DCS control system for chemical reaction

Abstract

The application discloses a DCS control system for chemical reaction, and relates to the technical field of DCS control systems, which comprises a management terminal module, an information processing module, a control module and a real-time monitoring module. The management terminal module is in communication connection with the information processing module. The information processing module is in communication connection with the control module and the real-time monitoring module. The real-time monitoring module comprises a plurality of liquid level sensors and a plurality of concentration-PH integrated sensors. The liquid level sensors of the real-time monitoring module are always in a monitoring state. The start and stop of the concentration sensor and the PH integrated sensor are controlled through linkage between the plurality of liquid level sensors. The application can accurately inject a retarder to control the start and stop of the reaction in the reaction kettle when a large number of difference values are generated in the concentration space difference value of the reaction kettle and 1 minute exists, thereby increasing the safety of the application.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of DCS control systems, in particular to a DCS control system for chemical reactions. BACKGROUND

[0002] DCS (Distributed Control System) is the core system for real-time monitoring and automatic control in chemical production. It realizes precise adjustment of process parameters such as temperature, pressure and flow by networking field instruments, PLCs and other devices through a decentralized control and centralized management architecture. Typical functions include PID loop control, interlock protection, data acquisition and trend recording. Compared with traditional instrument control, DCS has the advantages of high reliability (redundant design), flexible configuration (graphical programming) and remote operation, which can significantly improve production safety and efficiency, for example, in reaction kettle temperature control, the steam valve opening can be automatically adjusted to avoid the risk of manual intervention. The system is usually composed of an engineer station, an operator station and a control station, supporting Modbus, OPC and other communication protocols.

[0003] However, the current DCS control system lacks a processing procedure for the unreacted condition inside the reaction kettle. For example, if the stirring device stops working, the different solutions at various positions inside the reaction kettle cannot be mixed quickly, and the long-stagnant solution is prone to dangerous conditions. SUMMARY

[0004] To solve the problem of lacking a processing procedure for the unreacted condition inside the reaction kettle in the background art, the purpose of the present application is to provide a DCS control system for chemical reactions.

[0005] To achieve the above purpose, the present application provides the following technical scheme: a DCS control system for chemical reactions, comprising a management terminal module, an information processing module, a control module and a real-time monitoring module, the management terminal module being in communication connection with the information processing module, and the information processing module being in communication connection with the control module and the real-time monitoring module.

[0006] The real-time monitoring module comprises a plurality of liquid level sensors and a plurality of concentration-PH integrated sensors.

[0007] The liquid level sensors of the real-time monitoring module are always in a monitoring state, and the start and stop of the concentration sensors and the PH integrated sensors are controlled through the linkage between the multiple liquid level sensors.

[0008] First, the start and stop of the concentration-PH integrated sensors are controlled according to the state of the liquid level sensors, and the linkage control condition is:

[0009] (1);

[0010] In the above formula (1), Sensor activation state (1 for enable, 0 for disable), Real-time liquid level in the reactor, Minimum working liquid level, Safety buffer value;

[0011] After the concentration-Ph integrated sensor is turned on, the concentration spatial difference in the reaction chamber is detected by the concentration-Ph integrated sensor distributed in the reaction chamber, and the concentration spatial difference monitoring model is:

[0012] (2);

[0013] In the above formula (2), the concentration spatial difference at time t (dimensionless percentage) is The average value of all effective concentration sensors at time t is The maximum concentration value of all effective sensors at time t is The minimum concentration value of all effective sensors at time t is The measurement value of the i-th concentration sensor at time t is

[0014] Preferably, the calculation formula of the average concentration is:

[0015] (3);

[0016] In the above formula (3), N is the current number of effective sensors (according to the activated sensor in the above formula (1)).

[0017] Preferably, the management terminal module includes a sub-terminal management control unit, a data recording unit, and an information printing unit.

[0018] The sub-terminal management control unit realizes centralized monitoring and configuration management of distributed sub-terminals, supports remote parameter setting, authority hierarchical control, and device state diagnosis, and ensures the stability and consistency of multi-terminal collaborative operation.

