Multi-layer commingling production yield splitting method

Abstract

The invention relates to the technical field of oil development, in particular to a multi-layer commingling production yield splitting method which comprises the following steps: carrying out a multi-tube parallel core physical experiment to determine main control factors of yield change of a multi-layer commingling production well; constructing a multi-layer commingling theory splitting model by taking the main control factors as basic parameters, and introducing correction of components to front and rear edge moving speeds to improve the multi-layer commingling theory splitting model; and establishing a multi-layer commingling production yield splitting method based on component correction, and correcting the improved theoretical model by using a component change rule. According to the method, the multi-layer commingling theory splitting model is constructed on the basis of determining the main control factors, the model is corrected by using the component change rule, the required data volume is small, and the splitting precision is high and stable.

Description

Technical Field

[0001] The present invention relates to the technical field of petroleum development, and more specifically, to a multi-layer combined production splitting method. Background Art

[0002] When developing gas fields using multi-layer commingled wells, the large differences in the composition, physical properties and water bodies of each layer lead to prominent interlayer interference conflicts, which affects the understanding of the production degree of each layer and restricts the potential of the remaining gas in the gas field.

[0003] At present, there are two main methods for production splitting: geological parameter method, which mainly includes effective thickness method and formation coefficient method. This method considers a single factor, only static parameters, and has a large error; the production splitting method based on mutation theory is developed by using mathematical topology to establish a multi-layer combined production well production splitting method using mutation theory. This method considers multiple groups of factors, including the depth of gas layer, gas layer thickness, porosity, gas saturation, sandstone content, rock density, sedimentary microfacies in geological factors, and permeability, interlayer interference, formation pressure, etc. in dynamic factors, totaling more than ten factors. Although the accuracy has been greatly improved compared with the geological parameter method, the splitting result is always a constant value, and it is impossible to describe the change of gas production contribution of small layers in gas wells with production time. Moreover, as the production time progresses, the output ratio of each layer is constantly changing due to the influence of production allocation adjustment, well shut-in testing, and different output levels of each layer.

[0004] The prior art discloses a method and system for intelligent production splitting of multi-layer commingled gas wells, the method comprising: determining the main controlling factors of production splitting of multi-layer commingled gas wells; constructing a machine learning model; training the machine learning model based on the main controlling factors to obtain a trained machine learning model; performing layered production splitting prediction based on the trained machine learning model to obtain the production splitting coefficients and production of each layer in the multi-layer commingled gas well. This solution uses a machine learning method, which requires a large amount of data, and the training results have poor prediction effects on fluctuations and poor adaptability. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the production splitting methods in the prior art, which require a large amount of data and have poor adaptability, and to provide a multi-layer combined production splitting method, which corrects the multi-layer combined production splitting model based on components, reduces the required data volume, improves the splitting accuracy and its stability, and has strong adaptability.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] A multi-layer commingled production splitting method is provided, comprising the following steps:

[0008] S1: Conduct multi-tube parallel core physical experiments to clarify the main controlling factors of production changes in multi-layer commingled production wells;

[0009] S2: A multi-layer commingled mining theoretical splitting model is constructed based on the main controlling factors as the basic parameters, and the multi-layer commingled mining theoretical splitting model is improved by introducing the correction of the moving speed of the leading and trailing edges by components;

[0010] S3: Establish a multi-layer commingled production splitting method based on component correction, and use the component change law to correct the improved theoretical model.

[0011] The multi-layer commingled production splitting method of the present invention constructs a multi-layer commingled production theoretical splitting model based on the determination of the main controlling factors, and uses the component change law to correct the model. It requires a small amount of data and has high and stable splitting accuracy.

[0012] Preferably, in step S1, the device for carrying out the multi-tube parallel core physical experiment includes a formation water sampler, a crude oil sampler, a gas sampler, a first double-cylinder displacement pump, a second double-cylinder displacement pump, a third double-cylinder displacement pump, a formation water intermediate container, a crude oil intermediate container, a gas intermediate container, a pressure sensor, a confining pressure pump, a six-way valve, a back pressure valve, and a flow controller, and a first core clamp, a second core clamp, and a third core clamp connected in parallel through the six-way valve, wherein the first core clamp, the second core clamp, and the third core clamp are respectively connected to the confining pressure pump, and the first double The cylinder displacement pump is connected to the first core clamp through the formation water intermediate container, and the formation water sampler is connected in parallel with the formation water intermediate container. The second double-cylinder displacement pump is connected to the second core clamp through the crude oil intermediate container, and the crude oil sampler is connected in parallel with the crude oil intermediate container. The third double-cylinder displacement pump is connected to the third core clamp through the gas intermediate container, and the gas sampler is connected in parallel with the gas intermediate container. The back pressure valve is arranged between the six-way valve and the flow control meter, and the pressure sensors are respectively arranged in the core clamps.

[0013] Preferably, in step S1, by changing the core permeability, core length and displacement pressure, the influence of layer physical property differences, reserves, pressure difference and water invasion factors on production splitting during multi-layer combined production is simulated to determine the main controlling factors of core-scale gas production contribution.

[0014] Preferably, in step S1, for the single-tube experiment of constant pressure difference water drive gas, the main controlling factors include permeability and CO2 content; for the parallel depletion experiment, the main controlling factors include permeability, fluid flow rate, porosity and comprehensive compression coefficient; for the parallel fixed inlet flow rate and fixed outlet pressure test, the main controlling factors include injection rate; for the parallel fixed inlet pressure and fixed outlet flow rate test, the main controlling factors include permeability, injection pressure and total production rate.

