Evaluation method of energy efficiency and parameter optimization for sand control by perforation in unconsolidated sandstone reservoir

Abstract

The present application provides a kind of unconsolidated sandstone reservoir perforation sand control energy efficiency evaluation and parameter optimization method, the unconsolidated sandstone reservoir perforation sand control energy efficiency evaluation and parameter optimization method includes: step 1, the flow system of perforation sand control well is divided;Step 2, the energy efficiency index of each subsystem divided is calculated;Step 3, the energy consumption gradient and energy consumption density of total flow system are calculated, and energy efficiency index;Step 4, the near well reservoir bottleneck system identification of perforation sand control well is carried out;Step 5, the process parameter of perforation sand control well promotion energy efficiency is optimized and designed.The unconsolidated sandstone reservoir perforation sand control energy efficiency evaluation and parameter optimization method can be used to evaluate the energy utilization efficiency of each flow system and total flow system after perforation completion and different sand control mode combination, and the collaborative optimization design of perforation sand control parameter, to achieve the dual purpose of high yield and energy saving.

Description

Technical Field

[0001] This invention relates to the field of oil and gas development and extraction engineering technology in the oil and gas development industry, and in particular to a method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs. Background Technology

[0002] Oil wells in medium-to-high permeability loose sandstone reservoirs are prone to sand production during production, and sand control measures are generally required. Currently, the main sand control methods used include independent screen pipe sand control, screen pipe gravel packing sand control, screen pipe squeezed gravel packing sand control, fracturing packing sand control, coated sand artificial well wall sand control, and chemical sand fixation.

[0003] In loose sandstone reservoirs, wells often employ casing-perforated completion. Combined with different sand control methods, this results in various additional flow resistance zones at the wellbore and near-wellbore, including screen filter zones, screen-casing annular filling layers, perforation filling layers, external formation compression filling layers, external formation chemical sand-fixing zones, and external formation coated sand filling layers. After perforated sand control wells are put into production, formation fluids flowing through these additional flow zones will experience energy losses such as fracturing losses and velocity variations.

[0004] Before implementing perforation and sand control technologies in medium-to-high permeability loose sandstone reservoirs, both require optimized design of process parameters before on-site construction. Currently, perforation process parameter optimization mainly considers factors such as perforation cost and perforation productivity ratio to optimize perforation diameter, perforation density, permeability, and phase angle, thereby selecting appropriate perforation cartridges and perforation guns. Sand control process parameter optimization mainly focuses on sand control, optimizing parameters such as screen pipe precision, gravel or proppant size, fracture geometry, chemical agents, and coating sand. However, the above-mentioned traditional perforation sand control parameter optimization has the following problems:

[0005] (1) Existing perforation parameter optimization methods do not consider the characteristics of coordination with different sand control methods and the energy loss of flow after production. The optimization of perforation parameters mainly considers perforation cost, casing damage, and perforation completion productivity ratio. The assumption is that the perforation holes are unobstructed. However, in reality, after perforation completion of oil wells in medium-to-high permeability loose sandstone reservoirs, sand control measures are still required. Depending on the sand control method, the perforation holes will be filled with gravel, produced formation sand, or proppant. After the oil well is put into production, it will generate significant resistance, resulting in high energy loss of flow. Existing perforation parameter optimization designs have not yet considered the above-mentioned filling characteristics, and the energy consumption is also unclear.

[0006] (2) Different sand control process parameters do not adequately consider the flow performance and energy efficiency of the sand control area after commissioning. The design of different sand control parameters mainly considers how to effectively block formation sand, but does not adequately consider the flow performance after the formation sand is blocked. This results in sand control wells meeting the requirements for sand blocking effect after commissioning, but having large flow pressure drop and high flow energy consumption in the sand control area. There is currently no means to evaluate the energy efficiency of fluid flow in the sand control area.

[0007] (3) The optimization of perforation completion and sand control process parameters in medium-to-high permeability loose sandstone reservoirs is still in a state of "fighting alone" and lacks coordinated optimization from the perspective of the whole system engineering. The entire perforation-sand control flow system lacks the energy efficiency evaluation methods for each subsystem and the whole system, making it difficult to identify the bottleneck of the entire flow system, resulting in high overall system energy consumption and low energy efficiency.

[0008] Chinese patent application CN118187773A discloses a method for optimizing perforation parameters in double-casing wells based on neural networks. The method includes: obtaining the correlation between perforation parameters and perforated well productivity using a fuzzy comprehensive evaluation method based on sample data of perforation parameters and perforated well productivity; filtering the sample data of perforation parameters and perforated well productivity based on the correlation, and training a perforation completion productivity prediction model using a convolutional neural network; and constructing an optimization strategy network for perforation parameters using the perforation completion productivity prediction model to optimize the perforation parameters used in double-casing perforation completion. This invention can assist operators in quickly and accurately obtaining the optimal combination of double-casing perforation parameters, improving the efficiency of double-casing perforation completion. However, this patent, while describing a method for optimizing perforation parameters in double-casing wells, does not address the evaluation and optimization design of sand control processes. Although the patent utilizes neural networks to optimize perforation parameters in double-casing wells, it does not consider the optimization of perforation parameters under sand control processes.

[0009] Chinese patent application CN112664164B discloses a multi-stage stabilization and long-term sand control technology for high water-cut sandstone reservoirs. This technology includes: Step 1, establishing a reservoir instability model and an instability degree discrimination method; Step 2, implementing reservoir instability prevention based on real-time fluid velocity control; Step 3, performing in-situ stabilization and framework reconstruction of the reservoir using efficient chemical agents coupled with physicochemical processes; Step 4, reconstructing a high-strength, high-permeability artificial wellbore for near-wellbore collapse; Step 5, implementing sand control using high-permeability wellbore anti-clogging filter pipes; and Step 6, restoring reservoir permeability. This multi-stage stabilization and long-term sand control technology effectively reduces reservoir framework sand damage and sand production during high water-cut periods, eliminates near-wellbore blockage after waterflooding and polymer flooding, improves fluid levels, and enables efficient development of loose sandstone reservoirs in oilfields. This patented sand control method involves identifying the degree of reservoir instability and then designing a sand control process using methods such as adjusting the production regime, chemical sand stabilization, artificial wellbore, and sand filter pipes. However, this patent does not optimize the sand control process from an energy perspective, nor does it perform synergistic optimization based on sub-regions of the sand control process.

