Parallel fused salt heating superheated steam generation system and control method thereof

Abstract

The embodiment of the invention provides a parallel type fused salt heating superheated steam generation system and a control method thereof, and belongs to the technical field of oil field steam injection. The system comprises an evaporator system and a superheater system which are connected in sequence, and the evaporator system and the superheater system are combined to be used for treating oilfield produced water into corresponding steam required by steam injection; the control module is used for constructing a corresponding salt supply linkage model based on the real-time operation condition so as to generate an optimal fused salt supply device joint control scheme meeting the steam injection demand condition based on the salt supply linkage model; and the execution modules are arranged on salt supply pipelines of the fused salt supply devices of the evaporator system and the superheater system correspondingly and used for executing fused salt supply amount adjustment based on the optimal fused salt supply device joint control scheme. According to the scheme, molten salt consumption is reduced, the problems that in the prior art, the salt supply proportion is not coordinated, and steam quality fluctuates are solved, the dynamic response capacity of a steam injection system is greatly improved, and a more efficient solution is provided for thickened oil recovery.

Description

Technical Field

[0001] The invention relates to the technical field of oil field steam injection, and in particular to a parallel molten salt heated superheated steam generating system and a parallel molten salt heated superheated steam generating system control method. Background Art

[0002] In the steam injection production of heavy oil fields, the precise generation of wet saturated steam and superheated steam is the key to achieving efficient oil production. However, the existing steam injection system generally adopts a separate design, that is, the evaporator system and the superheater system operate independently, and each provides heat source through a separate molten salt supply device. Although this design can meet basic needs under certain specific working conditions, it has significant deficiencies in overall system energy efficiency optimization and stability.

[0003] First, the existing scheme lacks linkage control in the molten salt supply process of the evaporator system and the superheater system. Since the two systems operate independently, their molten salt supply can only be adjusted by a separate control algorithm, which makes it difficult to dynamically optimize the salt supply ratio according to actual operating needs. It is often the case that the superheated steam temperature or the wet saturated steam dryness cannot meet the target requirements at the same time. This separate control method limits the overall dynamic response capability of the system, increases the consumption of molten salt, and thus reduces the operating efficiency.

[0004] Secondly, the existing scheme does not realize centralized management of cold salt recovery and hot salt distribution. The reheating process after cold salt recovery lacks stability due to the fluctuation of return salt flow, which further affects the stability of steam quality. Especially in the case of large load fluctuations or complex produced water quality, a separate molten salt supply device is difficult to coordinate the salt supply demand of the evaporator and superheater, which easily leads to fluctuations in steam quality or system overload.

[0005] In view of the above problems, a new superheated steam generation scheme needs to be proposed. Summary of the invention

[0006] The purpose of the embodiments of the present invention is to provide a parallel molten salt heated superheated steam generation system and a control method thereof, so as to at least solve the problems of insufficient operating efficiency and difficulty in ensuring steam effect in existing solutions.

[0007] In order to achieve the above-mentioned objectives, the first aspect of the present invention provides a parallel molten salt heated superheated steam generating system, the system comprising: an evaporator system and a superheater system connected in sequence, which are combined to process oilfield produced water into corresponding steam for steam injection; wherein the evaporator system and the superheater system both have separate molten salt supply devices, and the molten salt supply devices are used to provide a heat source for the operation of the evaporator system and the superheater system; the cold salt of the molten salt supply devices of the evaporator system and the superheater system are collected into the same cold salt recovery device; a control module is used to construct a corresponding salt supply linkage model based on real-time operating conditions, so as to generate an optimal molten salt supply device joint control scheme that meets the steam injection demand conditions based on the salt supply linkage model; an execution module is respectively arranged on the salt supply pipelines of the molten salt supply devices of the evaporator system and the superheater system, and is used to execute molten salt supply adjustment based on the optimal molten salt supply device joint control scheme.

[0008] Optionally, the evaporator system includes a plurality of heat exchangers connected in series, so that the produced water after heat exchange in the previous heat exchanger flows into the current heat exchanger to perform secondary heat exchange.

[0009] Optionally, the system further includes: a preheating system connected to the front end of the evaporator system; the preheating system is used to preheat the produced water and supply the preheated produced water to the preheating system.

[0010] Optionally, the superheater system includes: a steam-water separator connected to the output pipe of the evaporator system, and used to separate the wet saturated steam output by the evaporator system into steam and water to obtain dry steam and saturated water respectively; a superheater connected to the pipe through which the dry steam is output from the steam-water separator, and used to realize heat exchange between the dry steam and the hot molten salt in the molten salt supply device of the superheater system to convert the dry steam into superheated dry steam; a mixer, which collects the superheated dry steam and the saturated water, and is used to generate steam for steam injection based on the mixing of the superheated dry steam and the saturated water.

[0011] Optionally, the molten salt supply device of the superheater system includes: a second salt supply pipeline arranged in the opposite direction of the dry steam output direction of the steam-water separator, and the second salt supply pipeline is arranged in the same path as the dry steam delivery pipeline in the superheater; the execution module arranged on the superheater system includes: a second hot salt pump, used to pump hot salt into the second salt supply pipeline; a second three-way regulating valve arranged on the second salt supply pipeline between the superheater and the second hot salt pump, used to control the hot salt flow rate flowing into the superheater corresponding to the second salt supply pipeline; the molten salt supply device of the superheater system also includes: a second hot salt return pipeline arranged on the third end of the second three-way regulating valve, used to return excess hot salt in the total hot salt flow rate output by the second hot salt pump that does not flow to the superheater system to the hot salt storage system.

[0012] Optionally, the molten salt supply device of the evaporator system includes: a first salt supply pipeline arranged in the direction from the last heat exchanger to the first heat exchanger of the evaporator system; the execution module arranged on the evaporator system includes: a first hot salt pump, used to pump hot salt into the first salt supply pipeline; a first three-way regulating valve arranged on the first salt supply pipeline between the last heat exchanger and the first hot salt pump, used to control the hot salt flow rate flowing into the corresponding first salt supply pipeline of the evaporator system; the molten salt supply device of the evaporator system also includes: a first hot salt return pipeline arranged on the third end of the first three-way regulating valve, used to return excess hot salt in the total hot salt flow rate output by the first hot salt pump that does not flow to the evaporator system to the hot salt storage system.

[0013] Optionally, the control module is configured to: collect demand information of steam for steam injection, and use the demand information of steam for steam injection as a basic constraint; construct a corresponding optimization model based on the basic constraints and an artificial immune algorithm, wherein the optimization objective of the optimization model is to minimize hot salt consumption; perform iterative solution on the optimization model until an iteration termination condition is triggered, and output an optimal control scheme for the molten salt supply device of the evaporator system and the superheater system as an optimal molten salt supply device joint control scheme.

[0014] Optionally, the corresponding optimization model is constructed based on the basic constraints and the artificial immune algorithm, including: taking the first hot salt pump, the second hot salt pump, the valve opening of the first three-way regulating valve on the evaporator system side, and the valve opening of the second three-way regulating valve on the superheater system side as antibody structures; constructing a corresponding fitness function to evaluate the fitness of each antibody; specifying a corresponding mutation frequency, and constructing a corresponding optimization model based on the antibody structure, fitness function and mutation frequency.

[0015] Optionally, the fitness function is expressed as:

[0016] in, is the fitness value; Total hot salt consumption; , represents the error between the steam quality of steam injection and the target steam quality; and are the target wet steam dryness and the actual wet steam dryness respectively; and are the target superheated steam temperature and the actual superheated steam temperature respectively; and are the preset weights for total hot salt consumption and steam quality error respectively.

[0017] Optionally, the iterative solution of the optimization model is performed until an iteration termination condition is triggered, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme, including: performing model initialization, randomly generating multiple antibodies within a design range of a preset operating frequency of the molten salt supply device and a design range of the opening and closing degree of each valve, as an initial antibody population; calculating the fitness of each antibody in the initial antibody population, and selecting antibodies with a fitness greater than a preset fitness threshold to perform mutation in the optimization direction to obtain mutated antibodies; selecting antibodies with a fitness greater than a preset fitness threshold from the mutated antibodies to perform mutation in the optimization direction again, so as to repeat multiple mutations until the number of iterations is reached, or the fitness function reaches a convergence condition, the iteration is stopped, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme.

