CN117552781A - Method and device for predicting productivity of carbon dioxide huff and puff exploitation - Google Patents

Abstract

The invention discloses a method and a device for predicting the throughput exploitation productivity of carbon dioxide. After the huff and puff injection of the carbon dioxide, updating the saturation of each phase and the formation pressure according to the injection amount of the carbon dioxide, the volume of a transformation area, the volume of a crack in the transformation area and the original porosity; iterative execution during the stuffy phase: determining the solubility of carbon dioxide in crude oil according to the current formation pressure and temperature, updating the saturation of each current phase according to the solubility and the carbon dioxide injection amount until the well is closed, and updating the viscosity of the crude oil according to the current solubility and the oil saturation; iterative execution during the open-well production phase: five zone linear abortion based on current crude oil viscosity, carbon dioxide solubility and relative permeability of each phaseAnd carrying out multiphase splitting on the yield determined by the model to obtain the accumulated yield of each phase, and further updating the saturation of each current phase. The method derives the pressure and saturation changes of the gas injection throughput in three stages, and combines the five-zone linear abortion energy model to derive the CO ₂ Throughput capacity.

Description

Method and device for predicting productivity of carbon dioxide huff and puff exploitation

Technical Field

The invention relates to the technical field of unconventional oil and gas reservoir development, in particular to a method and a device for predicting the throughput exploitation capacity of carbon dioxide.

Background

The horizontal well volume fracturing technology is currently the main development technology of unconventional oil reservoirs such as compact oil and shale oil, plays a role in greatly improving the single well productivity, but generally has the problems of high yield decreasing speed, high stable yield difficulty, low recovery ratio and the like. Aiming at the problem of improving the recovery ratio of unconventional oil reservoirs, students at home and abroad develop a large number of gas injection throughput researches, which show that the gas injection throughput can achieve the effect of improving the single well yield and the recovery ratio, and the on-site gas injection throughput pilot test also achieves the effect, but the current research means mainly uses indoor experiments and numerical simulation researches, the indoor experiments focus on the gas injection throughput development mechanism research, the numerical simulation research needs an accurate geological model, and the research period is longer. The scholars at home and abroad also do a great deal of research on the productivity equation of the unconventional oil reservoir, but most of them are used for predicting the initial productivity of the oil well after volume fracturing, and the productivity equation for finely describing the whole gas injection throughput process is lacking in site, so that development indexes and recovery ratio can be rapidly predicted to guide development and production.

Disclosure of Invention

In view of the above problems, the present invention has been made to provide a method and apparatus for predicting the productivity of carbon dioxide throughput exploitation, which overcomes or at least partially solves the above problems, reasonably deduces the pressure and saturation changes of the three stages of gas injection throughput, and deduces CO in combination with a five-zone linear abortion energy model ₂ Throughput capacity.

In a first aspect, an embodiment of the present invention provides a method for predicting productivity of carbon dioxide huff and puff exploitation, including:

after the huff and puff injection of the carbon dioxide, the water content, the oil content, the gas content saturation and the formation pressure of the reforming region are updated according to the carbon dioxide injection amount, the volume of cracks in the oil reservoir reforming region, the volume of the reforming region, the original formation pressure, the water content saturation, the oil content saturation and the porosity;

in the well closing stage, the following steps are executed according to a first set interval: determining the solubility of carbon dioxide in crude oil according to the current stratum pressure and temperature, updating the current water, oil and gas saturation according to the solubility, the current oil saturation and the carbon dioxide injection amount until the well closing stage is finished, and determining the current crude oil viscosity according to the current solubility and the oil saturation;

in the production stage of open well, the following steps are executed according to a second set interval: according to the current crude oil viscosity, the solubility of carbon dioxide in the crude oil and the relative permeability of each phase under the current saturation condition, carrying out multiphase splitting on the current yield determined by the five-zone linear abortion energy model to obtain each phase yield, obtaining the accumulated yield of each phase after well production, and updating the current water, oil and gas saturation according to the accumulated yield of each phase and the current oil saturation.

In a second aspect, an embodiment of the present invention provides a device for predicting production capacity of carbon dioxide throughput exploitation, including:

the physical field updating module after the carbon dioxide huff and puff injection is used for updating the water content, the oil content, the gas content saturation and the formation pressure of the reforming region according to the carbon dioxide injection quantity, the crack volume in the oil reservoir reforming region, the volume of the reforming region, the original formation pressure, the water saturation, the oil content saturation and the porosity after the carbon dioxide huff and puff injection;

the physical field updating module in the well closing stage is used for executing the following steps according to a first set interval in the well closing stage: determining the solubility of carbon dioxide in crude oil according to the current stratum pressure and temperature, updating the current water, oil and gas saturation according to the solubility, the current oil saturation and the carbon dioxide injection amount until the well closing stage is finished, and determining the current crude oil viscosity according to the current solubility and the oil saturation;

the physical field updating and each-phase productivity predicting module is used for executing the following steps according to a second set interval in the well opening production stage: according to the current crude oil viscosity, the solubility of carbon dioxide in the crude oil and the relative permeability of each phase under the current saturation condition, carrying out multiphase splitting on the current yield determined by the five-zone linear abortion energy model to obtain each phase yield, obtaining the accumulated yield of each phase after well production, and updating the current water, oil and gas saturation according to the accumulated yield of each phase and the current oil saturation.

In a third aspect, an embodiment of the present invention provides a computer program product, including a computer program/instruction, where the computer program/instruction, when executed by a processor, implements the above-mentioned method for predicting carbon dioxide throughput production capacity.

In a fourth aspect, embodiments of the present disclosure provide a server, including: the system comprises a memory, a processor and a computer program stored on the memory and capable of running on the processor, wherein the processor realizes the carbon dioxide throughput exploitation productivity prediction method when executing the program.

The technical scheme provided by the embodiment of the invention has the beneficial effects that at least:

(1) The carbon dioxide throughput exploitation productivity prediction method provided by the embodiment of the invention considers CO from the gas injection throughput mechanism ₂ The gas injection throughput is divided into a gas injection supplementary energy stage, a well-closed dissolution viscosity reduction stage and a well-open stope three-phase flow stage by the supplementary energy and dissolution viscosity reduction mechanism, pressure and saturation change equations of the three stages are respectively deduced, and a horizontal well volume fracturing five-zone linear abortion energy model is combined to deduce CO ₂ Throughput capacity equation.

