A method, device, system and storage medium for evaluating productivity of a salted well

Abstract

The application provides a salt deposition well test productivity evaluation method, device, system and storage medium, and belongs to the field of oil and gas development. The method comprises the following steps: introducing environmental parameters, water component parameters, natural gas parameters and salt component parameters, calculating the to-be-processed gas phase parameters through the environmental parameters, the water component parameters and the natural gas parameters; and obtaining the salt deposition amount per pore volume through salt content analysis of the water component parameters, the environmental parameters, the natural gas parameters, the salt component parameters and the to-be-processed gas-liquid phase parameters. Compared with a conventional well test analysis method, the application fully considers the influence of salt deposition on reservoir physical properties and fluid properties, improves the applicability to salt deposition gas wells, can be applied to productivity evaluation and prediction of salt deposition gas wells, and provides a basis for reasonable productivity evaluation and production system measure adjustment of gas wells.

Description

TECHNICAL FIELD

[0001] The present application mainly relates to the technical field of oil and gas development, and particularly relates to a salt deposition well testing productivity evaluation method, device, system and storage medium. BACKGROUND

[0002] During the operation of a gas well, the temperature and pressure conditions of the wellbore change, causing mineral ions in the formation water to precipitate from the water, condense into salt, and block the near-wellbore area and the wellbore, seriously affecting the normal operation of the gas well.

[0003] Currently, there are two main research directions in the study of the productivity of salt deposition in gas wells. One is to study the impact of salt deposition on productivity through salt deposition mechanism and its impact on reservoir properties. Scholars such as Zuluaga studied the salt deposition mechanism through evaporation of formation water and studied the impact on formation permeability and production performance. Wang Bin conducted a study on the phase characteristics of salt deposition considering high salinity formation water, analyzed the impact of reservoir properties and production performance on formation water evaporation and salt deposition, and analyzed the damage of formation water evaporation and salt deposition to single well productivity and reservoir properties. However, this research direction mainly focuses on the change of reservoir properties caused by salt deposition, which in turn leads to the decrease of productivity, and is mainly a qualitative analysis of productivity, lacking quantitative evaluation of productivity. The other research direction focuses on numerical simulation analysis. Cui Guodong established a comprehensive salt deposition model considering formation water evaporation, NaCl precipitation in water, and changes in reservoir porosity and permeability, calculated the cumulative production of gas wells under different salt deposition schemes through numerical simulation, and studied the change law. Le Duc established a numerical model of salt saturation under radial flow conditions through numerical methods, and studied the productivity loss caused by salt deposition at different positions in the formation. Numerical simulation methods can consider salt deposition to calculate the production change law of gas wells, but this research direction requires many parameters and has great difficulty in field application. For productivity research, existing numerical simulation methods cannot meet the application of field gas well productivity evaluation, and the commonly used productivity test analysis methods have not been studied and analyzed for salt deposition gas wells.

[0004] In field application, productivity testing is an important means to obtain the productivity of a gas well, and the corresponding analytical productivity analysis model and fitting productivity analysis method are particularly important. In the current research on existing productivity evaluation methods, the impact of salt deposition on reservoir properties and the impact of salt deposition on fluid properties are not considered, resulting in poor applicability of conventional productivity evaluation methods for salt deposition gas wells. SUMMARY

[0005] The technical problem to be solved by the present application is to provide a salt deposition well testing productivity evaluation method, device, system and storage medium to solve the problems of the prior art.

[0006] The technical scheme for solving the above technical problem of the present application is as follows: a salt precipitation well test productivity evaluation method, comprising the following steps:

[0007] Import environmental parameters, water component parameters, natural gas parameters and salt component parameters, and calculate the to-be-processed gas phase parameters through the environmental parameters, the water component parameters and the natural gas parameters;

[0008] Perform salt content analysis through the water component parameters, the environmental parameters, the natural gas parameters, the salt component parameters and the to-be-processed gas-liquid phase parameters, and obtain the unit pore volume salt precipitation content;

[0009] Calculate the pseudo-pressure through the unit pore volume salt precipitation content, the salt component parameters, the to-be-processed gas phase parameters and the environmental parameters;

[0010] Construct a productivity model through the pseudo-pressure;

[0011] Import well test productivity data, evaluate the well test productivity data through the productivity model, and obtain the productivity evaluation result of the salt precipitation well test.

[0012] Another technical scheme for solving the above technical problem of the present application is as follows: a salt precipitation well test productivity evaluation device, comprising:

[0013] An import module for importing environmental parameters, water component parameters, natural gas parameters and salt component parameters;

[0014] A flash calculation module for calculating to-be-processed gas phase parameters through the environmental parameters, the water component parameters and the natural gas parameters;

[0015] An analysis module for performing salt content analysis through the water component parameters, the environmental parameters, the natural gas parameters, the salt component parameters and the to-be-processed gas-liquid phase parameters, and obtaining the unit pore volume salt precipitation content;

[0016] A pseudo-pressure calculation module for calculating the pseudo-pressure through the unit pore volume salt precipitation content, the salt component parameters, the to-be-processed gas phase parameters and the environmental parameters;

[0017] A model construction module for constructing a productivity model through the pseudo-pressure;

[0018] The import module is also used for importing well test productivity data;

[0019] A productivity evaluation result obtaining module for evaluating the well test productivity data through the productivity model, and obtaining the productivity evaluation result of the salt precipitation well test.

[0020] Based on the salt deposition well testing productivity evaluation method, the application further provides a salt deposition well testing productivity evaluation system.

[0021] Another technical solution of the application to solve the above technical problems is as follows: a salt deposition well testing productivity evaluation system, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, when the processor executes the computer program, the salt deposition well testing productivity evaluation method is realized.

[0022] Based on the salt deposition well testing productivity evaluation method, the application further provides a computer readable storage medium.

[0023] Another technical solution of the application to solve the above technical problems is as follows: a computer readable storage medium, the computer readable storage medium stores a computer program, when the computer program is executed by a processor, the salt deposition well testing productivity evaluation method is realized.

