Dynamic geological reserve determination method, device, equipment and medium

Abstract

The application provides a dynamic geological reserve determination method, device, equipment and medium, and the method comprises the following steps: determining the natural gas viscosity, natural gas isothermal compressibility coefficient and natural gas deviation factor of natural gas in a gas well; determining a target coefficient and a pseudo pressure of the natural gas in the gas well under each pressure according to the natural gas viscosity, natural gas isothermal compressibility coefficient and natural gas deviation factor of the natural gas in the gas well; determining a decline index of the gas well during gas well production according to the target coefficient and the pseudo pressure of the natural gas in the gas well under each pressure; determining a hyperbolic window decline index of the gas well under a variable bottom-hole flowing pressure and a target cumulative gas production of the gas well at different time according to the decline index of the gas well during gas well production; and determining a dynamic geological reserve of the gas well according to the hyperbolic window decline index of the gas well under the variable bottom-hole flowing pressure and the target cumulative gas production of the gas well at different time. The method provided by the application improves the accuracy of determining the dynamic geological reserve of the gas well.

Description

Technical Field

[0001] This application relates to the field of computer technology, and in particular to a method, apparatus, equipment and medium for determining dynamic geological reserves. Background Technology

[0002] Dynamic reserves of a gas reservoir refer to the capacity of natural gas that can flow out of the reservoir when all wells are in production until the natural gas production and formation pressure within the affected area reach zero, under the condition that existing technology and well network production methods remain unchanged. Currently, the main methods for calculating dynamic reserves of gas reservoirs are the mass balance method and the production decline analysis method.

[0003] The material balance method only requires two or more shut-in pressure tests to calculate dynamic reserves. However, since obtaining formation pressure is difficult, iterative methods are usually used to solve the problem. The production decline analysis method uses the Arps decline equation to solve the problem. It is suitable for constant bottom hole flowing pressure by default. However, in oilfield production, when the oilfield production conditions remain unchanged, the flowing pressure changes with the formation pressure. Therefore, it is necessary to manually fit the modern production decline analysis chart.

[0004] However, current methods for determining the dynamic reserves of gas reservoirs have the problem of poor reserve determination results. Summary of the Invention

[0005] This application provides a method, apparatus, equipment, and medium for determining dynamic geological reserves, in order to solve the problem that existing methods for determining dynamic reserves of gas reservoirs have poor reserve determination results.

[0006] In a first aspect, this application provides a dynamic geological reserve determination method, applied to a dynamic geological reserve determination system, the method comprising:

[0007] Determine the viscosity of natural gas in the gas well at various pressures, the isothermal compressibility coefficient of natural gas in the gas well at various pressures, and the deviation factor of natural gas in the gas well at various pressures.

[0008] Based on the viscosity of natural gas in the gas well at various pressures, the isothermal compressibility coefficient of natural gas in the gas well at various pressures, and the deviation factor of natural gas in the gas well at various pressures, the target coefficient and the pseudo pressure of natural gas in the gas well at various pressures are determined.

[0009] The decline index of the gas well during gas production is determined based on the target coefficient and the pseudo-pressure of natural gas in the gas well under various pressures.

[0010] Based on the decline index of the gas well during gas well production, determine the hyperbolic window decline index of the gas well under varying bottom hole flowing pressure and the target cumulative gas production of the gas well at different times;

[0011] The dynamic geological reserves of a gas well are determined based on the hyperbolic window decline index under varying bottomhole flowing pressure and the target cumulative gas production at different times.

[0012] In this embodiment of the application, the target coefficient and the pseudo-pressure of natural gas at various pressures are determined based on the viscosity of natural gas at various pressures, the isothermal compressibility coefficient of natural gas at various pressures, and the deviation factor of natural gas at various pressures. This includes:

[0013] The initial target coefficients are obtained based on the viscosity of natural gas in the gas well at various pressures and the isothermal compressibility coefficient of natural gas in the gas well at various pressures.

[0014] Based on the initial target coefficient and target parameter, the target coefficient is determined. The target parameter characterizes the influence coefficient of rock compressibility in the gas well on the stored fluid. When the rock is considered incompressible or the rock compressibility is particularly small, the target parameter value is 1.

[0015] Based on the natural gas viscosity and deviation factor of natural gas in the gas well at various pressures, the pseudo-pressure of natural gas in the gas well at various pressures is determined.

[0016] In this embodiment of the application, the target parameter satisfies:

[0017] ,

[0018] This represents the original gas saturation level of the gas reservoir. The isothermal compressibility coefficient of natural gas. The rock compressibility coefficient, This represents the original bound water saturation of the strata. The original formation pressure, This refers to formation pressure.

[0019] In this embodiment of the application, the decline index of the gas well during gas well production is determined based on the target coefficient and the pseudo-pressure of natural gas in the gas well at various pressures, including:

[0020] Determine the ordinate of the double logarithmic curve based on the target coefficient;

[0021] The horizontal axis of the double logarithmic curve is determined based on the pseudo-pressure of natural gas in the gas well under various pressures.

[0022] Based on the ordinate and abscissa of the double logarithmic curve, the decline index of the gas well during gas well production is determined. The decline index of the gas well during gas well production represents the opposite of the slope of the double logarithmic curve.

[0023] In this embodiment of the application, the decline index of the gas well during gas well production satisfies:

[0024] ,

[0025] For the target parameters, For the viscosity of natural gas, The isothermal compressibility coefficient of natural gas. This represents the pseudo-pressure of natural gas in the gas well under various pressure conditions. This refers to formation pressure.

