Crude oil cutting simulation method and device, computer equipment and readable storage medium

Abstract

The application discloses a crude oil cutting simulation method and device, computer equipment and a readable storage medium. The method comprises the following steps: based on the molecular composition data of crude oil, simulating the dispersity curve of crude oil molecules and the overlapping degree curve of the cutting point in the preset cutting temperature section; according to the dispersity curve and the overlapping degree curve, determining the proportion of molecules falling into the preset cutting temperature section, so as to determine the simulation side line data of crude oil; comparing the simulation side line data of crude oil with the actual side line data of crude oil, if the deviation between the two is greater than a preset value, adjusting the overlapping degree of the cutting point, until the deviation between the two is less than or equal to the preset value, generating a crude oil cutting model; and using the crude oil cutting model to simulate the crude oil cutting. The dispersity of crude oil molecules and the overlapping degree at the cutting point are considered in the cutting simulation process, so that the cutting simulation result is more in line with the molecular distribution in the actual production process, and the cutting effect is better.

Description

Technical Field

[0001] This application relates to the field of petrochemical production technology, and in particular to a crude oil cutting simulation method, apparatus, computer equipment, and readable storage medium. Background Technology

[0002] Crude oil is a highly complex mixture, with significant differences in physicochemical properties and molecular composition among different types of oil. It's impossible for atmospheric and vacuum distillation to ideally separate every hydrocarbon. In actual production, atmospheric and vacuum distillation processes are always non-idealized. Different side streams often involve exchange between light and heavy fractions, and the distillation units and operating conditions vary slightly between refineries, further complicating the process. Therefore, when simulating refinery atmospheric and vacuum distillation, ideal cutting alone is insufficient to match the actual physicochemical properties of different side streams. Setting the overlap between adjacent side streams to achieve non-ideal cutting is necessary.

[0003] Currently, existing non-ideal cutting techniques for atmospheric and vacuum distillation are achieved by setting a separation factor within the distillation range. This method assumes that the distillation curve overlaps at the beginning, end, and adjacent side streams. The overlapping portion mainly consists of the portion before 5% distillate and after 95% distillate. The separation factor defines the proportion of material within the temperature range near the nominal cut point that enters the adjacent side stream. While this method is simple and quick, and can simulate actual side streams under certain operating conditions, it also has limitations: First, it is not applicable to light-end fractions (below 149°C), and its application effect is poor for vacuum distillates due to excessive overlap. Second, the separation factor is derived from the temperature points where the distillate is 5% and 95% of each side stream, which is too uniform and idealized, making it difficult to match the actual overlapping process. Summary of the Invention

[0004] The purpose of this application is to provide a crude oil cutting simulation method, apparatus, computer equipment, and readable storage medium to solve the problem that the cutting process of the non-ideal atmospheric and vacuum cutting method in the prior art is difficult to match the actual overlapping process, thus affecting the cutting effect.

[0005] To achieve the above objectives, this application provides a crude oil cutting simulation method, comprising:

[0006] Based on the molecular composition data of crude oil, the dispersion curve of crude oil molecules and the overlap curve of cutting points in the preset cutting temperature range are simulated.

[0007] Based on the dispersion curve and the overlap curve, the proportion of molecules that fall into the preset cutting temperature range is determined, so as to determine the simulated side profile data of crude oil.

[0008] The simulated lateral line data of crude oil is compared with the actual lateral line data of crude oil. If the deviation between the two is greater than the preset value, the overlap of the cutting points is adjusted until the deviation is less than or equal to the preset value, and then the crude oil cutting model is generated.

[0009] Crude oil cutting simulation was performed using a crude oil cutting model.

[0010] Furthermore, the actual sideline data of the crude oil includes the cutting temperature point of the sideline, the yield, and the macroscopic physical property data of each sideline.

[0011] Furthermore, before simulating the dispersion curve of crude oil molecules and the overlap curve of cutting points within a preset cutting temperature range based on the molecular composition data of crude oil, the method further includes acquiring the molecular composition data of crude oil, including:

[0012] Obtain physical property data of crude oil, including its density, acid value, and sulfur content;

[0013] Based on the physical property data of crude oil, the most similar crude oil is matched in the molecular-level crude oil database using the cosine similarity method to obtain the corresponding molecular composition data as the molecular composition data of crude oil.

[0014] Furthermore, the dispersion of the crude oil molecules follows a normal distribution, as expressed by the following formula:

[0015]

[0016] In the formula, μ 1 is the molecular boiling point. σ 1 represents the dispersion of crude oil molecules. x 1 represents temperature, and f(x1) represents the density function of a normal distribution.

[0017] Furthermore, the overlap of the cutting points follows a cumulative normal distribution, expressed by the following formula:

[0018]

[0019] In the formula, μ2 is the temperature at the cutting point, σ2 is the overlap of the cutting points, and g(x1) is the density function of the cumulative normal distribution.