[0018] Optionally, the rule for determining the optimization direction is: introduce PID control logic, determine the control point of PID, and determine the optimization direction based on the control point of PID; wherein, the control point of PID of the valve opening on the evaporator system side of the first hot salt pump and the first three-way regulating valve is confirmed based on the dryness of the wet saturated steam; the control point of PID of the valve opening on the superheater system side of the second hot salt pump and the second three-way regulating valve is confirmed based on the temperature of the superheated steam.

[0019] Optionally, the PID control action point of the valve opening of the first hot salt pump and the first three-way regulating valve evaporator system side is based on the dryness of the wet saturated steam and the confirmation rule is:

[0020] in, It is the combined control output of the valve opening of the first hot salt pump and the first three-way regulating valve on the evaporator system side; is the dryness error of wet saturated steam; , and They are proportional gain, integral gain and differential gain respectively.

[0021] Optionally, the PID control action point of the valve opening of the second hot salt pump and the second three-way regulating valve on the superheater system side is based on the confirmation rule of the superheated steam temperature execution confirmation:

[0022] in, It is the combined control output of the valve opening of the second hot salt pump and the second three-way regulating valve on the superheater system side; Temperature error of superheated steam for steam injection; , and They are proportional gain, integral gain and differential gain respectively.

[0023] Optionally, PID control logic is introduced to determine the control action point of PID, and the optimization direction is determined based on the control action point of PID, including: dynamically correcting the variables of the antibody solution through PID control logic to optimize the steam quality; calculating the fitness value using the variables adjusted by PID, and determining the optimal control action point based on the fitness evaluation result; and performing antibody mutation based on the optimal control point as the corresponding optimization direction.

[0024] Optionally, the control scheme of the molten salt supply device for the evaporator system and the superheater system with the optimal output, as an optimal molten salt supply device joint control scheme, includes: a joint control output of the valve opening of the first hot salt pump and the first three-way regulating valve on the evaporator system side and a joint control output of the valve opening of the second hot salt pump and the second three-way regulating valve on the superheater system side under the PID control logic of the final iterative round, performing control strategy decoupling of each joint control output, and respectively obtaining the target power of the first hot salt pump, the target valve opening of the first three-way regulating valve on the evaporator system side, the target power of the second hot salt pump and the target valve opening of the second three-way regulating valve on the superheater system side, so as to generate corresponding control schemes as the optimal molten salt supply device joint control scheme.

[0025] The second aspect of the present invention provides a control method for a parallel molten salt heated superheated steam generating system, characterized in that the method is applied to the above-mentioned parallel molten salt heated superheated steam generating system, and the method includes: collecting demand information for steam injection, using the demand information for steam injection as a basic constraint; constructing a corresponding optimization model based on the basic constraint and an artificial immune algorithm, and the optimization target of the optimization model is the minimum hot salt consumption; performing iterative solution on the optimization model until the iteration termination condition is triggered, and outputting the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system as the optimal molten salt supply device joint control scheme.

[0026] Optionally, the corresponding optimization model is constructed based on the basic constraints and the artificial immune algorithm, including: taking the first hot salt pump, the second hot salt pump, the valve opening of the first three-way regulating valve on the evaporator system side, and the valve opening of the second three-way regulating valve on the superheater system side as antibody structures; constructing a corresponding fitness function to evaluate the fitness of each antibody; specifying a corresponding mutation frequency, and constructing a corresponding optimization model based on the antibody structure, fitness function and mutation frequency.

[0027] Optionally, the iterative solution of the optimization model is performed until an iteration termination condition is triggered, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme, including: performing model initialization, randomly generating multiple antibodies within a design range of a preset operating frequency of the molten salt supply device and a design range of the opening and closing degree of each valve, as an initial antibody population; calculating the fitness of each antibody in the initial antibody population, and selecting antibodies with a fitness greater than a preset fitness threshold to perform mutation in the optimization direction to obtain mutated antibodies; selecting antibodies with a fitness greater than a preset fitness threshold from the mutated antibodies to perform mutation in the optimization direction again, so as to repeat multiple mutations until the number of iterations is reached, or the fitness function reaches a convergence condition, the iteration is stopped, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme.

[0028] Optionally, the rule for determining the optimization direction is: introduce PID control logic, determine the control point of PID, and determine the optimization direction based on the control point of PID; wherein, the control point of PID of the valve opening on the evaporator system side of the first hot salt pump and the first three-way regulating valve is confirmed based on the dryness of the wet saturated steam; the control point of PID of the valve opening on the superheater system side of the second hot salt pump and the second three-way regulating valve is confirmed based on the temperature of the superheated steam.

[0029] Optionally, the control scheme of the molten salt supply device for the evaporator system and the superheater system with the optimal output, as an optimal molten salt supply device joint control scheme, includes: a joint control output of the valve opening of the first hot salt pump and the first three-way regulating valve on the evaporator system side and a joint control output of the valve opening of the second hot salt pump and the second three-way regulating valve on the superheater system side under the PID control logic of the final iterative round, performing control strategy decoupling of each joint control output, and respectively obtaining the target power of the first hot salt pump, the target valve opening of the first three-way regulating valve on the evaporator system side, the target power of the second hot salt pump and the target valve opening of the second three-way regulating valve on the superheater system side, so as to generate corresponding control schemes as the optimal molten salt supply device joint control scheme.

[0030] On the other hand, the present invention provides a computer-readable storage medium having instructions stored thereon, which, when executed on a computer, enables the computer to execute the above-mentioned parallel molten salt heated superheated steam generation system control method.

[0031] Through the above technical scheme, the scheme of the present invention realizes the coordinated optimization of the molten salt supply process of the evaporator system and the superheater system by introducing a salt supply linkage model and a real-time control mechanism. By equipping the two systems with independent molten salt supply devices respectively and integrating their cold salt recovery into the same cold salt recovery device, the centralization of cold salt management and the reheating efficiency are enhanced, and the overall operation stability and energy efficiency of the system are significantly improved. The control module can dynamically generate a salt supply linkage scheme according to the real-time operating conditions, and accurately adjust the molten salt supply in the salt supply pipeline through the execution module to ensure that the steam quality (wet steam dryness and superheated steam temperature) meets the steam injection requirements. This scheme not only reduces the consumption of molten salt, but also solves the problems of uncoordinated salt supply ratio and steam quality fluctuation in the prior art, greatly improves the dynamic response capability of the steam injection system, and provides a more efficient solution for heavy oil production.

[0032] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings: Figure 1 It is a system structure diagram of a parallel molten salt heating superheated steam generating system provided by one embodiment of the present invention; Figure 2 It is a specific structural schematic diagram of a parallel molten salt heating superheated steam generating system provided by one embodiment of the present invention; Figure 3 It is a flow chart of the steps of a control method for a parallel molten salt heated superheated steam generation system provided by one embodiment of the present invention.

[0034] Description of Reference Numerals 1- water supply pipeline; 2- evaporator system; 3.- wet steam pipeline; 4- dryness online monitoring device; 5- first signal line; 6- first control system; 7- superheater system; 8- superheated steam pipeline; 9- temperature online monitoring device; 10- second signal line; 11- 2nd-2 hot salt pipeline; 12- second control system; 13- second hot salt pump; 14- 2nd-1st hot salt pipeline; 15- second three-way regulating valve; 16- second return salt pipeline; 17- first hot salt pump; 18- 1st-1st hot salt pipeline; 19- first three-way regulating valve; 20- first return salt pipeline; 21- 1st-2nd hot salt pipeline; 22- second cold salt pipeline; 23- first cold salt pipeline. DETAILED DESCRIPTION

[0035] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0036] Figure 1 1 is a system structure diagram of a parallel molten salt heating superheated steam generation system provided by an embodiment of the present invention. Figure 1 As shown, an embodiment of the present invention provides a parallel molten salt heated superheated steam generating system, the system comprising: an evaporator system 2 and a superheater system 7 connected in sequence, which are combined to process oilfield produced water into corresponding steam for steam injection; wherein the evaporator system 2 and the superheater system 7 each have a separate molten salt supply device, and the molten salt supply device is used to provide a heat source for the operation of the evaporator system 2 and the superheater system 7; the cold salt of the molten salt supply devices of the evaporator system 2 and the superheater system 7 is collected into the same cold salt recovery device; a control module is used to construct a corresponding salt supply linkage model based on real-time operating conditions, so as to generate an optimal molten salt supply device joint control scheme that meets the steam injection demand conditions based on the salt supply linkage model; an execution module is respectively arranged on the salt supply pipelines of the molten salt supply devices of the evaporator system 2 and the superheater system 7, and is used to execute molten salt supply quantity adjustment based on the optimal molten salt supply device joint control scheme. Preferably, the evaporator system 2 includes a plurality of heat exchangers connected in series, so that the produced water after heat exchange in the previous heat exchanger flows into the current heat exchanger to perform secondary heat exchange.