[0019] The data recording unit provides full-cycle process data archiving function, stores sensor readings, operation instructions and system events with time stamp index, supports high compression ratio storage and breakpoint resume mechanism, and meets the industrial-level data traceability demand.

[0020] The information printing unit integrates label printing, report output and alarm log hard copy capabilities, is compatible with thermal / laser printing protocols, can customize output templates and support barcode binding of key process parameters.

[0021] Preferably, the information processing module includes a visual graph unit, a system configuration unit, a report generation unit, a flowchart generation unit, and a processor unit. ​

[0022] Visual graphics unit: Based on a vector engine, it dynamically renders device topology diagrams and real-time data dashboards, supports multi-layer overlay display, zoom and roaming, and key parameter pop-up prompts, providing an immersive monitoring experience;

[0023] System configuration unit: Provides a drag-and-drop engineering development environment, supports control logic diagram editing, device binding and I / O point configuration, and has version management and offline simulation verification functions;

[0024] Report generation unit: Built-in configurable report engine, supports automatic generation of production statistics, energy efficiency analysis and quality reports by shift / day / month, and provides ODBC standard data interface;

[0025] Flowchart generation unit: Intelligently analyzes the relationship between process pipelines and equipment, generates P&ID standard flow charts with one click, and supports dynamic data embedding and equipment status color display;

[0026] Processor unit: Equipped with a real-time multitasking operating system, it performs data fusion calculations, control algorithm scheduling, and communication protocol parsing, providing millisecond-level event response capabilities.

[0027] Preferably, the control module includes several controller units (motor, valve, switch).

[0028] Preferably, the liquid level sensor is vertically distributed inside the reactor, and the concentration-Ph integrated sensor is distributed in a multi-layered ring shape inside the reactor.

[0029] Preferably, to prevent instantaneous fluctuations from triggering uneven material mixing, a time difference variation persistence function is set:

[0030] (4);

[0031] The triggering condition for the above formula (4) is: ≥ ( (the maximum allowable duration of the difference).

[0032] In the above formula (4), The cumulative duration for which the concentration difference exceeds a threshold. The concentration difference threshold, For the first time the concentration difference exceeds the threshold The point in time, Current time, For indicator functions, when the condition < The value is 1 if the condition is met, and 0 otherwise.

[0033] The time length of whether the concentration difference exceeds the threshold value can be calculated by formula (4), and the emergency measures are triggered after the high difference state lasts for a certain time to avoid misoperation caused by the time wave.

[0034] Preferably, when the emergency measures are triggered by the unexpected situation occurring in the reaction kettle, the chemical liquid in the reaction kettle needs to be treated, and the injection type control of the retarder is performed by the pH sensor at this time, and the function is represented as:

[0035] (5);

[0036] In the above formula (5), is the median of all effective PH sensor measurement values at time t, is the lower limit of the PH safety range, is the upper limit of the PH safety range;

[0037] The median and are used.

[0038] Preferably, according to the solution state in the reaction kettle detected by the pH sensor, the injection of the retarder is determined, and the dynamic injection model of the retarder is as follows:

[0039] (6);

[0040] In the above formula (6), is the retarder injection rate at time t, is the basic injection rate, is the adjustment gain factor (for example, 0.5), is the target pH value, is the maximum allowed PH deviation.

[0041] In the above formula (6), .

[0042] Compared with the prior art, the beneficial effects of the present application are as follows:

[0043] 1、The real-time monitoring module of the present application includes a plurality of liquid level sensors arranged in the reaction kettle, which are used to monitor the liquid level in the reaction kettle, and a plurality of concentration-PH sensors, the concentration sensors are arranged in the reaction kettle (the start and stop of the concentration sensors are controlled according to the monitoring results of the liquid level sensors), the data monitored by the concentration sensors in each time period are monitored, and the monitoring results are stored, and a plurality of concentration-PH sensors are arranged close to the concentration sensors one by one, when the concentration difference value of a plurality of concentration sensors produces a large number of difference values and exists for 1 minute, the reaction in the reaction kettle is controlled to start and stop, thereby increasing the safety of the present application.

