Acetaldehyde rectification process and residual liquid recovery method based on remote supervision of Internet of Things

Abstract

The invention discloses an acetaldehyde rectification process based on remote supervision of Internet of Things and a residual liquid recovery method, relates to the technical field of acetaldehyde rectification, and aims to solve the problems that the existing acetaldehyde rectification process is incomplete and the residual liquid recovery effect is poor. By monitoring the residual capacity of the channel in real time, it is ensured that the selected channel can bear the data transmission quantity, transmission can be completed at the fastest speed, data congestion and transmission delay are avoided, the continuity and integrity of production data are ensured through a timing acquisition mechanism, key node data can be accurately captured through an event triggering mechanism, and the data transmission efficiency is improved. The two acquisition mechanisms are complementary, data omission and delay are avoided, preliminary and secondary analysis results and standard data are compared and evaluated, a scientific and unified quality judgment standard is established, subjectivity of manual judgment is avoided, and it is ensured that each batch of acetaldehyde meets the quality requirement.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of acetaldehyde rectification, in particular to an acetaldehyde rectification process and residual liquid recovery method based on Internet of Things remote supervision. BACKGROUND

[0002] Acetaldehyde rectification is a process of separating and purifying a mixture by rectification technology based on the difference in volatility between acetaldehyde and other components, and is a key link in the acetaldehyde production or recovery process.

[0003] A Chinese patent with publication number CN206447797U discloses an acetaldehyde recovery system, which mainly uses the physical properties of specific polyester esterification water and combines the principle of reactive distillation to improve the decomposition rate of 2-methyl-1,3-dioxolane in esterification wastewater, thereby achieving higher acetaldehyde yield compared to the background technology. At the same time, the integration of acetaldehyde rectification and polyester process column is used to realize low energy consumption of acetaldehyde recovery and purification. Although the above patent solves the problem of acetaldehyde recovery, there are still the following problems in actual operation:

[0004] 1. The cooling and liquefaction step in the acetaldehyde rectification process is not handled more perfectly, resulting in unstable acetaldehyde cooling and liquefaction.

[0005] 2. A more perfect reflux method is not used for reflux treatment, resulting in poor residual liquid collection effect.

[0006] 3. The recovery step of residual liquid cannot be more accurately managed and controlled, resulting in unclear and perfect process of acetaldehyde rectification. SUMMARY

[0007] The present application aims to provide an acetaldehyde rectification process and residual liquid recovery method based on Internet of Things remote supervision, which ensures that the selected channel can not only carry data transmission volume but also complete transmission at the fastest speed by monitoring the remaining capacity of the real-time channel, avoids data congestion and transmission delay, ensures the continuity and integrity of production data through a timed collection mechanism, accurately captures key node data through an event triggering mechanism, quickly locates the root cause of the problem, improves emergency response speed, and the two collection mechanisms complement each other to avoid data omission and delay. The preliminary and secondary analysis results are compared and evaluated with standard data to establish a scientific and unified quality judgment standard, avoid the subjectivity of human judgment, and ensure that each batch of acetaldehyde meets the quality requirements, which can solve the problems in the prior art.

[0008] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0009] The acetaldehyde rectification process based on Internet of Things remote supervision comprises:

[0010] The acetaldehyde raw material is transported into the rectifying tower, the rectifying process is performed on the raw material in the rectifying tower, the high-temperature acetaldehyde vapor rising from the top of the rectifying tower is cooled and liquefied after the rectifying process, the acetaldehyde liquid after the cooling and liquefaction treatment is returned to the rectifying tower for reflux treatment, and finally the refluxed acetaldehyde is qualified for detection, and the detected acetaldehyde is collected and stored.

[0011] Preferably, the acetaldehyde raw material is transported into the rectifying tower, including:

[0012] The acetaldehyde raw material is a mixed raw material, and the mixed raw material is connected to the raw material storage tank through a pipeline, wherein the raw material storage tank is provided with a liquid level sensor for real-time monitoring of the liquid level of the mixed raw material in the raw material storage tank.

[0013] When the liquid level of the mixed raw material is lower than the set minimum threshold, an alarm is automatically triggered and the replenishment of raw materials is prompted.

[0014] The delivery pump extracts the mixed raw material from the raw material storage tank, wherein the flow of the delivery pump is controlled by the flow regulating valve, and at the same time, the flow regulating valve and the flow sensor form a closed loop control.

[0015] After the mixed raw material is extracted from the raw material storage tank, it passes through a filter, and the filter filters the impurities in the mixed raw material.

[0016] After filtration, it is transported to the rectifying tower through a pipeline.

[0017] Preferably, the rectifying process is performed on the raw material in the rectifying tower, including:

[0018] A reboiler is arranged at the bottom of the rectifying tower, and the reboiler is heated by steam, and after heating, part of the mixed raw material in the kettle is vaporized, and the steam generated after the vaporization of part of the mixed raw material rises along the tray plate by plate.

[0019] Wherein, the rectifying tower is provided with multiple layers of tray plates, and each layer of tray plate is provided with a gas-liquid contact device.

[0020] On each tray plate, the steam exchanges heat and mass with the liquid flowing down from above, the low-boiling-point acetaldehyde component continuously vaporizes and rises, and the high-boiling-point heavy component continuously condenses and returns to the kettle.

[0021] Finally, the rectification of the mixed raw material is completed.

