Osmotic healing experimental system and method of use thereof

Abstract

The present invention provides a permeation healing experiment system and a method for using the same. The permeation healing experiment system includes: a pore fluid device, a sample chamber device, and a confining pressure device. The pore fluid device includes a plurality of fluid containers connected in parallel, each of the plurality of fluid containers contains a pore fluid inside, the sample chamber device includes a pressure vessel for containing a sample, and the confining pressure device includes a pressure pump, wherein the fluid container in the pore fluid device is connected to the pressure vessel in the sample chamber device through a pipeline, and the confining pressure device applies pressure to the inside of the pressure vessel through the pressure pump, wherein the pore fluid flows out of the fluid container and then flows into the inside of the pressure vessel in the sample chamber device, and the pressure pump provides the pressure vessel with a certain pressure. The permeation healing experiment system can continuously provide the sample chamber device with pore fluid, so as to realize the uninterrupted permeation healing experiment on the rock.

Description

Technical Field

[0001] The invention relates to an infiltration healing experiment system and a use method thereof, and in particular to an infiltration healing experiment system for performing an infiltration healing experiment on rocks and a use method thereof. Background Art

[0002] Earthquake activity has a cyclical characteristic. Fluids play an important role in all stages of earthquake activity. In the post-earthquake and inter-earthquake periods, the interaction between fluids and rocks will gradually heal the fault zone and restore the strength of the fault. As the fault heals, the fluid pressure in the fault zone will also evolve. The change of fluid pressure in the fault zone has important dynamic significance.

[0003] In recent years, both field fault observations and laboratory research have confirmed the healing process of post-earthquake faults and their connection with earthquake cycles. It is mainly manifested in the following two mutually constrained processes: first, physical and chemical effects such as dissolution precipitation, cementation and water-rock reaction make the fault gradually heal and the strength gradually recover; second, as the cracks heal, the permeability of the fault zone gradually decreases, and the high-pressure fluid gradually accumulates and causes the effective pressure to decrease. When the differential stress and fluid pressure reach a certain critical value, the fault becomes unstable. The combined effect of the two leads to the periodic recurrence of earthquakes. Therefore, studying the healing process of the post-earthquake fault zone, obtaining the permeability data of the post-earthquake fault zone and its evolution over time are of great significance for judging the recovery of fault strength and constraining the earthquake cycle and its recurrence. The permeability healing experimental system is a special experimental device used in the laboratory for fault healing experimental research.

[0004] Therefore, it is necessary to provide a penetration healing experiment system capable of conducting a penetration healing experiment on rocks and a method for using the same. Summary of the invention

[0005] In view of the above problems in the prior art, the present invention is proposed. The present invention aims to provide an osmotic healing experimental system, which includes: a pore fluid device, a sample chamber device and a confining pressure device, wherein the pore fluid device includes a plurality of fluid containers connected in parallel, each of the plurality of fluid containers contains pore fluid, the sample chamber device includes a pressure container for containing samples, and the confining pressure device includes a pressure pump, wherein the fluid container in the pore fluid device is connected to the pressure container in the sample chamber device through a pipeline, and the confining pressure device applies pressure to the interior of the pressure container through the pressure pump, wherein the pore fluid flows out of the fluid container and then flows into the interior of the pressure container in the sample chamber device, and the pressure pump provides a liquid with a certain pressure to the pressure container.

[0006] Preferably, the porous fluid device also includes a gas cylinder, a pressure regulating valve, a water tank, a water pump and a plurality of stop valves, the water tank and the water pump are connected by a pressure pipeline, the liquid pumped out by the water pump is respectively transported to the inside of each of the fluid containers through the pressure pipeline, the gas cylinder and the pressure regulating valve are connected by a pressure pipeline, the gas in the gas cylinder is transported to the inside of each of the fluid containers through the pressure pipeline, and a plurality of stop valves are arranged on the pressure pipeline for controlling the switches of the water pump, the gas cylinder and the pressure container.

[0007] Preferably, the gas stored in the gas cylinder is carbon dioxide gas, and the gas stored in the water pump is water or mineralized fluid.