[0015] Preferably, in step S2, the process of establishing the multi-layer commingled production theoretical splitting model is as follows:

[0016] Assumptions: circular formation, horizontal, homogeneous, unequal thickness, impermeable layers between upper and lower layers, one production well in the center of the circular formation, producing gas at a constant flow rate; the reservoir space contains bound water saturation, and the dissolution of CO2 in the gas component in water is considered, the diffusion of water phase in gas is not considered, and the physical and chemical reactions of rocks are not considered; the edge water energy is sufficient, the fluid is compressible, the development process is isothermal, the flow follows Darcy's law, and the influence of capillary force and gravity are ignored; the physical stage studied is before water appears in the production well, that is, the water drive gas only production stage;

[0017] A dimensionless mathematical model is established, and the radial coordinate seepage partial differential equation of the vertical well in the kth zone of the jth layer and its initial conditions, inner boundary adjustment, outer boundary conditions, and connection conditions are as follows:

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028] in:

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046] In the formula, It means to find partial derivatives of parameters; represents dimensionless pressure; r D represents dimensionless distance; ω jk represents the dimensionless storage capacity coefficient of the kth zone of the jth layer; x jk represents the interlayer flow coefficient ratio of the jth layer and the kth zone; t D represents dimensionless time; represents the dimensionless radius of the kth zone of the jth layer; Represents dimensionless effective well diameter; q jD represents the dimensionless output of the jth layer; represents the dimensionless bottom hole pressure; represents the original dimensionless pressure; r wejD represents the dimensionless effective well radius of the jth layer; r ejD represents the dimensionless outer boundary distance of the jth layer; λ j represents the partition flow ratio; r represents the radial cylinder radius; h t Indicates the total storage thickness; h j represents the reservoir thickness of the jth layer; Indicates the average interlayer flow rate of the thickness clamp; K j,1 represents the formation permeability of the first zone of the jth layer; K j,2 represents the formation permeability of the second zone of the jth layer; K j,3 represents the formation permeability of zone 3 in layer j; represents the gas phase permeability in the first zone of the jth layer; represents the gas phase permeability in the second zone of the jth layer; represents the relative water permeability of zone 2 in layer j; represents the relative water permeability of the third zone of the jth layer; μ g,j,1 represents the gas viscosity of the first zone of the jth layer; μ g,j,2 represents the gas viscosity of the second zone of the jth layer; μ g,j,3 represents the gas viscosity of the third zone of the jth layer; μ w,j,2 represents the water viscosity in the second zone of the jth layer; μ w,j,3 represents the water viscosity in zone 3 of layer j; Indicates gas-water two-phase drive in zone 2; Φ j,1 represents the porosity of the first zone of the jth layer; Φ j,2 represents the porosity of the second zone of the jth layer; Φ j,3 represents the porosity of the third zone of the jth layer; C tj,1 represents the comprehensive compression coefficient of the first zone of the jth layer; C tj,2 represents the comprehensive compression coefficient of the second zone of the jth layer; C tj,3 represents the comprehensive compression factor of the third zone of the jth layer; Indicates the reference pressure; represents the formation pressure in zone 1 of layer j; represents the formation pressure in zone 2 of layer j; represents the formation pressure in the third zone of the jth layer; (ΦC t ) a represents the average storage coefficient of the layers weighted by thickness; q represents the bottom hole production of the gas well; B represents the average volume coefficient of gas in the near-well gas zone of each layer; B j represents the average volume coefficient of the j-th layer of gas; q jD represents the dimensionless stratified output in real space; q j represents the output of the jth layer; B j represents the gas volume coefficient of the jth layer; S j represents the skin factor of the jth layer; r w represents the true well radius; indicates; r ej Represents the outer boundary radius of the jth layer; r ejD Represents the dimensionless outer boundary radius of the jth layer; wherein, the first zone I of the first layer, the first zone IV of the second layer, and the first zone VII of the third layer represent the gas zone of the edge water constant pressure boundary; the second zone II of the first layer, the second zone V of the second layer, and the second zone VIII of the third layer represent the gas-water mixed zone of the edge water constant pressure boundary; the third zone III of the first layer, the third zone VI of the second layer, and the third zone IX of the third layer represent the water zone of the edge water constant pressure boundary.

[0047] Preferably, the solution of the dimensionless mathematical model needs to be transformed into the Laplace space first, and the general solution containing the Bessel function is obtained:

[0048]

[0049] In the formula, A j,1 , B j,1 , A j,2 , B j,2 , A j,3 , B j,3 represents the undetermined coefficient; represents the bottom hole pressure solution in zone 1 converted to Laplace space; represents the bottom hole pressure solution in zone 2 converted to Laplace space; represents the bottom hole pressure solution of the third zone converted to Laplace space; I0 represents the first type of zero-order modified Bessel function; s represents the ideal solution; K0 represents the second type of zero-order modified Bessel function;

[0050] The unknown coefficients are substituted into the boundary and initial conditions to establish a system of six linear equations. There are six unknowns in total. The solution is A. j,1 , B j,1 , and then substitute it into the solution of bottom hole pressure

[0051]

[0052] According to the Duhamel principle, the stratified yield contribution formula is obtained:

[0053]

[0054] In the formula, represents the dimensionless output at the jth level in Laplace space; represents the actual pressure at the bottom of the well in Laplace space;

[0055] Substituting the pressure solution into the layered production contribution equation, we can obtain Then, the Stehfest numerical inversion method is used to obtain the dimensionless stratified production q in real space. jD ;

[0056] r D The BL theory is applied to solve the dimensionless distance from the water flooding front to the well. However, considering that CO2 in the gas component will dissolve in the edge water, the BL equation needs to be modified.

[0057] Preferably, the process of correcting the BL equation is:

[0058] Referring to the one-dimensional CO2 flooding model, a one-dimensional water flooding gas non-piston model was established, and the BL equation was modified. The conservation equation of the molar concentration of the CO2 component in the form of the model flow rate is:

[0059]

[0060]

[0061]

[0062]

[0063]

[0064] In the formula, Represents the total molar concentration of CO2 in the gas phase and the water phase; Indicates the total CO2 fraction; S g Indicates gas saturation; f g represents the CO2 fraction; q represents the bottom hole production of the gas well; B represents the average volume coefficient of gas in the near-well gas zone of each layer; t represents the production time; Indicates the CO2 concentration in the gas zone; Indicates the CO2 concentration in the water area; represents the formation porosity; A represents the seepage cross-sectional area; L represents the formation length; x represents the seepage length; T D represents the dimensionless gas cumulative output volume; x D It represents the dimensionless distance of the one-dimensional CO2 flooding model;

[0065] The moving speed v of the profile of constant CO2 concentration CO2 The expression is:

[0066]

[0067] In the formula, represents the CO2 fractional flow difference; represents the CO2 concentration difference; Indicates the CO2 split flow at the top of the split flow curve; Indicates the CO2 split flow at the bottom of the split flow curve; Indicates the CO2 concentration at the top of the split flow curve; Indicates the CO2 concentration at the bottom of the split flow curve;

[0068] Take the first layer of the model as an example. Figure 3 Derivation of the velocity of the water-driven gas front and trailing edge moving speed They are:

[0069]

[0070]

[0071]

[0072]

