Loose sandstone fracturing parameter optimization method considering proppant embedding

Abstract

The invention relates to a loose sandstone optimized fracturing method considering proppant embedding. The method comprises the steps that S1, basic parameter information of a fractured target reservoir is collected and arranged; s2, based on the rectangular reservoir model, considering the actual irregularity of the rectangular reservoir model, and performing necessary correction on the initial proppant index; s3, the optimal dimensionless production index and the dimensionless fracture flow conductivity corresponding to the optimal dimensionless production index are obtained; s4, calculating and optimizing the crack length and the crack width; s5, the crack width is correspondingly adjusted; s6, calculating the porosity of the propping agent in the crack and the permeability of the crack; and S7, further optimizing to obtain the fracture length and the fracture width which are more consistent with the actual condition, so as to ensure the optimality and the feasibility of a fracture design scheme. According to the method, the scientificity and the accuracy of fracturing design of the loose sandstone stratum are improved, and the flow conductivity of the cracks and the final recovery efficiency of an oil and gas well are remarkably improved.

Description

Technical Field

[0001] The invention relates to a loose sandstone optimized fracturing method considering proppant embedding, and belongs to the technical field of petroleum and natural gas engineering. Background Art

[0002] As a key completion strategy for loose sandstone reservoirs, the fracturing and filling process is unique in that it can take into account the dual effects of production increase and sand control. Loose sandstone reservoirs generally have the characteristics of weak cementation, high porosity and high permeability, low strength, and strong plasticity. Therefore, in the process of fracturing development, it is necessary to create short and wide fractures and fill them with sand at a high sand ratio. This is to guide the reservoir fluid to achieve a bilinear flow pattern along the high conductivity fracture area. However, the high porosity and good permeability of loose sandstone make the fracture initiation and expansion mechanism extremely complicated. The actual conductivity of the fractures in fracturing filling is often affected by the proppant embedding effect, which often deviates from the expectations of the initial fracturing and filling design. In the actual operation stage of the fracturing operation, the closing pressure directly acts on the fractures formed in the loose sandstone reservoir, causing different degrees of proppant embedding, which will reduce the actual width of the formed fractures. The detached rock debris produced by the loose sandstone during the embedding and compaction process may also block the pore channels, further reducing the fracture conductivity. To address the above challenges, new fracturing packing optimization design methods are needed to consider the proppant embedding problem during the fracturing process of unconsolidated sandstone.

[0003] The proppant index method proposed by Valko and Economides aims to maximize production capacity by optimizing propped fracture parameters. This method uses the proppant index to solve the dimensionless production index and conductivity, and then determines the optimal fracturing design parameters. It has been widely used in the oil and gas industry. In recent years, many scholars have made new improvements on the proppant index method. For example, Jiang Tingxue further expanded this concept, taking the maximum oil recovery index as the optimization target, and deeply explored the balance between fracture length and dimensionless fracture conductivity in low permeability and ultra-low permeability reservoirs, emphasizing the importance of coordinated optimization of the two for improving post-fracturing production. On this basis, Guo Jianchun combined economic considerations, non-Darcy flow effects, fracturing fluid damage and other multiple factors, and guided by economic maximization, constructed an optimal proppant index function model that includes the relationship between reservoir scale, fracturing scale and economic factors. This model provides a scientific basis for determining the optimal proppant index and fracture length in a specific gas reservoir during fracturing operations, ensuring the dual optimization of fracturing effect and economic benefits. However, the above studies mainly focus on hard formations with relatively high mechanical strength. There is little research on the proppant index method for loose sandstone reservoirs, and the effect of proppant embedding on conductivity is basically not considered.