[0008] Preferably, each of the multiple fluid containers includes a cylindrical fluid container body, an upper container end cap for sealing the upper end opening of the fluid container body, a lower container end cap for sealing the lower end opening of the fluid container body, a gas outlet and a gas inlet formed on the upper container end cap, and a fluid outlet and a fluid inlet formed on the lower container end cap, the gas inlet is connected to the gas cylinder through a pressure pipeline, the fluid outlet is connected to the sample chamber device through a pressure pipeline, and the pore fluid device also includes a first pressure gauge, which is arranged on the pressure pipeline connected to the fluid outlet of the fluid container.

[0009] Preferably, the pressure vessel comprises a container end cover, a container body, a fixing ring sleeve, a plurality of upper pressure heads, a plurality of lower pressure heads and a plurality of flexible tubes, the upper end of each upper pressure head is inserted into the hole of the container end cover, the lower end of each upper pressure head is inserted into the upper end opening of the corresponding flexible tube, the upper end of each lower pressure head is inserted into the lower end opening of the corresponding flexible tube, and the lower end of each lower pressure head is inserted into the hole on the container body, the upper pressure head is positioned and sealed by the container end cover, the lower pressure head is positioned and sealed by the container body, the top opening of the container body is closed by the container end cover so that the container body and the container end cover form a closed cavity, and the fixing ring sleeve is used to compress the container end cover to achieve the connection and sealing of the container end cover and the container body.

[0010] Preferably, each flexible tube and the upper pressure head and the lower pressure head respectively located at its two ends form a sample chamber, and the pore fluid flowing out of the pore fluid device is respectively transported to each sample chamber through multiple pressure pipeline branches, and each pressure pipeline branch is provided with a stop valve to control the switch of the pore fluid flowing into each sample chamber.

[0011] Preferably, the plurality of sample chambers are accommodated inside the sealed cavity, and the confining pressure device transports liquid into the sealed cavity, so as to apply a certain confining pressure to the outside of the sample chamber through the liquid.

[0012] Preferably, the sample chamber device also includes a heating system, which includes a heating furnace surrounding the pressure vessel, a heating and heat preservation device arranged on the periphery of the heating furnace, a temperature controller for controlling the temperature of the heating furnace, and a thermocouple for measuring the temperature of the heating furnace.

[0013] Preferably, the sample chamber device further comprises a displacement sensor, wherein the displacement sensor is fixed to the upper pressure head of the pressure vessel, and when the upper pressure head of the pressure vessel is displaced, the displacement sensor can measure the displacement amount.

[0014] Preferably, the pressure pump of the confining pressure device is a manual pressure pump, and the confining pressure device further comprises a second pressure gauge, which is arranged on a pressure pipeline connecting the manual pressure pump and the sample chamber device.

[0015] Another aspect of the present invention provides a method for using the above-mentioned penetration healing experiment system, which includes the following steps: Step 1: Provide an penetration healing experiment system; Step 2: Place samples in multiple sample cavities respectively, place the sample cavities in a pressure vessel, and then use the fastening ring sleeve and the container end cover of the pressure vessel to seal the sample cavities inside the pressure vessel; Step 3: Provide confining pressure to the outside of the sample cavity through the pressure pump in the confining pressure device, and measure the value of the provided confining pressure through the second pressure gauge in the confining pressure device; Step 4: Provide pore fluid to the inside of the sample cavity through the pore fluid device, and measure the provided pore pressure through the first pressure gauge in the pore fluid device; Step 5: Control the penetration healing time of the samples in the multiple sample cavities respectively, and after the penetration healing experiment corresponding to the sample in the sample cavity is completed, control the corresponding stop valve to end the penetration healing experiment.

[0016] Preferably, after step 2 and before step 3, the method further includes step 21: closing the stop valves respectively used to control the opening and closing of the pore fluids of the plurality of sample chambers.

