Intelligent adjustment device and optimization method for treatment effect of offshore platform three-phase separator

Abstract

The application provides an offshore platform three-phase separator processing effect intelligent adjustment device and an optimization method. The offshore platform three-phase separator processing effect intelligent adjustment device comprises a first flow pipeline, a chemical agent pipeline, a three-phase separator and a control system. The first flow pipeline is suitable for conveying a gas-liquid mixture at an offshore pipeline outlet to the three-phase separator and is provided with an electric heater. The chemical agent pipeline is suitable for conveying a chemical agent to the three-phase separator. The three-phase separator is divided into a first chamber and a second chamber by a weir plate. The bottom of the first chamber is connected with a water phase output pipeline, and the top of the first chamber is connected with a gas phase output pipeline. The bottom of the second chamber is connected with an oil phase output pipeline. The control system is suitable for establishing a calculation model. The application can realize real-time evaluation of the processing capacity of the three-phase separator and optimization control of the operating parameters and the injection amount of the chemical agent through the calculation model of the control system, improve the oil-water separation effect of the three-phase separator and improve the offshore oilfield production.

Description

Technical Field

[0001] This invention relates to the field of marine oil production and processing technology, and in particular to an intelligent adjustment device and optimization method for the processing effect of a three-phase separator on an offshore platform. Background Technology

[0002] Three-phase separators on offshore platforms are key equipment in offshore oil production and processing, and their processing capacity and efficiency directly affect the production capacity of offshore oil fields. Existing process simulation software uses the effect of the three-phase separator as an input variable, and cannot calculate and optimize the separation effect based on the throughput and process operating conditions.

[0003] Three-phase separator design often relies on experimental data to determine residence time and parameter settings. However, in actual field operation, factors such as oil emulsification and gas-liquid flow characteristics lead to deviations between actual separation performance and design values. This is particularly true for high water-cut oilfields, where significant discrepancies exist between experimental and field inspection data, resulting in unreasonable process design parameters such as weir height, water phase level, oil phase level, and oil-water interface. In actual field operation, chemical reagent concentration and temperature settings are determined based on on-site experience. To ensure oil quality meets standards, the injection rate of chemical reagents and heater temperature are often high, impacting the economic viability of platform production. Furthermore, the inability to quickly determine suitable operating parameters after new well access may result in some oil products failing to meet standards. Therefore, it is necessary to establish a separation performance calculation model considering the factors influencing three-phase separator performance and to develop an intelligent adjustment device and optimization method for three-phase separator performance suitable for offshore platforms. Summary of the Invention

[0004] To address at least one of the aforementioned problems, the present invention aims to provide an intelligent adjustment device and optimization method for the processing effect of a three-phase separator on an offshore platform. This device can comprehensively apply on-site process data, experimental data, and process mechanism models to achieve real-time evaluation of the processing capacity of the three-phase separator and optimized control of operating parameters and chemical reagent injection amounts, thereby improving the oil-water separation effect of the three-phase separator and increasing offshore oilfield production.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The first aspect of this invention provides an intelligent adjustment device for the treatment effect of a three-phase separator on an offshore platform, comprising: a first process pipeline, a chemical reagent pipeline, a three-phase separator, and a control system; wherein, the first process pipeline is adapted to transport a gas-liquid mixture from a subsea pipeline outlet to the three-phase separator and is equipped with an electric heater; the chemical reagent pipeline is adapted to transport chemical reagents to the three-phase separator; the three-phase separator is divided into a first chamber and a second chamber by a weir plate; the inlet of the three-phase separator is connected to the first chamber; the bottom of the first chamber is connected to a water phase output pipeline and the top is connected to a gas phase output pipeline; the bottom of the second chamber is connected to an oil phase output pipeline; the control system is adapted to establish a calculation model and is adapted to: collect the temperature data of the material flow in the first process pipeline and then... The power of the electric heater is controlled according to the optimized temperature setpoint to ensure that the temperature of the material entering the three-phase separator reaches the setpoint. The flow rate data of the chemical reagent pipeline is collected, and the flow rate setpoint of the chemical reagent pipeline is obtained through the calculation model based on the output chemical reagent required concentration value. The flow rate of the chemical reagent pipeline is adjusted according to the flow rate setpoint, taking into account future flow fluctuations during the adjustment process. The oil-water interface data and aqueous phase level data in the first chamber and the oil phase level data in the second chamber are collected and corresponding optimization data are obtained through the calculation model. The time lag characteristics are considered during the optimization process, and the oil-water interface, aqueous phase level, oil phase level, and weir height in the three-phase separator are adjusted in real time based on the optimization data.