[0073] In the formula, It represents the ordinate value of the flow distribution curve at the front edge of the second zone; It represents the abscissa value of the flow distribution curve at the front edge of zone 2; It represents the ordinate value of the flow distribution curve at the trailing edge of zone 1; It represents the horizontal coordinate value of the flow distribution curve at the trailing edge of zone 1; represents the concentration of CO2 at the trailing edge of zone 1; f g Ⅱ- Represents the relative fractional flow of gas phase at the front edge of zone 2; S g Ⅱ- Indicates the gas saturation at the front edge of the second zone; D I-Ⅱ represents the seepage resistance coefficient of the first and second zones; S g,I-Ⅱ Indicates the gas saturation conditions of the first and second zones; f g Indicates CO2 split flow; S g Indicates gas saturation; It represents the ordinate of the flow curve at the rear edge of zone 2; represents the horizontal coordinate of the flow curve at the rear edge of zone 2; f g Ⅱ+ Represents the relative flow rate of gas phase at the trailing edge of zone 2; S g Ⅱ+ Indicates the gas saturation at the rear edge of zone 2; D Ⅱ-Ⅲ represents the seepage resistance coefficient of the second and third zones; S g,Ⅱ-Ⅲ Indicates the gas saturation conditions in Zones 2 and 3; represents the front concentration of CO2 in the water phase of zone 2; It represents the front concentration of CO2 in the gas phase of zone 2; represents the trailing edge concentration of CO2 in the water phase of zone 2; represents the trailing edge concentration of CO2 in the gas phase of zone 2;

[0074] The one-dimensional water-driven gas front and rear moving velocities are converted into plane radial flow to adapt to the derivation of the complex gas-water seepage equation. The plane radial flow velocity is characterized by:

[0075]

[0076] Where r is the radius of the radial cylinder; h is j represents the thickness of the jth layer of the reservoir;

[0077] Separate and integrate the above formula:

[0078]

[0079] In the formula, r e Represents the outer boundary radius of the formation; rw represents the true well radius;

[0080] Make the above equation dimensionless and ignore r w , r w ≤r e :

[0081]

[0082]

[0083]

[0084] Where, t D represents dimensionless time; r eD represents the dimensionless outer boundary radius of the stratum; T D It represents the dimensionless cumulative gas production volume;

[0085] Since the production splitting in the initial stage is affected by data, the accuracy is low and the actual production fluctuation trend is not shown, real-time production data update is introduced to realize the multi-layer combined production theoretical splitting model considering variable production:

[0086] q=q 实时

[0087] t=t 实时

[0088] In the formula, q 实时 Indicates the actual gas production rate; t 实时 Indicates the actual production time.

[0089] Preferably, in step S3, establishing a multi-layer commingled production splitting method based on component correction includes:

[0090] Assume a multi-layer commingled mining model, and it is known that the real-time splitting ratios of each layer are H1, H2, ..., H n The hydrocarbon contents of each layer are C1, C2...C n , then the wellhead commingled production component C 总 for:

[0091] C 总 =H1×C1+H2×C2+……+H n ×C n

[0092] In actual production, the wellhead commingled production group is divided into daily detection data, so C 总The parameters are known, but the real-time splitting ratio of each layer and the hydrocarbon content of each layer cannot be determined. There are experimental data for hydrocarbon content. Therefore, when there is an error between the theoretical model of dynamic production splitting of multi-layer combined production wells and the actual production data, the theoretical model is corrected according to the actual production data to improve the accuracy of the model.

[0093] Preferably, the enumeration method and the least square method are introduced to improve the accuracy of the model, and a mathematical model is established based on experimental and dynamic data for calculation: a least square method mathematical model is established based on known single-layer hydrocarbon content experimental data, and real-time single-layer hydrocarbon content data is obtained. The steps of establishing the least square method mathematical model are as follows:

[0094] Construct a polynomial fitting function P n (x):

[0095] P n (x) = a0 + a1x + a2x 2 +……+a n x n

[0096] Each deviation r i It is expressed as:

[0097] r i =P n (x i )-y i (i=1,2,3,……,n)

[0098] In order to satisfy the least squares fitting criteria, then:

[0099]

[0100] In the formula, a0 to a n They represent the unknown coefficients respectively; x n represents a set of linearly independent functions; x i represents the observed data; y i represents the observed value; m represents the number of data sets; min represents the minimum value of unconstrained optimization;

[0101] make Find the minimum value of F, so for the multivariate function F(a0, a1, ..., a n ) Take the partial derivative and set the derivative value to 0 to find the stationary point:

[0102]

[0103] After calculating the single-layer components with experimental data, in order to avoid the influence of subjective factors, the other components are selected by enumeration method. In order to improve the reliability and accuracy of the results, the range is constrained. The accurate stage of the calculation results of the multi-layer combined production well dynamic production splitting theoretical model is selected. Due to the influence of inter-layer interference, the component data at this stage is selected to fluctuate up and down by 5% as a constraint condition.

[0104] Preferably, the steps of obtaining the remaining layer components except the single layer components with experimental data by enumeration method are:

[0105] The values ​​generated by enumeration method are compared with the constraints, and the values ​​that meet the requirements are used for the next step of calculation. If they do not meet the requirements, new values ​​will be selected for judgment calculation;

[0106] Substituting the two-layer component data solved by the dual model of enumeration method and least square method into the multi-layer combined mining model, the actual splitting ratio of the single layer and the actual splitting ratio of the remaining layers can be solved. Based on this result, the splitting result can be corrected, greatly improving the calculation accuracy of the model;

[0107] The initial splitting yield is replaced by the inferred splitting yield, and the calculation is repeated to determine the single-layer components and splitting ratios at different times, until the inferred splitting yields at different time points tend to the initial splitting yield, and the correction is completed.

[0108] Compared with the prior art, the multi-layer combined production splitting method of the present invention has the following beneficial effects:

[0109] The present invention can more accurately and in real time characterize the dynamic splitting ratio of each layer. The method has strong adaptability and can establish high-precision splitting equations specifically for different gas layers. The required data volume is small and the splitting accuracy is stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0110] Figure 1 Flow chart of a multi-layer commingled production splitting method in an embodiment of the present invention;

[0111] Figure 2 It is a cross-sectional diagram of the physical model of production splitting of a multi-layer combined production well in an embodiment of the present invention;

[0112] Figure 3 This is the change diagram of the combined hydrocarbon content before logging correction;

[0113] Figure 4 This is the change diagram of the combined hydrocarbon content after well logging correction;

[0114] Figure 5 This is a graph showing the actual changes in the combined hydrocarbon content in well logging. DETAILED DESCRIPTION

[0116] The present invention will be further described below in conjunction with specific implementation modes.

