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CN-121298552-B - CO2Relative permeability measuring system and method under coexistence condition of water and three phases

CN121298552BCN 121298552 BCN121298552 BCN 121298552BCN-121298552-B

Abstract

The invention belongs to the technical field of permeability measurement, and relates to a relative permeability measurement system and method under the coexistence condition of CO 2 and water. The method comprises the steps of obtaining relative permeability data of gas-phase CO 2 by utilizing a relative permeability experiment of gas-phase CO 2 -water, obtaining relative permeability data of liquid-phase CO 2 by utilizing a relative permeability experiment of liquid-phase CO 2 -water, normalizing three-phase saturation of water-phase, gas-phase CO 2 and liquid-phase CO 2 by combining a STONE model according to the relative permeability data of gas-phase CO 2 and the relative permeability data of liquid-phase CO 2 , and calculating the relative permeability of the water-phase to obtain the three-phase relative permeability of CO 2 liquid-CO 2 gas-water-phase. The method can accurately calculate the three-phase relative permeability of the CO 2 liquid phase-CO 2 gas phase-water phase.

Inventors

  • LI ZETANG
  • FENG GUANHONG
  • XU TIANFU

Assignees

  • 吉林大学

Dates

Publication Date
20260512
Application Date
20251212

Claims (10)

  1. 1. The relative permeability measuring system under the coexistence of CO 2 and water is characterized by comprising a gas supply system, a fluid supply system, a core clamping system, a fluid separation metering system, a data acquisition system and a data analysis system; The gas supply system comprises a gas-phase CO 2 supply system and a liquid-phase CO 2 supply system, and is used for providing liquid-phase CO 2 for the rock core and controlling the injection pressure of the liquid-phase CO 2 ; The fluid supply system is used for providing an aqueous phase working fluid for the core clamping system and isolating and protecting the working fluid from the driving component; The core clamping system is used for fixing the core and regulating and controlling the temperature and confining pressure of the core; The fluid separation metering system is used for separating gas-liquid two-phase fluid permeated from the rock core and metering the gas quantity and the liquid flow respectively; the data acquisition system is used for acquiring the temperature and pressure of the core inlet and outlet and the flow data of each phase; The data analysis system is used for calculating relative permeability data of gas-phase CO 2 and relative permeability data of liquid-phase CO 2 according to the temperature and pressure of the acquired core inlet and outlet and each phase flow data, normalizing the saturation of three-phase CO 2 by combining with the STONE model, and calculating the relative permeability of water phase to obtain the three-phase relative permeability of CO 2 liquid-CO 2 gas-water phase.
  2. 2. The system for measuring relative permeability under CO 2 and water three-phase coexistence according to claim 1, wherein the gas-phase CO 2 supply system comprises a gas source container (101), a gas main valve (102), a first booster pump (103), a gas intermediate container (104), a core front gas pressure regulating valve (105), a first flow controller (106), a humidification tank (107), a gas injection flow control valve (108), a core back gas pressure regulating valve (109) and a back pressure regulator (110); The device comprises a first outlet of an air source container (101) and an inlet of a first booster pump (103) through a gas main valve (102), wherein the outlet of the first booster pump (103) is connected with the inlet of a gas intermediate container (104), one path of the outlet of the gas intermediate container (104) is connected with one end of a first flow controller (106) through a gas pressure regulating valve (105) in front of a rock core, the other path of the outlet of the gas intermediate container is connected with one inlet of a back pressure device (110) through a gas pressure regulating valve (109) behind the rock core, the other end of the first flow controller (106) is connected with the inlet of a humidifying tank (107), the outlet of the humidifying tank (107) is connected with the input end of a rock core clamping system through a gas injection flow control valve (108), the other inlet of the back pressure device (110) is connected with the outlet of the rock core clamping system, and the outlet of the back pressure device (110) is connected with a fluid separation metering system; The liquid-phase CO 2 supply system comprises a liquid main valve (111), a second booster pump (112), a liquid intermediate container (113), a core front liquid pressure regulating valve (114), a second flow