Automatic control system for supercritical CO2 release of offshore platform and parameter setting method thereof

Abstract

The application relates to an offshore platform supercritical CO2 release automatic control system and a parameter setting method thereof. The system comprises a release tail pipe, a first flow limiting orifice plate, an electric heater, a temperature sensor, a liquid distribution tank, a nitrogen charging tank, a pressure control valve, a pressure sensor, a bursting disc, a safety release valve, a second flow limiting orifice plate and a control system. The outlet of the release tail pipe is connected to the inlet of the liquid distribution tank in sequence through the first flow limiting orifice plate, the electric heater, the temperature sensor and the pressure sensor. The outlet of the liquid distribution tank is connected to a vent pipe through the second flow limiting orifice plate after being connected to the bursting disc and the safety release valve in parallel. The nitrogen inlet of the liquid distribution tank is connected to the nitrogen charging tank through the pressure control valve. The control system is electrically connected to the temperature sensor, the electric heater, the pressure control valve and the pressure sensor respectively. The application can be widely applied in the offshore oil and gas production field.

Description

Technical Field

[0001] This invention relates to the field of offshore oil and gas production, and in particular to an automatic control system for supercritical CO2 release from offshore platforms and its parameter setting method. Background Technology

[0002] Currently, supercritical CO2 reinjection and storage technology, along with improved recovery rates, is increasingly being applied on offshore platforms. The design of high-pressure CO2 injection manifolds must consider venting issues during fires, maintenance, and other operational conditions. The supercritical CO2 venting process involves complex phase transitions; traditional direct venting methods generate dry ice, and the low-temperature dry ice spraying onto equipment can compromise platform safety, while clogging pipelines can also affect venting safety.

[0003] Currently, in supercritical CO2 venting processes, onshore oil fields and pipelines directly vent CO2 into uninhabited areas, which carries a certain risk of pipe bursts. Venting methods using multi-stage throttling inevitably involve the issue of venting under pressure.

[0004] Therefore, it is necessary to propose a supercritical CO2 release process and set its key process parameters specifically for offshore platforms. To ensure release safety, it is necessary to analyze various operating conditions that may occur during the release process and their impacts, and to quantitatively calculate the reliability of the process parameter design. Furthermore, considering the impact of low-temperature CO2 on personnel, an automated control method for the unmanned release process needs to be considered. Summary of the Invention

[0005] To address the aforementioned problems, the purpose of this invention is to provide an automatic control system for supercritical CO2 venting on offshore platforms and its parameter setting method, which can solve the problem of pressurized venting.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In the first aspect, an automatic control system for supercritical CO2 release on an offshore platform is provided, comprising a release tailpipe, a first flow-limiting orifice plate, an electric heater, a temperature sensor, a liquid separator, a nitrogen pressurization tank, a pressure control valve, a pressure sensor, a rupture disc, a safety release valve, a second flow-limiting orifice plate, and a control system;

[0007] The outlet of the discharge tailpipe is connected to the inlet of the separatory tank in sequence through the first flow-limiting orifice plate, an electric heater, a temperature sensor, and a pressure sensor. The discharge tailpipe is used to receive the fluid flowing in from the high-pressure manifold during the supercritical CO2 discharge process. The separatory tank is used to separate the liquid phase of the fluid during the supercritical CO2 discharge process.

[0008] The outlet of the separator is connected to the vent pipe via the rupture disc and safety relief valve connected in parallel, and then via the second flow limiting orifice plate; the nitrogen inlet of the separator is connected to the nitrogen pressurization tank for pressurizing the nitrogen in the separator via the pressure control valve; the rupture disc is used to open for venting when the safety relief valve cannot be opened and the pressure reaches the opening pressure; the safety relief valve is used to automatically open for venting when the pressure before the valve is higher than the set pressure.

[0009] The control system is electrically connected to the temperature sensor, the electric heater, the pressure control valve, and the pressure sensor respectively. The control system is used to automatically control the power of the electric heater and maintain the pressure of the separatory tank through the pressure control valve based on the temperature collected by the temperature sensor, the pressure collected by the pressure sensor, and the predetermined initial discharge conditions.