[0017] Preferably, after step 3 and before step 4, the following sub-steps are also included: step 31: by closing the stop valve at the bottom of the fluid container for fluid outflow and opening the stop valve at the bottom of the fluid container for fluid inflow, the liquid in the water tank is pumped into the interior of the fluid container; step 32: by opening the stop valve for controlling the switch of the gas cylinder, the gas cylinder is ventilated to the fluid container, and by opening the stop valves at the top of each fluid container for controlling the inflow and outflow of gas, the gas is introduced into the liquid in the fluid container; step 33: by opening one or more of the stop valves at the bottom of the fluid container for fluid outflow and closing one or more of the stop valves for fluid inflow belonging to the same fluid container as the opened stop valve, the porous fluid in one or more of the multiple fluid containers is transported to the sample chamber device; and step 34: by opening the stop valves respectively used to control the switch of the porous fluid of multiple sample chambers, the porous fluid device provides the porous fluid to the interior of the sample chamber.

[0018] Preferably, the following step is further included after step 34: Step 35: When the pore fluid in one or more fluid containers among the multiple fluid containers is exhausted, the stop valve belonging to the fluid container in which the pore fluid is exhausted among the stop valves at the bottom of the fluid container for outflow of fluid is closed, and the stop valve belonging to the fluid container in which the pore fluid is exhausted among the stop valves at the bottom of the fluid container for inflow of fluid is opened, and then the stop valve belonging to the fluid container in which the pore fluid is exhausted among the stop valves at the top of each fluid container for controlling gas inlet is opened, and the stop valve belonging to the fluid container in which the pore fluid is exhausted among the stop valves at the top of each fluid container for controlling gas discharge is closed. The stop valve is opened and the water pump is turned on to replenish the pore fluid to the fluid container in which the pore fluid has been exhausted; step 36: after the fluid container in which the pore fluid has been exhausted is replenished with sufficient pore fluid, the water pump is turned off, the stop valve corresponding to the fluid container in which the pore fluid has been exhausted among the stop valves at the bottom of the fluid container for fluid inflow is closed, the stop valve belonging to the fluid container in which the pore fluid has been exhausted among the stop valves at the top of each fluid container for controlling gas discharge is closed, and the stop valve belonging to the fluid container in which the pore fluid has been exhausted among the stop valves at the bottom of the fluid container for fluid outflow is opened, so that the fluid container after replenishing sufficient pore fluid enters the working state again.

[0019] The beneficial effects of the osmotic healing experimental system and the use method thereof provided by the present invention are as follows:

[0020] First, multiple fluid containers are connected in parallel. When the fluid in a fluid container is about to run out, the corresponding stop valve can be operated to isolate the fluid container from the pore fluid system. After the pore fluid is replenished in the fluid container, the stop valve can be operated to enable the fluid container to re-enter the pore fluid system to work, ensuring that the pore fluid is continuously provided to the sample chamber device and the rock penetration healing experiment is carried out uninterruptedly;

[0021] Second, the osmotic healing experimental system provided by the present invention can realize experiments on multiple samples at the same time, and ensure the consistency of experimental conditions, thereby improving work efficiency, further realizing independent control of the experimental progress of each sample, and increasing the operability of the device;

[0022] Third, the penetration healing experimental system provided by the present invention can apply any temperature condition between room temperature and 90°C to the sample, apply a confining pressure of 0.1MPa to 30MPa, and apply a maximum pore pressure of 2MPa. Therefore, the penetration healing experimental system can realize the free selection of experimental parameters within a large range and meet different requirements for experimental conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic structural diagram of an osmotic healing experimental system according to an embodiment of the present invention is shown.

[0024] Figure 2 A cross-sectional view of a fluid container according to an embodiment of the present invention is shown.

[0025] Figure 3 A top view of an upper end of a fluid container according to an embodiment of the present invention is shown.

[0026] Figure 4 A cross-sectional view of an upper end of a fluid container according to an embodiment of the present invention is shown.

[0027] Figure 5 A top view of a lower end of a fluid container according to an embodiment of the present invention is shown.

[0028] Figure 6 A cross-sectional view of a lower end of a fluid container according to an embodiment of the present invention is shown.