[0024] The application has the beneficial effects that: the to-be-processed gas phase parameters are calculated through the environmental parameters, the water component parameters and the natural gas parameters, the unit pore volume salt precipitation amount is analyzed through the water component parameters, the environmental parameters, the natural gas parameters, the salt component parameters and the salt amount of the to-be-processed gas liquid phase parameters, the pseudo pressure is calculated through the unit pore volume salt precipitation amount, the salt component parameters, the to-be-processed gas phase parameters and the environmental parameters, the productivity model is constructed through the pseudo pressure, the productivity evaluation result of the salt deposition well testing is obtained through the evaluation of the well testing productivity data of the productivity model, the influence of the salt deposition on the reservoir physical properties and the fluid properties is fully considered, the applicability to the salt deposition gas well is improved, and the application can be applied to the productivity evaluation and prediction of the salt deposition gas well, thereby providing a basis for the reasonable productivity evaluation and production system measure adjustment of the gas well. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 A flowchart of a salt deposition well testing productivity evaluation method provided by an embodiment of the application is shown in the figure;

[0026] Figure 2 A vertical well pseudo steady-state productivity model calculation result graph provided by an embodiment of the application is shown in the figure;

[0027] Figure 3 A vertical well pseudo steady-state productivity model calculation result graph provided by an embodiment of the application is shown in the figure;

[0028] Figure 4 A vertical well pseudo steady-state productivity model calculation result graph provided by an embodiment of the application is shown in the figure;

[0029] Figure 5 A horizontal well pseudo steady-state productivity model calculation result graph provided by an embodiment of the application is shown in the figure;

[0030] Figure 6This is a graph showing the fitting calculation results of measured gas production well test data provided in an embodiment of the present invention;

[0031] Figure 7 This is a graph showing the fitting calculation results of measured gas injection well productivity test data provided in an embodiment of the present invention;

[0032] Figure 8 This is a module block diagram of a salt-bearing well production capacity evaluation device provided in an embodiment of the present invention. Detailed Implementation

[0033] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0034] Figure 1 This is a flowchart illustrating a method for evaluating the productivity of salt-bearing well tests, as provided in an embodiment of the present invention.

[0035] like Figure 1 As shown, a method for evaluating the productivity of salt-bearing well tests includes the following steps:

[0036] Environmental parameters, water component parameters, natural gas parameters, and salt component parameters are imported, and the gas phase parameters to be treated are calculated using the environmental parameters, water component parameters, and natural gas parameters.

[0037] Salt content analysis was performed using the water component parameters, environmental parameters, natural gas parameters, salt component parameters, and gas-liquid phase parameters to be treated to obtain the amount of salt precipitated per unit pore volume.

[0038] The pseudo-pressure is calculated using the amount of salt precipitated per unit pore volume, the salt composition parameters, the parameters of the gas phase to be treated, and the environmental parameters.

[0039] A capacity model is constructed using the simulated pressure.

[0040] Import well test production data, evaluate the well test production data using the production model, and obtain the production evaluation results of the salt-forming well test.

[0041] It should be understood that natural gas parameters refer to the parameters of a mixture of hydrocarbons and non-hydrocarbons. The hydrocarbons are mainly composed of methane, ethane, propane, butane, pentane, hexane, and heavy hydrocarbon components, while the non-hydrocarbons are mainly composed of nitrogen, carbon dioxide, and hydrogen sulfide components.

[0042] It should be understood that different types of capacity evaluation equations are constructed based on the pseudo-pressure calculation method that takes salt deposition into account (i.e., the pseudo-pressure) to evaluate and predict capacity.

[0043] Specifically, the process of constructing the productivity model through the pseudo-pressure, evaluating the well test productivity data through the productivity model, and obtaining the productivity evaluation result of the salt precipitation well test includes:

[0044] In order to consider the influence of salt precipitation on reservoir properties and the influence on fluid properties, the productivity equation in the form of pseudo-pressure is adopted, wherein the pseudo-pressure adopts the constructed pseudo-pressure function;

[0045] The productivity evaluation equation includes an analytical productivity evaluation equation and a fitting productivity evaluation method. According to the actual needs of the field, a corresponding productivity evaluation method is selected to calculate and predict productivity. When the reservoir property parameters are known without conducting a productivity test, the analytical productivity evaluation method is selected. Different productivity models can be divided according to different well types and flow types. The productivity model is directly calculated by giving the reservoir property parameters, and then the productivity of the gas well is evaluated, and the future productivity is predicted by giving the prediction pressure.

[0046] When the test data (i.e., the well test productivity data) are obtained by conducting a field productivity test, the fitting productivity evaluation method is selected for analysis. The productivity test method includes a one-point productivity test, a system test, an isochronal test, and a modified isochronal test. The corresponding productivity fitting equation includes an exponential productivity equation and a binomial productivity equation, wherein the pressure form adopts a pseudo-pressure form. The productivity equation coefficients and the open flow capacity are obtained by fitting the test data (i.e., the well test productivity data). Meanwhile, the future productivity is predicted by giving the prediction pressure.

[0047] Specifically, the productivity evaluation equation includes an analytical productivity evaluation equation and a fitting productivity evaluation method. The analytical productivity evaluation equation is obtained by establishing an analytical expression of the productivity model. The productivity model is directly calculated by giving the reservoir thickness, permeability, skin factor, and other parameters. Different productivity models can be divided according to different well types and flow types. Different well types include vertical wells, horizontal wells, fractured vertical wells, and multi-stage fractured horizontal wells. Different flow types include steady-state seepage, pseudo-steady-state seepage, and unsteady-state seepage. The productivity equation is directly calculated through the analytical productivity model, and then the productivity is evaluated. The future productivity can be predicted by giving the prediction pressure.

[0048] The productivity evaluation model of the vertical well pseudo-steady state is:

[0049]

[0050] At this time, the coefficients of the binomial productivity equation can be obtained as follows:

[0051] The laminar flow coefficient is:

[0052] The turbulent flow coefficient is:

[0053] The straight well unsteady productivity evaluation model is:

[0054]

[0055] Wherein:

[0056] The horizontal well pseudo-steady productivity equation is:

[0057]

[0058] The fractured straight well pseudo-steady productivity equation is:

[0059]

[0060] In the formula: q is the flow rate, m 3 / d; p r is the average formation pressure, MPa; p wf is the bottom hole pressure, MPa; K i is the original permeability, mD; φ is the porosity; C t is the comprehensive compressibility, MPa -1 ; γ is the Euler constant; μ is the gas viscosity, mPa·s; h is the effective thickness, m; r e is the supply radius, m; r w is the wellbore radius, m; C A is the shape factor; S is the skin factor; D is the non-Darcy flow coefficient, 1 / (m 3 / d); p sc is the pressure at standard condition, MPa; T sc is the temperature at standard condition, K; T is the reservoir temperature, K; L is the horizontal well length, m; x f is the fracture half-length, m; t is the production time, h.

[0061] The productivity evaluation method is mainly applicable to productivity test analysis, and the fitting analysis is carried out according to the field productivity test. The productivity test methods mainly include one-point productivity test, system test, isochronal test and modified isochronal test. The corresponding productivity fitting equations mainly include exponential productivity equation and binomial productivity equation. The parameters and open flow capacity are obtained by test data fitting, and the pressure form adopts pseudo-pressure form.

[0062] The binomial productivity equation is:

[0063] ψ(p r )-ψ(p wf )=Aq+Bq 2

[0064] The exponential productivity equation is:

[0065]

[0066] Different production capacity testing methods correspond to different fitting calculation methods. For the binomial production capacity equation:

[0067] ①One-point method

[0068] You need to input the equation coefficient B value, and then calculate the A value based on the pressure and flow rate measured by the one-point method using the following formula:

[0069]

[0070] ②System well testing

[0071] The binomial productivity equation can be transformed into:

[0072]

[0073] By inputting at least two system test pressure and flow data, fit By obtaining the slope and intercept of the straight line with respect to q, the coefficients A and B of the equation can be calculated.