[0010] Furthermore, a remote control valve is also provided at the outlet of the discharge tailpipe. The remote control valve is electrically connected to the electric heater and the pressure control valve. The electric heater is turned on based on the opening signal of the remote control valve, and the pressure control valve is turned on based on the closing signal of the remote control valve.

[0011] Furthermore, the high-pressure manifold is equipped with a first shut-off valve and a second shut-off valve. The closing signal of the second shut-off valve is associated with the emergency shut-off ESD signal of the first shut-off valve. The status of the second shut-off valve and the first shut-off valve automatically determines whether the supercritical CO2 venting process is open. When the first shut-off valve and the second shut-off valve are in the closed state, the remote control valve is open. When the first shut-off valve and the second shut-off valve are in the open state, the remote control valve is closed.

[0012] Furthermore, the control system includes a temperature controller, which is electrically connected to the temperature sensor and the electric heater. The temperature controller is equipped with a first data acquisition module and an electric heating control module.

[0013] The first data acquisition module is used to acquire the temperature collected by the temperature sensor and the predetermined initial discharge conditions;

[0014] The electric heating control module is used to automatically control the power of the electric heater based on the temperature collected by the temperature sensor and the predetermined initial discharge conditions, so as to heat the fluid in the discharge tailpipe.

[0015] Furthermore, the control system includes a pressure controller, which is electrically connected to the pressure control valve and the pressure sensor. The pressure controller is equipped with a second data acquisition module and a pressure control module.

[0016] The second data acquisition module is used to acquire the pressure collected by the pressure sensor;

[0017] The pressure control module is used to maintain the pressure of the separatory tank by controlling the pressure control valve when the remote control valve is closed, based on the pressure collected by the pressure sensor.

[0018] Secondly, a parameter setting method for an automatic control system for supercritical CO2 release on an offshore platform is provided, including:

[0019] Based on the actual composition of supercritical CO2 injected from offshore platforms, thermodynamic models were compared and selected, and a tab was generated.

[0020] Based on the generated Tab table, a simulation model of the supercritical CO2 release process of an offshore platform is constructed.

[0021] Based on the simulation results of the constructed model, the design parameters of the automatic control system for supercritical CO2 release on offshore platforms are determined.

[0022] Based on the determined design parameters, multi-condition simulation and process reliability calculations are performed on the constructed model to verify whether the determined design parameters meet the pre-set requirements. If so, the determined design parameters are the design parameters of the automatic control system for supercritical CO2 release on the offshore platform; otherwise, the design parameters are redefined.

[0023] Furthermore, the simulation model of the supercritical CO2 release process of the offshore platform, based on the generated Tab table, includes:

[0024] The high-pressure manifold in the simulation model uses a pressure boundary at its inlet, and the total discharge is simulated by the change in the length of the high-pressure manifold.

[0025] During the total discharge adjustment process, the remote control valve is closed;

[0026] The calculation of the high-pressure manifold inventory is performed under standard conditions to ensure that the target discharge volume is consistent with the integral amount of supercritical CO2 passing through the high-pressure manifold over time, thereby simulating the design discharge volume.

[0027] Implement ESD association between the first shut-off valve and the second shut-off valve;

[0028] The remote control valve is opened when the first and second shut-off valves are in the closed state, thus simulating the venting process.

[0029] Configure the opening status of the remote control valve to be associated with the ESD of the pressure control valve.

[0030] Based on the initial simulated operating conditions, the logic linking the opening state of the remote control valve with the opening state of the electric heater is set to simulate the start-up time of the electric heater.

[0031] Based on the pressure control value of the pressure controller, set the opening pressure of the safety relief valve;

[0032] The opening pressure of the rupture disc is determined based on the design pressure of the vent pipe, and the operating parameters of the safety relief valve and the rupture disc are set in the internal model of the component.