[0010] Chinese patent application CN115522916A discloses a method for predicting sand production in fractured gas wells in tight sandstone. The method first extracts the inducing factors of sand production in fractured gas wells in tight sandstone and determines their relative importance, constructing a judgment matrix. Based on the sand production inducing factor value scaling, these inducing factors are quantified, and the scaling value of each inducing factor is determined. Then, the weight of the sand production inducing factors in fractured gas wells in tight sandstone is calculated using the analytic hierarchy process (AHP). Finally, a weighted calculation is used to obtain the risk of sand production in fractured gas wells in tight sandstone. Based on the sand production risk assessment model, the risk level of sand production in fractured gas wells in tight sandstone is evaluated. This invention establishes a quantitative standard for sand production inducing factor indicators in fractured gas wells in tight sandstone and establishes a method for predicting the risk of sand production in fractured gas wells in tight sandstone based on the AHP, providing a basis for sand control in gas wells, facilitating the formulation of sand control schemes and the optimization of sand removal processes, and reducing economic losses and time costs caused by sand production in gas wells. This patent primarily addresses methods for predicting sand production in reservoirs, without covering the evaluation and optimization design of sand control processes. While the patent is helpful in developing sand control schemes and optimizing sand removal processes, it does not provide specific design methods.

[0011] The existing technologies described above are significantly different from this invention. A search reveals no literature in the XY category, indicating that this invention is innovative. Since no solution exists in the existing technology to address the technical problem we seek, we have invented a novel method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs. Summary of the Invention

[0012] The purpose of this invention is to provide a method for evaluating the energy utilization efficiency of perforation sand control in loose sandstone reservoirs and optimizing parameters for evaluating the energy utilization efficiency of each flow system and the overall flow system after perforation completion and different combinations of sand control methods.

[0013] The objective of this invention can be achieved through the following technical measures: a method for evaluating and optimizing the energy efficiency of perforation sand control in loose sandstone reservoirs, comprising:

[0014] Step 1: Divide the flow system of the perforated sand control well;

[0015] Step 2: Calculate the energy efficiency index of each subsystem.

[0016] Step 3: Calculate the energy gradient and energy density of the overall flow system, as well as the energy efficiency index.

[0017] Step 4: Identify the near-wellbore reservoir bottleneck system in perforated sand control wells;

[0018] Step 5: Conduct collaborative optimization design of process parameters for improving energy efficiency in perforated sand control wells.

[0019] The objective of this invention can also be achieved through the following technical measures:

[0020] In step 1, based on the characteristics of perforation technology and different sand control methods, the flow system of perforation-sand control technology in loose sandstone reservoirs is divided into perforation subsystem, sand control subsystem, fracture filling subsystem, and original reservoir subsystem.

[0021] In step 1, the perforation subsystem, i.e. the cylindrical flow area of ​​the perforation orifice, is filled with formation sand, gravel or proppant after sand control, depending on the sand control method, to form a porous medium flow area.

[0022] The filled fracture subsystem refers to the filled fractures formed in the fracturing and filling sand control process, which have characteristic parameters such as fracture height, fracture width, fracture length, and filling permeability.

[0023] The sand control subsystem refers to the sand control area other than the perforation hole area and the filling crack, including the screen tube filter layer, the screen sleeve annular filling layer, the gravel filling area of ​​the strata outside the tube, the sand coating filling area of ​​the strata outside the tube, or the chemical sand fixation zone.

[0024] The reservoir subsystem refers to the original storage and flow region from the injection well to the production well.

[0025] Step 2, calculating the energy utilization efficiency index of the flow system includes:

[0026] Based on the schematic diagram of an arbitrary flow element, the equivalent energy consumption of the arbitrary flow element is:

[0027]

[0028] In the formula, ΔE d Equivalent energy consumption, J / s; P0 and P1 are the inlet and outlet pressures of the flow unit, respectively, Pa; q m v0 is the flow rate, kg / s; v1 and v0 are the inlet and outlet flow velocities, respectively, m / s. -1 ρ is the fluid density, kg / m³ 3 ;

[0029] Energy consumption per ton of liquid is calculated using the following formula:

[0030]

[0031] In the formula K Ed Energy consumption per ton of liquid, kJ / t;

[0032] The energy consumption density per ton of liquid is the ratio of energy consumption per ton of liquid to the volume of a unit space, and its expression is as follows:

[0033] K V =K Ed / V

[0034] In the formula K V Energy density per ton of liquid, kJ / m³ 3 / t;

[0035] The unit flow efficiency is the ratio of the energy at the outlet to the energy at the inlet of the flow unit.

[0036]

[0037] In the formula, E1 is the energy at the outlet of the flow unit, and E0 is the energy at the inlet of the flow unit;

[0038] Energy efficiency K E This is the ratio of the equivalent energy consumption of the flow unit to the energy at the inlet, and its expression is as follows:

[0039]

[0040] The expression for energy efficiency K is as follows:

[0041] K = 1 - K E

[0042] Equivalent resistance R F To characterize the proportion of energy consumption of a flow unit to the total flow energy consumption of the entire production system:

[0043]

[0044] In the formula, ΔE dtK represents the equivalent energy consumption of the entire production system, in J / s; K is the energy efficiency, dimensionless; K F For circulation efficiency, dimensionless; K E Energy efficiency, dimensionless; R F It is the equivalent resistance, dimensionless.

[0045] In step 2, the reservoir is divided into 4 subsystems and 9 additional resistance flow regions. The 4 subsystems include a perforation subsystem, a sand control subsystem, a fracture subsystem, and a reservoir subsystem. The 9 additional resistance flow regions and their calculation parameters are as follows:

[0046] a. Perforation and filling zone: calculate the pore diameter, pore length, and pore filling permeability; the zone volume is assumed to be cylindrical.

[0047] b. Screen tube filter belt: calculate the inner diameter of the screen tube, the outer diameter of the screen tube, the length of the screen tube (i.e., the reservoir thickness), and the permeability of the screen tube filter body. The area volume is based on a ring cylinder.

[0048] c. Calculate the inner diameter of the casing and the outer diameter of the screen tube, the length of the screen tube (i.e., the reservoir thickness), and the permeability of the annulus filling. The area volume is calculated as an annular column.

[0049] d. For the sand-filled zone of the annular strata, calculate the inner diameter of the casing, the outer diameter of the screen tube, the length of the screen tube (i.e., the reservoir thickness), and the permeability of the loose sand filling in the annular strata. The regional volume is calculated as a ring column.

[0050] e. For the gravel-filled zone outside the wellbore, calculate the wellbore radius, filling radius, and permeability of the gravel-filled zone. The volume of the zone is calculated as a ring-cylinder.

[0051] f. For the formation outside the pipe coated with sand filling zone, calculate the wellbore radius, filling radius, and permeability of the coated sand filling zone. The area volume is based on a ring cylinder.