[0022] Preferably, the high-temperature acetaldehyde vapor rising from the top of the rectifying tower is cooled and liquefied, including:

[0023] The acetaldehyde steam discharged from the top of the rectification tower enters a condenser, wherein, at the inlet and outlet of the cooling water of the condenser, temperature sensors and flow sensors are installed; the temperature sensors monitor the temperature of the cooling water when entering and leaving the condenser in real time, and the flow sensors accurately control the flow of the cooling water;

[0024] The condenser adopts a shell-and-tube heat exchanger, and the internal structure of the condenser includes a plurality of heat exchange tubes; the high-temperature acetaldehyde steam flows in the tube side, and the cooling water flows in the shell side to exchange heat through the tube wall;

[0025] The cooling water enters from the bottom of the condenser and flows upwards along the shell side to form countercurrent heat exchange with the high-temperature acetaldehyde steam flowing downwards in the tube side;

[0026] When the temperature drops below the boiling point of acetaldehyde, the steam begins to liquefy and changes from a gaseous state to a liquid state;

[0027] The outlet of the condenser is provided with a gas-liquid separator for separating a small amount of acetaldehyde steam that has not completely liquefied from the liquefied acetaldehyde liquid;

[0028] The steam that has not been liquefied at the top of the gas-liquid separator is returned to the rectification tower through a pipeline for further rectification treatment, and finally completes the cooling and liquefaction treatment.

[0029] Preferably, the acetaldehyde liquid after the cooling and liquefaction treatment is returned to the rectification tower for reflux treatment, including:

[0030] The liquefied acetaldehyde liquid after the liquefaction treatment is gathered at the bottom of the gas-liquid separator and flows into a reflux buffer tank through a discharge pipeline;

[0031] A reflux pump is installed on the outlet pipeline of the reflux buffer tank, and the control system sets the starting parameters of the reflux pump according to the operating state of the rectification tower;

[0032] After the reflux pump is started, the centrifugal force generated by the high-speed rotation of the impeller extracts the acetaldehyde liquid from the reflux buffer tank and pressurizes it into a reflux pipeline;

[0033] A flow regulating valve and a flow sensor are arranged on the reflux pipeline, and the flow regulating valve and the flow sensor form a closed-loop control circuit; the flow sensor monitors the reflux liquid flow in real time and feeds back the data to the control system;

[0034] Finally, the reflux treatment of the acetaldehyde liquid is completed.

[0035] Preferably, the refluxed acetaldehyde is subjected to qualified detection, and the acetaldehyde that passes the detection is collected and stored, including:

[0036] The infrared spectrometer is used for preliminary analysis of the refluxed acetaldehyde. The preliminary analysis is to identify the specific spectral absorption peaks of acetaldehyde molecules, and to judge whether the purity requirement is met. The ion impurity content in the acetaldehyde is monitored in real time by the conductivity meter, and the water content in the acetaldehyde is detected by the water content detector.

[0037] After the preliminary analysis, secondary analysis is performed. The secondary analysis includes detecting high-boiling organic impurities by high-performance liquid chromatography, detecting trace metal element impurities by atomic absorption spectrometry, and performing physical property detection.

[0038] The results of the preliminary analysis and the secondary analysis are compared and evaluated with the standard analysis data.

[0039] According to the comparison and evaluation results, the qualified acetaldehyde is transported to the finished product collection area through a pipeline. The collection area is provided with a plurality of finished product storage tanks, each of which is marked with a number, a volume, a storage time, and storage medium information.

[0040] According to the storage requirements, the acetaldehyde in the finished product storage tank is stored in a low-temperature storage tank. The low-temperature storage tank is provided with a heat insulation layer outside and is equipped with a cooling system to maintain a low-temperature environment in the tank. The temperature of the low-temperature environment is between 0-5℃. A pressure sensor and a liquid level sensor are installed on the top of the storage tank.

[0041] Finally, the collection and storage of qualified acetaldehyde are completed.

[0042] The method for recovering residual liquid in an acetaldehyde rectification process based on remote monitoring of the Internet of Things, comprising:

[0043] Collecting process parameter data in the acetaldehyde rectification process, processing and transmitting the collected process parameter data, receiving the transmitted process parameters, and adjusting and controlling the equipment according to the received process parameters.

[0044] Preferably, the process parameter data in the acetaldehyde rectification process is collected, comprising:

[0045] First, the sensors corresponding to each link in the acetaldehyde rectification process are confirmed, including the liquid level sensor, temperature sensor, and pressure sensor installed on the raw material storage tank; the temperature sensor, pressure sensor, gas flow sensor, and flow sensor installed on the inlet and outlet of the rectifying tower bottom reboiler; the temperature sensor, pressure sensor, liquid level sensor, and flow sensor installed on the inlet and outlet of the condenser; the flow regulating valve, flow sensor on the reflux pipeline, and the current and voltage sensors of the reflux pump;

[0046] After the sensor confirmation, the data collection mechanism is customized, including a timing collection mechanism or an event-triggered collection mechanism.

[0047] The timing acquisition mechanism sets a fixed acquisition period, sends data reading instructions to each sensor in turn according to a preset time interval, and the sensor acquires the real-time monitored parameter data after receiving the instruction;

[0048] The event-triggered acquisition mechanism triggers data acquisition immediately when a specific event occurs in the process;

[0049] After acquisition, process parameter data is obtained.

[0050] Preferably, the acquired process parameter data is processed and transmitted, including:

[0051] The acquired process parameter data is first integrated, and a parameter data set is obtained after data integration;

[0052] The parameter data set is cleaned, which is an abnormal value processing, repeated value removal and missing value supplement;

[0053] After data cleaning, data standardization processing is performed;

[0054] The data after standardization processing is transmitted to the control center, and the transmission speed of the transmission channel is automatically selected when the data is transmitted;

[0055] The transmission amount of the data after standardization processing is confirmed, the number of transmission channels is not less than four, and the channel residual capacity of each transmission channel is monitored in real time;

[0056] The transmission channel with a data transmission amount less than the channel residual capacity is selected as the final transmission channel of the data.

[0057] Preferably, the equipment is regulated according to the received process parameters, including:

[0058] The control center receives the transmitted process parameter data, judges the received process parameter data, and screens out abnormal parameter data in the process parameter data according to the judgment result;

[0059] The abnormal reasons of the abnormal parameter data are analyzed;

[0060] According to the correlation analysis result, the control instruction is generated, and finally the generated control instruction is matched with the process equipment;

[0061] After the matching is completed, the instruction is issued, and the process equipment adjusts the equipment according to the issued instruction.