[0004] When hydraulic fracturing is performed in loose sandstone formations, due to the weak bonding force between rock particles, proppant embedding is easy to occur during the laying process in the cracks, that is, the proppant particles are partially or completely embedded in the rock matrix, resulting in a reduction in the actual width of the cracks, which in turn affects the conductivity of the cracks and the subsequent oil and gas production efficiency. Traditional fracturing design methods often ignore this key factor, resulting in deviations between design parameters and actual needs, affecting the fracturing effect. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention provides a loose sandstone optimized fracturing method taking into account proppant embedding; on this basis, the present invention takes into account the influence of proppant embedding on the fracture width, and achieves optimization when designing the fracture length and fracture width of loose sandstone fracturing.

[0006] Considering the effect of proppant embedment during unconsolidated sandstone fracturing has the following benefits:

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

[0008] 2. It can optimize the fracturing design plan. After considering the embedding of proppant, the length and width of the crack can be calculated more accurately, which helps to design a fracturing plan that is more in line with the actual situation and improve the success rate and efficiency of fracturing operations. By optimizing the amount and type of proppant used, the construction cost can be reduced while ensuring the fracturing effect.

[0009] 3. Improve reservoir assessment, improve the accuracy of reservoir permeability prediction, and enhance the effect of reservoir transformation. By optimizing the use of proppants and fracturing design schemes, the reservoir can be better transformed and the permeability and oil and gas recovery rate of the reservoir can be improved.

[0010] Terminology explanation:

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

[0012]

[0013] K is the permeability of the porous medium; 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 the present invention to solve the above technical problems is:

[0015] A method for optimizing fracturing of unconsolidated sandstone considering proppant embedment, comprising:

[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 irregularity, necessary corrections are made to the initial proppant index;

[0018] Step S3: using the modified proppant index, mathematical calculation is performed to obtain the optimal dimensionless production index and the corresponding dimensionless fracture conductivity;

[0019] Step S4: further calculating and optimizing the fracture length and fracture width based on the modified proppant index;

[0020] Step S5: The biggest impact of proppant embedding is mainly on the width of the fracturing crack, which in turn affects the conductivity of the fracturing crack. Therefore, the embedding of proppant will have a great impact on the optimization of the entire fracture parameters. During the proppant laying process, the actual situation of its embedding in the reservoir rock is considered, and the crack width is adjusted accordingly;

[0021] Step S6: Calculate the porosity of the proppant in the fracture and the permeability of the fracture according to the final width of the fracture and the amount of proppant laid;

[0022] Step S7: The fracture permeability calculated after considering the embedding of proppant is fed back to the proppant index optimization method for iterative calculation. Through this process, the fracture length and width that are more in line with the actual situation are further optimized to ensure the optimality and feasibility of the fracturing design.

[0023] Preferably according to 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] Preferably, in step S2, based on the rectangular reservoir model, considering the actual irregularity, necessary corrections are made to the initial proppant index; including:

[0025] The proppant index is calculated as:

[0026]

[0027] N p is the proppant index; k f is the fracture permeability, 10 -3 μm 2 ; k is the reservoir permeability, 10 -3 μm 2 ; V p is the proppant volume, m 3 ; V r is the reservoir volume, m 2 ; I is the crack penetration ratio; x f is the crack length, m; x e is the reservoir length, m; y e is the reservoir width, m; W is the fracture width, m; C D is the fracture conductivity, dimensionless;

[0028] The modified proppant index is calculated as follows:

[0029]

[0030] N′ p is the modified proppant index; C A is the equivalent coefficient.

[0031] Preferably, in step S3, mathematical calculations are performed using the modified proppant index to obtain an optimized dimensionless production index and a corresponding dimensionless fracture conductivity; including:

[0032] The calculation formula of the optimized dimensionless production index is:

[0033]

[0034] in:

[0035] u=InC Do

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

[0037] The calculation formula for the optimized dimensionless fracture conductivity is:

[0038]

[0039] C Do is the dimensionless fracture conductivity;

[0040] in:

[0041] y=y e / x e .

