A high-temperature and high-pressure water gas dynamic relative permeability test method

Abstract

The application discloses a high-temperature and high-pressure water-gas dynamic phase permeability test method, which comprises the following steps: extracting, cleaning and drying a retrieved core, and then measuring physical parameters of the core; then, the core is saturated in formation water, and then is placed in a core holder; water phase permeability and permeability under the state of bound water are calculated by using Darcy formula; the test device is heated to the original temperature of the formation, and the pressure in the core holder is increased to the original pressure of the formation; formation water in an intermediate container enters the core holder; the water and gas output of the core is tested by gradually reducing the pressure; until the core does not output gas and stably outputs water, relevant data are recorded, and a dynamic water-gas phase permeability curve is determined. The application considers the dynamic change rule of water-gas fluid in rocks when the formation pressure changes in the high-temperature and high-pressure development process, and the determined result is more in line with the actual mining process, so that a more reasonable and reliable dynamic water-gas phase permeability curve test method is provided for the development of high-temperature and high-pressure gas reservoirs.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas exploration and development, and more particularly to a high-temperature and high-pressure water-gas dynamic relative permeability test method. BACKGROUND

[0002] Water-gas relative permeability is a very important basic data in the process of oil and gas field development. At present, the water-gas relative permeability test standard method is to simulate gas (usually nitrogen) and simulated water (usually formation water) under laboratory conditions to obtain the data by using a steady-state method or a non-steady-state method, and the test conditions are normal temperature and low pressure. Since the experiment is generally carried out on a dry core, the influence of bound water on the core is not considered, and the problem of dry experimental gas entering the core and taking away the bound water in the core is not considered. There is a certain error between the data obtained by this method and the actual reservoir rock permeability.

[0003] The characteristics of different methods are as follows: the non-steady-state method is faster than the steady-state method in measuring relative permeability, but the data measurement, analysis and interpretation are more complex than the steady-state method, especially for the core with serious heterogeneity, the non-steady-state method is difficult to obtain reliable relative permeability curve; the steady-state method is generally considered to be suitable for measuring the core with permeability of 0.5mD or more, and since the relative permeability calculation is based on Darcy equation, the result is high in reliability.

[0004] At present, there is a non-steady-state balance water-gas relative permeability test method under reservoir conditions, and the main test steps include: (1) preparing the original formation water sample; (2) measuring the core liquid permeability, establishing the core bound water saturation and measuring the gas permeability of the core under the bound water state; (3) saturating the target core with nitrogen and pressurizing the formation water; (4) after the two phases are balanced, water is used to displace gas at a fixed displacement pressure difference; (5) recording the pressure change and the outlet water and gas production; (6) calculating the relative permeability curve according to the experimental data record. However, under the high-temperature and high-pressure conditions in the formation, when the water-gas is in a balanced state, the interfacial tension of the water-gas is smaller than that of the standard method, and the viscosity also has a large gap, and if the water-gas fluid participating in the seepage does not consider the factor of formation pressure drop, the difference between the experimental results and the seepage law in the actual development process will be large. SUMMARY

[0005] The present application aims to overcome the defect that the existing non-steady-state method is easy to cause large difference in experimental results, and provides a high-temperature and high-pressure water-gas dynamic relative permeability test method. The method considers the dynamic influence of water-gas fluid in the rock when the formation pressure changes in the high-temperature and high-pressure development process, and the measured result is more in line with the actual mining process, thereby providing a convenient and simple, and actually reliable dynamic water-gas relative permeability curve test method for high-temperature and high-pressure gas reservoir development.