[0062] Compared with the prior art, the beneficial effects of the present application are as follows:

[0063] 1.The acetaldehyde distillation process and residual liquid recovery method based on Internet of Things remote monitoring provided by the present application can flexibly adjust the amount and temperature of cooling water according to the actual situation of steam by precisely controlling the temperature and flow, which not only ensures the cooling effect, but also avoids water resource waste and energy consumption increase, ensures the stable and efficient operation of the entire cooling liquefaction process, adopts a shell-and-tube heat exchanger, cooling water and high-temperature acetaldehyde steam form countercurrent heat exchange to increase the heat transfer temperature difference; temperature sensors and flow sensors are installed at the inlet and outlet of the cooling water to monitor in real time and adjust the cooling water flow and temperature through closed-loop control, which can dynamically adjust the cooling parameters according to the actual state of the steam to ensure that the acetaldehyde steam is quickly reduced to below the boiling point for liquefaction, and avoid the waste of energy caused by insufficient cooling or excessive cooling.

[0064] 2.The acetaldehyde distillation process and residual liquid recovery method based on Internet of Things remote monitoring provided by the present application compares and evaluates the primary and secondary analysis results with standard data to establish a scientific and unified quality judgment standard, avoids the subjectivity of human judgment, ensures that each batch of acetaldehyde meets the quality requirements, and the control system sets the reflux pump start parameters according to the real-time operation state of the distillation column, and combines the closed-loop control loop composed of the flow regulating valve and the flow sensor on the reflux pipeline to accurately adjust the acetaldehyde liquid reflux amount, the reflux pump start parameters are dynamically set according to the operation state of the distillation column, the flow regulating valve and the flow sensor on the reflux pipeline form a closed loop, the reflux amount is adjusted in real time, the automatic control of the reflux system can quickly and stably control the working condition in the tower, improve the distillation efficiency and product purity, and at the same time reduce the error caused by manual intervention.

[0065] 3.The acetaldehyde distillation process and residual liquid recovery method based on Internet of Things remote monitoring provided by the present application ensures the continuity and integrity of production data through a timed collection mechanism, and can accurately capture key node data through an event triggering mechanism, which is convenient for quickly locating the root cause of the problem, improves the emergency response speed, and avoids data omission and delay through the complementation of the two collection mechanisms, real-time monitoring of the remaining capacity of the channel ensures that the selected channel can not only carry the data transmission amount, but also complete the transmission at the fastest speed, avoiding data congestion and transmission delay. BRIEF DESCRIPTION OF DRAWINGS

[0066] Figure 1 It is a schematic diagram of the acetaldehyde distillation process of the present application;

[0067] Figure 2 It is a schematic diagram of the residual liquid recovery method of the present application. DETAILED DESCRIPTION

[0068] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0069] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application. Figure 1 Figure 2 The present embodiment provides the following technical solutions:

[0070] The acetaldehyde distillation process based on Internet of Things remote supervision comprises:

[0071] The raw material of acetaldehyde is transported into the distillation column, and the raw material in the distillation column is subjected to distillation process treatment. The high-temperature acetaldehyde vapor rising from the top of the distillation column is subjected to cooling and liquefaction treatment. The acetaldehyde liquid after the cooling and liquefaction treatment is returned to the distillation column for reflux treatment. Finally, the acetaldehyde after the reflux is subjected to qualified detection. The acetaldehyde that passes the detection is collected and stored.

[0072] Specifically, the Internet of Things sensors are used to collect the parameters such as the temperature and pressure of the distillation column in real time. The remote system accurately controls the heating power and reflux ratio according to the parameters, so as to ensure that the distillation is in the best state and improve the purity and yield of acetaldehyde. The automatic adjustment instruction quickly responds to the abnormality, reduces the manual operation delay, and ensures the continuity of production. The operating data and process trends of the equipment can be remotely viewed by the operator, and the whole process can be visually monitored. The system can predict equipment failure based on historical data, perform maintenance in advance, and reduce downtime. The accumulated data can also be used for process optimization to improve overall performance. Acetaldehyde is flammable and explosive, and remote control reduces the number of personnel entering the dangerous area. The system integrates an emergency stop function to improve safety. At the same time, automatic storage of operation data facilitates traceability and meets regulatory requirements. In addition, precise control reduces energy consumption and labor costs, reduces material waste and inventory accumulation, realizes cost reduction and efficiency improvement, supports rapid switching of process formulas, flexibly adjusts production modes, adapts to multi-variety production demands, and has strong system expandability, facilitating integration with other production links and management systems. The efficiency of the cooling liquid treatment is shown in the table:

[0073]

[0074] The raw material of acetaldehyde is transported into the distillation column, and the raw material in the distillation column is subjected to distillation process treatment. The high-temperature acetaldehyde vapor rising from the top of the distillation column is subjected to cooling and liquefaction treatment. The acetaldehyde liquid after the cooling and liquefaction treatment is returned to the distillation column for reflux treatment. Finally, the acetaldehyde after the reflux is subjected to qualified detection. The acetaldehyde that passes the detection is collected and stored.

[0075] The raw material of acetaldehyde is mixed raw material, which is connected to the raw material storage tank through a pipeline. The raw material storage tank is equipped with a liquid level sensor for real-time monitoring of the liquid level of the mixed raw material in the raw material storage tank.

[0076] When the liquid level of the mixed raw material is lower than the set minimum threshold, an automatic alarm is triggered, and the replenishment of raw material is prompted.​

[0077] The conveying pump extracts the mixed raw materials from the raw material storage tank, wherein the flow of the conveying pump is controlled by the flow regulating valve, and the flow regulating valve and the flow sensor form a closed loop control;

[0078] After the mixed raw materials are extracted from the raw material storage tank, they pass through the filter, which filters the impurities in the mixed raw materials;

[0079] After the filtration is completed, the mixed raw materials are conveyed to the rectification tower through the pipeline.

