Control method, device, equipment and medium for partition plate type side mining coarse separation tower

Abstract

The invention provides a control method, device and equipment for a partition plate type side-mining coarse separation tower and a medium. The method comprises the steps that the real-time feeding amount of the coarse separation tower and the real-time temperature of a target detection point are obtained; feedforward control is carried out on the steam flow of the coarse separation tower according to the real-time feeding amount so as to reduce the fluctuation of the upper temperature of the side mining tower, and the feedforward control is a control mode of adjusting the steam flow in advance according to the change of the feeding amount; according to the real-time temperature of the left lower temperature detection point and a corresponding first target control value, the small backflow flow is adjusted based on left lower temperature-small backflow cascade control, so that the temperature fluctuation of the left lower temperature detection point is reduced; and according to the real-time temperature of the tower top temperature detection point, the large reflux flow is subjected to compensatory adjustment, so that the temperature fluctuation of the tower top temperature detection point is reduced. The control precision of the partition plate type side-mining rough separation tower can be improved.

Description

Technical Field

[0001] This invention relates to the field of polycrystalline silicon technology, and in particular to a control method, apparatus, equipment and medium for a partition-type side-extraction coarse separator tower. Background Technology

[0002] In separation processes, baffled coarse separators with side streams are widely used for the initial separation and load distribution of multi-component systems. These separators exhibit significant heat and material coupling within their structure: bottom reboiler steam, top reflux, side stream extraction, and reflux paths interact at different heights and time scales, causing the temperature at multiple monitoring points within the separator to exhibit asynchronous and varying dynamic responses to feed disturbances or load changes.

[0003] Existing control strategies often employ a fixed setpoint centered on a single temperature point, supplemented by conventional PID feedback regulation. For example, a single temperature at the top or bottom of the column is selected as the controlled variable, and the setpoint is maintained by adjusting the reflux valve or steam valve. The controller only outputs a correction value when the temperature deviates from the setpoint. In other words, existing coarse separator control methods rely excessively on a fixed setpoint for a single temperature point and passive feedback regulation, resulting in system response lag, significant regulation oscillations, and difficulty in maintaining coordinated temperature stability across multiple zones under fluctuating operating conditions, ultimately affecting separation efficiency and product quality.

[0004] Therefore, the existing coarse separation tower control method has low control accuracy. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to address the above-mentioned shortcomings of the prior art by providing a control method, device, equipment and medium for a diaphragm-type side-extraction coarse separator, which can improve the control accuracy of the coarse separator.

[0006] In a first aspect, the present invention provides a control method for a diaphragm-type side-extraction coarse separator, the method comprising:

[0007] The real-time feed rate of the coarse separation column and the real-time temperature of the target detection points are obtained. The target detection points include at least the temperature detection point at the top of the column, the temperature detection point at the lower left side, and the temperature detection point at the upper side sampling point.

[0008] Feedforward control is performed on the steam flow rate of the coarsening tower based on the real-time feed rate to reduce the temperature fluctuation of the upper part of the side sampling. Feedforward control is a control method that adjusts the steam flow rate in advance according to the changes in the feed rate.

[0009] Based on the real-time temperature of the temperature detection point at the lower left and the corresponding first target control value, the small reflux flow rate is adjusted according to the cascade control of the lower left temperature and the small reflux to reduce the temperature fluctuation at the lower left temperature detection point; the small reflux is the liquid flow rate returning from the middle side sampling part of the coarse separator to the left area; the cascade control is a dual-loop control structure that controls the small reflux flow rate with the lower left temperature.

[0010] Based on the real-time temperature at the top temperature monitoring point, the high reflux flow rate is adjusted compensatorily to reduce temperature fluctuations at the top temperature monitoring point; the high reflux is the liquid flow rate returning from the top condenser of the coarse separator to the upper part of the right-side region.

[0011] Secondly, the present invention provides a control device for a diaphragm-type side-harvesting coarse feed tower, the device comprising:

[0012] The acquisition module is used to acquire the real-time feed rate of the coarse separation tower and the real-time temperature of the target detection points. The target detection points include at least: the tower top detection point, the lower left detection point, and the upper side sampling temperature detection point.

[0013] The first control module, connected to the acquisition module, is used to perform feedforward control on the steam flow of the coarse separator based on the real-time feed rate, so as to reduce the temperature fluctuation of the upper part of the side sampling. The feedforward control is a control method that adjusts the steam flow in advance according to the change of the feed rate.

[0014] The second control module, connected to the first control module, is used to adjust the small reflux flow rate based on the real-time temperature of the temperature detection point at the lower left side and the corresponding first target control value, according to the cascade control of the lower left temperature and small reflux, so as to reduce the temperature fluctuation at the lower left temperature detection point; the small reflux is the liquid flow rate returning from the middle side sampling part of the coarse separator to the left area; the cascade control is a dual-loop control structure that controls the small reflux flow rate based on the lower left temperature.

[0015] The third control module, connected to the second control module, is used to make compensatory adjustments to the large reflux flow rate based on the real-time temperature of the top temperature detection point, so as to reduce the temperature fluctuation of the top temperature detection point; the large reflux is the liquid flow rate returning from the top condenser of the coarse fractionation column to the upper part of the right side region.

[0016] Thirdly, the present invention provides an electronic device including a processor, a memory, and a program or instructions stored in the memory and executable on the processor, wherein the program or instructions, when executed by the processor, implement the partition-type side-collection coarse-distillation tower control method as described in the first aspect.

[0017] Fourthly, the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the partition-type side-collection coarse-distillation tower control method described in the first aspect.

[0018] The present invention provides a control method, apparatus, equipment, and medium for a diaphragm-type side-feed coarse separator. By acquiring the real-time feed rate and adjusting the steam flow accordingly, the heating supply is pre-matched to changes in feed, reducing temperature deviation in the upper side-feed section. By acquiring the temperature in the lower left section and comparing it with a first target control value, the small reflux flow rate is adjusted based on the cascade control of the lower left temperature and the small reflux, reducing temperature fluctuations in the lower left section. Furthermore, by acquiring the top temperature and compensating for the large reflux flow rate, fluctuations in the top temperature are suppressed. This multi-detection-point driven coordinated adjustment of steam, small reflux, and large reflux ensures that the temperatures in each key area remain closer to the target state under disturbance and coupling conditions, reducing overall temperature fluctuations within the separator and thus improving the control accuracy of the entire coarse separator. Attached Figure Description

[0019] Figure 1 This is a flowchart of a diaphragm-type side-extraction coarse separator method according to Embodiment 1 of the present invention;

[0020] Figure 2 This is one of the control architecture diagrams for the diaphragm-type side-extraction coarse-distillation tower method of Embodiment 1 of the present invention;

[0021] Figure 3 This is the second control architecture diagram of the diaphragm-type side-extraction coarse-distillation tower method of Embodiment 1 of the present invention;

[0022] Figure 4 This is a schematic diagram of a cascade control according to Embodiment 1 of the present invention;

[0023] Figure 5 This is a schematic diagram of a simulation model of a diaphragm-type side-extraction coarse-distillation tower according to Embodiment 1 of the present invention;

[0024] Figure 6 This is a schematic diagram of the structure of a diaphragm-type side-harvesting coarse separator control device according to Embodiment 2 of the present invention;

[0025] Figure 7 This is a schematic diagram of a device structure according to Embodiment 3 of the present invention.

[0026] The markings in the diagram mean:

[0027] 1. Feed inlet; 2. Steam heating inlet; 3. Small reflux; 4. Lower left detection point; 5. Tower top pressure detection point; 6. First temperature detection point at the top of the tower; 7. Large reflux; 8. Second temperature detection point at the top of the tower; 9. Upper side sampling temperature detection point; 10. Side sampling port liquid level detection point. Detailed Implementation

[0028] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0029] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0030] As the core unit for material separation in the polycrystalline silicon cold hydrogenation process, the coarse separation tower achieves preliminary separation of the mixture (mainly including trichlorosilane, silicon tetrachloride, hydrogen chloride, silicon powder and high-boiling substances) after the cold hydrogenation fluidized bed reaction based on the difference in boiling points of each component through the distillation principle.

[0031] A baffle-type side-draw coarse fractionation column refers to a distillation / absorption separation column device with baffles inside the column and a side-draw structure. It has left / right side regions and side-draw channels, and has conventional units such as top condensation and bottom reboiling.

[0032] Early crude fractionation columns were structurally similar to conventional distillation columns. However, to improve separation efficiency, subsequent technologies developed dual-column structures, combining high-pressure and low-pressure columns. To further optimize energy consumption, an improved design proposed a single-column structure with a central baffle, known as a baffle-type side-collection crude fractionation column. In this structure, the top of the column primarily produces trichlorosilane (purity ≥95%) and a small amount of dichlorosilane (content ≤5%), while the bottom discharges high-boiling-point substances containing silicon powder. Silicon tetrachloride (purity ≥99%) is collected from the lower right side of the baffle, while a small reflux device is added to the upper left side of the baffle.