[0006] To solve the above technical problems, the technical scheme adopted by the present application is:

[0007] The present application provides a high-temperature and high-pressure water-gas dynamic relative permeability test method, which is completed by a water-gas relative permeability test device, and comprises the following steps:

[0008] Step S1, the physical parameters of the core taken from the field are measured after extraction, oil washing and drying;

[0009] Step S2, the core treated in step S1 is placed in a vacuum environment, and then the vacuum-treated core is saturated in formation water, and the mass m0 of the saturated core is measured;

[0010] Step S3, the core in step S2 is placed in a core holder, a displacement pump is started to input liquid into the core holder, the water flow rate Q at the outlet end of the core holder is measured by a liquid flow meter, the viscosity μ of the water is determined according to the water temperature, the pressure difference Δp between the two ends of the core is measured by a pressure sensor, and the water permeability K is calculated according to the Darcy formula w ;

[0011] Step S4, the displacement pump is operated to displace the core in the core holder at a low speed, and when the weight of the core does not change, the mass m1 of the irreducible water core is measured, and the irreducible water saturation S is calculated based on the mass m0 of the saturated formation water core wi ;

[0012] Step S5, the core treated in step S4 is tested for gas permeability under the condition of irreducible water, and the gas permeability K g( swi ) under the condition of irreducible water is calculated according to the Darcy formula

[0013] Step S6, the control valve of the liquid intermediate container is closed, the heating device is turned on to heat the test device, and the internal and external pressures are gradually increased in a synchronous manner, the internal pressure is used to pressurize the core with humidified gas to simulate the formation pressure, the confining pressure at the confining pump is kept greater than the internal pressure by 5 MPa, and the back pressure at the back pressure pump is kept greater than the internal pressure by 0.5 MPa

[0014] Step S7, after the pressure and temperature of the liquid intermediate container and the core holder are stable and reach the preset value, the control valve of the liquid intermediate container is opened to make the formation water enter the core holder, the confining pressure and the internal pressure are kept unchanged, the pressure sensor is observed, and after the pressure at both ends of the core is stable, the back pressure pump is gradually reduced by a certain pressure, and the water output V w , the gas output V g of the core holder outlet end each time is recorded until the core holder outlet end does not output gas and the water output is stable, and the test is ended.

[0015] The water-gas phase permeability testing device comprises a heating device, a core holder, a gas source, a gas intermediate container, a displacement pump, a liquid intermediate container, a confining pressure pump, a back pressure pump, and pressure sensors, wherein the core holder is located in the heating device, the inlet end of the core holder is connected to the gas source through the gas intermediate container and to the displacement pump through the liquid intermediate container, a gas humidifier is arranged between the gas intermediate container and the gas source to prevent water in the core from being taken away by nitrogen and to ensure that the inlet and outlet of the core are both in a bound water state, thereby avoiding interference with the humidity and water output of the core during displacement, the outlet end of the core holder is connected to the confining pressure pump, the back pressure pump, and gas and liquid flow meters for monitoring the water output V w , the gas output V g of the back pressure pump (i.e., the outlet end of the core holder), and pressure sensors are arranged at both ends of the core holder. The water-gas phase permeability testing device further comprises a monitoring device and an information processing device in communication connection with the pressure sensors, the liquid flow meter, and the gas flow meter, which facilitates real-time tracking and adjustment of the test conditions and test results by the test personnel.

[0016] Further, the gas source in the water-gas phase permeability testing device is a high-pressure gas cylinder containing nitrogen, which has extremely high chemical stability and can avoid reaction between the gas and the core in the testing device.

[0017] Further, in step S1, the target core is extracted, cleaned, and dried, and the target core is measured for the core dry weight m, the length L, the diameter d, the core porosity , the gas permeability K g , the core cross-sectional area A, the core apparent volume V b , and the core pore volume V p .

[0018] Further, in step S3, the core saturated with formation water is loaded into the core holder, an appropriate confining pressure and displacement pressure are applied to the saturated core for liquid permeability testing, and after the test results are stable, the average liquid permeability is recorded as the basis value of the water-gas relative permeability of the core. The calculation formula of the water permeability K w is as follows:

[0019]

[0020] In the formula, Q is the water flow rate at the outlet end of the core holder, μ is the viscosity of water, L is the length of the core, A is the cross-sectional area of the core, A = πd 2 / 4, and Δp is the pressure difference between the two ends of the core.