[0042] Preferably, according to the present invention, in step S4, based on the modified proppant index, the length and width of the fracture are further calculated and optimized; comprising:

[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] Preferably, in step S5, during the proppant laying process, the crack width is adjusted accordingly taking into account the actual situation of the proppant being embedded in the reservoir rock; comprising:

[0050] Step S51: Calculate the total number of proppants laid when the proppant is laid flat across the entire fracture:

[0051]

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

[0053] Step S52: The initial width of the fracture is a measured value without considering any proppant intervention, that is, the fracture wall remains in a natural or initial state. The calculation formula for the initial width of the fracture is:

[0054]

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

[0056] Step S53: The proppant is embedded in the coal seam under the action of ground stress. The embedding depth of the proppant is obtained according to the Hertz elastic contact theory. The calculation formula of the embedding depth of the proppant is:

[0057]

[0058] Among them, d f is the embedding depth of the proppant; σ is the pressure; ν 1 is the Poisson's ratio of the proppant; ν2 E is the Poisson's ratio of coal rock; 1 is the elastic modulus of the proppant; E 2 is the elastic modulus of coal rock;

[0059] Step S54: Calculate the change in the crack width when the proppant is placed and embedded: The calculation formula for the crack width after the proppant is embedded, that is, the adjusted crack width, is:

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

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

[0062] Preferably, in step S6, the porosity of the proppant in the fracture and the permeability of the fracture are calculated according to the fracture width after the proppant is embedded and the number of proppant laid; comprising:

[0063] Step S61: Calculate the porosity of the proppant in the fracture according to the fracture width and the number of proppant placements after the proppant is embedded. The calculation formula is as follows:

[0064]

[0065] in, is the porosity of the proppant in the fracture; N is the total number of proppant paving; R is the proppant radius, m; W f0 is the crack width after proppant embedment, mm; L is the crack length, m; H is the crack height, m;

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

[0067]

[0068] Among them, k f is the permeability of the fracture, D; r is the pore radius in the fracture, m; τ is the pore tortuosity.

[0069] Preferably, according to the present invention, the specific implementation process of step S7 includes:

[0070] Substitute the crack permeability obtained in step S62 into step S4 to calculate the optimal crack length and the optimal crack width, and repeat steps S4 to S6 for iterative calculation until the optimal crack length and the optimal crack width are met. and Given the accuracy requirement, determine the optimal crack length and optimal crack width.

[0071] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, steps of a method for optimizing fracturing of loose sandstone taking proppant embedding into consideration are implemented.

[0072] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of a method for optimizing fracturing of unconsolidated sandstones with proppant embedment.

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

[0074] The optimized fracturing method of the present invention utilizes the proppant index method to take into account the embedding of proppant, which not only improves the scientificity and accuracy of fracturing design in loose sandstone formations, but also significantly improves the conductivity of fractures and the ultimate recovery rate of oil and gas wells. Through refined management and dynamic adjustment, the cost and risk of fracturing operations are effectively reduced, providing strong support for the sustainable development of oil and gas resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Figure 1 A schematic diagram of a process of optimizing fracturing method for loose sandstone considering proppant embedding according to the present invention;

[0076] Figure 2 This is a schematic diagram showing the comparative relationship between the calculated flow conductivity of the present invention and the actual flow conductivity of indoor tests;

[0077] Figure 3 Schematic diagram of the relationship between the proppant index and the optimal fracture length and width;

[0078] Figure 4 Schematic diagram of crack changes before and after proppant embedding in loose sandstone reservoir;

[0079] Figure 5 Schematic diagram of the cumulative production variation with time with and without considering proppant embedding. DETAILED DESCRIPTION

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

[0081] Example 1

[0082] An optimized fracturing method for unconsolidated sandstone considering proppant embedment, such as Figure 1 As shown, including:

[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 irregularity, necessary corrections are made to the initial proppant index;