[0080] Specifically, the liquid level sensor monitors the liquid level of the raw material storage tank in real time, and automatically triggers an alarm and prompts to replenish the raw materials when the liquid level of the mixed raw materials is below the minimum threshold, avoiding production interruption caused by shortage of raw materials. This automatic early warning mechanism can effectively reduce the risk of production stagnation caused by human inspection omissions, ensure the continuous and stable operation of the rectification process, and accurately adjust the delivery amount of the mixed raw materials according to the production demand. Compared with manual adjustment, the closed loop control system reacts quickly and accurately, which can avoid unstable working conditions in the rectification tower caused by flow fluctuations, thereby improving the quality and production efficiency of acetaldehyde products. The mixed raw materials pass through the filter before entering the rectification tower, which can effectively remove impurities. This not only reduces the blockage and wear of the equipment such as tower plate and pipeline in the rectification tower, prolongs the service life of the equipment, but also reduces the interference of impurities on the rectification process, which helps to improve the purity of acetaldehyde products and reduce the production of substandard products. The liquid level monitoring and flow control are automated, reducing the workload of frequent manual inspection and adjustment and reducing labor costs. At the same time, the raw material conveying process is remotely controllable, and the operator does not need to frequently approach dangerous areas such as storage tanks, reducing the safety risks caused by contact with flammable and explosive acetaldehyde raw materials.

[0081] The rectification process is performed on the raw materials in the rectification tower, including:

[0082] A reboiler is arranged at the bottom of the rectification tower, which is heated by steam. After heating, part of the mixed raw materials in the tower kettle vaporize, and the steam generated after the vaporization of part of the mixed raw materials rises along the tower plate by plate;

[0083] Among them, multiple layers of tower plates are arranged in the rectification tower, and gas-liquid contact devices are arranged on each tower plate;

[0084] On each tower plate, the steam exchanges heat and mass with the liquid flowing down from above, the low-boiling-point acetaldehyde components continuously vaporize and rise, and the high-boiling-point heavy components continuously condense and flow back to the tower kettle;

[0085] Finally, the rectification process of the mixed raw materials is completed.

[0086] Specifically, the rectification tower is designed with multiple layers of trays and gas-liquid contact devices to build a dense gas-liquid mass transfer interface. The reverse contact of steam and liquid on each tray allows low-boiling acetaldehyde (light component) and high-boiling heavy components to be separated through multiple vaporization-condensation cycles. This "tray-by-tray concentration" mechanism can precisely control the distribution of different components: acetaldehyde continuously vaporizes and rises to the top of the tower to be enriched, while heavy components condense and flow back to the tower bottom, ultimately achieving efficient separation of each component in the mixed raw material, especially suitable for fine separation of near-boiling or azeotropic systems. The tower bottom reboiler uses indirect steam heating to avoid contamination of the raw material by direct heating, and the stable steam heat source can accurately regulate the vaporization rate in the tower to ensure the stability of the rectification process. The vaporized steam serves as the rising gas phase to carry energy from tray to tray, while the reflux of the condensate at the top forms a liquid phase cycle. This mechanism of "heat transfer from top to bottom and mass transfer from bottom to top" achieves step-by-step utilization of energy. Compared to single-stage distillation, the rectification process reduces energy consumption through multiple gas-liquid exchanges, significantly reducing energy consumption per unit of separation, especially suitable for large-scale continuous production scenarios. The modular design of the multi-layer trays provides flexibility to the process: by adjusting the number of trays, gas-liquid flow rate (such as reflux ratio), and heating steam volume, the process can adapt to different raw material compositions, separation precision, and production capacity requirements. For example, increasing the number of trays can improve separation purity, and increasing the reflux ratio can optimize light component recovery. In addition, the temperature, pressure, and other parameters of each tray in the tower can be monitored and adjusted in real time, allowing operators to quickly adjust process parameters based on changing operating conditions to ensure stable operation in the efficient range and reduce production risks caused by fluctuations in raw materials.

[0087] The high-temperature acetaldehyde steam rising from the top of the rectification tower is cooled and liquefied, including:

[0088] The acetaldehyde steam discharged from the top of the rectification tower enters the condenser, wherein temperature sensors and flow sensors are installed at the inlet and outlet of the cooling water of the condenser; the temperature sensors monitor the temperature of the cooling water entering and leaving the condenser in real time, and the flow sensors accurately control the flow of the cooling water;

[0089] The condenser uses a shell-and-tube heat exchanger, and the internal structure of the condenser includes multiple heat exchange tubes. High-temperature acetaldehyde steam flows in the tube side, and cooling water flows in the shell side, exchanging heat through the tube wall.

[0090] The cooling water enters from the bottom of the condenser and flows upwards along the shell side, forming countercurrent heat exchange with the high-temperature acetaldehyde steam flowing downwards in the tube side.

[0091] When the temperature drops below the boiling point of acetaldehyde, the steam begins to liquefy, changing from a gaseous state to a liquid state.

[0092] The gas-liquid separator is arranged at the outlet of the condenser and is used to separate the small amount of acetaldehyde steam that is not completely liquefied from the acetaldehyde liquid that has been liquefied.

[0093] The steam that is not liquefied at the top of the gas-liquid separator is returned to the rectifying tower for rectification again, and finally completes the cooling liquefaction treatment.

[0094] Specifically, the shell-and-tube heat exchanger is used as the condenser, and the plurality of heat exchange tubes inside the condenser increase the heat transfer area and create good conditions for heat exchange. At the same time, the cooling water flows from bottom to top in the shell side, and the high-temperature acetaldehyde steam flows from top to bottom in the tube side, forming countercurrent heat exchange. Compared with the parallel flow heat exchange, this mode can perform heat transfer at a larger temperature difference, and can make the steam drop below the boiling point of acetaldehyde more quickly, thereby greatly improving the cooling liquefaction efficiency. Temperature sensors and flow sensors are installed at the inlet and outlet of the condenser, so as to monitor the temperature and flow of the cooling water in real time. Through accurate control of the temperature and flow, the amount and temperature of the cooling water can be flexibly adjusted according to the actual situation of the steam, so as to ensure the cooling effect, avoid waste of water resources and increase of energy consumption, and ensure stable and efficient operation of the entire cooling liquefaction process. The gas-liquid separator arranged at the outlet of the condenser can accurately separate the small amount of acetaldehyde steam that is not completely liquefied from the acetaldehyde liquid that has been liquefied. The steam that is not liquefied at the top is returned to the rectifying tower for rectification again. This design not only improves the recovery rate of acetaldehyde, but also reduces the waste of raw materials, further improves the purity of the final product, reduces the production cost, and realizes efficient use of resources.