[0026] In this embodiment of the application, the hyperbolic window decline index of the gas well under varying bottomhole flowing pressure and the target cumulative gas production of the gas well at different times are determined based on the decline index of the gas well during gas well production, including:

[0027] Based on the pseudo-pressure of natural gas in the gas well under various pressures, the decline index of the gas well during production is integrated to obtain the hyperbolic window decline index of the gas well under varying bottom hole pressure. The hyperbolic window decline index of the gas well under varying bottom hole pressure satisfies the following:

[0028] ,

[0029] This represents the original formation pressure of the natural gas. The pseudo-pressure is the pressure under the original formation pressure of natural gas. The final measured bottom hole flowing pressure, For the target parameters, For the viscosity of natural gas, The isothermal compressibility coefficient of natural gas. This represents the pseudo-pressure of natural gas in the gas well under various pressure conditions. Formation pressure;

[0030] Based on the hyperbolic window decline index of the gas well under varying bottomhole flowing pressure, the target cumulative gas production of the gas well at different times is determined, and the target cumulative gas production of the gas well at different times satisfies:

[0031] ,

[0032] The density of natural gas under the original formation pressure. The viscosity of natural gas under the original formation pressure. The isothermal compressibility coefficient of natural gas under the original formation pressure. This represents the original formation pressure of the natural gas. The pseudo-pressure is the pressure under the original formation pressure of natural gas. For a constant value, The target parameters are those under the original formation pressure. This represents the cumulative natural gas production under standard conditions.

[0033] In this embodiment of the application, the dynamic geological reserves of the gas well are determined based on the hyperbolic window decline index under varying bottomhole flowing pressure and the target cumulative gas production of the gas well at different times, including:

[0034] Based on the hyperbolic window decline index of a gas well under varying bottom hole pressure, the corresponding value of the standard gas production under the hyperbolic window decline index is obtained.

[0035] Based on the corresponding value of the standard natural gas production under the hyperbolic window decline index and the target cumulative gas production of the gas well at different times, a dynamic geological reserve relationship model is generated.

[0036] Based on the dynamic geological reserve relationship model, the dynamic geological reserves of the gas well are determined.

[0037] Secondly, this application provides a dynamic geological reserve determination device, the device comprising:

[0038] The first determining module is used to determine the viscosity of natural gas in the gas well at various pressures, the isothermal compressibility coefficient of natural gas in the gas well at various pressures, and the deviation factor of natural gas in the gas well at various pressures.

[0039] The second determining module is used to determine the target coefficient and the pseudo pressure of natural gas in the gas well at various pressures based on the viscosity of natural gas in the gas well at various pressures, the isothermal compressibility coefficient of natural gas in the gas well at various pressures, and the deviation factor of natural gas in the gas well at various pressures.

[0040] The third determination module is used to determine the decline index of the gas well during gas well production based on the target coefficient and the pseudo pressure of natural gas in the gas well at various pressures.

[0041] The fourth determination module is used to determine the hyperbolic window decline index of the gas well under varying bottom hole pressure and the target cumulative gas production of the gas well at different times, based on the decline index of the gas well during gas well production.

[0042] The dynamic geological reserves determination module is used to determine the dynamic geological reserves of a gas well based on the hyperbolic window decline index under varying bottom hole flowing pressure and the target cumulative gas production of the gas well at different times.

[0043] Thirdly, this application provides an electronic device, including: a processor, and a memory communicatively connected to the processor;

[0044] The memory stores instructions that the computer executes;

[0045] The processor executes computer execution instructions stored in memory to implement the methods of the embodiments of this application.

[0046] 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.

[0047] The dynamic geological reserves determination method, apparatus, equipment, and medium provided in this application determine the viscosity, isothermal compressibility, and deviation factor of natural gas in a gas well at various pressures. Based on these parameters, target coefficients and pseudo-pressures are determined. This method determines the decline index of a gas well during production; based on the decline index during production, it determines the hyperbolic window decline index of the gas well under varying bottomhole flowing pressure and the target cumulative gas production at different times; and based on the hyperbolic window decline index of the gas well under varying bottomhole flowing pressure and the target cumulative gas production at different times, it determines the dynamic geological reserves of the gas well. This method enables the determination of the dynamic geological production of abnormally high-pressure gas reservoirs while considering changes in bottomhole flowing pressure, avoiding the need for multiple iterations in existing technologies. The data involved is not complex, and the acquisition method is simple, reducing the operational difficulty and improving the accuracy of reserve determination. Attached Figure Description

[0048] 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.

[0049] Figure 1 A flowchart illustrating a method for determining dynamic geological reserves provided in this application embodiment;

[0050] Figure 2 A flowchart illustrating another method for determining dynamic geological reserves provided in this application embodiment;

[0051] Figure 3 The pseudo-pressure change curve provided for the embodiments of this application;

[0052] Figure 4 This application provides a graph showing the relationship between the target coefficient and the pseudo-pressure in a double logarithmic coordinate system.

[0053] Figure 5 A schematic diagram of the dynamic geological reserve relationship model provided in the embodiments of this application;

[0054] Figure 6A schematic diagram of the structure of the dynamic geological reserve determination device provided in the embodiments of this application;

[0055] Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0056] 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

[0057] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0058] Currently, in existing technologies, the material balance method only requires two or more shut-in pressure retests to calculate dynamic reserves. However, due to the difficulty in obtaining formation pressure, iterative methods are usually used, resulting in numerous iterations and a large workload. The production decline analysis method uses the Arps decline equation for solution, which is assumed to be suitable for constant bottomhole flowing pressure. However, in oilfield production, when oilfield production conditions remain unchanged, the flowing pressure changes with the formation pressure. Using modern production decline analysis charts for manual fitting results in unavoidable subjective errors.