[0052] g. Chemical sand-fixing zone outside the pipe: calculate the wellbore radius, sand-fixing radius, and sand-fixing zone permeability. The area volume is calculated as a ring cylinder.

[0053] h. Crack filling zone: Calculate crack height, crack length, crack width, and crack filling permeability. The volume of the zone is calculated as a cuboid.

[0054] i. Reservoir flow region: Calculate the outer boundary radius of the reservoir, the inner boundary radius of the energy storage, and the original permeability of the reservoir. The region volume is calculated as a toroidal column.

[0055] In step 2, the additional resistance flow regions contained in each subsystem are as follows:

[0056] 2a. The perforation subsystem includes a perforation hole filling strip;

[0057] 2b. The sand control subsystem includes screen tube filter belt, screen sleeve annular gravel / proppane filling belt, screen sleeve annular formation sand filling belt, external formation gravel filling belt, external formation coated sand filling belt, and external formation chemical sand fixation belt.

[0058] 2c. The fracture subsystem includes the fracture filling zone;

[0059] 2d. The reservoir subsystem includes the reservoir flow region.

[0060] In step 2, the calculation area included by different sand control technologies for perforated wells is:

[0061] 3a. The independent screen tube sand control process includes perforation hole filling zone, screen tube filter zone, screen sleeve annular sand filling zone, and reservoir flow zone;

[0062] 3b. The screen tube circulating filling sand control process includes perforation hole filling zone, screen tube filter zone, screen sleeve annular gravel / proppane filling zone, and reservoir flow zone;

[0063] 3c. The screen tube extrusion filling sand control process includes perforation hole filling zone, screen tube filter zone, screen sleeve annular gravel / proppane filling zone, external formation gravel filling zone, and reservoir flow zone.

[0064] 3d. The fracturing and sand control process includes perforation hole filling zone, screen filter zone, fracture filling zone, and reservoir flow zone;

[0065] 3e. The sand-coated artificial wellbore sand control technology includes perforation hole filling zone, external formation sand-coated filling zone, and reservoir flow zone;

[0066] 3f. Chemical sand fixation technology includes perforation hole filling zone, external chemical sand fixation zone, and reservoir flow zone.

[0067] In step 2, the specific calculation steps are as follows:

[0068] When calculating the energy efficiency index of each flow subsystem, the following should be included:

[0069] 4a. Based on the implemented sand control technology, determine the corresponding additional resistance area according to the additional resistance area, the subsystem to which it belongs, and the calculation parameters and methods under different perforation sand control technologies;

[0070] 4b. Based on the additional resistance area, its subsystem, calculation parameters, and methods under different perforation sand control processes, calculate the spatial volume of the resistance area using basic data;

[0071] 4c. Calculate the inlet and outlet areas, pressures, and flow velocities for each resistance zone based on production data and geometric parameters;

[0072] 4d. Calculate the equivalent energy consumption, energy consumption gradient, energy consumption density, and energy consumption density per ton of liquid for each resistance region;

[0073] 4e. Based on the relationship between the additional resistance area, the subsystem to which it belongs, and the calculation parameters and methods under different perforation sand control processes, calculate the equivalent energy consumption and space volume of the perforation hole subsystem, sand control subsystem, and fracture subsystem.

[0074] 4f. Calculate the flow resistance, flow efficiency, and energy efficiency of the perforation subsystem, sand control subsystem, and fracture subsystem.

[0075] In step 3, when calculating the energy consumption gradient and energy consumption density of the overall flow system, the energy consumption gradient per ton of fluid in the entire system from the reservoir control boundary to the production well is calculated using the following formula:

[0076]

[0077] The energy density of the total production system is calculated using the following formula:

[0078]

[0079] In the formula K LZ K VZ These are the energy consumption gradient and energy consumption density per ton of liquid in the total system, respectively, in units of J / m³ and J / m³. 3 ;ΔE d(A) ΔE d(B) ΔE d(C) ΔE d(D) The equivalent energy consumption (J / s) for the perforation subsystem, sand control subsystem, fracture subsystem, and reservoir subsystem, respectively; L. A L B L C L D These represent the lengths (in meters) of the perforation subsystem, sand control subsystem, fracture subsystem, and reservoir subsystem in the flow direction, respectively; V A V B V C The flow space volumes, in meters, represent the perforation subsystem, sand control subsystem, and fracture subsystem, respectively.

[0080] In step 3, the energy efficiency K of the total flow system EZ The calculation method is as follows:

[0081]

[0082] The method for calculating the energy efficiency KZ of the total flow system is as follows:

[0083] KZ=1-K BZ

[0084] In the formula, E0D is the flow energy of the reservoir boundary; E ou is the flow energy of the boundary of the total system, i.e., the outlet;

[0085] According to different combinations of sand control methods, the boundary of the total flow system may be the outlet of the screen flow area or the outlet of the filled perforation hole flow area. When calculating specifically, it is necessary to judge and select according to the specific sand control method.

[0086] In step 4, for a specific perforation sand control process, calculate the circulation efficiency or energy utilization efficiency of the perforation subsystem, sand control subsystem, fracture subsystem, and reservoir subsystem according to steps 2 and 3, draw the circulation efficiency of different subsystems and make comparisons. The subsystem with the lowest circulation efficiency is the bottleneck link, that is, the bottleneck system. The circulation bottleneck coefficient R is the highest value R of the equivalent flow resistance in the links of the circulation system FMAX and the average value R of all systems FMIN ratio:

[0087]

[0088] And judge the bottleneck degree of the total system:

[0089] R ≤ the first preset value, the system circulation is excellent, and the bottleneck link can be ignored;

[0090] The first preset value < R ≤ the second preset value, the system circulation is good, but there is a bottleneck link;

[0091] The second preset value < R ≤ the third preset value, the system circulation is average, the bottleneck link is obvious, and it is recommended to take improvement measures;

[0092] R > the third preset value, the system circulation is poor, the bottleneck is serious, and improvement measures need to be taken;

[0093] Among them, the second preset value is greater than the arbitrary preset value and less than the third preset value.

[0094] In step 5, according to the energy utilization efficiency evaluation index of each subsystem, propose a collaborative optimization design method for perforation-sand control parameters based on the principle of balanced flow resistance of each subsystem and the highest energy utilization efficiency of the total system, including the manual trial calculation optimization design method and the orthogonal combination optimization design method.

[0095] In step 5, the manual trial calculation optimization design method includes:

[0096] 1a. Initially design the process parameters according to the conventional design method, and calculate the energy utilization evaluation index of each system and the total system index according to steps 2 and 3;

[0097] 1b. Calculate the circulation bottleneck coefficient R and judge the bottleneck situation;

[0098] 1c. If R < the first preset value, then the current design result is a feasible and reasonable solution; otherwise, determine K. Fmin For the subsystem in question, adjust the design parameters of the subsystem to reduce its energy consumption until R < the first preset value is met.