[0095] In order to solve the problem that the residual liquid is not collected by using a more perfect reflux mode for reflux treatment in the prior art, thereby resulting in poor residual liquid collection effect, please refer to Figure 1 and Figure 2 The embodiment provides the following technical scheme:

[0096] The acetaldehyde liquid after the cooling liquefaction treatment is returned to the rectifying tower for reflux treatment, including:

[0097] The acetaldehyde liquid that has been liquefied after the liquefaction treatment is gathered at the bottom of the gas-liquid separator and flows into the reflux buffer tank through a discharge pipeline;

[0098] A reflux pump is installed on the outlet pipeline of the reflux buffer tank, and the starting parameters of the reflux pump are set by the control system according to the operating state of the rectifying tower;

[0099] After the reflux pump is started, the centrifugal force generated by high-speed rotation of an impeller is used to pump the acetaldehyde liquid out of the reflux buffer tank and into the reflux pipeline;

[0100] The flow regulating valve and the flow sensor are arranged on the reflux pipeline, and the flow regulating valve and the flow sensor form a closed-loop control circuit, the flow sensor monitors the reflux liquid flow in real time, and feeds back data to the control system.

[0101] Finally, the reflux treatment of the acetaldehyde liquid is completed.

[0102] Specifically, the gas-liquid separator converges the liquefied acetaldehyde liquid at the bottom and flows into the reflux buffer tank through the discharge pipeline to provide stable material reserves for subsequent reflux. This design avoids unstable transportation caused by gas-liquid mixing, ensures that the reflux pump always extracts liquid acetaldehyde, prevents the gas erosion phenomenon from damaging the equipment, guarantees the reliable operation of the reflux system, and controls the system to set the reflux pump start-up parameters according to the real-time operation state of the rectifying column, combined with the closed-loop control circuit formed by the flow regulating valve and the flow sensor on the reflux pipeline, to accurately adjust the acetaldehyde liquid reflux flow. For example, when the rectifying column top temperature rises, the system automatically increases the reflux flow to strengthen the cooling effect, quickly and stably stabilizes the tower working condition, improves the acetaldehyde rectification efficiency and product purity, and through dynamic adjustment of the reflux pump parameters and the reflux flow, this scheme can flexibly adapt to different production requirements and working condition changes. Whether the raw material composition fluctuates or the product quality standard is adjusted, the system can quickly respond, automatically optimize the reflux strategy, ensure that the rectification process can efficiently operate under various conditions, enhance the flexible production capacity of the production line, and fully automate the reflux process. Reducing manual adjustment of the reflux flow reduces labor costs, avoids abnormal reflux flow caused by human error, and ensures production safety. In addition, operators do not need to frequently adjust the equipment, reducing the risk of contact with flammable and explosive acetaldehyde liquid, improving work safety, and the reflux liquid flow data collected by the flow sensor in real time is fed back to the control system, forming a complete reflux process data record. Enterprises can deeply understand the rectifying column operation law by analyzing these data, optimize the reflux process parameters, provide data support for process improvement and equipment maintenance, and realize fine and scientific production management.

[0103] The refluxed acetaldehyde is qualified, and the qualified acetaldehyde is collected and stored, including:

[0104] The refluxed acetaldehyde is preliminarily analyzed by an infrared spectrometer, the preliminary analysis is to identify the specific spectral absorption peak of the acetaldehyde molecule, to judge whether the purity requirement is met, the ion impurity content in the acetaldehyde is monitored in real time by a conductivity meter, and the water content in the acetaldehyde is detected by a water content detector;

[0105] After the preliminary analysis is completed, secondary analysis is performed, the secondary analysis is to detect high-boiling-point organic impurities by a high-performance liquid chromatograph, to detect trace metal element impurities by an atomic absorption spectrometer, and to perform physical property detection;

[0106] The primary analysis and secondary analysis results are compared and evaluated with standard analysis data;

[0107] According to the comparison and evaluation results, the qualified acetaldehyde is transported to the finished product collection area through a pipeline, wherein the collection area is provided with a plurality of finished product storage tanks, each of which is marked with number, volume, storage time and storage medium information;

[0108] According to the storage requirements, the acetaldehyde in the finished product storage tank is stored in a low-temperature storage tank, the low-temperature storage tank is provided with a heat insulation layer outside and is equipped with a cooling system to maintain a low-temperature environment in the tank, the low-temperature environment temperature is 0-5℃, and a pressure sensor and a liquid level sensor are installed on the top of the storage tank;

[0109] Finally, the collection and storage of qualified acetaldehyde are completed.

[0110] Specifically, a variety of detection equipment such as infrared spectrometer and conductivity meter are used to realize the comprehensive analysis of acetaldehyde. The infrared spectrometer can quickly identify the specific spectral absorption peak of acetaldehyde molecule and efficiently complete the purity preliminary screening; the conductivity meter and the moisture meter respectively monitor the ion impurities and the water content in real time to control the acetaldehyde quality from the microscopic level. In the secondary analysis, the high-efficiency liquid chromatograph precisely detects high-boiling-point organic impurities, and the atomic absorption spectrometer captures trace metal elements, and then combined with physical property detection, a complete detection system from molecular structure to impurity composition is formed, which greatly reduces the risk of missed detection of unqualified products. The primary and secondary analysis results are compared and evaluated with standard data to establish a scientific and unified quality judgment standard. This quantitative comparison method avoids the subjectivity of human judgment and ensures that each batch of acetaldehyde meets the quality requirements. Once the detection result deviates from the standard, the production link problem can be traced back in time, the process parameters can be adjusted quickly, and the product quality stability and consistency can be effectively improved. The storage tanks in the finished product collection area are marked with detailed information to facilitate information management and improve the efficiency and accuracy of warehousing operations. The low-temperature storage tank is provided with a heat insulation layer and a cooling system to strictly control the temperature at 0-5℃, effectively inhibit the volatilization and decomposition of acetaldehyde, and ensure the stability of its chemical properties. The pressure sensor and liquid level sensor installed on the top can monitor the state of the storage tank in real time and timely alarm abnormal conditions such as overpressure and liquid level overrun, which builds a safety line for acetaldehyde storage to avoid safety accidents and also reduces material loss and operating costs of enterprises.

