Method for determining separated layer water injection rate and proportion between water injection well and injection-production well

Abstract

The invention discloses a water injection well and an injection-production well separated layer water injection rate and proportion determination method. Comprising the following steps: S1, acquiring data based on a modeling result and an oil reservoir numerical simulation result output by conventional rectangular grid or corner grid geological modeling software; s2, based on the data obtained in the step S1, the water injection rate of the water injection well in a single small layer and the total water injection rate of the water injection well in all perforation layers are determined, and the separated layer water injection rate and the separated layer water injection proportion of the water injection well are calculated; s3, on the basis of the data obtained in the step S1, injection and production well pairs with single-layer water injection effects are judged, and the separated layer water injection rate and the separated layer water injection proportion between injection and production wells are determined; and S4, based on the water absorption profile monitoring data, the layered water injection rate and the layered water injection proportion are determined. According to the method for determining the separated layer water injection rate and proportion of the water injection well and the injection-production wells, the separated layer water injection rate of the water injection well and the separated layer water injection rate of the injection-production wells can be rapidly and accurately evaluated, and a reliable basis is provided for reasonable formulation of an oilfield development scheme, adjustment of yield increasing measures and a working system and the like.

Description

Technical Field:

[0001] The present invention relates to the technical field of reservoir engineering, and particularly relates to a method for determining the stratified water injection volume and ratio between an injection well and a production-injection well. Background Art:

[0002] For the evaluation and calculation of the stratified water injection volume ratio of an injection well, there are currently mainly two methods: One is the direct testing method. By conducting an injection well water absorption profile test to obtain the water absorption volume of each single layer, and then dividing it by the total water injection volume at the wellhead, the stratified water injection volume ratio of the injection well can be obtained. Its advantage is that the data is true and reliable. The other is the numerical simulation calculation method. Through reservoir numerical simulation calculation, the stratified water injection volume and ratio of the injection well are obtained. For the evaluation and calculation of the stratified water injection volume ratio between a production-injection well, there are also two methods: One is the inter-well tracer test method. By injecting a tracer into a designated test sub-layer of the injection well and sampling and analyzing the tracer concentration of the produced fluid in the connected production well, the stratified water injection volume ratio between the production-injection well can be calculated. The other is the numerical simulation calculation method. Through streamline numerical simulation calculation, the stratified water injection volume and ratio between the production-injection well are obtained.

[0003] The above methods have the following deficiencies:

[0004] First, in a multi-layer sandstone oilfield, there are many oil layers developed vertically and the heterogeneity is serious. Using the water absorption profile test to obtain the water absorption volume of the injection well in different sub-layers or using the tracer test to obtain the water injection volume of the injection well in different injection-production directions in a certain sub-layer has a high cost and a long time consumption, and can only reflect the stratified and inter-well water injection situation at the current test time. Second, the traditional numerical simulation or streamline simulation has a long research cycle, and only the stratified water injection volume ratio information between the production-injection well is included in the streamline simulation results, and it is difficult to apply on a large scale. Summary of the Invention:

[0005] The present invention aims at the problems existing in the background art and provides a method for determining the stratified water injection volume and ratio between an injection well and a production-injection well. This method for determining the stratified water injection volume and ratio between an injection well and a production-injection well can quickly and accurately evaluate the stratified water injection volume of the injection well and the stratified water injection volume between the production-injection well, and provide a reliable basis for the reasonable formulation of the oilfield development plan, the adjustment of production increase measures and working systems, etc.

[0006] The present invention can achieve the solution of its problems through the following technical solutions: This method for determining the stratified water injection volume and ratio between an injection well and a production-injection well includes the following steps:

[0007] S1. Based on the modeling results output by a conventional rectangular grid or corner point grid geological modeling software and the reservoir numerical simulation results, obtain data;

[0008] S2. Based on the data obtained in step S1, determine the water injection volume of the water injection well in a single small layer and the total water injection volume of the water injection well in all perforated layers, and calculate the stratified water injection volume and stratified water injection ratio of the water injection well;

[0009] S3. Based on the data obtained in step S1, determine the injection-production well pairs with effective single-layer water injection, and determine the stratified water injection volume and stratified water injection ratio between the injection-production wells;

[0010] S4. Based on the water absorption profile monitoring data, determine the stratified water injection volume and stratified water injection ratio.

