VCM rectification high-boiling column kettle temperature liquid level parameter coordination control method and system

Abstract

This application discloses a method and system for coordinated control of reboiler temperature and level parameters in a VCM distillation high-boiling-point column. In addition to timed discharge during automatic blowdown of the high-boiling-point column, this method adds reboiler level and temperature judgment. Based on the changes in reboiler temperature and level during discharge, the opening and closing speed of the automatic blowdown valve are controlled. During blowdown, the hot water valve controls the reboiler temperature. During non-blowdown processes, a transition control is added, adjusting the hot water valve opening based on reboiler temperature changes. At the end of the transition period, the hot water valve controls the reboiler level, with the feed valve acting as feedforward. The high-boiling-point condenser regulating valve controls the condenser pressure. The high-boiling-point reflux regulating valve controls the reflux tank level, with the column top temperature acting as feedforward. This method effectively achieves automatic blowdown of the high-boiling-point column, ensuring the balance of various indicators and keeping all parameters within reasonable ranges, thus guaranteeing the safe operation of the high-boiling-point column.

Description

Technical Field

[0001] This invention relates to the field of VCM distillation high-boiling column production technology, and in particular to a method and system for coordinated control of VCM distillation high-boiling column bottom temperature and liquid level parameters. Background Technology

[0002] With the continuous development of industrial technology, the requirements for the production process of VCM distillation high-boiling-point columns are becoming increasingly stringent. The control of column bottom temperature and liquid level are crucial parameters in the VCM distillation high-boiling-point column production process, and their stability and accuracy directly affect product quality and yield.

[0003] However, in actual production, the high boiling point tower is manually drained at regular intervals. Under the condition that the parameters such as the tower bottom temperature, tower top pressure, and tower top temperature are met, the drain valve is opened at a certain degree and maintained for a period of time to complete the draining. If the high boiling point tower operating parameters are not met, the draining is stopped immediately.

[0004] In existing technologies, timed blowdown does not take into account the impact of the high-boiling-point tower's operating load on the high-boiling-point substances, which may result in untimely blowdown, as well as over- or under-blowdown. During the blowdown process, the operating parameters of the high-boiling-point tower fluctuate greatly, and sometimes it may exceed the target, which will affect the product quality. Summary of the Invention

[0005] Based on this, this application provides a method and system for coordinated control of reboiler temperature and liquid level parameters in a VCM distillation high-boiling-point column. This system effectively achieves automatic blowdown of the high-boiling-point column, ensuring the balance of various indicators and keeping all parameters within reasonable ranges during the automatic blowdown process, thus guaranteeing the production safety of the high-boiling-point column. The implementation of automatic blowdown control enables near-unmanned operation of the high-boiling-point column, improving production intelligence, reducing the labor intensity of workers, and ensuring product quality.

[0006] Firstly, a method for coordinated control of reboiler temperature and level parameters in a high-boiling-point VCM distillation column is provided, the method comprising:

[0007] The control of the high boiling point tower drain valve is specifically achieved by determining whether the drain valve is open or closed by acquiring the high boiling point tower bottom liquid level and tower bottom temperature values, and by controlling the opening degree of the drain valve according to the rate of change of the high boiling point tower bottom liquid level and the rate of change of the tower bottom temperature during the high boiling point tower drain process.

[0008] The hot water regulating valve of the high boiling tower is controlled by using the feed valve as a feedforward. During the high boiling tower blowdown process, the high boiling tower bottom temperature is used as the target control point, and during the non-high boiling tower blowdown process, the high boiling tower bottom liquid level is used as the target control point.

[0009] The pressure of the high-boiling-point tower condenser is controlled by a single-loop condenser control valve at the top of the high-boiling-point tower.

[0010] The reflux regulating valve is controlled by the liquid level in the reflux tank, and the top temperature of the high-boiling tower is used as the feedforward for the liquid level in the reflux tank.

[0011] Optionally, in the control of the high-boiling-point tower drain valve, the opening or closing of the drain valve is determined by acquiring the high-boiling-point tower bottom liquid level value and the tower bottom temperature value, including:

[0012] When the liquid level in the bottom of the high-boiling tower is higher than the set value and the temperature in the bottom of the tower continues to rise, it is determined that the drain valve needs to be opened.

[0013] When the liquid level in the bottom of the high-boiling tower is lower than the set value and the temperature in the bottom of the tower is stable, it is determined that the drain valve needs to be closed.

[0014] Optionally, the method further includes:

[0015] Set the minimum and maximum sewage discharge intervals.