(2) Currently available for CO research ₂ The throughput main application software programs, such as Intersect, eclipse and other large-scale commercial numerical simulation software, adopt a numerical simulation calculation method, are high in cost, have high requirements on the running environment, have large data and have long research time. Embodiments of the invention The provided carbon dioxide huff and puff exploitation productivity prediction method adopts CO injection aiming at unconventional oil reservoirs ₂ The throughput supplementing energy development mode adopts an analysis method to evaluate the oil well production energy, and has the advantages of strong pertinence, low use cost, high running speed and convenient use compared with large-scale numerical simulation software; can evaluate different types of unconventional oil reservoirs CO ₂ Throughput capacity, simple, fast and efficient calculation method, and is more suitable for fast evaluation and comparison of on-site unconventional oil reservoir development modes and establishment of development technical policies; the amount of the resources of the covered unconventional oil reservoir reaches hundreds of billions of tons, and the application prospect is wide.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims thereof as well as the appended drawings.

The technical scheme of the invention is further described in detail through the drawings and the embodiments.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate the invention and together with the embodiments of the invention, serve to explain the invention. In the drawings:

FIG. 1 is a schematic diagram of reservoir area division after volumetric fracturing modification in accordance with an embodiment of the present invention;

FIG. 2 is a schematic diagram of reservoir seepage during the gas injection energy replenishment phase in accordance with an embodiment of the present invention;

FIG. 3 is a schematic diagram of reservoir seepage during a dissolution and viscosity reduction stage of a stuffy well in accordance with an embodiment of the present invention;

FIG. 4 is a schematic diagram of reservoir seepage during a three-phase flow phase of well recovery in accordance with an embodiment of the present invention;

FIG. 5 is a flow chart of a method for predicting throughput production of carbon dioxide in accordance with an embodiment of the present invention;

FIG. 6 is a flowchart showing the implementation of step S51 in FIG. 5;

FIG. 7 is a flowchart of a specific implementation of the viscosity update of crude oil after the completion of a stuffy well in accordance with the first embodiment of the present invention;

FIG. 8 is a comparison of analytical model calculation gas injection throughput versus numerical simulation;

FIG. 9 is a comparison of the analytical model calculated gas injection throughput formation pressure with a numerical simulation;

FIG. 10 is a flowchart of an embodiment of a carbon dioxide throughput production capacity prediction;

FIG. 11 is a schematic illustration of a reed canary-grass trench set CO in accordance with a second embodiment of the invention ₂ A comparison curve of gas injection throughput injection capacity and single well cumulative oil yield;

fig. 12 is a schematic structural diagram of a device for predicting the throughput of carbon dioxide production in an embodiment of the invention.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

Due to horizontal well CO ² The complexity of gas injection throughput exploitation mechanisms and production processes is still lacking in analytical productivity equations reflecting the complex mechanisms and development processes. The technical problems to be solved include:

(1) volumetric reconstruction reservoir CO injection ₂ Throughput development mechanism and mathematical equation

CO ₂ The gas injection throughput has a plurality of exploitation mechanisms including energy supplementing, viscosity reduction, phase mixing, oil reservoir wettability changing and the like, and all consider CO ₂ The gas injection throughput exploitation mechanism can make the analytical equation extremely complex and insoluble, and how the unconventional oil reservoir CO can be embodied ₂ The main exploitation mechanism of throughput and description of the mechanism by a mathematical model are key technical problems to be solved.

(2) Coupling productivity equation of horizontal well volume fracturing multi-scale hole seam system

Because of poor physical properties of unconventional oil reservoirs, the horizontal well needs natural capacity in a volume fracturing direction, a large number of fracturing cracks are generated in the oil reservoirs after volume fracturing, the oil reservoirs near a shaft are changed into pseudo-dual medium oil reservoirs, the oil reservoir seepage law is radically changed, the fracturing cracks and the natural cracks form a complex fracture network system, and how to consider the coupling relation among the fracturing cracks, the natural cracks and matrixes to establish a capacity equation of the horizontal well volume fracturing multi-scale hole fracture system is a key technical problem to be solved.

(3) Embody CO injection ₂ Throughput multi-cycle reservoir pressure and saturation equation of variation

CO injection ₂ Throughput and CO injection ₂ The displacement is different, the pressure and the oil-water saturation of each injection period and each production period in the huff and puff oil reservoir can be changed along with the development process, the fluid replacement effect of the oil reservoir can be continuously reduced along with the increase of the huff and puff period, and how to consider the stratum pressure distribution field and the oil-water saturation field in the whole huff and puff process is a key technical problem to be solved.

In order to solve the problems that the capacity equation in the prior art is mostly the initial capacity of an oil well after volume fracturing and the capacity prediction of the whole gas injection throughput process is lack, the embodiment of the invention provides a method and a device for predicting the productivity of carbon dioxide throughput exploitation, which can reasonably predict the pressure and saturation changes of three stages of gas injection throughput and combine a five-zone linear abortion energy model to deduce CO ₂ Throughput capacity.

1. Volumetric fracturing CO ₂ Main development mechanism research of gas injection throughput

CO ₂ The gas injection throughput has a plurality of exploitation mechanisms including energy supplementing, viscosity reduction, phase mixing, oil reservoir wettability changing and the like, and the current research results at home and abroad are synthesized, so that the Chinese land phase unconventional oil reservoir CO is considered ₂ The mining mechanism that dominates gas injection throughput includes two aspects, CO ₂ Is referred to as CO ₂ The gas is injected into the stratum, the density of the gas is small, the volume is large, and the effect of supplementing stratum energy can be better achieved; second is CO ₂ Refers to the dissolution and viscosity reduction mechanism of CO ₂ Dissolving in crude oil, reducing viscosity of crude oil, and greatly increasing fluidity of crude oilAchieving the effect of improving the productivity of a single well.

