Analysis method and system for surface salt deposition position of heat exchange tube bundle

Abstract

The invention discloses a heat exchange tube bundle surface salt deposition position analysis method and system, and belongs to the technical field of salt deposition position analysis. According to the method, the saturation solubility of NaCl under different temperature conditions is determined according to the internal pressure of the reboiler, the influence of the structure of the heat exchange tube bundle is comprehensively considered in the salt deposition model, meanwhile, the influence of the flow speed on the salt deposition position is concerned on the basis that the saturation solubility of NaCl is considered, and the influence is consistent with the on-site salt deposition position. The water content of water in condensate oil is obtained based on the heat exchange tube bundle temperature field distribution, the fluid field distribution and the saturation solubility of NaCl, then the NaCl content is obtained, the salt deposition position on the surface of the tube bundle can be predicted according to the NaCl content, and a support is provided for process adjustment in the later design and operation process of the tube bundle.

Description

Technical Field

[0001] The present invention belongs to the technical field of salt deposition position analysis, and relates to a method and system for analyzing the salt deposition position on the surface of a heat exchange tube bundle. Background Art

[0002] As an important process in condensate oil treatment, the bottom reboiler of the condensate oil stabilizer generally uses high-temperature positive-pressure distillation to stabilize condensate oil in oilfield condensate oil treatment. In the process flow of the stabilization unit, the three-phase separator further separates the oil, gas, and water from the condensate separated by the metering and production separators. The condensate oil is heated to a certain temperature by the feed heat exchanger and then enters from the top of the condensate oil stabilizer. The light hydrocarbons and liquefied gas dissolved in the condensate oil are cooled by the air cooler at the top of the tower and enter the liquefied gas tower to finely separate the liquefied gas and light hydrocarbon products. A part of the liquid phase at the bottom of the tower enters the reboiler of the stabilizer, is heated, and then returns to the bottom of the tower. Among them, the bottom reboiler of the condensate oil stabilizer mainly exchanges heat with the condensate oil. Usually, the medium inside the reboiler tube bundle is hot kerosene or heat-conducting oil, and the outside of the tube bundle is condensate oil. However, during operation, obvious scaling phenomena occur on the surface of the reboiler tube bundle due to high temperature and high salt. Since the deposition of the scale is closely related to the temperature, flow rate of the heat exchange tube bundle, and the water content in the condensate oil, it is currently impossible to accurately predict the salt deposition position on the tube bundle. In addition, some oilfields introduce a salt washing process, which can alleviate the salt deposition problem to a certain extent, but cannot fundamentally solve the salt deposition situation on the tube bundle.

[0003] Due to the complex influencing factors of salt deposition, including the influence of the surface temperature of the tube bundle, the temperature of the condensate oil, the water content of the condensate oil, the flow rate, and the tube bundle structure, it is very difficult to predict the salt deposition position. Currently, the mainly reference is the NH 4 Cl salt deposition in diesel hydrogenation units, catalytic units, etc. Patent 201810193474.0 discloses an on-line device and process for treating NH 4 Cl salt deposition. This device can treat NH 4 Cl salt deposition on-line through a water injection pipe and an oil-water separator. Among them, the NH 4 Cl salt deposition is mainly caused by the reaction of chlorides and nitrides to generate HCl and NH 3 under high-temperature conditions. When the temperature of the water vapor at the top of the tower is lower than the dew point temperature, condensation water will be generated. As the temperature rises, the water content in the liquid phase decreases, and the dissolved NH4Cl will become saturated and crystallize out. In addition, the NH4Cl salt deposition in the literature is basically based on the critical curve method and the Gibbs reactor method of the process software Aspen plus. The critical curve method requires drawing the Kp-t diagram of NH4Cl, and the Gibbs reactor method does not require calculating the partial pressures of HCl and NH3 and drawing the Kp-t diagram of NH4Cl, which is relatively simple. However, the current methods cannot meet the simulation requirements of salt deposition such as NaCl. Summary of the Invention

[0004] An object of the present invention is to solve the problem in the prior art that it is difficult to accurately obtain the salt deposition position, and to provide an analysis method and system for the salt deposition position on the surface of a heat exchange tube bundle.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] An analysis method for the salt deposition position on the surface of a heat exchange tube bundle proposed by the present invention includes the following steps:

[0007] Obtain the temperature field distribution and fluid field distribution of the heat exchange tube bundle; determine the saturated solubility of NaCl under different temperature conditions according to the pressure inside the reboiler;

[0008] Based on the temperature field distribution, fluid field distribution of the heat exchange tube bundle and the saturated solubility of NaCl, establish a salt deposition model to obtain the water content in the water condensate oil;

[0009] Based on the water content in the water condensate oil, obtain the content of NaCl in the heat exchange tube bundle to determine the salt deposition position.