[0021] Further, in step S4, the core in the saturated water state is replaced with humidified nitrogen at a low speed until the core is in the irreducible water state, which requires a displacement time of more than 2 hours. The core weight does not change, and the irreducible water saturation is calculated based on the dry core weight. wi The calculation formula is as follows:

[0022]

[0023] In the formula, m is the dry core weight measured in step S1, m1 is the core weight in the irreducible water state measured in step S4, and m0 is the core weight saturated with the simulated formation water measured in step S2.

[0024] After the core is in the irreducible water state, the gas permeability of the core in the irreducible water state is tested, and the average gas permeability is recorded as the basic value of the water-gas relative permeability of the core after the test results are stable.

[0025] Further, in step S4, the core holder is replaced with the irreducible water by the displacement pump, which replaces the formation water in the saturated core with the irreducible water at a low speed. The displacement rate should not be too fast, and 0.1 mL / min is appropriate.

[0026] Further, in step S5, the gas permeability K g(swi) in the irreducible water state is calculated according to the Darcy formula.

[0027]

[0028] In the formula, Q0 is the volume flow rate of nitrogen at the outlet end of the core holder measured by the gas flow meter, p0 is the measured atmospheric pressure, μ is the viscosity of the input gas, i.e., nitrogen, L is the core length, A is the cross-sectional area of the core, A = πd 2 / 4, and p1 and p2 are the pressures at the inlet end and the outlet end of the core holder, respectively, which are measured by the pressure sensor.

[0029] Further, the heating device is heated to 120°C to simulate the original formation temperature, and the temperature is maintained until the test is completed. Of course, the temperature can be dynamically adjusted according to the test method and the test purpose.

[0030] Further, in step S6, the pressure is increased to 50 MPa of internal pressure, 55 MPa of confining pressure and 50.5 MPa of back pressure, wherein the internal pressure of 50 MPa represents the original pressure of the formation, the internal pressure is increased by using humidified nitrogen to pressurize the core, the tracking mode of the confining pressure pump is opened, the confining pressure is kept 5 MPa higher than the internal pressure, the tracking mode of the back pressure pump is opened, the back pressure is kept 0.5 MPa higher than the internal pressure, and the liquid intermediate container filled with formation water is radially pressurized to 50 MPa. After the temperature and pressure of the internal fluid of the core reach the set temperature and pressure, the test is started.

[0031] Further, the specific pressure in step S7 is 0.5 MPa, and similarly, 0.5 MPa is one of the preferred values of the pressure reduction, and the specific pressure can be dynamically adjusted according to the test method and the test purpose. The valve on the liquid intermediate container is opened to connect the formation water with the saturated core, and after the system pressure is stabilized, the back pressure is gradually reduced. Each time the back pressure is reduced by 0.5 MPa, until the outlet end of the core holder is not gas, the test is ended. During the test, the differential pressure data of the core at both ends corresponding to the time are recorded, and the water production V w and the gas production V g .

[0032] Compared with the prior art, the beneficial effects of the present application are that the dynamic change rule of the water-gas fluid in the rock is considered when the formation pressure changes in the development process of the high-temperature and high-pressure gas reservoir, the determined result is more in line with the actual production process, and a more reasonable and reliable dynamic water-gas relative permeability test method is provided for the development of the high-temperature and high-pressure gas reservoir. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The flow chart of the water-gas dynamic relative permeability test method of the present application;

[0034] Figure 2 The structural schematic diagram of the water-gas dynamic relative permeability test device of the present application;

[0035] Figure 3 The model diagram of the dynamic relative permeability curve.

