and flushed, specifically including: setting a sufficient turbulence constant as the turbulence critical value; when the real-time Reynolds number is less than the turbulence critical value, increasing the operating frequency of the fluid drive device; when the real-time Reynolds number is greater than the turbulence critical value for three consecutive control cycles, locking the current operating frequency of the fluid drive device to maintain a constant flushing state.

[0015] This invention compares the real-time Reynolds number with the full turbulence constant and dynamically adjusts the operating frequency of the fluid drive device accordingly, ensuring that the cleaning fluid in the complex pipe network always maintains a physical motion state capable of peeling off the wall-mounted cleaning solution; at the same time, locking the frequency after reaching the standard ensures both the thoroughness of constant flushing and avoids ineffective overload operation of the bottom drive motor.

[0016] Further, determining the drug replacement status within the pipeline network includes: obtaining a reference tolerance threshold based on the reference viscosity constant and a preset measurement tolerance multiple; within a preset continuous judgment time window, if the real-time viscosity is consistently less than the reference tolerance threshold, determining that the drug replacement status within the pipeline network is completely completed.

[0017] This invention calculates the baseline tolerance threshold by introducing a measurement tolerance multiplier and combines it with a continuous judgment time window for state determination, thus reserving a reasonable space for instrument noise and water quality background deviation for the ideal pure water physical value, and effectively removing signal glitches caused by electromagnetic interference and water hammer pulsation in industrial settings.

[0018] Furthermore, the measurement tolerance ratio was obtained through a pipeline background noise calibration experiment.

[0019] Furthermore, obtaining the theoretical limit time of the pipeline network includes: obtaining the measured volume of the limit physical space and the real-time flushing flow rate, and obtaining the theoretical limit time of the volume based on the measured volume of the limit physical space and the real-time flushing flow rate.

[0020] This invention obtains the measured volume of the ultimate physical space and the real-time flushing flow rate, and then determines the theoretical limit time of the volume. This provides an objective physical time scale for determining whether the conventional hydraulic flushing model has completely failed, and improves the accuracy of the system in identifying severe blockage conditions in the pipeline network.

[0021] Furthermore, a freezing medium is introduced into the pipeline network to cause the residual drug solution to undergo a phase change and solidify. Specifically, this includes: cutting off the main power supply of the fluid drive device, opening the external refrigeration regulating valve, introducing freezing liquid into the outer jacket of the pipeline network, and using the supersaturated phase change characteristics of the fluid under the heat exchange gradient drive to freeze the residual drug solution into a solid.

[0022] The present invention has the following technical effects: This invention addresses the technical shortcomings of existing technologies when personnel are inspecting high-risk chemical pipelines. The default disconnection of the heat source can induce rapid cooling and crystallization of high-concentration fluids, leading to irreversible blockage of the pipeline. By reconstructing the timing of the underlying control state machine, reverse heating compensation is performed as soon as the personnel's interaction intention is obtained, thus actively locking the flow phase of the high-concentration liquid. This invention addresses the blind spots of traditional experience-based control by establishing the driving and interlocking judgments of underlying equipment on objective fluid dynamics equations and thermodynamic constants, achieving precise emptying of dead zones in the pipeline network. Especially under abnormal operating conditions where conventional hydraulic flushing fails and internal blockage is severe, this invention transforms physical defects into defensive measures. By utilizing emergency heat exchange to trigger the phase change characteristics of the suspending fluid, it forcibly transforms highly toxic fluids that are prone to diffusion and splashing into static solids that are easy to locally and manually peel off. Attached Figure Description

[0023] Figure 1 This is a flowchart of a human-machine collaborative operation control method for a liquid pesticide production line provided in an embodiment of the present invention; Figure 2 This is a comparison diagram of the effects of the prior art provided in the embodiments of the present invention and the present invention. Detailed Implementation

[0024] This invention provides a human-machine collaborative operation control method for a liquid pesticide production line, referring to... Figure 1 This includes steps S1-S4: S1: Data Acquisition and Preprocessing.