[0074] ③ Isochronous well testing

[0075] Similar to system well testing, by inputting at least two system test pressure and flow rate data, a fitting process is performed. The linear relationship with q yields the slope of the line, from which the equation coefficient B is obtained. However, the other coefficient of the equation needs to be calculated using the stable pressure and flow rate obtained from the time-delay test.

[0076]

[0077] ④ Correction of isochronous well testing

[0078] Similar to isochronous well testing, fitting is performed by inputting at least two system test pressure and flow rate data. The difference is that it requires inputting the pressure at the end of production and the pressure at the end of shut-in. The slope of the straight line is obtained from the linear relationship with q. The coefficient B of the equation is obtained from the slope. The other coefficient of the equation needs to be calculated from the stable pressure and flow rate of the time delay test.

[0079] In the formula: p r —Mean formation pressure, MPa; p test For testing pressure, MPa; p extend For delayed testing pressure, MPa; p wf To test the final pressure at the production end, MPa; p ws To test the shut-in pressure, MPa; q test To test traffic, m 3 / d;q extend To delay the test traffic, m 3 / d; A is the laminar flow coefficient, MPa 2 / (mPa s) / (m 3 / d); B is the turbulent flow coefficient, MPa 2 / (mPa s) / (m 3 / d) 2 .

[0080] For the exponential deliverability equation:

[0081] ① One-point method

[0082] The equation coefficient n value needs to be input, and then the C value is calculated according to the pressure and flow rate of the one-point method test through the following formula:

[0083]

[0084] ② System test

[0085] The exponential deliverability equation can be converted to:

[0086]

[0087] Let The equation is converted to:

[0088] log(ψ(p r )-ψ(p wf ))=Alog q+B

[0089] By inputting at least two system test pressure and flow data, the straight line relationship between log(ψ(p r )-ψ(p wf )) and log q is fitted to obtain the slope and intercept, and then the equation coefficient C=10 -Bn .

[0090] ③ Isochronal test

[0091] Similar to the system test, by inputting at least two system test pressure and flow data, the straight line relationship between log(ψ(p r )-ψ(p wf )) and log q is fitted to obtain the slope, and then the equation coefficient is calculated by the slope The difference is that the other coefficient of the equation needs to be calculated by the stable pressure and flow rate of the delay test:

[0092]

[0093] ④ Modified isochronal test

[0094] Similar to isochronal test, at least two system test pressure and flow data are inputted for fitting, but the difference is that the end point pressure of production and the end point pressure of shut-in need to be inputted, and the linear relationship of log(ψ(p ws )-ψ(p wf )) and log q is fitted to obtain the slope of the straight line, and the equation coefficient is calculated by the slope Another coefficient of the equation needs to be calculated by the stable pressure and flow of the delay test.

[0095] In the above formula, p r is the average formation pressure, MPa; p test is the test pressure, MPa; p extend is the delay test pressure, MPa; p wf is the end point pressure of test production, MPa; p ws is the end point pressure of test shut-in, MPa; q test is the test flow, m 3 / d; q extend is the delay test flow, m 3 / d; C is the deliverability coefficient, (m 3 / d) / (MPa 2 / (mPa·s)) n ; and n is the index.

[0096] In the above embodiment, the to-be-processed gas phase parameters are calculated by the environmental parameters, the water component parameters and the natural gas parameters, the salt precipitation amount per unit pore volume is obtained by the salt component parameters, the to-be-processed gas phase parameters and the environmental parameters, the pseudo pressure is calculated by the salt precipitation amount per unit pore volume, the salt component parameters, the to-be-processed gas phase parameters and the environmental parameters, the productivity model is constructed by the pseudo pressure, and the productivity evaluation result of the salt precipitation well testing is obtained by the evaluation of the well testing productivity data by the productivity model. The influence of the salt precipitation on the reservoir physical property and the fluid property is fully considered, the applicability to the salt precipitation gas well is improved, the productivity evaluation and prediction of the salt precipitation gas well can be applied, and the basis for the reasonable productivity evaluation and the production system measure adjustment of the gas well is provided.

[0097] Optionally, as one embodiment of the present application, the water component parameters include the amount of substance of water component substances, the salinity of brine, the water component eccentricity factor, the water component critical temperature, the water component critical pressure and the water component binary interaction coefficient, the natural gas parameters include the amounts of substance of multiple natural gas substances, multiple natural gas eccentricity factors, multiple natural gas critical temperatures, multiple natural gas critical pressures and multiple natural gas binary interaction coefficients, and the environmental parameters include the environmental pressure and the environmental temperature,

[0098] The process of calculating the to-be-processed gas phase parameters by the environmental parameters, the water component parameters and the natural gas parameters includes:

[0099] flashing the water component amount of substance, the brine salinity, the water component acentric factor, the water component critical temperature, the water component critical pressure, the water component binary interaction coefficient, the environmental pressure, the environmental temperature, a plurality of the natural gas amount of substance, a plurality of the natural gas acentric factor, a plurality of the natural gas critical temperature, a plurality of the natural gas critical pressure, and a plurality of the natural gas binary interaction coefficient to obtain a gas phase acentric factor, a water component gas phase mole fraction, and a plurality of natural gas liquid phase mole fractions;

[0100] The gas phase parameters to be processed include the gas phase acentric factor, the water component gas phase mole fraction, and a plurality of the natural gas liquid phase mole fractions.

[0101] It should be understood that based on the gas-liquid thermodynamic equilibrium theory, the two-phase flash equation is used to calculate the liquid phase mole fraction n w , the gas phase mole fraction n g , the mole fraction of component i in the liquid phase x i , the mole fraction of component i in the gas phase y i (i.e. the water component gas phase mole fraction or the natural gas gas phase mole fraction), the liquid phase acentric factor Z w , the gas phase acentric factor Z g at different temperatures T and pressures p.