[0059] This application provides a method, apparatus, equipment, and medium for determining dynamic geological reserves. By considering changes in bottom hole flowing pressure and based on the mass balance formula under abnormal high pressure conditions, a hyperbolic window is introduced to obtain a hyperbolic window decline index under varying bottom hole flowing pressure. This demonstrates that even with changes in bottom hole flowing pressure, the decline index remains solely a function of pressure, and it is still applicable to gas wells with incomplete or missing bottom hole pressure records. Using the decline index, the hyperbolic window decline index is further calculated to construct a dynamic reserve model, thereby using linear analysis to determine the dynamic reserves of the gas reservoir.

[0060] The execution entity of the dynamic geological reserve determination method provided in this application embodiment can be a server. The server can be a mobile phone, tablet, computer, 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 viscosity of natural gas in the gas well at various pressures, the isothermal compressibility coefficient of natural gas in the gas well at various pressures, and the deviation factor of natural gas in the gas well at various pressures; determine the target coefficient and the pseudo-pressure of natural gas in the gas well at various pressures based on the viscosity of natural gas in the gas well at various pressures, the isothermal compressibility coefficient of natural gas in the gas well at various pressures, and the deviation factor of natural gas in the gas well at various pressures; determine the decline index of the gas well during gas well production based on the target coefficient and the pseudo-pressure of natural gas in the gas well at various pressures; determine the hyperbolic window decline index of the gas well under varying bottomhole flowing pressure and the target cumulative gas production of the gas well at different times based on the hyperbolic window decline index of the gas well under varying bottomhole flowing pressure and the target cumulative gas production of the gas well at different times; and determine the dynamic geological reserves of the gas well based on the hyperbolic window decline index of the gas well under varying bottomhole flowing pressure and the target cumulative gas production of the gas well at different times.

[0061] Figure 1 This is a flowchart illustrating a method for determining dynamic geological reserves provided in an embodiment of this application. The execution subject of this method can be a computer, such as... Figure 1 As shown, the method includes the following steps:

[0062] S101. Determine the viscosity of natural gas in the gas well at various pressures, the isothermal compressibility coefficient of natural gas in the gas well at various pressures, and the deviation factor of natural gas in the gas well at various pressures.

[0063] Among them, natural gas viscosity can refer to an index that reflects the viscosity of natural gas. In the embodiments of this application, natural gas viscosity can include the viscosity of natural gas under different pressures. The viscosity of natural gas can be determined by the original formation pressure, bottom hole flow pressure, reservoir temperature and natural gas specific gravity in the PVT (Pressure-Volume-Temperature) parameters.

[0064] The isothermal compressibility coefficient of natural gas can refer to the rate of volume change of natural gas with pressure under isothermal conditions. In the embodiments of this application, the isothermal compressibility coefficient of natural gas can include the isothermal compressibility coefficient of natural gas under different pressures. The isothermal compressibility coefficient of natural gas can be determined by the original formation pressure, bottom hole flow pressure, reservoir temperature and natural gas specific gravity in the PVT parameters.

[0065] The natural gas deviation factor refers to the ratio of real gas to ideal gas. For an ideal gas, the natural gas deviation factor is always 1 at any temperature and pressure. The natural gas deviation factor satisfies the formula:

[0066] ,

[0067] in, This represents the pressure of a real gas. For the volume of the real gas, The thermodynamic temperature of the real gas. The number of moles of gas. Let be the ideal gas constant. =8.314 J·K -1 ·mol -1 .

[0068] In this embodiment of the application, the original formation pressure, bottom hole flow pressure, reservoir temperature, and natural gas specific gravity in the PVT parameters can be obtained by transmitting data through a sensor device connected to the execution body of this embodiment. After obtaining the original formation pressure, bottom hole flow pressure, reservoir temperature, and natural gas specific gravity in the PVT parameters, the natural gas viscosity, natural gas isothermal compressibility coefficient, and natural gas deviation factor at each pressure can be determined by calculation. It can be understood that the natural gas viscosity, natural gas isothermal compressibility coefficient, and natural gas deviation factor are all functions of pressure.

[0069] S102. Based on the natural gas viscosity, isothermal compressibility coefficient, and deviation factor of natural gas in the gas well at various pressures, determine the target coefficient and the pseudo-pressure of natural gas in the gas well at various pressures.

[0070] In this embodiment of the application, the method for determining the target coefficient and the pseudo-pressure of natural gas at various pressures based on the viscosity of natural gas at various pressures, the isothermal compressibility coefficient of natural gas at various pressures, and the deviation factor of natural gas at various pressures may include:

[0071] The initial target coefficients are obtained based on the viscosity of natural gas in the gas well at various pressures and the isothermal compressibility coefficient of natural gas in the gas well at various pressures.

[0072] Based on the initial target coefficient and target parameter, the target coefficient is determined. The target parameter characterizes the influence coefficient of rock compressibility in the gas well on the stored fluid. When the rock is considered incompressible or the rock compressibility is particularly small, the target parameter value is 1.

[0073] Based on the natural gas viscosity and deviation factor of natural gas in the gas well at various pressures, the pseudo-pressure of natural gas in the gas well at various pressures is determined.

[0074] In this embodiment of the application, the target parameter satisfies:

[0075] ,

[0076] This represents the original gas saturation level of the gas reservoir. The isothermal compressibility coefficient of natural gas. The rock compressibility coefficient, This represents the original bound water saturation of the strata. The original formation pressure, This refers to formation pressure.

