Method and device for determining dynamic control reserves of abnormal high pressure gas reservoir, equipment and medium

Abstract

The application provides an abnormal high-pressure gas reservoir dynamic control reserve determination method, device, equipment and medium. The method comprises the following steps: determining the parameters of the gas reservoir where the gas well is located and the rock compressibility quantization index of the reservoir; determining the pseudo-pressure of the gas well according to the parameters of the gas reservoir where the gas well is located; obtaining a target coefficient according to the natural gas viscosity, the natural gas isothermal compressibility coefficient, the pseudo-pressure and the rock compressibility quantization index of the reservoir; determining the decline index of the gas well in the hyperbolic window stage according to the target coefficient and the pseudo-pressure of the gas well; determining the natural gas production variable and the cumulative gas production variable according to the decline index of the gas well in the hyperbolic window stage; and determining the dynamic geological reserve of the gas well according to the natural gas production variable and the cumulative gas production variable. The method provided by the application reduces the operation cost and difficulty and improves the calculation accuracy.

Description

Technical Field

[0001] This application relates to the field of oil and gas exploration and development technology, and in particular to methods, devices, equipment and media for determining the dynamic control reserves of abnormally high-pressure gas reservoirs. Background Technology

[0002] Gas reservoir reserves refer to the original geological reserves of a gas reservoir under natural conditions, and are usually described by parameters such as the reservoir's geometry, area, height, and reservoir properties. Calculating gas reservoir reserves is of great significance for gas reservoir development.

[0003] Current technologies for calculating the dynamic reserves of abnormally high-pressure gas reservoirs typically employ three methods: mass balance, traditional production decline analysis, and empirical formulas. The mass balance method, based on the law of conservation of mass, calculates reserves by combining gas reservoir production and pressure data. This method is suitable for gas reservoirs with a history of continuous pressure decline and requires sufficient dynamic data. Traditional production decline analysis uses the Arps decline equation for solution. With the accumulation of dynamic data on oil and gas reservoir development, modern decline analysis methods use Fetkovich, Blasingame, and AG production decline curves to fit actual production data and predict gas reservoir reserves. Empirical formulas typically establish reserve calculation formulas based on known gas reservoir data and experience, and are suitable for gas reservoirs with similar geological and engineering conditions.

[0004] However, existing technologies suffer from significant errors and high operational difficulty in implementation. Summary of the Invention

[0005] This application provides a method, apparatus, equipment, and medium for determining the reserves of abnormally high-pressure gas reservoirs through dynamic control, in order to solve the problems of large errors and high operating costs in the implementation of existing technologies.

[0006] Firstly, this application provides a method for determining the dynamic control reserves of abnormally high-pressure gas reservoirs, including:

[0007] Determine the parameters of the gas reservoir where the gas well is located, and the quantitative index of rock compressibility of the reservoir;

[0008] Determine the pseudo-pressure of the gas well based on the parameters of the gas reservoir where the gas well is located;

[0009] The target coefficient is obtained based on the gas viscosity, isothermal compressibility coefficient, pseudo-pressure, and reservoir rock compressibility quantification index of the gas well.

[0010] Based on the target coefficient and the pseudo-pressure of the gas well, determine the decline index of the gas well in the hyperbolic window stage;

[0011] The dynamic geological reserves of gas wells are determined based on natural gas production variables and cumulative gas production variables.

[0012] In this application, the pseudo-pressure of the gas well is determined based on the parameters of the gas reservoir where the gas well is located, including;

[0013] Based on the parameters of the gas reservoir where the gas well is located, determine the natural gas viscosity, natural gas isothermal compressibility coefficient, and natural gas deviation factor of the gas well;

[0014] The simulated pressure of the gas well is determined based on the parameters of the gas reservoir, the viscosity of the natural gas, and the natural gas deviation factor.

[0015] In this application, the target coefficients are obtained based on the gas viscosity, isothermal compressibility coefficient, pseudo-pressure, and reservoir rock compressibility quantification index of the gas well, including:

[0016] The first ratio coefficient is determined based on the gas viscosity of the gas well, the isothermal compressibility coefficient of the gas well, and the quantitative index of rock compressibility of the reservoir.

[0017] Based on the first ratio coefficient and the pseudo-pressure of the gas well, determine the target coordinate point in the double logarithmic coordinate system;

[0018] Determine the target coefficients based on the target coordinates in the double logarithmic coordinate system.

[0019] In this application, natural gas production variables and cumulative gas production variables are determined based on the decline index of the gas well during the hyperbolic window stage, including:

[0020] Determine the natural gas production and cumulative gas production of the gas well under standard conditions;

[0021] The natural gas production variable is determined based on the natural gas production of the gas well under standard conditions and the decline index of the gas well during the hyperbolic window phase.

[0022] The cumulative gas production variable is determined based on the cumulative gas production of the gas well, the decline index during the hyperbolic window stage, the viscosity of natural gas, the isothermal compressibility coefficient of natural gas, and the pseudo-pressure.

[0023] In this application, the dynamic geological reserves of a gas well are determined based on natural gas production variables and cumulative gas production variables, including:

[0024] A dynamic gas reservoir reserve model is generated based on natural gas production variables and cumulative gas production variables.

[0025] Based on the dynamic reserve model of the gas reservoir, the dynamic geological reserves of the gas well are determined.

[0026] In this application, a dynamic gas reservoir reserve model is generated based on natural gas production variables and cumulative gas production variables. The dynamic gas reservoir reserve model is as follows:

[0027]

[0028] For the natural gas production variable in the dynamic reserves model of gas reservoirs, For the gas reservoir dynamic reserve model, the cumulative gas production variable is denoted as , where This represents the natural gas production of a gas well under standard conditions. G represents the initial natural gas production, and G represents the dynamic geological reserves of the gas reservoir. It is a constant value. The gas density under initial conditions, The viscosity of natural gas under initial conditions. The isothermal compressibility coefficient of natural gas under initial conditions. This is the pseudo-pressure corresponding to the original formation pressure. The pseudo-pressure is the bottom hole flowing pressure. The quantitative index of rock compressibility under initial conditions. This represents the decreasing index of a gas well during the hyperbolic window phase. This represents the cumulative gas production of the gas well.