[0007] For example, in at least one embodiment of the present invention, the intelligent adjustment device for the treatment effect of a three-phase separator on an offshore platform includes a control system comprising a first flow sensor connected to the first process pipeline and adapted to collect material flow data within the first process pipeline.

[0008] For example, in at least one embodiment of the present invention, the intelligent adjustment device for the treatment effect of a three-phase separator on an offshore platform includes a control system that further includes a first temperature sensor and an electric heater power controller that are electrically connected. The first temperature sensor is adapted to collect material temperature data in the first process pipeline, and the electric heater power controller is adapted to control the power of the electric heater.

[0009] For example, in at least one embodiment of the present invention, the intelligent adjustment device for the treatment effect of a three-phase separator on an offshore platform includes a control system that further includes a first regulating valve disposed in the chemical agent pipeline, a second flow sensor adapted to collect flow data of the material in the chemical agent pipeline, and a first flow controller electrically connected to the second flow sensor and adapted to control the opening of the first regulating valve.

[0010] For example, in at least one embodiment of the present invention, the intelligent adjustment device for the treatment effect of a three-phase separator on a marine platform includes a control system further comprising: a pressure sensor adapted to collect pressure data within the three-phase separator; a boundary sensor adapted to collect oil-water interface data in the first chamber; a first level sensor adapted to collect oil phase level data in the second chamber; a second level sensor adapted to collect water phase level data in the first chamber; a second regulating valve disposed on the gas phase output pipeline; a third regulating valve disposed on the oil phase output pipeline; a fourth regulating valve disposed on the water phase output pipeline; a first pressure controller electrically connected to the pressure sensor and adapted to control the opening of the second regulating valve; a high-selectivity controller electrically connected to the boundary sensor and the first level sensor and adapted to control the opening of the third regulating valve; and a first level controller electrically connected to the second level sensor and adapted to control the opening of the fourth regulating valve.

[0011] For example, in at least one embodiment of the present invention, the intelligent adjustment device for the treatment effect of a three-phase separator on an offshore platform further includes a second process pipeline. The outlet ends of the first process pipeline and the chemical reagent pipeline converge and connect to the inlet end of the second process pipeline. The outlet end of the second process pipeline is connected to the first chamber of the three-phase separator. The second process pipeline is provided with a first sampling point to obtain the component parameters of the stream entering the inlet of the three-phase separator. The oil phase output pipeline is provided with a second sampling point to obtain the component parameters of the stream separated by the three-phase separator.

[0012] For example, in the intelligent adjustment device for the treatment effect of a three-phase separator on an offshore platform provided in at least one embodiment of the present invention, the electric heater power controller, the first flow controller, the first pressure controller, the high-selectivity controller, and the first liquid level controller are all configured as PID controllers; the process of the control system controlling the set value through the output parameters of each PID controller and the process of tuning the parameters of each PID controller are all optimized in association with the treatment capacity and target treatment effect of the three-phase separator.

[0013] For example, in at least one embodiment of the present invention, the intelligent adjustment device for the treatment effect of a three-phase separator on a marine platform is provided. The control system is adapted to: calculate the target control value of the chemical agent injection amount based on the predicted value of the inlet flow of the three-phase separator and the required concentration value obtained based on the calculation model, and control the opening of the first regulating valve based on the target control amount; a model prediction controller is provided outside the first flow controller, and the model prediction controller is adapted to pre-prepare the change trajectory of the target control value of the chemical agent injection amount to ensure the control stability of the first flow controller.

[0014] For example, in the intelligent adjustment device for the treatment effect of a three-phase separator on an offshore platform provided in at least one embodiment of the present invention, the control system is adapted to: obtain the predicted value of the inlet flow of the three-phase separator by performing online training and prediction based on historical data using the LSTM method; the control system is adapted to: tune the proportional and integral parameters of the high-selectivity controller and the first liquid level controller by establishing a three-phase separator flow model during the process of controlling the opening of the third regulating valve through the high-selectivity controller and controlling the opening of the fourth regulating valve through the first liquid level controller.