[0011] Further, step S1 obtains static attribute field data such as grid geometric information (grid vertex geometric coordinates), fault plane grid strike parameters, porosity of each grid, permeability in different directions, and effective thickness based on the modeling results output by conventional rectangular grid or corner point grid geological modeling software.

[0012] Based on the reservoir numerical simulation calculation results, obtain dynamic attribute field data such as grid flowing pressure, grid tracer concentration, well perforation grid coordinates (IJK values, and IJK values are natural numbers), and monthly water injection volume of injection wells.

[0013] Further, the method for step S2 to determine the water injection volume Q k of the water injection well in a single small layer is as follows:

[0014] Set the perforation grid coordinates of the water injection well in a certain simulation layer k as (Ix, Jy, Kz), and according to Darcy's law of seepage, the water injection volume of the water injection well in a single small layer can be obtained;

[0015] The formula of Darcy's law of seepage is:

[0016] V ki =(K k +K i )*(P k -P i ) / (2*μ*L i ) (1)

[0017] The formula for the water injection volume Q k of the water injection well in a single small layer is:

[0018]

[0019] In the formula: the perforation grid pressure is P k 、the permeability is K k ; the total number of effective grids adjacent to the perforation grid in the single-layer space and having a seepage connection relationship is m (m≥1), the corresponding grid pressures are Pi (i>1), the seepage cross-sectional area S ki 、flow velocity V ki, planar permeability K i ; μ is the fluid viscosity; L i is the distance between the center of the connected grid and the center of the perforated grid.

[0020] Furthermore, the effective grid is defined as the property field grid with porosity, permeability, and effective thickness all greater than 0; if the perforated grids of the water injection well and the oil production well in a single layer can be connected by the effective grid and the oil production well is within the swept range of the tracer in the single layer of the injection well, then this water injection well and oil production well will be defined as an effective injection-production direction or injection-production direction.

[0021] Furthermore, the method for determining the total water injection volume of the water injection well at all perforated horizons in step S2 is as follows:

[0022] Suppose the number of single layers with perforations in all sub-layers of the water injection well is n, and there is 1 effective perforated grid in each single layer. The water injection volume of each single layer can be obtained by applying formula (2), and the total water injection volume Q of all horizons can be obtained by accumulating the water injection volumes of single layers; the formula for the total water injection volume Q of all horizons is:

[0023]

[0024] Furthermore, the method for determining the water injection volume ratio of each layer of the water injection well in step S2 is as follows:

[0025] According to formula (3), the ratio of the water injection volume of a single layer of the water injection well to the total water injection volume of the whole well is given by the following formula:

[0026] α = Q k / Q * 100% (4)

[0027] The method for determining the water injection volume of each layer of the water injection well is as follows:

[0028] If the monthly water injection volume of the water injection well is A, then the monthly water injection volume A k of this well in a certain single layer is:

[0029] A k = A * α (5)

[0030] Combined with the property field and pressure field data of the simulation model, through the above formulas (4) and (5), the water injection volume and ratio of each layer of the water injection well can be calculated.

[0031] Furthermore, the method for determining the injection-production well pairs with effective water injection in a single layer in step S3 is as follows:

[0032] The injection well is perforated in a certain sub-layer. A tracer with a concentration of 1.0 that is completely soluble in water is continuously injected into the grid of this layer. The injection effect of the tracer is simulated using reservoir numerical simulation, and the simulation time is up to when the tracer concentration field is relatively stable. The area swept by the tracer in this layer at this time is defined as the injection swept area of the injection well in this layer. If there is a production well with perforation within this range, it is determined that the injection well and the production well are an effective injection-production well pair in this sub-layer.