[0117] Example 1

[0118] A multi-layer commingled production splitting method, such as Figure 1 As shown, the following steps are included:

[0119] S1: Conduct multi-tube parallel core physical experiments to clarify the main controlling factors of production changes in multi-layer commingled production wells;

[0120] S2: A multi-layer commingled mining theoretical splitting model is constructed based on the main controlling factors as the basic parameters, and the multi-layer commingled mining theoretical splitting model is improved by introducing the correction of the moving speed of the leading and trailing edges by components;

[0121] S3: Establish a multi-layer commingled production splitting method based on component correction, and use the component change law to correct the improved theoretical model.

[0122] The above-mentioned multi-layer commingled production splitting method constructs a multi-layer commingled production theoretical splitting model on the basis of determining the main controlling factors, and uses the component change law to correct the model. It requires a small amount of data, has high splitting accuracy and stable splitting accuracy.

[0123] In step S1, the device for carrying out the multi-tube parallel core physical experiment includes a formation water sampler, a crude oil sampler, a gas sampler, a first double-cylinder displacement pump, a second double-cylinder displacement pump, a third double-cylinder displacement pump, a formation water intermediate container, a crude oil intermediate container, a gas intermediate container, a pressure sensor, a confining pressure pump, a six-way valve, a back pressure valve, and a flow controller, and a first core clamp, a second core clamp, and a third core clamp connected in parallel through the six-way valve, and the first core clamp, the second core clamp, and the third core clamp are connected in parallel. The devices are respectively connected to the confining pressure pumps, the first double-cylinder displacement pump is connected to the first core clamp through the formation water intermediate container, the formation water sampler is connected to the formation water intermediate container in parallel, the second double-cylinder displacement pump is connected to the second core clamp through the crude oil intermediate container, the crude oil sampler is connected to the crude oil intermediate container in parallel, the third double-cylinder displacement pump is connected to the third core clamp through the gas intermediate container, the gas sampler is connected to the gas intermediate container in parallel, the back pressure valve is arranged between the six-way valve and the flow control meter, and the pressure sensors are respectively arranged on the core clamps.

[0124] In step S1, by changing the core permeability, core length and displacement pressure, the influence of layer physical property differences, reserves, pressure difference and water invasion factors on production splitting during multi-layer production is simulated to determine the main controlling factors of core-scale gas production contribution.

[0125] In step S1, for the single-tube experiment of constant pressure difference water drive gas, the main controlling factors include permeability and CO2 content; for the parallel depletion experiment, the main controlling factors include permeability, fluid flow rate, porosity and comprehensive compression coefficient; for the parallel fixed inlet flow rate and fixed outlet pressure test, the main controlling factors include injection rate; for the parallel fixed inlet pressure and fixed outlet flow rate test, the main controlling factors include permeability, injection pressure and total production rate.

[0126] In step S2, the process of establishing the multi-layer commingled production theoretical splitting model is as follows:

[0127] Assume that the physical model of multi-layer commingled production well production splitting is as follows: Figure 2 As shown: circular formation, horizontal, homogeneous, unequal thickness, impermeable layers between upper and lower layers, a production well in the center of the circular formation, constant flow rate gas production; the reservoir space contains bound water saturation, and the dissolution of CO2 in the gas component in water is considered, the diffusion of water phase in the gas is not considered, and the physical and chemical reactions of rocks are not considered; the edge water energy is sufficient, the fluid is compressible, the development process is isothermal, the flow follows Darcy's law and the influence of capillary force and gravity are ignored; the physical stage studied is before water appears in the production well, that is, the water drive gas only production stage;

[0128] A dimensionless mathematical model is established, and the radial coordinate seepage partial differential equation of the vertical well in the kth zone of the jth layer and its initial conditions, inner boundary adjustment, outer boundary conditions, and connection conditions are as follows:

[0129]

[0130]

[0131]

[0132]

[0133]

[0134]

[0135]

[0136]

[0137]

[0138]

[0139] in:

[0140]

[0141]

[0142]

[0143]

[0144]

[0145]

[0146]

[0147]

[0148]

[0149]

[0150]

[0151]

[0152]

[0153]

[0154]

[0155]

[0156]

[0157] In the formula, It means to find partial derivatives of parameters; represents dimensionless pressure; r D represents dimensionless distance; ω jk represents the dimensionless storage capacity coefficient of the kth zone of the jth layer; x jk represents the interlayer flow coefficient ratio of the jth layer and the kth zone; t D represents dimensionless time; represents the dimensionless radius of the kth zone of the jth layer; Represents dimensionless effective well diameter; q jD represents the dimensionless output of the jth layer; represents the dimensionless bottom hole pressure; represents the original dimensionless pressure; r wejD represents the dimensionless effective well radius of the jth layer; r ejD represents the dimensionless outer boundary distance of the jth layer; λ j represents the partition flow ratio; r represents the radial cylinder radius; h t Indicates the total storage thickness; h jrepresents the reservoir thickness of the jth layer; Indicates the average interlayer flow rate of the thickness clamp; K j,1 represents the formation permeability of the first zone of the jth layer; K j,2 represents the formation permeability of the second zone of the jth layer; K j,3 represents the formation permeability of zone 3 in layer j; represents the gas phase permeability in the first zone of the jth layer; represents the gas phase permeability in the second zone of the jth layer; represents the relative water permeability of zone 2 in layer j; represents the relative water permeability of the third zone of the jth layer; μ g,j,1 represents the gas viscosity of the first zone of the jth layer; μ g,j,2 represents the gas viscosity of the second zone of the jth layer; μ g,j,3 represents the gas viscosity of the third zone of the jth layer; μ w,j,2 represents the water viscosity in the second zone of the jth layer; μ w,j,3 represents the water viscosity in zone 3 of layer j; Indicates gas-water two-phase drive in zone 2; Φ j,1 represents the porosity of the first zone of the jth layer; Φ j,2 represents the porosity of the second zone of the jth layer; Φ j,3 represents the porosity of the third zone of the jth layer; C tj,1 represents the comprehensive compression coefficient of the first zone of the jth layer; C tj,2 represents the comprehensive compression coefficient of the second zone of the jth layer; C tj,3 represents the comprehensive compression factor of the third zone of the jth layer; Indicates the reference pressure; represents the formation pressure in zone 1 of layer j; represents the formation pressure in zone 2 of layer j; represents the formation pressure in the third zone of the jth layer; (ΦC t ) a represents the average storage coefficient of the layers weighted by thickness; q represents the bottom hole production of the gas well; B represents the average volume coefficient of gas in the near-well gas zone of each layer; B j represents the average volume coefficient of the j-th layer of gas; q jD represents the dimensionless stratified output in real space; q j represents the output of the jth layer; B j represents the gas volume coefficient of the jth layer; S j represents the skin factor of the jth layer; r w represents the true well radius; indicates; r ej Represents the outer boundary radius of the jth layer; r ejDRepresents the dimensionless outer boundary radius of the jth layer; wherein, the first zone I of the first layer, the first zone IV of the second layer, and the first zone VII of the third layer represent the gas zone of the edge water constant pressure boundary; the second zone II of the first layer, the second zone V of the second layer, and the second zone VIII of the third layer represent the gas-water mixed zone of the edge water constant pressure boundary; the third zone III of the first layer, the third zone VI of the second layer, and the third zone IX of the third layer represent the water zone of the edge water constant pressure boundary.