[0033] Furthermore, based on the simulation results of the constructed model, the design parameters of the automatic control system for supercritical CO2 release on the offshore platform are determined, including:

[0034] Sensitivity analysis was performed on the first flow-limiting orifice plate in the direct discharge process to determine the size of the first flow-limiting orifice plate;

[0035] Based on the dimensions of the rupture disc and the safety relief valve, and adhering to the principle that the lowest discharge temperature in the pipeline during the discharge process should not be lower than the dry ice generation temperature, the dimensions of the second flow-limiting orifice plate are determined.

[0036] Determine the pressure control value of the pressure controller based on the pressure system of the nitrogen pressurization tank;

[0037] The start-up conditions for the electric heater are based on the initial discharge temperature and insufficient charging pressure. The power of the electric heater is determined by simulation results under the maximum discharge and most unfavorable operating conditions.

[0038] Thirdly, a processing device is provided, including computer program instructions, wherein when the computer program instructions are executed by the processing device, they are used to implement the steps corresponding to the parameter setting method of the above-mentioned automatic control system for supercritical CO2 release on offshore platforms.

[0039] Fourthly, a computer-readable storage medium is provided, wherein computer program instructions are stored on the computer-readable storage medium, wherein when the computer program instructions are executed by a processor, they are used to implement the steps corresponding to the parameter setting method of the above-mentioned automatic control system for supercritical CO2 release on offshore platforms.

[0040] The present invention has the following advantages due to the adoption of the above technical solutions:

[0041] 1. This invention can achieve unmanned automatic venting by designing and adjusting the process flow parameters during the venting process, ensuring that no dry ice is generated in the venting pipeline during the venting process, and that the system is depressurized at the end of the venting process, thereby improving the safety of the venting process.

[0042] 2. This invention comprehensively considers various normal and abnormal operating conditions in the venting process, and verifies the design parameters through multi-condition process simulation, thereby improving the reliability of traditional design methods.

[0043] 3. This invention can determine the values ​​of key design parameters and process parameters of the system through dynamic simulation based on the release conditions, and can be applied to the design of release systems for various supercritical CO2 and high CO2 offshore oil and gas fields.

[0044] 4. This invention takes into account various operating conditions such as temperature and pressure, impurities, discharge volume, and abnormalities of control components during the discharge process. It can quantitatively verify the design reliability of the critical CO2 discharge process system parameters of offshore platforms based on process reliability, thereby improving the reliability of the system.

[0045] 5. The remote control system and control logic designed using this invention can realize unmanned automatic operation of the supercritical CO2 release process, ensuring the safety of personnel during the release process.

[0046] In summary, this invention can be widely applied in the field of offshore oil and gas production. Attached Figure Description

[0047] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings:

[0048] Figure 1 This is a schematic diagram of the system structure provided in an embodiment of the present invention;

[0049] Figure 2 This is a schematic diagram of a method flow provided in an embodiment of the present invention. Detailed Implementation

[0050] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0051] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0052] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0053] The automatic control system for supercritical CO2 release on offshore platforms and its parameter setting method provided in this embodiment of the invention can achieve unmanned automatic release by designing and setting parameters for the process flow during the release process, ensuring that no dry ice is generated in the release pipeline during the release process, thus improving the safety of the release process. Furthermore, the parameter setting method of this embodiment comprehensively considers various normal and abnormal operating conditions in the release process, and verifies the set parameters through multi-condition process simulation, thereby improving the reliability of the method.

[0054] Example 1

[0055] like Figure 1 As shown, this embodiment provides an automatic control system for supercritical CO2 release on an offshore platform, including a release tailpipe 1, a remote control valve 2, a first flow limiting orifice plate 3, an electric heater 4, a temperature sensor 5, a pressure sensor 6, a liquid separator 7, a pressure control valve 8, a nitrogen pressurization tank 9, a rupture disc 10, a safety release valve 11, a second flow limiting orifice plate 12, a vent pipe 13, a temperature controller 14, and a pressure controller 15.