[0016] Optionally, in the control of the hot water regulating valve for the high-boiling-point tower, the high-boiling-point tower bottom temperature is used as the target control point during the high-boiling-point tower blowdown process, and the high-boiling-point tower bottom liquid level is used as the target control point during the non-high-boiling-point tower blowdown process, including:

[0017] During the high boiling point tower blowdown process, the goal is to control the tower bottom temperature, and the opening of the hot water regulating valve is dynamically adjusted according to the real-time temperature value.

[0018] During the non-high boiling tower blowdown process, the goal is to control the liquid level in the high boiling tower bottom. The opening of the hot water regulating valve is dynamically adjusted based on the real-time liquid level value. At the same time, the opening of the feed valve is used as a feedforward signal to predict and control the feed and evaporation rate of the high boiling tower.

[0019] Optionally, in the control of the hot water regulating valve of the high-boiling tower, the method further includes:

[0020] The control point of the tower bottom temperature is dynamically adjusted in real time based on the average temperature over a preset period before the start of the blowdown, the rate of temperature change in the tower bottom after the blowdown, and the process parameter control indicators.

[0021] Optionally, in the control of the hot water regulating valve of the high-boiling tower, the method further includes:

[0022] After the high boiling point tower finishes its blowdown process, the blowdown valve is closed, and after a preset delay, the hot water control switches to control the liquid level in the high boiling point tower bottom.

[0023] Optionally, in the reflux regulating valve control, the reflux tank level is specifically the controlled object, and the high-boiling tower top temperature is used as feedforward for the reflux tank level control, including:

[0024] Using the reflux tank level as the control object, the target value of the reflux tank level is dynamically adjusted based on the real-time monitoring of the high-boiling tower feed rate, evaporation rate, and the high-boiling tower top temperature when the condensation pressure at the top of the tower is stable.

[0025] Optionally, the method further includes:

[0026] The process data of the high boiling tower blowdown valve control, high boiling tower hot water regulating valve control, condensate regulating valve control, and reflux regulating valve control are visualized.

[0027] Secondly, a coordinated control system for the temperature and level parameters of the reboiler in a high-boiling-point VCM distillation column is provided, the system comprising:

[0028] The high boiling point tower drain valve control module is used to determine whether the drain valve is open or closed by acquiring the high boiling point tower bottom liquid level and tower bottom temperature values, and to control the opening degree of the drain valve according to the rate of change of the high boiling point tower bottom liquid level and the rate of change of the tower bottom temperature during the high boiling point tower drain process.

[0029] The hot water regulating valve control module for high boiling tower is used to control the high boiling tower bottom temperature as the target control point during the high boiling tower blowdown process and the high boiling tower bottom liquid level as the target control point during the non-high boiling tower blowdown process.

[0030] The condenser regulating valve control module is used to control the pressure of the high-boiling tower condenser through a single-loop condenser regulating valve at the top of the high-boiling tower.

[0031] The reflux regulating valve control module is used to control the reflux tank level by using the high-boiling tower top temperature as feedforward for the reflux tank level.

[0032] The beneficial effects of the technical solutions provided in this application include at least the following:

[0033] (1) It solves the problem that the balance of the entire tower is broken when the high boiling tower is frequently discharged, resulting in insufficient safe, stable and economical operation.

[0034] (2) The problem of balancing and coordinating the temperature and liquid level of the high-boiling tower bottom has been solved.

[0035] (3) It solves the problem of low automatic operation rate of high boiling tower and inability to put it into automatic control under full operating conditions. Attached Figure Description

[0036] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0037] Figure 1 A process flow diagram of the VCM high boiling tower provided in the embodiments of this application;

[0038] Figure 2 The logic control diagram of the high boiling tower drain valve provided in the embodiments of this application;

[0039] Figure 3 A control diagram of a high-boiling-point hot water valve provided in an embodiment of this application;

[0040] Figure 4 A control diagram of the high-boiling-point tower condenser regulating valve provided in an embodiment of this application;

[0041] Figure 5 A control diagram of the reflux valve for a high-boiling tower provided in an embodiment of this application. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0043] In the description of this invention, the terms “comprising,” “having,” and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units that are expressly listed, but may also include other steps or units that are not expressly listed but are inherent to these processes, methods, products, or apparatuses, or steps or units added based on further optimizations of the inventive concept.