[0037] In an embodiment of the present invention, the produced water first enters the first-stage heat exchanger and performs preliminary heat exchange with the hot salt to increase the water temperature; then it flows into the next-stage heat exchanger and continues to perform deep heat exchange with the hot salt, so that the water temperature is gradually increased until it reaches the design requirements. Through this multi-stage series heat exchange method, the utilization efficiency of the hot salt can be effectively improved, and the energy loss caused by the large temperature difference in the single-stage heat exchange can be avoided. Multi-stage heat exchange can also reduce the risk of local scaling, because the gradual temperature increase design reduces the scaling probability of high-silicon water under high temperature conditions, thereby extending the service life of the heat exchanger. In addition, the design optimizes the series connection process of the heat exchanger so that the evaporator system 2 can flexibly adapt to the changes in produced water temperature and flow rate under different working conditions. The first-stage heat exchanger is mainly responsible for heating the produced water to a lower range of saturation temperature, while the subsequent heat exchanger completes the wet steam generation process according to the design load. This can ensure the operating stability of the entire system and provide high-quality wet steam under low or high load conditions.

[0038] Furthermore, the system also includes: a preheating system connected to the front end of the evaporator system 2; the preheating system is used to preheat the produced water and supply the preheated produced water to the preheating system.

[0039] In the embodiment of the present invention, the main function of the preheating system is to preheat the produced water using a low-grade heat source, raise the water temperature from the ambient temperature to an initial heating level, and then transport the preheated produced water to the evaporator system 2 for further heating and steam generation. The preheating system can choose to use waste heat, waste heat recovery system or low-temperature hot salt as a heat source, fully utilize the remaining thermal energy resources in the system, and effectively reduce the consumption of high-grade hot salt.

[0040] By adding a preheating link before the evaporator system 2, not only the thermal efficiency of the overall system is improved, but also the heat load of the heat exchanger in the evaporator system 2 is reduced. Specifically, the preheating system raises the produced water temperature to a lower limit close to the saturation temperature, thereby reducing the heat required for heat exchange in the evaporator. This design can not only shorten the heating time of the evaporator system 2, but also reduce the delivery volume of hot salt and the working intensity of the pump, greatly improving the operating economy of the system.

[0041] Preferably, the superheater system 7 includes: a steam-water separator connected to the output pipe of the evaporator system 2, and used to perform steam-water separation on the wet saturated steam output by the evaporator system 2 to obtain dry steam and saturated water respectively; a superheater connected to the pipe for outputting dry steam from the steam-water separator, and used to realize heat exchange between the dry steam and the hot molten salt in the molten salt supply device of the superheater system 7 to convert the dry steam into superheated dry steam; a mixer, which collects the superheated dry steam and the saturated water, and is used to generate steam for steam injection based on the mixing of the superheated dry steam and the saturated water.

[0042] In an embodiment of the present invention, the working process of the superheater system 7 is as follows: First, the wet saturated steam is output by the evaporator system 2 and enters the steam-water separator, and the steam-water separator separates the wet steam into dry steam and saturated water through efficient separation technology. The dry steam is transported to the superheater through a connecting pipe, and heat is exchanged with the hot molten salt from the molten salt supply device of the superheater system 7, and it is further heated to become superheated dry steam. Subsequently, the superheated dry steam and the saturated water separated by the steam-water separator are mixed in a mixer according to a set ratio to generate steam that meets the steam injection requirements. This design fully considers the different requirements for the dryness and temperature of wet saturated steam, and adjusts the steam quality to an appropriate range through the separation treatment of the steam-water separator and the precise heating of the superheater. At the same time, the addition of the mixer further enhances flexibility, enabling the system to adapt to different steam injection requirements by adjusting the mixing ratio without changing the front-end production process.

[0043] Based on the scheme of the present invention, wet saturated steam is separated into dry steam and saturated water by a steam-water separator, eliminating the influence of droplets in wet steam and ensuring the stability and efficiency of the subsequent superheating process. The superheater uses high-temperature molten salt to heat dry steam, which can heat the steam to a precise superheat temperature range to meet the needs of different steam injection processes. The setting of the mixer enables the system to adjust the temperature and dryness of the final steam according to the steam injection requirements by mixing superheated dry steam and saturated water, and adapt to the requirements of different heavy oil blocks. The recycling of saturated water reduces energy waste, while the mixing process avoids the waste of superheated steam and realizes efficient operation of the system. The application of the steam-water separator reduces the corrosion and scaling of the superheater caused by droplet scouring, reduces equipment maintenance costs and prolongs service life. The multi-stage process of separation-heating-mixing optimizes the dynamic response capability of steam generation, so that the system can still maintain stable operation when the load fluctuates or the produced water conditions change.

[0044] Preferably, the molten salt supply device of the superheater system 7 includes: a second salt supply pipeline arranged in the opposite direction of the dry steam output direction of the steam-water separator, and the second salt supply pipeline is arranged in the same path as the dry steam delivery pipeline in the superheater; the execution module arranged on the superheater system 7 includes: a second hot salt pump 13, used to pump hot salt into the second salt supply pipeline; a second three-way regulating valve 15 arranged on the second salt supply pipeline between the superheater and the second hot salt pump 13, used to control the hot salt flow rate flowing into the second salt supply pipeline corresponding to the superheater; the molten salt supply device of the superheater system 7 also includes: a second hot salt reflux pipeline arranged on the third end of the second three-way regulating valve 15, used to reflux the excess hot salt in the total hot salt flow rate output by the second hot salt pump 13 that does not flow to the superheater system 7 to the hot salt storage system.

[0045] In an embodiment of the present invention, the molten salt supply device of the superheater system 7 is composed of modules such as a second salt supply pipeline, a second hot salt pump 13, a second three-way regulating valve 15, and a second hot salt reflux pipeline, forming a closed-loop molten salt flow control system. The second salt supply pipeline is arranged in the same path as the dry steam delivery pipeline in the superheater, and its design fully considers the maximization of the heat exchange efficiency between hot salt and dry steam. Driven by the second hot salt pump 13, the high-temperature molten salt is transported to the superheater through the second salt supply pipeline, heat exchanged with the dry steam, and further heated to a preset superheat temperature. At the same time, the second three-way regulating valve 15 is installed between the second hot salt pump 13 and the superheater to adjust the hot salt flow to the superheater, ensuring that the system can stably output high-quality superheated dry steam under different load conditions.

[0046] Furthermore, in order to avoid molten salt waste and further optimize energy efficiency, the third end of the second three-way regulating valve 15 is connected to the second hot salt return pipe. Through this return mechanism, the excess hot salt not consumed by the superheater is quickly recovered to the hot salt storage system and recycled again. This design not only reduces energy consumption, but also can dynamically optimize the hot salt distribution ratio through the return adjustment mechanism, thereby reducing the operating pressure of the superheater system 7.

[0047] Preferably, the molten salt supply device of the evaporator system 2 includes: a first salt supply pipeline arranged in the direction from the last heat exchanger of the evaporator system 2 to the first heat exchanger; the execution module arranged on the evaporator system 2 includes: a first hot salt pump 17, used to pump hot salt into the first salt supply pipeline; a first three-way regulating valve 19 arranged on the first salt supply pipeline between the last heat exchanger and the first hot salt pump 17, used to control the hot salt flow rate flowing into the first salt supply pipeline corresponding to the evaporator system 2; the molten salt supply device of the evaporator system 2 also includes: a first hot salt reflux pipeline arranged on the third end of the first three-way regulating valve 19, used to reflux excess hot salt in the total hot salt flow rate output by the first hot salt pump 17 that does not flow to the evaporator system 2 to the hot salt storage system.