[0056] The inlet of the vent tailpipe 1 is connected to a high-pressure manifold 18 equipped with a first shut-off valve 16 and a second shut-off valve 17. The closing signal of the second shut-off valve 2 is associated with the emergency shut-off ESD signal of the first shut-off valve 3 to ensure the safety of the high-pressure manifold 18. The status of the second shut-off valve 2 and the first shut-off valve 3 automatically determines whether the supercritical CO2 venting process is open. The vent tailpipe 1 is used to receive the fluid flowing into the high-pressure manifold 18 during the supercritical CO2 venting process.

[0057] The outlet of the vent pipe 1 is connected to the inlet of the separatory tank 7 via a remote control valve 2, a first flow-limiting orifice plate 3, an electric heater 4, a temperature sensor 5, and a pressure sensor 6. The remote control valve 2 is activated by the venting trigger logic of the remote controller, opening when the first shut-off valve 16 and the second shut-off valve 17 are closed, and closing when they are open, thus achieving remote opening or closing. The first flow-limiting orifice plate 3 controls the venting rate. The temperature sensor 5 collects the temperature at the inlet of the separatory tank 7. The separatory tank 7 separates the liquid phase of the fluid during the supercritical CO2 venting process, providing the fluid temperature entering the vent pipe 13 through the separation of the low-temperature liquid phase and the high-temperature gas phase within the gas-liquid two-phase region. The pressure sensor 6 collects the pressure at the inlet of the separatory tank 7.

[0058] The nitrogen inlet of the separator 7 is connected to the nitrogen pressurization tank 9 through the pressure control valve 8. The nitrogen pressurization tank 9 is used to pressurize the nitrogen in the separator 7 to ensure that the pressure in the separator 7 is not lower than the preset value. After the release process begins, the nitrogen pressurization tank 9 is closed to ensure that there is no pressure at the end of the release.

[0059] The outlet of the separator 7 is connected to a vent pipe 13 via a rupture disc 10 and a safety relief valve 11 connected in parallel, and then via a second flow-limiting orifice plate 12. The rupture disc 10 is used to open when the safety relief valve 11 fails to open due to a malfunction and the pressure reaches the opening pressure of the rupture disc 10, thus completing the venting process. The safety relief valve 11 is used to automatically open for venting when the pressure before the valve is higher than the set pressure, and to automatically close when the pressure before the valve is lower than or equal to atmospheric pressure. The second flow-limiting orifice plate 12 is used to control the venting rate, and the vent pipe 13 is used to discharge the gas into the atmosphere.

[0060] Temperature controller 14 is electrically connected to temperature sensor 5 and electric heater 4. Electric heater 4 is also electrically connected to remote control valve 2. Electric heater 4 is used to open based on the opening signal of remote control valve 2 and a predetermined initial discharge condition to heat the fluid in discharge tailpipe 1. Temperature controller 14 is used to automatically control the power of electric heater 4 according to the temperature collected by temperature sensor 5 and the predetermined initial discharge condition.

[0061] The pressure controller 15 is electrically connected to the pressure control valve 8 and the pressure sensor 6. The pressure control valve 8 is also electrically connected to the remote control valve 2. The pressure control valve 8 is used to operate based on the closing signal of the remote control valve 2 and the control signal of the pressure controller 15. The pressure controller 15 is used to maintain the pressure of the separator 7 by controlling the pressure control valve 8 based on the pressure collected by the pressure sensor 6 when the remote control valve 2 is in the closed state.

[0062] In a preferred embodiment, the temperature controller 14 includes a first data acquisition module and an electric heating control module. The first data acquisition module acquires the temperature collected by the temperature sensor 5 and a predetermined initial discharge condition. The electric heating control module automatically controls the power of the electric heater 4 based on the temperature collected by the temperature sensor 5 and the predetermined initial discharge condition to heat the fluid in the discharge tailpipe 1.

[0063] In a preferred embodiment, the pressure controller 15 is provided with a second data acquisition module and a pressure control module. The second data acquisition module is used to acquire the pressure collected by the pressure sensor 6, and the pressure control module is used to maintain the pressure of the separator 7 by controlling the pressure control valve 8 based on the pressure collected by the pressure sensor 6, when the remote control valve 2 is in the closed state.