[0033] Further, the method for determining the injection volume and ratio between the injection and production wells in step S3 is as follows:

[0034] According to the method for determining the injection-production well pairs with single-layer water injection response, it is assumed that there are n (n≥1) effective injection-production well pairs in a certain single layer, and each production well has 1 effective perforated grid in this layer;

[0035] Based on the grid coordinates of the perforated grid, the attribute information of the effective grids with connectivity relationships to this grid and its surrounding areas can be obtained. According to the water injection volume formula (2) of the injection well in a single sub-layer, the total inflow and outflow of each perforated grid can be calculated;

[0036] Let the concentration of the perforated grid of the injection well be c I , and the total inflow and outflow calculated according to formula (2) is Q I ;

[0037] Let the tracer concentration of the perforated grid of the production well obtained according to the numerical simulation calculation results be c j , and the total inflow and outflow corresponding to the perforated grid calculated according to formula (2) is Q j ;

[0038] Under the condition of injection-production balance (corresponding to the state where the tracer simulation calculates that the tracer concentration field is relatively stable and unchanged), the tracer concentration of each grid remains unchanged. Since the tracer is completely dissolved in water, the mass flow of the tracer represents the water inflow of the injection well. According to the tracer concentration and flow of the grid, the injection volume ratio α Ij between the injection and production wells in the direction is calculated by the following formula:

[0039]

[0040] Combined with the calculation result A k of formula (5), the injection volume A Ij between the injection and production wells in a single layer can be calculated as:

[0041] A Ij = A k * α Ij (7)

[0042] Further, a tracer with a concentration of 1 is set to be continuously injected into a single perforated layer of an injection well, and the tracer concentrations in each grid are obtained through simulation calculation of the tracer.

[0043] Further, the method for determining the layer-by-layer injection volume and the layer-by-layer injection ratio in step S4 based on the water absorption profile monitoring data is as follows:

[0044] For an injection well with water absorption profile monitoring data and an evaluation time point, each monitored layer section can be regarded as an independent injection well. Combining with the actual injection volume at the wellhead, the actual injection volume of the monitored layer section and its proportion in the total well injection volume can be obtained. The specific operations are as follows:

[0045] If the monitored layer section only contains 1 sub-layer, the injection volume and proportion of this sub-layer can be directly obtained, and the injection volumes and proportions in each injection-production direction of this sub-layer are calculated according to formula (6) and formula (7).

[0046] If the monitored layer section only contains multiple sub-layers, this monitored layer section is regarded as a virtual injection well, and the injection volumes and proportions of each sub-layer and injection-production direction within the monitored layer section are calculated according to formula (4), formula (5), formula (6) and formula (7).

[0047] The present invention may have the following beneficial effects compared with the above background technology:

[0048] Based on the grid tracer concentration simulated by the tracer, the present invention integrates the monitoring results of the water absorption profile, and according to theories such as Darcy's law and the principle of mass conservation, realizes the rapid and accurate calculation of the injection volume ratio of each layer of the injection well and the injection volume ratio of each layer between the injection and production wells. The relevant software compiled by using the method of the present invention can efficiently realize the splitting calculation of the injection volume of each layer of the injection well and can realize the evaluation of the injection volume and ratio of each layer between the injection and production wells.

[0049] Applying the technical achievements of the present invention can quantitatively characterize the flow direction and flow rate of the water injected into the injection well during the water injection development process, which has an important guiding role in identifying and controlling inefficient and ineffective circulation, and provides an important decision-making basis for improving the development effect of waterflooding oilfields and realizing precise development. Description of the drawings:

[0050] Attached Figure 1 is the flow chart of the method of the present invention;

[0051] Attached Figure 2 is the connection relationship diagram of a single-layer injection-production well pair of the present invention. Detailed implementation manners:

[0052] To make the objectives, technical solutions and advantages of the present invention clearer, the following will further describe the embodiments of the present invention in detail with reference to the drawings.