[0077] The initial target coefficient can refer to the product of the natural gas viscosity and the isothermal compressibility coefficient of natural gas, as used in the embodiments of this application. express, This represents the viscosity of natural gas in a gas well at various pressures. It represents the isothermal compressibility coefficient of natural gas in a gas well under various pressures.

[0078] In this embodiment, the target coefficient is determined based on the initial target coefficient and the target parameter, i.e., target coefficient = .

[0079] Since the density, viscosity, and deviation coefficient of natural gas are functions of pressure, its seepage state differs significantly from that of oil reservoirs. In solving the continuity equation, a pseudo-pressure is introduced to linearize the equations, allowing seepage analysis of gas reservoirs to be conducted using methods similar to those used in oil reservoirs. There is a one-to-one correspondence between the pseudo-pressure function and the actual pressure; that is, given a pressure, the pseudo-pressure function can be determined, and vice versa. Satisfying the formula:

[0080] ,

[0081] in, The simulated pressure of the gas well. For formation pressure, For the viscosity of natural gas, This is the natural gas deviation factor.

[0082] S103. Based on the target coefficient and the pseudo-pressure of natural gas in the gas well at various pressures, determine the decline index of the gas well during gas well production.

[0083] In this embodiment of the application, the method for determining the decline index of a gas well during gas well production based on the target coefficient and the pseudo-pressure of natural gas in the gas well at various pressures may include:

[0084] Determine the ordinate of the double logarithmic curve based on the target coefficient;

[0085] The horizontal axis of the double logarithmic curve is determined based on the pseudo-pressure of natural gas in the gas well under various pressures.

[0086] Based on the ordinate and abscissa of the double logarithmic curve, the decline index of the gas well during gas well production is determined. The decline index of the gas well during gas well production represents the opposite of the slope of the double logarithmic curve.

[0087] In this embodiment of the application, the decline index of the gas well during gas well production satisfies:

[0088] ,

[0089] For the target parameters, For the viscosity of natural gas, The isothermal compressibility coefficient of natural gas. This represents the pseudo-pressure of natural gas in the gas well under various pressure conditions. This refers to formation pressure.

[0090] The ordinate of the double logarithmic curve is... The x-axis of the double logarithmic curve is .

[0091] Among them, the decline index of gas wells during gas well production It can be determined based on the derived formula. In this embodiment of the application, the derivation process is as follows:

[0092] ,

[0093] Among them, the decline index of gas wells during gas well production Satisfies the definition:

[0094] ,

[0095] in, This represents the decline rate of gas well production. Satisfies the definition:

[0096] ,

[0097] in, Natural gas production under standard conditions refers to the production output of a gas well under environmental conditions of 760 mg / mHg pressure and 20°C. The natural gas production under standard conditions satisfies the formula:

[0098] ,

[0099] in, Where J represents the natural gas production under standard conditions, and J is the production capacity index. To simulate pressure, This refers to the bottom-hole flowing pressure of the gas well. This is the pseudo-pressure of natural gas in the gas well under the bottom-hole flowing pressure.

[0100] In this embodiment of the application, the pseudo-pressure of natural gas in the gas well under the bottom hole flowing pressure satisfies:

[0101] ,

[0102] in, To simulate pressure, This is a preset proportionality coefficient used to assume the variation of bottom hole flowing pressure with formation pressure.

[0103] The production capacity index refers to the daily gas production of a gas well under a unit square difference in production pressure. A higher production capacity index indicates higher gas production efficiency. For the circular boundary case (the gas well is a cylindrical circular boundary), the production capacity index... Satisfying the formula:

[0104] ,

[0105] in, For rock permeability, For geological reservoir thickness, , Indicates the seepage radius of the gas reservoir. represents the radius of the gas wellbore, The density of the gas under standard conditions. For a constant value, R=8.314JK - 1 mol -1 , is the reservoir temperature, and MW is the relative molecular mass of the gas.

[0106] Permeability is a physical quantity representing the permeability of a rock, which refers to the rock's ability to allow fluids to pass through.

[0107] Reservoir thickness refers to the thickness of a formation with high permeability and gas storage capacity within a certain depth range.

[0108] Boundary control flow refers to the stage after pressure changes (during gas well production, formation pressure changes and propagates outward from the bottom of the well in the form of pressure waves) reach the boundary of the gas well.

[0109] Among them, the initial decline rate It can be represented as:

[0110] ,

[0111] in, The cross-sectional area of ​​the gas reservoir. This represents the original porosity of the reservoir. , Indicates the seepage radius of the gas reservoir. represents the radius of the gas wellbore, This represents the original gas saturation level of the gas reservoir. For rock permeability, This is a preset proportional coefficient. The viscosity of natural gas under the original formation pressure. The isothermal compressibility coefficient of natural gas under the original formation pressure. These are the target parameters under the original formation pressure.

[0112] Among them, the initial decline rate According to the chain rule, the decline rate of a gas well is used. Definition, mass balance equation, pseudo-pressure Formula, gas well productivity index The formula for the pseudo-pressure of natural gas in a gas well under the bottom hole flowing pressure. Formulas for natural gas production under standard conditions The formula is derived, and the derivation process includes:

[0113] ,

[0114] Therefore, the initial decline rate It can be represented as:

[0115] .