[0029] In this application, the dynamic geological reserves of gas wells are determined based on a dynamic gas reservoir reserve model, including:

[0030] Determine the target natural gas production variable, where the target natural gas production variable represents a natural gas production variable of 0;

[0031] Based on the target natural gas production variables and the dynamic reserve model of the gas reservoir, the dynamic geological reserves of the gas well are determined.

[0032] Secondly, this application provides a device for dynamically controlling and determining reserves in abnormally high-pressure gas reservoirs, comprising:

[0033] The determination module is used to determine the parameters of the gas reservoir where the gas well is located and the quantitative index of rock compressibility of the reservoir.

[0034] The first calculation module is used to determine the pseudo pressure of the gas well based on the parameters of the gas reservoir where the gas well is located;

[0035] The second calculation module is used to obtain the target coefficient based on the gas viscosity, isothermal compressibility coefficient, pseudo-pressure, and reservoir rock compressibility quantification index of the gas well.

[0036] The third calculation module is used to determine the decline index of the gas well in the hyperbolic window stage based on the target coefficient and the pseudo pressure of the gas well.

[0037] The fourth calculation module is used to determine the natural gas production variable and the cumulative gas production variable based on the decline index of the gas well in the hyperbolic window stage;

[0038] The execution module is used to determine the dynamic geological reserves of a gas well based on natural gas production variables and cumulative gas production variables.

[0039] Thirdly, this application provides an electronic device, including: a processor and a memory communicatively connected to the processor;

[0040] The memory stores instructions that the computer executes;

[0041] The processor executes computer execution instructions stored in memory to implement the method of this application.

[0042] Fourthly, this application provides a computer-readable storage medium, comprising: computer-executable instructions stored in the computer-readable storage medium, which, when executed by a processor, are used to implement the method of this application.

[0043] The method, apparatus, equipment, and medium for determining the dynamic control reserves of abnormally high-pressure gas reservoirs provided in this application determine the parameters of the gas reservoir where the gas well is located and the quantification index of the reservoir's rock compressibility; determine the pseudo-pressure of the gas well based on the parameters of the gas reservoir; obtain the target coefficient based on the gas well's natural gas viscosity, natural gas isothermal compressibility coefficient, pseudo-pressure, and the quantification index of the reservoir's rock compressibility; determine the decline index of the gas well in the hyperbolic window stage based on the target coefficient and the pseudo-pressure of the gas well; determine the natural gas production variable and cumulative gas production variable based on the decline index of the gas well in the hyperbolic window stage; and determine the dynamic geological reserves of the gas well based on the natural gas production variable and cumulative gas production variable. By calculating the gas well decline index in the early stage of the boundary control flow, i.e., the hyperbolic window stage, and combining it with the cumulative gas production variable and natural gas production variable, a dynamic reserve model of the gas reservoir is obtained. Based on the dynamic reserve model of the gas reservoir, the dynamic geological production of the abnormally high-pressure gas reservoir is determined. This avoids the problem of multiple iterations required by existing technologies, involves less complex data, and has a simple acquisition method, reducing the difficulty of operation. Attached Figure Description

[0044] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0045] Figure 1 A schematic diagram illustrating a scenario for the dynamic control method for determining reserves in abnormally high-pressure gas reservoirs provided in this application embodiment;

[0046] Figure 2 A flowchart illustrating the method for determining the dynamic control reserves of abnormal high-pressure gas reservoirs provided in this application embodiment;

[0047] Figure 3 A flowchart illustrating another method for determining the dynamic control reserves of abnormal high-pressure gas reservoirs provided in this application embodiment;

[0048] Figure 4A graph showing the variable relationships in the dynamic gas reservoir reserve model provided in this application embodiment;

[0049] Figure 5 A schematic diagram of the structure of the device for determining the reserves of abnormal high-pressure gas reservoirs under dynamic control provided in an embodiment of this application;

[0050] Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0051] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0052] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0053] Gas reservoir reserve calculation is a crucial component of gas reservoir engineering, primarily aimed at predicting and assessing the reservoir's potential. Commonly used methods for gas reservoir reserve calculation include the mass balance method, production decline analysis, and empirical formula methods. The mass balance method requires only two or more shut-in pressure tests to calculate dynamic reserves, and the calculation process is quite easy to operate, making it widely used. This method is often used in the early stages of development due to its simplicity and ease of operation. However, because obtaining formation pressure is relatively difficult, iterative methods are typically employed: that is, first assuming a... Value (original gas reservoir geological reserves), based on each Calculate the ratio of the mean formation pressure of the gas reservoir to the gas deviation factor under the mean pressure, then plot the results to obtain the calculated value. The calculated value is compared with the previously assumed value; if the difference is too large, the value is replaced. This process continues until the assumed value and the calculated value are close, at which point the iteration stops. The traditional method of production decline analysis uses the Arps decline equation for solution, requiring the collection of reservoir pressure and production data and the determination of the initial production rate. The method involves fitting actual gas reservoir production data into an equation using a decline coefficient to obtain the best-fit curve, and then predicting future gas reservoir production based on the fitted curve. However, the decline index is not constant in actual production, leading to significant errors in application and allowing it to serve only as a rough estimate. Modern production decline analysis first collects actual gas reservoir production data, including pressure, temperature, and production figures. Then, a suitable decline curve is selected for fitting to determine the dynamic characteristics and parameters of the gas reservoir. Finally, the future gas reservoir production and development effectiveness are predicted based on the fitting results, thereby assessing the reservoir's reserves. Commonly used decline curves include the Fetkovich production decline curve, the Blasingame production decline curve, and the AG production decline curve. This method, due to the subjectivity of manual fitting, inevitably contains errors. The empirical formula method establishes a reserve calculation formula based on known gas reservoir data and experience, but this method requires sufficient data support.