[0010] Preferably, if the salt deposition component contains NaCl or salt scale of NaCl, then obtain the temperature field distribution and fluid field distribution of the heat exchange tube bundle again.

[0011] Preferably, establish a 1:1 heat exchange tube bundle temperature field model consistent with the reboiler tube bundle. After obtaining the wall thickness and material of the heat exchange tube bundle, combine the thin shell heat transfer modeling method to obtain the temperature field distribution of the heat exchange tube bundle.

[0012] Preferably, the wall thickness of the heat exchange tube bundle is zero. By fixing the inlet temperatures of the heat transfer oil and the water condensate oil in the heat exchange tube bundle, verify with the outlet temperature to determine the accuracy of the constructed model.

[0013] Preferably, select the k-ε two-equation turbulence model under non-isothermal conditions to obtain the fluid field distribution of the heat exchange tube bundle; where k is the turbulent pulsation kinetic energy per unit mass of fluid, and ε is the dissipation rate.

[0014] Preferably, establish the salt deposition model as follows:

[0015]

[0016] Among them, the first term on the left side of the equation is the total water content in the water condensate oil before evaporation within the distance of 0-x, C 0 is the initial water content, ρ is the density, v is the flow velocity of the water condensate oil, t is the time, S is the cross-sectional area of the heat exchange tube bundle; the second term on the left side of the equation is the total evaporation amount of water in the water condensate oil within the distance of 0-x, A is the cross-sectional perimeter of all heat exchange tube bundles greater than the K sp temperature of NaCl; Cw(x) is the water content in the water condensate oil after evaporation within the distance of 0-x.

[0017] Preferably, the NaCl content in the heat exchange tube bundle is obtained as follows:

[0018]

[0019] where C 0 is the initial water content, C NaCl , 0 is the initial NaCl content in water, ρ is the density, v is the flow rate of condensate oil, S is the cross-sectional area of the heat exchange tube bundle, A is the cross-sectional perimeter of all heat exchange tube bundles greater than the NaCl K sp temperature; C w (x) is the water content evaporated from the condensate oil within the distance of 0 - x.

[0020] An analysis system for the salt - deposition position on the surface of a heat exchange tube bundle proposed by the present invention includes:

[0021] A parameter acquisition module, which is used to acquire the temperature field distribution and fluid field distribution of the heat exchange tube bundle; determine the saturated solubility of NaCl under different temperature conditions according to the pressure inside the reboiler;

[0022] A water content acquisition module, which is used to establish a salt - deposition model based on the temperature field distribution, fluid field distribution of the heat exchange tube bundle and the saturated solubility of NaCl, and acquire the water content in the condensate oil;

[0023] An NaCl content acquisition module, which is used to acquire the NaCl content in the heat exchange tube bundle based on the water content in the condensate oil, and determine the salt - deposition position.

[0024] A computer device includes a memory and a processor. When the processor executes the computer program, the steps of the analysis method for the salt - deposition position on the surface of the heat exchange tube bundle are realized.

[0025] A computer - readable storage medium stores a computer program. When the computer program is executed by a processor, the steps of the analysis method for the salt - deposition position on the surface of the heat exchange tube bundle are realized.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] An analysis method for the salt deposition position on the surface of a heat exchange tube bundle proposed by the present invention determines the saturated solubility of NaCl under different temperature conditions based on the pressure inside the reboiler. The salt deposition model provided by the present invention comprehensively considers the structural influence of the heat exchange tube bundle. At the same time, on the basis of considering the saturated solubility of NaCl, it also pays attention to the influence of flow velocity on the salt deposition position, and is consistent with the on-site salt deposition position. Based on the temperature field distribution, fluid field distribution of the heat exchange tube bundle and the saturated solubility of NaCl, the water content in the condensate oil is obtained, and then the NaCl content is obtained. According to its content, the salt deposition position on the tube bundle surface can be predicted, providing support for the process adjustment in the later design and operation of the tube bundle.

