Method for detecting content of high-boiling-point solvent in tower top water of rectifying tower

Abstract

The invention provides a method for detecting the content of a high-boiling-point solvent in water at the top of a rectifying tower, which comprises the following steps: when the content of the high-boiling-point solvent in the water at the top of the rectifying tower is detected to be greater than a first preset threshold value, obtaining the temperature at the top of the rectifying tower; if the tower top temperature is higher than a second preset threshold value, acquiring a plurality of rectification parameters; judging whether the plurality of rectification parameters are all located in a plurality of corresponding preset ranges or not; if yes, a plurality of feeding parameters are obtained; judging that at least one feeding parameter exceeds a corresponding preset range; determining a target regulation and control scheme according to a preset reason query list and the at least one feeding parameter; if not, determining at least one abnormal rectification parameter, and determining a target regulation and control scheme according to the reason query list and the at least one rectification parameter; and executing the target regulation and control scheme. According to the invention, the content of the high-boiling-point solvent in the water at the top of the rectifying tower can be accurately and flexibly controlled.

Description

Technical Field

[0001] This application relates to the technical field of automatic control in the rectification process, and particularly relates to a method for detecting the content of high-boiling-point solvents in the water at the top of a rectification column. Background Art

[0002] In the solvent recovery process, rectification is the core technology for separating high-boiling-point solvents (such as DMF, NMP, ethylene glycol, etc.) from water or low-boiling-point impurities. High-boiling-point solvents and water usually form an azeotropic system or a near-azeotropic system, and the separation is difficult. It is necessary to precisely control rectification parameters, such as temperature, reflux ratio, feed load, etc., to achieve efficient separation. In actual production, the content of high-boiling-point solvents in the water at the top of the rectification column is unstable and often exceeds the standard. The excessive content of high-boiling-point solvents in the top product may be accompanied by abnormal tower temperature. The excessive content of high-boiling-point solvents in the water at the top of the column leads to the quality of the recovered rectification product not meeting the production requirements, causing waste of resources and economic losses, and also affecting the normal operation of the subsequent production process.

[0003] The existing detection schemes for the content of high-boiling-point solvents in the water at the top of the rectification column have the following disadvantages: relying only on single-parameter adjustment, unable to cope with the coupling effects of multiple parameters; lacking a coordinated processing mechanism for abnormal conditions such as fluctuations in feed rate and sudden changes in concentration, which easily leads to disorder of the tower internal balance; using fixed threshold control, not dynamically adjusting in combination with the parameter change rate, resulting in problems of adjustment lag or over-adjustment; the water at the top of the column and the abnormal discharge are not effectively recycled, causing waste of resources. Summary of the Invention

[0004] This application provides a method for detecting the content of high-boiling-point solvents in the water at the top of a rectification column. By using the tower internal temperature to assist in determining the situation where the content of high-boiling-point solvents in the water at the top of the column exceeds the standard. When the steam amount of the reboiler, the cooling water flow rate, and the reflux ratio are normal, the excessive concentration of the water at the top of the column can also be caused by the feed rate and the feed concentration. Then, by adjusting the feed rate and the feed concentration, the content of high-boiling-point solvents in the water at the top of the column can be adjusted; when the steam amount of the reboiler, the cooling water flow rate, and the reflux ratio are abnormal, the condensation amount of the top gas phase components is adjusted by adjusting the corresponding values of the abnormal parameters, thereby reducing the concentration of high-boiling-point solvents in the water at the top of the column.

[0005] In a first aspect, the present application provides a method for detecting the content of high-boiling-point solvents in the overhead water of a distillation column. The distillation column purifies the high-boiling-point solvents by distilling the bottom waste liquid. A reboiler is provided at the bottom of the distillation column, and the overhead gas outlet of the distillation column is connected to a condenser and a reflux drum in sequence through a pipeline. Among them, the reboiler is connected to hot steam to heat and distill the bottom waste liquid, and the condenser is connected to cooling water to condense the gas components discharged from the overhead gas outlet of the distillation column to obtain a mixed liquid phase. In the reflux drum, the mixed liquid phase is stratified to form a liquid phase component and the overhead water mainly composed of liquid water. The liquid phase component is refluxed to the top of the distillation column to continue the distillation and purification. The method includes: When it is detected that the content of the high-boiling-point solvent in the overhead water is greater than a first preset threshold, obtain the overhead temperature of the distillation column; If it is detected that the overhead temperature is higher than a second preset threshold, obtain a plurality of distillation parameters, and the plurality of distillation parameters include the overhead reflux flow rate, the cooling water flow rate, and the steam flow rate; Judge whether the parameter values of the plurality of distillation parameters are all within corresponding first preset ranges; If so, obtain a plurality of feed parameters, and the plurality of feed parameters include the waste liquid feed flow rate and the waste liquid feed concentration; and, judge that the parameter values of at least one feed parameter exceed corresponding at least one second preset range; and, determine a target regulation scheme according to a preset cause query list and the parameter values of the at least one feed parameter, and the cause query list is used to represent a plurality of regulation schemes corresponding to abnormal parameter values of the plurality of distillation parameters and the plurality of feed parameters; and, If not, determine at least one distillation parameter with abnormal parameter values, and determine the target regulation scheme according to the cause query list and the parameter values of the at least one distillation parameter; Execute the target regulation scheme, and after the execution is completed, it is detected that the content of the high-boiling-point solvent in the overhead water is less than the first preset threshold.

[0006] In a second aspect, an embodiment of the present application provides an electronic device, including a processor, a memory, and one or more programs. The one or more programs are stored in the memory and are configured to be executed by the processor. The programs include instructions for executing the steps in the first aspect of the embodiments of the present application.

[0007] In a third aspect, an embodiment of the present application provides a computer-readable storage medium, on which a computer program / instructions are stored, and the computer program / instructions are executed by a processor to implement the steps of the method described in the first aspect above.

[0008] It can be seen that in the embodiment of the present application, when it is detected that the content of the high boiling point solvent in the tower top water is greater than the first preset threshold, the tower top temperature of the distillation tower is obtained; if it is detected that the tower top temperature is higher than the second preset threshold, multiple distillation parameters are obtained; it is determined whether the parameter values of multiple distillation parameters are all within the corresponding multiple first preset ranges; if so, multiple feed parameters are obtained; and, it is determined that the parameter value of at least one feed parameter exceeds the corresponding at least one second preset range; and, according to the preset reason query list and the parameter value of at least one feed parameter, the target control scheme is determined; and, if not, at least one distillation parameter with abnormal parameter value is determined, and the target control scheme is determined according to the reason query list and the parameter value of at least one distillation parameter; the target control scheme is executed, and after the execution is completed, it is detected that the content of the high boiling point solvent in the tower top water is less than the first preset threshold. In this way, compared with the existing detection scheme of the content of the high boiling point solvent in the tower top water, the present application breaks through the limitations of the traditional single parameter adjustment, and realizes the precise and flexible control of the content of the high boiling point solvent in the tower top water of the distillation tower through the linkage analysis of the tower top temperature, distillation parameters and feed parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0010] Figure 1 It is a structural schematic diagram of a detection system for the content of high-boiling-point solvent in water at the top of a distillation tower provided in an embodiment of the present application; Figure 2 This is a schematic diagram of the system architecture of a system for detecting the content of high-boiling-point solvents in water at the top of a distillation tower provided in an embodiment of the present application; Figure 3 is a structural schematic diagram of a control module provided in an embodiment of the present application; Figure 4 This is a process flow chart of top water provided in an embodiment of the present application; Figure 5 It is a structural schematic diagram of an electronic device provided in an embodiment of the present application; Figure 6 It is a flow chart of the steps of a method for detecting the content of high-boiling-point solvent in water at the top of a distillation tower provided in an embodiment of the present application; Figure 7 It is a schematic diagram of a process of a tower top temperature reduction control scheme provided in an embodiment of the present application; Figure 8It is a schematic diagram of the overall process of a method for detecting the content of high-boiling solvents in the overhead water of a distillation column provided by an embodiment of the present application; Figure 9 It is a schematic diagram of the functional modules of a device for detecting the content of high-boiling solvents in the overhead water of a distillation column provided by an embodiment of the present application. Detailed implementation manners

[0011] In order to enable those skilled in the art to better understand the solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0012] The terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices.