[0116] The mass balance equation can satisfy the following formula:

[0117] ,

[0118] in, The density of natural gas under the original formation pressure. For the target parameters, This represents the natural gas production under standard conditions. The original geological reserves satisfy the formula:

[0119] ,

[0120] in, The cross-sectional area of ​​the gas reservoir. For reservoir thickness, This represents the original porosity of the reservoir. This represents the original gas saturation of the gas reservoir.

[0121] from The formula shows that under varying bottom hole pressure, the proportionality coefficient... For any given value, the decreasing exponent is only a function of pressure. This formula still applies even if the strict invariance condition is not met, or for gas wells with incomplete or missing bottomhole pressure records.

[0122] S104. Based on the decline index of the gas well during gas well production, determine the hyperbolic window decline index of the gas well under varying bottom hole flowing pressure and the target cumulative gas production of the gas well at different times.

[0123] In this embodiment of the application, the method for determining the hyperbolic window decline index of a gas well under varying bottomhole flowing pressure and the target cumulative gas production of the gas well at different times, based on the decline index during gas well production, may include:

[0124] Based on the pseudo-pressure of natural gas in the gas well under various pressures, the decline index of the gas well during production is integrated to obtain the hyperbolic window decline index of the gas well under varying bottom hole pressure. The hyperbolic window decline index of the gas well under varying bottom hole pressure satisfies the following:

[0125] ,

[0126] This represents the original formation pressure of the natural gas. The pseudo-pressure is the pressure under the original formation pressure of natural gas. The final measured bottom hole flowing pressure, For the target parameters, For the viscosity of natural gas, The isothermal compressibility coefficient of natural gas. This represents the pseudo-pressure of natural gas in the gas well under various pressure conditions. Formation pressure;

[0127] Based on the hyperbolic window decline index of the gas well under varying bottomhole flowing pressure, the target cumulative gas production of the gas well at different times is determined, and the target cumulative gas production of the gas well at different times satisfies:

[0128] ,

[0129] The density of natural gas under the original formation pressure. The viscosity of natural gas under the original formation pressure. The isothermal compressibility coefficient of natural gas under the original formation pressure. This represents the original formation pressure of the natural gas. The pseudo-pressure is the pressure under the original formation pressure of natural gas. For a constant value, The target parameters are those under the original formation pressure. This represents the cumulative natural gas production under standard conditions.

[0130] During oilfield extraction, formation pressure changes. When pressure waves propagate from the extraction point to the boundary of the boundary control flow, they enter the boundary control flow stage. For a period of time after entering the boundary control flow stage, there are... Therefore, the decreasing exponent n is approximately constant. This period of time when the decreasing exponent n is approximately constant is called the early stage of the boundary control flow, which is the hyperbolic window stage. Hyperbolic window decreasing exponent It can be obtained through integration.

[0131] Among them, the strict hyperbolic decline requires the decline exponent to be constant, which is only possible in the case of ideal gas. However, in the early stage of the boundary control flow, the decline exponent n is approximately constant, so it is assumed that the hyperbolic decline requirement is met at this time.

[0132] Due to the decreasing exponent This applies to situations with varying bottomhole pressure; therefore, the hyperbolic window decrease index for gas wells under varying bottomhole pressure satisfies:

[0133] ,

[0134] This represents the original formation pressure of the natural gas. The pseudo-pressure is the pressure under the original formation pressure of natural gas. The final measured bottom hole flowing pressure, For the target parameters, For the viscosity of natural gas, The isothermal compressibility coefficient of natural gas. This represents the pseudo-pressure of natural gas in the gas well under various pressure conditions. This refers to formation pressure.

[0135] The final measured bottom hole flowing pressure can refer to the bottom hole flowing pressure actually measured by technicians during the mining process.

[0136] Among them, the cumulative natural gas production under standard conditions Satisfying the formula:

[0137] ,

[0138] in, This represents the initial gas production. To reduce the hyperbolic window decreasing index under varying bottom-hole flow pressure, The initial decrease rate, This represents the natural gas production under standard conditions.

[0139] The initial gas production can refer to the gas production at the initial moment. In this embodiment, it can refer to the gas production on the first day of extraction.

[0140] The initial gas production under standard conditions, such as the gas production on the first day under standard conditions.

[0141] S105. Determine the dynamic geological reserves of the gas well based on the hyperbolic window decline index under varying bottom hole pressure and the target cumulative gas production of the gas well at different times.

[0142] In this embodiment of the application, the method for determining the dynamic geological reserves of a gas well based on the hyperbolic window decline index under varying bottomhole flowing pressure and the target cumulative gas production of the gas well at different times may include:

[0143] Based on the hyperbolic window decline index of a gas well under varying bottom hole pressure, the corresponding value of the standard gas production under the hyperbolic window decline index is obtained.

[0144] Based on the corresponding value of the standard natural gas production under the hyperbolic window decline index and the target cumulative gas production of the gas well at different times, a dynamic geological reserve relationship model is generated.

[0145] Based on the dynamic geological reserve relationship model, the dynamic geological reserves of the gas well are determined.

[0146] The corresponding value of the standard natural gas production under the hyperbolic window decreasing index can be: It satisfies the formula:

[0147] ,

[0148] in, To determine the target cumulative gas production of a gas well at different times. This represents the original geological reserves.

[0149] Therefore, after transforming the formula, the corresponding value of the standard natural gas production under the hyperbolic window decreasing index can be expressed as:

[0150] .

[0151] The dynamic geological reserve relationship model can refer to a coordinate model that uses the target cumulative gas production of a gas well at different times as the horizontal axis and the corresponding value of the standard gas production of natural gas under the hyperbolic window decline index as the vertical axis, and plots the relationship curve between the two.