[0054] To address the challenges of data acquisition difficulties, the need for multiple iterations, and significant errors in existing technologies, this application proposes a method, apparatus, equipment, and medium for determining the dynamic control reserves of gas reservoirs under abnormally high pressure conditions, based on the material balance equation under abnormally high pressure conditions. By introducing a hyperbolic window, the decline index of the gas well during the hyperbolic window stage (the time period after the pressure wave propagates to the boundary, when the decline index n is between 0 and 1) is calculated. By using linear analysis on the cumulative gas production and natural gas output, a dynamic reserve model is constructed to determine the dynamic reserves of the gas reservoir.

[0055] The method for determining the dynamic control reserves of abnormal high-pressure gas reservoirs provided in this application aims to solve the above-mentioned technical problems in the prior art.

[0056] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0057] Figure 1 This is a schematic diagram illustrating a scenario for the dynamic control method for determining reserves in abnormally high-pressure gas reservoirs provided in an embodiment of this application. Figure 1 As shown, the main body executing this method can be a gas well dynamic control reserve determination system, which includes a calculation unit and an execution unit.

[0058] The computing unit can refer to the core unit that provides powerful computing power. In this application, the computing unit is used to calculate the viscosity of natural gas, isothermal compressibility coefficient, pseudo-pressure of the gas reservoir based on the gas reservoir parameters, as well as to calculate the decline index of the hyperbolic window stage.

[0059] The execution unit can refer to a unit used to handle the real-world problems faced by the system, that is, a module that applies learned knowledge to solve problems. In this application, the execution unit is used to receive instructions from the calculation unit, determine the natural gas production variable and cumulative gas production variable of the gas well under standard conditions, obtain the dynamic reserve model of the gas reservoir based on the relationship between the natural gas production variable and the cumulative gas production variable under standard conditions, produce a relationship diagram of the two variables, and determine the dynamic geological production of the abnormally high-pressure gas reservoir based on the relationship diagram of the two variables.

[0060] The execution entity of the dynamic control reserve determination method for abnormally high-pressure gas reservoirs provided in this application embodiment can also be a server. The server can be a computer, tablet, or other device. This embodiment does not impose any particular restrictions on the implementation method of the execution entity, as long as the execution entity can determine the parameters of the gas reservoir where the gas well is located, the quantification index of the reservoir's rock compressibility; determine the pseudo-pressure of the gas well based on the parameters of the gas reservoir; obtain the target coefficient based on the gas viscosity, isothermal compressibility coefficient, pseudo-pressure, and the quantification index of the reservoir's rock compressibility; determine the decline index of the gas well in the hyperbolic window stage based on the target coefficient and the pseudo-pressure of the gas well; determine the natural gas production variable and the cumulative gas production variable based on the decline index of the gas well in the hyperbolic window stage; and determine the dynamic geological reserves of the gas reservoir in the gas well based on the natural gas production variable and the cumulative gas production variable.

[0061] Among them, abnormally high-pressure gas reservoirs refer to gas reservoirs with a pressure coefficient greater than 1.8. Abnormally high-pressure gas reservoirs are usually characterized by abundant elastic energy and high pressure, and the production of single wells in these reservoirs is relatively high, laying a good foundation for high gas well production.

[0062] Figure 2 This is a flowchart illustrating the method for determining the dynamic control reserves of abnormally high-pressure gas reservoirs provided in this embodiment. The executing entity of this method can be a server or other servers; this embodiment does not impose any particular limitations. Figure 2 As shown, the method may include:

[0063] S201. Determine the parameters of the gas reservoir where the gas well is located, and the quantitative index of rock compressibility of the reservoir.

[0064] Among them, the parameters of the gas reservoir where the gas well is located include the basic parameters of the gas reservoir and the basic parameters of the reservoir.

[0065] Among these, basic gas reservoir parameters refer to parameters related to the state and properties of the physical gas, including pressure (P), temperature (T), and specific gravity (SG). These parameters are important indicators for describing the state and behavior of the gas, used to describe its properties, calculate its physical properties, and determine its behavior. In this application, basic gas reservoir parameters are used to calculate the viscosity of natural gas. Isothermal compressibility of natural gas and natural gas deviation factor Among them, basic reservoir parameters can refer to parameters characterizing reservoir properties, including rock compressibility coefficient. Rock compressibility quantification index Gas reservoir cross-sectional area parameters Reservoir thickness parameters Initial porosity parameters of the reservoir Fluid saturation.

[0066] Fluid saturation can refer to the ratio of fluid content in the reservoir to the reservoir pore volume. In this application, fluid saturation includes the initial gas saturation of the gas reservoir. Water saturation This application considers the case of pure gas, i.e. , .

[0067] Natural gas viscosity refers to the frictional force between gas molecules when the gas is in motion, and it can be calculated based on the specific gravity, temperature, and pressure of natural gas.

[0068] The isothermal compressibility coefficient of natural gas can be defined as the rate of change of natural gas volume with pressure under isothermal conditions.

[0069] The natural gas deviation factor can be defined as the ratio of the volume occupied by real gas to that of ideal gas under the same temperature and pressure.

[0070] Among them, the rock compressibility quantification index can refer to an indicator describing the degree to which rock compressibility affects reservoir fluid extraction. This is used when the rock is considered incompressible or the rock compressibility coefficient is... Quantitative index of rock compressibility in particularly small hours The value is 1, which satisfies the gas reservoir material balance equation under normal pressure (assuming the rock is incompressible).

[0071] S202. Determine the pseudo-pressure of the gas well based on the parameters of the gas reservoir where the gas well is located.