[0015] A second aspect of this invention provides a method for optimizing the treatment effect of a three-phase separator on an offshore platform, comprising:

[0016] A module for calculating the treatment effect of a three-phase separator is constructed. Specifically, the water content at the oil phase outlet of the three-phase separator is calculated based on experimental data and field test data under different oil conditions, combined with multiple mechanistic models. Depending on whether the initial water content of the oil is greater than the reversal point, CNN method and mechanistic model are used to establish a calculation model for the treatment effect. In the mechanistic model, atomization, sedimentation and collision physical processes are considered, the uncertainty of droplets and process parameters is considered, and the outlet water content is calculated by MCS method.

[0017] The validity of the calculation model for the treatment effect of the three-phase separator was verified and corrected. Specifically, for the data-driven model before the phase reversal point, its conformity to physical laws was verified, and a deviation factor was introduced to correct the accuracy based on a small amount of data obtained by sampling. For the mechanism model after the phase reversal point, the emulsifier effect coefficient and temperature effect coefficient were introduced to correct the model accuracy.

[0018] Based on the calculation model of the treatment effect of the three-phase separator, an optimization function is constructed to minimize the target treatment effect and the calculated value. Various process constraints and upper and lower limits of parameters are used as constraints, and the weir plate height and operating parameters are used as decision variables.

[0019] A two-stage optimization method was adopted to solve the decision variables. In the first stage, the height of the three-phase separator weir was optimized under the current operating conditions and in combination with the long-term design capacity of the oilfield. The optimization period was at least one month. In the second stage, the optimal flow temperature and chemical concentration were solved based on the optimized three-phase separator settings. The pipeline inflow prediction was obtained by online training of the LSTM model using historical data. The optimization period was 30 to 60 minutes.

[0020] The optimized weir height is fed back to the weir height regulator. The liquid level interface setpoint calculated in conjunction with the design specifications is fed back to the high-selection controller and the first liquid level controller as setpoints. The optimized material temperature is fed back to the electric heating power controller. The chemical reagent concentration calculation result is combined with the LSTM model flow prediction calculation to obtain the required flow rate, and after smoothing through the model predictive control method, it is fed back to the first flow controller as a setpoint.

[0021] Because the present invention adopts the above technical solution, it has at least the following advantages:

[0022] I. This invention can optimize relevant process operation parameters by utilizing the geometric parameters, throughput, and target processing effect of the three-phase separator, and automatically feed them back to each controller of the three-phase separator, thereby realizing intelligent adjustment of process parameters related to the separation effect of the three-phase separator, reducing the complexity of operating the three-phase separator on offshore production platforms, and improving the economy and product quality of oil fields.

[0023] Second, this invention can automatically optimize the process parameters of the three-phase separator, such as temperature and demulsifier concentration, as well as the control parameters of the three-phase separator, such as oil-water interface, water phase level and oil phase level, based on the set target processing effect.

[0024] Third, for oilfields with medium and low water cut, the three-phase separator treatment effect was calculated using experimental data and a CNN model to assess the multivariate influencing factors, thus establishing the model's effectiveness based on physical laws.

[0025] Fourth, by integrating multiple flow mechanism models, the problem of calculating the outlet water cut of three-phase separators in high water-cut oilfields was solved.

[0026] Fifth, in the optimization model of the three-phase separator, the moisture content calculation model and process constraints are coupled, and the dual optimization of separation structure parameters and process parameters is achieved through two-stage solution.

[0027] VI. Considering the characteristics of the on-site control process, this invention performs predictive control design and PID parameter tuning for the optimized control value feedback process, solving the stability problem of the optimized operating parameter back-writing process; by taking into account the feed flow fluctuation characteristics of the three-phase separator through the LTSM method, and combining the concentration optimization results, it achieves precise control of the chemical agent concentration. Attached Figure Description

[0028] Figure 1 A schematic diagram of the intelligent adjustment device for the treatment effect of a three-phase separator on an offshore platform provided in at least one embodiment of the present invention;

[0029] Figure 2A flowchart illustrating the method for optimizing the treatment effect of a three-phase separator on an offshore platform, provided in at least one embodiment of the present invention.