[0028] An analysis system for the salt deposition position on the surface of a heat exchange tube bundle proposed by the present invention determines the salt deposition position by dividing the system into a parameter acquisition module, a water content acquisition module and an NaCl content acquisition module. The modular idea is adopted to make each module independent of each other, which is convenient for unified management of each module. Brief Description of the Drawings

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0030] Figure 1 It is a flow chart of the analysis method for the salt deposition position on the surface of the heat exchange tube bundle of the present invention.

[0031] Figure 2 It is a temperature field distribution diagram of the present invention.

[0032] Figure 3 It is a fluid field distribution diagram of the present invention.

[0033] Figure 4 It is a diagram of the saturated solubility of NaCl under different temperature conditions of the present invention.

[0034] Figure 5 It is a temperature distribution diagram of the tube bundle surface at different positions between the second support plate and the first support plate of the present invention.

[0035] Figure 6 It is a temperature distribution diagram of the tube bundle surface at different positions between the second support plate and the first support plate of the present invention.

[0036] Figure 7 It is a calculation result diagram of the salt deposition starting position of the present invention.

[0037] Figure 8This is the analysis system diagram of the salt - deposition position on the heat - exchange tube bundle of the present invention. Detailed implementation manners

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0039] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of the present invention.

[0040] It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0041] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper", "lower", "horizontal", "inner", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed during use, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation of the present invention. In addition, terms such as "first", "second", etc. are only used for descriptive distinction and cannot be understood as indicating or implying relative importance.

[0042] In addition, if the term "horizontal" appears, it does not mean that the component is required to be absolutely horizontal, but it can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but it can be slightly inclined.

[0043] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly specified and limited, if terms such as "set", "installed", "connected", "coupled" are to be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above - mentioned terms in the present invention can be understood according to specific situations.

[0044] The present invention will be further described in detail below with reference to the accompanying drawings:

[0045] A method for analyzing the salt deposition position on the surface of a heat exchange tube bundle proposed by the present invention is as Figure 1 shown, and includes the following steps:

[0046] S1. Obtain the temperature field distribution and fluid field distribution of the heat exchange tube bundle; determine the saturated solubility of NaCl under different temperature conditions according to the pressure inside the reboiler;

[0047] If the salt deposition composition contains NaCl or salt scale of NaCl, then obtain the temperature field distribution and fluid field distribution of the heat exchange tube bundle again.

[0048] Establish a 1:1 heat exchange tube bundle temperature field model consistent with the reboiler tube bundle. After obtaining the wall thickness and material of the heat exchange tube bundle, combine the thin shell heat transfer modeling method to obtain the temperature field distribution of the heat exchange tube bundle.

[0049] The wall thickness of the heat exchange tube bundle is zero. By fixing the inlet temperatures of the heat transfer oil and condensate oil in the heat exchange tube bundle, the accuracy of the constructed model is determined with the outlet temperature as the verification.

[0050] Select the k-ε two-equation turbulence model under non-isothermal conditions to obtain the fluid field distribution of the heat exchange tube bundle; where k is the turbulent pulsation kinetic energy per unit mass of fluid, and ε is the dissipation rate.

[0051] S2. Based on the temperature field distribution, fluid field distribution of the heat exchange tube bundle and the saturated solubility of NaCl, establish a salt deposition model to obtain the water content in the condensate oil;

[0052] Establish the salt deposition model as follows:

[0053]

[0054] Among them, the first term on the left side of the equation is the total water content in the condensate oil before evaporation within the distance of 0-x, C 0 is the initial water content, ρ is the density, v is the flow rate of the condensate oil, t is the time, and S is the cross-sectional area of the heat exchange tube bundle; the second term on the left side of the equation is the total evaporation amount of water in the condensate oil within the distance of 0-x, A is the cross-sectional perimeter of all heat exchange tube bundles greater than the K sp temperature of NaCl; Cw(x) is the water content in the condensate oil after evaporation within the distance of 0-x.