[0158] To solve the dimensionless mathematical model, we need to transform it into Laplace space first, and then solve it to get the general solution containing Bessel function:

[0159]

[0160] In the formula, A j,1 , B j,1 , A j,2 , B j,2 , A j,3 , B j,3 represents the undetermined coefficient; represents the bottom hole pressure solution in zone 1 converted to Laplace space; represents the bottom hole pressure solution in zone 2 converted to Laplace space; represents the bottom hole pressure solution of the third zone converted to Laplace space; I0 represents the first type of zero-order modified Bessel function; s represents the ideal solution; K0 represents the second type of zero-order modified Bessel function;

[0161] The unknown coefficients are substituted into the boundary and initial conditions to establish a system of six linear equations. There are six unknowns in total. The solution is A. j,1 , B j,1 , and then substitute it into the solution of bottom hole pressure

[0162]

[0163] According to the Duhamel principle, the stratified yield contribution formula is obtained:

[0164]

[0165] In the formula, represents the dimensionless output at the jth level in Laplace space; represents the actual pressure at the bottom of the well in Laplace space;

[0166] Substituting the pressure solution into the layered production contribution equation, we can obtain Then, the Stehfest numerical inversion method is used to obtain the dimensionless stratified production q in real space. jD ;

[0167] r DThe BL theory is applied to solve the dimensionless distance from the water flooding front to the well. However, considering that CO2 in the gas component will dissolve in the edge water, the BL equation needs to be modified.

[0168] Example 2

[0169] This embodiment is similar to Embodiment 1, except that the process of correcting the BL equation is:

[0170] Referring to the one-dimensional CO2 flooding model, a one-dimensional water flooding gas non-piston model was established, and the BL equation was modified. The conservation equation of the molar concentration of the CO2 component in the form of the model flow rate is:

[0171]

[0172]

[0173]

[0174]

[0175]

[0176] In the formula, Represents the total molar concentration of CO2 in the gas phase and the water phase; Indicates the total CO2 fraction; S g Indicates gas saturation; f g represents the CO2 fraction; q represents the bottom hole production of the gas well; B represents the average volume coefficient of gas in the near-well gas zone of each layer; t represents the production time; Indicates the CO2 concentration in the gas zone; Indicates the CO2 concentration in the water area; represents the formation porosity; A represents the seepage cross-sectional area; L represents the formation length; x represents the seepage length; T D represents the dimensionless gas cumulative output volume; x D It represents the dimensionless distance of the one-dimensional CO2 flooding model;

[0177] The moving speed of the profile of the same CO2 concentration The expression is:

[0178]

[0179] In the formula, represents the CO2 fractional flow difference; represents the CO2 concentration difference; Indicates the CO2 split flow at the top of the split flow curve; Indicates the CO2 split flow at the bottom of the split flow curve; Indicates the CO2 concentration at the top of the split flow curve; Indicates the CO2 concentration at the bottom of the split flow curve;

[0180] For the first layer of the model, the velocity of the water-driven gas front is derived as and trailing edge moving speed They are:

[0181]

[0182]

[0183]

[0184]

[0185] In the formula, It represents the ordinate value of the flow distribution curve at the front edge of the second zone; It represents the abscissa value of the flow distribution curve at the front edge of zone 2; It represents the ordinate value of the flow distribution curve at the trailing edge of zone 1; It represents the horizontal coordinate value of the flow distribution curve at the trailing edge of zone 1; represents the concentration of CO2 at the trailing edge of zone 1; f g Ⅱ- Represents the relative fractional flow of gas phase at the front edge of zone 2; S g Ⅱ- Indicates the gas saturation at the front edge of the second zone; D I-Ⅱ represents the seepage resistance coefficient of the first and second zones; S g,I-Ⅱ Indicates the gas saturation conditions of the first and second zones; f g Indicates CO2 split flow; S g Indicates gas saturation; It represents the ordinate of the flow curve at the rear edge of zone 2; represents the horizontal coordinate of the flow curve at the rear edge of zone 2; f g Ⅱ+ Represents the relative flow rate of gas phase at the trailing edge of zone 2; S g Ⅱ+ Indicates the gas saturation at the rear edge of zone 2; D Ⅱ-Ⅲ represents the seepage resistance coefficient of the second and third zones; S g,Ⅱ-Ⅲ Indicates the gas saturation conditions in Zones 2 and 3; represents the front concentration of CO2 in the water phase of zone 2; represents the front concentration of CO2 in the gas phase of zone 2, represents the trailing edge concentration of CO2 in the water phase of zone 2; represents the trailing edge concentration of CO2 in the gas phase of zone 2;

[0186] The one-dimensional water-driven gas front and rear moving velocities are converted into plane radial flow to adapt to the derivation of the complex gas-water seepage equation. The plane radial flow velocity is characterized by:

[0187]

[0188] Where r is the radius of the radial cylinder; h is j represents the thickness of the jth layer of the reservoir;

[0189] Separate and integrate the above formula:

[0190]

[0191] In the formula, r e Represents the outer boundary radius of the formation; r w represents the true well radius;

[0192] Make the above equation dimensionless and ignore r w , r w ≤r e :

[0193]

[0194]

[0195]

[0196] Where t D represents dimensionless time; r eD represents the dimensionless outer boundary radius of the stratum; T D It represents the dimensionless cumulative gas production volume;

[0197] Since the production splitting in the initial stage is affected by data, the accuracy is low and the actual production fluctuation trend is not shown, real-time production data update is introduced to realize the multi-layer combined production theoretical splitting model considering variable production:

[0198] q=q 实时

[0199] t=t 实时

[0200] In the formula, q 实时 Indicates the actual gas production rate; t 实时 Indicates the actual production time.