[0072] In this context, pseudo-pressure refers to the pressure calculated based on a given pressure pseudo-function. Since the density, viscosity, and deviation coefficient of natural gas are functions of pressure, its seepage state differs significantly from that of oil reservoirs. Therefore, in the process of solving the continuity equation, pseudo-pressure is introduced to linearize the equation set, allowing the study of gas reservoir seepage to utilize methods from oil reservoir seepage analysis. There is a one-to-one correspondence between the pressure pseudo-function and the pressure; that is, given the pressure, the pressure pseudo-function can be calculated, and vice versa.

[0073] This includes determining the basic gas reservoir parameters, and calculating the natural gas viscosity of the gas well based on these parameters. Isothermal compressibility of natural gas and natural gas deviation factor Based on the pseudo-pressure formula, the pseudo-pressure corresponding to each pressure is calculated. The pseudo-pressure formula is:

[0074]

[0075] in, For formation pressure, For natural gas deviation factor, T is the reservoir temperature. The relative molecular mass of the gas. It is a constant value. For the density of natural gas, For natural gas viscosity, It is the isothermal compressibility coefficient of natural gas.

[0076] Among them, the average formation pressure is The units are MPa and bottom hole flowing pressure. The unit is MPa. The mean formation pressure and bottom hole flowing pressure are calculated, and then substituted into the definition formula for pseudo-pressure, the pseudo-pressure of the mean formation pressure can be calculated. pseudo-pressure and bottom hole flowing pressure .

[0077] The method provided in this application can be used for bottom hole flowing pressure. The situation remains unchanged.

[0078] In this embodiment of the application, determining the pseudo-pressure of the gas well based on the parameters of the gas reservoir in which the gas well is located includes:

[0079] Based on the parameters of the gas reservoir where the gas well is located, determine the natural gas viscosity, natural gas isothermal compressibility coefficient, and natural gas deviation factor of the gas well;

[0080] The simulated pressure of the gas well is determined based on the parameters of the gas reservoir, the viscosity of the natural gas, and the natural gas deviation factor.

[0081] S203. Based on the gas viscosity, isothermal compressibility coefficient, pseudo-pressure, and reservoir rock compressibility quantification index of the gas well, the target coefficient is obtained.

[0082] In this embodiment of the application, the target coefficient can specify the gas well decline index during bottom hole pressure production. The coefficient of the target coefficient is given by the formula:

[0083]

[0084] Among them, the gas well decline index can refer to an important parameter for judging the decline type and determining the decline law. In this application, the gas well decline index during production at a constant bottom hole pressure is used. The expression is:

[0085]

[0086] Among them, the gas well decline index during production at constant bottom hole pressure The expression is derived from the formula. The expressions for the gas well productivity index, natural gas production under standard conditions, material balance under abnormal high pressure, and gas well decline rate are determined. Substituting these expressions into the gas well decline rate expression yields an expression that includes the gas well decline rate under initial conditions. Substituting this expression into the gas well decline index expression and simplifying it, we obtain the gas well decline index for production at constant bottomhole pressure. The expression.

[0087] Among them, the gas well productivity index refers to a parameter that evaluates the productivity of a gas well. For the case where the gas reservoir boundary is circular, the expression for the gas well productivity index is:

[0088]

[0089] in, For reservoir rock permeability, For reservoir thickness, This refers to the density of a gas under standard conditions, expressed in g / cm³. 3 ,

[0090]

[0091] in, Indicates the seepage radius of the gas reservoir and Indicates the radius of the gas wellbore.

[0092] The boundary control flow stage refers to the stage after the pressure change propagates to each boundary during extraction. Before the pressure propagates to the boundary, the formation can be considered to be infinitely large. Therefore, this application studies the boundary control flow stage (at which point the gas well can reflect the state of the entire formation).

[0093] The expression for natural gas production when the gas well enters the boundary control flow, i.e., the expression for natural gas production under standard conditions, is as follows:

[0094]

[0095] in, This represents the natural gas production under standard conditions. This is the pseudo-pressure of the formation mean pressure. The pseudo-pressure is the bottom hole flowing pressure. This is the gas well production capacity index.

[0096] Among them, the material balance equation can refer to the equation used to describe the material balance state of an oil or gas reservoir at a certain moment. The material balance equation under abnormal high pressure conditions is:

[0097]

[0098] in, The density of the gas under initial conditions, in units. , The average density of the reservoir gas is expressed in units of... , The density of a gas under standard conditions, in units of , Natural gas production under standard conditions, per unit , It is a quantitative index of rock compressibility. Original geological reserves, Where h is the cross-sectional area of ​​the gas reservoir, and h is the reservoir thickness. The initial porosity of the reservoir. This represents the initial gas saturation of the gas reservoir.

[0099] The rock compressibility quantification index is related to the rock compressibility coefficient, reservoir porosity, initial gas saturation, and water saturation of the gas reservoir, and satisfies the following formula:

[0100]

[0101] in, is the isothermal compressibility coefficient of the gas. The comprehensive compressibility coefficient of the reservoir. The average porosity of the reservoir. This represents the gas saturation level of the gas reservoir. The rock compressibility coefficient, This represents the initial water saturation of the gas reservoir. This represents the original formation pressure.

[0102] The gas well decline rate refers to the rate of change in gas well production per unit time, reflecting the speed of decline in oil and gas well production, i.e., the percentage decrease in production per unit time. The formula for the gas well decline rate is:

[0103]

[0104] Natural gas production under standard conditions The gas well productivity index expression and the material balance equation under abnormal high pressure conditions are used as inputs into the decline rate formula to determine the gas well decline rate under abnormal high pressure conditions with constant bottom hole pressure:

[0105]

[0106] in, The average viscosity of natural gas in the reservoir. The average isothermal compressibility coefficient of the natural gas in the reservoir. The quantitative index of rock compressibility under initial conditions. The decline rate at the initial moment of the gas well is expressed as:

[0107]

[0108] in, Let be the viscosity of natural gas under initial conditions. is the isothermal compressibility coefficient of natural gas under initial conditions.