[0064] In a preferred embodiment, the dimensions of the first flow-limiting orifice plate 3 and the second flow-limiting orifice plate 12, the pressure setting of the nitrogen pressurization tank 9, the pressure control value of the pressure controller 15, the opening pressure of the safety relief valve 11, and the dimensions of the rupture disc 10 are all determined based on dynamic simulation and process reliability analysis.

[0065] Specifically, the size of the first flow-limiting orifice plate 3 is selected through a sensitivity analysis of the first flow-limiting orifice plate 3 in the direct discharge process. The sensitivity analysis includes three dimensions: pressure drop rate, peak discharge volume, and temperature drop rate. More specifically, the size of the first flow-limiting orifice plate 3 can control the peak discharge flow rate during the discharge process and provide sufficient heating time for the electric heater 4. Therefore, it is preferably within the range of 10 to 30 mm.

[0066] Specifically, the pressure setting of the nitrogen pressurization tank 9 is obtained based on the phase analysis of the injected fluid components combined with dynamic simulation.

[0067] Specifically, the pressure control value of the pressure controller 15 is selected between 0.5 and 2 MPa according to the pressure system of the nitrogen pressurization tank 9.

[0068] Specifically, the opening pressure of the safety relief valve 11 is not less than 1.1 times the pressure of the nitrogen pressurization tank 9.

[0069] Specifically, the dimensions of the second flow-limiting orifice plate 12 are determined through dynamic simulation based on the temperature behind the second flow-limiting orifice plate 12 and the minimum discharge temperature at the outlet of the vent pipe 13. More specifically, the dimensions of the second flow-limiting orifice plate 12 affect the minimum discharge temperature in the pipeline during the discharge process, and can be determined comprehensively based on the dimensions of the rupture disc 10 and the safety relief valve 11, preferably within the range of 10 to 30 mm.

[0070] Specifically, the size of the rupture disc 10 is determined by the minimum temperature inside the relief tailpipe 1 during the dynamic simulation of the abnormal working condition where the safety relief valve 11 cannot be opened normally. The minimum temperature inside the relief tailpipe 1 should be 2 to 3 degrees Celsius higher than the dry ice generation temperature.

[0071] In a preferred embodiment, both the temperature controller 14 and the pressure controller 15 are PID controllers.

[0072] In a preferred embodiment, the start-up conditions of the electric heater 4 are based on the initial discharge condition and insufficient charging condition, and the power of the electric heater 4 is determined by simulation results under the maximum discharge and the most unfavorable conditions.

[0073] Example 2

[0074] like Figure 2 As shown in the figure, this embodiment provides a parameter setting method for an automatic control system for supercritical CO2 release on an offshore platform, including the following steps:

[0075] 1) Based on the actual composition of supercritical CO2 injected from offshore platforms, thermodynamic models were compared and selected, and a tab was generated, specifically as follows:

[0076] 1.1) Using the Multiflash thermodynamic calculation software, the physical properties and phase diagrams were compared and selected, taking into account the polar and non-polar impurities that may be contained in the actual composition of supercritical CO2 injected from the offshore platform.

[0077] 1.2) Based on the fluctuation range of impurity component content in the actual composition of supercritical CO2 injected from offshore platforms, different thermodynamic models are established, and the thermodynamic models are compared and selected based on the physical properties and phase diagrams to determine the required thermodynamic model.

[0078] Specifically, different thermodynamic models are selected for different components. For some components, the phase diagram can be used to find that the calculation results do not converge. Therefore, it is necessary to use the phase diagram to determine the usability of the thermodynamic model.

[0079] Specifically, the thermodynamic model can be a cubic equation of state (PRA), a multi-parameter equation of state (CSMA), or GERG-2008. The thermodynamic models are comprehensively compared and selected based on factors such as model convergence, critical points, and density / viscosity calculation results to determine the most suitable model.

[0080] 1.3) Using the required thermodynamic model, based on the initial release temperature and pressure, mark the possible pressure range during the release process and generate a tab for use by the simulation software.