[0152] The intersection of the relationship curve and the horizontal axis represents the dynamic geological reserves of the gas well.

[0153] Figure 2A flowchart illustrating another dynamic geological reserve determination method provided in this application embodiment is shown below. Figure 2 As shown, the method includes:

[0154] S201. Based on reservoir temperature, natural gas specific gravity, original formation pressure, and bottom hole pressure variation patterns, PVT parameters are used to determine the natural gas viscosity, isothermal compressibility coefficient, and deviation factor under different pressures, thus obtaining the pseudo-pressure. Change curve.

[0155] The reservoir temperature is 93.3℃, ​​the natural gas specific gravity is 0.55, the original formation pressure is 84.8MPa, and the bottom hole pressure variation follows the pattern shown in Table 1.

[0156]

[0157] S202, Based on the target parameters The formula for calculation The target coefficients were obtained in logarithmic coordinates as the formation pressure varied. With simulated pressure The relationship curve.

[0158] The target parameters satisfy the formula:

[0159] ,

[0160] in, The rock compressibility coefficient is equal to , This represents the original formation pressure of the gas reservoir. The original gas saturation of the gas reservoir is equal to 1. The initial water saturation of the gas reservoir is 0. It is the isothermal compressibility coefficient of natural gas.

[0161] S203, Based on the target coefficients in double logarithmic coordinates With simulated pressure The relationship curve was used to determine the decline index of the gas well during the hyperbolic window stage. .

[0162] Among them, the decreasing index of gas wells during the hyperbolic window stage satisfy:

[0163] =0.0847.

[0164] S204, Based on the decline index of the gas well in the hyperbolic window stage Based on production data, linear analysis was used to determine the dynamic reserves of abnormally high-pressure gas reservoirs under varying bottomhole flowing pressure. .

[0165] Among them, the decreasing index of the hyperbolic window stage is calculated. And production data, to determine a dynamic geological reserve relationship model,

[0166] Among them, the target cumulative gas production of the gas well at different times is calculated. Using this as the abscissa of the dynamic geological reserve relationship model, the corresponding value of the standard natural gas production under the hyperbolic window stage decline index is calculated. Using this as the vertical axis of the dynamic geological reserve relationship model, a graph showing the relationship between the two reveals that after the boundary control flow, the two are approximately linearly related, and the intersection of the straight lines on the horizontal axis represents the dynamic geological reserves. .

[0167] Among them, the target cumulative gas production of gas wells at different times Satisfying the formula:

[0168] ,

[0169] The corresponding value of the standard natural gas production under the hyperbolic window stage decline index satisfies the formula:

[0170] .

[0171] Figure 3 The pseudo-pressure variation curve provided in the embodiments of this application represents Figure 2 The pseudo-pressure in step S201 The curve shows the change, where the horizontal axis represents formation pressure. The vertical axis represents pseudo-pressure. .

[0172] Figure 4 This application provides a graph showing the relationship between the target coefficient and the pseudo-pressure on a double logarithmic coordinate system. This graph characterizes... Figure 2 The target coefficients obtained in step S202 in double logarithmic coordinates With simulated pressure The relationship curve, where the ordinate is... The x-axis is .

[0173] Figure 5 This is a schematic diagram of the dynamic geological reserve relationship model provided in the embodiments of this application. The diagram represents... Figure 2 In step S204, the dynamic geological reserve relationship model is shown, where the vertical axis represents the standard natural gas production under the hyperbolic window stage decline index. The horizontal axis represents the target cumulative gas production of the gas well at different times. .

[0174] Figure 6 A schematic diagram of the structure of the dynamic geological reserve determination device provided in the embodiments of this application is shown below. Figure 6 As shown, the dynamic geological reserve determination device 60 may include: a first determination module 601, a second determination module 602, a third determination module 603, a fourth determination module 604, and a dynamic geological reserve determination module 605, wherein,

[0175] The first determining module 601 is used to determine the viscosity of natural gas in the gas well at various pressures, the isothermal compressibility coefficient of natural gas in the gas well at various pressures, and the deviation factor of natural gas in the gas well at various pressures.

[0176] The second determining module 602 is used to determine the target coefficient and the pseudo pressure of natural gas in the gas well at various pressures based on the viscosity of natural gas in the gas well at various pressures, the isothermal compressibility coefficient of natural gas in the gas well at various pressures, and the deviation factor of natural gas in the gas well at various pressures.

[0177] The third determining module 603 is used to determine the decline index of the gas well during gas well production based on the target coefficient and the pseudo pressure of natural gas in the gas well at various pressures.

[0178] The fourth determining module 604 is used to determine the hyperbolic window decline index of the gas well under varying bottom hole pressure and the target cumulative gas production of the gas well at different times, based on the decline index of the gas well during gas well production.

[0179] The dynamic geological reserves determination module 605 is used to determine the dynamic geological reserves of a gas well based on the hyperbolic window decline index under varying bottom hole flowing pressure and the target cumulative gas production of the gas well at different times.

[0180] In this embodiment of the application, the second determining module 602 may also be specifically used for:

[0181] The initial target coefficients are obtained based on the viscosity of natural gas in the gas well at various pressures and the isothermal compressibility coefficient of natural gas in the gas well at various pressures.

[0182] Based on the initial target coefficient and target parameter, the target coefficient is determined. The target parameter characterizes the influence coefficient of rock compressibility in the gas well on the stored fluid. When the rock is considered incompressible or the rock compressibility is particularly small, the target parameter value is 1.