[0025] Specifically, the system obtains the real-time coordinates of personnel and the real-time temperature of the pipeline network. When the system detects that the real-time coordinates have entered the electronic fence area and receives a dismantling and cleaning request, it intercepts the cooling program and performs heating compensation control on the pipeline network to make the temperature of the pipeline network equal to the critical temperature for pesticide precipitation prevention.

[0026] First, the real-time location information of on-site workers is obtained. In this embodiment, it is preferable to deploy an ultra-wideband indoor positioning network on the roof of the factory building in the industrial site. On-site workers wear explosion-proof positioning tags, and the positioning base station collects the three-dimensional absolute coordinates of the positioning tags in real time through wireless radio frequency signals. Due to the presence of numerous metal pipes and variable frequency motors in industrial sites, multipath effects and electromagnetic interference are generated, resulting in a large amount of drift data and glitches in the acquired three-dimensional absolute coordinates. To eliminate these interferences, the control system internally runs a filtering algorithm to smooth and denoise the three-dimensional absolute coordinates. In this embodiment, the Kalman filter algorithm is preferred as the denoising method. The control system uses the prediction and update mechanisms of the Kalman filter algorithm to remove abrupt changes in the spatial trajectory and finally extracts stable coordinate data as real-time coordinates.

[0027] While acquiring personnel location, the control system continuously acquires the real-time temperature of the pipeline network. In this embodiment, a high-precision temperature sensor is preferably installed in a patch manner at the fluid inlet and outlet of the outer wall of the pipeline network, combined with a platinum resistance temperature sensor to obtain a physical response signal with high linearity. Then, the voltage signal of the temperature sensor is transmitted to the analog input module of the programmable logic controller, and then the voltage signal is linearly converted into the real-time temperature data of the pipeline network through the analog-to-digital conversion channel.

[0028] To determine whether personnel have entered a hazardous operating space, it is necessary to monitor whether their real-time coordinates have entered a specific electronic fence area. This electronic fence area is not a subjectively defined geometric shape, but a physical envelope surface generated through offline experimental calibration. The specific steps are as follows: Engineers first place multiple positive sample points at the mechanical and physical boundaries of the pipeline network, such as flanges, and multiple negative sample points at safe passages away from the pipeline network. Then, the control system traverses different spatial tolerance radius parameters. In this embodiment, it is preferred to gradually increase the radius from 0.1m to 1.5m. The control system continuously records the false alarm rate and false negative rate generated by the positioning network under different spatial tolerance radius parameters, and then calculates the precision and recall. The control system extracts the value that maximizes the harmonic mean of the two and uses it as the optimal equilibrium point radius. Finally, the system uses the optimal equilibrium point radius to perform envelope expansion calculation on the three-dimensional digital model of the pipeline network to generate the final electronic fence area.

[0029] When the system detects that the real-time coordinates have entered the electronic fence area and simultaneously receives a disassembly and cleaning request signal sent by the operator through a portable terminal, the control system triggers a reverse thermodynamic protection mechanism. Under conventional chemical interlocking logic, the equipment shutdown will trigger a default cooling action. However, in this embodiment, the system's underlying controller will immediately intercept the cooling program and forcibly cut off the external cooling water valve.

[0030] Next, the control system performs heating compensation control on the pipeline network; it retrieves the factory-set anti-precipitation critical temperature of this batch of suspension pesticides as the control target threshold; in this embodiment, a proportional-integral-derivative control algorithm is preferably used to adjust the input power of the external heating jacket of the pipeline network. The control system outputs a dynamic voltage signal to the heating element based on the deviation between the real-time temperature and the target threshold, so that the temperature of the pipeline network is equal to the pesticide anti-precipitation critical temperature; through the linkage of the above hardware and algorithm, the present invention actively locks the flow phase of the high-concentration pesticide fluid, avoiding rapid cooling precipitation and crystallization blockage of the liquid due to sudden cooling in the dead corners of the pipeline network, and providing the necessary thermodynamic conditions for fluid replacement in subsequent steps.

[0031] S2: Thermostatic sweeping and flushing based on fluid dynamics feedback.