[0020] Further, based on the dispersion curve and the overlap curve, the proportion of molecules falling into the preset cutting temperature range is determined, including:

[0021] The molecular proportion that enters the cutting point temperature range can be obtained using the following formula:

[0022] cutW=W×(cutTL_fraction-cutTR_fraction)

[0023] In the formula, cutW is the proportion of molecules entering the cutting point temperature range, W is the content of molecules in crude oil, cutTL_fraction is the proportion of molecules on the right side of the lower cutting temperature cutTL, and cutTR_fraction is the proportion of molecules on the right side of the upper cutting temperature cutTR.

[0024] Furthermore, the overlap of the cutting points is adjusted using a sequential optimization algorithm.

[0025] This application also provides a crude oil cutting simulation device, comprising:

[0026] The curve simulation unit is used to simulate the dispersion curve of crude oil molecules and the overlap curve of cutting points in a preset cutting temperature range based on the molecular composition data of crude oil.

[0027] The simulated lateral line data determination unit is used to determine the proportion of molecules that fall into the preset cutting temperature range based on the dispersion curve and the overlap curve, so as to determine the simulated lateral line data of crude oil.

[0028] The crude oil cutting model generation unit is used to compare the simulated sideline data of crude oil with the actual sideline data of crude oil. If the deviation between the two is greater than the preset value, the overlap of the cutting points is adjusted until the deviation is less than or equal to the preset value, and then the crude oil cutting model is generated.

[0029] The crude oil cutting simulation unit is used to simulate crude oil cutting using a crude oil cutting model.

[0030] This application also provides a computer device, including:

[0031] One or more processors;

[0032] A memory, coupled to the processor, for storing one or more programs;

[0033] When the one or more programs are executed by the one or more processors, the one or more processors implement the crude oil cutting simulation method as described in any of the preceding claims.

[0034] This application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the crude oil cutting simulation method as described in any of the preceding claims.

[0035] Compared to existing technologies, the advantages of this application are as follows:

[0036] This application discloses a crude oil cutting simulation method, apparatus, computer equipment, and readable storage medium. The method includes simulating the dispersion curve of crude oil molecules and the overlap curve of cutting points within a preset cutting temperature range based on the molecular composition data of crude oil; determining the proportion of molecules falling within the preset cutting temperature range based on the dispersion curve and the overlap curve, thereby determining the simulated side profile data of crude oil; comparing the simulated side profile data of crude oil with the actual side profile data of crude oil, and adjusting the overlap of cutting points if the deviation is greater than a preset value until the deviation is less than or equal to the preset value, thereby generating a crude oil cutting model; and performing crude oil cutting simulation using the crude oil cutting model. This application incorporates the dispersion of crude oil molecules and the overlap at cutting points into the cutting simulation process, making the cutting simulation results more consistent with the molecular distribution in the actual production process, resulting in better cutting effects. Attached Figure Description

[0037] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0038] Figure 1 This is a schematic flowchart of a crude oil cutting simulation method provided in a certain embodiment of this application;

[0039] Figure 2 This is a schematic diagram of calculating the ethylbenzene molecular content using the cut point overlap curve and the molecular dispersion curve provided in a certain embodiment of this application;

[0040] Figure 3 This is a comparison diagram of the actual carbon number distribution and the carbon number distribution under ideal cutting conditions in a naphtha fraction of Iranian crude oil provided in a certain embodiment of this application;

[0041] Figure 4 This is a comparison diagram of the actual carbon number distribution of Iranian crude oil and the carbon number distribution under non-ideal cutting, provided in a certain embodiment of this application;

[0042] Figure 5 This is a comparison diagram of the actual carbon number distribution and the carbon number distribution under ideal cutting conditions in a certain embodiment of Venezuelan crude oil naphtha fraction provided in this application;

[0043] Figure 6 This is a comparison diagram of the actual carbon number distribution of Venezuelan crude oil and the carbon number distribution under non-ideal cutting, provided in a certain embodiment of this application;

[0044] Figure 7 This is a schematic diagram of the structure of a crude oil cutting simulation device provided in a certain embodiment of this application;

[0045] Figure 8 This is a schematic diagram of the structure of a computer device provided in a certain embodiment of this application. Detailed Implementation

[0046] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0047] It should be understood that the step numbers used in the text are for ease of description only and are not intended to limit the order in which the steps are performed.

[0048] It should be understood that the terminology used in this application specification is for the purpose of describing particular embodiments only and is not intended to limit the application. As used in this application specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0049] The terms “comprising” and “including” indicate the presence of the described feature, whole, step, operation, element and / or component, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0050] The term “and / or” refers to any combination of one or more of the associated listed items, as well as all possible combinations, and includes these combinations.