[0053] Such as Figure 1As shown in the figure, a method for determining the layered water injection volume and ratio between an injection well and a production well includes the following steps:

[0054] Step 1: Obtain data and known information according to the modeling results output by conventional rectangular grid or corner point grid geological modeling software and reservoir numerical simulation;

[0055] 1. According to the modeling results output by conventional rectangular grid or corner point grid geological modeling software, the modeling results include grid geometric information (grid vertex geometric coordinates) and fault plane grid strike parameters, as well as property field data such as porosity, permeability in different directions, and effective thickness of each grid.

[0056] According to the calculation results of reservoir numerical simulation, the flowing pressure value of each grid and the perforated grid coordinates (IJK values) of each well are obtained. The IJK values are natural numbers.

[0057] 2. Assume that a tracer with a concentration of 1 is continuously injected in a single perforated layer of the injection well, and the tracer concentration in each grid is obtained according to the tracer simulation calculation.

[0058] 3. An effective grid is defined as a property field grid with porosity, permeability, and effective thickness all greater than 0. In this solution, if the perforated grids of the injection well and the production well in a single layer can be connected by effective grids and are within the swept range of the tracer injected in a single layer of the injection well in the production well, then this injection well and production well will be defined as an effective injection-production direction or an injection-production direction.

[0059] Step 2: Calculation method for the layered water injection volume and layered water injection ratio of the injection well;

[0060] 1. Calculate the water injection volume Q of the injection well in a single sub-layer k

[0061] Assume that the perforated grid coordinates of the injection well (well name code: Inj) in a certain simulation layer (layer name: Layer_k) are (Ix, Jy, Kz), the pressure of this perforated grid is P k , the permeability is K k , the total number of effective grids adjacent to this perforated grid in the single-layer space and having a seepage connection relationship is m (m≥1), the corresponding grid pressures are Pi (i>1), the seepage cross-sectional area S corresponding to each connected grid and the perforated grid ki , the flow velocity V ki , the planar permeability K i , according to Darcy's seepage law, we can get:

[0062] V ki =(K k +K i )*(P k -P i ) / (2*μ*L i) (1)

[0063]

[0064] Where: V ki — Flow velocity between plane grids having a connection relationship with the perforation grid; K i — Grid plane permeability of the grid having a connection relationship with the perforation grid;

[0065] μ — Fluid viscosity; L i — Distance between the centers of the connected grids and the centers of the perforation grids.

[0066] 2. Calculate the total water injection volume of the water injection well at all perforated horizons

[0067] If the number of single layers with perforations in the water injection well among all sub-layers is n, and there is 1 effective perforation grid in each single layer, the water injection volume of each single layer can be obtained by applying formula (2), and the total water injection volume Q of all horizons can be obtained by accumulating the water injection volumes of single layers as follows:

[0068]

[0069] 3. Calculate the water injection volume ratio and water injection volume of each layer of the water injection well

[0070] According to formula (3), the ratio of the single-layer water injection volume of the water injection well to the total water injection volume of the well is given by the following formula:

[0071] α = Q k / Q * 100% (4)

[0072] If the monthly water injection volume of the water injection well is A, then the monthly water injection volume A k of the well in a certain single layer is:

[0073] A k = A * α (5)

[0074] Combined with the property field and pressure field data of the simulation model, through the above formulas, the water injection volume and ratio of each layer of the water injection well can be calculated.

[0075] Step 3. Calculation method for the water injection volume of each layer between the water injection well and the production well and the water injection ratio of each layer between the water injection well and the production well

[0076] 1. Determine the water injection-production well pairs affected by single-layer water injection

[0077] The injection well (with the well name code Inj) is perforated in a certain small layer Layer, and a tracer with a concentration of 1.0 that is completely soluble in water is continuously injected into the grid of this layer. The injection effect of the tracer is simulated using reservoir numerical simulation, and the simulation time ends when the tracer concentration field is relatively stable. The area swept by the tracer in this layer at this time is defined as the water injection swept area of the injection well in this layer. If there is a production well (with the well name code Prodj) and it is perforated within this range, then the injection well Inj and the production well Prodj are determined to be an effective injection-production well pair in this small layer Layer.