[0099] 1d. If it is difficult to achieve the condition that R < the first preset value, the condition is relaxed to R < the second preset value, but the total system liquid energy consumption density K is required. VZ >K VZc K VZ K represents the total system energy consumption density per ton of liquid. VZc It is the energy consumption density limit per ton of liquid required at the oilfield site;

[0100] 1e. Repeat the above process until the optimal design is achieved.

[0101] 14. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 12, characterized in that, in step 5, the orthogonal combination optimization design method includes:

[0102] 5a. Based on the selected perforation sand control process type, determine the number of target parameters Nx to be designed;

[0103] 5b. Obtain all feasible values ​​for each objective parameter of Nx;

[0104] 5c. Determine the number of orthogonal design levels Nv for each objective parameter;

[0105] 5d. Use the equal distribution method to obtain the corresponding Nv values ​​for each of the Nx factors;

[0106] 5e. Consult the generated Nx-Nv orthogonal design data table, i.e., the orthogonal optimization design scheme;

[0107] 5f. Calculate the total system energy consumption index for all schemes using steps 2 and 3;

[0108] 5g. Using energy consumption density or energy efficiency per ton of liquid as the evaluation index, the optimal parameter combination is obtained by intuitive analysis.

[0109] The objective of this invention can also be achieved through the following technical measures: a perforation sand control energy efficiency evaluation and parameter optimization system for loose sandstone reservoirs. This system uses the perforation sand control energy efficiency evaluation and parameter optimization method to evaluate the energy utilization efficiency of each flow system and the total flow system after perforation completion and different sand control methods, as well as the collaborative optimization design of perforation sand control parameters.

[0110] This invention presents a method for evaluating the energy efficiency of perforation-based sand control in loose sandstone reservoirs and optimizing its parameters. This method is primarily used to evaluate the energy efficiency of perforated completion sand control systems after commissioning in medium-to-high permeability loose sandstone reservoirs, and to design a synergistic optimization of perforation-sand control parameters. Addressing the shortcomings of existing perforation parameter optimization methods, such as their lack of consideration for the characteristics of different sand control methods and post-commissioning flow energy loss, insufficient consideration of the flow performance and energy efficiency of different sand control process parameters in the post-commissioning sand control area, and the lack of coordinated optimization from a systems engineering perspective in optimizing perforation-based sand control process parameters for medium-to-high permeability loose sandstone reservoirs, this invention proposes a method for evaluating the energy efficiency of perforation-based sand control in loose sandstone reservoirs. This method evaluates the energy utilization efficiency of each flow system and the overall flow system after combining perforated completion and different sand control methods, and designs a synergistic optimization of perforation-based sand control parameters to achieve both high production and energy conservation. Attached Figure Description

[0111] Figure 1 This is a schematic diagram of the subsystem division of a perforated well fracturing and sand control schematic diagram in a specific embodiment of the present invention;

[0112] Figure 2 This is a schematic diagram of a perforated well compression and filling sand-prevention subsystem in a specific embodiment of the present invention;

[0113] Figure 3 This is a schematic diagram of a reservoir subsystem in a specific embodiment of the present invention;

[0114] Figure 4 This is a schematic diagram of the inlet / outlet and energy consumption principle of any flow unit in a specific embodiment of the present invention;

[0115] Figure 5 This is an example of a comparison chart of the flow efficiency of different subsystems in a specific embodiment of the present invention;

[0116] Figure 6 This is a comparison chart of energy efficiency indicators for different combinations of processes in a well, according to a specific embodiment of the present invention.

[0117] Figure 7 This is a comparison diagram of the equivalent process resistance of various subsystems near the well in a specific embodiment of the present invention;

[0118] Figure 8 This is a flowchart of a specific embodiment of the method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to the present invention. Detailed Implementation

[0119] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0120] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, and / or combinations thereof.

[0121] like Figure 8 As shown, Figure 8 This is a flowchart illustrating the energy efficiency evaluation and parameter optimization method for perforation sand control in loose sandstone reservoirs according to the present invention. The method includes:

[0122] Step 1: Divide the flow system of the perforated sand control well. Based on the perforation process and the process characteristics of different sand control methods, the flow system of the perforation-sand control process in loose sandstone reservoirs is divided into a perforation subsystem, a sand control subsystem, a fracture filling subsystem, and a primary reservoir subsystem.

[0123] Step 2: Calculate the energy utilization efficiency index of each flow subsystem and the energy consumption efficiency index of each flow subsystem; based on the equivalent energy consumption, energy consumption gradient, and energy consumption density index, propose the flow resistance, flow efficiency, and energy consumption efficiency index of each subsystem and their calculation methods.

[0124] Step 3: Calculate the energy consumption gradient and energy consumption density of the total flow system, as well as the energy efficiency index; based on the flow resistance, flow efficiency, and energy efficiency indexes of the perforation subsystem, sand control subsystem, fracture filling subsystem, and original reservoir subsystem, propose calculation methods for the energy consumption density, energy consumption density per ton of liquid, flow efficiency, and energy efficiency index of the total flow system.

[0125] Step 4: Identify the near-wellbore reservoir bottleneck system of the perforated sand control well; for a specific perforated sand control process, calculate the flow efficiency or energy efficiency of the perforation subsystem, sand control subsystem, fracture subsystem, and reservoir subsystem based on Step 2 and Step 3, plot the flow efficiency of different subsystems and compare them, and the one with the lowest flow efficiency is the bottleneck link.

[0126] Step 5: Conduct collaborative optimization design of process parameters for improving the energy efficiency of perforated sand control wells. Based on the energy efficiency evaluation indicators of each subsystem, a collaborative optimization design method for perforation-sand control parameters is proposed, based on the principle of balanced flow resistance of each subsystem and the highest overall system energy efficiency.

[0127] This invention considers the evaluation of the energy utilization efficiency of each flow subsystem and the total flow system after the perforation and sand control technology in loose sandstone reservoirs is put into production, and the co-optimization method of perforation-sand control parameters that considers the balance of flow energy consumption of each system and the high energy utilization efficiency of the total system, thereby improving the overall energy consumption of oil wells and achieving energy saving and consumption reduction under high production efficiency.

[0128] The following are several specific embodiments of the application of the present invention.