[0044] The technology in this application is applied to the system coordination control of parameters such as the temperature and level of the column bottom in the production process of VCM distillation high boiling column. It is especially applied to the coordination control when the high boiling column is not discharged in time or cleanly during the high boiling column discharge process, resulting in large fluctuations in parameters such as the temperature and level of the column bottom and making it difficult to guarantee product quality.

[0045] (1) Currently, when the temperature and liquid level of the high-boiling column in VCM distillation are stable, the control indicators of the high-boiling column basically meet the production requirements and can be automatically controlled. However, when the operating conditions of the high-boiling column change, especially during the high-boiling column sludge discharge process, the temperature of the high-boiling column bottom fluctuates greatly and the pressure at the top of the column fluctuates greatly, which leads to the production parameters exceeding the indicators and easily causes the product quality to be unqualified. At the same time, since the high-boiling column sludge discharge is generally done manually, the discharge is highly arbitrary, which may lead to untimely discharge, excessive discharge, or incomplete discharge.

[0046] (2) The high boiling tower wastewater discharge process and the high boiling tower bottom control parameters are controlled in isolation; during the high boiling tower wastewater discharge process, the high boiling tower control parameters fluctuate greatly, which cannot effectively guarantee product quality.

[0047] (3) Due to the untimely adjustment of constantly changing operating conditions during manual sewage discharge, abnormal parameters of the high-boiling-point tower are caused, such as large fluctuations in parameters like tower bottom temperature, tower bottom liquid level, tower top pressure, and tower top temperature, making it difficult to guarantee product quality. The existence of these problems will have varying degrees of impact on the safe and economical operation of the high-boiling-point tower.

[0048] Specifically, this invention can be applied to a VCM high-boiling-point tower process system, wherein the system consists of five main parts: a high-boiling-point tower, a reboiler, a condenser, a reflux tank, and three towers, as detailed below. Figure 1 As shown. The raw material for the low-boiling-point tower passes through the feed valve (high-boiling-point tower feed valve) at the bottom of the low-boiling-point tower and enters the high-boiling-point tower for further processing. The hot water valve controls the heating of the bottom of the high-boiling-point tower through the reboiler to evaporate the light components, which then rise, while the heavy components remain at the bottom. The light components are condensed by 5°C chilled water in the condenser at the top of the tower and then enter the reflux tank. The non-condensable gas enters the gas holder for further processing. Part of the finished product in the reflux tank is returned through the high-boiling-point tower reflux valve, and the other part is obtained as finished product through the finished product collection valve. The high-boiling-point material at the bottom of the high-boiling-point tower enters the three towers for further processing through the drain valve.

[0049] This application primarily addresses the coordinated control of operating parameters of a high-boiling-point (HBO) distillation tower during the blowdown process. The overall technical solution includes a reorganization of the HBO distillation tower blowdown control logic. During blowdown, the application monitors the rate of change of the tower bottom liquid level and the rate of change of the tower bottom temperature, while simultaneously adjusting the corresponding parameter control points according to the HBO distillation tower parameter control requirements. Furthermore, during blowdown, the main circuit control of the hot water valve is changed from controlling the HBO distillation tower bottom liquid level to controlling the tower bottom temperature. Specifically, this may include the following four control processes:

[0050] High boiling tower drain valve control:

[0051] The opening or closing of the drain valve is determined by obtaining the liquid level and temperature values ​​of the high boiling point tower bottom. The opening degree of the drain valve is controlled according to the rate of change of the liquid level and temperature of the high boiling point tower bottom during the draining process.

[0052] Specifically, due to the separation of light and heavy components at the bottom of the high-boiling-point column, heavy components accumulate continuously, leading to a continuous increase in the temperature at the bottom of the column. If the feed rate to the high-boiling-point column remains stable, it will be difficult to maintain the liquid level in the column bottom. When the control parameters of the high-boiling-point column become abnormally high, the balance inside the column will be disrupted.

[0053] The high-boiling-point tower drain valve is controlled using override control. The valve's opening and closing are determined by the tower's bottom liquid level and temperature. During the draining process, the valve opening is controlled based on the rate of change of the tower's bottom liquid level and temperature. Figure 2 The logic control diagram of the high boiling tower drain valve in this application is given.

[0054] In an optional embodiment of this application, when the liquid level in the bottom of the high-boiling tower is higher than the set value and the bottom temperature continues to rise, it is determined that the drain valve needs to be opened; when the liquid level in the bottom of the high-boiling tower is lower than the set value and the bottom temperature is stable, it is determined that the drain valve needs to be closed.