[0109] The formula for calculating the gas well decline index is as follows:

[0110]

[0111] Will By substituting the formula for calculating the gas well decline index, the gas well decline index for production at a constant bottom hole pressure under abnormally high pressure conditions is determined. The expression:

[0112]

[0113] Right now ,in, The target coefficient of this expression is... This is the pseudo-pressure variation coefficient in the expression, where the decreasing exponent is... It can be obtained from the basic parameters of the gas reservoir.

[0114] In this application, the variation law of the gas well decline index is taken into account, and Transforming it into the above form facilitates subsequent integral processing and helps determine the decreasing exponent in the hyperbolic window stage. .

[0115] In this embodiment of the application, the target coefficient is obtained based on the gas viscosity, isothermal compressibility coefficient, pseudo-pressure, and reservoir rock compressibility quantification index of the gas well, including:

[0116] The first ratio coefficient is determined based on the gas viscosity of the gas well, the isothermal compressibility coefficient of the gas well, and the quantitative index of rock compressibility of the reservoir.

[0117] Based on the first ratio coefficient and the pseudo-pressure of the gas well, determine the target coordinate point in the double logarithmic coordinate system;

[0118] Determine the target coefficients based on the target coordinates in the logarithmic coordinate system.

[0119] The system generates a first ratio coefficient based on the gas viscosity of the gas well, the isothermal compressibility coefficient of the gas well, and the quantitative index of rock compressibility of the reservoir. The pseudo pressure of the gas well Using the first ratio coefficient as the ordinate, determine the target coordinate point in a log-log coordinate system, generate the slope value of the target coordinate point, and take the negative of this slope value as the target coefficient. .

[0120] S204. Based on the target coefficient and the pseudo-pressure of the gas well, determine the decline index of the gas well in the hyperbolic window stage.

[0121] The hyperbolic window stage refers to the period during which the gas well decline exponent n is between 0 and 1, approximately constant, also known as the early stage of boundary control flow. Hyperbolic window stage decline exponent It can be obtained through integration.

[0122] Among these, a strict hyperbolic decline requires a constant decline exponent, which is only possible under ideal gas conditions. However, during oilfield extraction, formation pressure changes. When the pressure wave propagates from the extraction point to the boundary of the boundary control flow, it enters the boundary control flow stage. For a period of time afterward, the following occurs:

[0123]

[0124] At this point, the decline exponent is approximately constant, so it is assumed that the requirements for hyperbolic decline are met. The decline exponent during production at constant bottom hole pressure can be integrated to obtain the decline exponent of the gas well in the hyperbolic window stage. .

[0125] The decline index of a gas well under abnormally high pressure conditions and constant bottom hole pressure production is obtained by integral processing as follows: The decline index of the gas well during the hyperbolic window stage is then obtained. :

[0126]

[0127] S205. Based on the decline index of the gas well during the hyperbolic window stage, determine the natural gas production variable and the cumulative gas production variable.

[0128] The cumulative gas production is determined based on the decline index of the gas well during the hyperbolic window stage, the initial decline rate of the gas well, and the natural gas production under standard conditions.

[0129] The formula for the cumulative gas production of a gas well is as follows:

[0130]

[0131] in, This represents the cumulative gas production of the gas well. This represents the initial natural gas production.

[0132] Among them, based on the decreasing index of gas wells in the hyperbolic window stage Determine the natural gas production variables of the gas well under standard conditions. Based on the decreasing index of gas wells in the hyperbolic window stage And the cumulative gas production, determine the expression for the cumulative gas production variable, which is as follows:

[0133]

[0134] In this embodiment of the application, the natural gas production variable and the cumulative gas production variable are determined based on the decline index of the gas well during the hyperbolic window stage, including:

[0135] Determine the natural gas production and cumulative gas production of the gas well under standard conditions;

[0136] The natural gas production variable is determined based on the natural gas production of the gas well under standard conditions and the decline index of the gas well during the hyperbolic window phase.

[0137] The cumulative gas production variable is determined based on the cumulative gas production of the gas well, the decline index during the hyperbolic window stage, the viscosity of natural gas, the isothermal compressibility coefficient of natural gas, and the pseudo-pressure.

[0138] S206. Determine the dynamic geological reserves of the gas well based on the natural gas production variables and cumulative gas production variables.

[0139] Among them, the dynamic geological reserves of a gas reservoir can refer to the proven recoverable reserves accumulated by the gas reservoir under certain specific conditions after a period of production.

[0140] Among them, a dynamic gas reservoir reserve model is generated based on natural gas production variables and cumulative gas production variables.

[0141]

[0142] Based on the input basic parameters of the gas reservoir and natural gas production data, a dynamic reserve model of the producing gas reservoir is generated, and the dynamic geological reserves of the gas reservoir in the gas well are determined based on the curve. .

[0143] The dynamic reserve model of the gas reservoir is obtained by transforming the formula for the cumulative gas production of gas wells: [The formula for the cumulative gas production of gas wells is then transformed.]

[0144]

[0145] Rewritten as:

[0146]

[0147] The well decline rate under initial conditions. Expression, natural gas production under standard conditions Expression, Gas Well Productivity Index Substituting the expression into the above equation, we obtain the dynamic gas reservoir reserve model:

[0148]

[0149] In this embodiment of the application, determining the dynamic geological reserves of the gas reservoir in the gas well based on natural gas production variables and cumulative gas production variables includes:

[0150] A dynamic gas reservoir reserve model is generated based on natural gas production variables and cumulative gas production variables.

[0151] Based on the dynamic reserve model of the gas reservoir, the dynamic geological reserves of the gas reservoir in the gas well are determined.

[0152] This involves using data on natural gas production under standard conditions, cumulative gas production during the hyperbolic window stage, and basic reservoir parameters to determine the production... In the relationship diagram, selecting the straight line segment ("hyperbolic window"), the extrapolation and the intercept on the horizontal axis represent the dynamic geological reserves of the gas well. .

[0153] Among them, the natural gas production of gas wells under standard conditions The numerical value, cumulative gas production during the hyperbolic window stage The data are measurable known quantities.