[0044] 2, The application is based on the concentration-PH integrated sensor to obtain the concentration and PH synchronous data of each spatial position in the reaction kettle, and through real-time analysis of the reaction state difference of different coordinate points, a targeted injection strategy is dynamically generated: the best retarder type is automatically matched according to the local concentration abnormal value, the injection rate parameter is calculated according to the PH mutation gradient, and a spatial differentiated injection scheme is formed. The control mechanism makes the retarder accurately delivered to the reaction hotspot area, realizes the directional inhibition of millisecond-level response speed, ensures the rapid and accurate termination of the chemical reaction process in the reaction kettle when the precursors of out-of-control are monitored, effectively blocks the chain reaction transmission, thereby suppresses the thermal runaway risk in the embryonic stage, and greatly improves the intrinsic safety protection level.

[0045] The parts not involved in the device are the same as or can be realized by the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 It is a structure block diagram of a DCS control system for a chemical reaction of the application.

[0047] Figure 2 It is a flowchart of a DCS control system for a chemical reaction of the application.

[0048] Figure 3 It is an internal situation diagram of a reaction kettle of a DCS control system for a chemical reaction of the application Figure 1 .

[0049] Figure 4 It is an internal situation diagram of a reaction kettle of a DCS control system for a chemical reaction of the application Figure 2 . DETAILED DESCRIPTION

[0050] In order to make the technical means, creative features, purposes and effects realized by the application easy to understand, the application will be further described below in combination with specific embodiments.

[0051] As shown in Figures 1-4 , the application provides a DCS control system for a chemical reaction, which comprises a management terminal module, an information processing module, a control module and a real-time monitoring module, the management terminal module is in communication connection with the information processing module, and the information processing module is in communication connection with the control module and the real-time monitoring module.

[0052] The management terminal module comprises a sub-terminal management control unit, a data recording unit and an information printing unit.

[0053] The sub-terminal management control unit is the core hub of the distributed architecture, which realizes the whole life cycle management of the multi-level sub-terminal in the factory area. Through the OPC UA protocol, a secure communication channel is established, which has three core functions of real-time monitoring of terminal state, remote firmware upgrade, and dynamic allocation of access rights. It supports geographic information system (GIS) mapping to display the terminal distribution topology. When detecting that the terminal is offline or the data is abnormal, it automatically triggers a hierarchical alarm and starts the redundancy switching mechanism. The built-in terminal health assessment algorithm generates device maintenance warnings based on 12 indicators such as runtime, communication quality, and processing delay, significantly improving system availability.

[0054] Data recording unit: Build an industrial big data storage hub, adopt time series database (TSDB) and relational database (RDBMS) dual-engine architecture, support millisecond-level timestamp tagging and metadata association storage. With intelligent data compression function, the storage space is reduced by 70% through improved rotating door algorithm. Innovatively integrate data integrity verification mechanism, use CRC32+MD5 double check code to ensure ten-year data lossless traceability. Support multi-dimensional combined query by process batch, equipment number, alarm level, etc., meet the requirements of FDA 21 CFR Part 11 electronic record specification;

[0055] Information printing unit: Build a full-scene hard copy output system, support seamless access of multiple printing devices such as thermal, laser, and needle type. Develop intelligent template engine to realize automatic layout of alarm records, dynamic generation of quality reports, and batch printing of equipment labels, etc. The unique barcode fusion technology encodes process parameters (such as batch number, temperature curve, operator ID) into QR / Data Matrix composite barcode for easy mobile scanning and tracing. Equipped with a smart printer task scheduler that automatically switches to a backup printer and notifies maintenance personnel when it detects a lack of carbon tape or paper jam, ensuring that critical information is not lost.

[0056] The information processing module includes a visualization unit, a system configuration unit, a report generation unit, a flowchart generation unit, and a processor unit.