[0030] Marked in the attached diagram:

[0031] 1 is the first process pipeline; 2 is the first flow sensor; 3 is the electric heater; 4 is the electric heating power controller; 5 is the first temperature sensor; 6 is the first sampling point; 7 is the chemical reagent pipeline; 8 is the second flow sensor; 9 is the first regulating valve; 10 is the first flow controller; 11 is the second process pipeline; 12 is the three-phase separator; 13 is the interface sensor; 14 is the first liquid level sensor; 15 is the second liquid level sensor; 16 is the weir plate; 17 is the pressure sensor; 18 is the high-selectivity controller; 19 is the first liquid level controller; 20 is the first pressure controller; 21 is the second regulating valve; 22 is the third regulating valve; 23 is the fourth regulating valve; 24 is the second sampling point; 25 is the optimization module; 26 is the chemical reagent concentration calculation module; 27 is the safety relief valve. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0033] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the system or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0034] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "assembly," "setup," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0035] At least one embodiment of the present invention provides an intelligent adjustment device and optimization method for the treatment effect of a three-phase separator on an offshore platform. It can comprehensively apply on-site process data, experimental data and process mechanism models to realize real-time evaluation of the treatment capacity of the three-phase separator and optimized control of operating parameters and chemical reagent injection amount, thereby improving the oil-water separation effect of the three-phase separator and increasing the production of offshore oil fields.

[0036] The intelligent adjustment device and optimization method for the treatment effect of the three-phase separator on the offshore platform provided in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0037] Example 1:

[0038] Reference Figure 1 As shown, this embodiment provides an intelligent adjustment device for the treatment effect of a three-phase separator on an offshore platform, including a first process pipeline 1, a chemical reagent pipeline 7, a three-phase separator 12, and a control system.

[0039] The first process pipeline 1 has its input end connected to the subsea pipeline outlet for inputting the subsea pipeline gas-liquid mixture, and its output end adapted to output the subsea pipeline gas-liquid mixture to the downstream three-phase separator 12. The first process pipeline 1 is equipped with an electric heater 3 to heat the material flowing through it.

[0040] The input end of the chemical reagent line 7 is connected to the chemical reagent tank, and the output end is connected to the output end of the first process line 1, so as to output chemical reagents to mix with the material transported by the first process line 1 and jointly transport them to the downstream three-phase separator 12.

[0041] The three-phase separator 12 is divided into a first chamber and a second chamber by a weir plate 16. The inlet of the three-phase separator 12 is connected to the first chamber, that is, the material entering the three-phase separator 12 first enters the first chamber.

[0042] The three-phase separator 12 has a first chamber with a lower portion suitable for containing the separated aqueous phase, a second chamber with a lower portion suitable for containing the separated oil phase, and a second chamber with an upper portion suitable for containing the separated gas phase. The bottom of the first chamber is connected to an aqueous phase output line, and the top is connected to a gas phase output line. The bottom of the second chamber is connected to an oil phase output line. The aqueous phase output line is suitable for outputting the aqueous phase from the first chamber to a water treatment system, the gas phase output line is suitable for outputting the gas phase from both the first and second chambers to a gas treatment system, and the oil phase treatment system is suitable for outputting the oil phase from the second chamber to an oil treatment system.

[0043] The control system is suitable for establishing a computational model, and is suitable for:

[0044] After collecting the material temperature data in the first process pipeline 1, the model is optimized. The power of the electric heater 3 is controlled according to the optimized temperature setpoint so that the material temperature entering the three-phase separator 12 reaches the setpoint.

[0045] Collect flow data of chemical agent pipeline 7, obtain the flow set value of chemical agent pipeline 7 through calculation model based on the output chemical agent demand concentration value, adjust the flow of chemical agent pipeline 7 according to the flow set value, and consider the future flow fluctuation characteristics in the adjustment process;

[0046] Data on the oil-water interface and water phase level in the first chamber, and the oil phase level in the second chamber are collected. Corresponding optimization data are obtained through a calculation model. During the optimization process, time delay characteristics are considered. Based on the optimization data, the oil-water interface, water phase level, oil phase level, and weir height in the three-phase separator 12 are adjusted in real time.

[0047] Furthermore, in this embodiment, the control system includes a first flow sensor 2, which is disposed in the first process pipeline 1 and is adapted to collect material flow data within the first process pipeline 1.

[0048] Furthermore, in this embodiment, the control system further includes a first temperature sensor 5 and an electric heater power controller 4, which are electrically connected to each other. The first temperature sensor 5 is adapted to collect material temperature data within the first process pipeline 1 and transmit the collected material temperature data within the first process pipeline 1 to the electric heater 3 controller for processing. The electric heater power controller 4 is adapted to control the power of the electric heater 3 to ensure that the material temperature within the first process pipeline 1 reaches a predetermined value.