[0048] In an embodiment of the present invention, the first salt supply pipeline is arranged along the heat exchangers in the evaporator system 2, extending from the last heat exchanger to the first heat exchanger. This countercurrent arrangement design allows the hot salt to first contact the heat exchanger area with a higher temperature, and then flow through the heat exchangers with lower temperatures in sequence, thereby maximizing the heat transfer efficiency of the hot salt. In this way, the thermal energy of the hot salt is gradually released, so that each stage of the heat exchanger in the evaporator system 2 can absorb heat in the most efficient way. The first hot salt pump 17 is responsible for pumping the hot salt from the hot salt storage system into the first salt supply pipeline to provide the required heat for the evaporator system 2. The operating frequency of the hot salt pump can be dynamically adjusted according to the system load to meet the hot salt demand under different working conditions, thereby achieving energy saving and efficient operation.

[0049] Furthermore, the first three-way regulating valve 19 disposed between the last heat exchanger and the first hot salt pump 17 has a flow regulating function. By adjusting the valve opening, the hot salt flow entering the evaporator system 2 is controlled to ensure that the hot salt supply matches the current heat exchange demand of the evaporator system 2. The three-way valve design makes the hot salt supply highly flexible and can quickly respond to the operating changes of the evaporator system 2. The excess hot salt that does not flow to the evaporator system 2 is transported to the first hot salt return pipe through the third end of the first three-way regulating valve 19 and directly returned to the hot salt storage system. This design can quickly recover and reuse excess hot salt, effectively reducing the waste of hot salt, while reducing the burden on the hot salt pump and optimizing the energy efficiency of the entire heating system.

[0050] Preferably, the control module is configured to: collect demand information of steam for steam injection, and use the demand information of steam for steam injection as a basic constraint; construct a corresponding optimization model based on the basic constraint and artificial immune algorithm, and the optimization target of the optimization model is the minimum hot salt consumption; perform iterative solution on the optimization model until the iteration termination condition is triggered, and output the optimal control scheme of the molten salt supply device of the evaporator system 2 and the superheater system 7 as the optimal molten salt supply device joint control scheme.

[0051] In the embodiment of the present invention, the control module first collects the demand information of steam for steam injection, including target steam parameters (pressure, temperature, dryness) and real-time operating data (produced water flow, inlet water temperature, etc.). This information serves as the basic constraint of the optimization process and provides clear goals and constraints for the control scheme of the molten salt supply device.

[0052] Based on the above basic constraints, the control module uses an artificial immune algorithm to construct a corresponding optimization model. The artificial immune algorithm is inspired by the biological immune system and has efficient global optimization capabilities and adaptability through mechanisms such as selection, cloning, mutation, and memory. The goal of the optimization model is set to achieve the minimum hot salt consumption, thereby maximizing system energy efficiency and reducing operating costs while meeting steam quality requirements. Through the iterative solution of the artificial immune algorithm, the model can dynamically adjust the control parameters of the evaporator and superheater molten salt supply device, including the hot salt pump frequency and the three-way valve opening.

[0053] During the iteration process, the control module evaluates the optimal solution in real time according to the actual working conditions, and ensures the convergence and computational efficiency of the optimization process by setting reasonable iteration termination conditions (error threshold or maximum number of iterations). When the iteration termination conditions are triggered, the control module outputs the optimal control scheme, which is the joint control strategy of the molten salt supply device of the evaporator and superheater system 7.

[0054] Furthermore, the corresponding optimization model is constructed based on the basic constraints and the artificial immune algorithm, including: taking the valve opening of the first hot salt pump 17, the second hot salt pump 13, the first three-way regulating valve 19 on the evaporator system 2 side and the valve opening of the second three-way regulating valve 15 on the superheater system 7 side as antibody structures; constructing a corresponding fitness function for evaluating the fitness of each antibody; specifying a corresponding mutation frequency, and constructing a corresponding optimization model based on the antibody structure, fitness function and mutation frequency.

[0055] In an embodiment of the present invention, the key control variables of the system (including the frequency of the first hot salt pump 17, the frequency of the second hot salt pump 13, the valve opening of the first three-way regulating valve 19 on the evaporator side, and the valve opening of the second three-way regulating valve 15 on the superheater side) are used as components of the antibody structure. These variables directly affect the flow distribution of the molten salt supply and the thermal efficiency of the system, and are the core parameters for achieving precise control. In the model, the fitness function is a key indicator for evaluating the quality of each antibody. The fitness function comprehensively considers the steam quality error (such as the deviation of the dryness and temperature from the target value) and the hot salt consumption. In order to achieve dynamic optimization of the model, a reasonable mutation frequency is specified, and new antibodies are generated through the mutation mechanism of the artificial immune algorithm. The mutation mechanism introduces small disturbances to simulate the adjustment of the hot salt pump frequency or valve opening, thereby enhancing the diversity of the antibody population and avoiding falling into a local optimal solution. At the same time, antibodies with higher fitness will be cloned first to speed up the global optimization process. Finally, through the screening, cloning and mutation iteration of antibodies, the model can output a set of control parameters with the highest fitness to form an optimal molten salt supply joint control scheme.

[0056] Preferably, the fitness function is expressed as:

[0057] in, is the fitness value; Total hot salt consumption; , represents the error between the steam quality of steam injection and the target steam quality; and are the target wet steam dryness and the actual wet steam dryness respectively; and are the target superheated steam temperature and the actual superheated steam temperature respectively; and are the preset weights for total hot salt consumption and steam quality error respectively.

[0058] In the embodiment of the present invention, the fitness function mainly consists of two parts: total hot salt consumption and steam quality error. The total hot salt consumption reflects the energy usage of the system operation and is an important indicator for measuring the energy efficiency of the system. By reducing the use of hot salt, not only can the operating cost be reduced, but also the energy utilization efficiency can be improved, thereby achieving the goal of energy saving and emission reduction.

[0059] Steam quality error is another key component of the fitness function, which is used to quantify the deviation between the actual parameters of steam injection and the target parameters. Specifically, the steam quality error includes the deviation of wet steam dryness and superheated steam temperature. The size of dryness deviation and temperature deviation directly affects the use effect of steam, especially in heavy oil production, where the requirements for steam quality are very strict. Therefore, by strictly controlling the steam quality error, the dryness and temperature of the output steam can be guaranteed to be stable and meet the steam injection needs of different oil fields.

[0060] In order to achieve a balance between the total hot salt consumption and the steam quality error, the fitness function introduces a weight parameter to adjust the influence of the two parts. This design can flexibly adjust the optimization target according to actual needs. For example, when energy saving is prioritized, the weight of hot salt consumption can be increased, while in scenarios with high steam quality requirements, the weight of steam quality error can be increased.

[0061] Preferably, the iterative solution of the optimization model is performed until the iteration termination condition is triggered, and the optimal control scheme of the molten salt supply device of the evaporator system 2 and the superheater system 7 is output as the optimal molten salt supply device joint control scheme, including: performing model initialization, randomly generating multiple antibodies within the design range of a preset operating frequency of the molten salt supply device and the opening and closing degree of each valve as an initial antibody population; calculating the fitness of each antibody in the initial antibody population respectively, and selecting antibodies with a fitness greater than a preset fitness threshold to perform mutation in the optimization direction to obtain mutated antibodies; selecting antibodies with a fitness greater than a preset fitness threshold from the mutated antibodies to perform mutation in the optimization direction again, so as to repeat multiple mutations until the number of iterations is reached, or the fitness function reaches a convergence condition, the iteration is stopped, and the optimal control scheme of the molten salt supply device of the evaporator system 2 and the superheater system 7 is output as the optimal molten salt supply device joint control scheme.

[0062] Preferably, the rule for determining the optimization direction is: introduce PID control logic, determine the control point of PID, and determine the optimization direction based on the control point of PID; wherein, the PID control point of the valve opening of the first hot salt pump 17 and the first three-way regulating valve 19 on the evaporator system 2 side is confirmed based on the dryness of the wet saturated steam; the PID control point of the valve opening of the second hot salt pump 13 and the second three-way regulating valve 15 on the superheater system 7 side is confirmed based on the temperature of the superheated steam.