[0111] In order to solve the problem that in the prior art, there is no more accurate management and control of the recovery step of residual liquid in the whole acetaldehyde rectification process, resulting in unclear and perfect process of acetaldehyde rectification, please refer to Figure 1 and Figure 2 The embodiment provides the following technical scheme:

[0112] The acetaldehyde rectification process residual liquid recovery method based on Internet of Things remote supervision comprises:

[0113] The process parameter data in the acetaldehyde rectification process is collected, the collected process parameter data is processed and transmitted, the transmitted process parameters are received, and the equipment is regulated according to the received process parameters.

[0114] Specifically, by comprehensively collecting the key parameters such as temperature, pressure, and flow in the acetaldehyde rectification process, the Internet of Things system can monitor the production process for 7*24 hours without interruption. Once the process parameters deviate from the safety threshold, the system will immediately trigger a remote alarm, and the staff can take measures in the first time to avoid safety accidents caused by residual liquid accumulation, abnormal pressure and other problems, effectively reduce the safety risk, ensure the smooth operation of production, and the collected process parameters are processed and transmitted, and the management personnel can receive and analyze the data on the remote terminal. Based on these real-time and accurate data, the residual liquid recovery equipment can be remotely and intelligently regulated, such as optimizing the reflux ratio of the rectification tower, adjusting the speed of the residual liquid delivery pump, etc., to ensure that the residual liquid recovery process is always in the optimal working condition, and improve the residual liquid recovery rate and recovery quality.

[0115] The process parameter data in the acetaldehyde rectification process is collected, including:

[0116] First, the sensors corresponding to each link in the acetaldehyde rectification process are confirmed, including the liquid level sensor, temperature sensor and pressure sensor installed in the raw material storage tank; temperature sensor, pressure sensor, gas flow sensor and flow sensor installed at the inlet and outlet of the rectification tower bottom reboiler; temperature sensor, pressure sensor, liquid level sensor and flow sensor installed at the inlet and outlet of the condenser; flow regulating valve, flow sensor on the reflux pipe, and current and voltage sensors of the reflux pump;

[0117] After the sensor confirmation, the data collection mechanism is customized, including the timing collection mechanism or the event triggered collection mechanism;

[0118] The timing collection mechanism is to set a fixed collection period, send data reading instructions to each sensor in turn according to the preset time interval, and the sensor receives the instruction to collect the real-time monitored parameter data;

[0119] The event triggered collection mechanism is to trigger data collection immediately when a specific event occurs in the process;

[0120] After collection, the process parameter data is obtained.

[0121] Specifically, various sensors are deployed at key links such as raw material storage, rectification, condensation, reflux, etc. to realize all-around collection of parameters such as liquid level, temperature, pressure, flow rate, etc. For example, monitoring the parameters at the inlet and outlet of the rectification tower reboiler can help real-time master the heat transfer and material flow state; collecting the cooling water parameters of the condenser can accurately assess the cooling efficiency and provide comprehensive data support for process control; the fixed-period data acquisition mechanism acquires data at fixed periods to ensure the continuity and integrity of production data, which is suitable for stable monitoring under normal working conditions; the event-triggered mechanism starts data collection immediately when specific events such as abnormal fluctuations (e.g. sudden pressure change, temperature overrun) or equipment start-stop occur, accurately captures key node data, facilitates quick identification of problem sources, improves emergency response speed, and the two acquisition mechanisms complement each other to avoid data omission and delay. The fixed-period data acquisition maintains regular data updates, and the event-triggered mechanism enhances the data capture capability under abnormal working conditions, ensuring that the collected data truly reflects the real-time state of the process and provides accurate and timely decision-making basis for the remote monitoring system. Massive real-time data combined with machine learning algorithms can deeply analyze the equipment operation rules and build process optimization models and fault prediction models. For example, by training an abnormality recognition model based on historical data, equipment failure or process fluctuation risks can be warned in advance, reducing unplanned downtime; based on data feedback to optimize parameter settings, the efficiency of acetaldehyde rectification and the stability of product quality can be improved; automated data collection replaces manual inspection and recording, reducing labor input and avoiding human operation errors; operators do not need to frequently enter dangerous areas, reducing the risk of contacting flammable and explosive substances. At the same time, the system automatically stores data, facilitating production process tracing and quality auditing, and meeting the requirements of industry safety supervision.

[0122] The collected process parameter data is subjected to data processing and transmission, including:

[0123] The collected process parameter data is first subjected to data integration, and the parameter data set is obtained after data integration is completed;

[0124] The parameter data set is subjected to data cleaning, which is abnormal value processing, repeated value removal and missing value supplementation;

[0125] After data cleaning, the data is subjected to data standardization processing;

[0126] The data subjected to data standardization processing is transmitted to the control center, and the data is automatically selected to transmit through the transmission channel with the fastest transmission speed when transmitted;

[0127] Among them, the transmission amount of the data subjected to data standardization processing is first confirmed, the number of transmission channels is not less than four, and the channel residual capacity of each transmission channel is monitored in real time;

[0128] The transmission channel with a data transmission amount less than the channel residual capacity is selected as the final transmission channel of the data.