[0049] Furthermore, in this embodiment, the control system also includes a first regulating valve 9, a second flow sensor 8, and a first flow controller 10. The first regulating valve 9 is disposed on the chemical reagent pipeline 7. The second flow sensor 8 is adapted to collect flow rate data within the chemical reagent pipeline 7. The first flow controller 10 is electrically connected to the second flow sensor 8. The flow rate data collected by the second flow sensor 8 within the chemical reagent pipeline 7 is adapted to be transmitted to the first flow controller 10 for processing. The first flow controller 10 is adapted to control the opening degree of the first regulating valve 9, thereby regulating the output flow rate of the chemical reagent pipeline 7.

[0050] Furthermore, in this embodiment, the control system also includes a pressure sensor 17, a second regulating valve 21, and a first pressure controller 20. The pressure sensor 17 is adapted to collect pressure data within the three-phase separator 12. The second regulating valve 21 is located on the gas phase output pipeline. The first pressure controller 20 is electrically connected to the pressure sensor 17. The pressure data collected by the first pressure sensor 17 within the three-phase separator 12 is adapted to be transmitted to the pressure sensor 17 for processing. The pressure sensor 17 is adapted to control the opening of the second regulating valve 21 to regulate the pressure within the three-phase separator 12 and to regulate the gas phase output flow rate. When the pressure sensor 17 detects that the pressure within the three-phase separator 12 exceeds a set value, it controls the second regulating valve 21 to automatically open for safe release, ensuring that the internal pressure of the three-phase separator 12 does not exceed the set value.

[0051] Furthermore, in this embodiment, the control system also includes a first liquid level sensor 14, a boundary sensor 13, a third regulating valve 22, and a high-selectivity controller 18. The boundary sensor 13 is adapted to collect oil-water boundary data in the first chamber, the first liquid level sensor 14 is adapted to collect oil phase level data in the second chamber, the third regulating valve 22 is located on the oil phase output pipeline, and the high-selectivity controller 18 is electrically connected to the boundary sensor 13 and the first liquid level sensor 14. The oil-water boundary data collected by the boundary sensor 13 and the oil phase level data collected by the first liquid level sensor 14 are both adapted to be transmitted to the high-selectivity controller 18 for processing. The high-selectivity controller 18 is adapted to control the opening degree of the third regulating valve 22 to regulate the oil phase level in the second chamber and the output flow rate of the oil phase.

[0052] Furthermore, in this embodiment, the control system also includes a second liquid level sensor 15, a fourth regulating valve 23, and a first liquid level controller 19. The second liquid level sensor 15 is adapted to collect water phase liquid level data in the first chamber. The fourth regulating valve 23 is disposed on the water phase output pipeline. The first liquid level controller 19 is electrically connected to the second liquid level sensor 15. The water phase liquid level data collected by the second liquid level sensor 15 is adapted to be transmitted to the first liquid level controller 19 for processing. The first liquid level controller 19 is adapted to control the opening degree of the fourth regulating valve 23 to regulate the water phase liquid level in the first chamber and to regulate the output flow rate of the water phase.

[0053] Furthermore, in this embodiment, the intelligent adjustment device for the treatment effect of the three-phase separator on the offshore platform also includes a second process pipeline 11. The outlet ends of the first process pipeline 1 and the chemical agent pipeline 7 converge and connect to the inlet end of the second process pipeline 11, and the outlet end of the second process pipeline 11 is connected to the first chamber of the three-phase separator 12. The material transported by the first process pipeline 1 and the material transported in the chemical agent pipeline 7 converge and enter the second process pipeline 11, and are then input into the first chamber of the three-phase separator 12 via the second process pipeline 11.

[0054] Furthermore, in this embodiment, the second process pipeline 11 is provided with a first sampling point 6 to obtain the material composition parameters entering the inlet of the three-phase separator 12. The material composition parameters entering the inlet of the three-phase separator 12 include, for example, the moisture content of the material composition entering the inlet of the three-phase separator 12.

[0055] Furthermore, in this embodiment, the oil phase output pipeline is equipped with a second sampling point 24 to obtain the component parameters of the stream separated by the three-phase separator 12. The water content of the output oil phase can be tested through the second sampling point and fed back to the control system for parameter correction of the three-phase separator treatment effect calculation model.

[0056] Furthermore, in this embodiment, a flare line is connected to the top of the three-phase separator 12, and the flare line even has a safety relief valve 27 to relieve pressure when the pressure inside the three-phase separator 12 is too high.

[0057] Example 2:

[0058] Based on the intelligent adjustment device for the treatment effect of the three-phase separator on the offshore platform provided in Embodiment 1, in this embodiment, the electric heater power controller 4, the first flow controller 10, the first pressure controller 20, the high-selection controller 18, and the first liquid level controller 19 are all configured as PID (proportional-integral-derivative) controllers.