[0102] Specifically, the two-phase flash equation is as follows:

[0103] The mass conservation equation is as follows:

[0104] n w +n g = 1 (1)

[0105] The component i mass conservation equation is as follows:

[0106] n w x i +n g y i = z i (2)

[0107] The component i fugacity in the liquid phase and the gas phase is equal as follows:

[0108] f wi = f gi (3)

[0109] The constraint equation is as follows:

[0110]

[0111] For the liquid phase fugacity, the following formula is satisfied:

[0112]

[0113] For the gas phase fugacity, the following applies:

[0114]

[0115] The intermediate variables in Equations 1-6 are defined as follows:

[0116]

[0117]

[0118]

[0119]

[0120]

[0121]

[0122]

[0123] In Equations 1-6: T represents temperature (i.e., the ambient temperature), K; p represents pressure (i.e., the ambient pressure), MPa; z i represents the amount of substance of component i (i.e., the water component amount of substance or the natural gas amount of substance), kmol; c sw represents the salinity of the brine (i.e., the brine salinity), kg / m 3 ; ω i represents the acentric factor of component i (i.e., the water component acentric factor or the natural gas acentric factor); T ci represents the critical temperature of component i (i.e., the water component critical temperature or the natural gas critical temperature), K; p ci represents the critical pressure of component i (i.e., the water component critical pressure or the natural gas critical pressure), MPa; k 0ij represents the binary interaction coefficient of component i with component j in the natural gas (i.e., the water component binary interaction coefficient or the natural gas binary interaction coefficient), i≠j, 1≤i≤N-1, 1≤j≤N-1; R represents the gas constant, MPa·m 3 / (kmol·K); n w represents the total amount of substance in the liquid phase, kmol; n g represents the total amount of substance in the gas phase, kmol; x i represents the mole fraction of component i in the liquid phase; y irepresents the mole fraction of component i in the gas phase (i.e. the water component gas phase mole fraction or the natural gas gas phase mole fraction); Z w represents the liquid phase deviation factor; Z g represents the gas phase deviation factor; f wi represents the fugacity of component i in the liquid phase, Pa; f gi represents the fugacity of component i in the gas phase, MPa; A w , A g represents the liquid phase, gas phase equation of state coefficients, respectively; F w , F g represents the liquid phase, gas phase equation of state coefficients, respectively; a i represents the equation of state parameter of component i, MPa·m 6 / kmol 2 ; b i represents the equation of state parameter of component i, m 3 / kmol; (aα) wm , (aα) gm represents the liquid phase, gas phase equation of state parameter functions, MPa·m 6 / kmol 2 ; ψ wi , ψ gi represents the liquid phase, gas phase equation of state parameter functions, MPa·m 6 / kmol 2 ; b wm , b gm represents the liquid phase, gas phase equation of state parameter functions, m 3 / kmol; T ri represents the reduced temperature of component i; α i represents the temperature correction coefficient of component i; τ i represents the bias factor function of component i; k ij represents the binary interaction coefficient of component i and component j; subscript i represents the i th component, i = 1, i = 2, …, i = N-4, i = N-3, i = N-2, i = N-1, i = N respectively corresponding to methane, ethane, …, N-4 alkane, nitrogen, carbon dioxide, hydrogen sulfide, water; subscript j represents the j th component; N represents the total number of components.

[0124] In the above embodiment, the to-be-processed gas phase parameters are calculated through the environmental parameters, the water component parameters and the natural gas parameters, which lays a foundation for subsequent data processing, fully considers the influence of salt precipitation on reservoir properties and fluid properties, improves the applicability to salt precipitation gas wells, and provides a basis for reasonable productivity evaluation and production system measure adjustment of gas wells.

[0125] Optionally, as an embodiment of the present application, the water component parameters further comprise a water component molar mass and a liquid water density, the natural gas parameters further comprise a plurality of natural gas molar masses, the salt component parameters comprise an initial brine concentration, a brine solubility and a solid salt density,

[0126] The salt content analysis by the water component parameters, the environmental parameters, the natural gas parameters, the salt component parameters and the to-be-treated gas-liquid phase parameters comprises:

[0127] The gas phase parameter calculation by the gas phase deviation factor, the liquid water density, the water component gas phase molar fraction, the water component molar mass, the environmental pressure, the environmental temperature, the plurality of natural gas molar masses and the plurality of natural gas gas phase molar fractions comprises a gas phase solubility and a gas phase viscosity, and the equation set is:

[0128]

[0129] wherein λ is a gas phase molar mass, y N is a water component gas phase molar fraction, y i is an i-th natural gas gas phase molar fraction, M N is a water component molar mass, M i is an i-th natural gas molar mass, ρ g is a gas phase density, p is an environmental pressure, Z g is a gas phase deviation factor, R is a gas constant, T is an environmental temperature, R wg is a gas phase solubility, ρ w is a liquid water density, μ g is a gas phase viscosity.

[0130] The initial saturation parameter is introduced, and a formation water volume of the initial saturation parameter and the gas phase solubility is calculated to obtain a target formation water volume;

[0131] A salt volume is calculated by the initial brine concentration, the solid salt density, the liquid water density and the initial saturation parameter;

[0132] A unit pore volume precipitated salt content is calculated by the salt volume, the target formation water volume, the brine solubility, the solid salt density and the liquid water density.

[0133] It should be understood that the gas phase deviation factor and the gas phase viscosity are also referred to as gas phase fluid property parameters.

[0134] Specifically, the molar fraction y i of component i in the gas phase at different temperatures and pressures is obtained, and the gas phase deviation factor Zg Further, the gas phase molar mass, the gas phase density, the water vapor solubility in the gas phase, the gas phase viscosity can be obtained, and the formulas are as follows:

[0135]

[0136] In formula 7: M i represents the molar mass of component i, kg / kmol; M N represents the molar mass of the water component (i.e., the water component molar mass), kg / kmol; p w represents the liquid phase water density, kg / m 3 ; Z g , y i are obtained from formulas 1-6; R, T, p are described in formulas 1-6; R wg represents the water vapor solubility in the gas phase (i.e., the gas phase solubility); p g represents the gas phase viscosity affected by salt precipitation (i.e., the gas phase viscosity), mPa·s; p g represents the gas phase density affected by salt precipitation, kg / m 3 ; l represents the molar mass of the gas phase, kg / kmol.

[0137] In the above embodiment, the unit pore volume salt precipitation amount is obtained by analyzing the water component parameters, the environment parameters, the natural gas parameters, the salt component parameters, and the salt amount of the gas-liquid phase to be treated, precise data is provided, the applicability to the salt precipitation gas well is improved, the productivity evaluation prediction of the salt precipitation gas well can be applied, and a basis is provided for the reasonable productivity evaluation and production system measure adjustment of the gas well.

[0138] Optionally, as an embodiment of the present application, the original saturation parameters include an original gas saturation and an original water saturation,

[0139] The process of calculating the formation water volume of the original saturation parameters and the gas phase solubility to obtain the target formation water volume includes:

[0140] The original gas saturation and the formation water volume of the original water saturation and the gas phase solubility are calculated by the first formula to obtain the target formation water volume, and the first formula is:

[0141]

[0142] Wherein, V w is the target formation water volume, S w0 is the original water saturation, S g0 is the original gas saturation, R wg is the gas phase solubility.

[0143] Specifically, the water vapor amount is calculated according to the solubility, assuming that the pore volume V p is 1 m 3 The following formula is used:

[0144]

[0145] In the formula, V eva is the water vapor volume, m 3 ; V g0 is the original natural gas volume, m 3 ; S g0 is the original gas saturation, a decimal; R wg is obtained from formula 7; T and p are described in formulas 1-6.