[0032] Specifically, a constant-temperature flushing fluid is pumped into the pipeline network through a fluid-driven device to obtain the fluid motion parameters within the pipeline network, calculate the real-time Reynolds number, and perform sweeping and flushing of the pipeline network.

[0033] After the temperature is locked, the control fluid drive device is started to pump the constant temperature flushing fluid into the pipeline. In this embodiment, an industrial variable frequency pump is preferred as the fluid drive device. In order not to disrupt the thermodynamic equilibrium state established in the previous step, pure water heated by an external heat exchanger is used as the constant temperature flushing fluid. At the same time, the initial physical temperature of the constant temperature flushing fluid is adjusted to be equal to the critical temperature for pesticide precipitation prevention.

[0034] During the flushing operation, the control system continuously acquires fluid motion parameters within the pipeline network. The system first retrieves the pre-mapped and recorded pipeline inner diameter data from the underlying read-only memory, and then retrieves the medium density constant corresponding to pure water based on the current constant temperature. In this embodiment, a Coriolis mass flow meter is preferably installed at the front end of the main pipeline of the pipeline network. The real-time flushing flow rate is collected at high frequency by the flow meter, and the real-time flushing flow rate is divided by the cross-sectional area of ​​the pipeline network to obtain the real-time flow rate of the constant temperature flushing liquid. At the same time, the real-time viscosity of the mixture is obtained by the sensing device deployed at the end of the pipeline network.

[0035] After obtaining the basic physical parameters, the floating-point arithmetic unit inside the control system begins to perform calculations to calculate the real-time Reynolds number. The specific calculation logic is to multiply the real-time flow velocity with the medium density and the inner diameter of the pipe network, divide the product by the real-time viscosity at the pipe network outlet, and finally obtain the quotient as the real-time Reynolds number in the current pipe network. This calculation method, which uses dynamic viscosity as the divisor, can reflect the real flow resistance generated by high-concentration liquid in complex pipe networks.

[0036] Based on this, the control system performs adaptive sweeping and flushing of the pipeline network. In this embodiment, the sufficient turbulence constant in the fluid mechanics axiom is preferably set as the turbulence critical value. The bottom logic comparator compares the real-time Reynolds number with the turbulence critical value at high frequency. When the calculated real-time Reynolds number is less than the turbulence critical value, it indicates that the current flushing kinetic energy is insufficient to remove the sticky liquid adhering to the dead corner of the pipe wall. The control system then outputs a deviation adjustment signal to increase the operating frequency of the fluid drive device. The increase in operating frequency will simultaneously increase the flushing flow rate and the Reynolds number.

[0037] Continuous status monitoring and frequency adjustment are performed. When the control system detects that the real-time Reynolds number is greater than the turbulence critical value for three consecutive control cycles, it determines at the logic level that a stable forced flushing flow field has been formed inside the pipeline. At this time, the controller immediately locks the current operating frequency of the fluid drive device and maintains a constant flushing state without increasing energy consumption, so as to smoothly push the easily crystallized liquid out of the pipeline.

[0038] As an equivalent extension with industrial practical value, when the production line faces special liquid pesticides that undergo violent emulsification reactions upon contact with water, this invention provides a matching physical alternative: the fluid drive device can be replaced with a high-pressure gas proportional valve, and the constant-temperature rinsing liquid can be replaced with a high-pressure pure gas heated to the critical temperature for preventing pesticide precipitation, such as inert high-pressure pure nitrogen. This alternative design, while using the same fluid dynamics control logic, eliminates the risk of chemical heating of special agents, ensuring the broad applicability of the entire solution.

[0039] S3: Determination of drug replacement status.

[0040] Specifically, the real-time viscosity at the outlet of the pipeline is collected and compared with the stored reference viscosity constant to determine the drug displacement status within the pipeline.