[0055] High-boiling-point hot water regulating valve control:

[0056] The feed valve is used as a feedforward. During the high-boiling-point tower sludge discharge process, the high-boiling-point tower bottom temperature is used as the target control point, while during the non-high-boiling-point tower sludge discharge process, the high-boiling-point tower bottom liquid level is used as the target control point.

[0057] Specifically, the hot water regulating valve of the high boiling tower controls the temperature of the high boiling tower bottom (dynamic control point) under the blowdown condition, and controls the liquid level of the high boiling tower bottom under the non-blowdown condition. Since the feed components and feed material affect the control parameters of the high boiling tower, but the feed components of the high boiling tower are guaranteed in the distillation process of the low tower, the high boiling tower feed valve (low tower feed valve) is used as a feedforward.

[0058] The dynamic control point of the high-boiling-point column reboiler temperature is dynamically adjusted based on the average temperature recorded over a preset time period before the start of blowdown, the rate of change of column reboiler temperature after the start of blowdown, and the process parameter control index of the high-boiling-point column reboiler temperature. The preset time period can be three minutes.

[0059] After the high-boiling-point column finishes its blowdown process, the blowdown valve is closed. After a delay, the column bottom level is switched to hot water control. This is because closing the blowdown valve causes the high-boiling-point column level to rise rapidly, so a delay is needed before switching from controlling the column bottom temperature to controlling the column bottom level. Figure 3 A control diagram of the hot water valve for the high-boiling tower provided in an embodiment of this application is given.

[0060] In optional embodiments of this application, during the high-boiling-point tower blowdown process, the opening of the hot water regulating valve is dynamically adjusted based on the real-time temperature value to control the high-boiling-point tower bottom temperature; during the non-high-boiling-point tower blowdown process, the opening of the hot water regulating valve is dynamically adjusted based on the real-time liquid level value to control the high-boiling-point tower bottom liquid level; simultaneously, the opening of the feed valve is used as a feedforward signal to predict and control the feed and evaporation rates of the high-boiling-point tower.

[0061] Condensation regulating valve control:

[0062] Specifically, the pressure of the high-boiling-point column condenser is controlled by a single-loop condenser regulating valve at the top of the column. The high-boiling-point column condenser regulating valve uses a single-loop control system to regulate the pressure of the high-boiling-point column condenser. For example... Figure 4 A control diagram of the high-boiling-point tower condenser regulating valve provided in an embodiment of this application is given.

[0063] Reflux regulating valve control:

[0064] The liquid level in the reflux tank is the controlled object, and the top temperature of the high-boiling tower is used as the feedforward for controlling the liquid level in the reflux tank.

[0065] Specifically: The reflux regulating valve of the high-boiling-point column is controlled by the liquid level in the reflux tank. The liquid level in the reflux tank is significantly affected by the feed rate and evaporation rate of the high-boiling-point column, causing large fluctuations that impact the safe operation of the column. When the condensing pressure at the top of the high-boiling-point column is stable, the temperature at the top of the column is relatively stable; therefore, the temperature at the top of the column is used as a feedforward for the reflux tank liquid level. Figure 5 A control diagram of the reflux valve for the high boiling tower provided in this application embodiment is given.

[0066] The following describes the specific implementation process of applying the above method, specifically in the control of a high-boiling point tower in a polyvinyl chloride production workshop:

[0067] In the existing high boiling point tower blowdown control, the high boiling point tower is manually blowdowned at regular intervals; during the blowdown process, the hot water valve is used to control the tower bottom liquid level, and during non-blowdown processes, the high boiling point tower hot water valve controls the high boiling point tower bottom liquid level; the high boiling point tower condenser regulating valve controls the high boiling point tower condenser pressure; and the high boiling point tower reflux valve is manually controlled.

[0068] This method achieves automatic blowdown of the high-boiling-point tower. In addition to the original timed blowdown, it adds judgments on the high-boiling-point tower bottom liquid level and temperature. Based on the changes in bottom liquid level and temperature during the blowdown process, it controls the opening and closing speed of the automatic blowdown valve. It also adds minimum and maximum blowdown time intervals and increases the minimum blowdown time. During the blowdown process, the hot water valve controls the high-boiling-point tower bottom temperature. During non-blowdown processes, a transition control is added, adjusting the hot water valve opening based on changes in the high-boiling-point tower bottom temperature. At the end of the transition time, the hot water valve controls the high-boiling-point tower bottom liquid level. The high-boiling-point tower feed valve (low-level tower feed valve) acts as feedforward. The high-boiling-point tower condenser regulating valve controls the high-boiling-point tower condenser pressure. The high-boiling-point tower reflux regulating valve controls the reflux tank level, with the high-boiling-point tower top temperature acting as feedforward.