[0063] In the embodiment of the present invention, the scheme of the present invention combines the steam quality control requirements and the minimum hot salt consumption target in the initialization stage, optimization stage and convergence termination stage, effectively improving the operating efficiency of the steam injection system and the stability of the steam quality. Specifically, the following steps are included: 1) Model initialization: In the initialization stage, multiple antibodies are randomly generated within the preset operating frequency range of the molten salt supply device and the design range of the valve opening and closing degree. These antibodies represent possible control parameter combinations, including the frequency of the first hot salt pump 17 and the second hot salt pump 13, and the opening of the first three-way regulating valve 19 and the second three-way regulating valve 15. These antibodies constitute the initial antibody population as the initial solution space for optimization. The fitness value of each antibody is calculated by the fitness function, which integrates the system's hot salt consumption and steam quality error (including the deviation of wet steam dryness and superheated steam temperature). The higher the fitness value, the closer the corresponding antibody is to the optimization target.

[0064] 2) Mutation optimization stage: In the optimization phase, mutation operations are performed on antibodies in the initial population whose fitness is greater than the preset threshold. The purpose of mutation is to generate a new solution space by partially adjusting the antibody structure to explore a better combination of control parameters. The mutation operation is based on the following rules: PID control logic is introduced to dynamically adjust the optimization direction. The control action point of PID is confirmed by real-time steam parameter feedback: the optimization direction of the first hot salt pump 17 and the first three-way regulating valve 19 is determined by the wet steam dryness control point. By real-time monitoring of wet steam dryness, the PID control logic adjusts the frequency of the first hot salt pump 17 and the opening of the first three-way regulating valve 19 to stabilize the wet steam dryness within the target value range. The optimization direction of the second hot salt pump 13 and the second three-way regulating valve 15 is determined by the superheated steam temperature control point. By monitoring the superheated steam temperature, the PID control logic dynamically adjusts the frequency of the second hot salt pump 13 and the opening of the second three-way regulating valve 15 to ensure that the superheated steam temperature meets the steam injection demand.

[0065] Mutation rules: Antibodies with higher fitness are preferentially selected for mutation. In each round of mutation, small perturbations (such as fine-tuning of the upper and lower limits of the pump frequency or changes in the valve opening) are introduced to generate new antibodies.

[0066] 3) Iterative solution: After the variant antibodies are generated, their fitness values ​​are calculated again, and antibodies with fitness values ​​greater than the threshold are included in the next round of optimization iterations. This process is repeated until one of the following conditions is met: Reaching the preset number of iterations indicates that the algorithm's optimization exploration has been fully launched.

[0067] The fitness function converges, that is, the optimal control parameter combination of the system has been determined.

[0068] When the iteration stops, the antibody with the highest fitness is output as the final control scheme, forming the optimal molten salt supply device joint control scheme for the evaporator system 2 and the superheater system 7.

[0069] Based on the scheme of the present invention, through the iterative optimization of the artificial immune algorithm and the introduction of the PID control logic, the system can realize real-time joint control optimization under dynamic conditions. The PID control logic provides a dynamic adjustment basis for the optimization direction, so that the optimization scheme always takes the balance of steam quality and hot salt consumption as the goal. The PID control point design based on the wet steam dryness and superheated steam temperature ensures that the steam quality meets the steam injection demand. During the optimization process, the real-time adjustment of dryness and temperature makes the steam output more stable and adapts to the steam injection demand under different oil field conditions. With the minimum hot salt consumption as the optimization target, the molten salt supply is dynamically adjusted to reduce unnecessary energy waste, improve the utilization efficiency of molten salt, and thus reduce the system operation cost. By introducing the variation mechanism of the artificial immune algorithm, the system can explore a broader solution space and avoid falling into the local optimal solution. At the same time, the algorithm can flexibly adapt to load fluctuations and operating conditions, enhancing the adaptability and robustness of the system. Without manual intervention, the whole process from model initialization to the output of the final optimization scheme is automatically completed, which simplifies the operation process and improves the intelligence level of the control system. The optimized molten salt supply device joint control solution significantly reduces the hot salt consumption and equipment operating load, reducing operation and maintenance costs. At the same time, reducing energy consumption helps reduce carbon emissions, which meets the needs of green and low-carbon development.

[0070] Preferably, the PID control action point of the valve opening of the first hot salt pump 17 and the first three-way regulating valve 19 on the evaporator system 2 side is based on the confirmation rule of the dryness of the wet saturated steam execution confirmation:

[0071] in, It is the combined control output of the valve opening of the first hot salt pump 17 and the first three-way regulating valve 19 on the evaporator system 2 side; is the dryness error of wet saturated steam; , and They are proportional gain, integral gain and differential gain respectively.

[0072] In an embodiment of the present invention, the PID control logic monitors the dryness of wet saturated steam in real time, takes the deviation between the actual dryness and the target dryness as the control input, and calculates the joint control output based on the proportional, integral and differential gains. The control output directly acts on the frequency adjustment of the first hot salt pump 17 and the opening adjustment of the first three-way regulating valve 19, thereby dynamically adjusting the hot salt flow entering the evaporator system 2 to achieve precise control of the steam dryness. The proportional gain is mainly used to respond to the real-time dryness error, provide rapid adjustment force, and ensure that compensatory measures are taken quickly when the dryness deviates from the target value. The integral gain corrects the long-term deviation of the system by accumulating historical errors to avoid steady-state errors in the system during operation; the differential gain improves the dynamic response capability of the system by predicting the changing trend of the dryness error and reduces the adjustment lag caused by too fast dryness changes.

[0073] Preferably, the PID control action point of the valve opening of the second hot salt pump 13 and the second three-way regulating valve 15 on the superheater system 7 side is based on the confirmation rule of the superheated steam temperature execution confirmation:

[0074] in, It is the combined control output of the valve opening of the second hot salt pump 13 and the second three-way regulating valve 15 on the superheater system 7 side; Temperature error of superheated steam for steam injection; , and They are proportional gain, integral gain and differential gain respectively.

[0075] In an embodiment of the present invention, the control logic monitors the actual temperature of the superheated steam, compares it with the target temperature, and obtains the temperature error as input. The PID controller generates a joint control output based on the calculation rules of proportion, integration and differentiation, which is used to dynamically adjust the operating frequency of the second hot salt pump 13 and the opening of the second three-way regulating valve 15, thereby adjusting the hot salt flow entering the superheater system 7. The proportional control part responds quickly to the current temperature error and provides immediate adjustment force to ensure that compensation measures are taken quickly when the temperature deviates from the target value. The integral control part corrects the deviation of the system during long-term operation by accumulating the temperature error to avoid the accumulation of steady-state errors. The differential control part responds to possible rapid temperature fluctuations in advance by predicting the changing trend of the temperature error, thereby enhancing the dynamic adjustment capability of the system.

[0076] Preferably, PID control logic is introduced to determine the control action point of PID, and the optimization direction is determined based on the control action point of PID, including: dynamically correcting the variables of the antibody solution through the PID control logic to optimize the steam quality; calculating the fitness value using the variables adjusted by PID, and determining the optimal control action point based on the fitness evaluation result; and performing antibody variation based on the optimal control point as the corresponding optimization direction.

[0077] In the embodiment of the present invention, the PID control logic takes the deviation between the target value and the actual value as input according to the real-time feedback of the steam quality parameters (wet steam dryness and superheated steam temperature), and dynamically corrects the variables of the antibody solution through proportional, integral and differential calculations. These variables usually include the frequency of the hot salt pump and the opening of the three-way valve, which are the core factors affecting the molten salt flow rate and steam quality. After being corrected by the PID logic, the variables can more accurately meet the steam quality requirements and form an optimized preliminary control plan.

[0078] On this basis, the fitness value is calculated using the corrected variables. The fitness value evaluation not only reflects the hot salt consumption of the current control scheme, but also measures the error in steam quality (deviation of dryness and temperature). The fitness evaluation results are used to further screen the optimal control action points, which represent the best adjustment strategy for the system under the current operating conditions. After determining the optimal control action point, the antibody mutation operation is further performed based on the action point. Mutation generates new antibody solutions by applying small disturbances to the variables, thereby expanding the solution space and exploring better control schemes. The mutated antibody solution has a clear direction and is more in line with the goal of steam quality optimization.