[0055] S3. Based on the water content in the condensate oil, obtain the content of NaCl in the heat exchange tube bundle to determine the salt deposition position.

[0056] Obtain the content of NaCl in the heat exchange tube bundle as follows:

[0057]

[0058] Among them, C 0 is the initial water content, C NaCl , 0 is the initial NaCl content in water, ρ is the density, v is the flow rate of condensate oil, S is the cross-sectional area of the heat exchange tube bundle, A is the cross-sectional perimeter of all heat exchange tube bundles greater than the NaCl K sp temperature; C w (x) is the water content evaporated from the condensate oil within the distance of 0 - x.

[0059] The salt deposition on the on-site tube bundles is serious. The salt deposition location prediction is carried out according to the salt deposition calculation process, which is described below in combination with a case:

[0060] Step 1: Judge the salt deposition component. If it is NaCl or a salt scale mainly composed of NaCl, it can continue. If it is NH4Cl salt deposition, it can be predicted according to the existing methods. Determine the salt scale component as shown in Table 1.

[0061] Table 1 Salt scale composition

[0062] Analysis item mg / kg ％ K content <![CDATA[5.869×10 3 > 0.6 Na content <![CDATA[4.021×10 5 > 40.2 Mg content <![CDATA[1.328×10 2 > 0.01 Fe content <![CDATA[5.295×10 2 > 0.1 <![CDATA[Cl - content]]> <![CDATA[5.899×10 5 > 59.0 <![CDATA[SO 4 2- content]]> <![CDATA[7.992×10 2 10 2 > 0.1

[0063] Step 2: Simulate the temperature field distribution of the heat exchange tube bundle, mainly used to determine the temperature field distribution of the condensate oil, heat transfer oil, and the surface of the heat exchange tube bundle. Here, a 1:1 model consistent with the reboiler tube bundle needs to be established. Considering the small wall thickness of the tube bundle and the strong heat conduction characteristics of the steel used for it, the thin-shell heat transfer modeling technology can be used to model these structures, that is, the geometric thickness is zero, and by fixing the inlet temperatures of the heat transfer oil and condensate oil of the heat exchange tube bundle, and using the outlet temperature as the verification to determine the accuracy of the constructed model. Determine the temperature field distribution of the heat exchange tube bundle, and calculate the temperature field distribution on the surface of the tube bundle according to the thin-shell heat transfer modeling technology, as Figure 2 shown. The inlet temperature of the condensate oil is 50°C, and the outlet temperature of the condensate oil is 77°C. The outlet temperature is consistent with the on-site test results.

[0064] Step 3: Fluid field simulation. During the calculation process, the heat exchange between the outer wall surface of the reboiler and the external atmosphere is not considered. The k-ε two-equation turbulence model widely used under non-isothermal conditions is selected for the flow field calculation, where k is the turbulent pulsation kinetic energy per unit mass of fluid and ε is its dissipation rate, to determine the inlet flow rates of the heat transfer oil and condensate oil, and to determine the reliability of the model calculation by comparing the outlet temperature results with the on-site results. Determine the fluid field. The maximum flow rate of the condensate oil is 0.58 m / s, and the minimum flow rate is only 5.35×10 - 5 m / s. There is a stagnant area at the top of the reboiler, as Figure 3 shown.

[0065] Step 4, Ksp calculation. According to the correspondence table between pressure and boiling point, the boiling points of water at different pressures (MPa): 15.68, 16.66, 17.64, 18.62, and 19.6 can be found first. The saturated solubilities of NaCl (100 g of water) at the corresponding temperatures are as follows Figure 4 shown. By extrapolation, the saturated solubility of NaCl at 117 °C is 40.14 g.