According to the embodiment of the invention, the volume-modified oil reservoir is simplified into three areas according to the modification degree, namely a main fracture, a volume modification area (simply referred to as modification area) and an unmodified area, and the three areas are shown by referring to FIG. 1.

2. Physical process and model simplification for volumetric fracturing gas injection throughput

From the gas injection throughput mechanism, consider CO ₂ The two main mining mechanisms of gas injection throughput and dissolution viscosity reduction divide the physical process of gas injection throughput of the volume fracturing oil reservoir into a gas injection supplementary energy stage, a well closing dissolution viscosity reduction stage and a well opening production three-phase flow stage. The first stage is a gas injection energy supplementing stage, because the permeability of a main fracture area and a volume modification area is higher, injected gas firstly enters a fracture and then rapidly enters the volume modification area through the fracture, because the gas diffusion speed is high, the gas can be assumed to be uniformly distributed in a control volume, meanwhile, because the permeability of an unmodified area is extremely low, the model assumes that the injected gas exists in the volume modification area and does not enter the unmodified area, but pressure conduction can exist between the volume modification area and the unmodified area, as shown in fig. 2; the second stage is a stuffy well dissolution and viscosity reduction stage, which stops gas injection and reforms CO in the area ₂ Gradually dissolve in crude oil to become dissolved gas, which causes the property and saturation of crude oil to change, and at the same time, a part of CO is remained ₂ Is not dissolved in crude oil and is free CO ₂ The state exists in the reforming zone, as shown in fig. 3; the third phase is a three-phase flow phase of open-hole recovery, the well is closed, the open-hole recovery is finished, fluid is firstly extracted from a main fracture flowing into a shaft, then fluid in a modified volume begins to flow into a main fracture area, and finally the formation pressure in a modified area is reduced, and fluid in an unmodified area also begins to flow into the modified area, as shown in fig. 4.

Example 1

The first embodiment of the invention provides a method for predicting the throughput exploitation capacity of carbon dioxide, the flow of which is shown in fig. 5, comprising the following steps:

step S51: after the carbon dioxide is injected in a huff-puff manner, the water content, the oil content and the gas content saturation and the formation pressure of the reforming region are updated according to the carbon dioxide injection amount, the volume of cracks in the oil reservoir reforming region, the volume of the reforming region, the original formation pressure, the water content saturation, the oil content saturation and the porosity.

Assuming that the fluid injection process is instantaneously completed, the gas diffusion rate is high, and the gas is considered to be uniformly distributed in the control volume and the reconstruction area, and the model considers the viscosity reduction effect caused by carbon dioxide dissolution or miscibility. Referring to FIG. 6, the formation physical field update after gas injection and energy replenishment comprises the steps of:

Step S511: and determining the original water content and the oil content of the reforming region before the carbon dioxide huff-puff injection according to the volume of the reforming region, the original water saturation, the oil saturation and the porosity.

The original water and oil content of the retrofit zone prior to carbon dioxide huff and puff injection can be determined by the following equations (1) and (2), respectively:

in the formulas (1) and (2), W _i And N _i The original water content and the oil content of the reforming zone are respectively V _t To modify the area volume phi _i In order to reform the original porosity of the region,and->The saturation of original water and oil in the reforming zone respectively, B _w And B _o The volume coefficients of the water phase and the oil phase are respectively.

Step S512: and updating the water content, oil content and gas saturation of the reforming zone according to the carbon dioxide injection amount and the original water content and oil content of the reforming zone.

The water, oil and gas saturation of the reforming zone can be updated according to the carbon dioxide injection amount and the original water and oil contents of the reforming zone by the following formulas (3) - (5), respectively:

in the formulas (3) to (5),and->Respectively the water saturation, the oil saturation and the gas saturation of the updated reforming zone, W _i And N _i The original water content and the oil content of the reforming zone are respectively B _w 、B _o And B _g Volume coefficients of water phase, oil phase and gas phase respectively, V _{injg_sc} Is the surface volume for carbon dioxide injection.

Step S513: and updating the formation pressure of the reforming region according to the carbon dioxide injection quantity, the crack volume in the reforming region, the volume of the reforming region, the original formation pressure, the porosity and the updated water, oil and gas saturation.

The formation pressure of the retrofit region may be updated by the following equation (6):

in the formula (6) of the present invention,for updated formation pressure, p ₀ To reform the original formation pressure of the zone c _w 、c _o 、c _g 、c _F And c _r Compression coefficients of cracks and matrixes in water phase, oil phase, gas phase and reforming zone respectively, +.> And->Respectively updated water content, oil content and gas saturation, V _t To reform the volume of the region, V _F To reform the volume of the fracture in the zone _i To reform the original porosity of the region B _g Is the volume coefficient of the gas phase.

Further, the above formula (6) can be derived by the following procedure:

after injection of the gas, the subsurface volume of the injected gas V _inj Equal to the volume compression DeltaV of the underground oil _o Volume compression of groundwater DeltaV _w Volume compression of subsurface gas DeltaV _g Increase in pore volume DeltaV _p The sum of the four, namely:

V _inj ＝ΔV _o +ΔV _w +ΔV _p +ΔV _g (7)

wherein,

V _inj ＝V _{injg_sc} B _g (8)

in the formula (8), B _g Is the volumetric coefficient of the gas.

ΔV _w ＝c _w V _t φ _i S _w (p _a -p _i ) (9)

In the formula (9), c _e Is the compression coefficient of water, V _t Is the volume of the transformation area phi _i For the average porosity of the reservoir in the original state (which needs to be weighted by different fracture network reservoir characteristics), S _w Is water saturation，p _a For average formation pressure at end of injection, p _i Is the original formation pressure.

Since it is assumed that the fluid injection process is completed instantaneously, it can be considered that the gas has not yet started to dissolve after the injection is completed, then:

ΔV _o ＝c _o V _t φ _i S _o (p _a -p _i ) (10)

in the formula (10), c _o Is the compression coefficient of oil, S _o Is oil saturation.

ΔV _p ＝[c _F V _F +c _r (V _t -V _F )](p _a -p _i ) (11)

In the formula (11), c _F Is the compression coefficient of the fracture medium, c _r Compression coefficient of matrix rock, V _F Is the fracture volume.