[0078] 2. Calculation of the water injection volume and ratio between the injection-production wells in different directions

[0079] According to the method of determining the effective injection-production well pairs for single-layer water injection in Step 1, if there are n (n≥1) effective injection-production well pairs in a certain single layer, and each production well has 1 effective perforated grid in this layer. Based on the grid coordinates of the perforated grid, the attribute information of the effective grids with connectivity relationships around this grid can be obtained, and the total inflow and outflow of each perforated grid can be calculated according to formula (2).

[0080] Denote the concentration of the perforated grid of the injection well as c I , and the total inflow and outflow calculated according to formula (2) is Q I ; Denote the tracer concentration of the perforated grid of the production well obtained according to the numerical simulation calculation result as c j , and the total inflow and outflow corresponding to the perforated grid calculated according to formula (2) is Q j .

[0081] Under the condition of injection-production balance (corresponding to the state where the tracer simulation calculates that the tracer concentration field remains relatively stable), the tracer concentration of each grid remains unchanged. Since the tracer is completely dissolved in water, then the mass flow rate of the tracer represents the water inflow of the injection well. According to the tracer concentration and flow rate of the grid, the water injection volume ratio α Ij between the injection-production wells in different directions is calculated by the following formula:

[0082]

[0083] Combined with the calculation result A k of formula (5), the water injection volume A Ij between the injection-production wells in a single layer can be calculated as:

[0084] A Ij = A k * α Ij (7)

[0085] Step 4. Calculation of the layered water injection volume and ratio based on the water absorption profile monitoring data

[0086] For injection wells with water absorption profile monitoring data and evaluation time points, each monitored interval can be regarded as an independent injection well. Combining with the actual injection volume at the wellhead, the actual injection volume of the monitored interval and its proportion in the total well injection volume can be obtained. The specific operation is as follows:

[0087] If the monitored interval contains only one sub-layer, the injection volume and proportion of this sub-layer can be directly obtained. The injection volume and proportion of each injection-production direction of this sub-layer are calculated according to formulas (6) and (7).

[0088] If the monitored interval contains multiple sub-layers, this monitored interval is regarded as a virtual injection well. The injection volume and proportion of each sub-layer and injection-production direction in the monitored interval are calculated according to formulas (4), (5), (6) and (7).

[0089] In summary, based on the geological modeling and numerical simulation results, combined with the monitoring data, the above formulas can be used to calculate the injection volume and proportion of each layer of the injection well and injection-production direction. By calculating the injection volume and proportion of each layer of the injection well, the water absorption capacity of each layer can be obtained; by calculating the injection volume and proportion between injection and production wells, the connectivity between injection and production wells can be analyzed, providing important parameters for realizing scientific injection-production dynamic regulation.

[0090] Example 1

[0091] 1. Method for calculating the injection volume and proportion of each layer of the injection well

[0092] 1.1 Application process of the method for calculating the injection volume and proportion of each layer of the injection well. Based on the calculation results data of the rectangular grid numerical simulation model established for an actual block, the pressure field extraction time is selected on August 31, 2012 (regarded as the grid flow pressure for the whole month of August). According to the well history record, the monthly injection volume for the whole month of August is 1,321.0 tons. An injection well INJ26 in this block is selected as the research object. This well has perforated grids in a total of 5 sub-layers (numbered 3, 7, 9, 12, 15) longitudinally. The corresponding IJK coordinates of the perforated grids are (26, 17, 3), (26, 17, 7), (26, 17, 9), (26, 17, 12), (26, 17, 15). There are four adjacent and connected effective grids around each of these perforated grids.

