A loose sandstone fracturing parameter optimization method considering proppant embedment

Abstract

The present application relates to a kind of loose sandstone optimization fracturing method considering proppant embedding, comprising: step S1: collecting and arranging the basic parameter information of target reservoir after fracturing;Step S2: based on rectangular reservoir model, considering its actual existence irregularity, necessary correction is carried out to initial proppant index;Step S3: obtain the optimized dimensionless production index and the corresponding dimensionless fracture conductivity;Step S4: calculate and optimize fracture length and fracture width;Step S5: corresponding adjustment is carried out to fracture width;Step S6: calculate the porosity of proppant in fracture and the permeability of fracture;Step S7: further optimization is obtained to be more in line with actual situation fracturing fracture length and width, to ensure the optimality and feasibility of fracturing design scheme.The present application not only improves the scientificity and accuracy of loose sandstone formation fracturing design, but also significantly improves the conductivity of fracture and the ultimate recovery of oil and gas well.

Description

Technical Field

[0001] This invention relates to an optimized fracturing method for loose sandstone that takes into account proppant embedding, belonging to the field of petroleum and natural gas engineering technology. Background Technology

[0002] Fracturing and packing, as a key completion strategy for loose sandstone reservoirs, is unique in that it can simultaneously enhance production and control sand. Loose sandstone reservoirs are generally characterized by weak cementation, high porosity and permeability, low strength, and high plasticity. Therefore, fracturing development requires creating short, wide fractures and packing them with a high sand ratio. This aims to guide reservoir fluids along the high-conductivity fracture zone to achieve a bilinear flow pattern. However, the high porosity and good permeability of loose sandstone make the fracture initiation and propagation mechanisms exceptionally complex. The actual conductivity of fractures during fracturing and packing is often affected by the proppant embedding effect, frequently deviating from the initial fracturing and packing design expectations. In the actual operation phase of fracturing, the closing pressure directly acts on the fractures formed in the loose sandstone reservoir, triggering varying degrees of proppant embedding. This reduces the actual width of the fractures. Furthermore, the rock debris generated during the embedding and compaction process can block pore channels, further reducing fracture conductivity. To address these challenges, new fracturing and filling optimization design methods are needed to consider the proppant embedding problem during the fracturing process of loose sandstone.

[0003] The proppant index method, proposed by Valko, Economides, and other scholars, aims to maximize production capacity by optimizing proppant fracture parameters. This method uses the proppant index to solve for the dimensionless production index and conductivity, thereby determining the optimal fracturing design parameters, and has been widely applied in the oil and gas industry. In recent years, many scholars have refined the proppant index method. For example, Jiang Tingxue further expanded the concept, using the maximum oil recovery index as the optimization objective, and explored the balance between fracture length and dimensionless fracture conductivity in low-permeability and ultra-low-permeability reservoirs, emphasizing the importance of synergistic optimization of both for improving post-fracturing production. Guo Jianchun, building on this foundation, combined economic considerations, non-Darcy flow effects, fracturing fluid damage, and other factors, constructing an optimal proppant index function model that incorporates the interrelationships between reservoir size, fracturing scale, and economic factors, with economic maximization as the guiding principle. This model provides a scientific basis for determining the optimal proppant index and fracture length in fracturing operations for specific gas reservoirs, ensuring the dual optimization of fracturing effect and economic benefits. However, the above studies mainly focused on hard formations with relatively high mechanical strength, with limited research on the proppant index method for loose sandstone reservoirs, and the impact of proppant embedding on conductivity was not considered.

[0004] When performing hydraulic fracturing in loose sandstone formations, the weak bonding between rock particles makes proppant embedding prone to occur during fracture placement. This means proppant particles may become partially or completely embedded in the rock matrix, reducing the actual fracture width and consequently affecting fracture conductivity and subsequent oil and gas production efficiency. Traditional fracturing design methods often overlook this critical factor, leading to deviations between design parameters and actual requirements, thus impacting fracturing effectiveness. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an optimized fracturing method for loose sandstone that considers proppant embedding. Based on this method, the invention takes into account the influence of proppant embedding on fracture width, thereby achieving optimization in the design of fracture length and width for fracturing loose sandstone.