[0183] Based on the natural gas viscosity and deviation factor of natural gas in the gas well at various pressures, the pseudo-pressure of natural gas in the gas well at various pressures is determined.

[0184] In this embodiment of the application, the third determining module 603 can also be specifically used for:

[0185] Determine the ordinate of the double logarithmic curve based on the target coefficient;

[0186] The horizontal axis of the double logarithmic curve is determined based on the pseudo-pressure of natural gas in the gas well under various pressures.

[0187] Based on the ordinate and abscissa of the double logarithmic curve, the decline index of the gas well during gas well production is determined. The decline index of the gas well during gas well production represents the opposite of the slope of the double logarithmic curve.

[0188] In this embodiment of the application, the fourth determining module 604 can also be specifically used for:

[0189] Based on the pseudo-pressure of natural gas in the gas well under various pressures, the decline index of the gas well during production is integrated to obtain the hyperbolic window decline index of the gas well under varying bottom hole pressure. The hyperbolic window decline index of the gas well under varying bottom hole pressure satisfies the following:

[0190] ,

[0191] This represents the original formation pressure of the natural gas. The pseudo-pressure is the pressure under the original formation pressure of natural gas. The final measured bottom hole flowing pressure, For the target parameters, For the viscosity of natural gas, The isothermal compressibility coefficient of natural gas. This represents the pseudo-pressure of natural gas in the gas well under various pressure conditions. Formation pressure;

[0192] Based on the hyperbolic window decline index of the gas well under varying bottomhole flowing pressure, the target cumulative gas production of the gas well at different times is determined, and the target cumulative gas production of the gas well at different times satisfies:

[0193] ,

[0194] The density of natural gas under the original formation pressure. The viscosity of natural gas under the original formation pressure. The isothermal compressibility coefficient of natural gas under the original formation pressure. This represents the original formation pressure of the natural gas. The pseudo-pressure is the pressure under the original formation pressure of natural gas. For a constant value, The target parameters are those under the original formation pressure. This represents the cumulative natural gas production under standard conditions.

[0195] In this embodiment of the application, the dynamic geological reserve determination module 605 can also be specifically used for:

[0196] Based on the hyperbolic window decline index of a gas well under varying bottom hole pressure, the corresponding value of the standard gas production under the hyperbolic window decline index is obtained.

[0197] Based on the corresponding value of the standard natural gas production under the hyperbolic window decline index and the target cumulative gas production of the gas well at different times, a dynamic geological reserve relationship model is generated.

[0198] Based on the dynamic geological reserve relationship model, the dynamic geological reserves of the gas well are determined.

[0199] As can be seen from the above, the dynamic geological reserve determination device of this application embodiment can determine the dynamic geological production of abnormal high-pressure gas reservoirs by considering the changes in bottom hole flowing pressure, avoiding the problem of multiple iterations required by the prior art. The data involved is not complex and the acquisition method is simple, which reduces the difficulty of operation and improves the accuracy of reserve determination.

[0200] Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 7 As shown, the electronic device 70 includes:

[0201] The electronic device 70 may include a processor 701 with one or more processing cores, a memory 702 with one or more computer-readable storage media, a communication component 703, and other components. The processor 701, memory 702, and communication component 703 are connected via a bus 704.

[0202] In the specific implementation process, at least one processor 701 executes computer execution instructions stored in memory 702, causing at least one processor 701 to execute the above-mentioned dynamic geological reserve determination method.

[0203] The specific implementation process of processor 701 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0204] In the above Figure 7In 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 manifested as being executed by a hardware processor, or executed by a combination of hardware and software modules within the processor.

[0205] The memory may include high-speed memory (Random Access Memory, RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0206] 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.

[0207] 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 any of the above-described dynamic geological reserve determination methods.

[0208] For details on the implementation of each of the above operations, please refer to the previous examples, which will not be repeated here.

[0209] 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.

[0210] 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 geological reserve determination methods provided in embodiments of this application.

[0211] The storage medium may include: read-only memory (ROM), random access memory (RAM), disk or optical disk, etc.

[0212] 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.

[0213] Since the instructions stored in the storage medium can execute the steps in any of the dynamic geological reserve determination methods provided in the embodiments of this application, the beneficial effects that any of the dynamic geological reserve determination methods 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.