[0036] In the drawings:

[0037] 1 - displacement pump; 2 - pressure sensor; 301 - first control valve; 302 - second control valve; 303 - third control valve; 304 - fourth control valve; 4 - liquid intermediate container; 5 - filter; 6 - electric heating wire; 7 - core holder; 8 - heating device; 9 - confining pressure pump; 10 - back pressure pump; 11 - pressurizing pump; 12 - liquid flow meter; 13 - gas flow meter; 14 - gas source; 15 - gas humidifier; 16 - gas intermediate container; 17 - PC end; 18 - liquid collecting device. DETAILED DESCRIPTION

[0038] The application will be further described below in conjunction with the specific embodiments. The accompanying drawings are only used for exemplary description and cannot be understood as a limitation to the patent; in order to better illustrate the embodiments, some components in the drawings can be omitted, enlarged or reduced, and do not represent the actual product size; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings can be omitted.

[0039] The same or similar reference numerals in the drawings of the embodiments of the application correspond to the same or similar components; in the description of the application, it should be understood that if the terms "front", "back", "left", "right" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore the terms describing the positional relationship in the drawings are only used for exemplary description and cannot be understood as a limitation to the patent, for those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances. In addition, the description of "first", "second" and the like in the application is only for the purpose of description and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features.

[0040] Embodiment one:

[0041] This embodiment takes a certain sandstone core as the target core, and carries out water-gas phase permeability test, which is completed by using a water-gas phase permeability test device. As shown in the figure, the test method comprises the following steps: Figure 1

[0042] Step S1, after the core taken from the field is extracted, washed and dried, the physical parameters of the core are measured, the dry weight of the core m = 61.315 g, the length L = 5.821 cm, the diameter d = 2.5 cm, the porosity of the core The gas permeability K g = 6.17 mD is measured, and the cross-sectional area A = 4.92 cm 2 of the core, the apparent volume V b of the core = 28.65 cm 3 , and the pore volume V p of the core = 5.56 cm 3 are calculated;

[0043] Step S2, the core treated in step S1 is placed in a vacuum environment, and then the vacuum-treated core is placed in formation water to be saturated, and the mass m0 of the saturated core is measured = 66.895 g;

[0044] ​Step S3: Place the core sample obtained in step S2 into the core holder 7, drive the displacement pump 1 to input liquid into the core holder 7, and measure the outflow rate Q at the outlet of the core holder 7 using the liquid flow meter 12, which is 0.00893 cm³. 3 / s, based on the water temperature, the water viscosity is estimated to be μ=1. The pressure difference Δp=41.55atm between the two ends of the core is measured by pressure sensor 2. The water phase permeability K is calculated according to Darcy's formula. w =0.255mD;

[0045] Step S4: Run displacement pump 1 to displace the core in core holder 7 at a low displacement rate of 0.1 mL / min. When the core weight no longer changes, measure the mass of the bound water core m1 = 62.915 g. Using the mass of the saturated formation water core m0 = 66.895 g as a benchmark, calculate its bound water saturation as S. wi =28.67%;

[0046] Step S5: Perform gas permeability testing on the core sample after step S4 under bound water conditions, and calculate the gas permeability K under bound water conditions using Darcy's formula. g(swi) =0.846mD;

[0047] Step S6: Close the control valve of the intermediate liquid container 4, i.e., the fourth control valve 304, and turn on the heating device 8 to heat the test device. The internal and external pressures are increased synchronously using a gradual increase method until the internal pressure reaches 50 MPa, the confining pressure reaches 55 MPa, and the back pressure reaches 50.5 MPa. The internal pressure is achieved by pressurizing the core with humidified gas to simulate formation pressure. The confining pressure at the confining pressure pump 9 is maintained at 5 MPa greater than the internal pressure, and the back pressure at the back pressure pump 10 is maintained at 0.5 MPa greater than the internal pressure.