ΔV _g ＝c _g V _t φ _i S _g (p _a -p _i ) (12)

In the formula (12), c _g Is the compression coefficient of the gas, S _g For injection of undissolved carbon dioxide saturation in the gas pre-oil layer.

Since the gas is not dissolved after the injection is completed, the average pressure of the stratum after the injected gas is obtained by substituting the formulas (8) - (12) into the formula (7) is as follows:

step S52: in the well closing stage, the following steps are executed according to a first set interval: and determining the solubility of the carbon dioxide in the crude oil according to the current stratum pressure and temperature, updating the current water, oil and gas saturation according to the solubility, the current oil saturation and the carbon dioxide injection amount until the well closing stage is finished, and determining the current viscosity of the crude oil according to the current solubility and the oil saturation.

Taking the dissolution characteristic of carbon dioxide into consideration, part of the carbon dioxide is gradually dissolved into the crude oil during the well closing process and reduces the viscosity of the crude oil. Final resultA portion of the carbon dioxide is dissolved in the crude oil and another portion is stored as free gas in the pores of the porous medium. The solubility of carbon dioxide in crude oil is defined as the volume of gas dissolved in a unit volume of crude oil, expressed in Gc, in m, at a certain temperature ³ /m ³ . The solubility is mainly related to crude oil properties, pressure and temperature, and is specifically determined by using indoor experiments, and the following formula is given as reference:

G _c ＝-56.63+3.227T+14.83p-0.05476T ² -0.3718Tp+1.207p ² +0.0003T ³ +0.002803T ² p-0.006063Tp ² -0.03827p ³ (14)

in formula (14), T is temperature in degrees Celsius; p is pressure, the unit is Mpa, and the formation pressure of the reforming area is not changed in the process of well closing, namely the formation pressure is consistent with the pressure before well closing after the huff and puff injection of carbon dioxide; the constants in equation (14) are experimental fitting values, which is only an example, and the fitting values of the constants may change as well after the crude oil properties change or other relevant conditions change.

The current water, oil and gas saturation can be further updated by formulas (15) - (17) based on the current determined solubility, current oil saturation and carbon dioxide injection amount:

in the formulas (15) to (17), And->Respectively updated water content, oil content and gas saturation, W _i And N _i The original water content and oil content of the reforming zone are respectively +.> And->The saturation of original water and oil in the reforming zone respectively, B _w 、B _o And B _g Volume coefficients of water phase, oil phase and gas phase respectively, V _{injg_sc} For injecting carbon dioxide into the ground volume, S _o G is the current saturation of oil _c Is the current solubility of carbon dioxide in crude oil.

After the completion of the well-tie phase, the current crude oil viscosity may be updated by the following steps, see fig. 7:

step S71: the mole fraction of carbon dioxide in the crude oil is determined based on the current solubility and oil saturation.

The mole fraction of carbon dioxide in crude oil is determined from the current solubility and oil saturation by the following equation (18):

in the formula (18), x _i Is the mole fraction of carbon dioxide in the crude oil; g _c Is the solubility of carbon dioxide in crude oil at present;is the current oil saturation; v (V) _m Is the molar volume of gas, mol/L; m is M _o Is the average molecular weight of crude oil, g/mol; ρ _o Is the density of crude oil; v (V) _t Is the volume of the reconstruction area; phi (phi) _i To reform the original porosity of the region. V removal _m And M _o Other parameters are used in international units.

Step S72: the current crude oil viscosity is determined based on the mole fraction of carbon dioxide in the crude oil and the current temperature.

Determining the current crude oil viscosity from the mole fraction of carbon dioxide in the crude oil and the current temperature by equation (19):

lnμ _o ＝(1-x _i )lnμ _T +x _i (lnμ _c +a+b ln T) (19)

in the formula (19), μ _o For the current crude oil viscosity x _i Is the mole fraction of carbon dioxide in crude oil, T is the current temperature, mu _T Is the viscosity of crude oil at temperature T without carbon dioxide, mu _c Mu, the viscosity of the carbon dioxide at the current temperature _o 、μ _T Sum mu _c The units of (a) are mPas; a. b is the influence coefficient, which can be found from experimental data, where a=14.5, b= -1.8 is desirable. The first term on the right side of the formula means the effect of heat viscosity reduction on the final crude oil viscosity, the second term means the effect of carbon dioxide viscosity on the final crude oil viscosity, and the term b ln T means that the viscosity reduction effect of carbon dioxide is affected by temperature.

The viscosity of carbon dioxide can be calculated according to the gas manual by the formula:

u _c ＝10 ^-4 ·(11.336+4.9918×10 ^-01 (T+273.15)-1.0876×10 ^-04 (T+273.15) ² ) (20)。

step S53: in the production stage of open well, the following steps are executed according to a second set interval: according to the current crude oil viscosity, the solubility of carbon dioxide in the crude oil and the relative permeability of each phase under the current saturation condition, carrying out multiphase splitting on the current yield determined by the five-zone linear abortion energy model to obtain each phase yield, obtaining the accumulated yield of each phase after well production, and updating the current water, oil and gas saturation according to the accumulated yield of each phase and the current oil saturation.

Specifically, the current yield determined by the five-zone linear abortion energy model can be subjected to multiphase splitting according to the following formulas (21) - (23) to obtain the current water phase, oil phase and gas phase yields:

in the formulas (21) - (23), q _t For determining the current yield of the five-zone linear abortion energy model, it is to be noted that the unmodified zone of the five-zone linear abortion energy model is divided into three parts, and in this embodiment, one unmodified zone, namely the third zone, represents three unmodified zones of the five-zone productivity model, so as to simplify the gas injection throughput productivity deducing process and not influence the productivity calculation; q _w 、q _o And q _g Current capacity for water phase, oil phase and gas phase respectively; k (k) _rw 、k _ro And k _rg The relative permeabilities of the water phase, the oil phase and the gas phase under the current saturation condition can be obtained through experiments; mu (mu) _o Mu, the current crude oil viscosity _w Sum mu _g Viscosity of aqueous phase and gas phase, respectively, B _w 、B _o And B _g Volume coefficients of water phase, oil phase and gas phase respectively, G _c Is the current solubility of carbon dioxide in crude oil.