[0093] 1.2 Taking the perforated grid coordinates (26, 17, 3) as the object, the coordinates of the effective grids that are closely adjacent and have a connectivity relationship with it are obtained. There are a total of four grids, and their corresponding coordinates are (27, 17, 3), (25, 17, 3), (26, 18, 3), (26, 16, 3).

[0094] 1.3. Taking the grid coordinates closely adjacent to the perforation grid as the index, through the calculation results of the numerical simulation model, it is easy to extract grid attributes and geometric information such as the permeability, grid flowing pressure, grid center distance, and grid size of each grid, so as to calculate the flow cross-sectional area. Since what is sought is a proportional coefficient, it is only necessary that the physical units are consistent.

[0095] 1.4. Calculate the flow rates of the grids connected to the perforation grid of the perforation according to formulas (1) and (2), and sum up the flow rates to obtain the flow rates (Q3, Q7, Q9, Q12, Q15) of each perforation grid.

[0096] 1.5. Sum up the flow rates of all 5 perforation grids of the injection well INJ26 according to formula (3), and then apply formula (4) to calculate the proportion of the single-layer injection water volume of the injection well in the total well injection water volume (i.e., the stratified injection proportion).

[0097] 1.6. According to the proportion of the single-layer injection water volume in the total well injection volume obtained in the previous step, combined with the actual monthly injection water volume of this well being 1321.00 tons, and then according to formula (5), the theoretical calculated stratified injection volume for each layer per month can be calculated (assuming that the production is stable within a month). This provides important decision-making parameter information for formulating the block water injection dynamic regulation plan. The calculation results of the stratified injection water volume and proportion of the injection well INJ26 are shown in Table 1.

[0098] Table 1

[0099]

[0100] 2. Calculation method for the stratified injection water volume and proportion between injection and production wells

[0101] 2.1. Continuously inject a tracer with a concentration of 1.0 into the perforation grid (26,17,7) of the 7th layer of the injection well INJ26. According to the simulation calculation results of the tracer, tracers are found at the perforation grids (34,17,7) of the production well PROD59, (26,25,7) of the production well PROD60, (18,17,7) of the production well PROD62, and (26,9,7) of the production well PROD20 in the same layer, and the tracer concentration values are 0.13, 0.21, 0.34, and 0.32. Therefore, it is determined that the injection well INJ26 and the production wells PROD59, PROD60, PROD62, and PROD20 form injection-production well pairs with a displacement relationship. Therefore, the directional injection water volume and proportion between the injection well INJ26 and the above four production wells can be calculated.

[0102] 2.2. Extract relevant attribute values based on the perforation grids of injection wells PROD59, PROD60, PROD62, and PROD20 and the coordinates of their adjacent connected grids. Using steps similar to the calculation method for the layered injection volume and ratio of injection wells, calculate the total inflow and outflow of the perforation grids of each production well, namely Q1(200.06), Q2(201.81), Q3(317.45), and Q4(166.34) in Table 2.

[0103] 2.3. According to formula (6), combined with the tracer concentration values of the perforation grids obtained from tracer simulation, calculate the mass flow rate of the grid tracer and its proportional coefficient, that is, calculate the injection volume ratio in the injection-production well direction. Combining Table 1, it can be known that the layered injection volume of well INJ26 in the 7th layer is 312.81 tons. Then, applying formula (7), the layered injection volumes between the injection-production wells with injection-production connection relationships in the 7th layer are 54.126, 69.886, 154.596, and 34.202 tons respectively. The calculation results of the layered injection volumes and ratios between the injection-production wells of injection well INJ26 in the 7th layer are shown in Table 2.

[0104] Table 2

[0105]

[0106] According to the calculation method for the layered injection volumes and ratios between injection wells and injection-production wells, a software function module for verifying its application effect is compiled. The application includes the following steps:

[0107] S1. First, prepare a numerical simulation model that has completed history matching, extract the corresponding grid pressure field data information according to time, and obtain the monthly injection volume data of the injection well at this time.