[0033] Existing control strategies mostly employ a fixed setpoint centered on a single temperature point, supplemented by conventional PID feedback regulation. For example, a single temperature at the top or bottom of the column is selected as the controlled variable, and the setpoint is maintained by adjusting the reflux valve or steam valve. The controller only outputs a correction value when the temperature deviates from the setpoint. This deviation-driven, passive regulation method has the following limitations:

[0034] (1) Lack of feedforward capability: It cannot respond to major disturbances such as changes in feed rate and composition in advance. It usually starts to correct the deviation after the disturbance has entered the tower, which is prone to response lag and large overshoot. (2) Insufficient multi-region coordination: A single measuring point target is difficult to take into account the coordinated stability of the tower top, tower bottom and side line areas. It often causes the convergence of a certain area to have an adverse effect on other areas. (3) Rigid setpoint: The fixed temperature setpoint is difficult to adapt to the continuous changes in feed and load, which leads to the decline of control quality as the operating conditions drift.

[0035] Therefore, existing coarse separator control methods have low control accuracy for diaphragm-type side-mining coarse separators.

[0036] Based on the above-mentioned technical problems, this application provides a control method for a diaphragm-type side-mining coarse separator to improve the control accuracy of the diaphragm-type side-mining coarse separator.

[0037] Example 1:

[0038] This embodiment provides a control method for a diaphragm-type side-extraction coarse separator, which can be used for temperature control of diaphragm-type side-extraction coarse separators in polysilicon production enterprises, thermal power plants, chemical plants, metallurgical enterprises, and large-scale industrial production facilities.

[0039] like Figure 1 As shown, the method includes the following steps S101 to S105:

[0040] S101. Obtain the real-time feed rate of the coarse separator and the real-time temperature of the target detection point.

[0041] The target detection points include at least: a temperature detection point at the top of the tower, a temperature detection point at the lower left side, and a temperature detection point at the upper side sampling point. The temperature detection point at the top of the tower is located in the condensation reflux zone at the top of the tower or in its upper region. The temperature detection point at the lower left side is located at a lower position on the left side of the tower. The temperature detection point at the upper side sampling point is located in the region above the side sampling point.

[0042] The real-time feed rate is the online measurement of the feed flow rate entering the coarsening tower, which is generally obtained through a feed line flow meter and can be either mass flow rate or volumetric flow rate.

[0043] Specifically, the feed rate data of the coarse separator and the temperature data of multiple target detection points (including at least the temperature detection point at the top of the tower, the temperature detection point at the lower left side, and the temperature detection point at the upper side) are continuously and in real time acquired through the on-site data acquisition device.

[0044] S102. Feedforward control of the steam flow rate of the coarse separator is performed based on the real-time feed rate to reduce the temperature fluctuation of the upper part of the side sampling.

[0045] Feedforward control is a control method that adjusts the steam flow rate in advance based on changes in the feed rate. In other words, it adjusts the execution quantity in advance based on real-time changes in disturbance variables to reduce the impact of disturbances. The steam flow rate is the target or actual flow rate of the reboiled steam at the bottom of the coarse separator, regulated by the steam control valve.

[0046] Specifically, based on the actual changes in the feed rate, the steam flow rate is proactively adjusted in advance without waiting for the temperature deviation to become apparent, thereby achieving proactive feedforward compensation of energy input and suppressing the impact of potential disturbances on the temperature of the upper part of the side mining area.

[0047] For example, feedforward control can detect changes in the disturbance (feed rate) before the disturbance affects the controlled variable (temperature) and adjust the manipulated variable (steam flow rate) in advance. Specific implementation methods can include simple proportional relationships, lookup tables, dynamic models, and others. For instance, the proportional relationship between "feed rate and steam flow rate" can be determined empirically; for example, if the feed rate increases by 10%, the steam flow rate increases by 8% accordingly.

[0048] In some embodiments, to avoid over-adjustment, the adjustment amount of feedforward control can be subject to amplitude limitation, rate of change limitation and necessary smoothing before being superimposed on the steam setpoint, while being compatible with existing safety interlocks and higher-level constraints, without replacing or bypassing safety protection.

[0049] S103. Based on the real-time temperature of the lower left temperature detection point and the corresponding first target control value, adjust the small return flow rate based on the cascade control of the lower left temperature-small return flow to reduce the temperature fluctuation of the lower left temperature detection point.

[0050] The small reflux is the liquid flow rate returning from the middle side sample of the coarse separator to the left side region. It is regulated by the small reflux control valve.

[0051] Cascade control of lower left-side temperature and small backflow: The lower left-side temperature is the controlled variable of the main loop, and the main loop outputs the setpoint of the target small backflow rate; the small backflow rate is the controlled variable of the secondary loop, and the secondary loop outputs the control signal for the small backflow valve. The main loop is slowed down, and the secondary loop is fastened, achieving separation of fast and slow flow and enhanced disturbance rejection.

[0052] Specifically, through a cascade structure combining fast and slow circuits, the secondary circuit prioritizes suppressing rapid disturbances from the actuator and flow channel, while the primary circuit focuses on the relatively slow process of temperature. The combination of the two can reduce temperature fluctuations and frequent valve operation.

[0053] S104. Based on the real-time temperature at the top temperature detection point, make compensatory adjustments to the large reflux flow rate to reduce temperature fluctuations at the top temperature detection point.

[0054] The large reflux is the liquid flow rate returning from the top condenser of the coarse fractionation column to the upper part of the right-side region, which is regulated by the large reflux control valve.

[0055] Compensatory adjustment (large reflux): Based on the real-time status of the column top temperature, an incremental or superimposed adjustment strategy is used to correct the set value or valve position of large reflux in order to suppress the fluctuation of the column top temperature.

[0056] Specifically, by monitoring the real-time changes in the temperature at the top of the tower, when the temperature shows an upward or downward trend and may cause fluctuations, the set value of the large reflux is adjusted appropriately to enhance the heat and material reflux in the top region of the tower, thereby suppressing the temperature deviation at the top of the tower.

[0057] Optionally, to ensure smooth operation and avoid undesirable coupling with other loops, the compensation amount of the large backflow setting can be applied to the original large backflow setting in a superimposed manner, and after amplitude limitation, rate of change limitation and small dead zone processing; when the condenser load, tower pressure or related equipment approaches the constraint, the compensation action is automatically weakened or suspended.

[0058] Large reflux adjustment affects the liquid flow rate in the upper right region, primarily impacting the tower top temperature; small reflux adjustment affects the liquid flow rate in the lower left region, mainly targeting temperature stability in the lower left region. Through feedforward and feedback coordinated control, the system achieves an organic combination of steam energy input adjustment and local reflux regulation under feed disturbances, effectively managing both dynamic and static disturbances, improving temperature stability, and enabling efficient and stable operation of the tower system.

[0059] In this embodiment, by acquiring the real-time feed rate and adjusting the steam flow rate accordingly, the heating supply is pre-matched to changes in the feed rate, reducing the deviation of the upper side temperature. By acquiring the lower left temperature and comparing it with the first target control value, the small reflux flow rate is adjusted based on the cascade control of the lower left temperature and the small reflux, reducing the fluctuation of the lower left temperature. By acquiring the top temperature and compensating for the large reflux flow rate, the fluctuation of the top temperature is suppressed. The above-mentioned coordinated regulation of steam, small reflux, and large reflux driven by multiple detection points keeps the temperature of each key area closer to the target state under disturbance and coupling conditions, reducing the overall temperature fluctuation in the tower and thus improving the control accuracy of the entire coarse separator.

[0060] Optionally, the above S102 may specifically include the following steps:

[0061] Obtain the real-time flow rate and steam flow rate setpoint at the bottom of the coarse separator;

[0062] The steam flow rate of the coarse feed tower is adjusted based on the real-time feed rate, the first gain coefficient and the first delay coefficient of the real-time feed rate, the steam flow rate setpoint, the second gain coefficient and the second delay coefficient of the steam flow rate setpoint, the real-time flow rate sampled from the bottom side, and the third gain coefficient and the third delay coefficient of the real-time flow rate sampled from the bottom side.

[0063] Wherein, the first gain coefficient is the proportionality coefficient of the intensity and direction of the steady-state influence of the real-time feed rate on the temperature of the upper part of the side-mining; the first delay coefficient is the time delay coefficient of the influence of the real-time feed rate change on the temperature of the upper part of the side-mining.