[0085] Step S3: using the modified proppant index, mathematical calculation is performed to obtain the optimal dimensionless production index and the corresponding dimensionless fracture conductivity;

[0086] Step S4: further calculating and optimizing the fracture length and fracture width based on the modified proppant index;

[0087] Step S5: The biggest impact of proppant embedding is mainly on the width of the fracturing crack, which in turn affects the conductivity of the fracturing crack. Therefore, the embedding of proppant will have a great impact on the optimization of the entire fracture parameters. During the proppant laying process, the actual situation of its embedding in the reservoir rock is considered, and the crack width is adjusted accordingly;

[0088] Step S6: accurately calculating the porosity of the proppant in the fracture and the permeability of the fracture according to the final width of the fracture and the amount of proppant laid;

[0089] Step S7: The fracture permeability calculated after considering the embedding of proppant is fed back to the proppant index optimization method for iterative calculation. Through this process, the fracture length and width that are more in line with the actual situation are further optimized to ensure the optimality and feasibility of the fracturing design.

[0090] Example 2

[0091] The optimized fracturing method for loose sandstone considering proppant embedding described in Example 1 is different in that:

[0092] 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.

[0093] In step S2, based on the rectangular reservoir model, considering its actual irregularity, necessary corrections are made to the initial proppant index; including:

[0094] The proppant index is calculated as:

[0095]

[0096] N p is the proppant index; k f is the fracture permeability, 10 -3 μm 2 ; k is the reservoir permeability, 10 -3 μm 2 ; V p is the proppant volume, m 3 ; V r is the reservoir volume, m 2; I is the crack penetration ratio; x f is the crack length, m; x e is the reservoir length, m; y e is the reservoir width, m; W is the fracture width, m; C D is the fracture conductivity, dimensionless;

[0097] When evaluating the proppant performance of rectangular irregular reservoirs, the concept of shape factor is introduced to more accurately modify and expand the original proppant index. It aims to reflect the impact of reservoir geometric heterogeneity on proppant performance, thereby obtaining a proppant index for rectangular irregular reservoir characteristics. The calculation formula of the modified proppant index is as follows:

[0098]

[0099] N′ p is the modified proppant index; C is the shape factor of the irregular area, which is equal to the aspect ratio of the smallest circumscribed rectangle of the irregular area and is dimensionless; C A is the equivalent coefficient. Under some shape factors, C A The values ​​are shown in the following table.

[0100] Table 1

[0101]

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

[0103] The calculation formula of the optimized dimensionless production index is:

[0104]

[0105] in:

[0106] u=InC Do

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

[0108] Table 2 The calculation formula for the optimized dimensionless fracture conductivity is:

[0109]

[0110] C Do is the dimensionless fracture conductivity;

[0111] in:

[0112] y=y e / x e .

[0113] By comparing the fracture conductivity model calculation results considering the proppant embedding effect with the experimental data (such as Figure 2 It was found that the two were consistent with each other, thus verifying the accuracy of the model in predicting the changes in fracture conductivity.

[0114] In step S4, based on the modified proppant index, the length and width of the fracture 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 biggest impact of proppant embedding is mainly on the width of the fracturing crack, which in turn affects the conductivity of the fracturing crack. Therefore, the embedding of proppant will have a great impact on the optimization of the entire fracture parameters. Schematic diagram of fracture changes before and after proppant embedding in loose sandstone reservoir (see Figure 2) Figure 4 During the proppant placement process, the actual situation of the proppant embedded in the reservoir rock is taken into consideration and the crack width is adjusted accordingly; including:

[0122] Step S51: Calculate the total number of proppants laid when the proppant is laid flat across the entire fracture:

[0123]

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

[0125] Step S52: The initial width of the fracture is a measured value without considering any proppant intervention, that is, the fracture wall remains in a natural or initial state. The calculation formula for the initial width of the fracture is:

[0126]