[0059] Furthermore, in this embodiment, the process of controlling the set value through the output parameters of each PID controller and the process of tuning the parameters of each PID controller are both optimized in relation to the processing capacity and target processing effect of the three-phase separator 12.

[0060] Furthermore, in this embodiment, the control system is adapted to: calculate the target control value of the chemical agent injection amount based on the predicted value of the inlet flow of the three-phase separator 12 and the required concentration value obtained based on the calculation model, and control the opening degree of the first regulating valve 9 based on the target control amount.

[0061] Furthermore, in this embodiment, since the set value of the first flow controller 10 has time-varying characteristics, a model prediction controller is provided outside the first flow controller 10. The model prediction controller is adapted to pre-predict the change trajectory of the target control value of the chemical agent injection amount, so as to ensure the control stability of the first flow controller 10.

[0062] Furthermore, in this embodiment, the control system is adapted to: use LSTM (Long Short-Term Memory Neural Network) method for online training and prediction based on historical data to obtain the predicted value of the inlet flow rate of the three-phase separator 12. The predicted value of the inlet flow rate of the three-phase separator 12 can also be used as process conditions for optimizing temperature and chemical reagent concentration.

[0063] Furthermore, in this embodiment, the control system is adapted to: tune the proportional and integral parameters of the high-selectivity controller 18 and the first level controller 19 by establishing a three-phase separator flow model during the process of controlling the opening of the third regulating valve 22 through the high-selectivity controller 18 and controlling the opening of the fourth regulating valve 23 through the first level controller 19. Further, the tuning model adopts a high-order model containing time delay terms, the model parameters are determined through parameter identification, and the controller parameters are optimized using advanced PID control theory.

[0064] Furthermore, in this embodiment, the temperature setpoint, weir height setting, water phase level, oil phase level, oil-water interface control values, and chemical reagent concentration control values ​​obtained by the control system are obtained by solving an optimization model. Further, the optimization model includes, for example, a calculation model for the water content at the outlet of the three-phase separator 12, calculations for the nozzle impulse of the three-phase separator 12, and calculations of various outlet process specification constraints. Further, an objective function is constructed through a three-phase separator treatment effect calculation model, and the optimal parameter setpoints are solved by combining the specified throughput, the internal pressure of the three-phase separator 12, and the geometric dimensions of the three-phase separator 12. Further, a segmented solution strategy for the weir height and process parameters is adopted in the solution process; that is, the optimal weir height is first determined, and the setpoints for the water phase level, oil phase level, and oil-water interface are calculated according to the design specifications; this part is a long-cycle optimization. Then, based on this, the optimal values ​​for the material temperature and chemical reagent concentration are solved; this part is a short-cycle optimization.

[0065] Furthermore, in this embodiment, the water content calculation model at the outlet of the three-phase separator 12 is coupled with the droplet size calculation model, sedimentation separation model, collision model, and emulsification characterization model to construct a computational theoretical model of the three-phase separator's treatment effect under high water content (initial water content higher than the crude oil's antiphase point). Furthermore, for low water content (initial water content lower than or equal to the crude oil's antiphase point), a separation effect data model is constructed by correlating experimental data with multiple influencing factors.

[0066] Furthermore, the uncertainty of relevant process operating parameters is considered in the high water content mechanism model, and stochastic processes are taken into account in the model solution process.

[0067] Furthermore, the modeling and validity verification process of the low moisture content data model considers the physical laws governing the effects of influencing factors on the separation effect.

[0068] Furthermore, correction coefficients are set in both the mechanistic model and the data model, which can be adjusted according to the deviations in the field experiments.

[0069] Example 3:

[0070] Reference Figure 2As shown, this embodiment provides a method for optimizing the treatment effect of a three-phase separator on an offshore platform, including the following steps S1 to S5:

[0071] S1, Construct a three-phase separator treatment effect calculation module, specifically: Based on experimental data and field test data of oil under different working conditions, combined with multiple mechanism models, calculate the water content of the oil phase outlet of the three-phase separator. Depending on whether the initial water content of the oil is greater than the antiphase point, establish treatment effect calculation models using CNN (convolutional neural network) method and mechanism model respectively. In the mechanism model, atomization, sedimentation and collision physical processes are considered, the uncertainty of droplets and process parameters is considered, and the outlet water content is calculated by MCS (Monte Carlo simulation) method.