[0057] Visualization unit: A 3D visualization platform based on WebGL technology, which realizes immersive monitoring of device running status. Supports multi-level LOD (level of detail) rendering, from factory panorama to valve actuator details without scaling. Innovatively develops "data lens" function, which displays real-time parameters, historical trend curves and maintenance records of the device when the mouse hovers over it. Built-in AR augmented reality interface, combined with smart glasses to realize 3D labeling of device fault points. Provides 22 industrial standard symbol libraries, you can customize temperature cloud map, flow vector field and other professional visualization effects;

[0058] System configuration unit: Adopt graphical configuration development environment (IDE), support five programming languages of IEC 61131-3 standard. With intelligent device discovery function, automatically identify fieldbus devices and generate electronic device description (EDD). Provide control logic simulation test platform, can simulate 200+ kinds of abnormal working conditions to verify the robustness of the program. Version management subsystem supports Git workflow, realizes incremental backup, difference comparison and one-key rollback of configuration project. The unique "digital twin" compilation technology synchronously generates PLC code and three-dimensional simulation model of control logic.

[0059] Report generation unit: Build an enterprise-level report center, integrate SPC (statistical process control) analysis engine. Support custom SQL query builder, can extract data across historical database, real-time database, MES system. Provide 28 kinds of professional chart templates such as X-Bar R control chart and Pareto analysis, automatically calculate CPK, OEE and other key indicators. Develop intelligent report scheduler, support event triggering (such as batch end), periodic triggering (such as shift handover) or manual instruction to generate PDF / Excel format report, and automatically distribute through email;

[0060] Flowchart generation unit: P&ID automatic generation system based on artificial intelligence, automatically layout pipeline direction through device relationship graph analysis. Support ISA S5.1 standard symbol library, can identify 500+ kinds of industrial device types. Innovatively develop "dynamic data binding" function, directly superimpose real-time pressure, temperature and other parameter display on flowchart. Provide three-dimensional pipeline collision detection, automatically alarm when new pipeline conflicts with existing equipment. Integrated with CMMS system, click on the device icon to directly call maintenance work order history;

[0061] Processor unit: Equipped with multi-core real-time processing architecture, uses Xenomai real-time Linux kernel to ensure microsecond-level response. Build a three-layer data processing pipeline: the first layer performs sensor data filtering and outlier rejection; the second layer executes model predictive control (MPC) algorithm calculation; the third layer coordinates OPC DA / UA, Modbus TCP, PROFINET and other industrial protocol communication.

[0062] The control module includes several controller units (motors, valves, switches), the pump station uses vector control and direct torque control dual control mode, the valve uses Athenian ceramic technology to realize higher switching control precision, the switch uses double-way electric control valve, through which the fluid can be controlled more accurately.

[0063] The real-time monitoring module comprises a plurality of liquid level sensors and a plurality of concentration-PH integrated sensors. The concentration-PH integrated sensor adopts a frame to install a concentration sensor and a PH sensor. The two sensors are closely arranged. This arrangement can make the data detected by the two sensors more consistent and can adapt to better linkage effect.

[0064] The liquid level sensor of the real-time monitoring module is always in a monitoring state. Through linkage between the plurality of liquid level sensors, the concentration sensor and the PH integrated sensor are controlled to start and stop. The liquid level sensor is vertically distributed in the reaction kettle. The concentration-PH integrated sensor is distributed in a plurality of layers in the reaction kettle in a ring shape (see Figure 3 and Figure 4 ).

[0065] First, the concentration-PH integrated sensor is controlled to start and stop according to the state of the liquid level sensor. The linkage control condition is as follows:

[0066] (1);

[0067] In the above formula (1), is the sensor activation state (1 for starting and 0 for prohibiting), is the real-time liquid level in the reaction kettle, is the minimum working liquid level, is a safety buffer value;

[0068] After the concentration-PH integrated sensor is started, the concentration-PH integrated sensor distributed in the reaction degree detects the concentration spatial difference in the reaction degree. The concentration spatial difference monitoring model is as follows:

[0069] (2);

[0070] In the above formula (2), is the concentration spatial difference at time t (dimensionless percentage), is the average value of all effective concentration sensors at time t, is the maximum concentration value of all effective sensors at time t, is the minimum concentration value of all effective sensors at time t, is the measurement value of the i-th concentration sensor at time t;

[0071] The calculation formula of the average concentration is as follows:

[0072] (3);

[0073] In the above formula (3), N is the number of current effective sensors (according to the activation sensor in the above formula (1)).