[0146] The remaining formation water (i.e., the target formation water volume) and the new water saturation are calculated according to the water vapor amount, as follows:

[0147]

[0148] S w = V w / V p = V w

[0149] In the formula, V w0 is the original formation water volume, m 3 ; V eva is described in formula 8; V w is the remaining formation water volume (i.e., the target formation water volume), m 3 ; S w is the current water saturation, a decimal; S w0 is the original water saturation, a decimal; S g0 is described in formula 8; R wg is obtained from formula 7; T and p are described in formulas 1-6.

[0150] In the above embodiment, the target formation water volume is calculated by the first formula, the original gas saturation, and the formation water volume of the original water saturation and the gas phase solubility, which provides accurate data, improves the applicability to salt deposition gas wells, and can be applied to the productivity evaluation and prediction of salt deposition gas wells.

[0151] Optionally, as one embodiment of the present application,

[0152] The original saturation parameter includes the original water saturation, and the process of calculating the salt volume from the original brine concentration, the solid salt density, the liquid water density, and the original saturation parameter includes:

[0153] The salt volume is calculated by a second formula, the original salt water concentration, the solid salt density, the liquid phase water density, and the original water saturation, the second formula being:

[0154]

[0155] wherein V s0 is the salt volume, S w0 is the original water saturation, p w is the liquid phase water density, p s is the solid salt density, x s0 is the original salt water concentration.

[0156] It should be understood that the original salt content (i.e. the salt volume) is calculated according to the original concentration and the water saturation, assuming that the formation water does not migrate and the salt does not evaporate, and the salt content at any place in the formation remains unchanged, as follows:

[0157]

[0158] wherein V w0 is explained in formula 9; x s0 is the original salt concentration in water (i.e. the original salt water concentration), %; S w0 is explained in formula 9; p w represents the liquid phase water density, kg / m 3 ; p s represents the solid salt density, kg / m 3 ; V s0 is the original salt volume (i.e. the salt volume), m 3 .

[0159] In the above embodiment, the salt volume is calculated by a second formula, the original salt water concentration, the solid salt density, the liquid phase water density, and the original water saturation, which provides accurate data and improves the applicability to salted gas wells, and can be applied to productivity evaluation and prediction of salted gas wells.

[0160] Optionally, as one embodiment of the present application,

[0161] The process of calculating the salt amount precipitated per unit pore volume by the salt volume, the target formation water volume, the salt water solubility, the solid salt density, and the liquid phase water density comprises:

[0162] The salt amount precipitated per unit pore volume is calculated by a third formula, the salt volume, the target formation water volume, the salt water solubility, the solid salt density, and the liquid phase water density, the third formula being:

[0163] C s = p w Vw (x s -x equ ),

[0164] wherein,

[0165] wherein, C s is the precipitated salt quantity per unit pore volume, V w is the target formation water volume, p w is the liquid phase water density, x s is the target brine concentration, x equ is the brine solubility, p s is the solid salt density, V s0 is the salt volume.

[0166] Specifically, the salt concentration (i.e., the target brine concentration) is calculated according to the remaining formation water (i.e., the target formation water volume) and the salt content (i.e., the salt volume), as follows:

[0167]

[0168] wherein, S w0 is explained in equation 9; x s0 is explained in equation 10; S g0 is explained in equation 8; R wg is obtained from equation 7; T, p are explained in equations 1-6. p w , p s , V s0 is explained in equation 10; V w is explained in equation 9; x s is the current salt concentration in the formation water (i.e., the target brine concentration), %;

[0169] The current salt concentration in the formation water (i.e., the target brine concentration) is compared with the solubility of salt in water x equ (i.e., the brine solubility), when x s > x equ , the salt precipitates, and the precipitated salt quantity at this time is calculated as follows:

[0170]

[0171] wherein, V w is explained in equation 9; x s is explained in equation 11; p w is explained in equation 10; S w0 is explained in equation 9; x s0 is explained in equation 10; S g0 is explained in equation 8; R wgFrom equation 7; T, p are explained in equation 1-6. x equ Solubility of salt in water (i.e. the salt water solubility), %; C s Salt amount per unit pore volume, mol / m 3 .

[0172] In the above embodiment, the salt amount per unit pore volume is calculated by the third formula, the salt volume, the target formation water volume, the salt water solubility, the solid salt density, and the liquid phase water density. Compared with the conventional productivity evaluation method, the present application comprehensively considers the influence of salt precipitation in the gas well on the reservoir porosity and permeability, and the influence on the gas deviation factor, viscosity and other fluid properties, and builds a pseudo-pressure calculation method and a productivity evaluation and prediction method suitable for the salt precipitation gas well, which can better evaluate and predict the relatively reliable productivity meeting the production conditions of the salt precipitation gas well.

[0173] Optionally, as one embodiment of the present application,

[0174] The salt component parameter includes the amount concentration of the salt substance, the to-be-treated gas phase parameter includes the gas deviation factor and the gas phase viscosity, and the environment parameter includes the environment pressure,

[0175] The process of calculating the pseudo-pressure by the salt amount per unit pore volume, the salt component parameter, the to-be-treated gas phase parameter, and the environment parameter includes:

[0176] The salt precipitation amount porosity is calculated by the fourth formula, the salt amount per unit pore volume, and the amount concentration of the salt substance, and the fourth formula is:

[0177]

[0178] Wherein, φ s is the salt precipitation amount porosity, C s is the salt amount per unit pore volume, c s is the amount concentration of the salt substance;

[0179] The rock compression coefficient, the original porosity, the original formation pressure, and the original permeability are imported, and the target permeability is calculated by the fifth formula, the rock compression coefficient, the environment pressure, the original porosity, the original formation pressure, the original permeability, and the salt precipitation amount porosity, and the fifth formula is:

[0180]

[0181] Wherein, φ = (φ i - φ s )[1 + C f (p-p i )].

[0182] wherein K is the target permeability, K i is the original permeability, φ is the target porosity, φ i is the original porosity, φ s is the salt precipitation porosity, C f is the rock compressibility, p is the ambient pressure, p i is the original formation pressure;

[0183] A pseudo-pressure is calculated by a sixth equation, the gas phase viscosity, the gas deviation factor, the original permeability, the target permeability, and the pseudo-pressure of the ambient pressure, the sixth equation being:

[0184]

[0185] wherein ψ (p) is the pseudo-pressure, K is the target permeability, K i is the original permeability, p is the ambient pressure, μ g is the gas phase viscosity, Z g is the gas deviation factor.

[0186] It is understood that the salt precipitation occupying pore space according to the unit pore volume of salt precipitation is calculated as the salt precipitation porosity, i.e., the salt precipitation porosity, as follows:

[0187]

[0188] wherein φ s is the salt precipitation porosity, %; C s is explained in equation 12; c s is the amount concentration of the salt substance, mol / m 3 .

[0189] Specifically, the reservoir property change caused by salt precipitation mainly includes the change of porosity and the change of permeability, the change formula of porosity is calculated according to the pore space occupied by the amount of salt precipitation, the change formula of permeability (i.e., the target permeability) is calculated according to the relationship formula of porosity (i.e., the target porosity) and permeability (i.e., the original permeability), as follows:

[0190] φ = (φ i - φ s )[1 + C f (p - p i )] (14)

[0191]

[0192] wherein φ s is explained in equation 13; C f is the rock compressibility, MPa -1 ; φi Original porosity (%); φ represents current porosity (%); p i p is the original formation pressure, MPa; p is the current formation pressure, MPa; K i is the original permeability, mD; K is the permeability, mD.