[0066] Step 5, salt deposition model construction. The entire salt deposition process can be simply regarded as follows: during the heat exchange process between the heat transfer oil in the tube side and the condensate oil in the shell side of the reboiler, as the temperature rises, the water in the corresponding condensate oil continuously vaporizes, resulting in the deposition of the salt dissolved in the water on the surface of the tube bundle, and finally forming scale. Therefore, under the conditions of determining parameters such as the surface temperature and flow rate of the tube bundle, the salt deposition on the tube bundle is also related to the vaporization of water in the condensate oil. According to the above salt deposition formula, the salt deposition conditions are not met between the tube sheet and the first support plate. The temperature distribution and fluid distribution on the surface of the tube bundle at different positions between the second support plate and the first support plate are as follows Figure 5 and Figure 6 shown. When the condensate oil enters and flows through the first support plate, salt deposition appears on the surface of the tube bundle at about 806 mm from the tube sheet.

[0067] Combined with the above temperature field and flow field calculation results, if the initial water content is 0.86% and the NaCl content is 34.5 / 1000, the changes in the water content at different positions on the vertical cross-section calculated using the above model are as follows Figure 7 shown (left vertical axis). Using the above critical conditions for NaCl precipitation, the position of NaCl precipitation in the condensate oil is approximately at the surface of the heat exchange tube bundle on the vertical cross-section at about 883.7 mm (indicated by the circle in the right vertical axis).

[0068] Step 6, on-site verification process. The salt deposition situation during the maintenance process is basically consistent with the predicted results. In most cases, salt deposition starts between the first support plate and the second support plate. The farther away from the tube sheet, the higher the corresponding temperature, and the more obvious the salt deposition trend. Eventually, the scale covers the entire tube bundle.

[0069] An analysis system for the salt deposition position on the surface of a heat exchange tube bundle proposed by the present invention is as follows Figure 8 shown, including a parameter acquisition module, a water content acquisition module, and an NaCl content acquisition module;

[0070] The parameter acquisition module is used to acquire the temperature field distribution and fluid field distribution of the heat exchange tube bundle; determine the saturated solubility of NaCl under different temperature conditions according to the pressure inside the reboiler;

[0071] The water content acquisition module is configured to establish a salt deposition model based on the temperature field distribution of the heat exchange tube bundle, the fluid field distribution, and the saturation solubility of NaCl, and acquire the water content in the condensate oil.

[0072] The NaCl content acquisition module is configured to acquire the NaCl content in the heat exchange tube bundle based on the water content in the condensate oil, so as to determine the salt deposition position.

[0073] The terminal device provided by an embodiment of the present invention includes a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps in the above-mentioned method embodiments are implemented. Alternatively, when the processor executes the computer program, the functions of each module / unit in the above-mentioned device embodiments are implemented.

[0074] The computer program may be divided into one or more modules / units, and the one or more modules / units are stored in the memory and executed by the processor to complete the present invention.

[0075] The terminal device may be a computing device such as a desktop computer, a notebook, a palm computer, and a cloud server. The terminal device may include, but is not limited to, a processor and a memory.

[0076] The processor may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0077] The memory may be used to store the computer program and / or module, and the processor realizes various functions of the terminal device by running or executing the computer program and / or module stored in the memory, and calling the data stored in the memory.

[0078] If the modules / units integrated in the terminal device are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such understanding, to implement all or part of the processes in the above-described embodiment methods of the present invention, it can also be completed by a computer program instructing relevant hardware. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the above-described various method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file, or some intermediate form, etc. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disc, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0079] A method for analyzing the salt deposition position on the surface of a heat exchange tube bundle proposed by the present invention. The salt deposition model provided by the present invention comprehensively considers the structural influence of the heat exchange tube bundle. At the same time, on the basis of considering Ksp, it also pays attention to the influence of flow velocity on the salt deposition position, and is consistent with the on-site salt deposition position. It has the following advantages: 1) Simulate the salt deposition process flow and the model calculation process of salt deposition at different positions. 2) Use the thin-shell heat transfer modeling technology to establish the temperature field distribution on the surface of the tube bundle, and use the outlet temperature as the verification condition. 3) Calculate the fluid field by fixing the inlet temperature and flow rate, calculate the outlet temperature, and determine the accuracy of the fluid field. 4) Calculate the moisture content at different positions and the NaCl content.