[0201] Example 3

[0202] This embodiment is similar to Embodiment 2, except that, in step S3, establishing a multi-layer commingled production splitting method based on component correction includes:

[0203] Assume a multi-layer commingled mining model, and it is known that the real-time splitting ratios of each layer are H1, H2, ..., H n The hydrocarbon contents of each layer are C1, C2...C n , then the wellhead commingled production component C 总 for:

[0204] C 总 =H1×C1+H2×C2+……+H n ×C n

[0205] In actual production, the wellhead commingled production group is divided into daily detection data, so C 总 The parameters are known, but the real-time splitting ratio of each layer and the hydrocarbon content of each layer cannot be determined. There are experimental data for hydrocarbon content. Therefore, when there is an error between the theoretical model of dynamic production splitting of multi-layer combined production wells and the actual production data, the theoretical model is corrected according to the actual production data to improve the accuracy of the model.

[0206] The enumeration method and the least square method are introduced to improve the accuracy of the model. A mathematical model is established based on experimental and dynamic data for calculation: Based on the known experimental data of single-layer hydrocarbon content, a least square method mathematical model is established to obtain real-time single-layer hydrocarbon content data. The steps for establishing the least square method mathematical model are as follows:

[0207] Construct a polynomial fitting function P n (x):

[0208] P n (x) = a0 + a1x + a2x 2 +……+a n x n

[0209] Each deviation r i It is expressed as:

[0210] r i =P n (x i )-y i (i=1,2,3,……,n)

[0211] In order to satisfy the least squares fitting criteria, then:

[0212]

[0213] In the formula, a0 to a n They represent the unknown coefficients respectively; x n represents a set of linearly independent functions; x i represents the observed data; y i represents the observed value; m represents the number of data sets; min represents the minimum value of unconstrained optimization;

[0214] make Find the minimum value of F, so for the multivariate function F(a0, a1, ..., a n ) Take the partial derivative and set the derivative value to 0 to find the stationary point:

[0215]

[0216] After calculating the single-layer components with experimental data, in order to avoid the influence of subjective factors, the other components are selected by enumeration method. In order to improve the reliability and accuracy of the results, the range is constrained. The accurate stage of the calculation results of the multi-layer combined production well dynamic production splitting theoretical model is selected. Due to the influence of inter-layer interference, the component data at this stage is selected to fluctuate up and down by 5% as a constraint condition.

[0217] The steps of enumeration method to obtain the remaining layer components except the single layer components with experimental data are as follows:

[0218] The values ​​generated by enumeration method are compared with the constraints, and the values ​​that meet the requirements are used for the next step of calculation. If they do not meet the requirements, new values ​​will be selected for judgment calculation;

[0219] Substituting the two-layer component data solved by the dual model of enumeration method and least square method into the multi-layer combined mining model, the actual splitting ratio of the single layer and the actual splitting ratio of the remaining layers can be solved. Based on this result, the splitting result can be corrected, greatly improving the calculation accuracy of the model, such as Figures 3 to 5 As shown;

[0220] The initial splitting yield is replaced by the inferred splitting yield, and the calculation is repeated to determine the single-layer components and splitting ratios at different times, until the inferred splitting yields at different time points tend to the initial splitting yield, and the correction is completed.

[0221] In the specific contents of the above-mentioned specific implementation methods, the various technical features can be combined in any non-contradictory manner. In order to make the description concise, not all possible combinations of the above-mentioned technical features are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0222] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A multi-layer commingled production splitting method, characterized in that: The following steps are involved: S1: Conduct multi-tube parallel core physical experiments to clarify the main controlling factors of production changes in multi-layer commingled production wells; S2: A multi-layer commingled mining theoretical splitting model is constructed based on the main controlling factors as the basic parameters, and the multi-layer commingled mining theoretical splitting model is improved by introducing the correction of the moving speed of the leading and trailing edges by components; S3: Establish a multi-layer commingled production splitting method based on component correction, and use the component change law to correct the improved theoretical model.

2. The multi-layer commingled production splitting method according to claim 1, characterized in that: In step S1, the device for carrying out the multi-tube parallel core physical experiment includes a formation water sampler, a crude oil sampler, a gas sampler, a first double-cylinder displacement pump, a second double-cylinder displacement pump, a third double-cylinder displacement pump, a formation water intermediate container, a crude oil intermediate container, a gas intermediate container, a pressure sensor, a confining pressure pump, a six-way valve, a back pressure valve, and a flow controller, and a first core holder, a second core holder, and a third core holder connected in parallel through the six-way valve, wherein the first core holder, the second core holder, and the third core holder are respectively connected to the confining pressure pump, and the first double-cylinder drive pump is connected to the confining pressure pump. The displacement pump is connected to the first core clamp through the formation water intermediate container, the formation water sampler is connected in parallel with the formation water intermediate container, the second double-cylinder displacement pump is connected to the second core clamp through the crude oil intermediate container, the crude oil sampler is connected in parallel with the crude oil intermediate container, the third double-cylinder displacement pump is connected to the third core clamp through the gas intermediate container, the gas sampler is connected in parallel with the gas intermediate container, the back pressure valve is arranged between the six-way valve and the flow control meter, and the pressure sensors are respectively arranged in the core clamps.

3. The multi-layer commingled production splitting method according to claim 2, characterized in that: In step S1, by changing the core permeability, core length and displacement pressure, the influence of layer physical property differences, reserves, pressure difference and water invasion factors on production splitting during multi-layer production is simulated to determine the main controlling factors of core-scale gas production contribution.

4. The multi-layer commingled production splitting method according to claim 2, characterized in that: In step S1, for the single-tube experiment of constant pressure difference water drive gas, the main controlling factors include permeability and CO2 content; for the parallel depletion experiment, the main controlling factors include permeability, fluid flow rate, porosity and comprehensive compression coefficient; for the parallel fixed inlet flow rate and fixed outlet pressure test, the main controlling factors include injection rate; for the parallel fixed inlet pressure and fixed outlet flow rate test, the main controlling factors include permeability, injection pressure and total production rate.