[0064] The second gain coefficient is the proportionality coefficient of the intensity and direction of the steady-state influence of the steam flow rate setpoint on the temperature of the upper part of the side-mining area; the second delay coefficient is the time delay coefficient of the effect of the change in the steam flow rate setpoint on the temperature of the upper part of the side-mining area.

[0065] The third gain coefficient is the proportionality coefficient of the intensity and direction of the steady-state influence of the real-time flow rate at the bottom side sampling point on the temperature at the top of the side sampling point; the third delay coefficient is the time delay coefficient of the influence of the real-time flow rate change at the bottom side sampling point on the temperature at the top of the side sampling point.

[0066] The first gain coefficient, the first delay coefficient, the second gain coefficient, the second delay coefficient, the third gain coefficient, and the third delay coefficient are identified through step response tests or historical data and obtained by fitting an ideal pure time delay model or a first-order inertial plus pure time delay model.

[0067] Step response test: A small, identifiable step change is applied to a single input variable, and the dynamic response curve of the upper temperature is recorded to extract the influence intensity and time lag.

[0068] Steam flow setpoint: refers to the target setpoint for the reboiling steam of the coarse separator, which is used by the control system to drive the steam regulating valve or steam circuit to achieve the corresponding heating level.

[0069] Specifically, the control system continuously collects real-time feed rate, steam flow setpoint, and bottom side sampling real-time flow rate; based on step response test or historical data identification results under different operating conditions, it extracts the intensity, direction, and time lag of the influence of real-time feed rate, steam flow setpoint, and bottom side sampling real-time flow rate on the upper temperature of the side sampling area; it uses an ideal pure time delay or a first-order inertia plus pure time delay model to fit the above influence relationship, obtaining the corresponding gain coefficient and delay coefficient parameter set, which is incorporated into the control system for online calculation; within each sampling period, the control system reads the real-time feed rate, steam flow setpoint, and bottom side sampling real-time flow rate, and combines the corresponding gain coefficient and delay coefficient to calculate the possible offset trend and arrival time of these factors on the upper temperature of the side sampling area; it converts the above trend into the advance adjustment amount of steam flow rate, and synthesizes it with the current steam flow setpoint to form the steam flow rate adjustment result for execution.

[0070] In this embodiment, by incorporating the real-time feed rate, steam flow rate setpoint, and bottom side sampling real-time flow rate into the same feedforward calculation framework, and combining their respective influence intensity, direction, and time lag on the upper side sampling temperature for parameterized characterization and online superposition adjustment, the steam flow rate can be targeted and corrected in advance before the disturbance reaches the upper side sampling area, thereby effectively reducing the temperature fluctuation at the detection point and improving control accuracy.

[0071] In one example, the above-mentioned feedforward control of the steam flow rate of the coarse separator based on the real-time feed rate can be performed by the following formula (1):

[0072] In the steam flow control scheme, the feed rate is increased to provide feedforward compensation for the temperature at the upper temperature detection point of the side sampling point in advance to respond to load fluctuations, as shown in formula (1):

[0073] (1)

[0074] Among them, TIC103.PV is the real-time temperature of the upper side sampling, FIC105.SV is the steam flow rate setpoint, FIC101.PV is the real-time feed rate, and the bottom side sampling flow rate is the actual flow rate of the bottom side sampling outlet.

[0075] Formula (1) above uses an ideal pure time delay model, and its transfer function is: ,in The time delay is the pure time delay. From the above formula (1), it can be seen that in this example, the first gain coefficient is -0.15, the first delay coefficient is 8s, the second gain coefficient is -1.5, the second delay coefficient is 6s, the third gain coefficient is -0.07, and the third delay coefficient is 2s.

[0076] FIC105.SV represents the influence channel of the steam flow setpoint (FIC105.SV) on the upper temperature of the side sampling (TIC103.PV). The steady-state gain is −1.5, indicating that when FIC105.SV increases, the direction of its effect on TIC103.PV decreases, with an amplitude ratio of 1.5. The pure hysteresis is 6 s, meaning that the effect begins to manifest after about 6 seconds.

[0077] The bottom-side sampling flow rate represents the influence channel of the actual flow rate from the bottom side sampling point on TIC103.PV; the steady-state gain is −0.07, indicating that when the bottom-side sampling flow rate increases, the direction of the effect on TIC103.PV decreases, and the magnitude ratio is 0.07; the pure hysteresis is 2 s, meaning that the effect begins to manifest after about 2 seconds.

[0078] FIC101.PV represents the influence channel of the real-time feed rate (FIC101.PV) on TIC103.PV; the steady-state gain is −0.15, indicating that when FIC101.PV increases, the direction of its effect on TIC103.PV decreases, with an amplitude ratio of 0.15; the pure hysteresis is 8 s, meaning that the effect begins to manifest after about 8 seconds.

[0079] Formula (1) can be used to adjust the steam flow rate in the feedforward control to offset the temperature disturbance in the upper part of the side-mining area, thus avoiding large fluctuations in the temperature of the upper part of the side-mining area.

[0080] Optionally, S103 may specifically include the following steps:

[0081] The main control loop performs PID calculations based on the deviation between the real-time temperature of the temperature detection point on the lower left and the first target control value, and generates the target flow setpoint for small backflow.

[0082] The secondary control loop performs PID calculations based on the deviation between the target flow setpoint and the real-time flow of the small return flow, and outputs a control signal to the small return flow control valve to adjust the small return flow.

[0083] The main control loop and the secondary control loop constitute a cascade control of temperature and small backflow on the lower left side. The output of the main control loop serves as the setpoint for the secondary control loop, and the output of the secondary control loop serves as the control signal for the actuator.

[0084] The temperature detection point on the lower left is located at a lower position on the left side of the coarse separator. The cascade control structure is a two-layer control structure consisting of a main control loop and a secondary control loop. The main loop uses temperature as the controlled variable and outputs the target small backflow rate setpoint; the secondary loop uses the small backflow rate as the controlled variable and outputs a control signal to the actuator (e.g., the small backflow rate control valve).

[0085] Specifically, the main control loop compares the real-time temperature of the lower left side with the first target control value, performs PID calculation on the deviation between the two, and outputs the calculation result as the target flow setpoint for the small reflux to the secondary control loop. The secondary control loop compares the target flow setpoint for the small reflux with the real-time flow of the small reflux, performs PID calculation on the deviation, and outputs a control signal from the actuator to the small reflux flow control valve, thereby changing the small reflux flow and making the actual flow follow the target flow setpoint as quickly as possible. With the rapid correction of the small reflux flow by the secondary control loop, the deviation of the temperature of the lower left side is reduced, and the output of the main control loop tends to stabilize. The two loops cooperate with each other in a continuous closed loop, making the temperature of the lower left side fluctuate stably around the first target control value.

[0086] In one example, when the temperature in the lower left area deviates from the first target control value, the main control loop generates a higher or lower target flow rate setpoint for the small return flow. After receiving the setpoint, the secondary control loop compares the real-time flow rate of the small return flow and outputs a control signal to the small return flow valve, so that the actual flow rate of the small return flow approaches the setpoint. As the effect of the small return flow change on the lower left area gradually becomes apparent, the temperature deviation is weakened, and the output of the main control loop gradually returns to a stable level, forming a stable cascade closed loop.

[0087] In this embodiment, by acquiring the real-time temperature and the real-time flow rate of the small reflux at the lower left side, and constructing a cascade control structure with temperature as the main loop and small reflux as the secondary loop, the main control loop generates a target flow rate setpoint for the small reflux based on the deviation between the temperature and the first target control value. The secondary control loop then drives the small reflux valve to achieve rapid tracking, thereby effectively reducing temperature fluctuations at the temperature detection point at the lower left side. The reduction in temperature fluctuations brings the temperature closer to the target value, further improving control accuracy.

[0088] Optionally, the top temperature detection point may include a second temperature detection point at the top of the column, which is located above the reflux inlet area at the top of the crude fractionation column. In this case, step S104 may specifically include the following steps:

[0089] Obtain the real-time flow rate and setpoint of the large backflow rate. The setpoint of the large backflow rate is the setpoint of the regulating valve used to drive the large backflow.

[0090] When a change in the large reflux setpoint or the large reflux real-time flow rate is detected, the predicted offset of the second temperature at the top of the tower is determined based on the real-time temperature at the second temperature detection point at the top of the tower and the change in the real-time flow rate of the large reflux.

[0091] Based on the predicted offset, determine the compensation amount for the large return flow rate;

[0092] The set value of the large reflux flow rate is adjusted according to the compensation amount to reduce the fluctuation of the second temperature at the top of the column through compensatory adjustment.