[0129] Specifically, the data quality is improved in all aspects through data integration, cleaning and standardization. The scattered process parameter data is integrated to form a complete parameter data set. The data cleaning removes outliers and repeated values, and supplements missing values, effectively avoiding the interference of false data on subsequent analysis and equipment control. The standardization process unifies the data format and range, facilitating data comparison and analysis, and laying a solid foundation for scientific decision-making based on data. The transmission process automatically selects the channel with the fastest transmission speed, and dynamically matches according to the data transmission volume and channel remaining capacity, significantly improving the data transmission efficiency. Not less than four transmission channels provide a variety of choices, real-time monitoring of channel remaining capacity ensures that the selected channel can carry the data transmission volume and complete the transmission at the fastest speed, avoiding data congestion and transmission delay, so that the control center can obtain the latest process parameter data in time, quickly respond to production needs, and real-time monitor the remaining capacity of each transmission channel. Selecting a channel with a data transmission volume less than the channel remaining capacity as the final transmission channel can effectively prevent data loss or transmission interruption caused by channel overload. The multi-channel backup mechanism also provides redundancy for data transmission. Even if a channel fails, the system can quickly switch to other available channels to ensure the continuity and stability of data transmission and the reliable operation of the acetaldehyde rectification process remote monitoring system.

[0130] According to the received process parameters, the equipment is controlled, including:

[0131] The control center receives the transmitted process parameter data, judges the received process parameter data for abnormalities, and selects abnormal parameter data in the process parameter data according to the judgment result;

[0132] The abnormal reasons of the abnormal parameter data are analyzed;

[0133] According to the correlation analysis result, the control instruction is generated, and finally the generated control instruction is corresponding to the process equipment;

[0134] After the corresponding is completed, the instruction is issued, and the process equipment adjusts the equipment according to the issued instruction.

[0135] Specifically, after receiving the process parameter data, the control center immediately conducts abnormality judgment, can quickly identify parameters exceeding the normal range, and lock potential risks in the production link in the first time. Through screening of abnormal parameter data, the problem is prevented from being magnified, and the safety hidden danger is killed in the embryonic state. At the same time, the abnormal reason is associated and analyzed, the fault source can be accurately located, such as equipment failure, operation error or raw material fluctuation, etc., which provides a clear direction for subsequent processing, greatly improves the risk prevention and control efficiency, generates control instructions according to the correlation analysis results of abnormal reasons, ensures that the instructions have strong pertinence. Whether it is to adjust the equipment operation parameter or to change the process flow, it can accurately adapt to the abnormal situation and avoid blind control to cause secondary influence on production. The accurate correspondence between the instruction and the process equipment further ensures the accuracy of the control operation, so that the equipment adjustment can effectively solve the problem and restore the normal operation of the production, guarantee the stable and efficient acetaldehyde rectification process. From data reception to abnormality judgment, to instruction generation, issuance and equipment adjustment, a complete closed-loop management process is formed. This mode reduces manual intervention and the lag of information transmission, makes the equipment control more timely and efficient. The equipment can quickly respond to the instruction for adjustment, shorten the fault handling time, reduce the loss caused by production interruption, thereby significantly improving the overall production efficiency and reducing the production cost.

[0136] It should be noted that, in this text, relational terms such as first and second are used merely to distinguish one entity or action from another, without necessarily requiring or implying any such actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variant thereof are intended to cover non-exclusive inclusions, so that a process, method, article, or apparatus that includes a list of elements does not only include those elements, but also includes other elements not explicitly listed, or inherent to such process, method, article, or apparatus.

[0137] Although the embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present application.

Claims

1. An acetaldehyde distillation process based on IoT remote monitoring, characterized in that, include: Acetaldehyde feedstock is fed into a distillation column, where it undergoes a distillation process. After distillation, the high-temperature acetaldehyde vapor rising from the top of the column is cooled and liquefied. The cooled and liquefied acetaldehyde liquid is then refluxed back into the distillation column. Finally, the refluxed acetaldehyde is tested for compliance, and the qualified acetaldehyde is collected and stored.

2. The acetaldehyde distillation process based on IoT remote monitoring according to claim 1, characterized in that, The process of feeding acetaldehyde into the distillation column includes: Acetaldehyde is produced from a mixture of raw materials. The mixture is piped into a storage tank, which is equipped with a level sensor to monitor the level of the mixture in real time. When the liquid level of the mixed raw materials falls below the set minimum threshold, an alarm is automatically triggered, prompting the user to replenish the raw materials. The delivery pump draws the mixed raw materials from the raw material storage tank. The flow rate of the delivery pump is controlled by a flow regulating valve, which forms a closed-loop control with the flow sensor. After the mixed raw materials are drawn from the raw material storage tank, they pass through a filter to remove impurities from the mixed raw materials; After filtration, the solution is piped to a distillation column.

3. The acetaldehyde distillation process based on IoT remote monitoring according to claim 1, characterized in that, The raw materials in the distillation column are subjected to a distillation process, including: A reboiler is installed at the bottom of the distillation column. The reboiler is heated by steam, which vaporizes part of the mixed feed in the bottom of the column. The steam generated after the partial vaporization of the mixed feed rises along the trays one by one. The distillation column is equipped with multiple layers of trays, and each tray is equipped with a gas-liquid contact device. On each tray, the steam exchanges heat and mass with the liquid flowing down from above. The low-boiling-point acetaldehyde component continuously vaporizes and rises, while the high-boiling-point heavy components continuously condense and flow back to the bottom of the tray. Finally, the mixed raw materials are purified by distillation.