[0029] Figure 7 A cross-sectional view of a sample chamber device according to an embodiment of the present invention is shown.

[0030] Figure 8 A cross-sectional view of a pressure vessel according to an embodiment of the present invention is shown.

[0031] Fig. 9 A top view of a container body of a pressure container according to an embodiment of the present invention is shown.

[0032] Fig.10 The embodiment of the present invention is shown along Fig. 9 A cross-section diagram of the container body is obtained by cutting along the BB line in FIG.

[0033] Fig.11is a table showing the differences in composition and experimental conditions of 9 samples used in a specific experimental process according to an embodiment of the present invention.

[0034] Fig.12 The confining pressure, temperature and pore pressure measurement results during a specific experiment according to an embodiment of the present invention are shown.

[0035] Fig.13 The experimental results of the axial displacement of 9 samples varying with time in a specific experiment according to an embodiment of the present invention are shown.

[0036] Description of reference numerals:

[0037] 10 Pore Fluid Device

[0038] 11Fluid container

[0039] 12 cylinders

[0040] 13 Pressure regulating valve

[0041] 14 Water tank

[0042] 15 Water Pump

[0043] 16 First pressure gauge

[0044] 17 Pore fluid

[0045] 20 sample chamber device

[0046] 21 Pressure Vessel

[0047] 22 Displacement Sensor

[0048] 23 Heating furnace

[0049] 30 Confining pressure device

[0050] 31 Pressure pump

[0051] 32 Second pressure gauge

[0052] 111 Fluid container body

[0053] 112 Container upper end

[0054] 113 Container lower end

[0055] 114 Gas inlet

[0056] 115 Gas outlet

[0057] 116 Fluid inlet

[0058] 117 Fluid outlet

[0059] 211 Container body

[0060] 212 Container end cap

[0061] 213 Fastening ring

[0062] 214 Upper pressure head

[0063] 215 Down pressure head

[0064] 216 Flexible tube. DETAILED DESCRIPTION

[0065] Next, specific embodiments of the present invention are described in detail with reference to the accompanying drawings. The following embodiments do not limit the protection scope of the present invention, and not all combinations of features described in the embodiments are necessary to solve the problem of the present invention.

[0066] Below, refer to Figure 1 The osmotic healing experimental system 100 according to an exemplary embodiment of the present invention is described. Figure 1 The structural schematic diagram of the osmotic healing experimental system 100 according to an embodiment of the present invention is shown, wherein the osmotic healing experimental system 100 includes a pore fluid device 10, a sample chamber device 20 and a confining pressure device 30. The pore fluid device 10 includes a plurality of fluid containers 11 connected in parallel, and each of the plurality of fluid containers 11 contains a pore fluid 17. The sample chamber device 20 includes a pressure container 21 for containing a sample. The confining pressure device 30 includes a pressure pump 31. The fluid container 11 in the pore fluid device 10 is connected to the pressure container 21 in the sample chamber device 20 through a pipeline, and the confining pressure device 30 applies pressure to the inside of the pressure container 21 through the pressure pump 31. The pore fluid 17 flows from the fluid container 11 into the pressure container 21 in the sample chamber device 20 through the pipeline, and the pressure pump 31 provides a liquid with a certain pressure to the pressure container 21. The various components of the above-mentioned osmotic healing experimental system 100 are introduced one by one below.