[0093] The second temperature detection point at the top of the column is located above the reflux entry area at the top of the coarse separator column, reflecting the temperature state formed in the upper region after the reflux enters. The real-time reflux flow rate is the online flow measurement value in the reflux pipeline, used as actual feedback on the reflux flow rate. The reflux flow rate setpoint is the target setpoint used to drive the reflux regulating valve. The predicted offset is used to characterize the expected impact of reflux changes on the temperature in the upper region at the top of the column.

[0094] The compensation amount refers to the adjustment made to the large return flow rate setpoint to offset the prediction offset and maintain the second temperature at the top of the column near the target control value. The magnitude and direction of the compensation amount are determined by the prediction offset: when the predicted temperature is going to rise, the compensation amount of the large return flow rate is increased (causing the temperature to decrease); when the predicted temperature is going to fall, the compensation amount of the large return flow rate is decreased (causing the temperature to rise).

[0095] Specifically, the system continuously reads the real-time large reflux flow rate and the large reflux flow rate setpoint, while simultaneously monitoring the real-time temperature of the second temperature at the top of the column. It monitors changes in either the "large reflux setpoint" or the "large reflux real-time flow rate," and when either changes, determines the predicted offset (direction and magnitude) of the "second temperature at the top of the column" based on this change and the real-time temperature of the second temperature. Then, the predicted offset is converted into a "compensation amount for the large reflux flow rate," ensuring that the compensation direction is opposite to the predicted offset direction, with the aim of offsetting any impending temperature shift. Finally, the "compensation amount" is superimposed on the "large reflux flow rate setpoint" to form a new, compensated setpoint. The control system transmits this new setpoint to the large reflux regulating valve, causing the reflux flow rate to adjust accordingly, thereby suppressing fluctuations in the second temperature at the top of the column.

[0096] In this embodiment, by setting a second temperature detection point at the top of the column in the upper part of the reflux inlet area, the impact of large reflux flow rate changes on the column top temperature can be detected in a timely and accurate manner. By acquiring the real-time large reflux flow rate and the flow rate setpoint, flow rate change signals can be captured promptly. When a flow rate change is detected, based on the real-time temperature of the second temperature detection point at the top of the column and the change in the real-time large reflux flow rate, and considering the expected impact of the current temperature state and flow rate change, the offset of the second temperature at the top of the column is predicted, realizing feedforward prediction of temperature fluctuations. The corresponding compensation amount is determined based on the predicted offset, and the large reflux flow rate setpoint is adjusted in a timely manner, allowing for preventative adjustments before significant temperature fluctuations occur, fundamentally reducing the disturbance impact of large reflux flow rate changes on the column top temperature. This overcomes the lag problem in temperature control, significantly reduces the fluctuation amplitude of the column top temperature, and improves the stability and speed of temperature control, thereby ensuring the stable operation of the coarse separation column and the stability of product quality.

[0097] Optionally, when a change in the large reflux setpoint or the large reflux real-time flow rate is detected, the predicted offset of the second temperature at the top of the column is determined based on the amount of change in the large reflux setpoint or the large reflux real-time flow rate. Specifically, this may include:

[0098] When a change in the large return flow setpoint or the large return flow real-time flow is detected, the amount of change in the large return flow real-time flow is determined.

[0099] When the change in real-time flow rate of the large reflux exceeds the preset threshold, the impact of the change in large reflux flow rate on the second temperature at the top of the tower is calculated based on the dynamic model of the large reflux to the second temperature at the top of the tower and the change in real-time flow rate of the large reflux.

[0100] Based on the influence amount and the real-time temperature of the second temperature detection point at the top of the tower, the predicted offset of the second temperature at the top of the tower is determined.

[0101] Among them, the dynamic model of the large return flow to the second temperature at the top of the tower is a first-order inertial plus pure time delay transfer function identified through step response test. The dynamic model of the large return flow to the second temperature at the top of the tower is used to describe the dynamic response relationship of the large return flow rate change to the second temperature at the top of the tower.

[0102] A preset threshold is a critical value used to determine whether changes in the real-time flow rate of a large return flow are significant. The compensatory adjustment mechanism is only triggered when the change in the real-time flow rate of the large return flow exceeds this threshold. The purpose of setting a preset threshold is to avoid frequent adjustments for minor flow fluctuations, preventing excessive actions and oscillations in the control system. In practical applications, the preset threshold can be set to 0.5%-2% of the normal operating flow rate. For example, for a system with a normal large return flow rate of 100 tons / hour, the preset threshold can be set to 0.5-2 tons / hour. This threshold can be adjusted and optimized based on actual operating results.

[0103] The dynamic model of the second temperature at the top of the column due to large reflux is a mathematical model describing the influence of large reflux flow rate changes on the second temperature at the top of the column. It characterizes the dynamic change of temperature response as the output signal when the flow rate change is taken as the input signal. This model not only reflects the steady-state relationship (i.e., gain) between flow rate and temperature, but also reflects the dynamic characteristics of the temperature response, including the response delay time and response speed. Optionally, this dynamic model can be a transfer function model in process control, expressing the input-output relationship in Laplace transform form, which can accurately describe the dynamic behavior of the system and provide a quantitative basis for predicting temperature changes.

[0104] The first-order inertial plus pure time delay transfer function is a commonly used dynamic model in the field of process control, and it is suitable for describing the dynamic characteristics of most chemical processes.

[0105] The impact of large reflux flow rate changes on the second temperature at the top of the column refers to the temperature change caused by the large reflux flow rate changes. It represents the temperature change caused solely by the flow rate change, without considering other factors. The impact is calculated using a dynamic model and reflects the causal effect of flow rate changes on temperature.

[0106] Specifically, the setpoint and real-time flow rate of the large return flow are monitored in real time. Within the sampling period, the real-time flow rate change is calculated for subsequent threshold determination and model prediction. This change is compared to a preset threshold; the dynamic model's prediction calculation is triggered only when the change exceeds the threshold, avoiding unnecessary compensation calculations for minor disturbances. If the threshold is exceeded, the change and the real-time temperature of the second temperature at the top of the tower are used as inputs to the dynamic model from the large return flow to the second temperature at the top of the tower, obtaining the predicted offset of the second temperature at the top of the tower. This predicted offset is used to determine the compensation amount and the setpoint correction process, thereby completing targeted compensation before the actual offset of the second temperature at the top of the tower is reached.

[0107] In this embodiment, by setting a preset threshold to filter the changes in real-time flow rate of the large return flow, the compensation mechanism is activated only for significant flow rate changes exceeding the threshold. This effectively avoids frequent responses to small flow rate fluctuations, prevents excessive action and oscillation of the control system, and improves the stability of the control system. By using the first-order inertial plus pure time delay transfer function identified based on step response testing as the dynamic model of the large return flow to the second temperature at the top of the tower, the dynamic response relationship of the large return flow rate change to the second temperature at the top of the tower is accurately described. This model not only reflects the steady-state gain relationship between flow rate and temperature, but also accurately characterizes dynamic characteristic parameters such as pure time delay and inertial time constant, providing a scientific and reliable mathematical basis for the quantitative calculation of temperature influence. The influence calculated based on the dynamic model and the flow rate change accurately quantifies the expected impact of flow rate change on temperature. Combined with the real-time temperature of the second temperature detection point at the top of the tower, the prediction offset is determined. This considers both the expected impact of flow rate change and the actual state of the current temperature, enabling the prediction offset to comprehensively reflect the future deviation trend of temperature, and significantly improving the prediction accuracy.

[0108] The compensation adjustment based on accurate predicted offset is more precise and reasonable, which can effectively offset the disturbance of temperature caused by flow rate changes, control the temperature fluctuation range within a smaller range, significantly improve the accuracy and stability of the tower top temperature control, and ensure the stable and efficient operation of the coarse separator.

[0109] Optionally, the above-mentioned control method for the diaphragm-type side-extraction coarse separator may further include the following steps:

[0110] For the temperature detection point at the upper part of the side sampling, the second target control value corresponding to the temperature at the upper part of the side sampling is determined based on the real-time feed rate, the first temperature response coefficient, and the first basic temperature constant.

[0111] The setpoint of the temperature control valve at the upper part of the side sampling area is adjusted based on the second target control value.

[0112] The first temperature response coefficient is the sensitivity coefficient of the side sampling upper temperature to changes in feed rate, and the first basic temperature constant is the reference temperature value of the side sampling upper temperature under the theoretical zero feed rate condition. The setpoint of the control valve is the given value of the execution channel controlling the side sampling upper temperature (e.g., the setpoint of the corresponding manipulator loop), used to actually adjust the process variable to track the target.

[0113] Specifically, when the real-time feed rate increases, a new second target control value is calculated based on the first temperature response coefficient and the first basic temperature constant; the control system adjusts the control valve setpoint accordingly to make the temperature at the upper part of the side sampling track the second target control value; when the feed rate decreases, the above process is reversed.