[0041] During the flushing process, the control system needs to determine whether the residual pesticide solution in the pipeline has been completely replaced. First, the real-time viscosity at the outlet of the pipeline is collected by a sensing device. In this embodiment, an ultrasonic online viscometer is preferably installed as a sensing device on the straight pipe section after the main drain valve. The ultrasonic online viscometer converts the damping attenuation state of the ultrasonic wave in the fluid into an electrical signal and transmits the electrical signal to the industrial controller. The analysis module inside the industrial controller converts the received electrical signal into a real-time viscosity value. At the same time, the control system retrieves the reference viscosity constant pre-stored in the underlying register. This reference viscosity constant is an objective physical constant value of pure water medium at the critical temperature for pesticide precipitation prevention. In this embodiment, this constant is preferably obtained through the basic thermodynamic physical property table and fixed in the read-only memory.

[0042] The control system then compares the real-time viscosity with the reference viscosity constant. In order to remove the instrument noise and water dust interference in the real industrial environment, the preset measurement tolerance ratio is first retrieved. The underlying floating-point arithmetic unit of the control system multiplies the reference viscosity constant with the preset measurement tolerance ratio to obtain the reference tolerance threshold.

[0043] It should be noted that the tolerance ratio was obtained through a pipeline background noise calibration experiment, and the specific steps are as follows: With the pipeline network idle and shut down, engineers injected pesticide-free pure water into the network for normalized empty circulation. In a real electromagnetic environment where all large variable frequency motors and mixing tanks were running simultaneously, they recorded the viscosity noise waveform fluctuation sequence of five cycles output by the viscometer. The microprocessor calculated the set of ratios between the steady-state extreme value of this fluctuation sequence and the reference viscosity constant. From this set of ratios, the optimal envelope ratio that can smoothly cover all electromagnetic pulse peaks was extracted, and finally, this optimal envelope ratio was set as the measurement tolerance ratio.

[0044] After obtaining the baseline tolerance threshold, the control system enters the final state machine determination stage. The system's hardware logic comparator begins to check the real-time viscosity value at high frequency, and the comparator determines whether the real-time viscosity is less than the baseline tolerance threshold. In order to eliminate transient signal glitches caused by fluid pulsation and sensor water hammer effect, the system has a built-in continuous judgment time window mechanism. In this embodiment, the continuous judgment time window is preferably set to five hardware scan cycles. The system continuously monitors the output level of the comparator. If the real-time viscosity is less than the baseline tolerance threshold within the continuous judgment time window, the main control state machine triggers internal actions. The control system determines at the logic level that the drug replacement state in the pipeline is completely completed, and simultaneously flips the release flag bit of the internal state machine.

[0045] Furthermore, for special agents that are prone to emulsification upon contact with water, this invention provides a corresponding replacement judgment alternative scheme; under the special working condition where the system uses high-pressure pure gas instead of pure water for constant temperature rinsing, the above-mentioned viscosity comparison action based on fluid mechanics is simultaneously switched to gas concentration comparison action; in this embodiment, a volatile organic compound concentration sensor is preferably installed at the outlet end of the air exhaust valve in the pipeline network, and the control system collects the concentration of organic matter in the gas at the outlet of the exhaust valve at high frequency, analyzes the changing trend of the organic matter concentration, and when the organic matter concentration continues to fall and finally stabilizes within the allowable tolerance range of the environmental background, the control system also determines that the replacement state of the drug solution in the pipeline network is completely completed.

[0046] S4: Rinse timeout determination and emergency cooling curing.

[0047] Specifically, the theoretical limit time of the pipeline network volume is obtained. If the actual flushing time is greater than the theoretical limit time, a refrigerant is introduced into the pipeline network to cause the residual liquid to undergo phase change and solidify. After the phase change and solidification are completed, the current pressure, current temperature and limit signal of the isolation valve of the pipeline network are monitored in real time. When the current pressure, current temperature and limit signal all meet the safety release standard, a maintenance command is generated and issued.