[0013] Referring to "embodiment" herein means that a specific feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The phrase appears in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0014] The "and / or" in the embodiments of the present application describes the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone; A and B exist simultaneously; B exists alone. Among them, A and B can be singular or plural.

[0015] In the embodiments of the present application, the symbol " / " can represent that the front and rear associated objects are an "or" relationship. In addition, the symbol " / " can also represent a division sign, that is, perform a division operation. For example, A / B can represent A divided by B.

[0016] The "at least one (piece)" or its similar expression in the embodiments of the present application refers to any combination of these items, including any combination of a single item (piece) or multiple items (pieces), meaning one or more, and multiple means two or more. For example, at least one (piece) of a, b, or c can represent the following seven cases: a, b, c, a and b, a and c, b and c, a, b, and c. Each of a, b, and c can be an element or a set containing one or more elements.

[0017] In the embodiments of the present application, "equal to" can be used in combination with "greater than", applicable to the technical solutions adopted when it is greater than, and can also be used in combination with "less than", applicable to the technical solutions adopted when it is less than. When "equal to" is used in combination with "greater than", it is not used in combination with "less than"; when "equal to" is used in combination with "less than", it is not used in combination with "greater than".

[0018] The existing detection schemes for the content of high-boiling solvents in the overhead water of a distillation column have the following disadvantages: relying only on the adjustment of a single parameter, unable to cope with the coupled influence of multiple parameters; lacking a collaborative processing mechanism for abnormal conditions such as fluctuations in the feed rate and sudden changes in concentration, which easily leads to disorder in the tower equilibrium; adopting fixed threshold control, without dynamically adjusting in combination with the parameter change rate, resulting in problems of adjustment lag or overshoot; the overhead water and abnormal discharge are not effectively recycled, causing waste of resources.

[0019] In view of the above problems, the embodiments of the present application provide a method for detecting the content of high-boiling solvents in the overhead water of a distillation column. The embodiments of the present application will be introduced in detail below with reference to the accompanying drawings.

[0020] Please refer to Figure 1 , FIG. 1 is a schematic structural diagram of a detection system for the content of high-boiling solvents in the overhead water of a distillation column provided by the embodiments of the present application. As shown in FIG. 1, Figure 1 the detection system for the content of high-boiling solvents in the overhead water of the distillation column includes a control module 110 and a distillation column 120.

[0021] Among them, the control module 110 is the core control unit of the entire detection system, responsible for receiving, processing, and analyzing relevant data from the distillation column 120. It can regulate the detection process of the content of high-boiling solvents in the overhead water of the distillation column 120 according to preset algorithms, thresholds, etc. For example, when it is detected that the content of high-boiling solvents exceeds the set range, the control module 110 can automatically issue an instruction to adjust the operating parameters (such as reflux ratio, heating amount, etc.) of the distillation column 120 to restore the normal distillation process.

[0022] The rectification column 120 is a key device for realizing the separation of mixtures. Through multiple partial vaporizations and partial condensations, a distillate rich in low-boiling components (including overhead water) is produced at the top of the column, and a bottoms residue rich in high-boiling components is produced at the bottom of the column. In this detection system, the rectification column 120 is the source of the object for detecting the content of high-boiling solvents. The overhead water is used as a sample, and the content of high-boiling solvents in it is the parameter to be detected. The rectification column 120 feeds back data related to the overhead water to the control module 110 (such as through a sensor installed on the outlet pipe of the overhead water), and at the same time receives the regulation instructions issued by the control module 110 to adjust its own operating parameters (such as changing the reflux ratio, steam input amount, etc.) to maintain the stability of the separation process in the rectification column 120 and the content of high-boiling solvents in the overhead water within an appropriate range.

[0023] Specifically, please refer to Figure 2 , Figure 2 which is a schematic diagram of the system architecture of a detection system for the content of high-boiling solvents in the overhead water of a rectification column provided by an embodiment of the present application. As Figure 2 shown, the detection system for the content of high-boiling solvents in the overhead water of a rectification column includes a rectification column 120 and a control module 110. Among them, the rectification column 120 includes a monitoring module 121 and a rectification module 122. The monitoring module 121 includes a temperature sensor 1211, a rectification parameter monitoring device 1212, and a feed parameter monitoring device 1213. The rectification module 122 includes a rectification component 1221 and a valve component 1222.

[0024] Among them, the temperature sensor 1211 is used to monitor the temperature of key parts (such as the top and bottom of the column) in the rectification column 120 in real time; the rectification parameter monitoring device 1212 is used to monitor rectification-related parameters such as pressure, reflux ratio, and plate efficiency. For example, it may include: a pressure sensor, a flow monitoring component, a liquid level monitoring component, a composition monitoring component, etc.; the feed parameter monitoring device 1213 is used to monitor parameters such as the flow rate, temperature, concentration, and pressure of the feed. For example, it may include: an electromagnetic flowmeter, a vortex street flowmeter, a mass flowmeter, etc., a pressure transmitter, a near-infrared spectrometer, a gas chromatograph, a density meter, a refractometer, etc.

[0025] Among them, the rectification component 1221 includes a reboiler, a condenser, a reflux drum, and a column body. The valve component 1222 includes a steam valve, a cold water valve, a reflux valve, a feed valve, and a discharge valve. Among them, the reboiler is connected to hot steam through the steam valve to heat and rectify the bottom waste liquid. The condenser is connected to cooling water through the cold water valve to condense the gas-phase components discharged from the gas-phase outlet at the top of the column to obtain a mixed liquid phase. The mixed liquid phase in the reflux drum is stratified to form a liquid-phase component and overhead water formed by liquid water. The liquid-phase component is refluxed to the top of the rectification column 120 through the reflux valve to continue the rectification and purification.

[0026] Furthermore, for the specific functions of the control module 110, please refer toFigure 3 , Figure 3 is a schematic structural diagram of a control module provided by an embodiment of the present application. As Figure 3 shown, the control module 110 includes a detection unit 310 and a processing unit 320.

[0027] Among them, the detection unit 310 is used to receive real-time data fed back by a plurality of monitoring devices in the rectification column, including parameters such as temperature, pressure, flow rate, liquid level, and component concentration. These data are the basis for understanding the operating state of the rectification column and provide a basis for subsequent analysis and decision-making.

[0028] Among them, the processing unit 320 is used to deeply analyze and process the data transmitted by the detection unit 310. It calculates, compares, and judges the data according to preset algorithms, models, and control strategies, and evaluates whether the operating state of the rectification column is normal. If an abnormality is found (such as a parameter exceeding the set threshold), corresponding control instructions are generated to adjust the operating parameters of the rectification column to achieve optimized control of the rectification process. At the same time, the processing results can also be fed back to the operator or other monitoring systems.

[0029] It can be seen that in this embodiment, the entire control module 110 realizes real-time monitoring and precise control of the operating state of the rectification column through the collaborative work of the detection unit 310 and the processing unit 320, ensuring the stable and efficient operation of the rectification process.

[0030] Next, in combination with Figure 4 a process for generating overhead water provided by an embodiment of the present application will be described. Figure 4 is a process flow diagram of a process for generating overhead water provided by an embodiment of the present application. As Figure 4 shown, the rectification column 120 rectifies the bottom waste liquid to achieve purification of the high-boiling solvent, and generates overhead water during the rectification process.