[0154] In this embodiment of the application, the dynamic gas reservoir reserve model is generated based on the natural gas production variable and the cumulative gas production variable. The dynamic gas reservoir reserve model is as follows:

[0155]

[0156] For natural gas production variables in the model, For the cumulative gas production variable in the dynamic gas reservoir reserve model,

[0157] in, This represents the natural gas production of a gas well under standard conditions. G represents the initial natural gas production, and G represents the dynamic geological reserves of the gas reservoir. It is a constant value. The gas density under initial conditions, The viscosity of natural gas under initial conditions. The isothermal compressibility coefficient of natural gas under initial conditions. This is the pseudo-pressure corresponding to the original formation pressure. The pseudo-pressure is the bottom hole flowing pressure. The quantitative index of rock compressibility under initial conditions. This represents the decreasing index of a gas well during the hyperbolic window phase. This represents the cumulative gas production of the gas well.

[0158] In this embodiment of the application, determining the dynamic geological reserves of the gas reservoir in the gas well based on the dynamic reserve model includes:

[0159] Determine the target natural gas production variable, where the target natural gas production variable represents a natural gas production variable of 0;

[0160] Based on the target natural gas production variables and the dynamic reserve model of the gas reservoir, the dynamic geological reserves of the gas well are determined.

[0161] Among them, using the linear analysis method, the dynamic reserve model of gas reservoirs can be regarded as an equation

[0162]

[0163] in, ,when hour, The dynamic geological reserves G of the gas reservoir in the gas well is at this time. value.

[0164] The method for determining the dynamic control reserves of abnormally high-pressure gas reservoirs provided in this application determines the natural gas production variable and the cumulative gas production variable by calculating the decline index of the hyperbolic window stage, establishes the relationship between natural gas production and cumulative gas production under standard conditions, generates a dynamic reserve model of the gas reservoir, and plots the model to determine the dynamic reserves of the gas reservoir. It does not require iteration, which reduces the difficulty of operation, and does not require manual fitting, which reduces the calculation error.

[0165] Figure 3 This is a flowchart illustrating another method for determining the dynamic control reserves of abnormally high-pressure gas reservoirs provided in an embodiment of this application. Figure 3 As shown, the method includes:

[0166] S301. Based on the basic parameters of the gas reservoir, determine the viscosity of natural gas, the gas deviation factor of natural gas, the isothermal compressibility coefficient of natural gas, and the pseudo-pressure of the gas well.

[0167] S302. Determine the curve of rock compressibility quantification index as a function of formation pressure.

[0168] S303. Calculate the decline index of the hyperbolic window stage based on the viscosity of natural gas, the gas deviation factor of natural gas, the isothermal compressibility coefficient of natural gas, and the pseudo-pressure of the gas well.

[0169] Among them, when the original formation pressure of the gas reservoir is 33.09 MPa and the original geological reserves are... The reservoir temperature is 93.33℃, the natural gas specific gravity is 0.65, and the gas well is producing at a constant bottom hole pressure of 3.45 MPa. The rock compressibility coefficient is selected.

[0170] At that time, the calculation result of the decreasing exponent in the hyperbolic window stage is:

[0171]

[0172] S304. Determine the dynamic geological reserves of abnormally high-pressure gas reservoirs using the linear analysis method.

[0173] Determine the decreasing exponent Then, calculations were performed based on the production data. Using this as the ordinate; then calculate the values ​​at different times according to the formula. Using the x-axis as the horizontal axis, a graph showing the relationship between the two is plotted. It can be seen that the two are approximately linearly related, and the intersection of the straight lines on the horizontal axis represents the dynamic geological reserves of the abnormally high-pressure gas reservoir. .

[0174] Figure 4 This is a graph showing the variable relationships in the dynamic gas reservoir model provided in this application embodiment. The graph represents... Figure 3 Step S306 involves determining the dynamic geological reserves of an abnormally high-pressure gas reservoir based on the dynamic geological model of the gas reservoir. In this figure, the vertical axis represents the natural gas production variable in the model. The horizontal axis represents the cumulative gas production variable in the dynamic gas reservoir model. The x-coordinate of the intersection of the x-axis and y-axis represents the dynamic geological reserves G of the abnormally high-pressure gas reservoir.

[0175] Figure 5 A schematic diagram of the structure of the dynamic control and reserve determination device for abnormal high-pressure gas reservoirs provided in this application embodiment is shown below. Figure 5 As shown, the device 50 for determining the dynamic control reserves of a gas well includes: a determination module 501, a first calculation module 502, a second calculation module 503, a third calculation module 504, a fourth calculation module 505, and an execution module 506. Wherein:

[0176] The determination module 501 is used to determine the parameters of the gas reservoir where the gas well is located and the quantitative index of rock compressibility of the reservoir.

[0177] The first calculation module 502 is used to determine the pseudo pressure of the gas well based on the parameters of the gas reservoir where the gas well is located.

[0178] The second calculation module 503 is used to obtain the target coefficient based on the gas viscosity, isothermal compressibility coefficient, pseudo-pressure, and reservoir rock compressibility quantification index of the gas well.

[0179] The third calculation module 504 is used to determine the decline index of the gas well in the hyperbolic window stage based on the target coefficient and the pseudo pressure of the gas well.

[0180] The fourth calculation module 505 is used to determine the natural gas production variable and the cumulative gas production variable based on the decline index of the gas well in the hyperbolic window stage;

[0181] Execution module 506 is used to determine the dynamic geological reserves of a gas well based on natural gas production variables and cumulative gas production variables.

[0182] In this embodiment of the application, the first calculation module 502 may also be specifically used for:

[0183] Based on the parameters of the gas reservoir where the gas well is located, determine the natural gas viscosity, natural gas isothermal compressibility coefficient, and natural gas deviation factor of the gas well;

[0184] The simulated pressure of the gas well is determined based on the parameters of the gas reservoir, the viscosity of the natural gas, and the natural gas deviation factor.