[0051] Currently, existing non-ideal cutting techniques for atmospheric and vacuum distillation are achieved by setting a separation factor for the distillation range. This method assumes that there is overlap between the beginning, end, and adjacent side streams of the distillation curve. The overlapping portion mainly consists of the portion before 5% of the distillate and after 95% of the distillate. The separation factor defines the proportion of material entering the adjacent side stream within the temperature range near the nominal cut point. However, this calculation is too uniform and idealized, making it difficult to match the actual overlapping process.

[0052] To address the problems of existing technologies, this embodiment uses a molecular-level crude oil cutting simulation algorithm based on molecular dispersion and overlap to simulate the non-ideal cutting process in actual production. The core of this method lies in proposing that, by adjusting the crude oil molecular dispersion and the overlap of the cutting point, the molecular distribution near the cutting point can be altered. This allows for an approximate simulation of the non-ideal cutting process of a specific atmospheric and vacuum distillation unit in actual production over a wide temperature range, thus achieving the simulation of the actual production cutting of the same type of crude oil by that atmospheric and vacuum distillation unit. It should be noted that crude oil is typically a mixture composed of tens of thousands of molecules. During crude oil distillation, the distillation of each crude oil molecule does not achieve complete separation at its boiling point, but rather gradually distills within a temperature range. Molecular dispersion is defined to describe the temperature at which each molecule begins to evaporate and the temperature at which evaporation ends. In this application, an overlap is defined around each cutting temperature to represent an overlapping interval of crude oil cutting. If the distribution interval of a molecule overlaps with the overlapping interval, this molecule will exist in the regions at both ends of the cutting temperature. A cumulative normal distribution curve is used to define the distribution coefficient to determine the proportion of this molecule on both sides of the cutting temperature. When simulating the cutting of crude oil, the distribution of molecules near the cutting point can be changed by adjusting the inherent properties of crude oil molecules (dispersion, boiling point, etc.) and the overlap of the cutting point. This allows for a near-simulation of the non-ideal cutting process of a certain atmospheric and vacuum distillation unit in actual production over a wide temperature range, thus enabling the simulation of the actual production cutting of the same type of crude oil by that atmospheric and vacuum distillation unit.

[0053] Please see Figure 1 This application provides a crude oil cutting simulation method in one embodiment. For example... Figure 1 As shown, the crude oil cutting simulation method includes steps S10 to S40. The specific details of each step are as follows:

[0054] S10. Based on the molecular composition data of crude oil, simulate the dispersion curve of crude oil molecules and the overlap curve of cutting points in the preset cutting temperature range.

[0055] In one specific embodiment, before performing step S10, the method further includes acquiring molecular composition data of crude oil, including:

[0056] Obtain physical property data of crude oil, including its density, acid value, and sulfur content;

[0057] Based on the physical property data of crude oil, the most similar crude oil is matched in the molecular-level crude oil database using the cosine similarity method to obtain the corresponding molecular composition data as the molecular composition data of crude oil.

[0058] In this embodiment, it is necessary to first collect the actual crude oil property data processed by a certain atmospheric and vacuum distillation unit in the refinery's production process, that is, the crude oil's physical property data, including its density, acid value, and sulfur content. Then, the most similar crude oil is matched in the molecular-level crude oil database using the cosine similarity method to obtain the molecular composition data of that crude oil, including the types and concentrations of molecules. Each crude oil molecule contains single-molecule physical property data such as density and boiling point.

[0059] After obtaining the molecular composition data of crude oil, step S10 requires simulating the dispersion curve of crude oil molecules and the overlap curve of cutting points in the preset cutting temperature range.

[0060] When determining the dispersion curve, the dispersion of molecules is first defined; specifically, a dispersion is defined for each crude oil molecule. The dispersion represents the temperature at which each molecule begins to evaporate and the temperature at which evaporation ends. Assuming the boiling point of a molecule is B, and its dispersion is defined as spread, then the amount of that molecule is dispersed between B ± spread, and its dispersion follows a normal distribution, expressed by the following formula:

[0061]

[0062] In the formula, the expected value μ1 is the boiling point of the molecule, the standard deviation σ1 is the dispersion of crude oil molecules, x1 is the temperature, and f(x1) is the density function of the normal distribution.

[0063] Furthermore, the overlap of the cutting points, Dist_slop, is defined, representing the proportion of molecules whose boiling points are within ±Dist_slop of the cutting point that will enter the cut fraction. A higher overlap indicates a wider molecular distribution range and a greater variety of molecules encompassed in the fraction. The lower cutting temperature limit, cutTL, or the upper cutting temperature limit, cutTR, is determined by the actual values ​​of the simulated fraction. Using the cutting point temperature as the expected value and the overlap (Dist_slop) as the standard deviation, the content distribution of each molecule is calculated using a cumulative normal distribution curve, expressed by the following formula:

[0064]

[0065] In the formula, μ2 is the temperature at the cutting point, σ2 is the overlap of the cutting points, and g(x1) is the density function of the cumulative normal distribution.