[0031] Among them, the reboiler 42 is connected to the steam pipeline 422 through the steam valve 421. The steam valve 421 is used to regulate the steam flow rate of the hot steam. The condenser 43 is connected to the cold water pipeline 432 through the cold water valve 431. The cold water valve 431 is used to regulate the cooling water flow rate of the cooling water. The reflux drum 44 is connected to the reflux valve 441. The reflux valve 441 is used to regulate the reflux amount of the liquid phase component returning to the top of the column. The liquid phase component is the high-boiling solvent purified after this rectification, and the reflux drum 44 is also used to output the overhead water through the pipeline 442.

[0032] Further, the tower body of the rectification column 120 is also provided with a feed inlet 45 and a discharge outlet 46. The feed inlet 45 is connected to a feed valve 451, and the feed valve 451 is used to regulate the feed rate of the waste liquid material input into the tower. The discharge outlet 46 is connected to a discharge valve 461. The discharge valve 461 is used to output the high-purity product corresponding to the high-boiling solvent after multiple refluxes and purifications, and the discharge valve 461 is also used to control the discharge rate of the waste liquid material in the tower under abnormal conditions. In addition, a temperature sensor is provided at the top of the rectification column 120, represented by the letter "T". The temperature sensor is used to monitor the temperature at the top of the tower in real time.

[0033] It can be understood that based on the above connection structure of the rectification column 120, the technological process of the water at the top of the tower can be clarified as follows: The waste liquid is placed in the tower kettle of the rectification column 120 through the feed inlet 45. The tower kettle is connected to the reboiler 42 through a liquid-phase pipeline to transport the waste liquid into the reboiler 42. The reboiler 42 is connected to hot steam to heat and rectify the waste liquid to obtain a gas-phase component, and the reboiler 42 is connected to the rectification column 120 through a gas-phase pipeline to transport the gas-phase component back into the rectification column 120. The gas-phase component is discharged from the gas-phase outlet at the top of the tower to the condenser 43. The condenser 43 is connected to cooling water to condense the gas-phase component to obtain a mixed liquid phase, and the mixed liquid phase is transported to the reflux drum 44. The mixed liquid phase is separated into a liquid-phase component and the water at the top of the tower in the reflux drum 44. Then, the liquid-phase component is refluxed to the top of the rectification column 120 through the reflux valve 441, and the water at the top of the tower is output through the pipeline 442.

[0034] This application also provides an electronic device 50, as Figure 5 shown, Figure 5 is a schematic structural diagram of an electronic device provided by an embodiment of this application. The electronic device 50 may include one or more of the following components: a memory, a processor, a communication bus, a communication interface, and one or more programs. The one or more programs are stored in the memory and are configured to be executed by the processor. The one or more programs include instructions for executing any step in the following method embodiments. Specifically, in implementation, the processor is used to execute any step in the following method embodiments, and when performing data transmission such as sending, the communication interface can be selectively called to complete the corresponding operation.

[0035] Next, in combination with Figure 6 a detection method for the content of high-boiling solvents in the water at the top of the rectification column provided by an embodiment of this application will be described. Figure 6 is a step flowchart of a detection method for the content of high-boiling solvents in the water at the top of the rectification column provided by an embodiment of this application, which specifically includes the following steps: Step S610, when it is detected that the content of the high-boiling solvent in the water at the top of the tower is greater than a first preset threshold, obtain the temperature at the top of the rectification column.

[0036] Among them, a temperature sensor is provided at the top of the distillation column, and the temperature at the top of the column can be detected in real time based on the temperature sensor.

[0037] It can be understood that the high-boiling solvent in the top water is essentially the result of incomplete distillation separation, and the temperature at the top of the column is the core parameter reflecting the gas-liquid equilibrium in the distillation process. An abnormal temperature is often directly related to the separation efficiency. For example, too high a temperature may cause high-boiling components to not be fully condensed and escape with the gas phase, entering the top water.

[0038] Step S620: If it is detected that the temperature at the top of the column is higher than the second preset threshold, then obtain multiple distillation parameters.

[0039] Among them, the multiple distillation parameters include the reflux flow rate at the top of the column, the cooling water flow rate, and the steam flow rate.

[0040] Among them, the distillation column is provided with multiple sensors, which are respectively used to obtain the reflux flow rate at the top of the column, the cooling water flow rate, and the steam flow rate.

[0041] Specifically, it is necessary to synchronously collect the three parameters to avoid data correlation distortion caused by time differences (for example, it takes 30 seconds for the steam flow rate adjustment to be reflected in the temperature at the top of the column), and it is required that the accuracy of each parameter sensor be matched (such as temperature ±0.5°C, flow rate ±1%) to avoid misjudgment caused by measurement errors.

[0042] It can be understood that the reflux flow rate directly affects the gas-liquid contact efficiency and the separation ability of the rectifying section in the column. When the reflux flow rate is insufficient, high-boiling solvents are easily entrained in the light components (such as water) at the top of the column, resulting in an increase in temperature; when the cooling water flow rate is small, if the cooling is insufficient, the gas-phase components cannot be fully condensed, and some high-boiling solvents enter the top water in a gaseous form, while causing the temperature at the top of the column to remain high; too large a steam volume may cause the upward gas velocity in the column to be too fast, resulting in entrainment of mists (high-boiling liquid droplets are carried to the top of the column) and increasing the bottom heating of the column, resulting in an overall increase in temperature.

[0043] Furthermore, if the temperature does not exceed the second preset threshold, a normal temperature at the top of the column indicates that the gas-liquid equilibrium in the distillation column is basically maintained, and it may be necessary to check other non-temperature-dominated factors (such as equipment failures, parameter matching imbalances, etc.).

[0044] Specifically, equipment failures may include: (1) Reflux system failures: Reflux pump failures such as impeller wear and motor failures can cause unstable or insufficient reflux flow, making it impossible to fully wash the high-boiling solvents in the overhead steam of the tower, resulting in their discharge with water. The reflux instrument malfunctions and cannot accurately measure and control the reflux flow, disrupting the gas-liquid equilibrium in the distillation column and deteriorating the separation effect of high-boiling solvents. (2) Poor condenser performance: Condenser fouling reduces the heat transfer efficiency, preventing the overhead steam from being fully condensed. Some high-boiling solvent vapors are mixed into the overhead water without being liquefied. Leakage or blockage in the cooling water pipeline leads to insufficient or uneven distribution of cooling water, affecting the condensation effect and causing fluctuations in the content of high-boiling solvents in the overhead water. (3) Damage to internals in the tower: Deformation, blockage of trays or damage to packing in the tower can disrupt the gas-liquid mass transfer process in the tower, preventing high-boiling solvents from being fully separated in the tower and increasing the content of high-boiling solvents in the overhead water. At the same time, damage to the internals in the tower may also lead to uneven gas-liquid distribution, further deteriorating the distillation effect.

[0045] It should be noted that the embodiments of the present application only give examples of some common hardware equipment failures that cause abnormal increase in the overhead temperature of the distillation column, and do not limit other possible failure situations. Problems in terms of equipment failures need to be determined by means of regular manual inspections.

[0046] It can be seen that in this embodiment, through temperature anomaly triggering and multi-parameter collaborative analysis, the fault diagnosis is deepened from a single index to multi-dimensional parameter linkage. The physical correlation between parameters is used for fault diagnosis, providing a scientific basis for subsequent precise regulation. Through data cross-validation, the root cause of the temperature anomaly is quickly locked, avoiding system oscillations caused by blind adjustment.

[0047] Step S630, determine whether the parameter values of multiple distillation parameters are all within the corresponding multiple first preset ranges.

[0048] Among them, the preset first reflux flow range corresponding to the overhead reflux flow, the preset first cooling water flow range corresponding to the cooling water flow, and the preset first steam flow range corresponding to the steam flow.

[0049] It can be understood that after obtaining distillation parameters such as reflux flow, cooling water flow, and steam flow, by comparing the parameter values with the corresponding preset ranges, it is determined whether the parameters are in normal operating conditions. If all parameters are within the preset ranges, it indicates that there are no direct abnormalities in the distillation operation parameters, and the problem may stem from the feed end or hidden equipment failures; if at least one parameter exceeds the range, the parameter abnormality source is directly located and the corresponding operation is adjusted preferentially.