[0129] Example 1

[0130] In a specific embodiment 1 of the present invention, the method for evaluating the energy efficiency and optimizing the parameters of perforation sand control in loose sandstone reservoirs includes the following steps:

[0131] Step 1: Based on the characteristics of perforation technology and different sand control methods, the flow system of the perforation-sand control process in loose sandstone reservoirs is divided into a perforation subsystem, a sand control subsystem, a fracture filling subsystem, and a primary reservoir subsystem. Based on equivalent energy consumption, energy gradient, and energy density indices, the flow resistance, flow efficiency, and energy efficiency indices of each subsystem and their calculation methods are proposed. The specific implementation steps are as follows:

[0132] (1) Method for classifying the flow system of perforated sand control wells

[0133] The perforation-sand control process flow system for loose sandstone reservoirs is divided into a perforation subsystem, a sand control subsystem, a fracture filling subsystem, and a primary reservoir subsystem, such as... Figure 1 As shown.

[0134] The perforation subsystem refers to the cylindrical flow zone of the perforation orifice. After sand control, depending on the sand control method, it is filled with formation sand, gravel, or proppant, forming a porous media flow zone, such as... Figure 1 As shown.

[0135] The fracture filling subsystem refers to the fractures formed during the fracturing and sand control process, characterized by parameters such as fracture height, width, length, and filling permeability. Figure 1 As shown.

[0136] The sand control subsystem refers to the sand control area excluding the perforation area and the filling cracks. It may include the screen filter layer, the screen sleeve annular filling layer, the gravel-filled area outside the screen, the sand-coated area outside the screen, or the chemical sand-fixing zone. Figure 2 As shown.

[0137] The reservoir subsystem refers to the original storage and flow region from the injection well to the production well, such as... Figure 3 As shown.

[0138] (2) Energy utilization efficiency index of flow system

[0139] according to Figure 4 The schematic diagram of an arbitrary flow element shown illustrates the equivalent energy consumption of that flow element as follows:

[0140]

[0141] In the formula, ΔE d Equivalent energy consumption, J / s; P0 and P1 are the inlet and outlet pressures of the flow unit, respectively, Pa; q m v0 is the flow rate, kg / s; v1 and v0 are the inlet and outlet flow velocities, respectively, m / s. -1 ρ is the fluid density, kg / m³ 3 .

[0142] The energy consumption per ton of liquid is calculated using the following formula:

[0143]

[0144] In the formula K Ed Energy consumption per ton of liquid, kJ / t.

[0145] The energy consumption density per ton of liquid is proposed as the ratio of energy consumption per ton of liquid to the volume of a unit space, and its expression is as follows:

[0146] K V =K Ed / V

[0147] In the formula K V Energy density per ton of liquid, kJ / m³ 3 / t.

[0148] The unit flow efficiency is defined as the ratio of energy at the outlet to energy at the inlet of the flow unit.

[0149]

[0150] The energy efficiency KE is proposed to be the ratio of the equivalent energy consumption of the flow unit to the energy at the inlet, and its expression is as follows:

[0151]

[0152] The expression for energy efficiency K is proposed as follows:

[0153] K = 1 - K E

[0154] The equivalent resistance RF is proposed as the proportion of the energy consumption of the flow unit to the total flow energy consumption of the entire production system.

[0155]

[0156] In the formula, ΔE dtK represents the equivalent energy consumption of the entire production system, in J / s; K is the energy efficiency, dimensionless; K F For circulation efficiency, dimensionless; K E Energy efficiency, dimensionless; R F It is the equivalent resistance, dimensionless.

[0157] (3) Calculation of energy efficiency index of each flow subsystem

[0158] Based on the additional resistance regions, subsystems, calculation parameters, and methods for different perforation sand control technologies shown in Table 1, calculate the spatial volume of the flow region according to the sand control technology. In the table, ■ represents the perforation subsystem, ● represents the sand control subsystem, and ★ represents the fracture subsystem. This represents the reservoir subsystem.

[0159] Table 1. Additional resistance zones, associated subsystems, calculation parameters, and methods for different perforation sand control technologies.

[0160]

[0161]

[0162] The specific calculation steps are as follows:

[0163] a. Based on the implemented sand control technology, determine the corresponding additional resistance area in Table 1;

[0164] b. Calculate the spatial volume of the resistance zone based on the basic data shown in Table 1;

[0165] c. Calculate the inlet and outlet areas, pressures, and flow velocities of each resistance zone based on production data and geometric parameters;

[0166] d. Calculate the equivalent energy consumption, energy consumption gradient, energy consumption density, and energy consumption density per ton of liquid for each resistance region;

[0167] e. Based on the relationships in Table 1, calculate the equivalent energy consumption and space volume of the perforation subsystem, sand control subsystem, and fracture subsystem by superimposing the data.

[0168] f. Calculate the flow resistance, flow efficiency, and energy efficiency of the perforation subsystem, sand control subsystem, and fracture subsystem.

[0169] Step 2: Based on the flow resistance, flow efficiency, and energy efficiency indices of the perforation subsystem, sand control subsystem, fracture filling subsystem, and original reservoir subsystem, propose the energy density and energy density per ton of liquid for the overall flow system, as well as the calculation methods for the flow efficiency and energy efficiency indices. The specific implementation steps are as follows:

[0170] (1) Calculation of energy consumption gradient and energy consumption density of the overall system

[0171] The energy consumption gradient per ton of fluid in the entire system from the reservoir control boundary to the production well is calculated using the following formula:

[0172]

[0173] The energy density of the total production system is calculated using the following formula:

[0174]

[0175] In the formula K LZ K VZ These are the energy consumption gradient and energy consumption density per ton of liquid in the total system, respectively, in units of J / m and J / m3; ΔE d(A) ΔE d(B) ΔE d(C) ΔE d(D) The equivalent energy consumption (J / s) for the perforation subsystem, sand control subsystem, fracture subsystem, and reservoir subsystem, respectively; L. A L B L C L D These represent the lengths (in meters) of the perforation subsystem, sand control subsystem, fracture subsystem, and reservoir subsystem in the flow direction, respectively; V A V B V C The flow space volumes, in meters, represent the perforation subsystem, sand control subsystem, and fracture subsystem, respectively.

[0176] It should be noted that when calculating energy consumption density, the calculated energy consumption density is extremely small because the volume of the reservoir flow system is orders of magnitude larger than that of other subsystems. In order to facilitate the comparison of the total system energy consumption density under different construction parameters, the reservoir volume is ignored in the calculation.

[0177] (2) Calculation of the overall system's energy efficiency index

[0178] A method for calculating the overall system energy efficiency is proposed:

[0179]

[0180] A method for calculating the overall system energy efficiency is proposed:

[0181] KZ=1-K EZ

[0182] In the formula, E 0D E represents the flow energy at the reservoir boundary. ou This refers to the flowing energy at the boundary of the entire system, i.e., the outlet.