[0079] Preferably, the control scheme of the molten salt supply device of the evaporator system 2 and the superheater system 7 with the optimal output, as the optimal molten salt supply device joint control scheme, includes: the joint control output of the valve opening of the first hot salt pump 17 and the first three-way regulating valve 19 on the evaporator system 2 side and the joint control output of the valve opening of the second hot salt pump 13 and the second three-way regulating valve 15 on the superheater system 7 side under the PID control logic of the final iterative round, and the control strategy decoupling of each joint control output is performed to obtain the target power of the first hot salt pump 17, the target valve opening of the first three-way regulating valve 19 on the evaporator system 2 side, the target power of the second hot salt pump 13 and the target valve opening of the second three-way regulating valve 15 on the superheater system 7 side, respectively, to generate corresponding control schemes as the optimal molten salt supply device joint control scheme.

[0080] In an embodiment of the present invention, the scheme of the present invention utilizes PID control logic to jointly optimize the key control parameters of the evaporator system 2 and the superheater system 7, and decouples based on the control output in the final iteration round to generate specific target values ​​for each control device, including the target power of the first hot salt pump 17, the target valve opening of the first three-way regulating valve 19 on the evaporator system 2 side, the target power of the second hot salt pump 13, and the target valve opening of the second three-way regulating valve 15 on the superheater system 7 side.

[0081] By decoupling the control strategy, the control target of each device can be optimized independently, thus eliminating the interference problem between devices and ensuring that each device can work together in the most efficient way during operation. The control of the first hot salt pump 17 and the first three-way regulating valve 19 is mainly based on the wet steam dryness target of the evaporator system 2, and the stability of the wet steam dryness is maintained by dynamically adjusting the hot salt flow and distribution ratio; the second hot salt pump 13 and the second three-way regulating valve 15 are based on the superheated steam temperature target of the superheater system 7, and the temperature of the superheated steam is ensured to meet the steam injection requirements by accurately adjusting the hot salt supply.

[0082] In a possible implementation, Figure 2 , a specific structural diagram of a parallel molten salt heating superheated steam generating system is provided. Specifically, it includes: a water pipeline 1, an evaporator system 2, a wet steam pipeline 3, a dryness online monitoring device 4, a first signal line 5, a first control system 6, a superheater system 7, a superheated steam pipeline 8, a temperature online monitoring device 9, a second signal line 10, a 2nd-2 hot salt pipeline 11, a second control system 12, a second hot salt pump 13, a 2nd-1 hot salt pipeline 14, a second three-way regulating valve 15, a second return salt pipeline 16, a first hot salt pump 17, a 1st-1 hot salt pipeline 18, a first three-way regulating valve 19, a first return salt pipeline 20, a 1st-1 hot salt pipeline 21, a second cold salt pipeline 22, a first cold salt pipeline 23, etc. The control module includes a first control system 6 and a second control system 12. In combination with the embodiment, the working principles and processes of each part of the system are as follows.

[0083] 1. The main equipment of the invention is composed of an evaporator system 2, a superheater system 7, a first hot salt pump 17, a second hot salt pump 13, a first three-way regulating valve 19, a second three-way regulating valve 15, etc.

[0084] 2. The produced water from the oil field is connected to the steam generator system 2 through the water supply pipeline 1; the silicon content of the produced water from the oil field can be less than 250 mg / L, and the water supply temperature can be 40-70°C; the steam generator system 2 can be composed of heat exchangers such as a preheater, a heater, and an evaporator.

[0085] 3. The produced water from the oil field exchanges heat with hot salt through the steam generator system 2 to generate wet saturated steam; in order to reduce the scaling rate of each heat exchange surface in the steam generator system 2 under the water quality condition of high silicon content in the produced water from the oil field, the dryness of the wet saturated steam can be controlled below 75%.

[0086] 4. The wet saturated steam produced by the steam generator system 2 is connected to the superheater system 7 through the wet steam pipeline 3, and then connected to the steam injection wellhead through the hot steam pipeline 8; the wet steam pressure can be 8MPa, the temperature is 295℃, and the dryness is 75%; the superheated steam temperature can be 310℃; the material of the wet steam pipeline 3 and the superheated steam pipeline 8 can be 20G carbon steel.

[0087] 5. Install a steam dryness online monitoring device 4 on the wet steam pipeline 3 at the outlet of the evaporator system 2.

[0088] 6. Install a steam temperature online monitoring device 9 on the superheated steam pipe 8 at the outlet of the superheater system 7.

[0089] 7. A portion of the hot salt in the system is pressurized by the first hot salt pump 17, connected to the first three-way regulating valve 19 through the 1-1 hot salt pipeline 18, and then connected to the evaporator system 2 through the 1-2 hot salt pipeline 21. The hot salt is converted into cold salt after heat exchange in the evaporator system 2 and connected to the first cold salt pipeline 23; the molten salt can be binary salt, the hot salt temperature can be 560°C, the first hot salt pump 17 is a variable frequency pump, and the materials of the 1-1 hot salt pipeline 18 and the 1-2 hot salt pipeline 21 can be 347H stainless steel.

[0090] 8. The hot salt can be connected to the first salt return pipeline 20 through the first three-way regulating valve 19.

[0091] 9. The first hot salt pump 17, the first three-way regulating valve 19 and the dryness online monitoring device 4 connect the signal to the first control system 6 through the first signal line 5, and realize the automatic control of the dryness stability of the wet steam at the outlet of the evaporator system 2 by adjusting the motor frequency of the first hot salt pump 17 and the opening of the first three-way regulating valve 19; to ensure the stable flow of hot salt, the frequency conversion range of the first hot salt pump 17 is 25-50HZ, and the corresponding adjustment load is 50%-100%. At this time, the first three-way regulating valve 19 is fully open (that is, all the molten salt goes through the 1-1 hot salt pipeline 21). When the dryness value displayed by the online monitoring device 4 is higher than the set value, the first control system 6 reduces the frequency of the first hot salt pump 17 through the set PID calculation logic, so that the dryness value of the online monitoring device 4 is adjusted back to the set value; on the contrary, when the dryness value displayed by the online monitoring device 4 is lower than the set value, the first control system 6 increases the frequency of the first hot salt pump 17 through the set PID calculation logic, so that the dryness value of the online monitoring device 4 is adjusted to the set value. The evaporator system is steplessly regulated within the load range of 250%-100%. When the system load is lower than 50%, the frequency of the first hot salt pump 17 is stabilized at 25HZ. At this time, the dryness signal of the dryness online monitoring device 4 is interlocked with the opening of the first three-way regulating valve 19 through the first control system 6. When the steam dryness displayed by the online monitoring device 4 is higher than the set value, the first control system 6 adjusts the first three-way regulating valve 19 through the set PID calculation logic, and the molten salt flow rate of the first return salt pipeline 20 increases, and the molten salt flow rate of the 1-1 hot salt pipeline 21 decreases. , so that the steam dryness of the online dryness monitoring device 4 is adjusted back to the set value; on the contrary, when the steam dryness displayed by the online dryness monitoring device 4 is lower than the set value, the first control system 6 adjusts the first three-way regulating valve 19 through the set PID calculation logic, the molten salt flow rate of the first return salt pipeline 20 is reduced, and the molten salt flow rate of the 1-1 hot salt pipeline 21 is increased, so that the steam dryness of the online dryness monitoring device 4 is adjusted up to the set value, realizing stable control of the steam dryness in the system load range of 0%-50%, and finally realizing stepless regulation of the evaporator system in the load range of 20%-50%.

[0092] 10. Another part of the hot salt in the system is pressurized by the second hot salt pump 13, connected to the second three-way regulating valve 15 through the 2-1 hot salt pipeline 14, and then connected to the superheater system 7 through the 2-2 hot salt pipeline 11. The hot salt is converted into cold salt after heat exchange in the superheater system 7, and is connected to the second cold salt pipeline 22, and then mixed with the cold salt from the first cold salt pipeline 23; the temperature of the cold salt after heat exchange can be 285-300°C.

[0093] 11. The other part of the hot salt can be connected to the second salt return pipeline 16 through the second three-way regulating valve 15.