controller (115), a first liquid injection flow control valve (116) and a core rear liquid pressure regulating valve (117); the second outlet of the air source container (101) is connected with the inlet of a second booster pump (112) through a liquid main valve (111), the outlet of the second booster pump (112) is connected with the inlet of a liquid intermediate container (113), one path of the outlet of the liquid intermediate container (113) is connected with one end of a second flow controller (115) through a liquid pressure regulating valve (114) in front of the core, the other path of the outlet of the liquid intermediate container is connected with one inlet of a back pressure device (110) through a liquid pressure regulating valve (117) behind the core, and the other end of the second flow controller (115) is connected with the input end of a core clamping system through a first liquid injection flow control valve (116); A first pressure sensor (501) is arranged between the first flow controller (106) and the humidifying tank (107), a second pressure sensor (502) is arranged between the core back gas pressure regulating valve (109) and the back pressure device (110), a third pressure sensor (503) is arranged between the core back gas pressure regulating valve (109) and the back pressure device (110), and a fourth pressure sensor (504) is arranged between the core front liquid pressure regulating valve (114) and the first liquid injection flow control valve (116).
  3. 3. The system for measuring relative permeability under the coexistence of CO 2 and water according to claim 1, wherein the fluid supply system comprises a fluid container (201), a advection pump (202), a displacement fluid intermediate container (203), a working fluid control valve (204), a preheating tank (205) and a second liquid injection flow control valve (206), the fluid container (201) is connected with an inlet of the displacement fluid intermediate container (203) through the advection pump (202), an outlet of the displacement fluid intermediate container (203) is connected with an inlet of the preheating tank (205) through the working fluid control valve (204), and an outlet of the preheating tank (205) is connected with an input end of the core clamping system through the second liquid injection flow control valve (206).
  4. 4. The relative permeability measurement system under the CO 2 and water three-phase coexistence condition according to claim 1, wherein the core holding system comprises a confining pressure pump (301), a confining pressure valve (302), a constant temperature box (303) and a core holder (304), wherein the core holder (304) is arranged in the constant temperature box (303), an inlet of the core holder (304) is connected with an outlet of a gas supply system and an outlet of a fluid supply system, an inlet of the confining pressure pump (301) is connected with one end of the constant temperature box (303), an outlet of the confining pressure pump (301) is connected with the other end of the core holder (304) through the confining pressure valve (302), and a fifth pressure sensor (505) and a first temperature sensor (601) are arranged at the outlet of the core holder (304).
  5. 5. The system for measuring relative permeability under the coexistence of three phases of CO 2 and water according to claim 1, wherein a four-way valve (401) is arranged between an outlet of the gas-phase CO 2 supply system, an outlet of the liquid-phase CO 2 supply system, an outlet of the fluid supply system and an inlet of the core clamping system, and a sixth pressure sensor (506) and a second temperature sensor (602) are arranged between the four-way valve (401) and the core clamping system.
  6. 6. The system for measuring relative permeability under the coexistence of CO 2 and water according to claim 1, wherein the fluid separation metering system comprises a gas-liquid separator (701), a drying cylinder (702), a balance (703) and a gas-liquid flowmeter (704), wherein an output end of the core clamping system is connected with an inlet of the drying cylinder (702) through the gas-liquid separator (701), the gas-liquid separator (701) is arranged on the balance (703), and the gas-liquid flowmeter (704) is arranged at an outlet of the drying cylinder (702).