[0108] S2. Secondly, apply the operation process of the software function module compiled by this method to calculate the distribution map of the connection relationships of each injection-production well pair in each single layer ( Figure 2 ) and the layered injection volume in the direction between each injection-production well pair in the single layer and the ratio of the layered injection volume in the direction to the single-layer injection volume of the injection well.

[0109] Those of ordinary skill in the art will realize that the embodiments described herein are for helping readers understand the implementation methods of the present invention and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those of ordinary skill in the art can make various other specific deformations and combinations that do not depart from the essence of the present invention based on the technical revelations disclosed in the present invention, and these deformations and combinations are still within the protection scope of the present invention.

Claims

1. A method for determining the layered water injection volume and ratio between an injection well and a production-injection well, characterized in that: It includes the following steps: S1. Obtain data based on the modeling results output by conventional rectangular grid or corner point grid geological modeling software and the reservoir numerical simulation results; S2. Based on the data obtained in step S1, determine the water injection volume of the water injection well in a single sub-layer and the total water injection volume of the water injection well in all perforated layers, and calculate the stratified water injection volume and stratified water injection ratio of the water injection well; S3. Based on the data obtained in step S1, determine the injection-production well pairs with effective single-layer water injection, and determine the stratified water injection volume and stratified water injection ratio between the injection-production wells; S4. Based on the water absorption profile monitoring data, determine the stratified water injection volume and stratified water injection ratio.

2. The method for determining the layered water injection volume and ratio between an injection well and a production well according to claim 1, wherein: In step S1, based on the modeling results output by conventional rectangular grid or corner point grid geological modeling software, obtain the static attribute field data such as grid geometric information, fault plane grid trend parameters, porosity of each grid, permeability in different directions, and effective thickness; Based on the reservoir numerical simulation calculation results, obtain the dynamic attribute field data such as grid flow pressure, grid tracer concentration, well perforation grid coordinates, and monthly water injection volume of the injection well.

3. The method for determining the stratified water injection volume and ratio between an injection well and a production-injection well according to claim 1, wherein: Step S2 determines the water injection volume Q of the water injection well in a single sub-layer k The method is as follows: Set the perforation grid coordinates of the water injection well in a certain simulation layer k as (Ix, Jy, Kz). According to Darcy's seepage law, the water injection volume of the water injection well in a single sub-layer can be obtained; The formula of Darcy's seepage law is: V ki = (K k + K i ) * (P k - P i ) / (2 * μ * L i ) (1) The water injection volume Q of the water injection well in a single small layer k is given by the formula: Wherein: the perforation grid pressure is P k , the permeability is K k ; the total number of effective grids adjacent to the perforation grid in the single-layer space and having a seepage connection relationship is m (m≥1), the corresponding grid pressures are Pi (i>1), and the seepage cross-sectional area S corresponding to each connected grid and the perforation grid ki , the flow velocity V ki , the planar permeability K i ; μ is the fluid viscosity; L i is the distance between the center of the connected grid and the center of the perforated grid.

4. According to the method for determining the stratified water injection volume and ratio between the water injection well and the injection-production well according to claim 3, it is characterized in that: The effective grid is defined as the attribute field grid with porosity, permeability, and effective thickness all greater than 0; If the perforation grids of the water injection well and the production well in a single layer can be connected by the effective grid and the production well is within the swept range of the tracer in the single layer of the injection well, then the water injection well and the production well will be defined as the effective injection-production direction or injection-production direction.

5. The method for determining the stratified water injection volume and ratio between an injection well and a water injection-production well according to claim 3, wherein: The method for determining the total water injection volume of the water injection well in all perforated layers in step S2 is: Set the number of single layers with perforations in all sub-layers of the water injection well as n, and there is 1 effective perforation grid in each single layer. The water injection volume of each single layer can be obtained by applying formula (2), and the total water injection volume Q of all layers can be obtained by accumulating the water injection volumes of all layers; the formula for the total water injection volume Q of all layers is:

6. The method for determining the layered water injection volume and ratio between an injection well and a production-injection well according to claim 5, wherein: The method for determining the stratified water injection ratio of the water injection well in step S2 is: According to formula (3), the ratio of the single-layer injection water volume of the water injection well to the total well water injection volume is given by the following formula: α = Q k / Q * 100% (4) The method for determining the stratified water injection volume of the water injection well is: If the monthly water injection volume of an injection well is A, then the monthly water injection volume A of this well in a certain single layer k is as follows: A k = A * α (5) Combined with the attribute field and pressure field data of the simulation model, through the above formulas (4) and (5), the stratified water injection volume and ratio of the water injection well can be calculated.