[0081] 2) Using Kspice dynamic simulation software, based on the automatic control system for supercritical CO2 release on the offshore platform in Example 1 and the generated tabs, a simulation model of the supercritical CO2 release process on the offshore platform was constructed, specifically as follows:

[0082] 2.1) In the simulation model of the supercritical CO2 release process of the offshore platform, the inlet of the high-pressure manifold 18 adopts the pressure boundary, and the total release volume is simulated by the change in the length of the high-pressure manifold 18.

[0083] 2.2) During the total discharge adjustment process, close the remote control valve 2.

[0084] 2.3) The system is switched to standard condition using the FlashCalculator module in the Kspice dynamic simulation software. The pipe stock of high-pressure manifold 18 is calculated using the integral module in the Kspice dynamic simulation software to ensure that the target discharge amount is consistent with the integral amount of supercritical CO2 passing through high-pressure manifold 18 over time, thereby simulating the design discharge amount.

[0085] 2.4) The ESD association between the first shut-off valve 16 and the second shut-off valve 17 is implemented through the logic module in the Kspice dynamic simulation software. The control logic judgment during the venting process is implemented by defining relevant variables and writing the judgment logic in the STEP module of the Kspice dynamic simulation software.

[0086] 2.5) The remote control valve 2 is triggered to open when the first shut-off valve 16 and the second shut-off valve 17 are in the closed state, thereby simulating the venting process.

[0087] 2.6) Set the opening status of remote control valve 2 to be associated with the ESD of pressure control valve 8.

[0088] 2.7) Based on the initial simulation conditions, set the association logic between the opening state of the remote control valve 2 and the opening state of the electric heater 4 in the STEP module of the Kspice dynamic simulation software, and simulate the start-up time of the electric heater 4 through the TIME module of the Kspice dynamic simulation software.

[0089] 2.8) The opening pressure of the safety relief valve 11 is 1.1 to 1.2 times the pressure control value of the pressure controller 15, and it closes when the pressure is less than or equal to atmospheric pressure.

[0090] 2.9) The opening pressure of the rupture disc 10 is determined based on the design pressure of the vent pipe 13. The operating parameters of the safety relief valve 11 and the rupture disc 10 are set in the internal model of the assembly.

[0091] 3) Based on the simulation results of the constructed model (including the total discharge volume of the automatic control system for supercritical CO2 release on the offshore platform), determine the design parameters of the automatic control system for supercritical CO2 release on the offshore platform, including the dimensions of the first flow-limiting orifice plate 3 and the second flow-limiting orifice plate 12, the pressure control value of the pressure controller 15, the power and opening conditions of the electric heater 4, specifically:

[0092] 3.1) Perform sensitivity analysis on the first flow limiting orifice plate 3 in the direct discharge process to determine the size of the first flow limiting orifice plate 3.

[0093] Specifically, the size of the first flow-limiting orifice plate 3 can control the peak discharge flow rate during the discharge process, providing sufficient heating time for the electric heater 4.

[0094] 3.2) Based on the dimensions of the rupture disc 10 and the safety relief valve 11, and in accordance with the principle that the lowest relief temperature in the pipeline during the relief process should not be lower than the dry ice generation temperature, the dimensions of the second flow limiting orifice plate 12 are determined. The dimensions of the second flow limiting orifice plate 12 affect the lowest relief temperature in the pipeline during the relief process.

[0095] 3.3) Determine the pressure control value of the pressure controller 15 based on the pressure system of the nitrogen pressurization tank 9.

[0096] 3.4) The starting conditions for electric heater 4 are the initial discharge temperature and insufficient charging pressure. The power of electric heater 4 is determined by the simulation results under the maximum discharge and the most unfavorable operating conditions.

[0097] 4) Based on the determined design parameters, perform multi-condition simulations on the constructed model.