[0006] Considering the effect of proppant embedding during fracturing of loose sandstone has the following advantages:

[0007] 1. It can improve the effectiveness of fracturing operations, enhance fracture stability, and help maintain the open state of fractures, thereby extending the flow path of oil and gas and improving oil and gas recovery. The type and particle size of proppant can be rationally selected according to the terrain, so that proppants with low embedding degree and low fragmentation rate can establish effective hydraulic fractures under high closure pressure conditions.

[0008] 2. It can optimize fracturing design schemes. Considering proppant embedding allows for more accurate calculation of fracture length and width, facilitating the design of fracturing schemes that better suit actual conditions and improving the success rate and efficiency of fracturing operations. By optimizing the amount and type of proppant used, construction costs can be reduced while ensuring fracturing effectiveness.

[0009] 3. Improve reservoir assessment, enhance the accuracy of reservoir permeability prediction, and improve reservoir stimulation effects. By optimizing the use of proppant and fracturing design schemes, reservoirs can be better stimulated, thereby improving reservoir permeability and oil and gas recovery.

[0010] Terminology Explanation:

[0011] The Kozeny-Carman theory is a theory that describes the relationship between rock permeability (K), porosity (ψ), and specific surface area (S). The Kozeny-Carman (KC) equation is the most well-known semi-empirical formula in the field of porous media seepage. For a long time, the KC equation and its generalized forms have been widely used to estimate the permeability of porous media. The KC equation is not only widely used in many fields such as underground seepage, oil and gas field development, chemical engineering, biochemistry, and electrochemistry to estimate and predict hydraulic conductivity, but it is also the fundamental basis for many seepage models. According to the KC equation, the permeability of porous media can be expressed as:

[0012]

[0013] The permeability of K porous media; ρ is the porosity of the porous medium; c and S are the Kozeny-Carman constant and the specific surface area of ​​the solid phase, respectively.

[0014] The technical solution provided by this invention to solve the above-mentioned technical problems is as follows:

[0015] An optimized fracturing method for loose sandstone considering proppant embedding includes:

[0016] Step S1: Collect and organize basic parameter information of the target reservoir after fracturing;

[0017] Step S2: Based on the rectangular reservoir model, considering its actual irregularities, make necessary corrections to the initial proppant index;

[0018] Step S3: Using the modified proppant index, perform mathematical calculations to obtain the optimal dimensionless production index and the corresponding dimensionless fracture conductivity.

[0019] Step S4: Based on the modified proppant index, further calculate and optimize the crack length and crack width;

[0020] Step S5: The proppant embedding has the greatest impact on the width of the fracturing fracture, which in turn affects the fracture's conductivity. Therefore, the proppant embedding has a significant impact on the optimization of the overall fracture parameters. During proppant placement, the actual embedding conditions in the reservoir rock should be considered, and the fracture width should be adjusted accordingly.

[0021] Step S6: Calculate the porosity of the proppant and the permeability of the crack based on the final width of the crack and the amount of proppant laid.

[0022] Step S7: Feed the fracture permeability calculated after considering proppant embedding into the proppant index optimization method for iterative calculation. Through this process, further optimize the fracture length and width to better reflect the actual situation, so as to ensure the optimality and feasibility of the fracturing design scheme.

[0023] According to a preferred embodiment of the present invention, the basic parameter information of the target reservoir after fracturing includes fracture length, loose sandstone reservoir length, proppant volume, loose sandstone reservoir volume, loose sandstone reservoir permeability, and reservoir width.