Further, based on the cumulative yield of each phase and the current saturation of oil, the current saturation of water, oil, and gas can be updated by the following formulas (24) - (26):

in the formulas (24) - (26),and->Respectively updated water content, oil content and gas saturation, S _o For the current saturation of oil, W _p 、N _p And G _p Cumulative yields of aqueous, oil and gas phases, respectively, B _w 、B _o And B _g Volume coefficients of water phase, oil phase and gas phase respectively, G _c V is the solubility of carbon dioxide in crude oil _t Phi is the volume of the reforming zone _i To the original porosity of the modified zone, V _{injg_sc} For injecting carbon dioxide into the ground volume, W _i And N _i The original water content and the oil content of the reforming region are respectively +.> And->And the saturation degree of original water and oil in the reforming region is respectively set.

In some embodiments, updating the current water, oil, and gas saturation based on the cumulative production of each phase and the current oil saturation may further comprise:

and updating the formation pressure according to the accumulated output of each phase and the updated water, oil and gas saturation.

Specifically, the formation pressure is updated according to the cumulative production of each phase and the updated water, oil and gas saturation, using the following equation (27):

in the formula (27) of the present invention,for updated formation pressure, p is the current formation pressure, c _w 、c _o 、c _g 、c _F And c _r Respectively water phase, oil phase, gas phase, compression coefficient of crack and matrix in the transformation zone, V _F Is the volume of the fracture in the modified zone.

The above formula (27) can be derived by the following procedure:

After the well is opened, the stratum fluid is continuously extracted from the stratum, so that the stratum pressure and the reservoir fluid saturation are continuously changed, and the reservoir physical field in the production process is continuously updated according to the calculation step length during calculation. The formation pressure after well opening can still be calculated by the principle of volume balance, namely the underground volume of the produced fluid is equal to the expansion of underground crude oil, the expansion of underground water, the expansion of underground gas and the reduction of pore volume:

V _pro ＝ΔV _o +ΔV _w +ΔV _p +ΔV _g (28)

wherein V is _pro ＝N _p B _o +W _p B _w (29)

In the formula (29), N _p For accumulated oil production after well opening, W _p Is accumulated water after well opening.

In the formula (30) of the present invention,φ _t for the average oil saturation and porosity of the different production stages, +.>Is the average pressure after the well is opened.

In the formula (31) of the present invention,is the average water saturation of the different production stages.

In the formula (32) of the present invention,is the average gas saturation of different production stages.

Substituting formulas (29) - (33) into formula (28) to obtain the average formation pressure at any time after the well is opened, wherein the average formation pressure is as follows:

according to the carbon dioxide throughput exploitation productivity prediction method provided by the embodiment of the invention, from the gas injection throughput mechanism, CO is considered ₂ The gas injection throughput is divided into a gas injection supplementary energy stage, a well-closed dissolution viscosity reduction stage and a well-open stope three-phase flow stage by the supplementary energy and dissolution viscosity reduction mechanism, pressure and saturation change equations of the three stages are respectively deduced, and a horizontal well volume fracturing five-zone linear abortion energy model is combined to deduce CO ₂ Throughput capacity equation.

Currently available for CO research ₂ Throughput-based applications, e.g. Intersect, eclipse, etc. large-scaleThe commercial numerical simulation software adopts a numerical calculation method, is high in cost, high in running environment requirement, large in required data volume and long in research time. The carbon dioxide huff and puff exploitation productivity prediction method provided by the embodiment of the invention adopts CO injection aiming at unconventional oil reservoirs ₂ The throughput supplementing energy development mode adopts an analysis method to evaluate the oil well production energy, and has the advantages of strong pertinence, low use cost, high running speed and convenient use compared with large-scale numerical simulation software; can evaluate different types of unconventional oil reservoirs CO ₂ Throughput capacity, simple, fast and efficient calculation method, and is more suitable for fast evaluation and comparison of on-site unconventional oil reservoir development modes and establishment of development technical policies; the amount of the resources of the covered unconventional oil reservoir reaches hundreds of billions of tons, and the application prospect is wide.

The typical well in the G test area is selected as an example to compare the calculation results of the gas injection throughput numerical simulation method and the model analysis method (the model method in the first embodiment), the numerical simulation calculation adopts the Eclipse numerical simulation software which is common at present, the main parameters adopted by the model are shown in table 1, and the gas injection throughput horizontal well yield and the formation pressure comparison result are shown in fig. 8 and 9.

TABLE 1 main parameter table for verifying gas injection throughput capacity prediction model

Reservoir width, m	500	Cluster spacing, m	15
				Reservoir thickness, m	12.5	Matrix permeability, mD	0.01
Fracture permeability, mD	1000	Rock compression coefficient, MPa -1	6e -4
				Porosity of the matrix	8％	Crack porosity	1％
Formation pressure, MPa	40	Half length of split seam, m	100
				Number of fracturing segments and number of clusters	20 segments 60 clusters	Viscosity of crude oil, mPas	10.0

The comparison scheme adopts a model analysis method and a numerical simulation method to calculate the failure exploitation after horizontal volume fracturing, and adopts CO ₂ The gas injection throughput supplements formation energy production and formation pressure for a total of three cycles. Stopping mining and transferring injection for 6 years after horizontal well volume fracturing failure, and injecting 3 kilotons of CO in a cumulative way for 1 month after gas injection ₂ Afterwards, the well is closed for one month, and then the next round of huff and puff is carried out after 22 months of well opening and stoping. The gas injection throughput is 3 cycles, and CO is injected ₂ Under the condition of keeping the same working system, the highest yield of the horizontal well is gradually reduced by 9 kilotons, and the comparison curve of the yield of the horizontal well and the formation pressure calculated by a numerical method and an analytical method can be seen, wherein the calculation results of the two are similar, and the error is causedWithin 5%, the gas injection throughput analysis model of the embodiment has higher prediction and development index precision, and can be used for research works such as evaluation of unconventional oil reservoir volume fracturing gas injection throughput development effect, development technical policy formulation and the like.