[0048] Step S7: After the pressure and temperature of the intermediate liquid container 4 and the core holder 7 stabilize at the preset values, open the fourth control valve 304 to allow formation water to enter the core holder 7. Maintain the confining pressure of 55 MPa and the internal pressure of 50 MPa unchanged, observe the pressure sensor 2, and after the pressure at both ends of the core stabilizes, gradually reduce the back pressure pump 10 by a specific pressure of 0.5 MPa, and record the water output V at the outlet of the core holder 7 each time. w Air output V g And draw the following table:

[0049]

[0050] The test ended when no more air was emitted from the outlet of the core holder 7 and water flowed steadily. The relative permeability of air, relative permeability of water, and water saturation were recorded and plotted as shown below. Figure 3 The line graph shown.

[0051] SeeFigure 2 The water-gas phase permeability testing device comprises a heating device 8, a core holder 7, a gas source 14, a gas intermediate container 16, a displacement pump 1, a liquid intermediate container 4, a confining pressure pump 9, a back pressure pump 10, and a pressure sensor 2. The core holder 7 is located in the heating device 8. The inlet end of the core holder 7 is connected to the gas source 14 through a third control valve 303 and the gas intermediate container 16, and is connected to the displacement pump 1 through a fourth control valve 304 and the liquid intermediate container 4. A second control valve 302 and a gas humidifier 15 are further arranged between the gas intermediate container 16 and the gas source 14. The gas humidifier 15 can prevent water in the core from being carried away by nitrogen, ensure that the inlet and outlet of the core are both in a stable bound water state, and avoid interfering with the humidity and water output of the core during displacement. The outlet end of the core holder 7 is connected to the confining pressure pump 9 for providing confining pressure to the core holder 7, the back pressure pump 10 for providing back pressure, a liquid flow meter 12, and a gas flow meter 13 for monitoring the water output V w , and the gas output V g of the outlet end of the core holder 7, respectively. Pressure sensors 2 are arranged at both ends of the core holder 7. The water-gas phase permeability testing device further comprises a PC terminal 17 in communication connection with the monitoring device, including the pressure sensors 2, the liquid flow meter 12, and the gas flow meter 13, to facilitate the test personnel to track and adjust the test conditions and test results in real time.

[0052] The displacement pump 1 is connected to a pressure sensor 2. A first control valve 301 is arranged on the output pipeline of the displacement pump 1 for controlling the flow speed of the liquid. When the test starts, the first control valve 301 is opened, and the liquid is delivered from the displacement pump 1 to the liquid intermediate container 4. The liquid intermediate container 4 is also provided with a pressure sensor 2. After the liquid is output from the liquid intermediate container 4, it passes through a filter 5 and a heating wire 6 to enter the core holder 7. On the other side, the core holder 7 is connected to the confining pressure pump 9 and the back pressure pump 10. The back pressure pump 10 is connected to a pressure pump 11. The outlet ends of the confining pressure pump 9 and the pressure pump 11 are both connected to a liquid collection device 18 for collecting and uniformly processing the waste liquid generated in the test.

[0053] The first control valve 301, the second control valve 302, the third control valve 303, and the fourth control valve 304 mentioned in the embodiment can be ordinary manually opened and closed valves. However, in order to facilitate automatic control, electromagnetic valves in communication connection with the PC terminal 17 can also be selected.

[0054] Embodiment Two

[0055] Based on Example 1, in step S3 of this example, a core saturated with formation water is loaded into a core holder 7. Appropriate confining and displacement pressures are applied to test the liquid permeability of the saturated core. After three stable tests, the average liquid permeability is recorded as the baseline value for the relative water-gas permeability of the core. Water phase permeability K w The calculation formula is:

[0056]

[0057] In the formula, Q is the outflow rate at the outlet of the core holder, 0.00893 cm⁻¹ 3 / s, μ is the viscosity of water, 1, L is the length of the core, 5.821cm, A is the cross-sectional area of ​​the core, A=πd 2 / 4 = 4.92cm 2 Δp is the pressure difference between the two ends of the core, 41.55 atm; substituting into the above calculation formula, we get: water phase permeability K w =0.255mD.