5. The multi-layer commingled production splitting method according to claim 1, characterized in that: In step S2, the process of establishing the multi-layer commingled production theoretical splitting model is as follows: Assumptions: circular formation, horizontal, homogeneous, unequal thickness, impermeable layers between upper and lower layers, one production well in the center of the circular formation, producing gas at a constant flow rate; the reservoir space contains bound water saturation, and the dissolution of CO2 in the gas component in water is considered, the diffusion of water phase in gas is not considered, and the physical and chemical reactions of rocks are not considered; the edge water energy is sufficient, the fluid is compressible, the development process is isothermal, the flow follows Darcy's law, and the influence of capillary force and gravity are ignored; the physical stage studied is before water appears in the production well, that is, the water drive gas only production stage; A dimensionless mathematical model is established, and the radial coordinate seepage partial differential equation of the vertical well in the kth zone of the jth layer and its initial conditions, inner boundary adjustment, outer boundary conditions, and connection conditions are as follows: in: In the formula, It means to find partial derivatives of parameters; represents dimensionless pressure; r D represents dimensionless distance; ω jk represents the dimensionless storage capacity coefficient of the kth zone of the jth layer; x jk represents the interlayer flow coefficient ratio of the jth layer and the kth zone; t D represents dimensionless time; represents the dimensionless radius of the kth zone of the jth layer; Represents dimensionless effective well diameter; q jD represents the dimensionless output of the jth layer; represents the dimensionless bottom hole pressure; represents the original dimensionless pressure; r wejD represents the dimensionless effective well radius of the jth layer; r ejD represents the dimensionless outer boundary distance of the jth layer; λ j represents the partition flow ratio; r represents the radial cylinder radius; h t Indicates the total storage thickness; h j represents the reservoir thickness of the jth layer; Indicates the average interlayer flow rate of the thickness clamp; K j,1 represents the formation permeability of the first zone of the jth layer; K j,2 represents the formation permeability of the second zone of the jth layer; K j,3 represents the formation permeability of zone 3 in layer j; represents the gas phase permeability in the first zone of the jth layer; represents the gas phase permeability in the second zone of the jth layer; represents the relative water permeability of zone 2 in layer j; represents the relative water permeability of the third zone of the jth layer; μ g,j,1 represents the gas viscosity of the first zone of the jth layer; μ g,j,2 represents the gas viscosity of the second zone of the jth layer; μ g,j,3 represents the gas viscosity of the third zone of the jth layer; μ w,j,2 represents the water viscosity in the second zone of the jth layer; μ w,j,3 represents the water viscosity in zone 3 of layer j; Indicates gas-water two-phase drive in zone 2; Φ j,1 represents the porosity of the first zone of the jth layer; Φ j,2 represents the porosity of the second zone of the jth layer; Φ j,3 represents the porosity of the third zone of the jth layer; C tj,1 represents the comprehensive compression coefficient of the first zone of the jth layer; C tj,2 represents the comprehensive compression coefficient of the second zone of the jth layer; C tj,3 represents the comprehensive compression factor of the third zone of the jth layer; Indicates the reference pressure; represents the formation pressure in zone 1 of layer j; represents the formation pressure in zone 2 of layer j; represents the formation pressure in the third zone of the jth layer; (ΦC t ) a represents the average storage coefficient of the layers weighted by thickness; q represents the bottom hole production of the gas well; B represents the average volume coefficient of gas in the near-well gas zone of each layer; B j represents the average volume coefficient of the j-th layer of gas; q jD represents the dimensionless stratified output in real space; q j represents the output of the jth layer; B j represents the gas volume coefficient of the jth layer; S j represents the skin factor of the jth layer; r w represents the true well radius; indicates; r ej Represents the outer boundary radius of the jth layer; r ejD Represents the dimensionless outer boundary radius of the jth layer; wherein, the first zone I of the first layer, the first zone IV of the second layer, and the first zone VII of the third layer represent the gas zone of the edge water constant pressure boundary; the second zone II of the first layer, the second zone V of the second layer, and the second zone VIII of the third layer represent the gas-water mixed zone of the edge water constant pressure boundary; the third zone III of the first layer, the third zone VI of the second layer, and the third zone IX of the third layer represent the water zone of the edge water constant pressure boundary.

6. The multi-layer commingled production splitting method according to claim 5, characterized in that: To solve the dimensionless mathematical model, we need to transform it into Laplace space first, and then solve it to get the general solution containing Bessel function: In the formula, A j,1 , B j,1 , A j,2 , B j,2 , A j,3 , B j,3 represents the undetermined coefficient; represents the bottom hole pressure solution in zone 1 converted to Laplace space; represents the bottom hole pressure solution in zone 2 converted to Laplace space; represents the bottom hole pressure solution of the third zone converted to Laplace space; I0 represents the first type of zero-order modified Bessel function; s represents the ideal solution; K0 represents the second type of zero-order modified Bessel function; The unknown coefficients are substituted into the boundary and initial conditions to establish a system of six linear equations. There are six unknowns in total. The solution is A. j,1 , B j,1 , and then substitute it to get the ideal bottom hole pressure solution According to the Duhamel principle, the stratified yield contribution formula is obtained: In the formula, represents the dimensionless output at the jth level in Laplace space; represents the actual pressure at the bottom of the well in Laplace space; Substituting the pressure solution into the layered production contribution equation, we can obtain Then, the Stehfest numerical inversion method is used to obtain the dimensionless stratified production q in real space. jD ; r D The BL theory is applied to solve the dimensionless distance from the water flooding front to the well. However, considering that CO2 in the gas component will dissolve in the edge water, the BL equation needs to be modified.