[0114] In this embodiment, by designing the target value of the upper side sampling temperature as a second target control value that linearly follows the real-time feed rate, and directly driving the set value of the temperature control valve to adjust accordingly, the temperature control target is kept consistent with the load change, reducing the systematic deviation caused by the fixed target value, thereby better constraining the deviation of the upper side sampling temperature under the condition of feed fluctuation, and thus weakening the temperature fluctuation.

[0115] In one example, the second target control value corresponding to the above-mentioned side sampling upper temperature can be determined by the following formula (2):

[0116] TIC103.PV=a×FIC101.PV+b (2)

[0117] Wherein, TIC103.PV is the real-time temperature value of the upper temperature detection point (9) of the side sampling, FIC101.PV is the real-time feed amount of the feed inlet (1), a is the coefficient of the feed amount FIC101.PV, which reflects the sensitivity of the feed amount to the temperature; b is the constant term coefficient, which represents the reference temperature offset.

[0118] According to the above formula (2), the second target control value can be calculated as follows: a⋅FIC101.PV+b. As FIC101.PV changes, the second target control value is updated in real time according to formula (2).

[0119] In a specific embodiment, such as Figure 2 The control of the baffle-type side-collection coarse separator shown includes: feed inlet (1), steam heating inlet (2), small reflux branch (3), lower left detection point (4), pressure detection point at the top of the tower (5), first temperature detection point at the top of the tower (6), large reflux (7), second temperature detection point at the top of the tower (8), upper side-collection temperature detection point (9), and liquid level detection point at the side-collection port (10).

[0120] The feed inlet (1) is equipped with a flow indicator controller for feed flow control. FIC101.PV is the real-time feed flow rate, and FIC101.SV is the target feed amount.

[0121] The steam heating inlet (2) is equipped with a flow indicator controller for controlling the steam flow of the reboiler. FIC105.PV is the real-time steam flow rate, and FIC105.SV is the steam setpoint.

[0122] The small return flow (3) is equipped with a flow indicator controller to control the flow rate of the small return flow (side line return flow). FIC103.PV is the real-time small return flow rate, and FIC103.SV is the target value of the small return flow rate.

[0123] A temperature indicator is provided at the lower left detection point (4) to detect the bottom / bottom temperature of the column. TI104.PV is the bottom temperature of the crude fractionation column, i.e., the temperature at the lower left.

[0124] The pressure detection point (5) at the top of the tower is equipped with a pressure indicator for detecting the pressure at the top of the tower. PI101.PV is the pressure at the top of the tower.

[0125] The first temperature detection point (6) at the top of the tower is equipped with a temperature indicator for detecting the temperature in the top area of ​​the tower. TI101.PV is the first temperature at the top of the tower, which is also the main control temperature at the top of the tower.

[0126] The large return flow (7) is equipped with a flow indicator controller to control the top return flow (large return flow) flow. FIC102.PV is the real-time top mining flow (real-time flow of large return flow), and FIC102.SV is the top mining set value (set flow of large return flow).

[0127] The second temperature detection point (8) at the top of the tower is equipped with a temperature indicator for detecting the temperature of the upper tray / reflux line. TI102.PV is the temperature of the upper tray / reflux line.

[0128] The upper temperature detection point (9) of the side sampling is equipped with a temperature controller to control the temperature of the upper detection point of the side sampling. TIC103.PV is the real-time upper temperature of the side sampling, and TIC103.SV is the set value of the upper temperature of the side sampling.

[0129] The side sampling port liquid level detection point (10) is equipped with a liquid level indicator to detect the liquid level in the bottom / recirculation loop of the tower. LI103.PV is the liquid level in the bottom / recirculation loop of the tower.

[0130] exist Figure 2 Based on the control architecture shown, the specific implementation process of the above-mentioned diaphragm-type side-source coarse-digestion tower control method in practical applications is as follows:

[0131] I. Digital Twin Modeling and Simulation Analysis.

[0132] Step 1: Based on the actual structure of the diaphragm tower, build a coarse-grained tower model in simulation software and accurately set the number of packing layers, interlayer height / width, and temperature point distribution.

[0133] The simulation model was built and simulated using Aspen Plus, such as... Figure 5 The simulation model is based on the actual structure of the baffle-type side-drawing coarse separator. The number of trays is converted into the number of packing layers according to the packing height in the drawing and input into the model. The interlayer height / width and temperature point distribution are set. This coarse separator is set to have three extraction points: top extraction S2, side extraction S3, and bottom extraction S4. The specific extraction locations are set according to the actual PID drawing. The simulation model of the baffle-type side-drawing coarse separator is obtained.

[0134] Step 2: Input the actual operating parameters into the simulation model.

[0135] Actual operating parameters include: setting feed S1 component, mass flow rate, feed temperature, feed pressure, tower top pressure, reflux flow rate, etc., based on actual production and testing data. The actual operating conditions are mapped to the simulation model, and operating condition reproduction experiments are conducted.

[0136] Step 3: Through simulation calculations, output the theoretical values ​​of the temperature points of each tray, and compare them with the actual operating data to identify the differences.

[0137] The simulation calculation is run to output the theoretical values ​​of the temperature of each tray. The theoretical values ​​are found according to the installation position of the temperature sensor in the PID drawing. The theoretical values ​​are then compared with the actual operating temperature sensor data to identify key points with significant deviations (such as the temperature at the top of the tray, the temperature at the lower left side, and the temperature at the upper side sampling point).

[0138] II. Optimization of control parameters and experimental verification.

[0139] For temperature points where simulation and actual measurements show significant deviations, adjustment test plans and emergency measures were developed. Under fixed feed conditions, the steam flow rate was gradually adjusted, and the changes in three key temperature points (top temperature, lower left side temperature, and upper side sampling temperature) were monitored. The small reflux flow rate and feed load were adjusted sequentially, and the responses at key temperature points and changes in test results were observed. A comprehensive analysis of the correlation between temperature points and steam, reflux, and feed was conducted to establish a dynamic control relationship. The specific process is as follows:

[0140] 1): Data analysis and diagnosis. Based on the comparison and analysis of simulation results and actual data, it was found that the temperature of the second temperature detection point (8) at the top of the tower was frequently at the upper or lower control limit, and the actual temperature of the upper temperature detection point (9) on the side exceeded the theoretical temperature by about 7°C.

[0141] 2): On-site cause analysis. Based on the actual production site, analyze the causes of the problem, which mainly include: fluctuations in the feed to the coarse separator, lag in steam control temperature, and ineffective utilization of large and small reflux, etc.

[0142] 3): Develop a testing, verification, and optimization plan. Based on the above analysis results, conduct targeted testing, verification, and optimization work, including temperature control optimization, APC (Advanced Process Control) model optimization, and prediction of feed fluctuations in the coarse separator.

[0143] 4): Steady-state control of the temperature at the first temperature detection point (6) at the top of the tower and the large reflux (7) using APC. The control range of the first temperature at the top of the tower and the advanced control (APC) model are optimized. In the advanced control (APC) system, the temperature at the top of the tower is controlled by the top reflux (large reflux). The top temperature control range is set to the set value ±0.3℃. Steady-state control is achieved through automatic adjustment of the top reflux.

[0144] 5): The dynamic range of large return flow (7) is expanded, and the upper and lower limits of large return flow regulation are expanded from the original 15 T / H to 25 T / H, enhancing load adaptability.

[0145] 6): The temperature of the side sampling temperature, i.e. the temperature detection point (9) at the upper part of the side sampling, is optimized in a stepwise manner. The relationship between the actual temperature change of the side sampling and the content of the side sampling is analyzed. The temperature set value is reduced in stages (1℃ on the first day, 2℃ on the second day, and 3℃ on the third day). The changes in the TCS content of the side sampling and the temperature (4) at the lower left side are monitored daily to verify the separation effect.

[0146] 7): Increase the coordinated control of the temperature of the small reflux (3) and the lower left detection point (4), manually adjust the small reflux flow rate, and stabilize the temperature (4) of the lower left side near the simulation theoretical value.

[0147] 8): Dynamic test of feed rate at feed inlet (1). By adjusting the feed load, repeat steps 5) to 7), record the temperature of the second temperature detection point (8) at the top of the tower, the temperature of the upper side temperature detection point (9), and the component data, and analyze the change pattern.

[0148] III. Control Scheme Upgrade and System Solidification

[0149] Based on the field experimental data and optimization process, an optimization strategy was formulated and implemented according to the test results: the control logic was optimized based on the experimental data to achieve dynamic adjustment of key temperature points according to the feed load; the temperature control range of the sensitive plate was dynamically set for different production loads; a temperature-small reflux control loop was added to the lower left side to improve the stability of side sampling; a feed-sensitive plate temperature feedforward control model was established to respond to load changes in advance; and the second temperature point-reflux control model at the top of the tower was integrated into the advanced control system to suppress temperature fluctuations.