[0050] Step S640: If so, obtain multiple feed parameters; and, determine that the parameter values of at least one feed parameter exceed the corresponding at least one second preset range; and, determine the target regulation scheme according to the preset cause query list and the parameter values of at least one feed parameter.

[0051] Among them, the cause query list is used to represent multiple regulation schemes corresponding to abnormal parameter values of multiple rectification parameters and multiple feed parameters. The cause query list can be constructed and optimized based on process design documents, expert experience, historical fault records, through machine learning training, abnormal case iteration, and integrated AI models.

[0052] Among them, the second preset range includes the second preset feed range corresponding to the waste liquid feed rate and the second preset feed concentration range corresponding to the waste liquid feed concentration.

[0053] In a possible embodiment, determining the target regulation scheme according to the preset cause query list and the parameter values of at least one feed parameter includes: if it is determined that the waste liquid feed rate is greater than the maximum threshold of the corresponding second preset feed range, then determine the target regulation scheme according to the cause query list as reducing the opening degree of the feed valve to reduce the feed rate of the waste liquid material, and increasing the opening degree of the discharge valve to discharge part of the waste liquid material in the tower through the discharge port and participate in the rectification process again; if it is determined that the waste liquid feed concentration is greater than the maximum threshold of the corresponding second preset feed concentration range, then determine the target regulation scheme according to the cause query list as increasing the opening degree of the reflux valve to increase the reflux amount at the top of the tower, thereby improving the rectification efficiency in the tower; and, increasing the opening degree of the cold water valve to increase the cooling water flow rate, thereby ensuring the full condensation of the gas phase components and reducing the content of the high-boiling solvent in the water at the top of the tower.

[0054] Among them, when it is detected that the waste liquid feed rate exceeds the upper limit of the second preset range, through the coordination of the "inlet - outlet" double valves, the material balance in the tower can be quickly restored.

[0055] Among them, when the concentration of the high-boiling solvent in the feed exceeds the preset upper limit, increasing the opening degree of the reflux valve makes the reflux amount increase and the separation ability of the rectification section improve. However, it is necessary to synchronously increase the condensation amount to avoid the increase of the temperature at the top of the tower. Furthermore, increase the opening degree of the cold water valve to increase the cooling water flow rate, breaking through the limitation of traditional "single parameter regulation" and coping with concentration fluctuations through the coordination of two parameters.

[0056] In a possible embodiment, the method further includes: if it is determined that the waste liquid feed rate is greater than the maximum threshold of the corresponding second preset feed range and the waste liquid feed concentration is greater than the maximum threshold of the corresponding second preset feed concentration range, then according to the cause query list, determine that the target regulation scheme is to reduce the opening degree of the feed valve to decrease the feed rate of the waste liquid material, and increase the opening degree of the discharge valve to discharge a part of the waste liquid material in the tower through the discharge port and participate in the rectification process again; and increase the opening degree of the reflux valve to increase the reflux amount at the top of the tower, thereby improving the rectification efficiency in the tower; and increase the opening degree of the cold water valve to increase the cooling water flow rate, thereby ensuring sufficient condensation of the gas-phase components and reducing the content of the high-boiling solvent in the water at the top of the tower.

[0057] Among them, the applicable scenarios for simultaneously executing the independent regulation schemes corresponding to two parameters given in the above example are: the two anomalies do not form a strong coupling effect (such as a relatively high redundancy in the processing capacity of the tower equipment, or a relatively small excess amplitude of the feed rate and concentration); and the cause query list clearly allows the parallel execution of regulation measures for different parameters (such as the reflux valve, feed valve, and cold water valve can be adjusted simultaneously).

[0058] In a possible embodiment, the method further includes: if it is determined that the waste liquid feed rate is greater than the maximum threshold of the corresponding second preset feed range and the waste liquid feed concentration is greater than the maximum threshold of the corresponding second preset feed concentration range, then determine the parameter priority corresponding to the waste liquid feed rate and the waste liquid feed concentration; determine the feed parameter with the larger parameter priority; and query and determine the target regulation scheme corresponding to the feed parameter with the larger parameter priority according to the cause query list.

[0059] Among them, the applicable scenarios for executing a single regulation scheme according to the priority given in the above example are: there is a causal relationship or coupling risk between the two anomalies (such as an excessive feed rate being the main cause of the concentration detection deviation); and the cause query list defines the priority order of parameter anomalies (such as "feed rate takes precedence over feed concentration").

[0060] Exemplarily, if it is determined that the excess amplitude of the feed rate is greater than the excess amplitude of the concentration, the regulation scheme for "excessive feed rate" is preferentially executed, or if the excessive concentration may directly lead to unqualified product quality (such as the critical value of the high-boiling solvent content), the scheme for "excessive concentration" is preferentially executed.

[0061] In a possible embodiment, the method further includes: if it is determined that the waste liquid feed rate is greater than the maximum threshold of the corresponding second preset feed range and the waste liquid feed concentration is greater than the maximum threshold of the corresponding second preset feed concentration range, then determine the target regulation scheme corresponding to the simultaneous anomalies of the waste liquid feed rate and the waste liquid feed concentration according to the cause query list.

[0062] Among them, the applicable scenarios for the trigger composite regulation scheme given in the above examples are as follows: the probability of two anomalies occurring simultaneously is relatively high, or there are significant risks in parallel regulation (for example, large tower equipment needs to avoid sudden changes in load); and, in the cause query list, exclusive schemes for double-parameter anomalies are predefined, and these exclusive schemes are not simple superpositions of the original rules.

[0063] Exemplarily, when the waste liquid feed rate and the waste liquid feed concentration are simultaneously abnormal, the corresponding target regulation scheme can be: reducing the opening degree of the feed valve to 70% of the original opening degree, increasing the opening degree of the reflux valve to 120% of the original opening degree, and simultaneously increasing the opening degree of the cold water valve by 15%. After a 5-minute delay, decide whether to increase the opening degree of the discharge valve according to the tower kettle liquid level situation (to avoid liquid level fluctuations caused by instantaneous discharging).

[0064] It should be clear that the cause query list usually contains at least independent regulation schemes for single-parameter anomalies. If complex working conditions need to be processed, the list can be extended to include composite regulation schemes for double-parameter or multi-parameter combinations.

[0065] It can be seen that in this embodiment, by real-time monitoring parameters such as the feed rate and feed concentration and comparing them with the preset ranges, using the cause query list constructed based on process experience and machine learning, independent regulation strategies are provided for single-parameter anomalies, and parallel execution, priority selection, or predefined composite schemes are supported for double-parameter simultaneous anomalies, realizing precise diagnosis and intelligent regulation under complex working conditions in the rectification process, improving system stability and separation efficiency, and reducing the cost of manual intervention.

[0066] Step S650, if not, then determine at least one rectification parameter with an abnormal parameter value, and determine the target regulation scheme according to the cause query list and the parameter values of the at least one rectification parameter.

[0067] It can be understood that when rectification parameters (reflux rate, cooling water flow rate, steam flow rate) are abnormal, the root cause of the problem can be quickly located through the cause query list and targeted regulation can be implemented.

[0068] In a possible embodiment, determining at least one rectification parameter with an abnormal parameter value includes: determining a preset first reflux rate range corresponding to the top reflux rate, a preset first cooling water flow rate range corresponding to the cooling water flow rate, and a preset first steam flow rate range corresponding to the steam flow rate; if it is determined that the top reflux rate is less than the minimum threshold of the first reflux rate range, then determine the top reflux rate as the abnormal rectification parameter; if it is determined that the cooling water flow rate is less than the minimum threshold of the first cooling water flow rate range, then determine the cooling water flow rate as the abnormal rectification parameter; if it is determined that the steam flow rate is greater than the maximum threshold of the first steam flow rate range, then determine the steam flow rate as the abnormal rectification parameter.