[0094] 12, the second hot salt pump 13, the second three-way regulating valve 15 and the temperature online monitoring device 9 connect the signal to the second control system 12 through the second signal line 10, and the automatic control of the superheated steam temperature at the outlet of the superheater system 7 is realized by adjusting the motor frequency of the second hot salt pump 13 and the opening of the second three-way regulating valve 15; to ensure the stable flow of hot salt, the frequency conversion range of the second hot salt pump 14 is 25-50HZ, and the corresponding adjustment load is 50%-100%. At this time, the second three-way regulating valve 15 is fully open (that is, all the molten salt goes through the 2-2 hot salt pipeline 11). If the temperature value displayed by the temperature online monitoring device 9 is higher than the set value, the second control system 12 reduces the frequency of the second hot salt pump 14 through the set PID calculation logic, so that the temperature value of the temperature online monitoring device 9 is adjusted back to the set value; on the contrary, if the temperature value displayed by the temperature online monitoring device 9 is lower than the set value, the second control system 12 increases the frequency of the second hot salt pump 14 through the set PID calculation logic, so that the temperature value of the temperature online monitoring device 9 is adjusted to the set value. Achieve stepless regulation of the superheater system 7 within a load range of 50%-100%. When the system load is lower than 50%, the frequency of the second hot salt pump 14 is stabilized at 25HZ. At this time, the temperature signal of the temperature online monitoring device 9 is interlocked with the opening of the second three-way regulating valve 15 through the second control system 12. If the steam temperature displayed by the temperature online monitoring device 9 is higher than the set value, the second control system 12 adjusts the second three-way regulating valve 15 through the set PID calculation logic, the molten salt flow rate of the second return salt pipeline 16 increases, and the molten salt flow rate of the 2-2 hot salt pipeline 11 decreases, so that the steam temperature of the temperature online monitoring device 9 is adjusted back to the set value; conversely, if the steam temperature displayed by the temperature online monitoring device 9 is lower than the set value, the second control system 12 adjusts the second three-way regulating valve 15 through the set PID calculation logic, the molten salt flow rate of the second return salt pipeline 16 decreases, and the molten salt flow rate of the 2-2 hot salt pipeline 11 increases, so that the steam temperature of the temperature online monitoring device 9 is adjusted up to the set value, so as to realize the stable control of the steam temperature in the system load range of 0%-50%, and finally realize the stepless regulation of the superheater system load range of 70%-50%.

[0095] Figure 3 1 is a flow chart of a method for controlling a parallel molten salt heating superheated steam generation system provided by an embodiment of the present invention. Figure 3 As shown, an embodiment of the present invention provides a control method for a parallel molten salt heating superheated steam generation system, the method comprising: Step S10: collecting the demand information of steam for steam injection, and taking the demand information of steam for steam injection as the basic constraint.

[0096] Step S20: constructing a corresponding optimization model based on the basic constraints and the artificial immune algorithm, wherein the optimization target of the optimization model is to minimize the hot salt consumption.

[0097] Step S30: performing iterative solution on the optimization model until the iteration termination condition is triggered, and outputting the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system as the optimal molten salt supply device joint control scheme.

[0098] Preferably, the corresponding optimization model is constructed based on the basic constraints and the artificial immune algorithm, including: taking the first hot salt pump, the second hot salt pump, the valve opening of the first three-way regulating valve on the evaporator system side and the valve opening of the second three-way regulating valve on the superheater system side as antibody structures; constructing a corresponding fitness function to evaluate the fitness of each antibody; specifying a corresponding mutation frequency, and constructing a corresponding optimization model based on the antibody structure, fitness function and mutation frequency.

[0099] Preferably, the iterative solution of the optimization model is performed until the iteration termination condition is triggered, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme, including: performing model initialization, randomly generating multiple antibodies within the design range of a preset operating frequency of the molten salt supply device and the opening and closing degree of each valve as an initial antibody population; calculating the fitness of each antibody in the initial antibody population respectively, and selecting antibodies with a fitness greater than a preset fitness threshold to perform mutation in the optimization direction to obtain mutated antibodies; selecting antibodies with a fitness greater than a preset fitness threshold from the mutated antibodies to perform mutation in the optimization direction again, so as to repeat multiple mutations until the number of iterations is reached, or the fitness function reaches a convergence condition, the iteration is stopped, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme.

[0100] Preferably, the rule for determining the optimization direction is: introduce PID control logic, determine the control point of PID, and determine the optimization direction based on the control point of PID; wherein, the control point of PID of the valve opening on the evaporator system side of the first hot salt pump and the first three-way regulating valve is confirmed based on the dryness of the wet saturated steam; the control point of PID of the valve opening on the superheater system side of the second hot salt pump and the second three-way regulating valve is confirmed based on the temperature of the superheated steam.

[0101] Preferably, the control scheme of the molten salt supply device of the evaporator system and the superheater system with the optimal output, as the optimal molten salt supply device joint control scheme, includes: based on the joint control output of the valve opening of the first hot salt pump and the first three-way regulating valve on the evaporator system side and the joint control output of the valve opening of the second hot salt pump and the second three-way regulating valve on the superheater system side under the PID control logic of the final iterative round, executing the control strategy decoupling of each joint control output, and respectively obtaining the target power of the first hot salt pump, the target valve opening of the first three-way regulating valve on the evaporator system side, the target power of the second hot salt pump and the target valve opening of the second three-way regulating valve on the superheater system side, so as to generate corresponding control schemes as the optimal molten salt supply device joint control scheme.

[0102] An embodiment of the present invention further provides a computer-readable storage medium, on which instructions are stored, which, when executed on a computer, enable the computer to execute the above-mentioned parallel molten salt heated superheated steam generation system control method.

[0103] Those skilled in the art will understand that all or part of the steps in the method for implementing the above-mentioned embodiments can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including several instructions for making a single-chip microcomputer, a chip or a processor execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0104] The optional embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the technical concept of the embodiments of the present invention, the technical scheme of the embodiments of the present invention can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0105] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the embodiments of the present invention, they should also be regarded as the contents disclosed in the embodiments of the present invention.

Claims

1. A parallel molten salt heating superheated steam generation system, characterized in that: The system comprises: The evaporator system and the superheater system connected in sequence are combined to process the produced water from the oil field into steam corresponding to the steam injection demand; wherein, The evaporator system and the superheater system each have a separate molten salt supply device, and the molten salt supply device is used to provide a heat source for the evaporator system and the superheater system; The cold salts of the molten salt supply devices of the evaporator system and the superheater system are collected into the same cold salt recovery device; A control module is used to construct a corresponding salt supply linkage model based on real-time operating conditions, so as to generate an optimal molten salt supply device joint control scheme that meets the steam injection demand based on the salt supply linkage model; The execution modules are respectively arranged on the salt supply pipelines of the molten salt supply devices of the evaporator system and the superheater system, and are used to execute the molten salt supply amount adjustment based on the optimal molten salt supply device joint control scheme.

2. The system according to claim 1, characterized in that The evaporator system includes a plurality of heat exchangers connected in series, so that the produced water after heat exchange in the previous heat exchanger flows into the current heat exchanger to perform secondary heat exchange.

3. The system according to claim 1, characterized in that The system further comprises: a preheating system connected to the front end of the evaporator system; The preheating system is used to preheat produced water and supply the preheated produced water to the evaporator.

4. The system according to claim 1, characterized in that The superheater system comprises: A steam-water separator is connected to the output pipeline of the evaporator system and is used to separate the wet saturated steam output by the evaporator system into steam and water to obtain dry steam and saturated water respectively; A superheater is connected to a pipeline for outputting dry steam from the steam-water separator, and is used to realize heat exchange between the dry steam and hot molten salt in a molten salt supply device of the superheater system, so as to convert the dry steam into superheated dry steam; The mixer is used to collect the superheated dry steam and the saturated water, and is used to generate steam required for steam injection based on the mixing of the superheated dry steam and the saturated water.

5. The system according to claim 4, characterized in that The molten salt supply device of the superheater system comprises: A second salt supply pipeline is arranged in the opposite direction of the dry steam output direction of the steam-water separator, and the second salt supply pipeline is arranged in the same path as the dry steam delivery pipeline in the superheater; The execution module arranged on the superheater system comprises: a second hot salt pump, used for pumping hot salt into the second salt supply pipeline; A second three-way regulating valve disposed on the second salt supply pipeline between the superheater and the second hot salt pump is used to control the hot salt flow rate flowing into the second salt supply pipeline corresponding to the superheater; The molten salt supply device of the superheater system also includes: The second hot salt return pipeline arranged on the third end of the second three-way regulating valve is used to return the excess hot salt that does not flow to the superheater system in the total hot salt flow output by the second hot salt pump to the hot salt storage system.