[0067] In addition to the fluid container 11, the pore fluid device 10 also includes a gas cylinder 12, a pressure regulating valve 13, a water tank 14, a water pump 15, a first pressure gauge 16 and a plurality of stop valves. The gas cylinder 12 stores gas for being transported to the fluid container 11 through a pressure pipeline. A pressure regulating valve 13 for adjusting the gas pressure output by the gas cylinder 12 and a stop valve C4 for controlling the switch of the gas cylinder 12 are arranged on the pressure pipeline connected to the gas cylinder 12. Preferably, in this embodiment, the gas in the gas cylinder 12 is, for example, carbon dioxide gas. The water tank 14 and the water pump 15 are connected through a pressure pipeline, and the water pumped out by the water pump 15 is respectively transported to the fluid inlet 116 of each fluid container 11 through the pressure pipeline. The water pump 15 can also contain mineralized fluids of different components. In this embodiment, water and carbon dioxide are mixed into a saturated solution of calcium carbonate inside the fluid container 11 as a pore fluid 17 (the pore fluid 17 is, for example, a liquid flowing in the pores of a rock). The pore fluid 17 in the multiple fluid containers 11 is output through the fluid outlet 117 at the bottom of the fluid container 11 and the pressure pipeline, and the output pore fluid 17 is gathered into a total output pipeline, and is uniformly transported to the sample chamber device 20 by the total output pipeline. The first pressure gauge 16 is used to measure the pressure of the pore fluid 17 in the total output pipeline, hereinafter referred to as the pore pressure. The range of the pore pressure can be, for example, 0.1MPa to 2MPa. The pore pressure is numerically equal to the pressure of the gas in the gas cylinder, so the pore pressure can be adjusted by the pressure regulating valve 13.

[0068] Figure 2 FIG. 1 shows a cross-sectional view of a fluid container 11 according to an embodiment of the present invention. Figure 2 The fluid container 11 includes a cylindrical fluid container body 111, an upper container head 112 for sealing the upper end opening of the fluid container body 111, a lower container head 113 for sealing the lower end opening of the fluid container body 111, a gas inlet 114 and a gas outlet 115 formed on the upper container head 112, and a fluid inlet 116 and a fluid outlet 117 formed on the lower container head 113. The gas inflow and outflow at the upper part of each fluid container 11 are controlled by the stop valve, and the fluid inflow and outflow at the lower part of each fluid container 11 are controlled. Please refer to Figure 1 For example, stop valves A1 and B1 control the inflow and outflow of fluid in the first fluid container 11, stop valves A2 and B2 control the inflow and outflow of fluid in the second fluid container 11, stop valves A3 and B3 control the inflow and outflow of fluid in the third fluid container 11, stop valves C1 and D1 control the inflow and outflow of gas in the first fluid container 11, stop valves C2 and D2 control the inflow and outflow of gas in the second fluid container, and stop valves C3 and D3 control the inflow and outflow of gas in the third fluid container.

[0069] Preferably, the number of the multiple fluid containers 11 can be three. The three fluid containers 11 are connected in parallel, that is, the three fluid containers 11 can be switched on and off individually. During use, when the fluid in a fluid container 11 is about to run out, the shut-off valve corresponding to the fluid container 11 is operated to disconnect the fluid container 11, and the fluid container 11 is isolated from the pore fluid device 10, and no pore fluid 17 is provided to the sample chamber device 20. After the pore fluid 17 is replenished to the fluid container 11 that has run out of pore fluid 17, the corresponding shut-off valve is opened, and the fluid container 11 can work again. In this way, by switching multiple fluid containers 11, it is possible to ensure that the infiltration healing experiment in the sample chamber device 20 is carried out uninterruptedly to meet the requirements of a long-term infiltration healing experiment.

[0070] Figure 3 A top view of a container upper end 112 of a fluid container 11 according to an embodiment of the present invention is shown. Figure 4 FIG. 1 is a cross-sectional view of an upper end 112 of a fluid container 11 according to an embodiment of the present invention. Figure 3 and Figure 4 The upper end 112 of the container is a round cap-shaped end with a T-shaped cross section, and a through hole is formed inside the upper end 112 of the container to allow gas to enter and exit. Figure 5 A top view of a container lower end 113 of a fluid container 11 according to an embodiment of the present invention is shown. Figure 6 FIG. 1 is a cross-sectional view of a lower end 113 of a fluid container 11 according to an embodiment of the present invention. Figure 5 and Figure 6 The lower end 113 of the container is a round cap-shaped end with a T-shaped cross section, and a through hole is formed inside the lower end 113 of the container to allow fluid to enter and exit. The gas inlet 114 of each fluid container 11 is connected to the gas cylinder 12 through a pressure pipeline, so that the gas in the gas cylinder 12 can be transported to the inside of the fluid container 11. The gas outlet 115 of each fluid container 11 is connected to the outside through a pressure pipeline. A shut-off valve, such as a shut-off valve D1, a shut-off valve D2 and a shut-off valve D3, is arranged on the pressure pipeline connected to the gas outlet 115 of the fluid container 11. When the fluid container 11 is in working state, the shut-off valve is closed. When the pore fluid 17 in the fluid container 11 is exhausted and the pore fluid 17 is replenished to the fluid container 11, the shut-off valves D1, D2 and D3 are opened.