[0048] The high-frequency timer inside the control system accumulates and records the actual flushing time of the flushing operation in real time. To determine whether an unknown severe blockage has occurred inside the pipeline network, the theoretical limit time of the pipeline network volume is first obtained, as follows: The measured volume of the ultimate physical space in the underlying memory is retrieved. This measured volume of the ultimate physical space includes the sum of the three-dimensional volumes of all known blind pipes and isolation valve dead zones in the pipeline network. The real-time flushing flow rate output by the flow meter at the front end of the pipeline network is acquired simultaneously. Then, the underlying arithmetic unit of the control system performs a floating-point division operation. The arithmetic unit divides the measured volume of the ultimate physical space by the real-time flushing flow rate. The system sets the objective theoretical physical lower limit time obtained by the division operation as the volume theoretical limit time.

[0049] Next, the control system compares the actual flushing time with the theoretical limit time of the volume at high frequency. If it is determined that the actual flushing time is greater than the theoretical limit time of the volume, and the state machine in the previous step does not give a release signal that the replacement is completely completed, it indicates that the hydraulic flushing model inside the pipeline has failed. The system triggers the underlying phase change defense mechanism and introduces a freezing medium into the pipeline to cause the residual drug solution to undergo phase change and solidify.

[0050] In terms of specific actions, the control system first cuts off the main power supply of the fluid drive device through a relay, and at the same time sends a level command to the external refrigeration servo mechanism to fully open the external refrigeration regulating valve and introduce a large flow of refrigerant into the outer jacket of the pipeline network. In this embodiment, a low-temperature industrial refrigerant of -5℃ is preferred as the refrigerant. By utilizing the supersaturated phase change characteristics of the suspended pesticide fluid under the drive of a large heat exchange gradient, the highly toxic liquid pesticide remaining in the pipeline valve core is caused to instantly cross the supersaturation curve. The residual liquid is frozen into a hard solid plate under rapid cooling. This action transforms the high-risk fluid into a static solid that is easy to peel off, eliminating the hidden danger of liquid pesticide leakage and splashing.

[0051] After confirming the completion of the above phase change curing action, the final safety interlock monitoring stage begins. The control system monitors the current pressure and temperature of the pipeline network in real time through the instrument network, and reads the limit signal of the pipeline isolation valve. In this embodiment, a dual-valve with venting isolation component is preferably used as the physical isolation device for the pipeline network. The logic comparator of the control system checks at high frequency whether the above physical parameters simultaneously meet the safety release criteria.

[0052] The safety release standard specifically includes three rigid interlocking conditions. The first condition is that all mechanical limit switches of the isolation valve return a fully closed physical level signal to the controller. The second condition is that the current temperature is lower than the physical boundary temperature for preventing burns; in this embodiment, the physical boundary temperature is preferably set to 40°C. The third condition is that the current pressure is not higher than the atmospheric pressure limit; in this embodiment, the atmospheric pressure limit is preferably set to 105 kPa. Only when the current pressure, current temperature, and limit signals all meet the above safety release standards will the central control system grant permissions at the lower level. The system then generates and sends maintenance instructions to the smart terminals carried by the on-site operators. After receiving the maintenance instructions, the on-site maintenance personnel can perform manual disassembly and unblocking operations in a safe physical environment.

[0053] Figure 2 The diagram shows a comparison of the effects of the prior art and the present invention provided in the embodiments of the present invention. It can be seen that the prior art immediately cuts off the heating and power source when it receives a dismantling and cleaning request, causing the pipeline temperature to drop rapidly below the critical temperature for preventing precipitation, which can easily lead to rapid cooling and crystallization of residual liquid and physical dead zone blockage. In contrast, the present invention actively intercepts the cooling process after receiving the request. Through frequency conversion dynamic optimization and reverse heating compensation, the pipeline is maintained in a fully turbulent state to perform isothermal sweeping and replacement until the theoretical limit time of volume is reached and the pipeline is completely emptied. Only then is the heat source actively removed and safe cooling is performed to release the pipeline, thus resolving the thermodynamic contradiction between cooling for safety and preventing crystallization and blockage.