  7. 7. A relative permeability measurement method based on the relative permeability measurement system under CO 2 and water three-phase coexistence condition according to claim 1, comprising: Performing a relative permeability experiment of gas-phase CO 2 -water by using the relative permeability measurement system under the coexistence condition of the CO 2 and the water according to claim 1 to obtain relative permeability data of gas-phase CO 2 , wherein the relative permeability data of gas-phase CO 2 comprise relative permeability of gas-phase CO 2 , relative permeability of water phase relative to saturation of gas-phase CO 2 and saturation of gas-phase CO 2 ; Performing a relative permeability experiment of liquid-phase CO 2 -water by using the relative permeability measurement system under the coexistence condition of the CO 2 and the water according to claim 1 to obtain relative permeability data of liquid-phase CO 2 , wherein the relative permeability data of liquid-phase CO 2 comprise relative permeability of liquid-phase CO 2 , relative permeability of water phase relative to saturation of liquid-phase CO 2 and saturation of liquid-phase CO 2 ; and normalizing the saturation of the three-phase CO 2 according to the relative permeability data of the gas-phase CO 2 and the relative permeability data of the liquid-phase CO 2 by combining a STONE model, and simultaneously calculating the relative permeability of the water phase to obtain the three-phase relative permeability of the CO 2 liquid-CO 2 gas-water phase.
  8. 8. The method of claim 7, wherein performing the relative permeability experiment of the gas phase CO 2 -water to obtain the relative permeability data of the gas phase CO 2 comprises: Let the water phase saturation of the core be The saturation degree of the gas phase CO 2 is First, the The mass of the water-containing core in the group experiment is The dry core has the mass of The effective pore volume of the core is The simulated formation water density of the saturated core at the measured temperature is The water phase saturation of each set of experimental cores was calculated as: ; The calculated gas phase CO 2 saturation is expressed as: ; let the effective permeability of CO 2 in gas phase be The value of the atmospheric pressure is The flow rate of the gas phase CO 2 is The viscosity of the gaseous CO 2 at the measured temperature was The core length is The core cross-sectional area is The core inlet pressure is The effective permeability of the water phase is The water flow is The viscosity of water at the measured temperature is The core outlet pressure is The relative permeability of the gaseous CO 2 is The effective permeability of the gas phase under the state of bound water is The relative permeability of the aqueous phase with respect to the saturation of the gaseous phase CO 2 is Then: ; ; ; The relative permeability of the aqueous phase with respect to the saturation of the gaseous phase CO 2 was calculated and expressed as: 。
  9. 9. The method of claim 7, wherein performing a relative permeability experiment of liquid phase CO 2 -water to obtain relative permeability data of liquid phase CO 2 comprises: Let the water phase saturation of the core be Liquid phase CO 2 saturation of First, the The mass of the water-containing core in the group experiment is The dry core has the mass of The effective pore volume of the core is The simulated formation water density of the saturated core at the measured temperature is The water phase saturation of each set of experimental cores was calculated as: ; Liquid phase CO 2 saturation was calculated and expressed as: ; Let the effective permeability of liquid phase CO 2 be The flow rate of liquid phase CO 2 is as follows The viscosity of liquid phase CO 2 at the measurement temperature is The core length is The core cross-sectional area is The core inlet pressure is The effective permeability of the water phase is The water flow is The viscosity of water at the measured temperature is The core outlet pressure is The relative permeability of liquid phase CO 2 is The effective permeability of the liquid phase under the state of bound water is The relative permeability of the aqueous phase with respect to the saturation of the liquid phase CO 2 is Then: ; ; ; the relative permeability of the aqueous phase with respect to the saturation of the liquid phase CO 2 was calculated and expressed as: 。
  10. 10. The method of claim 7, wherein normalizing the saturation of three phases of CO 2 while calculating the relative permeability of the aqueous phase to obtain the three-phase relative permeability of CO 2 liquid phase-CO 2 vapor phase-aqueous phase comprises: Let normalized gas phase CO 2 saturation be Normalized liquid phase CO 2 saturation as Normalized water phase saturation as The relative permeability of the gas phase CO 2 is The relative permeability of liquid phase CO 2 is The relative permeability of the water phase is The saturation degree of the gas phase CO 2 is Liquid phase CO 2 saturation of The saturation of the water phase is The saturation of the irreducible water is Then: ; ; ; ; Let the relative permeability of the water phase with respect to the saturation of the gaseous phase CO 2 be The relative permeability of the aqueous phase with respect to the saturation of the liquid phase CO 2 is The relative permeability of the aqueous phase was calculated and expressed as: 。