[0024] According to a preferred embodiment of the present invention, in step S2, based on the rectangular reservoir model and considering its actual irregularities, the initial proppant index is modified as necessary; including:

[0025] The formula for calculating the proppant index is:

[0026]

[0027] N p For the proppant index; k f For crack permeability, 10 -3 μm 2 k is the reservoir permeability, 10 -3 μm 2 V p For the volume of the proppant, m 3 V r Let m be the reservoir volume. 2 I represents the crack penetration ratio; x f Let x be the crack length, in meters (m); e y is the reservoir length, in meters; e W is the reservoir width, in meters; C is the fracture width, in meters. D The flow conductivity of the fracture is dimensionless.

[0028] The formula for calculating the modified proppant index is as follows:

[0029]

[0030] N′ p For the corrected propionate index; C A This is the equivalent coefficient.

[0031] According to a preferred embodiment of the present invention, in step S3, mathematical calculations are performed using the modified proppant index to obtain the optimized dimensionless production index and the corresponding dimensionless fracture conductivity; including:

[0032] The formula for calculating the optimal dimensionless production index is:

[0033]

[0034] in:

[0035] u = InC Do

[0036] Where: a, b, c, and d are parameters related to reservoir size;

[0037] The optimal formula for calculating the conductivity of dimensionless fractures is:

[0038]

[0039] C Do The conductivity of dimensionless fractures;

[0040] in:

[0041] y = y e / x e .

[0042] According to a preferred embodiment of the present invention, in step S4, based on the modified proppant index, the crack length and crack width are further calculated and optimized; including:

[0043] The optimal crack length is expressed as:

[0044]

[0045] x fo To optimize the crack length;

[0046] The optimal crack width is expressed as:

[0047]

[0048] W o To optimize the crack width.

[0049] According to a preferred embodiment of the present invention, in step S5, during the proppant placement process, the fracture width is adjusted accordingly, taking into account the actual situation of its embedding in the reservoir rock; including:

[0050] Step S51: Calculate the total number of proppant layers to be applied when the proppant is laid flat across the entire crack:

[0051]

[0052] Where N is the total number of proppant layers; L is the seam length (m); H is the seam height (m); R is the proppant radius (m); n is the number of layers; and X is a constant.

[0053] Step S52: The initial width of the crack is a measurement taken without considering any proppant intervention, i.e., the crack wall remains in its natural or initial state. The formula for calculating the initial width of the crack is:

[0054]

[0055] W f The initial width of the crack;

[0056] Step S53: The proppant is embedded in the coal seam under the action of in-situ stress. The proppant embedding depth is obtained according to Hertz's elastic contact theory. The formula for calculating the proppant embedding depth is:

[0057]

[0058] Where, d fν1 represents the proppant embedding depth; σ represents the pressure; ν1 represents the proppant Poisson's ratio; ν2 represents the coal-rock Poisson's ratio; E1 represents the proppant elastic modulus; E2 represents the coal-rock elastic modulus.

[0059] Step S54: Calculate the change in crack width after proppant placement: The formula for calculating the crack width after proppant placement, i.e., the adjusted crack width, is as follows:

[0060] W f0 =W f -2d f

[0061] Among them, W f0 The width of the crack after the proppant is embedded.

[0062] According to a preferred embodiment of the present invention, in step S6, the porosity of the proppant and the permeability of the crack are calculated based on the crack width after proppant embedding and the amount of proppant laid; including:

[0063] Step S61: Calculate the porosity of the proppant within the crack based on the crack width and the number of proppant layers after proppant embedding. The calculation formula is as follows:

[0064]

[0065] in, Porosity of the proppant within the crack; N is the total number of proppant layers; R is the proppant radius, in meters; W f0 The crack width after proppant embedding is in mm; L is the crack length in m; H is the crack height in m.

[0066] Step S62: Based on the Kozeny-Carman theory, the permeability of the fracture is expressed by the fracture porosity as follows:

[0067]

[0068] Where, k f D is the permeability of the fracture; r is the pore radius within the fracture, in meters; τ is the pore tortuosity.