[0058] Example 3:

[0059] Based on Example 1 or Example 2, approximately, after the core sample is placed in a bound water state, a gas permeability test is performed on the bound water core sample. After three tests with stable results, the average gas permeability is recorded as the baseline value for the relative water-gas permeability of the core sample. The gas phase permeability K in the bound water state can be calculated using Darcy's formula. g(swi) By transforming Darcy's formula, we get:

[0060]

[0061] In the formula, Q0 is the measured volumetric flow rate of nitrogen at the outlet of the core holder, 0.289 cm⁻¹ 3 / s, p0 is the measured atmospheric pressure, 1 atm, μ is the viscosity of the introduced gas, i.e., nitrogen, 0.018 mPa·s, L is the core length, 5.821 cm, A is the cross-sectional area of ​​the core, A=πd 2 / 4 = 4.92cm 2 p1 and p2 are the inlet and outlet pressures of the core holder, respectively, which are 3.905 atm and 0.02 atm. Substituting these values ​​into the above calculation formula, we obtain the gas phase permeability K under the bound water state. g(swi) =0.846mD.

[0062] In the specific contents of the foregoing specific embodiments, each technical feature can be combined arbitrarily without contradiction. In order to make the description simple, all possible combinations of the foregoing technical features are not described, but as long as the combinations of the technical features do not contradict, they should be considered as the scope of the present disclosure.

[0063] Obviously, the above embodiments of the present application are merely exemplary and are not intended to limit the embodiments of the present application. Based on the above description, other different forms of changes or variations can be made by those of ordinary skill in the art. Here, it is not necessary and impossible to exhaust all the embodiments. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application should be included in the protection scope of the claims of the present application.

Claims

1. A high-temperature and high-pressure water-gas dynamic relative permeability test method, which is completed by means of a water-gas relative permeability test device, the test device comprising a heating device (8), a core holder (7), a gas source (14), a gas intermediate container (16), a displacement pump (1), a liquid intermediate container (4), a confining pressure pump (9), a back pressure pump (10), and pressure sensors (2), wherein the core holder (7) is located in the heating device (8), the inlet end of the core holder (7) is connected to the gas source (14) through the gas intermediate container (16) and connected to the displacement pump (1) through the liquid intermediate container (4), and the outlet end of the core holder (7) is connected to the confining pressure pump (9), the back pressure pump (10), a liquid flow meter (12), and a gas flow meter (13), and the pressure sensors (2) are arranged at both ends of the core holder (7), characterized in that, The method comprises the following steps: Step S1, measuring the physical parameters of the core after extraction, cleaning and drying of the core taken from the field; Step S2, the core treated in step S1 is placed in a vacuum environment, and then the core treated in vacuum is saturated in formation water, and the mass of the saturated core is measured ; Step S3, saturating the mass of step S2 The core is put into the core holder (7), the displacement pump (1) is started to input liquid into the core holder (7), the water flow rate at the outlet end of the core holder (7) is measured by the liquid flow meter (12) Q The differential pressure between the two ends of the core is measured by the pressure sensor (2) The viscosity of the water is determined according to the water temperature μ The water phase permeability is calculated according to the Darcy formula ; Step S4, run the displacement pump (1), low-speed displacement of the core in the core holder (7), when the core weight does not change, the bound water core mass is measured , with the mass of the core saturated with formation water , as the reference, the bound water saturation is calculated as ; Step S5, the core after step S4 is treated to carry out gas measuring permeability test under the bound water state, and the gas phase permeability under the bound water state is calculated according to Darcy formula ; Step S6, closing the control valve of the liquid intermediate container (4), opening the heating device (8) to heat the test device, and gradually increasing the internal and external pressures synchronously, the internal pressure is the internal fluid pressure of the core using humidified gas to simulate the formation pressure, the confining pressure at the confining pressure pump (9) is kept 5 MPa higher than the internal pressure, and the back pressure at the back pressure pump (10) is kept 0.5 MPa higher than the internal pressure; Step S7, after the pressure and temperature of the liquid intermediate container (4) and the core holder (7) are stable and reach the preset value, open the control valve of the liquid intermediate container (4) to make the formation water enter the core holder (7), keep the confining pressure and the internal pressure of the core holder (7) unchanged, observe the pressure sensor (2), and after the pressure at both ends of the core is stable, gradually reduce the same specific pressure by the back pressure pump (10) each time, and record the water output and the gas output at the outlet end of the core holder (7) each time until the outlet end of the core holder (7) does not output gas and stably outputs water, and the test is ended. , until the outlet end of the core holder (7) does not output gas and stably outputs water, and the test is ended.​ 2. The high temperature and high pressure water dynamic relative permeability test method according to claim 1, characterized in that, The gas source (14) contains nitrogen.