[0098] Specifically, the simulated operating conditions of the venting process include the following: venting process adaptability analysis for initial pressure, temperature and pipe length design changes of 20% in the high-pressure manifold 18; venting process adaptability analysis for supercritical CO2 polar and non-polar impurity content; venting process adaptability analysis for the opening of the abnormal rupture disc 10 of the safety venting valve 11 under abnormal operating conditions; venting process adaptability analysis for insufficient nitrogen pressure in the nitrogen pressurization tank 9; and venting process adaptability analysis for the size drift of the flow-limiting orifice plate.

[0099] 5) Based on the results of multi-condition simulation, the probability of change of design parameters and the probability of failure of components and equipment determined by MCS simulation are used to perform process reliability calculation (reliability calculation for the release process without generating dry ice), identify the weak links in the supercritical CO2 release process system, and check whether the determined design parameters meet the preset requirements. If so, the determined design parameters are the design parameters of the offshore platform supercritical CO2 release automatic control system; otherwise, proceed to step 3) to redetermine the design parameters.

[0100] Example 3

[0101] This embodiment provides a processing device corresponding to the parameter setting method of the automatic control system for supercritical CO2 release on offshore platforms provided in Embodiment 1. The processing device can be applied to client processing devices, such as mobile phones, laptops, tablets, desktop computers, etc., to execute the method of Embodiment 1.

[0102] The processing device includes a processor, a memory, a communication interface, and a bus. The processor, memory, and communication interface are connected via the bus to enable communication between them. The memory stores computer programs that can run on the processing device. When the processing device runs the computer program, it executes the parameter setting method of the automatic control system for supercritical CO2 release on offshore platforms provided in Embodiment 1.

[0103] In some implementations, the memory may be high-speed random access memory (RAM), and may also include non-volatile memory, such as at least one disk storage device.

[0104] In other implementations, the processor can be any type of general-purpose processor, such as a central processing unit (CPU) or a digital signal processor (DSP), and there is no limitation here.

[0105] Furthermore, the logical instructions in the aforementioned memory can be implemented as software functional units and sold or used as independent products, and can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0106] Those skilled in the art will understand that the structure of the above-described computing device is only a partial structure related to the solution of this application and does not constitute a limitation on the computing device to which the solution of this application is applied. A specific computing device may include more or fewer components, or combine certain components, or have different component arrangements.

[0107] Example 4

[0108] This embodiment provides a computer program product corresponding to the parameter setting method of the automatic control system for supercritical CO2 release on offshore platforms provided in Embodiment 1. The computer program product may include a computer-readable storage medium on which computer-readable program instructions are loaded for executing the parameter setting method of the automatic control system for supercritical CO2 release on offshore platforms described in Embodiment 1.

[0109] A computer-readable storage medium can be a tangible device that holds and stores instructions for use by an instruction execution device. A computer-readable storage medium can be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination thereof.

[0110] The computer-readable storage medium provided in the above embodiments has a similar implementation principle and technical effect to the above method embodiments, and will not be described again here.

[0111] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of 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, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0112] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0113] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0114] The above embodiments are only used to illustrate the present invention. The structure, connection method and manufacturing process of each component can be varied. All equivalent transformations and improvements made on the basis of the technical solution of the present invention should not be excluded from the protection scope of the present invention.