[0069] According to a preferred embodiment of the present invention, step S7 is specifically implemented as follows:

[0070] Substitute the fracture permeability obtained in step S62 into step S4 to calculate the optimal fracture length and optimal fracture width, and repeat steps S4-S6 iteratively until the desired result is achieved. and Given the accuracy requirements, determine the optimal crack length and optimal crack width.

[0071] A computer device includes a memory and a processor, the memory storing a computer program, the processor executing the computer program to implement steps of an optimized fracturing method for loose sandstone that takes into account proppant embedding.

[0072] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of an optimized fracturing method for loose sandstone that takes into account proppant embedding.

[0073] The present invention has the following beneficial effects:

[0074] The optimized fracturing method of this invention utilizes the proppant index method, taking into account the proppant embedding situation. This not only improves the scientificity and accuracy of fracturing design in loose sandstone formations but also significantly enhances fracture conductivity and the ultimate recovery rate of oil and gas wells. Through refined management and dynamic adjustment, it effectively reduces the cost and risk of fracturing operations, providing strong support for the sustainable development of oil and gas resources. Attached Figure Description

[0075] Figure 1 This is a schematic diagram of the process of an optimized fracturing method for loose sandstone that takes into account proppant embedding according to the present invention;

[0076] Figure 2 This is a schematic diagram showing the comparison between the calculated flow-guiding capacity and the actual indoor test flow-guiding capacity of this invention;

[0077] Figure 3 A schematic diagram illustrating the relationship between the proppant index and the optimal seam length and width;

[0078] Figure 4 A schematic diagram showing the changes in fractures before and after proppant embedding in a loose sandstone reservoir;

[0079] Figure 5 This is a schematic diagram showing the cumulative yield over time with and without proppant embedding. Detailed Implementation

[0080] The present invention will be further defined below with reference to the accompanying drawings and embodiments, but is not limited thereto.

[0081] Example 1

[0082] An optimized fracturing method for loose sandstone considering proppant embedding, such as Figure 1 As shown, it includes:

[0083] Step S1: Collect and organize basic parameter information of the target reservoir after fracturing;

[0084] Step S2: Based on the rectangular reservoir model, considering its actual irregularities, make necessary corrections to the initial proppant index;

[0085] Step S3: Using the modified proppant index, perform mathematical calculations to obtain the optimal dimensionless production index and the corresponding dimensionless fracture conductivity.

[0086] Step S4: Based on the modified proppant index, further calculate and optimize the crack length and crack width;

[0087] Step S5: The proppant embedding has the greatest impact on the width of the fracturing fracture, which in turn affects the fracture's conductivity. Therefore, the proppant embedding has a significant impact on the optimization of the overall fracture parameters. During proppant placement, the actual embedding conditions in the reservoir rock should be considered, and the fracture width should be adjusted accordingly.

[0088] Step S6: Based on the final width of the crack and the amount of proppant laid, accurately calculate the porosity of the proppant and the permeability of the crack.

[0089] Step S7: Feed the fracture permeability calculated after considering proppant embedding into the proppant index optimization method for iterative calculation. Through this process, further optimize the fracture length and width to better reflect the actual situation, so as to ensure the optimality and feasibility of the fracturing design scheme.

[0090] Example 2

[0091] The difference between the optimized fracturing method for loose sandstone considering proppant embedding described in Example 1 and the method described in Example 1 is as follows:

[0092] Basic parameters of the target reservoir after fracturing include fracture length, length of loose sandstone reservoir, proppant volume, volume of loose sandstone reservoir, permeability of loose sandstone reservoir, and reservoir width.