Claims

1. A human-machine collaborative operation control method for a liquid pesticide production line, characterized in that, include: S1. Obtain the real-time coordinates of personnel and the real-time temperature of the pipeline network. When the real-time coordinates are detected to have entered the electronic fence area and a dismantling and cleaning request is received, the cooling program is intercepted, and the pipeline network is heated and compensated to ensure that the temperature of the pipeline network is greater than or equal to the critical temperature for pesticide precipitation prevention. S2. Pump a constant-temperature flushing liquid into the pipeline network using a fluid drive device, obtain the fluid motion parameters within the pipeline network, calculate the real-time Reynolds number, and perform sweeping and flushing of the pipeline network, including: setting a sufficient turbulence constant as the turbulence critical value; increasing the operating frequency of the fluid drive device when the real-time Reynolds number is less than the turbulence critical value; locking the current operating frequency of the fluid drive device and maintaining a constant flushing state when the real-time Reynolds number is greater than the turbulence critical value for three consecutive control cycles. S3. Collect the real-time viscosity at the outlet of the pipeline network and compare it with the stored reference viscosity constant to determine the pesticide displacement state within the pipeline network. S4. Obtain the theoretical volume limit time of the pipeline network, including: retrieving data from the underlying memory. The measured volume of the ultimate physical space includes the sum of the three-dimensional volumes of all known blind pipes and dead zones of isolation valves within the pipeline network. Simultaneously, the real-time flushing flow rate output from the flow meter at the pipeline's front end is acquired. Subsequently, the system's underlying arithmetic unit performs a floating-point division operation, dividing the measured volume of the ultimate physical space by the real-time flushing flow rate. The system sets the objective theoretical physical lower limit time obtained from the division operation as the volumetric theoretical limit time. If the actual flushing time exceeds the volumetric theoretical limit time, a refrigerant is introduced into the pipeline network to cause the residual drug solution to undergo phase change solidification. This includes: cutting off the main power supply of the fluid drive device, opening the external refrigeration regulating valve, introducing refrigerant into the external jacket of the pipeline network, and utilizing the supersaturated phase change characteristics of the fluid under heat exchange gradient drive to freeze the residual drug solution into a solid. After the phase change solidification is completed, the current pressure, current temperature, and limit signal of the isolation valve in the pipeline network are monitored in real time. When the current pressure, current temperature, and limit signal all meet the safety release criteria, a maintenance command is generated and issued.

2. The human-machine collaborative operation control method for a liquid pesticide production line according to claim 1, characterized in that, The process of obtaining the real-time coordinates of the personnel includes: acquiring the three-dimensional absolute coordinates of the positioning tag worn by the personnel in real time through an ultra-wideband indoor positioning network deployed at the work site; using a filtering algorithm to smooth and denoise the three-dimensional absolute coordinates; and extracting stable coordinates as the real-time coordinates.

3. The human-machine collaborative operation control method for a liquid pesticide production line according to claim 1, characterized in that, The electronic fence area was generated through offline experimental calibration.

4. The human-machine collaborative operation control method for a liquid pesticide production line according to claim 1, characterized in that, Obtaining the fluid motion parameters within the pipeline network includes: obtaining the real-time flow rate and medium density of the constant-temperature flushing fluid, as well as the inner diameter of the pipeline network.

5. The human-machine collaborative operation control method for a liquid pesticide production line according to claim 4, characterized in that, The calculation of the real-time Reynolds number includes: obtaining the real-time viscosity at the outlet of the pipeline network, and calculating the real-time Reynolds number based on the real-time flow velocity, the medium density, the inner diameter, and the real-time viscosity.

6. The human-machine collaborative operation control method for a liquid pesticide production line according to claim 1, characterized in that, Determining the drug replacement status within the pipeline network includes: obtaining a reference tolerance threshold based on the reference viscosity constant and a preset measurement tolerance ratio; within a preset continuous judgment time window, if the real-time viscosity is consistently less than the reference tolerance threshold, determining that the drug replacement status within the pipeline network is completely completed.

7. The human-machine collaborative operation control method for a liquid pesticide production line according to claim 6, characterized in that, The measurement tolerance ratio was obtained through a pipeline background noise calibration experiment.

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