[0069] Among them, the reflux flow range is usually 1.2 - 1.5 times the minimum reflux ratio (for example, the designed value is 500 - 700 L / h), and the lower limit value needs to ensure the continuity of the liquid film on the tray.

[0070] Among them, the cooling water flow range is usually calculated according to the gas phase load at the top of the tower (for example, Qc = 8 - 12 m³ / h). The lower limit needs to ensure that the condensation temperature is lower than the solvent dew point. The dew point refers to the temperature at which the gas phase components are cooled to start the appearance of liquid phase condensation under a fixed pressure. For example, for the mixed gas phase of a high-boiling solvent and water, when the temperature drops below the dew point, the solvent will start to condense. If the cooling water flow is insufficient and the condensation temperature is higher than the dew point, part of the solvent will enter the top water in gaseous form, resulting in an excessive content.

[0071] Among them, the steam flow range is calculated based on the bottom vaporization demand (for example, Qs = 300 - 400 kg / h). The upper limit needs to avoid entrainment of liquid droplets (F factor ≤ 0.8 Pa^0.5).

[0072] It can be understood that only the lower limit is set for the reflux flow and the cooling water flow to prevent insufficiency, and only the upper limit is set for the steam flow to prevent overload, which is in line with the characteristics of the distillation process.

[0073] In a possible embodiment, a target regulation scheme is determined according to the cause query list and the parameter values of at least one distillation parameter, including: if the at least one distillation parameter is the reflux flow at the top of the tower, then according to the cause query list, the target regulation scheme is determined to increase the opening degree of the reflux valve to increase the reflux flow at the top of the tower, and then improve the distillation efficiency in the tower by reducing the temperature at the top of the tower; if the at least one distillation parameter is the cooling water flow, then according to the cause query list, the target regulation scheme is determined to increase the opening degree of the cold water valve to increase the cooling water flow, and then ensure that the gas phase components are fully condensed, so that the content of the high-boiling solvent in the top water is reduced; if the at least one distillation parameter is the steam flow, then according to the cause query list, the target regulation scheme is determined to reduce the opening degree of the steam valve to reduce the steam flow, and then stabilize the gas-liquid balance in the tower and avoid the rapid rise of water vapor in the tower resulting in insufficient condensation of the gas phase components and their dissolution in the top water.

[0074] Among them, if the reflux valve is fully opened and still cannot meet the standard, the standby pump switching logic is automatically triggered; and, a lower limit of the cooling water temperature is set (for example, > 5 °C) to prevent damage to the condenser caused by freezing; and, if the sudden drop in the steam flow may affect the liquid holdup at the bottom of the tower, the bottom discharge amount can be synchronously reduced, such as reducing the bottom discharge amount by 10%.

[0075] Further, if there are two or more abnormal rectification parameters, the scheme for determining the target regulation when two discharge parameters are abnormal simultaneously as given in the foregoing examples can be referred to, and the regulation is carried out by parallel execution, priority selection or predefined composite scheme.

[0076] It can be seen that in this embodiment, by presetting a reasonable range of rectification parameters, comparing the parameter values with the thresholds in real time, accurately identifying abnormal parameters, and executing targeted regulation schemes based on the cause query list, the rapid positioning and intelligent regulation of abnormal rectification parameters are realized, the gas-liquid balance and separation efficiency in the tower are ensured, and the system stability and safety are improved.

[0077] Step S660, execute the target regulation scheme, and after the execution is completed, it is detected that the content of the high-boiling solvent in the overhead water is less than the first preset threshold.

[0078] Among them, the content of the high-boiling solvent in the overhead water can be monitored in real time by an on-line infrared analyzer (such as updating the data every 2 minutes) to ensure timely feedback of the regulation effect.

[0079] It should be clear that the present application does not limit the execution subject of the target regulation scheme. The whole process of detection and execution can be fully automated based on an automated system, or the target regulation scheme can be output on an interactive interface to prompt the user to execute the target regulation scheme.

[0080] In a possible embodiment, after executing the target regulation scheme, the method further includes: if it is detected that the concentration of the waste liquid feed drops, then reduce the opening degree of the reflux valve to reduce the overhead reflux flow rate, and reduce the opening degree of the cold water valve to reduce the cooling water flow rate.

[0081] It can be understood that after executing the target regulation scheme, by monitoring the change of the feed concentration in real time and dynamically adjusting the reflux and cooling parameters, the energy consumption waste caused by "over-regulation" is avoided, and the dynamic balance of "separation efficiency and energy consumption control" is realized.

[0082] In a possible embodiment, after executing the target regulation scheme, the method further includes: determining the lowest temperature threshold corresponding to the overhead temperature, where the lowest temperature threshold is a preset lowest temperature value that the overhead can adapt to when the rectification column can maintain normal operation; detecting that the overhead temperature drops; adjusting the parameter values of the at least one rectification parameter according to the dropping speed of the overhead temperature to prevent the overhead temperature from dropping below the lowest temperature threshold.

[0083] Among them, by monitoring the change speed of the overhead temperature in real time and dynamically adjusting the rectification parameters (reflux ratio, cooling water flow rate, etc.), the low-temperature fluctuation caused by over-regulation is prevented, the rectification column is ensured to operate within a safe temperature range, and malignant working conditions such as flooding and entrainment of liquid droplets are avoided.

[0084] It can be seen that in this embodiment, the situation where the content of the high-boiling solvent in the overhead water exceeds the standard is determined by assisting with the tower temperature. When the reboiler steam flow rate, cooling water flow rate, and reflux flow rate are normal, the overhead water concentration can also exceed the standard due to the feed rate and feed concentration. Furthermore, the content of the high-boiling solvent in the overhead water is adjusted by adjusting the feed rate and feed concentration. When the reboiler steam flow rate, cooling water flow rate, and reflux flow rate are abnormal, the condensation amount of the overhead gas phase components is adjusted by adjusting the corresponding values of the abnormal parameters, thereby reducing the concentration of the high-boiling solvent in the overhead water, breaking through the limitations of traditional single-parameter regulation, and achieving precise and flexible control of the content of the high-boiling solvent in the overhead water of the distillation column through the linkage analysis of the overhead temperature, distillation parameters, and feed parameters.

[0085] Please refer to Figure 7 , Figure 7 which is a schematic flow chart of a control scheme for the decrease in overhead temperature provided by an embodiment of the present application. Among them, in terms of adjusting the parameter values of the at least one distillation parameter according to the decrease rate of the overhead temperature, the above method may further include the following steps: Step S710, it is detected that the overhead temperature decreases.

[0086] Specifically, the overhead temperature is monitored in real time through a temperature sensor, and it is triggered when the temperature shows a downward trend for a continuous plurality (such as 3) of sampling periods (such as once every 30 seconds) and the cumulative decrease reaches a preset amplitude (such as > 0.5 °C).

[0087] Step S720, determine the lowest temperature threshold corresponding to the overhead temperature.

[0088] Among them, the lowest temperature threshold is the lowest temperature value that the overhead can adapt to when the distillation column can maintain normal operation as preset. The lowest temperature threshold can be calculated based on the material properties (such as 65 °C for the methanol-water system) and dynamically adjusted according to the feed composition (such as increasing by 2 °C when the high-boiling component increases).

[0089] Step S730, determine the target speed according to the decrease rate of the overhead temperature.

[0090] Among them, the target speed is the "safe adjustment rate" calculated based on the current decrease rate of the overhead temperature and used to guide the adjustment of the distillation parameters. It is not a fixed value but a parameter that is dynamically adjusted with the temperature change. In essence, it converts the temperature change rate into the execution basis for parameter adjustment.