[0069] In summary, this application introduces the high-boiling tower liquid level change rate and high-boiling tower temperature change rate into the high-boiling tower sludge discharge process to promptly determine the sludge discharge status, ensuring that high-boiling substances are discharged completely and without excessive discharge. This avoids low tower efficiency due to excessive discharge and high tower bottom temperature due to incomplete discharge, which would compromise product quality.

[0070] Meanwhile, the high-boiling-point tower blowdown process introduces automatic control of the tower bottom temperature and automatic control of the tower bottom liquid level after blowdown. The blowdown process automatically calculates the initial point of the high-boiling-point tower bottom temperature after blowdown and automatically switches to control the tower bottom liquid level after blowdown, improving the tower's operating efficiency.

[0071] This method effectively achieves automatic blowdown of the high-boiling-point tower. During the automatic blowdown process, it ensures the balance of various indicators of the high-boiling-point tower, keeping all parameters within a reasonable range and guaranteeing the production safety of the high-boiling-point tower. The realization of automatic blowdown control enables semi-unmanned operation of the high-boiling-point tower, improves the intelligence of production, reduces the labor intensity of workers, and ensures product quality.

[0072] This application also provides a coordinated control system for the temperature and level parameters of the reboiler in a VCM distillation high-boiling column. The system includes:

[0073] The high boiling point tower drain valve control module is used to determine whether the drain valve is open or closed by acquiring the high boiling point tower bottom liquid level and tower bottom temperature values, and to control the opening degree of the drain valve according to the rate of change of the high boiling point tower bottom liquid level and the rate of change of the tower bottom temperature during the high boiling point tower drain process.

[0074] The hot water regulating valve control module for high boiling tower is used to control the high boiling tower bottom temperature as the target control point during the high boiling tower blowdown process and the high boiling tower bottom liquid level as the target control point during the non-high boiling tower blowdown process.

[0075] The condenser regulating valve control module is used to control the pressure of the high-boiling tower condenser through a single-loop condenser regulating valve at the top of the high-boiling tower.

[0076] The reflux regulating valve control module is used to control the reflux tank level by using the high-boiling tower top temperature as feedforward for the reflux tank level.

[0077] The VCM distillation high-boiling-point column reboiler temperature and level parameter coordination control system provided in this application embodiment is used to implement the aforementioned VCM distillation high-boiling-point column reboiler temperature and level parameter coordination control method. Specific limitations of the VCM distillation high-boiling-point column reboiler temperature and level parameter coordination control system can be found in the above-described limitations of the VCM distillation high-boiling-point column reboiler temperature and level parameter coordination control method, and will not be repeated here. Each part of the aforementioned VCM distillation high-boiling-point column reboiler temperature and level parameter coordination control system can be implemented entirely or partially through software, hardware, or a combination thereof. The aforementioned modules can be embedded in or independent of the processor in the device in hardware form, or stored in the device's memory in software form, so that the processor can call and execute the operations corresponding to the above modules.

[0078] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0079] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for coordinated control of reboiler temperature and liquid level parameters in a VCM distillation high-boiling column, characterized in that, The method includes: The high-boiling-point tower drain valve control specifically determines whether to open or close the drain valve by acquiring the high-boiling-point tower bottom liquid level and temperature values, and controls the opening degree of the drain valve based on the rate of change of the high-boiling-point tower bottom liquid level and the rate of change of the tower bottom temperature during the high-boiling-point tower drain process; the high-boiling-point tower hot water regulating valve control specifically uses the feed valve as a feedforward, and uses the high-boiling-point tower bottom temperature as the target control point during the high-boiling-point tower drain process, and uses the high-boiling-point tower bottom liquid level as the target control point during the non-high-boiling-point tower drain process. The pressure of the high-boiling-point tower condenser is controlled by a single-loop condenser control valve at the top of the high-boiling-point tower. The reflux regulating valve is controlled by the liquid level in the reflux tank, and the top temperature of the high-boiling tower is used as the feedforward for the liquid level in the reflux tank. In the control of the high-boiling-point tower drain valve, the opening or closing of the drain valve is determined by acquiring the tower bottom liquid level and tower bottom temperature values, including: When the liquid level in the bottom of the high-boiling tower is higher than the set value and the temperature in the bottom of the tower continues to rise, it is determined that the drain valve needs to be opened. When the liquid level in the bottom of the high-boiling tower is lower than the set value and the temperature in the bottom of the tower is stable, it is determined that the drain valve needs to be closed. The method further includes: Set the minimum and maximum sewage discharge intervals; In the control of hot water regulating valves for high-boiling-point towers, the tower bottom temperature is used as the target control point during high-boiling-point tower blowdown, while the tower bottom liquid level is used as the target control point during non-high-boiling-point tower blowdown. This includes: During the high boiling point tower blowdown process, the goal is to control the tower bottom temperature, and the opening of the hot water regulating valve is dynamically adjusted according to the real-time temperature value. During the non-high boiling tower wastewater discharge process, the goal is to control the liquid level in the high boiling tower bottom. The opening of the hot water regulating valve is dynamically adjusted based on the real-time liquid level value. At the same time, the opening of the feed valve is used as a feedforward signal to predict and control the feed and evaporation rates of the high boiling tower.