7. The multi-layer commingled production splitting method according to claim 6, characterized in that: The process of correcting the BL equation is: Referring to the one-dimensional CO2 flooding model, a one-dimensional water flooding gas non-piston model was established, and the BL equation was modified. The conservation equation of the molar concentration of the CO2 component in the form of the model flow rate is: In the formula, Represents the total molar concentration of CO2 in the gas phase and the water phase; Indicates the total CO2 fraction; S g Indicates gas saturation; f g represents the CO2 fraction; q represents the bottom hole production of the gas well; B represents the average volume coefficient of gas in the near-well gas zone of each layer; t represents the production time; Indicates the CO2 concentration in the gas zone; Indicates the CO2 concentration in the water area; represents the formation porosity; A represents the seepage cross-sectional area; L represents the formation length; x represents the seepage length; T D represents the dimensionless gas cumulative output volume; x D It represents the dimensionless distance of the one-dimensional CO2 flooding model; The moving speed v of the profile of constant CO2 concentration CO2 The expression is: In the formula, represents the CO2 fractional flow difference; represents the CO2 concentration difference; Indicates the CO2 split flow at the top of the split flow curve; Indicates the CO2 split flow at the bottom of the split flow curve; Indicates the CO2 concentration at the top of the split flow curve; Indicates the CO2 concentration at the bottom of the split flow curve; For the first layer of the model, the velocity of the water-driven gas front is derived as and trailing edge moving speed They are: In the formula, It represents the ordinate value of the flow distribution curve at the front edge of the second zone; It represents the abscissa value of the flow distribution curve at the front edge of zone 2; It represents the ordinate value of the flow distribution curve at the trailing edge of zone 1; It represents the horizontal coordinate value of the flow distribution curve at the trailing edge of zone 1; represents the concentration of CO2 at the trailing edge of zone 1; f g Ⅱ- Represents the relative fraction of gas phase at the front edge of zone 2; S g Ⅱ- Indicates the gas saturation at the front edge of the second zone; D I-Ⅱ represents the seepage resistance coefficient of the first and second zones; S g,I-Ⅱ Indicates the gas saturation conditions of the first and second zones; f g Indicates CO2 split flow; S g Indicates gas saturation; It represents the ordinate of the flow curve of the rear edge of the second zone; It represents the horizontal coordinate of the flow curve at the rear edge of the second zone; f g Ⅱ+ Represents the relative flow rate of gas phase at the trailing edge of zone 2; S g Ⅱ+ Indicates the gas saturation at the rear edge of zone 2; D Ⅱ-Ⅲ represents the seepage resistance coefficient of the second and third zones; S g,Ⅱ-Ⅲ Indicates the gas saturation conditions in Zones 2 and 3; represents the front concentration of CO2 in the water phase of zone 2; represents the front concentration of CO2 in the gas phase of zone 2, represents the trailing edge concentration of CO2 in the water phase of zone 2; represents the trailing edge concentration of CO2 in the gas phase of zone 2; The one-dimensional water-driven gas front and rear moving velocities are converted into plane radial flow to adapt to the derivation of the complex gas-water seepage equation. The plane radial flow velocity is characterized by: Where r is the radius of the radial cylinder; h is j represents the thickness of the jth layer of the reservoir; Separate and integrate the above formula: In the formula, r e Represents the outer boundary radius of the formation; r w represents the true well radius; Make the above equation dimensionless and ignore r w , r w ≤r e : Where, t D represents dimensionless time; r eD represents the dimensionless outer boundary radius of the stratum; T D It represents the dimensionless cumulative gas production volume; Since the production splitting in the initial stage is affected by data, the accuracy is low and the actual production fluctuation trend is not shown, real-time production data update is introduced to realize the multi-layer combined production theoretical splitting model considering variable production: q=q 实时 t=t 实时 In the formula, q 实时 Indicates the actual production gas rate; t 实时 Indicates the actual production time.

8. The multi-layer commingled production splitting method according to claim 7, characterized in that: In step S3, establishing a multi-layer commingled production splitting method based on component correction includes: Assume a multi-layer commingled mining model, and it is known that the real-time splitting ratios of each layer are H1, H2, ..., H n The hydrocarbon contents of each layer are C1, C2...C n , then the wellhead commingled production component C 总 for: C 总 =H1×C1+H2×C2+……+H n ×C n In actual production, the wellhead commingled production group is divided into daily detection data, so C 总 The parameters are known, but the real-time splitting ratio of each layer and the hydrocarbon content of each layer cannot be determined. There are experimental data for hydrocarbon content. Therefore, when there is an error between the theoretical model of dynamic production splitting of multi-layer combined production wells and the actual production data, the theoretical model is corrected according to the actual production data to improve the accuracy of the model.

9. The multi-layer commingled production splitting method according to claim 8, characterized in that: The enumeration method and the least square method are introduced to improve the accuracy of the model. A mathematical model is established based on experimental and dynamic data for calculation: Based on the known experimental data of single-layer hydrocarbon content, a least square method mathematical model is established to obtain real-time single-layer hydrocarbon content data. The steps for establishing the least square method mathematical model are as follows: Construct a polynomial fitting function P n (x): P n (x)=a0+a1x1+a2x2 2 +……+a n x n n Each deviation r i It is expressed as: r i =P n (x i )-y i (i=1,2,3,……,n) In order to satisfy the least squares fitting criteria, then: In the formula, a0 to a n They represent the unknown coefficients respectively; x n represents a set of linearly independent functions; x i represents the observed data; y i represents the observed value; m represents the number of data sets; min represents the minimum value of unconstrained optimization; make Find the minimum value of F, so for the multivariate function F(a0, a1, ..., a n ) Take the partial derivative and set the derivative value to 0 to find the stationary point: After calculating the single-layer components with experimental data, in order to avoid the influence of subjective factors, the other components are selected by enumeration method. In order to improve the reliability and accuracy of the results, the range is constrained. The accurate stage of the calculation results of the multi-layer combined production well dynamic production splitting theoretical model is selected. Due to the influence of inter-layer interference, the component data at this stage is selected to fluctuate up and down by 5% as a constraint condition.

10. The multi-layer commingled production splitting method according to claim 9, characterized in that: The steps of enumeration method to obtain the remaining layer components except the single layer components with experimental data are as follows: The values ​​generated by enumeration are compared with the constraints, and the values ​​that meet the requirements are used for the next step of calculation. If they do not meet the requirements, new values ​​will be selected for judgment calculation; Substituting the two-layer component data solved by the dual model of enumeration method and least square method into the multi-layer combined mining model, the actual splitting ratio of the single layer and the actual splitting ratio of the remaining layers can be solved. Based on this result, the splitting result can be corrected, greatly improving the calculation accuracy of the model; The initial splitting yield is replaced by the inferred splitting yield, and the calculation is repeated to determine the single-layer components and splitting ratios at different times, until the inferred splitting yields at different time points tend to the initial splitting yield, and the correction is completed.

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