The above technical solution is as shown in fig. 10, considering CO from the gas injection throughput mechanism ₂ Supplementary energy mechanism and dissolution viscosity reduction mechanism of gas injection throughput. Dividing the gas injection throughput into a gas injection supplementary energy stage, a well closing dissolution viscosity reduction stage and a well opening stoping three-phase flow stage on the physical process division, respectively deducing pressure and saturation change equations of the three stages, and deducing CO by considering a volume fracturing horizontal well as a main fracture zone, a modified zone and an unmodified zone ₂ Throughput capacity equation, further calculate CO according to the capacity equation ₂ Multiple times of gas injection, throughput recovery and on-site CO formation ₂ The rapid evaluation model of the gas injection throughput development effect is used for predicting multiphase productivity and acquiring saturation data of each stage.

Example two

The second embodiment of the invention provides a specific implementation flow of a carbon dioxide huff and puff exploitation productivity prediction method, wherein the model established in the first embodiment is applied to shale oil of a reed canary group of xx oil fields, the shale oil of the reed canary group can be longitudinally divided into an upper dessert and a lower dessert, the dominant lithology of the upper dessert is rock debris feldspar powder fine sandstone, and the dominant lithology of the lower dessert is cloud fine siltstone. The lower dessert plane distribution is stable, the whole longitudinal reservoir layer thickness is 10-15 m, the average permeability of the reservoir layer is 0.009mD, the viscosity of crude oil at 50 ℃ is 94.20-407.08 mPa.s, the average viscosity is 123.23mPa.s, the viscosity of crude oil in stratum is 6-40 mPa.s, the average viscosity is 21mpa.s, and the method is used for rapidly evaluating CO ₂ The gas injection throughput improves the single well yield and the recovery efficiency, and different COs are predicted by adopting the productivity equation software ₂ The method comprises the steps of designing four injection quantity calculation examples respectively for accumulating oil production and recovery ratio of a single well under injection quantity, wherein each calculation example is three in throughput, and CO is injected respectively in each round ₂ The amounts of the catalyst are 1000 tons, 2000 tons, 3000 tons, 4000 tons and 5000 tons, and the CO is injected respectively by accumulating three rounds ₂ For 3000 tons, 6000 tons, 9000 tons, 12000 tons and 15000 tons, 20 years of level is calculatedThe cumulative oil production of the wells is 27715 square, 30936 square, 35383 square, 39903 square and 42696 square respectively, the comparison curves of the yields are shown in figure 11, the calculated recovery rates are respectively 7.9%, 8.8%, 10.1%, 11.4% and 12.2%, and are respectively 0.3%, 1.2%, 2.5%, 3.8% and 4.6% higher than those of the failure recovery, and the CO is visible ₂ The higher the injection at throughput, the greater the recovery enhancement, but when CO is in a single pass ₂ After the throughput injection capacity exceeds 4000 tons, the increase amplitude of the output and the final recovery ratio of the horizontal well is reduced under the same injection increment, the economic benefit is relatively poor, and single-round CO is optimized ₂ The injection amount is 3000-4000 tons. The method can effectively compare different COs ₂ Throughput capacity, CO prediction ₂ The throughput improves the recovery ratio amplitude and can optimize CO ₂ Developing technical policies such as injection quantity, injection speed and the like, namely CO ₂ The preference of throughput schemes and the determination of technical parameters provide important research tools.

In addition, the model is suitable for different types of compact oil and shale oil, and the difference of different unconventional oil reservoirs is mainly reflected in main geological characteristic parameters, permeability curves and CO of the oil reservoirs ₂ Dissolution equation, etc. The patent analytic model can adjust input data according to the parameters of each oil reservoir to obtain CO under each oil reservoir type ₂ And the throughput result prediction is simple, convenient and efficient. Unconventional resources become the main body of the current and subsequent capacity construction of Chinese petroleum, horizontal well volume fracturing becomes the current main body construction technology, but almost all horizontal wells currently adopt a failure exploitation mode after volume fracturing, and the problems of energy supplementing and recovery ratio improvement are faced, and CO ₂ Throughput has proven to be an economical and effective way of supplementing energy development, and the patent will be unconventional oil reservoir CO ₂ The throughput capacity evaluation provides a convenient and reliable analysis model, and has wide application prospect.

Based on the inventive concept of the present invention, an embodiment of the present invention further provides a device for predicting productivity of carbon dioxide throughput exploitation, where the structure of the device is shown in fig. 12, and the device includes:

A physical field updating module 121 after carbon dioxide huff and puff injection, configured to update the water content, the oil content, the gas content saturation and the formation pressure of the reforming region according to the carbon dioxide injection amount, the fracture volume in the oil reservoir reforming region, the volume of the reforming region, the original formation pressure, the water saturation, the oil content saturation and the porosity after the carbon dioxide huff and puff injection;

the well-closing stage physical field updating module 122 is configured to perform the following steps at a first set interval in the well-closing stage: determining the solubility of carbon dioxide in crude oil according to the current stratum pressure and temperature, updating the current water, oil and gas saturation according to the solubility, the current oil saturation and the carbon dioxide injection amount until the well closing stage is finished, and determining the current crude oil viscosity according to the current solubility and the oil saturation;

the physical field updating and productivity predicting module 123 of the open production stage is configured to perform the following steps according to the second set interval in the open production stage: according to the current crude oil viscosity, the solubility of carbon dioxide in the crude oil and the relative permeability of each phase under the current saturation condition, carrying out multiphase splitting on the current yield determined by the five-zone linear abortion energy model to obtain each phase yield, obtaining the accumulated yield of each phase after well production, and updating the current water, oil and gas saturation according to the accumulated yield of each phase and the current oil saturation.

The specific manner in which the various modules perform the operations in the apparatus of the above embodiments have been described in detail in connection with the embodiments of the method, and will not be described in detail herein.

Based on the inventive concept, the embodiments of the present invention further provide a computer program product, including a computer program/instruction, where the computer program/instruction, when executed by a processor, implements the above-mentioned carbon dioxide throughput exploitation productivity prediction method.