[0183] According to different sand control method combinations, the inner boundary of the total system may be the outlet of the screen flow area or the outlet of the filled perforation hole flow area. When calculating specifically, it is necessary to judge and select according to the specific sand control method.

[0184] Step 3: According to the energy utilization efficiency evaluation indexes of each subsystem, propose a collaborative optimization design method for perforation-sand control parameters based on the principle of balanced flow resistance of each subsystem and the highest energy utilization efficiency of the total system, as well as a bottleneck system evaluation and identification method for the entire flow system. The specific implementation steps are as follows:

[0185] (1) Identification method for the near-wellbore reservoir bottleneck system of perforated sand control wells

[0186] For a specific perforated sand control process, calculate the flow efficiency or energy utilization efficiency of the perforation subsystem, sand control subsystem, fracture subsystem, and reservoir subsystem respectively according to the methods in Steps 1 and 2, and draw a comparison of the flow efficiencies of different subsystems as shown in Figure 5 The subsystem with the lowest flow efficiency is the bottleneck link. In the figure, the completion system refers to the perforation subsystem.

[0187] Definition: The flow bottleneck coefficient R is the ratio of the highest value of the equivalent flow resistance in the links of the flow system (excluding the reservoir subsystem) to the average value of all systems

[0188]

[0189] Use the following criteria to judge the bottleneck degree of the total system:

[0190] R ≤ 1.25, the system has excellent fluidity, and the bottleneck link can be ignored

[0191] 1.25 < R ≤ 1.5, the system has good fluidity, but there is a bottleneck link

[0192] 1.5 < R ≤ 1.75, the system has average fluidity, the bottleneck link is obvious, and it is recommended to take improvement measures

[0193] R > 1.75, the system has poor fluidity, the bottleneck is serious, and improvement measures need to be taken

[0194] (2) Collaborative optimization design method for process parameters to improve the energy utilization efficiency of perforated sand control wells

[0195] Propose two collaborative optimization design methods for process parameters to improve the energy utilization efficiency of perforated sand control wells. The design principle is to balance the flow performance of each subsystem and maximize the energy utilization efficiency of the total system (under the premise of meeting the production requirements).

[0196] Method A: Manual trial calculation optimization design method

[0197] a. Design the process parameters in the preliminary manner according to the conventional design method, and use steps S1, S2 and S3 to calculate the energy consumption evaluation index of each system and the overall system index.

[0198] b. Calculate the bottleneck coefficient R to determine the bottleneck status.

[0199] c. If R < 1.25, then the current design result is a feasible and reasonable solution; otherwise, determine K. Fmin For the subsystem in question, adjust the design parameters of the subsystem to reduce its energy consumption until R < 1.25.

[0200] d. If it is difficult to achieve the condition R < 1.25, the condition can be relaxed to R < 1.5, but the total system energy consumption density per ton of liquid K must still be maintained. VZ >K VZc .

[0201] e. Repeat the above process until the optimal design is achieved.

[0202] Method B: Orthogonal combinatorial optimization design method

[0203] a. Determine the number of target parameters Nx to be designed based on the selected perforation sand control process type.

[0204] b. Obtain all feasible values ​​for each objective parameter of Nx.

[0205] c. Determine the number of orthogonal design levels Nv for each objective parameter.

[0206] d. Use the equal distribution method to obtain the corresponding Nv values ​​for each of the Nx factors.

[0207] e. Consult the generated Nx-Nv orthogonal design data table, i.e., the orthogonal optimization design scheme.

[0208] e. Calculate the total system energy consumption index for all schemes using steps S1, S2, and S3.

[0209] f. Using energy consumption density per ton of liquid or energy efficiency as evaluation indicators, the optimal parameter combination is obtained by intuitive analysis.

[0210] Example 2

[0211] In a specific embodiment 2 of the present invention, orthogonal combinatorial optimization design method is used for parameter optimization. The basic data of a certain well used are shown in Table 2.

[0212] Table 2 Basic Data of a Certain Well

[0213] Data Items numerical values Data Items numerical values Oil well type Production wells Select stratum sand 7-31-246 / 1# / 0 Oil well type Vertical shaft Median grain size of formation sand / mm 0.1444 Well inclination angle / o 5.98 Formation sand uniformity coefficient 1.5777 Basic well completion methods Perforation Formation sand fineness content / % 5.3805 Sand control process types Fracturing and Sand Control Liquid production rate (t / d) 23.33 Reservoir control radius / m 200 Bottom hole flowing pressure / MPa 6.68 Wellbore size / mm 244.5 Moisture content / % 82.08 Outer diameter / inner diameter of casing / mm 177.8 Liquid phase volumetric sand content / ‰ 0.01 Crude oil properties GO8-16C7 Crude oil density (kg / m³) 943.63 Crude oil viscosity / mPa.s 1712.13 Crude oil volume coefficient 1.035

[0214] The well employs fracturing and filling for sand control. The optimized design target parameters and feasible values ​​are shown in Table 3.

[0215] Table 3. List of feasible values ​​for target parameters in the optimized design of fracturing and sand control filling.

[0216]

[0217] Based on 9 factors and 5 value levels, the factor level data table is shown in Table 4.

[0218] Table 4. Distribution of values ​​for all factors and levels

[0219]

[0220] After generating the orthogonal array, calculate the energy consumption index for all schemes, including the energy consumption density comparison chart for ton-of-liquid as shown below. Figure 6 As shown.

[0221] The optimal design scheme combination parameters obtained using the intuitive analysis method are shown in Table 5, and the equivalent drag comparison diagram is shown below. Figure 7 As shown.

[0222] Table 5 Optimal Result Data Table

[0223]

[0224]

[0225] This invention proposes a method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs. It is used to evaluate the energy utilization efficiency of each flow system and the overall flow system after perforation completion and different combinations of sand control methods, as well as the synergistic optimization design of perforation sand control parameters. Its features and beneficial effects include:

[0226] (1) Based on basic process parameters, it can quickly and easily calculate the perforation subsystem, sand control subsystem, fracture subsystem, and the flow energy consumption, flow resistance, energy efficiency, and other indicators of the entire system after perforation completion and sand control in oil wells. This helps to identify bottleneck areas in the entire flow system and guide the improvement and optimization of process parameters.

[0227] (2) The optimization method of perforation parameters is combined with different sand control methods by using energy efficiency evaluation and collaborative optimization methods. The situation of perforation filling gravel, production of formation sand or support caused by different sand control methods is considered. This avoids the bottleneck effect of perforation filling flow and improves the rationality of perforation parameter design.