3. The high temperature and high pressure water dynamic phase permeability test method according to claim 2, characterized in that, The physical parameters of the core measured in step S1 include the dry weight of the core m , length L , diameter d , core porosity φ , gas measured permeability , and the cross-sectional area of the core A , the apparent volume of the core , and the pore volume of the core are calculated.

4. The high temperature and high pressure water dynamic phase permeability test method according to claim 3, characterized in that, In step S3, the water phase permeability The formula for calculating the water phase permeability is: （1） wherein Q is the water flow rate at the outlet end of the core holder (7), μ is the viscosity of water, L is the length of the core, A is the cross-sectional area of the core, A=πd 2 / 4 , is the differential pressure across the core holder (7).

5. The high temperature high pressure water dynamic phase permeability test method according to any one of claims 2-4, characterized in that, In step S4, the bound water saturation is calculated by the following formula: （2） wherein m M0 is the mass of the core measured in step S1, m M1 is the mass of the core measured in step S4 in the state of irreducible water, m M2 is the mass of the core measured in step S2 saturated with the simulated formation water.

6. The high temperature and high pressure water dynamic phase permeability test method according to claim 5, characterized in that, In step S4, the displacement pump (1) binds the core holder (7) at a water displacement flow rate of 0.1 mL / min.

7. The high temperature and high pressure water dynamic phase permeability test method according to claim 2 or 6, characterized in that, In step S5, the atmospheric pressure is measured according to the environmental conditions p 0, nitrogen viscosity μ N , the volumetric flow rate of nitrogen at the outlet end of the core holder (7) is measured by a gas flow meter (13) Q 0, the pressure at the inlet end of the core holder (7) is measured by a pressure sensor (2) p 1, outlet end pressure p 2, and the gas phase permeability under the bound water state is calculated according to the Darcy formula , the calculation formula is: （3） wherein L is the length of the core, A is the cross-sectional area of the core, A=πd 2 / 4 , d is the diameter of the core.

8. The high temperature and high pressure water dynamic phase permeability test method according to claim 1, characterized in that, In step S6, the heating device (8) is heated to the original formation temperature and continues to step S7 to simulate the formation temperature.

9. The high temperature and high pressure water dynamic phase permeability test method according to claim 1 or 8, characterized in that, In step S6, the internal pressure is increased to the original formation pressure, the internal pressure is the internal fluid pressure of the core using humidified nitrogen, the tracking mode of the confining pressure pump (9) is opened, the confining pressure is kept 5 MPa higher than the internal pressure, the tracking mode of the back pressure pump (10) is opened, the back pressure is kept 0.5 MPa higher than the internal pressure, and the liquid intermediate container (4) containing formation water is pressurized to the original formation pressure.

10. The high temperature and high pressure water dynamic phase permeability test method according to claim 1, characterized in that, The specific pressure in step S7 is 0.5 MPa.

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