[0150] The specific optimization strategies are as follows:

[0151] Strategy A: Feedforward control.

[0152] like Figure 3 The control architecture shown adds feedforward compensation to the temperature (TIC103.PV) at the upper temperature detection point (9) of the side sampling system to respond to load fluctuations in advance, based on the control scheme of the steam flow (FIC105.PV) at the steam heating inlet (2). Specifically, it is shown in formula (1).

[0153] TIC103.PV= FIC105.SV Bottom side flow rate FIC101.PV (1)

[0154] Where TIC103.PV is the real-time temperature at the top of the side sampling, FIC105.SV is the steam flow rate setpoint, FIC101.PV is the real-time feed rate, and the bottom side sampling flow rate is the actual flow rate at the bottom side sampling outlet. An ideal pure time-delay system is used, and its transfer function is: ,in This is the pure time delay.

[0155] Strategy A allows for the adjustment of steam flow rate within the feedforward control to counteract temperature disturbances at the upper part of the side-mining area, thus preventing large fluctuations in the upper temperature of the side-mining area.

[0156] Strategy B: Establish cascade control of the temperature (TI104.PV) of the lower left detection point (4) and the small reflux (3) to improve local temperature stability.

[0157] like Figure 4 The cascade control shown has a main loop for temperature control and an inner loop for side-source flow control.

[0158] (1) Main control circuit (temperature control circuit).

[0159] Controlled variable: Lower left temperature (TI104.PV);

[0160] Controller: Main PID controller module;

[0161] Control objective: Maintain the temperature on the lower left side near the process setpoint.

[0162] (2) Secondary control loop (flow control loop).

[0163] Controlled variable: Small return flow rate (FIC103.PV);

[0164] Controller: Sub-PID controller module;

[0165] Actuator: Flow control valve (FV103);

[0166] Control objective: To respond quickly to the output commands of the main controller and precisely adjust the small return flow rate.

[0167] The temperature signal (TI104.PV) and the small reflux flow rate signal (FIC103.PV) of the lower left side are collected in real time. The secondary PID controller receives the output of the main controller as its setpoint and performs PID calculation based on the actual value of the small reflux flow rate (FIC103.PV). It outputs a control signal to the flow control valve (FV103) to adjust the small reflux flow rate. The change in the small reflux flow rate affects the gas-liquid distribution in the column, thereby stabilizing the temperature of the lower left side.

[0168] Strategy C: Develop a dynamic calculation formula (2) for the temperature (TIC103.PV) of the upper temperature detection point (9) at the side sampling point and the feed rate (FIC101.PV) at the feed inlet (1), and achieve parameter linkage optimization:

[0169] TIC103.PV=a×FIC101.PV+b (2)

[0170] Wherein, TIC103.PV is the real-time temperature value of the upper temperature detection point (9) of the side sampling, FIC101.PV is the real-time feed amount of the feed inlet (1), a is the coefficient of the feed amount FIC101.PV, which reflects the sensitivity of the feed amount to the temperature; b is the constant term coefficient, which represents the reference temperature offset.

[0171] The coefficients a and b can be determined in the following ways: (1) Historical data regression analysis: collect stable operating data under different feed loads and perform linear regression using the least squares method. (2) On-site test verification: conduct step tests within a safe range to verify the accuracy and applicability of the model. (3) Online self-tuning: set an adaptive mechanism to automatically update the coefficient values ​​based on the operating data.

[0172] Specifically, FIC101.PV data can be collected online in real time, and the optimal temperature setpoint can be calculated according to formula (2); the calculated TIC103.SV is used as the setpoint of the temperature controller; upper and lower limits of the temperature setpoint are set to ensure operational safety; a rate limiting algorithm is adopted to avoid system disturbance caused by sudden changes in the setpoint. The temperature setpoint is dynamically optimized with the feed rate, and product quality fluctuations are reduced.

[0173] Strategy D: Integrate the prediction model of the temperature (TI102.PV) of the second temperature detection point (8) at the top of the tower and the flow rate (FIC102.SV) of the large reflux (7) in the advanced control (APC), i.e., formula (3), to suppress the fluctuation of the second temperature point at the top of the tower.

[0174] TI102.PV= FIC102.SV (3)

[0175] Among them, FI102.PV is the real-time temperature of the second temperature detection point, and FIC102.SV is the top extraction set value (large reflux set flow rate).

[0176] Formula (3) is essentially a prediction model of large reflux flow rate → second temperature at the top of the tower (i.e., dynamic model of large reflux to second temperature at the top of the tower). Based on formula (3), the disturbance can be offset in advance by controlling the large reflux flow rate in APC / feedforward, which can effectively suppress the temperature fluctuation of the second temperature detection point (8).

[0177] Final implementation: The above control scheme is configured and downloaded through the DCS / PLC system, the algorithm is solidified, and fully automatic operation is achieved.

[0178] In this embodiment, the key control points and regulation strategies of the coarse separator were identified through a combination of simulation guidance and experimental verification. This solved the problems of frequent manual intervention and poor stability, and achieved: fully automatic steady-state control, reducing reliance on manual adjustment; dynamic optimization of key parameters to adapt to different production loads; improved temperature stability and product quality; reduced energy consumption through precise control of reflux ratio and steam consumption; and improved product quality stability, avoiding risks of gas entrainment and temperature exceeding limits.

[0179] Example 2:

[0180] like Figure 6 As shown, this embodiment provides a diaphragm-type side-extraction coarse separator control device for executing the above-described coarse separator control method, including:

[0181] The acquisition module 601 is used to acquire the real-time feed rate of the coarse separation tower and the real-time temperature of the target detection point. The target detection point includes at least the top detection point and the lower left detection point.

[0182] The first control module 602 is connected to the acquisition module 601 and is used to perform feedforward control on the steam flow of the coarse separator based on the real-time feed rate, so as to reduce the temperature fluctuation of the upper part of the side sampling. The feedforward control is a control method that adjusts the steam flow in advance according to the change of the feed rate.

[0183] The second control module 603, connected to the first control module 602, is used to adjust the small reflux flow rate based on the real-time temperature of the temperature detection point at the lower left side and the corresponding first target control value, in order to reduce the temperature fluctuation at the temperature detection point at the lower left side. The small reflux is the liquid flow rate returning from the middle side sampling section of the coarse separator to the left area, and the cascade control is a dual-loop control structure that controls the small reflux flow rate based on the temperature at the lower left side.

[0184] The third control module 604, connected to the second control module 603, is used to compensate for the large reflux flow rate based on the real-time temperature of the top temperature detection point, so as to reduce the temperature fluctuation at the top temperature detection point; the large reflux is the liquid flow rate returning from the top condenser of the coarse fractionation column to the upper part of the right side region.

[0185] Optionally, the first control module 602 includes:

[0186] The first acquisition unit is used to acquire the real-time flow rate and steam flow rate setpoint at the bottom side of the coarse separator.

[0187] The first adjustment unit is used to adjust the steam flow rate of the coarse feed tower based on the real-time feed rate, the first gain coefficient and the first delay coefficient of the real-time feed rate, the steam flow rate setpoint, the second gain coefficient and the second delay coefficient of the steam flow rate setpoint, the real-time flow rate sampled from the bottom side, and the third gain coefficient and the third delay coefficient of the real-time flow rate sampled from the bottom side.

[0188] Wherein, the first gain coefficient is the proportionality coefficient of the intensity and direction of the steady-state influence of the real-time feed rate on the temperature of the upper part of the side-mining; the first delay coefficient is the time delay coefficient of the influence of the real-time feed rate change on the temperature of the upper part of the side-mining.

[0189] The second gain coefficient is the proportionality coefficient of the intensity and direction of the steady-state influence of the steam flow rate setpoint on the temperature of the upper part of the side mining area; the second delay coefficient is the time delay coefficient of the effect of the change in the steam flow rate setpoint on the temperature of the upper part of the side mining area.

[0190] The third gain coefficient is the proportionality coefficient of the intensity and direction of the steady-state influence of the real-time flow rate at the bottom side sampling point on the temperature at the top of the side sampling point; the third delay coefficient is the time delay coefficient of the influence of the real-time flow rate change at the bottom side sampling point on the temperature at the top of the side sampling point.

[0191] The first gain coefficient, the first delay coefficient, the second gain coefficient, the second delay coefficient, the third gain coefficient, and the third delay coefficient are identified through step response tests or historical data and obtained by fitting an ideal pure time delay model or a first-order inertial plus pure time delay model.

[0192] Optionally, the second control module 603 mentioned above includes:

[0193] The first control unit is used to perform PID calculations based on the deviation between the real-time temperature of the temperature detection point on the lower left side and the first target control value through the main control loop, and generate the target flow setpoint for small backflow.