[0080] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for analyzing the salt - deposition position on the surface of a heat - exchange tube bundle, characterized in that, it includes the following steps: Obtain the temperature - field distribution and fluid - field distribution of the heat - exchange tube bundle; determine the saturated solubility of NaCl under different temperature conditions according to the pressure inside the reboiler; Establish a salt - deposition model based on the temperature - field distribution, fluid - field distribution of the heat - exchange tube bundle and the saturated solubility of NaCl, and obtain the water content in the condensate oil; Based on the water content in the condensate oil, obtain the content of NaCl in the heat - exchange tube bundle to determine the salt - deposition position.

2. The method for analyzing the salt - deposition position on the surface of a heat - exchange tube bundle according to claim 1, characterized in that, if the salt - deposition component contains NaCl or salt scale of NaCl, then obtain the temperature - field distribution and fluid - field distribution of the heat - exchange tube bundle again.

3. The method for analyzing the salt - deposition position on the surface of a heat - exchange tube bundle according to claim 1, characterized in that, Establish a 1:1 heat - exchange tube - bundle temperature - field model consistent with the reboiler tube bundle. After obtaining the wall thickness and material of the heat - exchange tube bundle, combine the thin - shell heat - transfer modeling method to obtain the temperature - field distribution of the heat - exchange tube bundle.

4. The method for analyzing the salt - deposition position on the surface of a heat - exchange tube bundle according to claim 3, characterized in that, The wall thickness of the heat - exchange tube bundle is zero. By fixing the inlet temperatures of the heat - conducting oil and condensate oil in the heat - exchange tube bundle, verify with the outlet temperature to determine the accuracy of the constructed model.

5. The method for analyzing the salt - deposition position on the surface of a heat - exchange tube bundle according to claim 1, characterized in that, Select the k - ε two - equation turbulence model under non - isothermal conditions to obtain the fluid - field distribution of the heat - exchange tube bundle; where k is the turbulent pulsation kinetic energy per unit mass of fluid, and ε is the dissipation rate.

6. The method for analyzing the salt - deposition position on the surface of a heat - exchange tube bundle according to claim 1, characterized in that, Establish the salt - deposition model as follows: Among them, the first term on the left side of the equation is the total water content in the condensate oil before evaporation within the distance of 0 - x, C 0 is the initial water content, ρ is the density, v is the flow rate of the condensate oil, t is the time, and S is the cross-sectional area of the heat exchange tube bundle; the second term on the left side of the equation is the total evaporation amount of water in the condensate oil within the distance of 0 - x, A is the cross-sectional perimeter of all heat exchange tube bundles greater than the NaCl K sp temperature; Cw(x) is the water content in the condensate oil after evaporation within the distance of 0 - x.

7. The method for analyzing the salt - deposition position on the surface of a heat - exchange tube bundle according to claim 1, characterized in that, Obtain the content of NaCl in the heat - exchange tube bundle as follows: Among them, C 0 is the initial water content, C NaCl，0 is the initial NaCl content in water, ρ is the density, v is the flow rate of condensate oil, S is the cross-sectional area of the heat exchange tube bundle, and A is the cross-sectional perimeter of all heat exchange tube bundles greater than the NaCl K sp temperature; C w (x) is the water content evaporated from the condensate oil within the distance of 0 - x.

8. An analysis system for the salt - deposition position on the surface of a heat - exchange tube bundle, characterized in that, it includes: A parameter acquisition module, which is used to obtain the temperature - field distribution and fluid - field distribution of the heat - exchange tube bundle; determine the saturated solubility of NaCl under different temperature conditions according to the pressure inside the reboiler; A water - content acquisition module, which is used to establish a salt - deposition model based on the temperature - field distribution, fluid - field distribution of the heat - exchange tube bundle and the saturated solubility of NaCl, and obtain the water content in the condensate oil; An NaCl - content acquisition module, which is used to obtain the content of NaCl in the heat - exchange tube bundle based on the water content in the condensate oil to determine the salt - deposition position.

9. A computer device, including a memory and a processor, the memory stores a computer program, characterized in that, when the processor executes the computer program, it realizes the steps of the method for analyzing the salt - deposition position on the surface of a heat - exchange tube bundle according to any one of claims 1 to 7.

10. A computer - readable storage medium, the computer - readable storage medium stores a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method for analyzing the salt deposition position on the surface of the heat exchange tube bundle as described in any one of claims 1 to 7.

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