[0066] S20. Based on the dispersion curve and the overlap curve, determine the proportion of molecules that fall into the preset cutting temperature range, so as to determine the simulated side profile data of crude oil.

[0067] In this embodiment, determining the proportion of molecules falling into the preset cutting temperature range based on the dispersion curve and the overlap curve includes:

[0068] The molecular proportion that enters the cutting point temperature range can be obtained using the following formula:

[0069] cutW=W×(cutTL_fraction-cutTR_fraction) (3)

[0070] In the formula, cutW is the proportion of molecules entering the cutting point temperature range, W is the content of molecules in crude oil, cutTL_fraction is the proportion of molecules on the right side of the lower cutting temperature cutTL, and cutTR_fraction is the proportion of molecules on the right side of the upper cutting temperature cutTR.

[0071] After obtaining the proportion of molecules falling into the preset cutting temperature range, the distribution pattern of each molecule in the side-line cutting temperature range can be obtained, thereby obtaining all the types and contents of molecules contained in a side-line. Through the mixing model of molecular properties, the macroscopic physical property data of the side-line can be calculated, that is, the simulated side-line data of crude oil can be determined.

[0072] S30. Compare the simulated lateral line data of crude oil with the actual lateral line data of crude oil. If the deviation between the two is greater than the preset value, adjust the overlap of the cutting points until the deviation between the two is less than or equal to the preset value, and then generate the crude oil cutting model.

[0073] When obtaining molecular composition data for crude oil, actual side-stream data is usually acquired simultaneously. Specifically, the actual side-stream data for crude oil includes the cutting temperature point, yield, and macroscopic properties of each side-stream.

[0074] It should be noted that crude oil is fed into an atmospheric and vacuum distillation unit for distillation, and the various products distilled are called side streams. Atmospheric and vacuum distillation units typically have multiple side streams. When performing cut simulations, it is necessary to obtain the cut temperature points (including the lower and upper limits of the cut temperature; each side stream represents a distillate within a temperature range), yields, and macroscopic physical property data (such as density, carbon number (PONA), flash point, etc.) for each side stream. Taking naphtha side stream cuts as an example, in addition to obtaining the cut temperature points and yields, it is also necessary to obtain the macroscopic physical properties of interest for that side stream, such as the carbon number (PONA), to prepare for subsequent cut simulations. The same principle applies to other side stream processes.

[0075] Therefore, in this embodiment, the simulated sideline data of crude oil obtained in step S20 is compared with the actual sideline data of crude oil obtained directly to compare the deviation between the two; if the deviation is greater than a preset value, the overlap of the cutting points is adjusted until the deviation is less than or equal to the preset value, and then the crude oil cutting model is generated.

[0076] In one embodiment, the allowable absolute deviation of the sideline properties is defined as tor. If the calculated deviation is greater than tor, the overlap of the cutting points is fine-tuned by a sequential optimization algorithm. The calculation of the overlap of the cutting points is repeated, and the types and contents of molecules entering the sideline are adjusted until the absolute deviation between the calculated simulated sideline properties and the measured sideline properties is less than tor. In this way, a complete crude oil cutting model is obtained, which includes the overlap of each calibrated sideline cutting point.

[0077] S40. Use crude oil cutting model to simulate crude oil cutting.

[0078] In this step, the cutting model can be used to simulate the actual production of the same type of crude oil.

[0079] In summary, by taking into account the dispersion of crude oil molecules and the overlap at the cutting point in the cutting simulation process, the cutting simulation results are more consistent with the molecular distribution in the actual production process, resulting in better cutting performance.

[0080] To aid understanding, several specific embodiments will be provided below to illustrate the method of this application:

[0081] Scene 1:

[0082] The method provided by this invention was used to simulate the cutting of Iranian crude oil processed in the atmospheric and vacuum distillation unit of a domestic refinery, and GC chromatography was used to detect the content of each molecule in the naphtha sample.

[0083] Specifically, the operational steps for simulating the cutting of Iranian crude oil using this invention mainly include five processes: collecting crude oil data and its side-line data, defining the dispersion of molecules, defining the overlap of cutting points, calculating the proportion of molecules entering the cutting temperature range, and calibrating the overlap of cutting points. The specific processes are as follows:

[0084] (1) Data collection:

[0085] Before conducting crude oil cutting simulation, it is necessary to collect actual crude oil processing data and its side stream data from a certain atmospheric and vacuum distillation unit in the refinery's production process. This invention uses Iranian crude oil from the actual production and processing process of the refinery, whose naphtha side stream cutting temperature point is 15℃-120℃ and the side stream yield is 5.28%. Samples were then collected and their molecular content and carbon number distribution were detected by GC chromatography. The detection results are shown in Table 1.