[0194] The second control unit is used to perform PID calculations based on the deviation between the target flow setpoint and the real-time flow of the small return flow through the sub-control loop, and output a control signal to the small return flow control valve to adjust the small return flow.

[0195] The main control loop and the secondary control loop constitute a cascade control of temperature and small backflow on the lower left side. The output of the main control loop serves as the setpoint for the secondary control loop, and the output of the secondary control loop serves as the control signal for the actuator.

[0196] Optionally, the top detection point includes a second temperature detection point at the top of the column, which is located above the reflux inlet area at the top of the crude fractionation column. The aforementioned third control module 604 includes:

[0197] The first acquisition unit is used to acquire the real-time flow rate of the large backflow and the set value of the large backflow, wherein the set value of the large backflow is the set value used to drive the regulating valve of the large backflow.

[0198] The first determining unit is used to determine the predicted offset of the second temperature at the top of the tower based on the real-time temperature of the second temperature detection point at the top of the tower and the change in the real-time flow rate of the large reflux when the large reflux setting value or the large reflux real-time flow rate is detected to change.

[0199] The second determining unit is used to determine the compensation amount for the large return flow based on the predicted offset.

[0200] The first adjustment unit is used to adjust the set value of the large reflux flow rate according to the compensation amount, so as to reduce the fluctuation of the second temperature at the top of the tower through compensatory adjustment.

[0201] Optionally, the first determining unit mentioned above includes:

[0202] The first determining subunit is used to determine the amount of change in the large return flow rate when the large return flow setting value or the large return flow rate changes.

[0203] The first prediction subunit is used to calculate the impact of the change in the large return flow rate on the second temperature at the top of the tower based on the dynamic model of the large return flow to the second temperature at the top of the tower and the change in the large return flow rate when the change in the real-time flow rate of the large return exceeds a preset threshold.

[0204] The second prediction subunit is used to determine the prediction offset of the second temperature at the top of the tower based on the influence amount and the real-time temperature of the second temperature detection point at the top of the tower.

[0205] Among them, the dynamic model of the large return flow to the second temperature at the top of the tower is a first-order inertial plus pure time delay transfer function identified by step response test. The dynamic model of the large return flow to the second temperature at the top of the tower is used to describe the dynamic response relationship of the large return flow rate change to the second temperature at the top of the tower.

[0206] Optionally, the third control module 604 mentioned above includes:

[0207] The third determining unit determines the second target control value corresponding to the temperature of the upper side sampling point based on the real-time feed rate, the first temperature response coefficient, and the first basic temperature constant. The first temperature response coefficient is the sensitivity coefficient of the upper side sampling temperature to the change in feed rate, and the first basic temperature constant is the reference temperature value of the upper side sampling temperature under the theoretical zero feed rate condition.

[0208] The second adjustment unit is used to adjust the set value of the temperature control valve on the upper part of the side sampling based on the second target control value.

[0209] In this embodiment, by acquiring the real-time feed rate and adjusting the steam flow rate accordingly, the heating supply is pre-matched to changes in the feed rate, reducing the deviation of the upper side temperature. By acquiring the lower left temperature and comparing it with the first target control value, the small reflux flow rate is adjusted based on the cascade control of the lower left temperature and the small reflux, reducing the fluctuation of the lower left temperature. By acquiring the top temperature and compensating for the large reflux flow rate, the fluctuation of the top temperature is suppressed. The above-mentioned coordinated regulation of steam, small reflux, and large reflux driven by multiple detection points keeps the temperature of each key area closer to the target state under disturbance and coupling conditions, reducing the overall temperature fluctuation in the tower and thus improving the control accuracy of the entire coarse separator.

[0210] Example 3:

[0211] Figure 7 A schematic diagram of the hardware structure of the electronic device provided in an embodiment of this application is shown.

[0212] An electronic device may include a processor 701 and a memory 702 storing computer program instructions.

[0213] Specifically, the processor 701 may include a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits that can be configured to implement the embodiments of this application.

[0214] Memory 702 may include mass storage for data or instructions. For example, and not limitingly, memory 702 may include a hard disk drive (HDD), floppy disk drive, flash memory, optical disk, magneto-optical disk, magnetic tape, or Universal Serial Bus (USB) drive, or a combination of two or more of these. Where appropriate, memory 702 may include removable or non-removable (or fixed) media. Where appropriate, memory 702 may be internal or external to the integrated gateway disaster recovery device. In a particular embodiment, memory 702 is non-volatile solid-state memory.

[0215] Memory may include read-only memory (ROM), random access memory (RAM), disk storage media devices, optical storage media devices, flash memory devices, and electrical, optical, or other physical / tangible memory storage devices. Therefore, typically, memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., memory devices) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the methods according to one aspect of this disclosure.

[0216] The processor 701 reads and executes computer program instructions stored in the memory 702 to implement any of the coarse-digestion tower control methods in the above embodiments.

[0217] In one example, the electronic device may also include a communication interface 703 and a bus 704. For example, Figure 7 As shown, the processor 701, memory 702, and communication interface 703 are connected through bus 704 and complete communication with each other.

[0218] The communication interface 703 is mainly used to realize communication between various modules, devices, units and / or equipment in the embodiments of this application.

[0219] Bus 704 includes hardware, software, or both, that couples components of an online data traffic metering device together. For example, and not limitingly, the bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), HyperTransport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an Infinite Bandwidth Interconnect, a Low Pin Count (LPC) bus, a memory bus, a Microchannel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local (VLB) bus, or other suitable buses, or combinations of two or more of these. Where appropriate, bus 704 may include one or more buses. Although specific buses are described and illustrated in embodiments of this application, any suitable bus or interconnect is contemplated herein.

[0220] Furthermore, in conjunction with the coarse-digesting tower control method in the above embodiments, this application embodiment can provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when these computer program instructions are executed by a processor, they implement any of the coarse-digesting tower control methods in the above embodiments.

[0221] It should be clarified that this application is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of this application is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of this application.

[0222] The functional blocks shown in the above block diagram can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this application are programs or code segments used to perform the required tasks. The programs or code segments can be stored on a machine-readable medium or transmitted over a transmission medium or coarse-pole control link via data signals carried on a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, fiber optic media, radio frequency (RF) links, etc. Code segments can be downloaded via computer networks such as the Internet, intranets, etc.

[0223] It should also be noted that the exemplary embodiments mentioned in this application describe methods or systems based on a series of steps or apparatus. However, this application is not limited to the order of the above steps; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0224] The aspects of this disclosure have been described above with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It should be understood that each block in the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that these instructions, executable via the processor of the computer or other programmable data processing apparatus, enable the implementation of the functions / actions specified in one or more blocks of the flowchart illustrations and / or block diagrams. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field-programmable logic circuit. It is also understood that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can also be implemented by special-purpose hardware performing the specified functions or actions, or can be implemented by a combination of special-purpose hardware and computer instructions.

[0225] The above are merely specific embodiments of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the protection scope of this application.

Claims

1. A control method for a diaphragm-type side-extraction coarse feed tower, characterized in that, include: The real-time feed rate of the coarse separation tower and the real-time temperature of the target detection points are obtained. The target detection points include at least: the temperature detection point at the top of the tower, the temperature detection point at the lower left side, and the temperature detection point at the upper side sampling point. Feedforward control is performed on the steam flow rate of the coarse separator based on the real-time feed rate to reduce the temperature fluctuation of the upper part of the side sampling. The feedforward control is a control method that adjusts the steam flow rate in advance according to the change of the feed rate. Based on the real-time temperature of the lower left temperature detection point and the corresponding first target control value, the small reflux flow rate is adjusted according to the cascade control of the lower left temperature and the small reflux to reduce the temperature fluctuation of the lower left temperature detection point; the small reflux is the liquid flow rate returning from the middle side sampling part of the coarse separator to the left area; the cascade control is a dual-loop control structure that controls the small reflux flow rate with the lower left temperature. Based on the real-time temperature at the top temperature detection point, the large reflux flow rate is adjusted compensatorily to reduce temperature fluctuations at the top temperature detection point; the large reflux is the liquid flow rate returning from the top condenser of the coarse fractionation column to the upper part of the right-side region.