[0228] (3) This ensures that the sand control parameters not only consider the sand-blocking effect, but also the flow performance and energy efficiency of the sand control area after commissioning. It achieves coordinated optimization of perforation and sand control parameters from the perspective of the whole system engineering, thereby improving the overall energy efficiency of the system.

[0229] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0230] Except for the technical features described in the specification, all other technologies are known to those skilled in the art.

Claims

1. A method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs, characterized in that, The energy efficiency evaluation and parameter optimization methods for perforation sand control in loose sandstone reservoirs include: Step 1: Divide the flow system of the perforated sand control well; Step 2: Calculate the energy efficiency index of each subsystem. Step 3: Calculate the energy gradient and energy density of the overall flow system, as well as the energy efficiency index. Step 4: Identify the near-wellbore reservoir bottleneck system in perforated sand control wells; Step 5: Conduct collaborative optimization design of process parameters for improving energy efficiency in perforated sand control wells.

2. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 1, characterized in that, In step 1, based on the characteristics of perforation technology and different sand control methods, the flow system of perforation-sand control technology in loose sandstone reservoirs is divided into perforation subsystem, sand control subsystem, fracture filling subsystem, and original reservoir subsystem.

3. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 2, characterized in that, In step 1, the perforation subsystem, i.e. the cylindrical flow area of ​​the perforation orifice, is filled with formation sand, gravel or proppant after sand control, depending on the sand control method, to form a porous medium flow area. The filled fracture subsystem refers to the filled fractures formed in the fracturing and filling sand control process, which have characteristic parameters such as fracture height, fracture width, fracture length, and filling permeability. The sand control subsystem refers to the sand control area other than the perforation hole area and the filling crack, including the screen tube filter layer, the screen sleeve annular filling layer, the gravel filling area of ​​the strata outside the tube, the sand coating filling area of ​​the strata outside the tube, or the chemical sand fixation zone. The reservoir subsystem refers to the original storage and flow region from the injection well to the production well.

4. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 1, characterized in that, Step 2, calculating the energy utilization efficiency index of the flow system includes: Based on the schematic diagram of an arbitrary flow element, the equivalent energy consumption of the arbitrary flow element is: In the formula, ΔE d Equivalent energy consumption, J / s; P0 and P1 are the inlet and outlet pressures of the flow unit, respectively, Pa; q m v0 is the flow rate, kg / s; v1 and v0 are the inlet and outlet flow velocities, respectively, m / s. -1 ρ is the fluid density, kg / m³ 3 ; Energy consumption per ton of liquid is calculated using the following formula: In the formula K Ed Energy consumption per ton of liquid, kJ / t; The energy consumption density per ton of liquid is the ratio of energy consumption per ton of liquid to the volume of a unit space, and its expression is as follows: K V =K Ed / V In the formula K V Energy density per ton of liquid, kJ / m³ 3 / t; The unit flow efficiency is the ratio of the energy at the outlet to the energy at the inlet of the flow unit. In the formula, E1 is the energy at the outlet of the flow unit, and E0 is the energy at the inlet of the flow unit; Energy efficiency K E This is the ratio of the equivalent energy consumption of the flow unit to the energy at the inlet, and its expression is as follows: The expression for energy efficiency K is as follows: K=1-K E Equivalent resistance R F To characterize the proportion of energy consumption of a flow unit to the total flow energy consumption of the entire production system: In the formula, ΔE dt K represents the equivalent energy consumption of the entire production system, in J / s; K is the energy efficiency, dimensionless; K F For circulation efficiency, dimensionless; K E Energy efficiency, dimensionless; R f It is the equivalent resistance, dimensionless.

5. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 1, characterized in that, In step 2, the reservoir is divided into 4 subsystems and 9 additional resistance flow regions. The 4 subsystems include a perforation subsystem, a sand control subsystem, a fracture subsystem, and a reservoir subsystem. The 9 additional resistance flow regions and their calculation parameters are as follows: a. Perforation and filling zone: calculate the pore diameter, pore length, and pore filling permeability; the zone volume is assumed to be cylindrical. b. Screen tube filter belt: calculate the inner diameter of the screen tube, the outer diameter of the screen tube, the length of the screen tube (i.e., the reservoir thickness), and the permeability of the screen tube filter body. The area volume is based on a ring cylinder. c. Calculate the inner diameter of the casing and the outer diameter of the screen tube, the length of the screen tube (i.e., the reservoir thickness), and the permeability of the annulus filling. The area volume is calculated as an annular column. d. For the sand-filled zone of the annular strata, calculate the inner diameter of the casing, the outer diameter of the screen tube, the length of the screen tube (i.e., the reservoir thickness), and the permeability of the loose sand filling in the annular strata. The regional volume is calculated as a ring column. e. For the gravel-filled zone outside the wellbore, calculate the wellbore radius, filling radius, and permeability of the gravel-filled zone. The volume of the zone is calculated as a ring-cylinder. f. For the formation outside the pipe coated with sand filling zone, calculate the wellbore radius, filling radius, and permeability of the coated sand filling zone. The area volume is based on a ring cylinder. g. Chemical sand-fixing zone outside the pipe: calculate the wellbore radius, sand-fixing radius, and sand-fixing zone permeability. The area volume is calculated as a ring cylinder. h. Crack filling zone: Calculate crack height, crack length, crack width, and crack filling permeability. The volume of the zone is calculated as a cuboid. i. Reservoir flow region: Calculate the outer boundary radius of the reservoir, the inner boundary radius of the energy storage, and the original permeability of the reservoir. The region volume is calculated as a toroidal column.

6. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 5, characterized in that, In step 2, the additional resistance flow regions contained in each subsystem are as follows: 2a. The perforation subsystem includes a perforation hole filling strip; 2b. The sand control subsystem includes screen tube filter belt, screen sleeve annular gravel / proppane filling belt, screen sleeve annular formation sand filling belt, external formation gravel filling belt, external formation coated sand filling belt, and external formation chemical sand fixation belt. 2c. The fracture subsystem includes the fracture filling zone; 2d. The reservoir subsystem includes the reservoir flow region.

7. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 6, characterized in that, In step 2, the calculation area included by different sand control technologies for perforated wells is: 3a. The independent screen tube sand control process includes perforation hole filling zone, screen tube filter zone, screen sleeve annular sand filling zone, and reservoir flow zone; 3b. The screen tube circulating filling sand control process includes perforation hole filling zone, screen tube filter zone, screen sleeve annular gravel / proppane filling zone, and reservoir flow zone; 3c. The screen tube extrusion filling sand control process includes perforation hole filling zone, screen tube filter zone, screen sleeve annular gravel / proppane filling zone, external formation gravel filling zone, and reservoir flow zone. 3d. The fracturing and sand control process includes perforation hole filling zone, screen filter zone, fracture filling zone, and reservoir flow zone; 3e. The sand-coated artificial wellbore sand control technology includes perforation hole filling zone, external formation sand-coated filling zone, and reservoir flow zone; 3f. Chemical sand fixation technology includes perforation hole filling zone, external chemical sand fixation zone, and reservoir flow zone.

8. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 7, characterized in that, In step 2, the specific calculation steps are as follows: When calculating the energy efficiency index of each flow subsystem, the following should be included: 4a. Based on the implemented sand control technology, determine the corresponding additional resistance area according to the additional resistance area, the subsystem to which it belongs, and the calculation parameters and methods under different perforation sand control technologies; 4b. Based on the additional resistance area, its subsystem, calculation parameters, and methods under different perforation sand control processes, calculate the spatial volume of the resistance area using basic data; 4c. Calculate the inlet and outlet areas, pressures, and flow velocities for each resistance zone based on production data and geometric parameters; 4d. Calculate the equivalent energy consumption, energy consumption gradient, energy consumption density, and energy consumption density per ton of liquid for each resistance region; 4e. Based on the relationship between the additional resistance area, the subsystem to which it belongs, and the calculation parameters and methods under different perforation sand control processes, calculate the equivalent energy consumption and space volume of the perforation hole subsystem, sand control subsystem, and fracture subsystem. 4f. Calculate the flow resistance, flow efficiency, and energy efficiency of the perforation subsystem, sand control subsystem, and fracture subsystem.

9. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 1, characterized in that, In step 3, when calculating the energy consumption gradient and energy consumption density of the overall flow system, the energy consumption gradient per ton of fluid in the entire system from the reservoir control boundary to the production well is calculated using the following formula: The energy density of the total production system is calculated using the following formula: In the formula K LZ K VZ These are the energy consumption gradient and energy consumption density per ton of liquid in the total system, respectively, in units of J / m³ and J / m³. 3 ;ΔE d(A) ΔE d(B) ΔE d(C) ΔE d(D) Equivalent energy consumption (J / S) for the perforation subsystem, sand control subsystem, fracture subsystem, and reservoir subsystem, respectively; L. A L B L C L D These represent the lengths (in meters) of the perforation subsystem, sand control subsystem, fracture subsystem, and reservoir subsystem in the flow direction, respectively; V A V B V C The flow space volumes, in meters, represent the perforation subsystem, sand control subsystem, and fracture subsystem, respectively.

10. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 1, characterized in that, In step 3, the energy efficiency K of the total flow system EZ The calculation method is as follows: The method for calculating the energy efficiency KZ of the total flow system is as follows: KZ=1-K EZ In the formula, E 0D E represents the flow energy at the reservoir boundary. ou This refers to the flowing energy at the boundary of the entire system, i.e., the outlet. According to different combinations of sand control methods, the inner boundary of the total flow system may be the outlet of the screen flow area or the outlet of the packed perforation flow area. When calculating specifically, it is necessary to judge and select according to the specific sand control method.

11. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 1, characterized in that, In step 4, for a specific perforation sand control process, the flow efficiency or energy efficiency of the perforation subsystem, sand control subsystem, fracture subsystem, and reservoir subsystem are calculated based on steps 2 and 3. The flow efficiency of different subsystems is plotted and compared. The one with the lowest flow efficiency is the bottleneck link, i.e., the bottleneck system. The flow bottleneck coefficient R is the highest value of equivalent flow resistance R in the link of the flow system. FMAX The average value R of all systems FMIN The ratio: And judge the bottleneck degree of the total system: R ≤ the first preset value, the system has excellent fluidity, and the bottleneck link can be ignored; The first preset value < R ≤ the second preset value, the system has good fluidity, but there are bottleneck links; The second preset value < R ≤ the third preset value, the system has average fluidity, the bottleneck link is obvious, and it is recommended to take improvement measures; R > the third preset value, the system has poor fluidity, the bottleneck is serious, and improvement measures need to be taken; Among them, the second preset value is greater than the first preset value and less than the third preset value.

12. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 11, characterized in that, In step 5, according to the energy utilization efficiency evaluation indexes of each subsystem, a collaborative optimization design method for perforation-sand control parameters is proposed, which takes the balance of the flow resistance of each subsystem and the highest energy utilization efficiency of the total system as the principle, including the manual trial calculation optimization design method and the orthogonal combination optimization design method.

13. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 12, characterized in that, In step 5, the manual trial calculation optimization design method includes: 1a. Initially design the process parameters according to the conventional design method, and calculate the energy utilization evaluation indexes of each system and the total system indexes according to steps 2 and 3; 1b. Calculate the flow bottleneck coefficient R and judge the bottleneck situation; 1c. If R < the first preset value, then the current design result is a feasible and reasonable solution; otherwise, determine K. Fmin For the subsystem in question, adjust the design parameters of the subsystem to reduce its energy consumption until R < the first preset value is met. 1d. If it is difficult to achieve the condition that R < the first preset value, the condition is relaxed to R < the second preset value, but the total system liquid energy consumption density K is required. VZ >K VZc K VZ K represents the total system energy consumption density per ton of liquid. VZc It is the energy consumption density limit per ton of liquid required at the oilfield site; 1e. Repeat the above process until the optimal design is achieved.

14. The method for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs according to claim 12, characterized in that, In step 5, the orthogonal combination optimization design method includes: 5a. According to the selected perforation sand control process type, determine the number of target parameters Nx to be designed; 5b. Obtain the feasible values of all Nx target parameters; 5c. Determine the number of value levels Nv of the orthogonal design of each target parameter; 5d. Use the equal division method to obtain Nx factors corresponding to their respective Nv value levels; 5e. Consult and generate the Nx-Nv orthogonal design data table, that is, the orthogonal optimization design scheme; 5f. Use steps 2 and 3 to calculate the total system energy utilization indexes of all schemes; 5g. Take the energy consumption density per ton of fluid or the energy utilization efficiency as the evaluation index, and use the intuitive analysis method to obtain the optimal parameter combination.

15. A system for evaluating the energy efficiency and optimizing parameters of perforation sand control in loose sandstone reservoirs, characterized in that, The energy utilization efficiency evaluation and parameter optimization system for perforation sand control in loose sandstone reservoirs uses the energy utilization efficiency evaluation and parameter optimization method for perforation sand control in loose sandstone reservoirs described in any one of claims 1-14 to evaluate the energy utilization efficiency of each flow system and the total flow system after perforation completion and different combinations of sand control methods, as well as the collaborative optimization design of perforation sand control parameters.

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