[0093] In step S2, based on the rectangular reservoir model and considering its actual irregularities, the initial proppant index is modified as necessary; including:

[0094] The formula for calculating the proppant index is:

[0095]

[0096] N p For the proppant index; k f For crack permeability, 10 -3 μm 2 k is the reservoir permeability, 10 -3 μm 2 V p For the volume of the proppant, m 3 V r Let m be the reservoir volume. 2I represents the crack penetration ratio; x f Let x be the crack length, in meters (m); e y is the reservoir length, in meters; e W is the reservoir width, in meters; C is the fracture width, in meters. D The flow conductivity of the fracture is dimensionless.

[0097] When evaluating the propping performance of rectangular irregular reservoirs, the concept of a shape factor is introduced to more accurately correct and extend the original proppant index. This aims to reflect the impact of reservoir geometry heterogeneity on proppant effectiveness, thus deriving a proppant index specific to the characteristics of rectangular irregular reservoirs. The formula for calculating the corrected proppant index is as follows:

[0098]

[0099] N′ p C is the corrected proppant index; C is the shape factor of the irregular region, whose size is equal to the aspect ratio of the smallest bounding rectangle of the irregular region, and is dimensionless; C A This is the equivalent coefficient. Its value under certain shape factors is C. A The values ​​are shown in the table below.

[0100] Table 1

[0101]

[0102] In step S3, mathematical calculations are performed using the modified proppant index to obtain the optimized dimensionless production index and the corresponding dimensionless fracture conductivity; including:

[0103] The formula for calculating the optimal dimensionless production index is:

[0104]

[0105] in:

[0106] u = InC Do

[0107] Where: a, b, c, and d are parameters related to reservoir size; the values ​​of coefficients a, b, c, and d under different shape factors are shown in Table 2.

[0108] Table 2 The optimal formula for calculating the conductivity of dimensionless fractures is:

[0109]

[0110] C Do The conductivity of dimensionless fractures;

[0111] in:

[0112] y = y e / x e .

[0113] By comparing and analyzing the calculation results of the fracture conductivity model considering the proppant embedding effect with experimental data (e.g.) Figure 2 As shown in the figure, the two results are found to be in good agreement, thus verifying the accuracy of the model in predicting changes in fracture conductivity.

[0114] In step S4, based on the modified proppant index, the crack length and width are further calculated and optimized; including:

[0115] The optimal crack length is expressed as:

[0116]

[0117] x fo To optimize the crack length;

[0118] The optimal crack width is expressed as:

[0119]

[0120] W o To optimize the crack width.

[0121] In step S5, the proppant embedding has the greatest impact on the width of the fracturing fracture, which in turn affects the fracture's conductivity. Therefore, proppant embedding has a significant impact on the optimization of overall fracture parameters. A schematic diagram of fracture changes before and after proppant embedding in a loose sandstone reservoir is shown (e.g.,...). Figure 4 (As shown). During proppant placement, considering the actual situation of its embedding in the reservoir rock, the fracture width is adjusted accordingly; including:

[0122] Step S51: Calculate the total number of proppant layers to be applied when the proppant is laid flat across the entire crack:

[0123]

[0124] Where N is the total number of proppant layers; L is the seam length (m); H is the seam height (m); R is the proppant radius (m); n is the number of layers; and X is a constant.

[0125] Step S52: The initial width of the crack is a measurement taken without considering any proppant intervention, i.e., the crack wall remains in its natural or initial state. The formula for calculating the initial width of the crack is:

[0126]

[0127] W f The initial width of the crack;

[0128] Step S53: The proppant is embedded in the coal seam under the action of in-situ stress. The proppant embedding depth is obtained according to Hertz's elastic contact theory. The formula for calculating the proppant embedding depth is:

[0129]

[0130] Where, d f ν1 represents the proppant embedding depth; σ represents the pressure; ν1 represents the proppant Poisson's ratio; ν2 represents the coal-rock Poisson's ratio; E1 represents the proppant elastic modulus; E2 represents the coal-rock elastic modulus.