7. The method for determining the stratified water injection volume and ratio between the water injection well and the water injection-production well according to claim 1, characterized in that: The method for determining the injection-production well pairs with effective single-layer water injection in step S3 is: The water injection well perforates in a certain sub-layer Layer, and injects a tracer with a concentration of 1.0 and completely soluble in water continuously in the grid of this layer. Apply the tracer injection effect of the reservoir numerical simulation, and the simulation time ends until the tracer concentration field is relatively stable; take the swept area of the tracer in this layer at this time as the water injection swept range of the water injection well in this layer. If there is a production well and perforation within this range, then determine that the water injection well and the production well are effective injection-production well pairs in this sub-layer Layer.

8. The method for determining the layered water injection volume and ratio between an injection well and a production-injection well according to claim 7, characterized in that: The method for determining the directional water injection volume and ratio between the injection-production wells in step S3 is: According to the method for determining injection-production well pairs with single-layer water injection response, it is assumed that there are n (n≥1) effective injection-production well pairs in a certain single layer, and each production well has 1 effective perforation grid in this layer; According to the grid coordinates of the perforation grid, the attribute information of the effective grids with connectivity relationships in and around this grid can be obtained. According to the water injection volume formula (2) of the injection well in a single sub-layer, the total inflow and outflow of each perforation grid can be calculated; Let the concentration of the perforation grid of the water injection well be c I , and the total inflow and outflow calculated according to formula (2) is Q I ; Let the tracer concentration of the perforation grid of the production well obtained according to the numerical simulation calculation results be c j , and the total inflow and outflow corresponding to the perforation grid is calculated as Q according to formula (2) j ; Under the condition of injection-production balance, the tracer concentration in each grid remains unchanged. Since the tracer is completely dissolved in water, the mass flow rate of the tracer characterizes the water inflow of the injection well. According to the tracer concentration and flow rate in the grid, the injection water volume ratio α in the direction between the injection and production wells Ij is calculated by the following formula: Combined with the calculation result A of formula (5) k , the water injection volume A in the direction between the injection well and the production well of a single layer can be calculated Ij as follows: A Ij = A k * α Ij (7).

9. The method for determining the layered water injection volume and ratio between an injection well and a production-injection well according to claim 7, characterized in that: It is assumed that a tracer with a concentration of 1 is continuously injected in a single perforation layer of the injection well, and the tracer concentration in each grid is obtained through tracer simulation calculation.

10. The method for determining the stratified water injection volume and ratio between the water injection well and the injection-production well according to claim 1, wherein: Step S4, the method for determining the layered water injection volume and layered water injection ratio based on water absorption profile monitoring data includes: For injection wells with water absorption profile monitoring data and evaluation time points, each monitored interval can be regarded as an independent injection well. Combining with the actual wellhead water injection volume, the actual water injection volume of the monitored interval and its proportion in the total well water injection volume can be obtained. The specific operations are as follows: If the monitored interval only contains 1 sub-layer, the water injection volume and proportion of this sub-layer can be directly obtained, and the water injection volume and proportion in each injection-production direction of this sub-layer are calculated according to formula (6) and formula (7); If the monitored interval only contains multiple sub-layers, this monitored interval is regarded as 1 virtual injection well, and the water injection volume and proportion of each sub-layer and injection-production direction in the monitored interval are calculated according to formula (4), formula (5), formula (6) and formula (7).

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