Unless specifically stated otherwise, terms such as processing, computing, calculating, determining, displaying, or the like, may refer to an action and/or process of one or more processing or computing systems, or similar devices, that manipulates and transforms data represented as physical (e.g., electronic) quantities within the processing system's registers or memories into other data similarly represented as physical quantities within the processing system's memories, registers or other such information storage, transmission or display devices. Information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

It should be understood that the specific order or hierarchy of steps in the processes disclosed are examples of exemplary approaches. Based on design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged without departing from the scope of the present disclosure. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

In the foregoing detailed description, various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments of the subject matter require more features than are expressly recited in each claim. Rather, as the following claims reflect, invention lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate preferred embodiment of this invention.

Those of skill would further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. The processor and the storage medium may reside as discrete components in a user terminal.

For a software implementation, the techniques described herein may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. These software codes may be stored in memory units and executed by processors. The memory unit may be implemented within the processor or external to the processor, in which case it can be communicatively coupled to the processor via various means as is known in the art.

The foregoing description includes examples of one or more embodiments. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned embodiments, but one of ordinary skill in the art may recognize that many further combinations and permutations of various embodiments are possible. Accordingly, the embodiments described herein are intended to embrace all such alterations, modifications and variations that fall within the scope of the appended claims. Furthermore, as used in the specification or claims, the term "comprising" is intended to be inclusive in a manner similar to the term "comprising" as "comprising" is interpreted when employed as a transitional word in a claim. Furthermore, any use of the term "or" in the specification of the claims is intended to mean "non-exclusive or".

Claims (16)

1. A method for predicting throughput production capacity of carbon dioxide, comprising:

after the huff and puff injection of the carbon dioxide, the water content, the oil content, the gas content saturation and the formation pressure of the reforming region are updated according to the carbon dioxide injection amount, the volume of cracks in the oil reservoir reforming region, the volume of the reforming region, the original formation pressure, the water content saturation, the oil content saturation and the porosity;

In the well closing stage, the following steps are executed according to a first set interval: determining the solubility of carbon dioxide in crude oil according to the current stratum pressure and temperature, updating the current water, oil and gas saturation according to the solubility, the current oil saturation and the carbon dioxide injection amount until the well closing stage is finished, and determining the current crude oil viscosity according to the current solubility and the oil saturation;

in the production stage of open well, the following steps are executed according to a second set interval: according to the current crude oil viscosity, the solubility of carbon dioxide in the crude oil and the relative permeability of each phase under the current saturation condition, carrying out multiphase splitting on the current yield determined by the five-zone linear abortion energy model to obtain each phase yield, obtaining the accumulated yield of each phase after well production, and updating the current water, oil and gas saturation according to the accumulated yield of each phase and the current oil saturation.

2. The method according to claim 1, wherein the multiphase splitting of the current yield determined by the five-zone linear abortion energy model is performed to obtain each phase yield, and the method specifically comprises:

performing multiphase splitting on the current yield determined by the five-zone linear abortion energy model according to the following formulas (1) - (3) to obtain the current water phase, oil phase and gas phase productivity:

In the formulas (1) - (3), q _t Determining the current yield for the five-zone linear abortion energy model; q _w 、q _o And q _g Current capacity for water phase, oil phase and gas phase respectively; k (k) _rw 、k _ro And k _rg Relative permeabilities, μ, of aqueous, oil and gas phases, respectively, at current saturation conditions _o Mu, the current crude oil viscosity _w Sum mu _g Viscosity of aqueous phase and gas phase, respectively, B _w 、B _o And B _g Volume coefficients of water phase, oil phase and gas phase respectively, G _c Is the current solubility of carbon dioxide in crude oil.

3. The method of claim 1, wherein updating the current saturation of water, oil and gas based on the cumulative production of each phase and the current saturation of oil, specifically comprises:

updating the current water, oil and gas saturation according to the accumulated output of each phase and the current oil saturation by the following formulas (4) - (6):

in the formulas (4) to (6),and->Respectively updated water content, oil content and gas saturation, S _o For the current saturation of oil, W _p 、N _p And G _p Cumulative yields of aqueous, oil and gas phases, respectively, B _w 、B _o And B _g Volume coefficients of water phase, oil phase and gas phase respectively, G _c V is the solubility of carbon dioxide in crude oil _t Phi is the volume of the reforming zone _i To the original porosity of the modified zone, V _{injg_sc} For injecting carbon dioxide into the ground volume, W _i And N _i The original water content and the oil content of the reforming region are respectively +.> And->And the saturation degree of original water and oil in the reforming region is respectively set.

4. The method of claim 3, wherein updating the current saturation level of water, oil and gas based on the accumulated production of each phase and the current saturation level of oil, further comprises:

and updating the formation pressure according to the accumulated output of each phase and the updated water, oil and gas saturation.

5. The method of claim 4, wherein updating the formation pressure based on the cumulative production of each phase and the updated water, oil, and gas saturation levels, comprises:

updating formation pressure according to the accumulated output of each phase and the updated water, oil and gas saturation, by using the following formula (7):

in the formula (7) of the present invention,for updated formation pressure, p is the current formation pressure, c _w 、c _o 、c _g 、c _F And c _r Respectively water phase, oil phase, gas phase, compression coefficient of crack and matrix in the transformation zone, V _F Is the volume of the fracture in the modified zone.

6. The method of claim 1, wherein updating the water, oil and gas saturation and formation pressure of the reforming zone based on carbon dioxide injection, fracture volume in the reservoir reforming zone, volume of the reforming zone, original formation pressure, water saturation, oil saturation and porosity, comprises:

Determining the original water content and the oil content of the reforming region before carbon dioxide huff and puff injection according to the volume of the reforming region, the original water saturation, the oil saturation and the porosity;

updating the water content, oil content and gas saturation of the reforming region according to the carbon dioxide injection amount and the original water content and oil content of the reforming region;

and updating the formation pressure of the reconstruction zone according to the carbon dioxide injection quantity, the volume of the cracks in the reconstruction zone, the volume of the reconstruction zone, the original formation pressure, the porosity and the updated water, oil and gas saturation.