[0185] In this embodiment of the application, the second calculation module 503 may also be specifically used for:

[0186] The first ratio coefficient is obtained based on the gas viscosity of the gas well, the isothermal compressibility coefficient of the gas well, and the quantitative index of rock compressibility of the reservoir.

[0187] Based on the first ratio coefficient and the pseudo-pressure of the gas well, determine the target coordinate point in the double logarithmic coordinate system;

[0188] Determine the target coefficients based on the target coordinates in the logarithmic coordinate system.

[0189] In this embodiment of the application, the fourth calculation module 505 may also be specifically used for:

[0190] Determine the natural gas production and cumulative gas production of the gas well under standard conditions;

[0191] The natural gas production variable is determined based on the natural gas production of the gas well under standard conditions and the decline index of the gas well during the hyperbolic window phase.

[0192] The cumulative gas production variable is determined based on the cumulative gas production of the gas well, the decline index during the hyperbolic window stage, the viscosity of natural gas, the isothermal compressibility coefficient of natural gas, and the pseudo-pressure.

[0193] In this embodiment of the application, the execution module 506 may also be specifically used for:

[0194] A dynamic gas reservoir reserve model is generated based on natural gas production variables and cumulative gas production variables.

[0195] Based on the dynamic reserve model of the gas reservoir, the dynamic geological reserves of the gas reservoir in the gas well are determined.

[0196] In this embodiment of the application, the execution module 506 may also be specifically used for:

[0197]

[0198] For the natural gas production variable in the dynamic reserves model of the gas reservoir, For the cumulative gas production variable in the dynamic gas reservoir reserve model,

[0199] in, This represents the natural gas production of a gas well under standard conditions. G represents the initial natural gas production, and G represents the dynamic geological reserves of the gas reservoir. It is a constant value. The gas density under initial conditions, The viscosity of natural gas under initial conditions. The isothermal compressibility coefficient of natural gas under initial conditions. This is the pseudo-pressure corresponding to the original formation pressure. The pseudo-pressure is the bottom hole flowing pressure. The quantitative index of rock compressibility under initial conditions. This represents the decreasing index of a gas well during the hyperbolic window phase. This represents the cumulative gas production of the gas well.

[0200] In this embodiment of the application, the execution module 506 may also be specifically used for:

[0201] Determine the target natural gas production variable, where the target natural gas production variable represents a natural gas production variable of 0;

[0202] Based on the target natural gas production variables and the dynamic reserve model of the gas reservoir, the dynamic geological reserves of the gas well are determined.

[0203] Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 6 As shown, the electronic device 60 includes:

[0204] The electronic device 60 may include a processor 601 with one or more processing cores, a memory 602 with one or more computer-readable storage media, a communication component 603, and other components. The processor 601, memory 602, and communication component 603 are connected via a bus 604.

[0205] In the specific implementation process, at least one processor 601 executes computer execution instructions stored in memory 602, causing at least one processor 601 to execute the above-mentioned method for determining the dynamic control reserves of gas wells.

[0206] The specific implementation process of processor 601 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0207] In the above Figure 6 In the illustrated embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0208] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0209] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0210] In some embodiments, a computer program product is also provided, including a computer program or instructions that, when executed by a processor, implement the steps in the above-described method for determining the dynamic control reserves of any abnormal high-pressure gas reservoir.

[0211] For details on the implementation of each of the above operations, please refer to the previous examples, which will not be repeated here.

[0212] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be performed by instructions, or by instructions controlling related hardware. These instructions can be stored in a computer-readable storage medium and loaded and executed by a processor.

[0213] Therefore, embodiments of this application provide a computer-readable storage medium storing a plurality of instructions that can be loaded by a processor to execute the steps in any of the dynamic control methods for determining reserves in abnormal high-pressure gas reservoirs provided in embodiments of this application.

[0214] The storage medium may include: read-only memory (ROM), random access memory (RAM), disk or optical disk, etc.

[0215] According to one aspect of this application, a computer program product or computer program is provided, the computer program product or computer program including computer instructions stored in a computer-readable storage medium.

[0216] Since the instructions stored in the storage medium can execute the steps in any of the dynamic control methods for determining reserves of abnormal high-pressure gas reservoirs provided in the embodiments of this application, the beneficial effects that any of the dynamic control methods for determining reserves of abnormal high-pressure gas reservoirs provided in the embodiments of this application can achieve can be realized. For details, please refer to the previous embodiments, which will not be repeated here.

[0217] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0218] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A method for determining the reserves of an abnormally high-pressure gas reservoir through dynamic control, characterized in that, A system for determining reserves in dynamic control of gas wells, including: Determine the parameters of the gas reservoir where the gas well is located, and the quantitative index of rock compressibility of the reservoir; the quantitative index of rock compressibility satisfies the following formula: ； in, It is a quantitative index of rock compressibility. This represents the initial gas saturation of the gas reservoir. is the isothermal compressibility coefficient of the gas. This represents the gas saturation level of the gas reservoir. The rock compressibility coefficient, This represents the initial water saturation of the gas reservoir. The original formation pressure, The average formation pressure is the reservoir average pressure; the simulated pressure of the gas well is determined based on the parameters of the gas reservoir in which the gas well is located. The target coefficient is obtained based on the natural gas viscosity, isothermal compressibility coefficient, pseudo-pressure, and the reservoir rock compressibility quantification index of the gas well; the target coefficient is expressed as: in, The average viscosity of natural gas in the reservoir. The average isothermal compressibility coefficient of the natural gas in the reservoir. Mean formation pressure of the reservoir The corresponding pseudo-pressure; based on the target coefficient and the pseudo-pressure of the gas well, the decline index of the gas well in the hyperbolic window stage is determined; the decline index of the gas well in the hyperbolic window stage satisfies the following formula: ； in, This represents the decreasing index of a gas well during the hyperbolic window phase. Original formation pressure The corresponding pseudo-pressure, Bottom hole flowing pressure The corresponding pseudo-pressure; Based on the decreasing index of the gas well during the hyperbolic window stage, determine the natural gas production variable and the cumulative gas production variable; Based on the natural gas production variables and the cumulative gas production variables, a dynamic gas reservoir reserve model is generated; Based on the gas reservoir dynamic reserve model, determine the dynamic geological reserves of the gas well; The dynamic reserve model of the gas reservoir is as follows: ， The natural gas production variable in the dynamic reserves model of the gas reservoir is... The cumulative gas production variable in the dynamic gas reservoir reserve model is... in, This represents the natural gas production of a gas well under standard conditions. G represents the initial natural gas production, and G represents the dynamic geological reserves of the gas reservoir. It is a constant value. The gas density under initial conditions, The viscosity of natural gas under initial conditions. The isothermal compressibility coefficient of natural gas under initial conditions. This is the pseudo-pressure corresponding to the original formation pressure. The pseudo-pressure of the bottom hole flowing pressure. The quantitative index of rock compressibility under initial conditions. This represents the decreasing index of a gas well during the hyperbolic window phase. This represents the cumulative gas production of the gas well.