[0091] It is understandable that when the top tower temperature is too high and the parameter values of the rectification parameters are abnormal, adjustments have been made to multiple rectification parameters based on the target control scheme. Specifically, by adjusting the corresponding valve openings. If the valve openings are not restored or adjusted after detecting a decrease in the top tower temperature, it will lead to abnormal operation of the rectification tower. Therefore, it is necessary to adjust the rectification parameters (top tower reflux flow rate, cooling water flow rate, steam flow rate) based on the rate of decrease of the top tower temperature.

[0092] Exemplarily, when the top tower temperature decreases at a low speed (e.g., < 1 °C / min), the target speed = the rate of decrease × 0.8 (allowing slower adjustment to avoid excessive intervention); when the top tower temperature decreases at a high speed (e.g., > 1 °C / min), the target speed = a fixed safety upper limit (e.g., 1 °C / min) to forcibly suppress the speed to prevent runaway. It should be clear that the present application does not limit the relationship between the target speed and the rate of decrease of the top tower temperature. The calculation method of the target speed includes but is not limited to one of the above examples.

[0093] Step S740, whether at least one of the rectification parameters with abnormal parameter values is the top tower reflux flow rate.

[0094] Specifically, if so, execute step S741; if not, execute step S750.

[0095] Step S741, reduce the opening of the reflux valve so that the top tower reflux flow rate decreases at the target speed.

[0096] Among them, the relationship between the target speed and the reduction rate of the reflux flow rate can be obtained from historical data. For example, when the target speed is 0.6 °C / min, the corresponding reduction rate of the reflux flow rate is 0.3 L / min.

[0097] Furthermore, the opening of the reflux valve can be determined based on the linear relationship, mapping relationship or large model between the reduction rate of the reflux flow rate and the opening of the reflux valve, thereby realizing the adjustment of the opening of the reflux valve.

[0098] Step S750, whether at least one of the rectification parameters with abnormal parameter values is the cooling water flow rate.

[0099] Specifically, if so, execute step S751; if not, execute step S752.

[0100] Step S751, reduce the opening of the cold water valve so that the cooling water flow rate decreases at the target speed.

[0101] Among them, the relationship between the target speed and the reduction rate of the cooling water flow rate can be obtained from historical data. For example, when the target speed is 0.6 °C / min, the corresponding reduction rate of the cooling water flow rate is 0.5 L / min.

[0102] Further, the opening degree of the cold water valve can be determined based on the linear relationship, mapping relationship, or large model between the cooling water flow rate reduction rate and the cold water valve opening degree, and then the opening degree of the cold water valve can be adjusted accordingly.

[0103] Step S752: Increase the opening degree of the steam valve so that the steam flow rate increases at a target speed.

[0104] Among them, the relationship between the target speed and the steam flow rate reduction rate can be obtained from historical data. For example, the target speed is 0.6 °C / min, corresponding to a steam flow rate reduction rate of 0.45 L / min.

[0105] Further, the opening degree of the steam valve can be determined based on the linear relationship, mapping relationship, or large model between the steam flow rate reduction rate and the steam valve opening degree, and then the opening degree of the steam valve can be adjusted accordingly.

[0106] Step S760: It is detected that the top tower temperature has not dropped below the minimum temperature threshold.

[0107] It can be understood that the top tower temperature being lower than the minimum temperature threshold may lead to: a sudden increase in the liquid phase load of the top tower condenser, triggering flooding; a decrease in tray efficiency, and the entrainment of heavy components with the gas phase; an increase in the viscosity of the condensate, causing a risk of pipeline blockage. Therefore, it is necessary to continuously detect the top tower temperature and timely adjust the opening degree of the valves corresponding to at least one distillation parameter to ensure that the top tower temperature does not drop below the minimum temperature threshold.

[0108] It can be seen that in this embodiment, through the closed-loop control of real-time monitoring of the temperature change trend, dynamic calculation of the threshold, hierarchical adjustment of parameters, and safety verification, the top tower temperature drop rate is converted into a quantifiable valve adjustment instruction, realizing the coordinated optimization of distillation parameters (reflux, cooling, steam), effectively preventing the temperature from dropping below the safety threshold, avoiding risks such as flooding, and improving the stability of the distillation process and product quality.

[0109] Please refer to Figure 8 , Figure 81 is a schematic diagram of the overall flow of a method for detecting the content of a high-boiling-point solvent in water at the top of a distillation tower provided in an embodiment of the present application, the method comprising the following steps: step S810, determining whether the content of the high-boiling-point solvent in water at the top of the tower is greater than a first preset threshold value; specifically, if so, executing step S820; step S820, obtaining the tower top temperature of the distillation tower; step S830, detecting that the tower top temperature is higher than a second preset threshold value; step S840, obtaining multiple distillation parameters; step S850, determining whether the parameter values of multiple distillation parameters are all within the corresponding multiple first preset ranges; specifically, if so, executing step S851, if not, executing step S860 ; Step S851, obtain multiple feed parameters; Step S852, determine whether the parameter value of at least one feed parameter exceeds the corresponding at least one second preset range; specifically, if so, execute step S853; Step S853, determine the target control plan according to the preset cause query list and the parameter value of at least one feed parameter; Step S860, determine at least one distillation parameter with an abnormal parameter value; Step S870, determine the target control plan according to the cause query list and the parameter value of at least one distillation parameter; Step S880, execute the target control plan; Specifically, after executing step S880, repeat the judgment operation of step S810.

[0110] It can be seen that in this embodiment, the temperature in the tower is used to assist in determining the situation where the content of high-boiling-point solvent in the water at the top of the tower exceeds the standard. When the reboiler steam volume, cooling water flow rate and reflux volume are normal, the feed volume and feed concentration can also cause the concentration of water at the top of the tower to exceed the standard, and then the content of high-boiling-point solvent in the water at the top of the tower is adjusted by adjusting the feed volume and feed concentration; when the reboiler steam volume, cooling water flow rate and reflux volume are abnormal, the condensation amount of the gas phase components at the top of the tower is adjusted by adjusting the values corresponding to the abnormal parameters, thereby reducing the concentration of high-boiling-point solvent in the water at the top of the tower, breaking through the limitations of traditional single parameter adjustment, and realizing accurate and flexible control of the content of high-boiling-point solvent in the water at the top of the distillation tower through the linkage analysis of the top temperature, distillation parameters and feed parameters.

[0111] The above mainly introduces the scheme of the embodiment of the present application from the perspective of the execution process on the method side. It is understandable that in order to realize the above functions, the mobile electronic device includes a hardware structure and / or software module corresponding to the execution of each function. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of each example described in the embodiment provided in this article, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0112] In the embodiments of the present application, the functional units of the electronic device can be divided according to the above method examples. For example, each functional unit can be divided corresponding to each function, or two or more functions can be integrated into one processing unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit. It should be noted that the division of units in the embodiments of the present application is illustrative, only a logical function division, and there can be other division methods in actual implementation.

[0113] Please refer to Figure 9 , Figure 9 which is a schematic diagram of the functional modules of a detection device for the content of high-boiling-point solvents in the overhead water of a rectification column provided by the embodiments of the present application. As Figure 9 shown, the device includes the following modules: A detection module 910, configured to obtain the overhead temperature of the rectification column when it is detected that the content of the high-boiling-point solvent in the overhead water is greater than a first preset threshold; and, if it is detected that the overhead temperature is higher than a second preset threshold, obtain a plurality of rectification parameters, where the plurality of rectification parameters include the overhead reflux flow rate, the cooling water flow rate, and the steam flow rate; A processing module 920, configured to determine whether the parameter values of the plurality of rectification parameters are all within corresponding first preset ranges; if so, obtain a plurality of feed parameters, where the plurality of feed parameters include the waste liquid feed amount and the waste liquid feed concentration; and, determine that the parameter values of at least one feed parameter exceed corresponding at least one second preset range; and, determine a target regulation scheme according to a preset cause query list and the parameter values of the at least one feed parameter, where the cause query list is used to represent a plurality of regulation schemes corresponding to abnormal parameter values of the plurality of rectification parameters and the plurality of feed parameters; and, if not, determine at least one rectification parameter with an abnormal parameter value, and determine the target regulation scheme according to the cause query list and the parameter values of the at least one rectification parameter; An execution module 930, configured to execute the target regulation scheme and detect that the content of the high-boiling-point solvent in the overhead water is less than the first preset threshold after the execution is completed.