[0193] Specifically, based on the pseudo-pressure concept introduced by Al-Hussainy and Ramey, a pseudo-pressure function considering salt deposition is constructed, replacing the fluid property parameters calculated by flash evaporation. Simultaneously, a permeability ratio is added to the integral of the pseudo-pressure function to incorporate the influence of reservoir properties on the pseudo-pressure, as shown in the following equation:

[0194]

[0195] In the formula, K, K i As explained in Formula 15; ψ represents the pseudo-pressure, in MPa. 2 / (mPa·s); φ, φ i As explained in Equation 15; p has been explained in Equations 1-6; μ g Z represents the gas viscosity (i.e., the gas phase viscosity), in mPa·s. g The gas deviation coefficient is denoted as .

[0196] In the above embodiments, the pseudo-pressure is calculated by the amount of salt precipitated per unit pore volume, salt composition parameters, gas phase parameters to be treated, and environmental parameters. This fully considers the impact of salt formation on reservoir properties and fluid properties, improves the applicability to salt-forming gas wells, and can be applied to the production capacity evaluation and prediction of salt-forming gas wells, providing a basis for the reasonable production capacity evaluation of gas wells and the adjustment of production system measures.

[0197] Optionally, as another embodiment of the present invention, the present invention includes the following steps:

[0198] S1: Considering salt deposition, a gas-liquid flash evaporation calculation model is constructed to calculate the molar composition of gas and liquid components. Combined with fluid property calculation formulas, the variation law of gas-liquid fluid properties is determined. S2: Based on the flash evaporation calculation results and combined with the principle of material balance, the amount of salt deposition is calculated, and the variation law of reservoir properties caused by salt deposition is determined according to the amount of salt deposition. S3: Based on the variation law of reservoir properties and fluid property changes, a pseudo-pressure calculation method considering salt deposition is determined. S4: Based on the pseudo-pressure calculation method considering salt deposition, different types of production capacity evaluation equations are constructed for production capacity evaluation and prediction. S5: A software module for production capacity evaluation and prediction of salt-deposited gas wells is developed. This invention can be applied to the production capacity evaluation and prediction of salt-deposited gas wells, providing a basis for reasonable production capacity evaluation and adjustment of production system measures for gas wells.

[0199] Optionally, as another embodiment of the present application, the present application obtains the gas phase deviation factor, gas phase viscosity and water vapor solubility in the gas phase at different temperatures and pressures by using the salinity of the brine and the equation of state of the natural gas and water component for phase equilibrium flash calculation.

[0200] Optionally, as another embodiment of the present application, the present application programs the flash calculation method, salt deposition amount calculation method, pseudo-pressure calculation method and productivity evaluation model calculation method to form corresponding software modules. The software modules are used for the calculation and evaluation of productivity under different conditions, and provide theoretical support for the reasonable productivity evaluation, productivity prediction and production system adjustment of the salt deposition gas well.

[0201] Optionally, as another embodiment of the present application, the present application forms a new flash calculation method to obtain the gas-liquid phase diagram by correcting the water component coefficient and introducing the binary interaction coefficient of hydrocarbons and brine based on the multi-component equilibrium model and the equation of state, considering the salt deposition of the gas well, which can be applied to the productivity evaluation of the salt deposition gas well and other well testing analysis or numerical simulation analysis.

[0202] Compared with the conventional productivity evaluation method, the present application comprehensively considers the influence of the salt deposition of the gas well on the reservoir porosity and permeability and the influence on the fluid properties such as the gas deviation factor and viscosity, and builds a pseudo-pressure calculation method and a productivity evaluation and prediction method suitable for the salt deposition gas well, which can better evaluate and predict the relatively reliable productivity meeting the production conditions of the salt deposition gas well.

[0203] Optionally, as another embodiment of the present application, the present application determines the variation law of the fluid properties and the variation law of the reservoir physical property parameters considering the salt deposition by using the gas-liquid flash calculation method considering the salt deposition, and forms a gas well productivity evaluation and prediction method considering the salt deposition by defining a new pseudo-pressure calculation method to include the salt deposition in the pseudo-pressure calculation.

[0204] Optionally, as another embodiment of the present application, as shown in Figure 2 , the present application and the conventional pseudo-pressure calculation method not considering the salt deposition are respectively used for calculation, and the basic parameters are calculated: the gas saturation is 70%, the water saturation is 30%, the salinity of the formation water is 300000 mg / L, the amount-of-substance concentration of the salt is 37000 mol / m 3 , the rock compressibility is 4x10 -4 MPa -1 , the original porosity is 0.1, the original permeability is 5 mD, the skin factor is 1, the original formation pressure is 38.62 MPa, the supply radius is 100 m, the wellbore radius is 0.07855 m, the shape factor is 31.62, the reservoir thickness is 69 m, and the formation temperature is 120 degrees Celsius. The component composition after the calculation of the straight well pseudo-steady-state productivity model is shown in Table 1.

[0205]

[0206] Table 1

[0207] As Figure 2 shown, from the calculation results, it can be seen that the productivity curves considering salt precipitation and not considering salt precipitation have great difference, and the relative error of the open flow capacity finally calculated is up to 33%.

[0208] Alternatively, as another embodiment of the present application, as shown in Figure 3 , the present application and the conventional pseudo-pressure calculation method not considering salt precipitation are respectively used for calculation, and the basic parameters are calculated: gas saturation 70%, water saturation 30%, formation water salinity 300000 mg / L, salt molar concentration 37000 mol / m 3 , rock compressibility 4x10 -4 MPa -1 , production time 0.1 h, comprehensive compressibility 1x10 -3 MPa -1 , initial porosity 0.1, initial permeability 5 mD, skin factor 1, initial formation pressure 38.62 MPa, supply radius 100 m, wellbore radius 0.07855 m, shape factor 31.62, reservoir thickness 69 m, formation temperature 120 degrees Celsius. The component composition after calculation of the straight well unsteady productivity model is shown in Table 2:

[0209]

[0210] Table 2

[0211] As Figure 3 shown, from the calculation results, it can be seen that the productivity curves considering salt precipitation and not considering salt precipitation have great difference, and the relative error of the open flow capacity finally calculated is up to 56%.