2. The method according to claim 1, characterized in that, The step of determining the pseudo-pressure of the gas well based on the parameters of the gas reservoir in which the gas well is located includes: Based on the parameters of the gas reservoir where the gas well is located, determine the natural gas viscosity, natural gas isothermal compressibility coefficient, and natural gas deviation factor of the gas well; The simulated pressure of the gas well is determined based on the parameters of the gas reservoir, the viscosity of the natural gas, and the natural gas deviation factor.

3. The method according to claim 1, characterized in that, The target coefficients, obtained based on the gas viscosity, isothermal compressibility coefficient, pseudo-pressure, and the reservoir rock compressibility quantification index of the gas well, include: A first ratio coefficient is determined based on the natural gas viscosity, isothermal compressibility coefficient, and rock compressibility quantification index of the gas well; the first ratio coefficient is expressed as: ； Based on the first ratio coefficient and the pseudo-pressure of the gas well, determine the target coordinate point in the double logarithmic coordinate system; The target coefficients are determined based on the target coordinate points in the double logarithmic coordinate system.

4. The method according to claim 1, characterized in that, The determination of natural gas production variables and cumulative gas production variables based on the decline index of the gas well during the hyperbolic window stage includes: Determine the natural gas production and cumulative gas production of the gas well under standard conditions; The natural gas production variable is determined based on the natural gas production of the gas well under standard conditions and the decreasing index of the gas well during the hyperbolic window phase. The cumulative gas production variable is determined based on the cumulative gas production of the gas well, the decline index during the hyperbolic window stage, the viscosity of natural gas, the isothermal compressibility coefficient of natural gas, and the pseudo-pressure.

5. The method according to claim 1, characterized in that, The step of determining the dynamic geological reserves of the gas well based on the gas reservoir dynamic reserve model includes: Determine a target natural gas production variable, wherein the target natural gas production variable represents the natural gas production variable as 0; The dynamic geological reserves of the gas well are determined based on the target natural gas production variable and the dynamic reserve model of the gas reservoir.

6. A device for dynamically controlling and determining reserves in an abnormally high-pressure gas reservoir, characterized in that, Systems applied to the determination of dynamic gas reservoir reserves include: The determination module is used to determine the parameters of the gas reservoir where the gas well is located and the quantitative index of rock compressibility of the reservoir; the quantitative index of rock compressibility satisfies the following formula: ； in, It is a quantitative index of rock compressibility. This represents the initial gas saturation of the gas reservoir. is the isothermal compressibility coefficient of the gas. This represents the gas saturation level of the gas reservoir. The rock compressibility coefficient, This represents the initial water saturation of the gas reservoir. The original formation pressure, The mean formation pressure of the reservoir; The first calculation module is used to determine the pseudo pressure of the gas well based on the parameters of the gas reservoir where the gas well is located; The second calculation module is used to obtain a target coefficient based on the natural gas viscosity, isothermal compressibility coefficient, pseudo-pressure, and the reservoir rock compressibility quantification index of the gas well; the target coefficient is expressed as: in, The average viscosity of natural gas in the reservoir. The average isothermal compressibility coefficient of the natural gas in the reservoir. Mean formation pressure of the reservoir The corresponding pseudo-pressure; The third calculation module is used to determine the decline index of the gas well in the hyperbolic window stage based on the target coefficient and the pseudo-pressure of the gas well; the decline index of the gas well in the hyperbolic window stage satisfies the following formula: ； in, This represents the decreasing index of a gas well during the hyperbolic window phase. Original formation pressure The corresponding pseudo-pressure, Bottom hole flowing pressure The corresponding pseudo-pressure; The fourth calculation module is used to determine the natural gas production variable and the cumulative gas production variable based on the decreasing index of the gas well in the hyperbolic window stage; The execution module is used to generate a dynamic gas reservoir reserve model based on the natural gas production variable and the cumulative gas production variable. Based on the gas reservoir dynamic reserve model, determine the dynamic geological reserves of the gas well; The dynamic reserve model of the gas reservoir is as follows: ， The natural gas production variable in the dynamic reserves model of the gas reservoir is... The cumulative gas production variable in the dynamic gas reservoir reserve model is... in, This represents the natural gas production of a gas well under standard conditions. G represents the initial natural gas production, and G represents the dynamic geological reserves of the gas reservoir. It is a constant value. The gas density under initial conditions, The viscosity of natural gas under initial conditions. The isothermal compressibility coefficient of natural gas under initial conditions. This is the pseudo-pressure corresponding to the original formation pressure. The pseudo-pressure of the bottom hole flowing pressure. The quantitative index of rock compressibility under initial conditions. This represents the decreasing index of a gas well during the hyperbolic window phase. This represents the cumulative gas production of the gas well.

7. An electronic device, characterized in that, include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the method as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1 to 5.

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