7. The method of claim 6, wherein said determining the raw water and oil content of said retrofit region prior to carbon dioxide throughput injection comprises:

the original water content and oil content of the reforming zone prior to carbon dioxide huff-puff injection are determined by the following formulas (8) and (9), respectively:

in formulas (8) and (9), W _i And N _i The original water content and the oil content of the reforming region are respectively V _t Phi is the volume of the reforming zone _i For the original porosity of the modified zone,and->Respectively the original water content and oil content saturation degree of the reforming region, B _w And B _o The volume coefficients of the water phase and the oil phase are respectively.

8. The method of claim 6, wherein said updating the water, oil and gas saturation of said retrofit zone based on the carbon dioxide injection and the original water, oil content of said retrofit zone, comprises:

updating the water content, the oil content and the gas saturation of the reforming zone according to the carbon dioxide injection amount and the original water content and the oil content of the reforming zone through the following formulas (10) - (12):

in the formulas (10) - (12),and->Respectively updated water content, oil content and gas saturation, W _i And N _i Respectively the original water content and the oil content of the reforming region, B _w 、B _o And B _g Volume coefficients of water phase, oil phase and gas phase respectively, V _{injg_sc} Is the surface volume for carbon dioxide injection.

9. The method of claim 6, wherein updating the formation pressure in the reforming zone based on carbon dioxide injection, the volume of the cracks in the reforming zone, the volume of the reforming zone, the original formation pressure, the porosity, and updated water, oil, and gas saturation, comprises:

updating the formation pressure of the reforming zone according to the carbon dioxide injection amount, the volume of the cracks in the reforming zone, the volume of the reforming zone, the original formation pressure, the porosity and the updated water, oil and gas saturation, by the following formula (13):

In the formula (13) of the present invention,for updated formation pressure, p ₀ Original formation pressure for the retrofit zone，c _w 、c _o 、c _g 、c _F And c _r Respectively an aqueous phase, an oil phase, a gas phase, the compressibility of the cracks and the matrix in the modified zone, +.>And->Respectively updated water content, oil content and gas saturation, V _t For the volume of the reforming zone, V _F Phi is the volume of the crack in the reforming zone _i To the original porosity of the modified zone, B _g Is the volume coefficient of the gas phase.

10. The method of claim 1, wherein updating the current water, oil and gas saturation according to the solubility, the current oil saturation and the carbon dioxide injection amount comprises:

based on the solubility, current oil saturation, and the carbon dioxide injection amount, the current water, oil, and gas saturation is updated by formulas (14) - (16):

in the formulas (14) - (16),and->Respectively updated water content, oil content and gas saturation, W _i And N _i The original water content, oil content, < > -of said modified zone respectively> V _t Phi is the volume of the reforming zone _i For the original porosity of the modified zone +.>And->Respectively the original water content and oil content saturation degree of the reforming region, B _w 、B _o And B _g Volume coefficients of water phase, oil phase and gas phase respectively, V _{injg_sc} For injecting carbon dioxide into the ground volume, S _o G is the current saturation of oil _c Is the current solubility of carbon dioxide in crude oil.

11. The method of claim 1, wherein determining the current crude oil viscosity based on the current solubility and oil saturation comprises:

determining the mole fraction of carbon dioxide in the crude oil based on the current solubility and the oil saturation;

the current crude oil viscosity is determined based on the mole fraction of carbon dioxide in the crude oil and the current temperature.

12. The method of claim 11, wherein determining the mole fraction of carbon dioxide in the crude oil based on the current solubility and oil saturation comprises:

the mole fraction of carbon dioxide in crude oil is determined from the current solubility and oil saturation by the following equation (17):

in the formula (17), x _i G is the mole fraction of carbon dioxide in crude oil _c For the current solubility of carbon dioxide in crude oil,for the current saturation of oil, V _m M is the molar volume of the gas _o Is the average molecular weight of crude oil ρ _o Is the density of crude oil, V _t Phi is the volume of the reforming zone _i Original porosity for the modified zone.

13. The method of claim 11, wherein determining the current crude oil viscosity based on the mole fraction of carbon dioxide in the crude oil and the current temperature, comprises:

Determining the current crude oil viscosity from the mole fraction of carbon dioxide in the crude oil and the current temperature by equation (18):

lnμ _o ＝(1-x _i )lnμ _T +x _i (lnμ _c +a+blnT) (18)

in the formula (18), μ _o For the current crude oil viscosity x _i Is the mole fraction of carbon dioxide in crude oil, T is the current temperature, mu _T Is the viscosity of crude oil at temperature T without carbon dioxide, mu _c The viscosity of carbon dioxide at the current temperature is represented by a and b, which are influence coefficients.

14. The method of any one of claims 1-13, further comprising:

and dividing the oil reservoir after the volume fracturing into three areas, namely a main fracture area, the modified area and an unmodified area.

15. A carbon dioxide huff and puff production capacity prediction device, comprising:

the physical field updating module after the carbon dioxide huff and puff injection is used for updating the water content, the oil content, the gas content saturation and the formation pressure of the reforming region according to the carbon dioxide injection quantity, the crack volume in the oil reservoir reforming region, the volume of the reforming region, the original formation pressure, the water saturation, the oil content saturation and the porosity after the carbon dioxide huff and puff injection;

the physical field updating module in the well closing stage is used for executing the following steps according to a first set interval in the well closing stage: determining the solubility of carbon dioxide in crude oil according to the current stratum pressure and temperature, updating the current water, oil and gas saturation according to the solubility, the current oil saturation and the carbon dioxide injection amount until the well closing stage is finished, and determining the current crude oil viscosity according to the current solubility and the oil saturation;

The physical field updating and each-phase productivity predicting module is used for executing the following steps according to a second set interval in the well opening production stage: according to the current crude oil viscosity, the solubility of carbon dioxide in the crude oil and the relative permeability of each phase under the current saturation condition, carrying out multiphase splitting on the current yield determined by the five-zone linear abortion energy model to obtain each phase yield, obtaining the accumulated yield of each phase after well production, and updating the current water, oil and gas saturation according to the accumulated yield of each phase and the current oil saturation.

16. A computer program product comprising computer programs/instructions which when executed by a processor implement the carbon dioxide throughput production capacity prediction method of any one of claims 1 to 14.