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

[0128] Step S53: The proppant is embedded in the coal seam under the action of ground stress. The embedding depth of the proppant is obtained according to the Hertz elastic contact theory. The calculation formula of the embedding depth of the proppant is:

[0129]

[0130] Among them, d f is the embedding depth of the proppant; σ is the pressure; ν 1 is the Poisson's ratio of the proppant; ν 2 E is the Poisson's ratio of coal rock; 1 is the elastic modulus of the proppant; E 2 is the elastic modulus of coal rock;

[0131] Step S54: Calculate the change in the crack width when the proppant is placed and embedded: The calculation formula for the crack width after the proppant is embedded, that is, the adjusted crack width, is:

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

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

[0134] In step S6, the porosity of the proppant in the fracture and the permeability of the fracture are accurately calculated according to the fracture width after the proppant is embedded and the number of proppant laid; including:

[0135] Step S61: Calculate the porosity of the proppant in the fracture according to the fracture width and the number of proppant placements after the proppant is embedded. The calculation formula is as follows:

[0136]

[0137] in, is the porosity of the proppant in the fracture; N is the total number of proppant paving; R is the proppant radius, m; W f0 is the crack width after proppant embedment, mm; L is the crack length, m; H is the crack height, m;

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

[0139]

[0140] Among them, k fis the permeability of the fracture, D; r is the pore radius in the fracture, m; τ is the pore tortuosity.

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

[0142] Substitute the crack permeability obtained in step S62 into step S4 to calculate the optimal crack length and the optimal crack width, and repeat steps S4 to S6 for iterative calculation until the optimal crack length and the optimal crack width are met. and 2 Given the accuracy requirement, determine the optimal crack length and optimal crack width.

[0143] and The optimal crack length obtained by iterative calculation for the nth and n+1th generations; and is the optimal crack width obtained by iterative calculation of the nth and n+1th generations; ε 1 , ε 2 The accuracy is determined according to the actual situation on site.

[0144] Figure 3 Schematic diagram of the relationship between the proppant index and the optimal fracture length and width; Figure 5 Schematic diagram of the cumulative production variation with time with and without considering proppant embedding.

[0145] Example 3

[0146] A computer device includes a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of an optimized fracturing method for loose sandstone taking into account proppant embedding as described in Example 1 or 2 are implemented.

[0147] Example 4

[0148] A computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of a loose sandstone optimized fracturing method taking into account proppant embedding as described in Example 1 or 2.

Claims

1. A method for optimizing fracturing of loose sandstones taking proppant embedding into consideration, 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 irregularity, necessary corrections are made to the initial proppant index; Step S3: using the modified proppant index, mathematical calculation is performed to obtain the optimal dimensionless production index and the corresponding dimensionless fracture conductivity; Step S4: further calculating and optimizing the fracture length and fracture width based on the modified proppant index; Step S5: During the proppant laying process, the actual situation of the proppant embedded in the reservoir rock is taken into consideration and the crack width is adjusted accordingly; Step S6: Calculate the porosity of the proppant in the fracture and the permeability of the fracture according to the final width of the fracture and the amount of proppant laid; Step S7: The fracture permeability calculated after considering the embedding of proppant is fed back to the proppant index optimization method for iterative calculation. Through this process, the fracture length and width that are more in line with the actual situation are further optimized to ensure the optimality and feasibility of the fracturing design.

2. The method for optimizing fracturing of loose sandstone considering proppant embedding according to claim 1, characterized in that: 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.

3. The method for optimizing fracturing of loose sandstone considering proppant embedding according to claim 1, characterized in that: In step S2, based on the rectangular reservoir model, considering its actual irregularity, necessary corrections are made to the initial proppant index; including: The proppant index is calculated as: N p is the proppant index; k f is the fracture permeability, 10 -3 μm 2 ; k is the reservoir permeability, 10 -3 μm 2 ; V p is the proppant volume, m 3 ; V r is the reservoir volume, m 2 ; I is the crack penetration ratio; x f is the crack length, m; x e is the reservoir length, m; y e is the reservoir width, m; W is the fracture width, m; C D is the fracture conductivity, dimensionless; The modified proppant index is calculated as follows: N′ p is the modified proppant index; C A is the equivalent coefficient.