[0114] It can be seen that in this embodiment, the situation of excessive content of high-boiling-point solvents in the overhead water is determined by assisting with the tower temperature. When the reboiler steam amount, the cooling water flow rate, and the reflux flow rate are normal, the excessive concentration of the overhead water can also be caused by the feed amount and the feed concentration, and then the content of the high-boiling-point solvent in the overhead water is adjusted by adjusting the feed amount and the feed concentration; when the reboiler steam amount, the cooling water flow rate, and the reflux flow rate are abnormal, the condensation amount of the overhead gas phase components is adjusted by adjusting the corresponding values of the abnormal parameters, so as to reduce the concentration of the high-boiling-point solvent in the overhead water.

[0115] In one embodiment, in terms of determining the target regulation scheme based on the preset cause query list and the parameter values of the at least one feed parameter, the processing module 920 is specifically configured to: if it is determined that the waste liquid feed rate is greater than the maximum threshold of the corresponding second preset feed range, determine the target regulation scheme according to the cause query list as reducing the opening degree of the feed valve to reduce the feed rate of the waste liquid material, and increasing the opening degree of the discharge valve to discharge part of the waste liquid material in the tower through the discharge port and re-participate in the rectification process; if it is determined that the waste liquid feed concentration is greater than the maximum threshold of the corresponding second preset feed concentration range, determine the target regulation scheme according to the cause query list as increasing the opening degree of the reflux valve to increase the top reflux amount, thereby improving the rectification efficiency in the tower; and increasing the opening degree of the cold water valve to increase the cooling water flow rate, thereby ensuring that the gas phase components are fully condensed, so that the content of the high-boiling solvent in the top water is reduced.

[0116] In one embodiment, in terms of determining at least one rectification parameter with abnormal parameter values, the processing module 920 is specifically configured to: determine the preset first reflux amount range corresponding to the top reflux amount, the preset first cooling water flow rate range corresponding to the cooling water flow rate, and the preset first steam flow rate range corresponding to the steam flow rate; if it is determined that the top reflux amount is less than the minimum threshold of the first reflux amount range, determine that the top reflux amount is an abnormal rectification parameter; if it is determined that the cooling water flow rate is less than the minimum threshold of the first cooling water flow rate range, determine that the cooling water flow rate is an abnormal rectification parameter; if it is determined that the steam flow rate is greater than the maximum threshold of the first steam flow rate range, determine that the steam flow rate is an abnormal rectification parameter.

[0117] In one embodiment, in terms of determining the target regulation scheme based on the cause query list and the parameter values of the at least one rectification parameter, the processing module 920 is specifically configured to: if the at least one rectification parameter is the top reflux amount, determine the target regulation scheme according to the cause query list as increasing the opening degree of the reflux valve to increase the top reflux amount, thereby improving the rectification efficiency in the tower by reducing the top temperature; if the at least one rectification parameter is the cooling water flow rate, determine the target regulation scheme according to the cause query list as increasing the opening degree of the cold water valve to increase the cooling water flow rate, thereby ensuring that the gas phase components are fully condensed, so that the content of the high-boiling solvent in the top water is reduced; if the at least one rectification parameter is the steam flow rate, determine the target regulation scheme according to the cause query list as reducing the opening degree of the steam valve to reduce the steam flow rate, thereby stabilizing the gas-liquid balance in the tower and preventing the gas phase components from being not fully condensed and dissolved in the top water due to the rapid rise of water vapor in the tower.

[0118] In one embodiment, after executing the target regulation scheme, the processing module 920 is further configured to: if it is detected that the concentration of the waste liquid feed decreases, reduce the opening degree of the reflux valve to reduce the top reflux flow rate, and reduce the opening degree of the cold water valve to reduce the cooling water flow rate.

[0119] In one embodiment, after executing the target regulation scheme, the processing module 920 is further configured to: detect a decrease in the top temperature; determine a lowest temperature threshold corresponding to the top temperature, where the lowest temperature threshold is a preset lowest temperature value that the top of the distillation column can adapt to when the distillation column can maintain normal operation; adjust the parameter values of the at least one distillation parameter according to the decreasing speed of the top temperature, so as to prevent the top temperature from dropping below the lowest temperature threshold.

[0120] In one embodiment, in terms of adjusting the parameter values of the at least one distillation parameter according to the decreasing speed of the top temperature, the processing module 920 is specifically configured to: determine a target speed according to the decreasing speed of the top temperature; adjust the opening degree of at least one valve corresponding to the at least one distillation parameter according to the target speed, so that the parameter values of the at least one distillation parameter decrease or increase according to the target speed.

[0121] In one embodiment, in terms of adjusting the opening degree of at least one valve corresponding to the at least one distillation parameter according to the target speed, so that the parameter values of the at least one distillation parameter decrease or increase according to the target speed, the processing module 920 is specifically configured to: if the at least one distillation parameter is the top reflux flow rate, reduce the opening degree of the reflux valve, so that the top reflux flow rate decreases according to the target speed; if the at least one distillation parameter is the cooling water flow rate, reduce the opening degree of the cold water valve, so that the cooling water flow rate decreases according to the target speed; if the at least one distillation parameter is the steam flow rate, increase the opening degree of the steam valve, so that the steam flow rate increases according to the target speed.

[0122] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center in a wired or wireless manner. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or a data center that contains one or more collections of available media. The available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media. The semiconductor media can be a solid-state drive.

[0123] The embodiments of the present application also provide a computer storage medium, on which computer programs / instructions are stored. When the computer programs / instructions are executed by a processor, part or all of the steps of any of the methods described in the above method embodiments are implemented.

[0124] The embodiments of the present application also provide a computer program product. The computer program product includes a non-transitory computer-readable storage medium storing a computer program. The computer program is operable to cause a computer to execute part or all of the steps of any of the methods described in the above method embodiments.

[0125] It should be understood that in various embodiments of the present application, the sequence numbers of the above processes do not mean the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0126] In several embodiments provided by the present application, it should be understood that the disclosed methods, apparatuses, and systems can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling, direct coupling, or communication connection to each other can be through some interfaces. The indirect coupling or communication connection of the apparatuses or units can be in an electrical, mechanical, or other form.

[0127] The unit described as a separate component may or may not be physically separated. The component shown as a unit may or may not be a physical unit, that is, it may be located in one place or distributed over multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0128] In addition, each functional unit in various embodiments of the present invention may be integrated in a processing unit, or each unit may be physically included separately, or two or more units may be integrated in one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a hardware plus software functional unit.

[0129] The above-mentioned integrated unit implemented in the form of a software functional unit can be stored in a computer-readable storage medium. The above-mentioned software functional unit stored in a storage medium includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute some steps of the methods in various embodiments of the present invention. The foregoing storage medium includes: USB flash drive, mobile hard disk, magnetic disk, optical disk, volatile memory or non-volatile memory. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example but not limitation, many forms of random access memory (RAM) are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct rambus random access memory (DRRAM), etc., all of which are media that can store program code.

[0130] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can easily conceive of changes or substitutions without departing from the spirit and scope of the present invention, and can make various modifications and alterations, including combinations of the above different functions and implementation steps, including software and hardware implementation manners, all within the protection scope of the present invention.