[0072] S2, verify and correct the effectiveness of the three-phase separator treatment effect calculation model. Specifically, for the data-driven model before the phase reversal point, verify its conformity to physical laws and introduce a deviation factor to correct the accuracy based on a small amount of data obtained by sampling. For the mechanism model after the phase reversal point, introduce the emulsifier action coefficient and temperature action coefficient to correct the model accuracy.

[0073] S3, based on the calculation model of the treatment effect of the three-phase separator, constructs an optimization function that minimizes the target treatment effect and the calculated value. It uses various process constraints and upper and lower limits of parameters as constraints, and takes the weir height and operating parameters (such as material temperature and chemical reagent concentration) as decision variables.

[0074] S4 employs a two-stage optimization method to solve for decision variables. In the first stage, under the current operating conditions, the height of the three-phase separator weir is optimized in conjunction with the long-term design capacity of the oilfield. This optimization cycle is at least one month. In the second stage, the optimal flow temperature and chemical concentration are solved based on the optimized three-phase separator settings. The pipeline inflow prediction is obtained by online training of historical data using an LSTM model. The optimization cycle is 30 to 60 minutes.

[0075] S5, the weir plate height optimization result is fed back to the weir plate height adjuster, and the liquid level interface set value obtained by combining the design specifications is fed back to the high-selection controller and the first liquid level controller as the set value. The material temperature optimization result is fed back to the electric heating power controller. The chemical agent concentration calculation result is combined with the LSTM model flow prediction calculation to obtain the demand flow rate, and after smoothing through the model prediction control method, it is fed back to the first flow controller as the set value.

[0076] It should be noted that, in the embodiments of the present invention, if the initial water content of the three-phase separator stream is higher than the reversal point of the crude oil, it is considered a high water content condition; if the initial water content is lower than or equal to the reversal point of the crude oil, it is considered a medium to low water content condition.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A smart adjustment device for the treatment effect of a three-phase separator on an offshore platform, characterized in that, include: The first process pipeline, chemical reagent pipeline, three-phase separator, and control system; The first process pipeline is adapted to transport a gas-liquid mixture from the subsea pipeline outlet to the three-phase separator and is equipped with an electric heater. The chemical reagent pipeline is adapted to transport chemical reagents to the three-phase separator. The three-phase separator is divided into a first chamber and a second chamber by a weir plate. The inlet of the three-phase separator is connected to the first chamber. The bottom of the first chamber is connected to a water phase output pipeline, and the top is connected to a gas phase output pipeline. The bottom of the second chamber is connected to an oil phase output pipeline. The control system is adapted to establish a calculation model and is adapted to: After collecting the material temperature data in the first process pipeline, the data is optimized through a calculation model. The power of the electric heater is controlled according to the optimized temperature setpoint so that the material temperature entering the three-phase separator reaches the setpoint. The flow rate data of the chemical agent pipeline is collected, and the set value of the chemical agent pipeline flow rate is obtained through a calculation model based on the output chemical agent required concentration value. The flow rate of the chemical agent pipeline is adjusted according to the set value, and the characteristics of future flow fluctuations are taken into account during the adjustment process. Data on the oil-water interface and water phase level in the first chamber and the oil phase level in the second chamber are collected and corresponding optimization data are obtained through a calculation model. During the optimization process, time delay characteristics are considered, and the oil-water interface, water phase level, oil phase level and weir height in the three-phase separator are adjusted in real time according to the optimization data. The control system includes a first flow sensor, which is connected to the first process pipeline and is adapted to collect material flow data within the first process pipeline. The control system further includes a first temperature sensor and an electric heater power controller that are electrically connected. The first temperature sensor is adapted to collect material temperature data in the first process pipeline, and the electric heater power controller is adapted to control the power of the electric heater. The control system further includes a first regulating valve disposed in the chemical agent pipeline, a second flow sensor adapted to collect flow data of the chemical agent pipeline, and a first flow controller electrically connected to the second flow sensor and adapted to control the opening of the first regulating valve. The control system further includes: The system includes a pressure sensor suitable for collecting pressure data within the three-phase separator, a boundary sensor suitable for collecting oil-water interface data in the first chamber, a first level sensor suitable for collecting oil phase level data in the second chamber, a second level sensor suitable for collecting water phase level data in the first chamber, a second regulating valve disposed on the gas phase output pipeline, a third regulating valve disposed on the oil phase output pipeline, a fourth regulating valve disposed on the water phase output pipeline, a first pressure controller electrically connected to the pressure sensor and suitable for controlling the opening of the second regulating valve, a high-selectivity controller electrically connected to the boundary sensor and the first level sensor and suitable for controlling the opening of the third regulating valve, and a first level controller electrically connected to the second level sensor and suitable for controlling the opening of the fourth regulating valve. The intelligent adjustment device for the treatment effect of the three-phase separator on the offshore platform can execute the following optimization method for the treatment effect of the three-phase separator on the offshore platform: A module for calculating the treatment effect of a three-phase separator is constructed. Specifically, the water content at the oil phase outlet of the three-phase separator is calculated based on experimental data and field test data under different oil conditions, combined with multiple mechanistic models. Depending on whether the initial water content of the oil is greater than the reversal point, CNN method and mechanistic model are used to establish a calculation model for the treatment effect. In the mechanistic model, atomization, sedimentation and collision physical processes are considered, the uncertainty of droplets and process parameters is considered, and the outlet water content is calculated by MCS method. The validity of the calculation model for the treatment effect of the three-phase separator was verified and corrected. Specifically, for the data-driven model before the phase reversal point, its conformity to physical laws was verified, and a deviation factor was introduced to correct the accuracy based on a small amount of data obtained by sampling. For the mechanism model after the phase reversal point, the emulsifier effect coefficient and temperature effect coefficient were introduced to correct the model accuracy. Based on the calculation model of the treatment effect of the three-phase separator, an optimization function is constructed to minimize the target treatment effect and the calculated value. Various process constraints and upper and lower limits of parameters are used as constraints, and the weir plate height and operating parameters are used as decision variables. A two-stage optimization method was adopted to solve the decision variables. In the first stage, the height of the three-phase separator weir was optimized under the current operating conditions and in combination with the long-term design capacity of the oilfield. The optimization period was at least one month. In the second stage, the optimal flow temperature and chemical concentration were solved based on the optimized three-phase separator settings. The pipeline inflow prediction was obtained by online training of the LSTM model using historical data. The optimization period was 30 to 60 minutes. The optimized weir height is fed back to the weir height regulator. The liquid level interface setpoint calculated in conjunction with the design specifications is fed back to the high-selection controller and the first liquid level controller as setpoints. The optimized material temperature is fed back to the electric heating power controller. The chemical reagent concentration calculation result is combined with the LSTM model flow prediction calculation to obtain the required flow rate, and after smoothing through the model predictive control method, it is fed back to the first flow controller as a setpoint.