[0074] To prevent the possibility of transient fluctuations triggering material mixing uneven, set time difference variation duration function:

[0075] (4);

[0076] The trigger condition of the above formula (4) is: ≥ ( The maximum allowable difference time);

[0077] In the above formula (4), is the cumulative duration of concentration difference exceeding the threshold value, is the concentration difference threshold value, is the time point when the concentration difference first exceeds the threshold value , the current time, is the indicator function, which is 1 when the condition < is 0 otherwise;

[0078] Through formula (4), the length of time when the concentration difference exceeds the threshold value can be calculated. When the high difference state lasts for a certain time, the emergency measures are triggered to avoid false operation caused by the fluctuation of time.

[0079] When the emergency measures are triggered by the unexpected situation in the reaction kettle calculated by formula (4), the chemical liquid in the reaction kettle needs to be treated. At this time, the injection type control of the retarder is carried out through the pH sensor, and its function is represented as:

[0080] (5);

[0081] In the above formula (5), is the median of all valid PH sensor measurement values at t, is the lower limit of PH safety range, is the upper limit of PH safety range;

[0082] The median and.

[0083] According to the solution state in the reaction kettle detected by the pH sensor, the injection of the retarder is determined, and the dynamic injection model of the retarder is as follows:

[0084] (6);

[0085] In the above formula (6), is the retarder injection rate at t, is the basic injection rate, is the adjustment gain factor (for example, 0.5), is the target pH value,​ Maximum allowable PH deviation.

[0086] In the above formula (6), .

[0087] It should be noted that the use steps of the present application are:

[0088] First, the liquid level state in the reactor is monitored by the liquid level sensor, the liquid level state is detected by formula (1), and whether to start the concentration-PH integrated sensor is determined according to the result of formula (1);

[0089] Second, if the result obtained according to formula (1) is normal, continue to run, if the result obtained according to formula (1) is abnormal, start the concentration-PH integrated sensor to monitor the concentration and pH value of each position in the reactor;

[0090] Third, the space concentration difference degree is determined by formula (2), and the time when the space concentration difference degree is exceeded is determined by formula (4), if the time when the space concentration difference degree is exceeded TS does not exceed the predetermined value, return to the first step, if the time when the space concentration difference degree is exceeded TS exceeds the predetermined value, select the type of retarder according to the solution PH of each position in the reactor (this step selects the retarder by formula 5);

[0091] Fourth, the best injection rate is calculated according to the solution PH of each position in the reactor;

[0092] Fifth, the accurate retarder injection is carried out according to the data obtained in the last step, so that the solution in the reactor is neutralized to prevent dangerous situation from occurring again, and the alarm is started.

[0093] In this document, the terms "first" and "second" and the like 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 variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements recited, but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0094] The above shows and describes the basic principles and main features of the present application and the advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A DCS control system for chemical process applications, characterized by, The management terminal module, the information processing module, the control module, and the real-time monitoring module are connected in communication, the information processing module is connected in communication with the control module and the real-time monitoring module, and the real-time monitoring module includes a plurality of liquid level sensors and a plurality of concentration-PH integrated sensors. The liquid level sensors of the real-time monitoring module are always in a monitoring state, and the concentration sensors and the PH integrated sensors are started and stopped through linkage between the plurality of liquid level sensors. First, the concentration-PH integrated sensor is controlled according to the state of the liquid level sensor, and the linkage control condition is that: After the concentration-PH integrated sensor is started, the concentration-PH integrated sensors distributed in the reaction chamber are used to detect the concentration spatial difference in the reaction chamber, and the concentration spatial difference monitoring model is: （1）； In the above formula (1), is the sensor activation state, is the real-time liquid level in the reactor, is the minimum working liquid level, is the safety buffer value; In order to prevent the possibility of instantaneous fluctuation triggering uneven material mixing, a time difference variation duration function is set: （2）； In the above equation (2), is the concentration spatial diversity at time t, is the average value of all concentration-Ph integrated sensors at time t, is the maximum concentration value of all concentration-Ph integrated sensors at time t, is the minimum concentration value of all concentration-Ph integrated sensors at time t, is the measurement value of the i-th concentration-Ph integrated sensor at time t; The time length of whether the concentration difference exceeds the threshold value is calculated through formula (4), and when the high difference state lasts for a certain time, an emergency measure is triggered to avoid misoperation caused by instantaneous fluctuation. （4）； The trigger condition of the above formula (4) is: ≥ , is the maximum allowed sustained difference time; In the above equation (4), is the accumulated duration of concentration difference exceeding the threshold value, is the concentration difference threshold value, is the time point at which the concentration difference first exceeds the threshold value is the current time, is the current time, is an indicator function that is 1 when the condition < 0 holds, and 0 otherwise; The calculation formula of the average concentration is:

2. The DCS control system for a chemical process according to claim 1, wherein, In the above formula (3), （3）； N is the current effective sensor number, which is calculated according to the activated sensor in the above formula (1). The management terminal module includes a sub-terminal management control unit, a data recording unit, and an information printing unit.

3. The DCS control system for chemical process according to claim 1, wherein, The sub-terminal management control unit realizes centralized monitoring and configuration management of distributed sub-terminals, supports remote parameter setting, authority hierarchical control, and equipment state diagnosis, and ensures the stability and consistency of the collaborative operation of multiple terminals. The data recording unit provides full-cycle process data archiving functions, stores sensor readings, operation instructions, and system events with time stamp indexing, supports high compression ratio storage and breakpoint resume mechanism, and meets the industrial-level data traceability requirements. The information printing unit integrates label printing, report output, and alarm log hard copy capabilities, supports thermal / laser printing protocols, can customize output templates, and supports barcode binding of key process parameters. The information processing module includes a visualization graphics unit, a system configuration unit, a report generation unit, a flowchart generation unit, and a processor unit.

4. The DCS control system for chemical process according to claim 1, characterized in that, The visualization graphics unit dynamically renders device topology graphs and real-time data dashboards based on a vector engine, supports multi-layer overlay display, zooming and roaming, and key parameter pop-up prompts, and provides an immersive monitoring experience. The system configuration unit provides a drag-and-drop engineering development environment, supports control logic diagram editing, device binding, and I / O point configuration, and has version management and offline simulation verification functions. The report generation unit has a built-in configurable report engine, supports automatic generation of production statistics, energy efficiency analysis, and quality reports according to shifts, days, and months, and provides an ODBC standard data interface. The flowchart generation unit intelligently analyzes the association between process pipelines and devices, one-click generates P&ID standard flowcharts, supports dynamic data embedding and device state coloring display. The processor unit is equipped with a real-time multi-task operating system, performs data fusion calculation, control algorithm scheduling, and communication protocol analysis, and provides millisecond-level event response capability. ​ 5. The DCS control system for chemical process according to claim 1, wherein, The control module comprises a plurality of controller units, and the plurality of controller units comprise a motor controller unit, a valve controller unit and a switch controller unit.

6. The DCS control system for a chemical process according to claim 1, wherein, The liquid level sensor is vertically distributed in the reaction kettle, and the concentration-pH integrated sensor is distributed in a multi-layer ring shape in the reaction kettle.

7. The DCS control system for a chemical process according to claim 1, wherein, When an emergency measure is triggered due to an unexpected situation in the reaction kettle, the chemical liquid in the reaction kettle needs to be treated, and at this time, the injection type control of the retarder is performed through the pH sensor, and the function is expressed as: （5）； In the above equation (5), is the median of all concentration-Ph integrated sensor measurements at time t, is the lower limit of the PH safety range, is the upper limit of the PH safety range; The median and the mean are used.

8. The DCS control system for a chemical process according to claim 7, wherein, According to the solution state in the reaction kettle detected by the pH sensor, the injection of the retarder is determined, and the dynamic injection model of the retarder is as follows: （6）； In the above equation (6), is the retarder injection rate at time t, is the base injection rate, is the adjustment gain factor, is the target pH value, is the maximum allowed pH deviation.

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