4. The acetaldehyde distillation process based on IoT remote monitoring according to claim 1, characterized in that, The high-temperature acetaldehyde vapor rising from the top of the distillation column is cooled and liquefied, including: Acetaldehyde vapor discharged from the top of the distillation column enters the condenser. Temperature sensors and flow sensors are installed at both the inlet and outlet of the cooling water in the condenser. The temperature sensors monitor the temperature of the cooling water entering and leaving the condenser in real time, while the flow sensors precisely control the flow rate of the cooling water. The condenser uses a shell-and-tube heat exchanger. The internal structure of the condenser contains multiple heat exchange tubes. High-temperature acetaldehyde vapor flows in the tube side, and cooling water flows in the shell side, exchanging heat through the tube walls. Cooling water enters from the bottom of the condenser and flows from bottom to top along the shell side, forming a counter-current heat exchange with the high-temperature acetaldehyde vapor flowing from top to bottom in the tube side. When the temperature drops below the boiling point of acetaldehyde, the vapor begins to liquefy, changing from a gaseous state to a liquid state; Among them, a gas-liquid separator is installed at the outlet of the condenser. The gas-liquid separator is used to separate the small amount of acetaldehyde vapor that is not completely liquefied from the acetaldehyde liquid that has been liquefied. Unliquefied vapor at the top of the gas-liquid separator is returned to the distillation column through pipelines for further distillation, ultimately completing the cooling and liquefaction process.

5. The acetaldehyde distillation process based on IoT remote monitoring according to claim 1, characterized in that, The acetaldehyde liquid, after cooling and liquefaction, is refluxed back into the distillation column for reflux treatment, including: After liquefaction, the liquefied acetaldehyde liquid collects at the bottom of the gas-liquid separator and flows into the return buffer tank through the discharge pipe. A reflux pump is installed on the outlet pipe of the reflux buffer tank, and the control system sets the start-up parameters of the reflux pump according to the operating status of the distillation column. After the reflux pump starts, the high-speed rotation of the impeller generates centrifugal force, which draws the acetaldehyde liquid out of the reflux buffer tank and forces it into the reflux pipeline. A flow regulating valve and a flow sensor are installed on the return pipeline. The flow regulating valve and the flow sensor form a closed-loop control circuit. The flow sensor monitors the return liquid flow rate in real time and feeds the data back to the control system. Finally, the reflux treatment of the acetaldehyde liquid was completed.

6. The acetaldehyde distillation process based on IoT remote monitoring according to claim 1, characterized in that, The acetaldehyde after refluxing is subjected to a qualification test, and the qualified acetaldehyde is collected and stored, including: The refluxed acetaldehyde was preliminarily analyzed using an infrared spectrometer to identify specific spectral absorption peaks of the acetaldehyde molecule and determine whether the purity requirements were met. The ionic impurity content in the acetaldehyde was monitored in real time using a conductivity meter, and the moisture content in the acetaldehyde was detected using a moisture analyzer. After the preliminary analysis, a secondary analysis was conducted, which involved using high-performance liquid chromatography to detect high-boiling-point organic impurities, using atomic absorption spectrometry to detect trace metal element impurities, and performing physical property analysis. The results of the preliminary and secondary analyses were compared and evaluated with the standard analysis data; Based on the comparison and evaluation results, qualified acetaldehyde will be transported to the finished product collection area through pipelines. The collection area is equipped with multiple finished product storage tanks, each of which is labeled with its number, volume, storage time and storage medium information. Acetaldehyde from the finished product storage tank is stored in a cryogenic storage tank. The cryogenic storage tank is equipped with an external heat insulation layer and a cooling system to maintain the low temperature environment inside the tank. The low temperature environment temperature is 0℃-5℃. Pressure sensors and liquid level sensors are installed on the top of the storage tank. Finally, the collection and storage of qualified acetaldehyde were completed.

7. A method for residual liquid recovery in an acetaldehyde distillation process based on IoT remote monitoring, applied in the acetaldehyde distillation process based on IoT remote monitoring as described in any one of claims 1-6, characterized in that, include: The process parameter data of the acetaldehyde distillation process are collected, processed and transmitted, and the transmitted process parameters are received. The equipment is then adjusted according to the received process parameters.

8. The method for residual liquid recovery in acetaldehyde distillation process based on IoT remote monitoring according to claim 7, characterized in that, Process parameter data for the acetaldehyde distillation process were collected, including: First, identify the sensors corresponding to each step in the acetaldehyde distillation process, including the level sensor, temperature sensor, and pressure sensor installed in the raw material storage tank; the temperature sensor, pressure sensor, gas flow sensor, and flow sensor installed at the inlet and outlet of the reboiler at the bottom of the distillation column; the temperature sensor, pressure sensor, level sensor, and flow sensor installed at the cooling water inlet and outlet of the condenser; the flow regulating valve and flow sensor on the reflux pipeline; and the current and voltage sensors of the reflux pump. Once the sensor is confirmed, the data acquisition mechanism is customized, which may include a timed acquisition mechanism or an event-triggered acquisition mechanism. The timed acquisition mechanism sets a fixed acquisition cycle and sends data reading commands to each sensor sequentially according to a preset time interval. After receiving the command, the sensor will collect the parameter data monitored in real time. The event-triggered acquisition mechanism triggers data acquisition immediately when a specific event occurs during the process. After the data collection is completed, process parameter data is obtained.

9. The method for residual liquid recovery in acetaldehyde distillation process based on IoT remote monitoring according to claim 7, characterized in that, The collected process parameter data will be processed and transmitted, including: The collected process parameter data is first integrated to obtain the parameter dataset. The parameter dataset is cleaned by handling outliers, removing duplicates, and filling in missing values. Data standardization is performed after data cleaning. The standardized data is transmitted to the control center, and the fastest transmission channel is automatically selected during data transmission. First, the amount of data transmitted after data standardization is confirmed, the number of transmission channels is no less than four, and the remaining capacity of each transmission channel is monitored in real time. The transmission channel with a data transmission volume less than the remaining channel capacity is selected as the final transmission channel for the data.

10. The method for residual liquid recovery in acetaldehyde distillation process based on IoT remote monitoring according to claim 7, characterized in that, The equipment is adjusted according to the received process parameters, including: The control center receives the transmitted process parameter data, performs anomaly detection on the received process parameter data, and filters out abnormal parameter data from the process parameter data based on the detection results. Perform correlation analysis on the causes of anomalies in abnormal parameter data; Control commands are generated based on the correlation analysis results, and finally, the generated control commands are mapped to the process equipment. Once the alignment is complete, instructions are issued, and the process equipment adjusts accordingly.

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