2. The intelligent adjustment device for the treatment effect of the three-phase separator on an offshore platform according to claim 1, characterized in that, The intelligent adjustment device for the treatment effect of the three-phase separator on the offshore platform also includes a second process pipeline. The outlet ends of the first process pipeline and the chemical agent pipeline are connected to the inlet end of the second process pipeline, and the outlet end of the second process pipeline is connected to the first chamber of the three-phase separator. The second process pipeline is equipped with a first sampling point to obtain the component parameters of the stream entering the inlet of the three-phase separator, and the oil phase output pipeline is equipped with a second sampling point to obtain the component parameters of the stream separated by the three-phase separator.

3. The intelligent adjustment device for the treatment effect of the three-phase separator on an offshore platform according to claim 2, characterized in that, The electric heater power controller, the first flow controller, the first pressure controller, the high-selectivity controller, and the first liquid level controller are all configured as PID controllers; The process of controlling the set value through the output parameters of each PID controller and the process of tuning the parameters of each PID controller are both optimized in relation to the processing capacity and target processing effect of the three-phase separator.

4. The intelligent adjustment device for the treatment effect of the three-phase separator on an offshore platform according to claim 3, characterized in that, The control system is adapted to: calculate the target control value of the chemical agent injection amount based on the predicted value of the inlet flow of the three-phase separator and the required concentration value obtained based on the calculation model, and control the opening of the first regulating valve based on the target control amount; The first flow controller is equipped with a model predictive controller, which is adapted to predict the change trajectory of the target control value of the chemical agent injection amount to ensure the control stability of the first flow controller.

5. The intelligent adjustment device for the treatment effect of the three-phase separator on an offshore platform according to claim 4, characterized in that, The control system is adapted to: use the LSTM method to perform online training and prediction based on historical data to obtain the predicted value of the inlet flow of the three-phase separator; The control system is adapted to: in the process of controlling the opening of the third regulating valve through the high-selectivity controller and controlling the opening of the fourth regulating valve through the first liquid level controller, to tune the proportional and integral parameters of the high-selectivity controller and the first liquid level controller by establishing a three-phase separator flow model.

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