4. The method for optimizing fracturing of loose sandstone considering proppant embedding according to claim 1, characterized in that: In step S3, mathematical calculations are performed using the modified proppant index to obtain the optimal dimensionless production index and the corresponding dimensionless fracture conductivity; including: The calculation formula of the optimized dimensionless production index is: in: u=InC Do Among them: a, b, c, d are parameters related to reservoir size; The calculation formula for the optimized dimensionless fracture conductivity is: C Do is the dimensionless fracture conductivity; in: y=y e / x e 。 5. The method for optimizing fracturing of loose sandstone considering proppant embedding according to claim 1, characterized in that: In step S4, based on the modified proppant index, the length and width of the fracture 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 method for optimizing fracturing of loose sandstone considering proppant embedment according to claim 1, characterized in that: In step S5, during the proppant laying process, the crack width is adjusted accordingly considering the actual situation of the proppant embedded in the reservoir rock; include: Step S51: Calculate the total number of proppants laid when the proppant is laid flat across the entire fracture: Where N is the total number of proppant paving; L is the seam length, m; H is the seam height, m; R is the proppant radius, m; n is the number of paving layers; X is a constant; Step S52: The initial width of the fracture is a measured value without considering any proppant intervention, that is, the fracture wall remains in a natural or initial state. The calculation formula for the initial width of the fracture is: W f is the initial width of the crack; Step S53: The proppant is embedded in the coal seam under the action of ground stress. The embedding depth of the proppant is obtained according to the Hertz elastic contact theory. The calculation formula of the embedding depth of the proppant is: Among them, d f is the embedding depth of proppant; σ is the pressure; ν1 is the Poisson's ratio of proppant; ν2 is the Poisson's ratio of coal rock; E1 is the elastic modulus of proppant; E2 is the elastic modulus of coal rock; Step S54: Calculate the change in the crack width when the proppant is placed and embedded: The calculation formula for the crack width after the proppant is embedded, that is, the adjusted crack width, is: W f0 =W f -2d f Among them, W f0 It is the width of the crack after proppant is embedded.

7. A loose sandstone optimized fracturing method considering proppant embedding according to any one of claims 1 to 6, characterized in that: In step S6, the porosity of the proppant in the fracture and the permeability of the fracture are calculated according to the fracture width after the proppant is embedded and the number of proppant laid; including: Step S61: Calculate the porosity of the proppant in the fracture according to the fracture width and the number of proppant placements after the proppant is embedded. The calculation formula is as follows: in, is the porosity of the proppant in the fracture; N is the total number of proppant paving; R is the proppant radius, m; W f0 is the crack width after proppant embedment, mm; L is the crack length, m; H is the crack height, m; Step S62: Based on the Kozeny-Carman theory, the permeability of the fracture is expressed by the fracture porosity as: Among them, k f is the permeability of the fracture, D; r is the pore radius in the fracture, m; τ is the pore tortuosity.

8. The method for optimizing fracturing of loose sandstones taking proppant embedding into consideration according to claim 7, characterized in that: The specific implementation process of step S7 includes: Substitute the crack permeability obtained in step S62 into step S4 to calculate the optimal crack length and the optimal crack width, and repeat steps S4 to S6 for iterative calculation until the optimal crack length and the optimal crack width are met. and Given the accuracy requirement, 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, wherein: When the processor executes the computer program, the steps of any one of claims 1 to 8 of the method for optimizing fracturing of loose sandstone taking proppant embedding into consideration are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of any one of claims 1 to 8 of a method for optimizing fracturing of loose sandstone taking proppant embedding into consideration are implemented.

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