[0131] Step S54: Calculate the change in crack width after proppant placement: The formula for calculating the crack width after proppant placement, i.e., the adjusted crack width, is as follows:

[0132] W f0 =W f -2d f

[0133] Among them, W f0 The width of the crack after the proppant is embedded.

[0134] In step S6, based on the crack width after proppant embedding and the amount of proppant laid, the porosity of the proppant within the crack and the permeability of the crack are accurately calculated; including:

[0135] Step S61: Calculate the porosity of the proppant within the crack based on the crack width and the number of proppant layers after proppant embedding. The calculation formula is as follows:

[0136]

[0137] in, Porosity of the proppant within the crack; N is the total number of proppant layers; R is the proppant radius, in meters; W f0 The crack width after proppant embedding is in mm; L is the crack length in m; H is the crack height in m.

[0138] Step S62: Based on the Kozeny-Carman theory, the permeability of the fracture is expressed by the fracture porosity as follows:

[0139]

[0140] Where, k f D is the permeability of the fracture; r is the pore radius within the fracture, in meters; τ is the pore tortuosity.

[0141] The specific implementation process of step S7 includes:

[0142] Substitute the fracture permeability obtained in step S62 into step S4 to calculate the optimal fracture length and optimal fracture width, and repeat steps S4-S6 iteratively until the desired result is achieved. and Given the accuracy requirement of 2, determine the optimal crack length and optimal crack width.

[0143] and The optimal crack length is obtained from the iterative calculations of the nth and (n+1)th generations. and The optimal crack width is calculated for the nth and (n+1)th generation iterations; the accuracy of ε1 and ε2 is determined based on the actual site conditions.

[0144] Figure 3 A schematic diagram illustrating the relationship between the proppant index and the optimal seam length and width; Figure 5 This is a schematic diagram showing the cumulative yield over time with and without proppant embedding.

[0145] Example 3

[0146] A computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of an optimized fracturing method for loose sandstone considering proppant embedding, as described in Embodiment 1 or 2.

[0147] Example 4

[0148] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of an optimized fracturing method for loose sandstone considering proppant embedding as described in Embodiment 1 or 2.

Claims

1. An optimized fracturing method for loose sandstone considering proppant embedding, characterized in that, include: Step S1: Collect and organize basic parameter information of the target reservoir after fracturing; Step S2: Based on the rectangular reservoir model, considering its actual irregularities, make necessary corrections to the initial proppant index; Step S3: Using the modified proppant index, perform mathematical calculations to obtain the optimal dimensionless production index and the corresponding dimensionless fracture conductivity. Step S4: Based on the corrected proppant index and the optimized dimensionless fracture conductivity, further calculate and optimize the fracture length and fracture width. Step S5: During the proppant placement process, the fracture width is adjusted accordingly, taking into account the actual situation of its embedding in the reservoir rock. Step S6: Calculate the porosity of the proppant and the permeability of the crack based on the final width of the crack and the amount of proppant laid. Step S7: Feed the fracture permeability calculated after considering proppant embedding into the proppant index optimization method for iterative calculation. Through this process, further optimize the fracture length and width to better reflect the actual situation, so as to ensure the optimality and feasibility of the fracturing design scheme.

2. The optimized fracturing method for loose sandstone considering proppant embedding according to claim 1, characterized in that, The basic parameters of the target reservoir after fracturing include fracture length, length of loose sandstone reservoir, volume of proppant, volume of loose sandstone reservoir, permeability of loose sandstone reservoir, and reservoir width.

3. The optimized fracturing method for loose sandstone considering proppant embedding according to claim 1, characterized in that, In step S2, based on the rectangular reservoir model and considering its actual irregularities, the initial proppant index is modified as necessary; including: The formula for calculating the proppant index is: N p For the proppant index; k f For crack permeability, 10 -3 μm 2 k is the reservoir permeability, 10 -3 μm 2 V p For the volume of the proppant, m 3 V r Let m be the reservoir volume. 2 I represents the crack penetration ratio; x f Let x be the crack length, in meters (m); e y is the reservoir length, in meters; e W is the reservoir width, in meters; C is the fracture width, in meters. D The flow conductivity of the fracture is dimensionless. The formula for calculating the modified proppant index is as follows: N′ p For the corrected propionate index; C A This is the equivalent coefficient.