[0086] Table 1. Measured carbon number distribution of naphtha lateral flow in Iranian crude oil.

[0087]

[0088]

[0089] By collecting crude oil data, similar crude oils are matched in a molecular-level crude oil database to obtain their molecular composition data, including the types and concentrations of molecules. Each crude oil molecule contains single-molecule physical property data such as density and boiling point.

[0090] Taking the cutting of naphtha side streams as an example, the atmospheric and vacuum distillation cutting simulation requires obtaining data such as the cutting temperature point, yield, and PONA value (the number of carbons of interest in that side stream) to prepare for subsequent cutting simulations. The same principle applies to other side stream processes.

[0091] (2) Define the dispersion of molecules:

[0092] Based on the relevant data of each molecule obtained in the first step, the spread of each molecule is defined, and the dispersion curve of each molecule is calculated using formula (1). The spread of ethylbenzene is defined as 14.5. Figure 2 The right side shows the dispersion curve of ethylbenzene. The dispersion curve follows a normal distribution, with its expected value (μ) representing the molecular boiling point (B) and its standard deviation (σ) representing the molecular spread. Figure 2 It can be seen that the boiling point B of ethylbenzene is 136.2℃ and the spread is 14.5. When cutTR is 120℃ and Dist_slop is 10, the curves of cut point overlap and molecular dispersion are shown. The left side is the cut point curve and the right side is the molecular dispersion curve. The area of ​​the gray part is the molecular content.

[0093] (3) Define the overlap of the cutting points:

[0094] The lower limit of the cutting point, cutTL, is set to 15℃, and the upper limit of the cutting point, cutTR, is set to 120℃. The overlap curve of the left and right cutting points is calculated using formula (2) (e.g., the Dist_slop of cutTR is defined as 10). Figure 1 The left side shows the overlap curve of the cutting point. The overlap of the cutting point is calculated using a cumulative normal distribution, with the expected value being the cutting point temperature (cutTL or cutTR) and the standard deviation being the overlap (Dist_slop).

[0095] (4) Calculate the proportion of molecules entering the cutting temperature range:

[0096] Based on the combination of the two distributions in formulas (1) and (2), the proportion of a molecule falling on both sides of the cutting temperature can be determined. Subtracting the proportion of molecules on the right side of cutTL (cutTL_fraction) from the proportion of molecules on the right side of cutTR (cutTR_fraction) gives the final proportion of molecules entering the distillation fraction (e.g., ...). Figure 1 The content of ethylbenzene molecules in crude oil is calculated by multiplying the content of the molecules by the content of the molecules in crude oil (i.e., Formula 3).

[0097] (5) Calibration of the overlap of cutting points:

[0098] The distribution pattern of each molecule in the side-line cutting temperature range can be calculated through steps (3) and (4), thereby obtaining the types and contents of all molecules contained in a side-line. The macroscopic physical property data of the side-line can be calculated through the molecular property mixing model and compared with the side-line properties collected in step (1). The allowable absolute deviation of the side-line carbon number PONA is defined as 0.005. If the calculated deviation is greater than 0.005, the overlap of the cutting points is fine-tuned through the sequential optimization algorithm. The calculation of step (3) is repeated to adjust the types and contents of molecules entering the side-line until the absolute deviation between the calculated side-line properties and the measured side-line carbon number PONA in step (1) is less than 0.005. In this way, a complete crude oil cutting model is obtained, including the overlap of each calibrated side-line cutting point. The optimized naphtha segment overlap setting value is 33, and the carbon number distribution results are shown in Table 3. Among them, Table 2 shows the ideal cutting results of Iranian crude oil without setting overlap and molecular dispersion. Figure 3 A comparison chart of the actual carbon number distribution and the carbon number distribution under ideal cutting in the naphtha fraction of Iranian crude oil (the left side shows the measured percentage of hydrocarbons with different carbon numbers, and the right side shows the percentage of hydrocarbons with different carbon numbers under ideal cutting). Figure 4 This is a comparison chart of the actual carbon number distribution of Iranian crude oil and the carbon number distribution under non-ideal cutting conditions (the left side shows the measured percentage of hydrocarbons with different carbon numbers, and the right side shows the percentage of hydrocarbons with different carbon numbers under non-ideal cutting conditions).

[0099] Table 2 Carbon number distribution of naphtha lateral line under ideal cutting of Iranian crude oil.