Description

System and method for measuring relative permeability under CO 2 and water three-phase coexistence condition Technical Field The invention belongs to the technical field of permeability measurement, and particularly relates to a relative permeability measurement system and method under the coexistence condition of CO 2 and water. Background The Carbon Capture, utilization and sequestration engineering of the CCUS (Carbon Capture, utilization and Storage) is used for isolating and sequestration by capturing CO 2 emitted by industry and injecting the CO 2 into deep stratum, and simultaneously realizing synergistic benefits such as enhanced oil gas exploitation, resource recovery promotion and the like, and has irreplaceable effects on relieving global climate abnormality and controlling greenhouse effect exacerbation as the only effective way capable of realizing large-scale Carbon dioxide emission reduction at present. In the practical application of CCUS engineering, CO 2 injected into deep stratum does not always keep a single phase state, and due to factors such as reservoir depth change, pressure and temperature gradient difference, CO 2 undergoes a complex phase change process in the upward migration process (especially when leakage occurs), and finally, CO-exists with stratum water in two phase states of liquid-phase CO 2 and gas-phase CO 2 to form a water-liquid-phase CO 2 -gas-phase CO 2 three-phase seepage system. However, there are substantial differences in the physicochemical properties, migration characteristics, and interactions with formation rocks of liquid phase CO 2 and gas phase CO 2, directly affecting the sequestration stability of CO 2, with the risk of CO 2 leakage. The liquid-phase CO 2 has higher viscosity and density, relatively poorer fluidity, slow migration rate in a reservoir, less influence by buoyancy, tendency to horizontally spread at the lower part of an injection layer, stable and controllable distribution state, easy formation of predictable CO 2 plumes, convenient long-term migration path simulation and management and control, extremely low viscosity and density of the gas-phase CO 2, extremely strong fluidity, remarkable buoyancy effect, quick upward migration, extremely easy leakage along channels such as faults, abandoned wells, stratum cracks and the like, difficult control of distribution, easy occurrence of fingering phenomenon to bypass a low-permeability area, early breakthrough to a non-target horizon, and great increase of the risk of sealing failure. Although the three-phase coexistence system is a typical scene in the CO 2 leakage process, the liquid-phase CO 2 and the gas-phase CO 2 are generally regarded as single CO 2 phases, and the measurement and calculation of the relative permeability are carried out only for the water-CO 2 two-phase system (such as calculating the relative permeability of the liquid phase based on Van Genuchten model and calculating the relative permeability of the gas phase based on Corey model), so that the influence of the intrinsic difference of the two-phase CO 2 on the seepage law is completely ignored, the calculation result cannot truly reflect the three-phase seepage characteristics under the actual working condition, and reliable technical support is difficult to be provided for the preservation safety assessment and the leakage risk prevention and control of the CCUS engineering. Therefore, there is a need to develop a solution capable of distinguishing liquid-phase CO 2 from gas-phase CO 2 and accurately obtaining the relative permeability of water-phase CO 2 -gas-phase CO 2 under three-phase coexistence conditions. Disclosure of Invention In order to solve the technical problems, the invention provides a system and a method for measuring relative permeability under the coexistence condition of CO 2 and water. In a first aspect, the invention provides a relative permeability measurement system under the coexistence of CO 2 and water, which comprises a gas supply system, a fluid supply system, a core clamping system, a fluid separation metering system, a data acquisition system and a data analysis system; The gas supply system comprises a gas-phase CO 2 supply system and a liquid-phase CO 2 supply system, and is used for providing liquid-phase CO 2 for the rock core and controlling the injection pressure of the liquid-phase CO 2; The fluid supply system is used for providing an aqueous phase working fluid for the core clamping system and isolating and protecting the working fluid from the driving component; The core clamping system is used for fixing the core and regulating and controlling the temperature and confining pressure of the core; The fluid separation metering system is used for separating gas-liquid two-phase fluid permeated from the rock core and metering the gas quantity and the liquid flow respectively; the data acquisition system is used for acquiring the temperature and pressure of the core inlet and outlet