Claims

1. A method for determining dynamic geological reserves, characterized in that, The method, applied to a dynamic geological reserve determination system, includes: Determine the viscosity of natural gas in the gas well at various pressures, the isothermal compressibility coefficient of natural gas in the gas well at various pressures, and the deviation factor of natural gas in the gas well at various pressures. The initial target coefficient is obtained based on the viscosity of natural gas in the gas well at various pressures and the isothermal compressibility coefficient of natural gas in the gas well at various pressures. Based on the initial target coefficient and target parameter, the target coefficient is determined. The target parameter characterizes the influence coefficient of rock compressibility in the gas well on the stored fluid. The target parameter value is 1 when the rock is considered incompressible or the rock compressibility is particularly small. The target parameter satisfies: ， This represents the original gas saturation level of the gas reservoir. The isothermal compressibility coefficient of natural gas. The rock compressibility coefficient, This represents the original bound water saturation of the strata. The original formation pressure, Formation pressure; Based on the natural gas viscosity and the natural gas deviation factor at various pressures in the gas well, the pseudo pressure of the natural gas at various pressures in the gas well is determined. Based on the target coefficient and the pseudo-pressure of natural gas in the gas well at various pressures, the decline index of the gas well during production is determined; the decline index of the gas well during production satisfies: ， The target parameter is... For the viscosity of natural gas, The isothermal compressibility coefficient of natural gas. For the target coefficient, This represents the pseudo-pressure of the natural gas in the gas well under various pressures. Formation pressure; Based on the pseudo-pressure of natural gas in the gas well under various pressures, the decline index of the gas well during production is integrated to obtain the hyperbolic window decline index of the gas well under varying bottom hole pressure. The hyperbolic window decline index of the gas well under varying bottom hole pressure satisfies the following: ， This represents the original formation pressure of the natural gas. The pseudo-pressure is the pressure under the original formation pressure of natural gas. The final measured bottom hole flowing pressure, The target parameter is... For the viscosity of natural gas, The isothermal compressibility coefficient of natural gas. This represents the pseudo-pressure of the natural gas in the gas well under various pressures. Formation pressure; Based on the hyperbolic window decline index of the gas well under varying bottomhole flowing pressure, the target cumulative gas production of the gas well at different times is determined, and the target cumulative gas production of the gas well at different times satisfies: ， The density of natural gas under the original formation pressure. The viscosity of natural gas under the original formation pressure. The isothermal compressibility coefficient of natural gas under the original formation pressure. This represents the original formation pressure of the natural gas. The pseudo-pressure is the pressure under the original formation pressure of natural gas. For a constant value, The target parameters are those under the original formation pressure. This represents the cumulative natural gas production under standard conditions. Based on the hyperbolic window decline index of the gas well under varying bottom hole pressure, the corresponding value of the standard gas production under the hyperbolic window decline index is obtained; Based on the corresponding value of the standard natural gas production under the hyperbolic window decline index and the target cumulative gas production of the gas well at different times, a dynamic geological reserve relationship model is generated. Based on the dynamic geological reserve relationship model, the dynamic geological reserves of the gas well are determined.

2. The method according to claim 1, characterized in that, Based on the target coefficient and the pseudo-pressure of natural gas in the gas well at various pressures, the decline index of the gas well during gas production is determined, including: Based on the target coefficient, determine the ordinate of the double logarithmic curve; The abscissa of the double logarithmic curve is determined based on the pseudo-pressure of natural gas in the gas well under various pressures. Based on the ordinate and abscissa of the double logarithmic curve, the decline index of the gas well during gas well production is determined, whereby the decline index of the gas well during gas well production represents the opposite of the slope of the double logarithmic curve.

3. A dynamic geological reserve determination device, characterized in that, The device includes: The first determining module is used to determine the viscosity of natural gas in the gas well at various pressures, the isothermal compressibility coefficient of natural gas in the gas well at various pressures, and the deviation factor of natural gas in the gas well at various pressures. The second determining module obtains the initial target coefficient based on the viscosity of natural gas in the gas well at various pressures and the isothermal compressibility coefficient of natural gas in the gas well at various pressures. Based on the initial target coefficient and target parameter, the target coefficient is determined. The target parameter characterizes the influence coefficient of rock compressibility in the gas well on the stored fluid. The target parameter value is 1 when the rock is considered incompressible or the rock compressibility is particularly small. The target parameter satisfies: ， This represents the original gas saturation level of the gas reservoir. The isothermal compressibility coefficient of natural gas. The rock compressibility coefficient, This represents the original bound water saturation of the strata. The original formation pressure, Formation pressure; Based on the natural gas viscosity and the natural gas deviation factor at various pressures in the gas well, the pseudo pressure of the natural gas at various pressures in the gas well is determined. The third determining module is used to determine the decline index of the gas well during gas well production based on the target coefficient and the pseudo-pressure of natural gas in the gas well at various pressures; the decline index of the gas well during gas well production satisfies: ， The target parameter is... For the viscosity of natural gas, The isothermal compressibility coefficient of natural gas. For the target coefficient, This represents the pseudo-pressure of the natural gas in the gas well under various pressures. Formation pressure; The fourth determining module is used to integrate the decline index of the gas well during gas well production based on the pseudo-pressure of natural gas in the gas well at various pressures, to obtain the hyperbolic window decline index of the gas well under varying bottom hole pressure. The hyperbolic window decline index of the gas well under varying bottom hole pressure satisfies the following: ， This represents the original formation pressure of the natural gas. The pseudo-pressure is the pressure under the original formation pressure of natural gas. The final measured bottom hole flowing pressure, The target parameter is... For the viscosity of natural gas, The isothermal compressibility coefficient of natural gas. This represents the pseudo-pressure of the natural gas in the gas well under various pressures. Formation pressure; Based on the hyperbolic window decline index of the gas well under varying bottomhole flowing pressure, the target cumulative gas production of the gas well at different times is determined, and the target cumulative gas production of the gas well at different times satisfies: ， The density of natural gas under the original formation pressure. The viscosity of natural gas under the original formation pressure. The isothermal compressibility coefficient of natural gas under the original formation pressure. This represents the original formation pressure of the natural gas. The pseudo-pressure is the pressure under the original formation pressure of natural gas. For a constant value, The target parameters are those under the original formation pressure. This represents the cumulative natural gas production under standard conditions. The dynamic geological reserves determination module is used to obtain the corresponding value of the standard natural gas production under the hyperbolic window decline index based on the hyperbolic window decline index of the gas well under variable bottom hole flowing pressure. Based on the corresponding value of the standard natural gas production under the hyperbolic window decline index and the target cumulative gas production of the gas well at different times, a dynamic geological reserve relationship model is generated. Based on the dynamic geological reserve relationship model, the dynamic geological reserves of the gas well are determined.

4. 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 claim 1 or 2.

5. 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 claim 1 or 2.

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