[0100] P I O N A C3 0 0 0 0 0 C4 0 0 0 0 0 C5 0.2149 0.1257 0 0.0417 0 C6 0.3147 0.3506 0 0.3659 0.0169 C7 0.3469 0.3902 0 0.7349 0.0824 C8 0.3220 0.6283 0 0.4483 0.1929 C9 0 0.3668 0 0.1879 0 C10 0 0 0 0 0

[0101] Table 3 Carbon number distribution of naphtha lateral lines under non-ideal cutting of Iranian crude oil.

[0102]

[0103]

[0104] Scene 2:

[0105] The method provided by this invention was used to simulate the cutting of Venezuelan crude oil processed in the atmospheric and vacuum distillation unit of a domestic refinery, and GC chromatography was used to detect the content of each molecule in the naphtha sample.

[0106] The operational steps for simulating the cutting of Venezuelan crude oil using this invention mainly include five processes: collecting crude oil data and its lateral line data, defining the dispersion of molecules, defining the overlap of cutting points, calculating the proportion of molecules entering the cutting temperature range, and calibrating the overlap of cutting points. The specific processes are as follows:

[0107] (1) Data collection:

[0108] Before conducting crude oil cutting simulation, it is necessary to collect actual crude oil processing data and its side stream data from a certain atmospheric and vacuum distillation unit in the refinery's production process. This invention uses Venezuelan crude oil from the actual production and processing process of the refinery, whose naphtha side stream cutting temperature point is 15℃-120℃ and the side stream yield is 9.52%. Samples were then collected and their molecular content and carbon number distribution were detected by GC chromatography. The detection results are shown in Table 4.

[0109] Table 4. Measured carbon number distribution of naphtha lateral flow in Venezuelan crude oil.

[0110] P I O N A C3 0.0019 0 0 0 0 C4 0.0743 0.0105 0 0 0 C5 0.3998 0.2780 0 0.0619 0 C6 0.4998 0.6169 0 0.4998 0.0543 C7 0.5645 0.6550 0 1.1519 0.2456 C8 0.5655 1.1186 0 0.8844 0.3779 C9 0.1104 0.6502 0 0.5960 0.0362 C10 0.0010 0.0647 0 0.0010 0

[0111] By collecting crude oil data, similar crude oils are matched in a molecular-level crude oil database to obtain their molecular composition data, including the types and concentrations of molecules. Each crude oil molecule contains single-molecule physical property data such as density and boiling point.

[0112] Taking the cutting of naphtha side streams as an example, the atmospheric and vacuum distillation cutting simulation requires obtaining data such as the cutting temperature point, yield, and PONA value (the number of carbons of interest in that side stream) to prepare for subsequent cutting simulations. The same principle applies to other side stream processes.

[0113] (2) Define the dispersion of molecules:

[0114] Based on the relevant data of each molecule obtained in the first step, the spread of each molecule is defined, and the dispersion curve of each molecule is calculated using formula (1). For example, the spread of ethylbenzene is defined as 14.5. Figure 2 The right side shows the dispersion curve of ethylbenzene. The dispersion curve follows a normal distribution, and its expected value (μ) is the molecular boiling point (B), and the standard deviation (σ) is the molecular spread.

[0115] (3) Define the overlap of the cutting points:

[0116] The lower limit of the cutting point, cutTL, is set to 15℃, and the upper limit of the cutting point, cutTR, is set to 120℃. The overlap curve of the left and right cutting points is calculated using formula (2) (e.g., the Dist_slop of cutTR is defined as 10). Figure 2 The left side shows the overlap curve of the cutting point. The overlap of the cutting point is calculated using a cumulative normal distribution, with the expected value being the cutting point temperature (cutTL or cutTR) and the standard deviation being the overlap (Dist_slop).

[0117] (4) Calculate the proportion of molecules entering the cutting temperature range:

[0118] Based on the combination of the two distributions in formulas (1) and (2), the proportion of a molecule falling on both sides of the cutting temperature can be determined. Subtracting the proportion of molecules on the right side of cutTL (cutTL_fraction) from the proportion of molecules on the right side of cutTR (cutTR_fraction) gives the final proportion of molecules entering the distillation fraction (e.g., ...). Figure 2 (Calculation of ethylbenzene molecular content), then multiplied by the molecular content in crude oil, i.e., formula (3).