4. The optimized fracturing method for loose sandstone considering proppant embedding according to claim 3, characterized in that, In step S3, mathematical calculations are performed using the modified proppant index to obtain the optimized dimensionless production index and the corresponding dimensionless fracture conductivity; including: The formula for calculating the optimal dimensionless production index is: in: u=InC Do Where: a, b, c, and d are parameters related to reservoir size; The optimal formula for calculating the conductivity of dimensionless fractures is: C Do The conductivity of dimensionless fractures; in: y=y e / x e 。 5. The optimized fracturing method for loose sandstone considering proppant embedding according to claim 4, characterized in that, In step S4, based on the modified proppant index, the crack length and width are further calculated and optimized; including: The optimal crack length is expressed as: x fo To optimize the crack length; The optimal crack width is expressed as: W o To optimize the crack width.

6. The optimized fracturing method for loose sandstone considering proppant embedding according to claim 5, characterized in that, In step S5, during the proppant placement process, the fracture width is adjusted accordingly, taking into account the actual situation of its embedding in the reservoir rock. include: Step S51: Calculate the total number of proppant layers to be applied when the proppant is laid flat across the entire crack: Where N is the total number of proppant layers; L is the seam length (m); H is the seam height (m); R is the proppant radius (m); n is the number of layers; and X is a constant. Step S52: The initial width of the crack is a measurement taken without considering any proppant intervention, i.e., the crack wall remains in its natural or initial state. The formula for calculating the initial width of the crack is: W f The initial width of the crack; Step S53: The proppant is embedded in the coal seam under the action of in-situ stress. The proppant embedding depth is obtained according to Hertz's elastic contact theory. The formula for calculating the proppant embedding depth is: Where, d f ν1 is the proppant embedment depth; σ is the pressure; v1 is the proppant Poisson's ratio; ν2 is the coal-rock Poisson's ratio; E1 is the proppant elastic modulus; E2 is the coal-rock elastic modulus. Step S54: Calculate the change in crack width after proppant placement: The formula for calculating the crack width after proppant placement, i.e., the adjusted crack width, is as follows: W f0 =W f -2d f Among them, W f0 The width of the crack after the proppant is embedded.

7. The optimized fracturing method for loose sandstone considering proppant embedding according to claim 6, characterized in that, In step S6, based on the crack width after proppant embedding and the amount of proppant laid, the porosity of the proppant within the crack and the permeability of the crack are calculated; including: Step S61: Calculate the porosity of the proppant within the crack based on the crack width and the number of proppant layers after proppant embedding. The calculation formula is as follows: in, Porosity of the proppant within the crack; N is the total number of proppant layers; R is the proppant radius, in meters; W f0 The crack width after proppant embedding is in mm; L is the crack length in m; H is the crack height in m. Step S62: Based on the Kozeny-Carman theory, the permeability of the fracture is expressed by the fracture porosity as follows: Where, k f D is the permeability of the fracture; r is the pore radius within the fracture, in meters; τ is the pore tortuosity.

8. The optimized fracturing method for loose sandstone considering proppant embedding according to claim 7, characterized in that, The specific implementation process of step S7 includes: Substitute the fracture permeability obtained in step S62 into step S4 to calculate the optimal fracture length and optimal fracture width, and repeat steps S4-S6 iteratively until the desired result is achieved. and Given the accuracy requirements, determine the optimal crack length and optimal crack width.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of any one of the optimized fracturing methods for loose sandstone considering proppant embedding according to claims 1-8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of any one of the optimized fracturing methods for loose sandstone considering proppant embedding as described in claims 1-8.

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