6. The system according to claim 1, characterized in that The molten salt supply device of the evaporator system comprises: A first salt supply pipeline is provided in the direction from the last heat exchanger of the evaporator system to the first heat exchanger; The execution module arranged on the evaporator system comprises: a first hot salt pump, used for pumping hot salt into the first salt supply pipeline; A first three-way regulating valve disposed on the first salt supply pipeline between the last heat exchanger and the first hot salt pump, for controlling the hot salt flow rate flowing into the first salt supply pipeline corresponding to the evaporator system; The molten salt supply device of the evaporator system also includes: The first hot salt reflux pipeline arranged on the third end of the first three-way regulating valve is used to return the excess hot salt that does not flow to the evaporator system in the total hot salt flow output by the first hot salt pump to the hot salt storage system.

7. The system according to claim 1, characterized in that The control module is configured to: Collecting demand information of steam for steam injection, and taking the demand information of steam for steam injection as a basic constraint; Based on the basic constraints and the artificial immune algorithm, a corresponding optimization model is constructed, wherein the optimization target of the optimization model is to minimize the hot salt consumption; The optimization model is iteratively solved until an iteration termination condition is triggered, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme.

8. The system according to claim 7, characterized in that The method of constructing a corresponding optimization model based on the basic constraints and the artificial immune algorithm includes: The first hot salt pump, the second hot salt pump, the valve opening of the first three-way regulating valve on the evaporator system side, and the valve opening of the second three-way regulating valve on the superheater system side are used as antibody structures; Constructing corresponding fitness functions to evaluate the fitness of each antibody; The corresponding mutation frequency is specified, and the corresponding optimization model is constructed based on the antibody structure, fitness function and mutation frequency.

9. The system according to claim 8, characterized in that The fitness function is expressed as: in, is the fitness value; Total hot salt consumption; , represents the error between the steam quality of steam injection and the target steam quality; and are the target wet steam dryness and the actual wet steam dryness respectively; and are the target superheated steam temperature and the actual superheated steam temperature respectively; and are the preset weights for total hot salt consumption and steam quality error respectively.

10. The system according to claim 7, characterized in that The iterative solution of the optimization model is performed until an iteration termination condition is triggered, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme, including: Perform model initialization, and randomly generate multiple antibodies within the design range of the preset operating frequency of the preset molten salt supply device and the opening and closing degree of each valve as the initial antibody population; The fitness of each antibody in the initial antibody population is calculated respectively, and antibodies with fitness greater than a preset fitness threshold are selected to perform mutation in the optimization direction to obtain mutant antibodies; Among the mutated antibodies, an antibody with a fitness greater than a preset fitness threshold is selected to perform mutation in the optimization direction again, so as to repeat the mutation multiple times until the number of iterations is reached or the fitness function reaches the convergence condition, and the iteration is stopped, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme.

11. The system according to claim 10, characterized in that The rules for determining the optimization direction are: Introduce PID control logic, determine the control action point of PID, and determine the optimization direction based on the control action point of PID; The control action point of the PID of the valve opening of the first hot salt pump and the first three-way regulating valve on the evaporator system side is confirmed based on the dryness of the wet saturated steam; The control action point of the PID of the valve opening of the second hot salt pump and the second three-way regulating valve on the superheater system side is confirmed based on the temperature of the superheated steam.

12. The system according to claim 11, characterized in that The PID control action point of the valve opening of the first hot salt pump and the first three-way regulating valve evaporator system side is based on the confirmation rule of the dryness of the wet saturated steam execution confirmation: in, It is the combined control output of the valve opening of the first hot salt pump and the first three-way regulating valve on the evaporator system side; is the dryness error of wet saturated steam; , and They are proportional gain, integral gain and differential gain respectively.

13. The system according to claim 12, characterized in that The PID control point of the valve opening of the second hot salt pump and the second three-way regulating valve superheater system side is based on the confirmation rule of the superheated steam temperature execution confirmation: in, It is the combined control output of the valve opening of the second hot salt pump and the second three-way regulating valve on the superheater system side; Temperature error of superheated steam for steam injection; , and They are proportional gain, integral gain and differential gain respectively.

14. The system according to claim 3, characterized in that Introduce PID control logic, determine the control action point of PID, and determine the optimization direction based on the control action point of PID, including: Through PID control logic, dynamically correct the variables of antibody solution to optimize steam quality; The fitness value is calculated using the variables adjusted by PID, and the optimal control action point is determined based on the fitness evaluation results; Antibody mutation was performed based on the optimal control point as the corresponding optimization direction.

15. The system according to claim 14, characterized in that The control scheme of the molten salt supply device of the evaporator system and the superheater system with the optimal output, as an optimal molten salt supply device joint control scheme, includes: Based on the joint control output of the valve opening of the first hot salt pump and the first three-way regulating valve on the evaporator system side and the joint control output of the valve opening of the second hot salt pump and the second three-way regulating valve on the superheater system side under the PID control logic of the final iterative round, the control strategy decoupling of each joint control output is performed to obtain the target power of the first hot salt pump, the target valve opening of the first three-way regulating valve on the evaporator system side, the target power of the second hot salt pump and the target valve opening of the second three-way regulating valve on the superheater system side, respectively, to generate the corresponding control scheme as the optimal molten salt supply device joint control scheme.

16. A control method for a parallel molten salt heating superheated steam generation system, characterized in that: The method is applied to the parallel molten salt heating superheated steam generation system according to any one of claims 1 to 15, and the method comprises: Collecting demand information of steam for steam injection, and taking the demand information of steam for steam injection as a basic constraint; Based on the basic constraints and the artificial immune algorithm, a corresponding optimization model is constructed, wherein the optimization target of the optimization model is to minimize the hot salt consumption; The optimization model is iteratively solved until an iteration termination condition is triggered, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme.

17. The method according to claim 16, characterized in that The method of constructing a corresponding optimization model based on the basic constraints and the artificial immune algorithm includes: The first hot salt pump, the second hot salt pump, the valve opening of the first three-way regulating valve on the evaporator system side, and the valve opening of the second three-way regulating valve on the superheater system side are used as antibody structures; Constructing corresponding fitness functions to evaluate the fitness of each antibody; The corresponding mutation frequency is specified, and the corresponding optimization model is constructed based on the antibody structure, fitness function and mutation frequency.

18. The method according to claim 16, characterized in that The iterative solution of the optimization model is performed until an iteration termination condition is triggered, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme, including: Perform model initialization, and randomly generate multiple antibodies within the design range of the preset operating frequency of the preset molten salt supply device and the opening and closing degree of each valve as the initial antibody population; The fitness of each antibody in the initial antibody population is calculated respectively, and antibodies with fitness greater than a preset fitness threshold are selected to perform mutation in the optimization direction to obtain mutant antibodies; Among the mutated antibodies, an antibody with a fitness greater than a preset fitness threshold is selected to perform mutation in the optimization direction again, so as to repeat the mutation multiple times until the number of iterations is reached or the fitness function reaches the convergence condition, and the iteration is stopped, and the optimal control scheme of the molten salt supply device of the evaporator system and the superheater system is output as the optimal molten salt supply device joint control scheme.

19. The method according to claim 18, characterized in that The rules for determining the optimization direction are: Introduce PID control logic, determine the control action point of PID, and determine the optimization direction based on the control action point of PID; The control action point of the PID of the valve opening of the first hot salt pump and the first three-way regulating valve on the evaporator system side is confirmed based on the dryness of the wet saturated steam; The control action point of the PID of the valve opening of the second hot salt pump and the second three-way regulating valve on the superheater system side is confirmed based on the temperature of the superheated steam.

20. The method according to claim 19, characterized in that The control scheme of the molten salt supply device of the evaporator system and the superheater system with the optimal output, as an optimal molten salt supply device joint control scheme, includes: Based on the joint control output of the valve opening of the first hot salt pump and the first three-way regulating valve on the evaporator system side and the joint control output of the valve opening of the second hot salt pump and the second three-way regulating valve on the superheater system side under the PID control logic of the final iterative round, the control strategy decoupling of each joint control output is performed to obtain the target power of the first hot salt pump, the target valve opening of the first three-way regulating valve on the evaporator system side, the target power of the second hot salt pump and the target valve opening of the second three-way regulating valve on the superheater system side, respectively, to generate the corresponding control scheme as the optimal molten salt supply device joint control scheme.

21. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, which, when executed on a computer, enable the computer to execute the parallel molten salt heated superheated steam generation system control method described in any one of claims 1-15.

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