[0119] (5) Calibration of the overlap of the cutting points

[0120] The distribution pattern of each molecule in the side-line cutting temperature range can be calculated through steps (3) and (4), thereby obtaining the types and contents of all molecules contained in a side-line. The macroscopic physical property data of the side-line can be calculated through the molecular property mixing model and compared with the side-line properties collected in step (1). The allowable absolute deviation of the side-line carbon number PONA is defined as 0.005. If the calculated deviation is greater than 0.005, the overlap of the cutting points is fine-tuned through the sequential optimization algorithm. The calculation of step (3) is repeated to adjust the types and contents of molecules entering the side-line until the absolute deviation between the calculated side-line properties and the measured side-line carbon number PONA in step (1) is less than 0.005. In this way, a complete crude oil cutting model is obtained, including the overlap of each calibrated side-line cutting point. The optimized naphtha segment overlap setting value is 40, and the carbon number distribution results are shown in Table 6. Table 5 shows the ideal cutting results of Venezuelan crude oil without setting overlap and molecular dispersion. Figure 5 A comparison chart of the actual carbon number distribution and the carbon number distribution under ideal cutting in the naphtha fraction of Venezuelan crude oil (the left side shows the measured percentage of hydrocarbons with different carbon numbers, and the right side shows the percentage of hydrocarbons with different carbon numbers under ideal cutting). Figure 6 This is a comparison chart of the actual carbon number distribution of Venezuelan crude oil and the carbon number distribution under non-ideal cutting conditions (the left side shows the measured percentage of hydrocarbons for different carbon numbers, and the right side shows the percentage of hydrocarbons for different carbon numbers under non-ideal cutting conditions).

[0121] Table 5. Carbon number distribution of naphtha lateral line under ideal cutting of Venezuelan crude oil.

[0122] P I O N A C3 0 0 0 0 0 C4 0 0 0 0 0 C5 0.3998 0.2780 0 0.0619 0 C6 0.4998 0.6169 0 0.4998 0.0543 C7 0.5645 0.6550 0 1.1519 0.2456 C8 0.5920 1.1186 0 0.9394 0.5101 C9 0 0.8914 0 0.1241 0 C10 0 0 0 0 0

[0123] Table 6. Carbon number distribution of naphtha lateral lines under non-ideal cutting of Venezuelan crude oil.

[0124] P I O N A C3 0.0019 0 0 0 0 C4 0.0743 0.0105 0 0.0000 0 C5 0.3998 0.2780 0 0.0619 0.0000 C6 0.4998 0.6169 0 0.4998 0.0543 C7 0.5645 0.6550 0 1.1519 0.2456 C8 0.5610 1.1186 0 0.8793 0.3752 C9 0.1119 0.6456 0 0.6044 0.0387 C10 0 0.0692 0 0.0014 0

[0125] The above implementation examples all generated different molecular distribution results through ideal and non-ideal cutting simulations. As shown in the tables above, the mean deviations under ideal cutting simulations in scenarios one and two are 1.04e... -23.07e -2 The mean deviations under the non-ideal cutting simulations in Scenario 1 and Scenario 2 are 3.94e -4 8.82e -4 This indicates that by introducing the influence of molecular dispersion and cutting point overlap, the molecular cutting simulation results achieved a two-order-of-magnitude improvement in matching with measured data compared to the ideal cutting, demonstrating its ability to effectively simulate the actual atmospheric and vacuum distillation cutting process. On the other hand, the overlap used in scenario two differs by 7 from that obtained in scenario one, indicating that even for different types of crude oil, the overlap used in the algorithm implementation is not significantly different during the cutting simulation of the same atmospheric and vacuum distillation unit.

[0126] Please see Figure 7 One embodiment of this application also provides a crude oil cutting simulation device, comprising:

[0127] Curve simulation unit 01 is used to simulate the dispersion curve of crude oil molecules and the overlap curve of cutting points in a preset cutting temperature range based on the molecular composition data of crude oil.

[0128] The simulated lateral line data determination unit 02 is used to determine the proportion of molecules that fall into the preset cutting temperature range based on the dispersion curve and the overlap curve, so as to determine the simulated lateral line data of crude oil.

[0129] The crude oil cutting model generation unit 03 is used to compare the simulated sideline data of crude oil with the actual sideline data of crude oil. If the deviation between the two is greater than the preset value, the overlap of the cutting points is adjusted until the deviation between the two is less than or equal to the preset value, and then the crude oil cutting model is generated.

[0130] Crude oil cutting simulation unit 04 is used to simulate crude oil cutting using a crude oil cutting model.

[0131] It is understood that the crude oil cutting simulation device described above can implement the crude oil cutting simulation method of the above method embodiments. The options in the above method embodiments are also applicable to this embodiment, and will not be detailed here. The remaining content of this application's embodiments can be referred to the content of the above method embodiments, and will not be repeated in this embodiment.

[0132] Please see Figure 8 One embodiment of this application provides a computer device, including:

[0133] One or more processors;

[0134] A memory, coupled to the processor, for storing one or more programs;

[0135] When the one or more programs are executed by the one or more processors, the one or more processors implement the crude oil cutting simulation method as described above.