2. The method according to claim 1, characterized in that, In the control of the hot water regulating valve of the high-boiling tower, the method further includes: The control point of the tower bottom temperature is dynamically adjusted in real time based on the average temperature over a preset period before the start of the blowdown, the rate of temperature change in the tower bottom after the blowdown, and the process parameter control indicators.

3. The method according to claim 1, characterized in that, In the control of the hot water regulating valve of the high-boiling tower, the method further includes: After the high boiling point tower finishes its blowdown process, the blowdown valve is closed, and after a preset delay, the hot water control switches to control the liquid level in the high boiling point tower bottom.

4. The method according to claim 1, characterized in that, In the control of the reflux regulating valve, the specific control object is the liquid level in the reflux tank, and the top temperature of the high-boiling tower is used as the feedforward for the liquid level control in the reflux tank, including: Using the reflux tank level as the control object, the target value of the reflux tank level is dynamically adjusted based on the real-time monitoring of the high-boiling tower feed rate, evaporation rate, and the high-boiling tower top temperature when the condensation pressure at the top of the tower is stable.

5. The method according to claim 1, characterized in that, The method further includes: The process data of the high boiling tower blowdown valve control, high boiling tower hot water regulating valve control, condensate regulating valve control, and reflux regulating valve control are visualized.

6. A coordinated control system for reboiler temperature and level parameters in a VCM distillation high-boiling column, characterized in that, The system includes: The high-boiling-point tower blowdown valve control module is used to determine whether the blowdown valve is open or closed by acquiring the high-boiling-point tower bottom liquid level and temperature values, and to control the opening degree of the blowdown valve according to the rate of change of the high-boiling-point tower bottom liquid level and the rate of change of the tower bottom temperature during the blowdown process; the high-boiling-point tower hot water regulating valve control module is used to control the high-boiling-point tower by using the feed valve as a feedforward, using the high-boiling-point tower bottom temperature as the target control point during the high-boiling-point tower blowdown process, and using the high-boiling-point tower bottom liquid level as the target control point during the non-high-boiling-point tower blowdown process. The condenser regulating valve control module is used to control the pressure of the high-boiling tower condenser through a single-loop condenser regulating valve at the top of the high-boiling tower. The reflux regulating valve control module is used to control the reflux tank level with the high boiling tower top temperature as the feedforward for the reflux tank level. In the control of the high-boiling-point tower drain valve, the opening or closing of the drain valve is determined by acquiring the tower bottom liquid level and tower bottom temperature values, including: When the liquid level in the bottom of the high-boiling tower is higher than the set value and the temperature in the bottom of the tower continues to rise, it is determined that the drain valve needs to be opened. When the liquid level in the bottom of the high-boiling tower is lower than the set value and the temperature in the bottom of the tower is stable, it is determined that the drain valve needs to be closed. The system also includes: Set the minimum and maximum sewage discharge intervals; In the control of hot water regulating valves for high-boiling-point towers, the tower bottom temperature is used as the target control point during high-boiling-point tower blowdown, while the tower bottom liquid level is used as the target control point during non-high-boiling-point tower blowdown. This includes: During the high boiling point tower blowdown process, the goal is to control the tower bottom temperature, and the opening of the hot water regulating valve is dynamically adjusted according to the real-time temperature value. During the non-high boiling tower wastewater discharge process, the goal is to control the liquid level in the high boiling tower bottom. The opening of the hot water regulating valve is dynamically adjusted based on the real-time liquid level value. At the same time, the opening of the feed valve is used as a feedforward signal to predict and control the feed and evaporation rates of the high boiling tower.

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