2. The method according to claim 1, characterized in that, The step of feeding forward control of the steam flow rate of the coarse separator based on the real-time feed rate to reduce temperature fluctuations at the upper detection point of the side sampling section specifically includes: Obtain the real-time flow rate and steam flow rate setpoint at the bottom side of the coarse separator; The steam flow rate of the coarse feed tower is adjusted based on the real-time feed rate, the first gain coefficient and the first delay coefficient of the real-time feed rate, the steam flow rate setpoint, the second gain coefficient and the second delay coefficient of the steam flow rate setpoint, the real-time flow rate sampled from the bottom side, and the third gain coefficient and the third delay coefficient of the real-time flow rate sampled from the bottom side. Wherein, the first gain coefficient is the proportionality coefficient of the intensity and direction of the steady-state influence of the real-time feed rate on the temperature of the upper part of the side sampler; the first delay coefficient is the time delay coefficient of the influence of the real-time feed rate change on the temperature of the upper part of the side sampler. The second gain coefficient is a proportionality coefficient of the intensity and direction of the steady-state influence of the steam flow rate setpoint on the temperature of the upper part of the side-mining area; the second delay coefficient is a time delay coefficient of the effect of the change in the steam flow rate setpoint on the temperature of the upper part of the side-mining area. The third gain coefficient is the proportionality coefficient of the intensity and direction of the steady-state influence of the real-time flow rate at the bottom side sampling point on the temperature at the top of the side sampling point; the third delay coefficient is the time delay coefficient of the influence of the real-time flow rate change at the bottom side sampling point on the temperature at the top of the side sampling point. The first gain coefficient, the first delay coefficient, the second gain coefficient, the second delay coefficient, the third gain coefficient, and the third delay coefficient are identified through step response tests or historical data and fitted with an ideal pure time delay model or a first-order inertial plus pure time delay model.

3. The method according to claim 1, characterized in that, The adjustment of the small return flow rate based on the real-time temperature of the lower left temperature detection point and the corresponding first target control value, according to the cascade control of the lower left temperature and small return flow, specifically includes: The main control loop performs PID calculations based on the deviation between the real-time temperature of the temperature detection point on the lower left side and the first target control value to generate the target flow rate setpoint for small backflow. The secondary control loop performs PID calculations based on the deviation between the target flow setpoint and the real-time flow of the small return flow, and outputs a control signal to the small return flow control valve to adjust the small return flow. The main control loop and the secondary control loop constitute a cascade control of temperature-small backflow on the lower left side. The output of the main control loop serves as the setpoint for the secondary control loop, and the output of the secondary control loop serves as the control signal for the actuator.

4. The method according to claim 1, characterized in that, The tower top temperature detection point includes a second tower top temperature detection point, which is located above the reflux inlet area at the top of the coarse separator tower. The step of adjusting the large reflux flow rate in accordance with the real-time temperature at the top of the tower to reduce temperature fluctuations at the top of the tower includes: Obtain the real-time flow rate of the large backflow and the set value of the large backflow, wherein the set value of the large backflow is the set value used to drive the regulating valve of the large backflow. When a change in the large reflux setpoint or the large reflux real-time flow rate is detected, the predicted offset of the second temperature at the top of the tower is determined based on the real-time temperature at the second temperature detection point at the top of the tower and the change in the real-time flow rate of the large reflux. Based on the predicted offset, determine the compensation amount for the large return flow rate; The set value of the large reflux flow rate is adjusted according to the compensation amount to reduce the fluctuation of the second temperature at the top of the tower through compensatory adjustment.

5. The method according to claim 4, characterized in that, When a change in the large reflux setpoint or the large reflux real-time flow rate is detected, the predicted offset of the second temperature at the top of the tower is determined based on the real-time temperature at the second temperature detection point at the top of the tower and the change in the real-time flow rate of the large reflux. Specifically, this includes: When a change in the large return flow setting value or the large return flow real-time flow is detected, the amount of change in the large return flow real-time flow is determined. When the change in the real-time flow rate of the large reflux exceeds a preset threshold, the impact of the change in the large reflux flow rate on the second temperature at the top of the tower is calculated based on the dynamic model of the large reflux to the second temperature at the top of the tower and the change in the real-time flow rate of the large reflux. Based on the influence amount and the real-time temperature of the second temperature detection point at the top of the tower, the predicted offset of the second temperature at the top of the tower is determined; The dynamic model of the large reflux to the second temperature at the top of the tower is a first-order inertial plus pure time delay transfer function identified through step response testing. The dynamic model of the large reflux to the second temperature at the top of the tower is used to describe the dynamic response relationship of the large reflux flow rate change to the second temperature at the top of the tower.

6. The method according to claim 1, characterized in that, The method further includes: For the temperature detection point at the top of the side sampling, a second target control value corresponding to the temperature at the top of the side sampling is determined based on the real-time feed rate, the first temperature response coefficient, and the first basic temperature constant. The first temperature response coefficient is the sensitivity coefficient of the temperature at the top of the side sampling to changes in the feed rate, and the first basic temperature constant is the reference temperature value of the temperature at the top of the side sampling under the theoretical zero feed rate condition. The setpoint of the temperature control valve at the upper part of the side sampling is adjusted based on the second target control value.

7. A control device for a diaphragm-type side-harvesting coarse feed tower, characterized in that, The device includes: The acquisition module is used to acquire the real-time feed rate of the coarse separation tower and the real-time temperature of the target detection point. The target detection point includes at least: the tower top temperature detection point, the lower left temperature detection point, and the upper side sampling temperature detection point. The first control module, connected to the acquisition module, is used to perform feedforward control on the steam flow of the coarse separator based on the real-time feed rate, so as to reduce the temperature fluctuation of the upper part of the side sampling. The feedforward control is a control method that adjusts the steam flow in advance according to the change of the feed rate. The second control module, connected to the first control module, is used to adjust the small reflux flow rate based on the real-time temperature of the lower left temperature detection point and the corresponding first target control value, according to the cascade control of the lower left temperature and small reflux, so as to reduce the temperature fluctuation of the lower left temperature detection point; the small reflux is the liquid flow rate returning from the middle side sampling part of the coarse separator to the left region; the cascade control is a dual-loop control structure that controls the small reflux flow rate with the lower left temperature. The third control module, connected to the second control module, is used to compensate for the large reflux flow rate based on the real-time temperature of the tower top temperature detection point, so as to reduce the temperature fluctuation of the tower top temperature detection point; the large reflux is the liquid flow rate returning from the top condenser of the coarse fractionation tower to the upper part of the right side region.

8. The apparatus according to claim 7, characterized in that, The first control module includes: The first acquisition unit is used to acquire the real-time flow rate and steam flow rate set value at the bottom side of the coarse separator. The first adjustment unit is used to adjust the steam flow rate of the coarse separator based on the real-time feed rate, the first gain coefficient and the first delay coefficient of the real-time feed rate, the steam flow rate setpoint, the second gain coefficient and the second delay coefficient of the steam flow rate setpoint, the bottom side real-time flow rate, and the third gain coefficient and the third delay coefficient of the bottom side real-time flow rate. Wherein, the first gain coefficient is the proportionality coefficient of the intensity and direction of the steady-state influence of the real-time feed rate on the temperature of the upper part of the side sampler; the first delay coefficient is the time delay coefficient of the influence of the real-time feed rate change on the temperature of the upper part of the side sampler. The second gain coefficient is a proportionality coefficient of the intensity and direction of the steady-state influence of the steam flow rate setpoint on the temperature of the upper part of the side-mining area; the second delay coefficient is a time delay coefficient of the effect of the change in the steam flow rate setpoint on the temperature of the upper part of the side-mining area. The third gain coefficient is the proportionality coefficient of the intensity and direction of the steady-state influence of the real-time flow rate at the bottom side sampling point on the temperature at the top of the side sampling point; the third delay coefficient is the time delay coefficient of the influence of the real-time flow rate change at the bottom side sampling point on the temperature at the top of the side sampling point. The first gain coefficient, the first delay coefficient, the second gain coefficient, the second delay coefficient, the third gain coefficient, and the third delay coefficient are identified through step response tests or historical data and fitted with an ideal pure time delay model or a first-order inertial plus pure time delay model.

9. The apparatus according to claim 7, characterized in that, The second control module includes: The first control unit is used to perform PID calculations based on the deviation between the real-time temperature of the temperature detection point on the lower left side and the first target control value through the main control loop, and generate the target flow setpoint for small backflow. The second control unit is used to perform PID calculations based on the deviation between the target flow setpoint and the real-time flow of the small return flow through the sub-control loop, and output a control signal to the small return flow control valve to adjust the small return flow. The main control loop and the secondary control loop constitute a cascade control of temperature-small backflow on the lower left side. The output of the main control loop serves as the setpoint for the secondary control loop, and the output of the secondary control loop serves as the control signal for the actuator.

10. An electronic device, characterized in that, It includes a processor, a memory, and a program or instructions stored in the memory and executable on the processor, wherein the program or instructions, when executed by the processor, implement the control method for the diaphragm-type side-collection coarse-distillation tower as described in any one of claims 1-6.

11. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer program instructions, which, when executed by a processor, implement the control method for the diaphragm-type side-collection coarse-distillation tower as described in any one of claims 1-6.

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