[0136] The processor controls the overall operation of the computer device to complete all or part of the steps of the crude oil cutting simulation method described above. The memory stores various types of data to support the operation of the computer device; this data may include, for example, instructions for any application or method operating on the computer device, as well as application-related data. The memory can be implemented using any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk.

[0137] In an exemplary embodiment, the computer device may be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to perform the crude oil cutting simulation method as described in any of the foregoing embodiments and achieve the same technical effects as the methods described above.

[0138] In another exemplary embodiment, a computer-readable storage medium including a computer program is also provided, which, when executed by a processor, implements the steps of the crude oil cutting simulation method as described in any of the foregoing embodiments. For example, the computer-readable storage medium may be the aforementioned memory including the computer program, which may be executed by a processor of a computer device to perform the crude oil cutting simulation method as described in any of the foregoing embodiments and achieve the same technical effects as the described method.

[0139] The above description is the preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.

Claims

1. A crude oil cut simulation method characterized by, The method comprises the following steps: Based on the molecular composition data of crude oil, the dispersion curve of crude oil molecules and the overlap curve of the cutting point in the preset cutting temperature section are simulated; According to the dispersion curve and the overlap curve, the proportion of molecules falling into the preset cutting temperature section is determined to determine the simulated side line data of crude oil; the dispersion of the crude oil molecules satisfies the normal distribution, which is expressed by the following formula: wherein is the molecular boiling point, is the dispersity of the crude oil molecules, is the temperature, is the density function of the normal distribution; The overlap of the cutting point satisfies the cumulative normal distribution, which is expressed by the following formula: wherein is the cut point temperature, is the degree of overlap of the cut point, is the density function of the cumulative normal distribution; The simulated side line data of crude oil is compared with the actual side line data of crude oil. If the deviation between the two is greater than a preset value, the overlap of the cutting point is adjusted until the deviation between the two is less than or equal to the preset value, and a crude oil cutting model is generated; The crude oil cutting model is used for crude oil cutting simulation.

2. The crude oil cut simulation method of claim 1, wherein, The actual side line data of crude oil includes the cutting temperature point, yield and macroscopic physical property data of each side line.

3. The crude oil cut simulation method of claim 1, wherein, Before the step of simulating the dispersion curve of crude oil molecules and the overlap curve of the cutting point in the preset cutting temperature section based on the molecular composition data of crude oil, the method further comprises the following steps of obtaining the molecular composition data of crude oil, which comprises the following steps: Obtaining the physical property data of crude oil, including the density, acid value and sulfur content of crude oil; Based on the physical property data of crude oil, the most similar crude oil is matched in the molecular level crude oil database by the cosine similarity method, and the corresponding molecular composition data is obtained as the molecular composition data of crude oil.

4. The crude oil cut simulation method of claim 1, wherein, According to the dispersion curve and the overlap curve, the proportion of molecules falling into the preset cutting temperature section is determined, which comprises the following steps: The proportion of molecules entering the cutting point temperature range is determined by the following formula: wherein, the proportion of molecules entering the cut point temperature range, the content of the molecule in the crude oil, the lower cut temperature limit the proportion of molecules to the right of the lower cut temperature limit, the proportion of molecules to the right of the upper cut temperature limit cutTR.

5. The crude oil cut simulation method of claim 1, wherein, The overlap of the cutting point is adjusted by using a sequential optimization algorithm.

6. A crude oil cut simulation apparatus, characterized by, The method comprises the following steps: A curve simulation unit is configured to simulate the dispersion curve of crude oil molecules and the overlap curve of the cutting point in the preset cutting temperature section based on the molecular composition data of crude oil; A simulated side line data determination unit is configured to determine the proportion of molecules falling into the preset cutting temperature section according to the dispersion curve and the overlap curve, so as to determine the simulated side line data of crude oil; the dispersion of the crude oil molecules satisfies the normal distribution, which is expressed by the following formula: wherein is the molecular boiling point, is the dispersity of the crude oil molecules, is the temperature, is the density function of the normal distribution; The overlap of the cutting point satisfies the cumulative normal distribution, which is expressed by the following formula: wherein is the cut point temperature, is the degree of overlap of the cut point, is the density function of the cumulative normal distribution; A crude oil cutting model generation unit is configured to compare the simulated side line data of crude oil with the actual side line data of crude oil. If the deviation between the two is greater than a preset value, the overlap of the cutting point is adjusted until the deviation between the two is less than or equal to the preset value, and a crude oil cutting model is generated; A crude oil cutting simulation unit is configured to use the crude oil cutting model for crude oil cutting simulation.

7. A computer device, comprising: The method comprises the following steps: One or more processors; A memory coupled to the processor for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the crude oil cutting simulation method according to any one of claims 1-5.

8. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the crude oil cutting simulation method according to any one of claims 1-5.

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