[0212] Alternatively, as another embodiment of the present application, as shown in Figure 4 , the present application and the conventional pseudo-pressure calculation method not considering salt precipitation are respectively used for calculation, and the basic parameters are calculated: gas saturation 70%, water saturation 30%, formation water salinity 300000 mg / L, salt molar concentration 37000 mol / m 3 , rock compressibility 4x10 -4 MPa -1, initial porosity 0.1, initial permeability 5 mD, skin factor 1, initial formation pressure 38.62 MPa, supply radius 100 m, wellbore radius 0.07855 m, fracture half-length 50 m, shape factor 31.62, reservoir thickness 69 m, formation temperature 120 degrees Celsius. The component composition is shown in Table 3, which is the component composition after calculation of the fractured vertical well pseudo-steady productivity model:

[0213]

[0214] Table 3

[0215] As shown in Figure 4 , it can be seen from the calculation results that the productivity curve considering salt deposition is quite different from the productivity curve not considering salt deposition, and the relative error of the open flow capacity finally calculated is up to 41%.

[0216] Alternatively, as another embodiment of the present application, as shown in Figure 5 , the present application and the conventional pseudo-pressure calculation method not considering salt deposition are respectively used for calculation, and the basic parameters are calculated: gas saturation 70%, water saturation 30%, formation water salinity 300000 mg / L, salt molar concentration 37000 mol / m 3 , rock compressibility 4 x 10 -4 MPa -1 , initial porosity 0.1, initial permeability 5 mD, skin factor 1, initial formation pressure 38.62 MPa, supply radius 100 m, wellbore radius 0.07855 m, horizontal well length 100 m, shape factor 31.62, reservoir thickness 69 m, formation temperature 120 degrees Celsius. The component composition is shown in Table 4, which is the component composition after calculation of the horizontal well pseudo-steady productivity model:

[0217]

[0218] Table 4

[0219] As shown in Figure 5 , it can be seen from the calculation results that the productivity curve considering salt deposition is quite different from the productivity curve not considering salt deposition, and the relative error of the open flow capacity finally calculated is up to 48%.

[0220] Alternatively, as another embodiment of the present application, as shown in Figure 6 , the measured bottom hole pressures are respectively 18.919, 19.836, 18.968, 18.202, 19.781 MPa, the measured production amounts are respectively 388065, 292128, 344760, 394721, 276408 m 3 / d, and the average formation pressure is 22.3 MPa.

[0221] The basic parameters for pseudo-pressure calculation are: gas saturation 70%, water saturation 30%, formation water salinity 300000 mg / L, salt molar concentration 37000 mol / m 3 , rock compressibility 4*10 -4 MPa -1 , original porosity 0.1, original permeability 5 mD, formation temperature 120 degrees Celsius. The component composition is shown in Table 5, which is the component composition after fitting calculation of the actual gas production well deliverability test data:

[0222]

[0223]

[0224] Table 5

[0225] As shown in Figure 6 , the conventional pressure square form and the pseudo-pressure form of the present application are used for fitting calculation respectively, and from the calculation results, it can be seen that the deliverability curve fitting result of the pseudo-pressure form considering salt deposition has certain difference from the pressure square form not considering salt deposition, but the difference is small, and the relative error of the finally calculated open flow capacity is 4%.

[0226] Alternatively, as another embodiment of the present application, as shown in Figure 7 , the actual bottom hole pressure is 33.973, 34.220, 34.455, 34.674 MPa respectively, the actual injection amount is 162135, 266917, 361855, 433478 m 3 / d, and the average formation pressure is 33.711 MPa.

[0227] The basic parameters for pseudo-pressure calculation are: gas saturation 70%, water saturation 30%, formation water salinity 300000 mg / L, salt molar concentration 37000 mol / m 3 , rock compressibility 4*10 -4 MPa -1 , original porosity 0.1, original permeability 5 mD, formation temperature 120 degrees Celsius. The component composition is shown in Table 6, which is the component composition after fitting calculation of the actual gas injection well deliverability test data:

[0228]

[0229] Table 6

[0230] As shown in Figure 7As shown, the conventional pressure square form and the pseudo pressure form of the present application are respectively used for fitting calculation, and from the calculation results, it can be seen that the pseudo pressure form considering salt deposition has certain difference with the pressure square form not considering salt deposition, but the difference is small, and the relative error of the finally calculated maximum injection amount is 7%.

[0231] Figure 8 A module block diagram of a salt deposition well testing productivity evaluation device is provided for an embodiment of the present application.

[0232] Optionally, as another embodiment of the present application, as shown in a salt deposition well testing productivity evaluation device includes: Figure 8

[0233] An import module is used for importing environmental parameters, water component parameters, natural gas parameters and salt component parameters.

[0234] A flash calculation module is used for calculating to-be-processed gas phase parameters through the environmental parameters, the water component parameters and the natural gas parameters.

[0235] An analysis module is used for salt amount analysis through the water component parameters, the environmental parameters, the natural gas parameters, the salt component parameters and the to-be-processed gas-liquid phase parameters to obtain unit pore volume precipitation salt amount.

[0236] A pseudo pressure calculation module is used for calculating pseudo pressure through the unit pore volume precipitation salt amount, the salt component parameters, the to-be-processed gas phase parameters and the environmental parameters.

[0237] A model construction module is used for constructing a productivity model through the pseudo pressure.

[0238] The import module is further used for importing well testing productivity data.

[0239] A productivity evaluation result obtaining module is used for evaluating the well testing productivity data through the productivity model to obtain a productivity evaluation result of salt deposition well testing.

[0240] Optionally, another embodiment of the present application provides a salt deposition well testing productivity evaluation system, including a memory, a processor and a computer program stored in the memory and executable on the processor, when the processor executes the computer program, a salt deposition well testing productivity evaluation method as described above is realized. The system can be a computer system.

[0241] Optionally, another embodiment of the present application provides a computer readable storage medium, the computer readable storage medium stores a computer program, when the computer program is executed by a processor, a salt deposition well testing productivity evaluation method as described above is realized. ​

[0242] It should be noted that the relationship terms, such as first and second, etc., are merely used to differentiate one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such a process, method, article or device.

[0243] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the above-described device and unit can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0244] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative, for example, the division of units is only a logical function division, and actual implementation can have another division manner, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0245] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, that is, they can be located in one place, or they can be distributed on multiple network units. According to actual needs, some or all of the units can be selected to achieve the purpose of the embodiment of the present application.