Claims

1. A method for detecting the content of high-boiling solvents in the water at the top of a distillation column, characterized in that, The rectification column purifies the high-boiling solvent by rectifying the waste liquid at the bottom of the column. A reboiler is provided at the bottom of the rectification column, and the gas outlet at the top of the column is connected to a condenser and a reflux drum in sequence through a pipeline. Among them, the reboiler is connected to hot steam to heat and rectify the waste liquid at the bottom of the column, and the condenser is connected to cooling water to condense the gas components discharged from the gas outlet at the top of the column to obtain a mixed liquid phase. In the reflux drum, the mixed liquid phase is stratified to form a liquid phase component and the top water mainly composed of liquid water. The liquid phase component is refluxed to the top of the rectification column to continue rectification and purification. The method includes: When it is detected that the content of the high-boiling solvent in the top water is greater than a first preset threshold, obtain the top temperature of the rectification column; If it is detected that the top temperature is higher than a second preset threshold, obtain a plurality of rectification parameters, and the plurality of rectification parameters include the top reflux flow rate, the cooling water flow rate, and the steam flow rate; Judge whether the parameter values of the plurality of rectification parameters are all within corresponding first preset ranges; If so, obtain a plurality of feed parameters, and the plurality of feed parameters include the waste liquid feed rate and the waste liquid feed concentration; and, judge that the parameter values of at least one feed parameter exceed corresponding at least one second preset range; and, determine a target regulation scheme according to a preset cause query list and the parameter values of the at least one feed parameter, and the cause query list is used to represent a plurality of regulation schemes corresponding to abnormal parameter values of the plurality of rectification parameters and the plurality of feed parameters; and, If not, determine at least one rectification parameter with abnormal parameter values, and determine the target regulation scheme according to the cause query list and the parameter values of the at least one rectification parameter; Execute the target regulation scheme, and after the execution is completed, it is detected that the content of the high-boiling solvent in the top water is less than the first preset threshold.

2. The method according to claim 1, wherein The reboiler is connected to a steam valve, and the steam valve is used to regulate the steam flow rate of the hot steam. The condenser is connected to a cold water valve, and the cold water valve is used to regulate the cooling water flow rate of the cooling water. The reflux drum is connected to a reflux valve, and the reflux valve is used to regulate the reflux flow rate of the liquid phase component refluxed to the top of the column. The liquid phase component is the high-boiling solvent after this rectification and purification; The tower body of the rectification column is also provided with a feed port and a discharge port. The feed port is connected to a feed valve, and the feed valve is used to regulate the feed rate of the waste liquid material input into the column. The discharge port is connected to a discharge valve, and the discharge valve is used to output the high-purity product corresponding to the high-boiling solvent after multiple refluxes and purifications. In addition, the discharge valve is also used to control the discharge rate of the waste liquid material in the column under abnormal conditions.

3. The method according to claim 2, characterized in that, The formation process of the top water is as follows: the waste liquid is placed in the column kettle of the rectification column through the feed port; the column kettle is connected to the reboiler through a liquid phase pipeline to transport the waste liquid into the reboiler; the reboiler is connected to hot steam to heat and rectify the waste liquid to obtain the gas components, and the reboiler is connected to the rectification column through a gas phase pipeline to transport the gas components back into the rectification column; The gas-phase components are discharged from the top of the tower gas outlet to the condenser; The condenser is connected to cooling water to condense the gas-phase components to obtain the mixed liquid phase, and the mixed liquid phase is transported to the reflux drum; the mixed liquid phase is separated by stratification in the reflux drum to obtain the liquid-phase components and the overhead water.

4. The method according to any one of claims 1 to 3, characterized in that, Determining the target regulation scheme according to the preset cause query list and the parameter values of the at least one feed parameter includes: If it is determined that the waste liquid feed rate is greater than the maximum threshold of the corresponding second preset feed range, the target regulation scheme is determined according to the cause query list to reduce the opening degree of the feed valve to reduce the feed rate of the waste liquid material, and increase the opening degree of the discharge valve to discharge part of the waste liquid material in the tower through the discharge port and participate in the rectification process again; If it is determined that the waste liquid feed concentration is greater than the maximum threshold of the corresponding second preset feed concentration range, the target regulation scheme is determined according to the cause query list to increase the opening degree of the reflux valve to increase the overhead reflux flow rate, thereby improving the rectification efficiency in the tower; and, increase the opening degree of the cold water valve to increase the cooling water flow rate, thereby ensuring that the gas-phase components are fully condensed, so that the content of the high-boiling solvent in the overhead water is reduced.

5. The method according to claim 4, wherein The at least one rectification parameter for determining the abnormal parameter value includes: Determining the preset first reflux flow rate range corresponding to the overhead reflux flow rate, the preset first cooling water flow rate range corresponding to the cooling water flow rate, and the preset first steam flow rate range corresponding to the steam flow rate; If it is determined that the overhead reflux flow rate is less than the minimum threshold of the first reflux flow rate range, the overhead reflux flow rate is determined as an abnormal rectification parameter; If it is determined that the cooling water flow rate is less than the minimum threshold of the first cooling water flow rate range, the cooling water flow rate is determined as an abnormal rectification parameter; If it is determined that the steam flow rate is greater than the maximum threshold of the first steam flow rate range, the steam flow rate is determined as an abnormal rectification parameter.

6. The method according to claim 5, characterized in that, Determining the target regulation scheme according to the cause query list and the parameter values of the at least one rectification parameter includes: If the at least one rectification parameter is the overhead reflux flow rate, the target regulation scheme is determined according to the cause query list to increase the opening degree of the reflux valve to increase the overhead reflux flow rate, thereby improving the rectification efficiency in the tower by reducing the overhead temperature; If the at least one rectification parameter is the cooling water flow rate, the target regulation scheme is determined according to the cause query list to increase the opening degree of the cold water valve to increase the cooling water flow rate, thereby ensuring that the gas-phase components are fully condensed, so that the content of the high-boiling solvent in the overhead water is reduced; If the at least one rectification parameter is the steam flow rate, the target regulation scheme is determined according to the cause query list to reduce the opening degree of the steam valve to reduce the steam flow rate, thereby stabilizing the gas-liquid balance in the tower and preventing the gas-phase components from being not fully condensed and dissolved in the overhead water due to the rapid rise of water vapor in the tower.

7. The method according to claim 6, characterized in that After executing the target regulation scheme, the method further includes: If it is detected that the concentration of the waste liquid feed decreases, the opening degree of the reflux valve is reduced to decrease the reflux flow rate at the top of the column, and the opening degree of the cold water valve is reduced to decrease the cooling water flow rate.

8. The method according to claim 7, characterized in that After implementing the target regulation scheme, the method further includes: Detecting a decrease in the temperature at the top of the column; Determining a lowest temperature threshold corresponding to the temperature at the top of the column, where the lowest temperature threshold is a preset lowest temperature value that the temperature at the top of the column can adapt to when the rectification column can maintain normal operation; Adjusting the parameter values of the at least one rectification parameter according to the decreasing speed of the temperature at the top of the column to prevent the temperature at the top of the column from dropping below the lowest temperature threshold.

9. The method according to claim 8, wherein The adjusting the parameter values of the at least one rectification parameter according to the decreasing speed of the temperature at the top of the column includes: Determining a target speed according to the decreasing speed of the temperature at the top of the column; Adjusting the opening degree of at least one valve corresponding to the at least one rectification parameter according to the target speed, such that the parameter values of the at least one rectification parameter decrease or increase at the target speed.

10. The method according to claim 9, wherein The adjusting the opening degree of at least one valve corresponding to the at least one rectification parameter according to the target speed, such that the parameter values of the at least one rectification parameter decrease or increase at the target speed, includes: If the at least one rectification parameter is the reflux flow rate at the top of the column, reducing the opening degree of the reflux valve, such that the reflux flow rate at the top of the column decreases at the target speed; If the at least one rectification parameter is the cooling water flow rate, reducing the opening degree of the cold water valve, such that the cooling water flow rate decreases at the target speed; If the at least one rectification parameter is the steam flow rate, increasing the opening degree of the steam valve, such that the steam flow rate increases at the target speed.

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