Claims

1. A parameter setting method for an automatic control system for supercritical CO2 release on an offshore platform, characterized in that, include: Based on the actual composition of supercritical CO2 injected from offshore platforms, thermodynamic models were compared and selected, and a tab was generated. Based on the generated Tab table, a simulation model of the supercritical CO2 release process of an offshore platform is constructed. Based on the simulation results of the constructed model, the design parameters of the automatic control system for supercritical CO2 release on offshore platforms are determined. Based on the determined design parameters, multi-condition simulation and process reliability calculations are performed on the constructed model to verify whether the determined design parameters meet the pre-set requirements. If so, the determined design parameters are the design parameters of the automatic control system for supercritical CO2 release on the offshore platform; otherwise, the design parameters are redefined. The design parameters for the automatic control system for supercritical CO2 release on offshore platforms are determined based on the simulation results of the constructed model, including: Sensitivity analysis was performed on the first flow-limiting orifice plate in the direct discharge process to determine the size of the first flow-limiting orifice plate; Based on the dimensions of the rupture disc and the safety relief valve, and adhering to the principle that the lowest discharge temperature in the pipeline during the discharge process should not be lower than the dry ice generation temperature, the dimensions of the second flow-limiting orifice plate are determined. Determine the pressure control value of the pressure controller based on the pressure system of the nitrogen pressurization tank; The start-up conditions for the electric heater are based on the initial discharge temperature and insufficient charging pressure. The power of the electric heater is determined by simulation results under the maximum discharge and most unfavorable operating conditions. The automatic control system for supercritical CO2 release on the offshore platform includes a release tailpipe, a first flow-limiting orifice plate, an electric heater, a temperature sensor, a liquid separator, a nitrogen pressurization tank, a pressure control valve, a pressure sensor, a rupture disc, a safety release valve, a second flow-limiting orifice plate, and a control system. The outlet of the discharge tailpipe is connected to the inlet of the separatory tank in sequence through the first flow-limiting orifice plate, an electric heater, a temperature sensor, and a pressure sensor. The discharge tailpipe is used to receive the fluid flowing in from the high-pressure manifold during the supercritical CO2 discharge process. The separatory tank is used to separate the liquid phase of the fluid during the supercritical CO2 discharge process. The outlet of the separator is connected to a vent pipe via the rupture disc and safety relief valve connected in parallel, and then via the second flow-limiting orifice plate; the nitrogen inlet of the separator is connected to a nitrogen pressurization tank for pressurizing the nitrogen in the separator via the pressure control valve; the rupture disc is used to open for venting when the safety relief valve cannot be opened and the pressure reaches the opening pressure; the safety relief valve is used to automatically open for venting when the pressure before the valve is higher than the set pressure. The control system is electrically connected to the temperature sensor, the electric heater, the pressure control valve, and the pressure sensor respectively. The control system is used to automatically control the power of the electric heater and maintain the pressure of the separatory tank through the pressure control valve based on the temperature collected by the temperature sensor, the pressure collected by the pressure sensor, and the predetermined initial discharge conditions. A remote control valve is also provided at the outlet of the discharge tailpipe. The remote control valve is electrically connected to the electric heater and the pressure control valve. The electric heater is turned on based on the opening signal of the remote control valve, and the pressure control valve is turned on based on the closing signal of the remote control valve.

2. The parameter setting method for an automatic control system for supercritical CO2 release on an offshore platform as described in claim 1, characterized in that, The simulation model of the supercritical CO2 release process on the offshore platform, based on the generated tab table, includes: The high-pressure manifold in the simulation model uses a pressure boundary at its inlet, and the total discharge is simulated by the change in the length of the high-pressure manifold. During the total discharge adjustment process, the remote control valve is closed; The calculation of the high-pressure manifold inventory is performed under standard conditions to ensure that the target discharge volume is consistent with the integral amount of supercritical CO2 passing through the high-pressure manifold over time, thereby simulating the design discharge volume. Implement ESD association between the first shut-off valve and the second shut-off valve; The remote control valve is opened when the first and second shut-off valves are in the closed state, thus simulating the venting process. Configure the opening status of the remote control valve to be associated with the ESD of the pressure control valve. Based on the initial simulated operating conditions, the logic linking the opening state of the remote control valve with the opening state of the electric heater is set to simulate the start-up time of the electric heater. Based on the pressure control value of the pressure controller, set the opening pressure of the safety relief valve; The opening pressure of the rupture disc is determined based on the design pressure of the vent pipe, and the operating parameters of the safety relief valve and the rupture disc are set in the internal model of the component.

3. A processing device, characterized in that, It includes computer program instructions, wherein when the computer program instructions are executed by a processing device, they are used to implement the steps corresponding to the parameter setting method of the automatic control system for supercritical CO2 release of offshore platforms as described in any one of claims 1-2.

4. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer program instructions, wherein when the computer program instructions are executed by a processor, they are used to implement the steps corresponding to the parameter setting method of the automatic control system for supercritical CO2 release of offshore platforms as described in any one of claims 1-2.

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