[0246] In addition, each functional unit in each embodiment of the present application can be integrated into a processing unit, or each unit can exist physically independently, or two or more units can be integrated into one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0247] The integrated unit, if implemented in the form of a software function unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or say the part that contributes to the prior art, or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0248] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method of evaluating the productivity of a salted well, characterized in that, The method comprises the following steps: importing environment parameters, water component parameters, natural gas parameters and salt component parameters, calculating the to-be-processed gas-liquid phase parameters through the environment parameters, the water component parameters and the natural gas parameters; conducting salt content analysis through the water component parameters, the environment parameters, the natural gas parameters, the salt component parameters and the to-be-processed gas-liquid phase parameters to obtain the unit pore volume precipitated salt content; calculating the pseudo-pressure through the unit pore volume precipitated salt content, the salt component parameters, the to-be-processed gas-liquid phase parameters and the environment parameters; constructing a productivity model through the pseudo-pressure; importing well testing productivity data, evaluating the well testing productivity data through the productivity model to obtain a productivity evaluation result of the salted well testing; the water component parameters comprise water component molar quantity, salt water salinity, water component eccentricity factor, water component critical temperature, water component critical pressure, water component binary interaction coefficient, water component molar mass and liquid phase water density, the natural gas parameters comprise multiple natural gas molar quantities, multiple natural gas eccentricity factors, multiple natural gas critical temperatures, multiple natural gas critical pressures, multiple natural gas binary interaction coefficients and multiple natural gas molar masses, the environment parameters comprise environment pressure and environment temperature, and the salt component parameters comprise original salt water concentration, salt water solubility and solid salt density; the process of conducting salt content analysis through the water component parameters, the environment parameters, the natural gas parameters, the salt component parameters and the to-be-processed gas-liquid phase parameters to obtain the unit pore volume precipitated salt content comprises: conducting gas phase parameter calculation on the gas phase eccentricity factor, the liquid phase water density, the water component gas phase molar fraction, the water component molar mass, the environment pressure, the environment temperature, multiple natural gas molar masses and multiple natural gas gas phase molar fractions to obtain gas phase solubility and gas phase viscosity; importing original saturation parameters, the original saturation parameters comprising original gas saturation and original water saturation, calculating the formation water volume of the original gas saturation and the original water saturation and the gas phase solubility through a first formula to obtain a target formation water volume, the first formula being: where V w is the volume of the target formation water, S w0 is the initial water saturation, S g0 is the initial gas saturation, R wg is the gas phase solubility; the original saturation parameters comprise original water saturation, calculating a salt volume through a second formula, the original salt water concentration, the solid salt density, the liquid phase water density and the original water saturation, the second formula being: where V s0 is the salt volume, S w0 is the initial water saturation, p w is the liquid water density, p s is the solid salt density, x s0 is the initial salt water concentration; calculating the unit pore volume precipitated salt content through a third formula, the salt volume, the target formation water volume, the salt water solubility, the solid salt density and the liquid phase water density, the third formula being: C s = p w V w (x s - x equ ), wherein where C s is the salt concentration in the pore volume, V w is the target formation water volume, p w is the liquid water density, x s is the target brine concentration, x equ is the brine solubility, p s is the solid salt density, V s0 is the salt volume; the salt component parameters comprise salt molar quantity concentration, the to-be-processed gas-liquid phase parameters comprise gas deviation coefficient and gas phase viscosity, and the environment parameters comprise environment pressure, calculating the salted content porosity through a fourth formula, the unit pore volume precipitated salt content and the salt molar quantity concentration, the fourth formula being: where φ s is the salt content porosity, C s is the salt content per unit pore volume, c s is the salt mass concentration; By importing the rock compressibility coefficient, initial porosity, initial formation pressure, and initial permeability, the target permeability is calculated using Equation 5, the rock compressibility coefficient, the environmental pressure, the initial porosity, the initial formation pressure, the initial permeability, and the salt deposition porosity. Equation 5 is as follows: where φ = (φ i -φ s )[1 + C f (p-p i )], where K is the target permeability, K i is the original permeability, φ is the target porosity, φ i is the original porosity, φ s is the salt content porosity, C f is the rock compressibility, p is the ambient pressure, p i is the original formation pressure; The pseudo-pressure is calculated using the sixth equation, the gas phase viscosity, the gas deviation coefficient, the original permeability, the target permeability, and the ambient pressure. The sixth equation is: where ψ(p) is the pseudo-pressure, K is the target permeability, K i is the original permeability, p is the environmental pressure, μ g is the gas phase viscosity, Z g is the gas deviation factor.

2. The method for evaluating the productivity of salt-bearing well tests according to claim 1, characterized in that, The process of calculating the gas-liquid phase parameters to be treated using the environmental parameters, the water component parameters, and the natural gas parameters includes: The two-phase flash evaporation equation is used to perform flash evaporation calculations on the amount of substance of the water component, the salinity of the brine, the eccentricity factor of the water component, the critical temperature of the water component, the critical pressure of the water component, the binary interaction coefficient of the water component, the ambient pressure, the ambient temperature, the amount of substance of multiple natural gas components, the eccentricity factor of multiple natural gas components, the critical temperature of multiple natural gas components, the critical pressure of multiple natural gas components, and the binary interaction coefficient of multiple natural gas components, to obtain the gas phase deviation factor, the gas phase mole fraction of the water component, and the liquid phase mole fraction of multiple natural gas components. The gas-liquid phase parameters to be processed include the gas phase deviation factor, the gas phase mole fraction of the water component, and multiple gas phase mole fractions.

3. The method of claim 2, wherein, The gas phase parameters, namely the gas phase deviation factor, the liquid phase water density, the gas phase mole fraction of the water component, the molar mass of the water component, the ambient pressure, the ambient temperature, multiple molar masses of natural gas, and multiple molar fractions of natural gas, are calculated using a set of equations to obtain the gas phase solubility and gas phase viscosity. The set of equations is as follows: where λ is the gas phase molar mass, y N is the water component gas phase mole fraction, y i is the ith natural gas gas phase mole fraction, M N is the water component molar mass, M i is the ith natural gas molar mass, p g is the gas phase density, p is the environmental pressure, Z g is the gas phase deviation factor, R is the gas constant, T is the environmental temperature, R wg is the gas phase solubility, p w is the liquid phase water density, p g is the gas phase viscosity.

4. The salted well test deliverability evaluation device is applied to the salted well test deliverability evaluation method of claim 1, characterized in that, include: The import module is used to import environmental parameters, water component parameters, natural gas parameters, and salt component parameters. The flash evaporation calculation module is used to calculate the gas-liquid phase parameters to be treated using the environmental parameters, the water component parameters, and the natural gas parameters. The analysis module is used to perform salt content analysis using the water component parameters, the environmental parameters, the natural gas parameters, the salt component parameters, and the gas-liquid phase parameters to be treated, to obtain the amount of salt precipitated per unit pore volume; The pseudo-pressure calculation module is used to calculate the pseudo-pressure using the amount of salt precipitated per unit pore volume, the salt composition parameters, the gas-liquid phase parameters to be treated, and the environmental parameters. The model building module is used to build a production capacity model based on the simulated pressure; The import module is also used to import well test production data; The production capacity evaluation result acquisition module is used to evaluate the well test production capacity data through the production capacity model to obtain the production capacity evaluation result of the salt-forming well test.

5. A salt-up test well deliverability evaluation system comprising a memory, a processor, and a computer program stored in the memory and operable on the processor, wherein, When the processor executes the computer program, it implements the salt-bearing well production capacity evaluation method as described in any one of claims 1 to 3.

6. A computer-readable storage medium storing a computer program, the computer program comprising instructions that, when executed by a computer, cause the computer to perform the method of any one of claims 1 to 5. When the computer program is executed by the processor, it implements the salt-bearing well productivity evaluation method as described in any one of claims 1 to 3.

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