[0071] The sample chamber device 20 includes a pressure container 21 , a heating system and a displacement sensor 22 . Figure 7The schematic diagram of the structure of the sample chamber device 20 according to the embodiment of the present invention is shown. The pressure vessel 21 is used to contain the sample and provide an experimental environment for the sample. The heating system is used to provide the required experimental temperature for the pressure vessel 21. The heating system includes a heating furnace 23, a heating and heat preservation device arranged outside the heating furnace 23, a temperature controller for controlling the temperature of the heating furnace 23, and a thermocouple for measuring the temperature of the heating furnace 23. Figure 7 , the heating furnace 23 is cylindrical, and the pressure vessel 21 is arranged inside the heating furnace 23. Through the heating system, the sample of the pressure vessel 21 is subjected to the penetration healing experiment between room temperature and 90°C. The displacement sensor 22 is arranged on the top of the pressure vessel 21. Specifically, the displacement sensor 22 is fixed to the upper pressure head 214 of the pressure vessel 21 (the upper pressure head 214 is a component of the pressure vessel 21, described below), and when the upper pressure head 214 of the pressure vessel 21 is displaced, the displacement sensor 22 can measure the displacement. The displacement reflects the trend of the compaction creep effect of the sample.

[0072] In an embodiment of the present invention, the pressure vessel 21 includes a vessel body 211, a vessel end cover 212, a fixing ring 213, a plurality of upper pressure heads 214, a plurality of lower pressure heads 215 and a plurality of flexible tubes 216. Preferably, the flexible tubes 216 are, for example, rubber tubes or silicone tubes. In an embodiment of the present invention, Figure 8 FIG. 2 shows a cross-sectional view of a pressure vessel 21 according to an embodiment of the present invention. Figure 8 , the upper end of the upper pressure head 214 is inserted into the hole on the container end cover 212, the lower end of the upper pressure head 214 is inserted into the upper end opening of the flexible tube 216, the upper end of the lower pressure head 215 is inserted into the lower end opening of the flexible tube 216, and the lower end of the lower pressure head 215 is inserted into the hole of the container body 211. Each flexible tube 216 and the upper pressure head 214 and the lower pressure head 215 respectively located at both ends thereof constitute a sample cavity. Preferably, in this embodiment, there are 9 sample cavities in total. In addition, a fluid inlet hole is formed in the middle of each upper pressure head 214 so that the pore fluid 17 flowing out of the pore fluid device 10 can flow into the sample cavity through the fluid inlet hole. A fluid outlet hole is also formed in the middle of each lower pressure head 215, and the permeate precipitated from the sample in the sample cavity during the infiltration healing experiment can flow out through the fluid outlet hole. Placing a balance or a flowmeter below the lower pressure head 215 can measure the mass of the permeate precipitated from the sample. The pore fluid 17 flowing out of the pore fluid device 10 is divided into a plurality of pressure pipeline branches and respectively delivered to each sample chamber.

[0073] In the present invention, each pressure line branch is provided with a stop valve to control the opening and closing of the pore fluid 17 flowing into each sample chamber, for example, see Figure 1, the stop valves F1, F2, F3, F4, F5, F6, F7, F8 and F9 are respectively used to control the opening and closing of the pore fluid 17 in the nine sample chambers. The container end cap 212 is used for positioning and sealing the upper pressure head 214, and the container body 211 is used for positioning and sealing the lower pressure head 215. The fastening ring 213 is used to press the container end cap 212 to achieve the connection and sealing of the container end cap 212 and the container body 211. Since the container end cap 212 is only used for positioning and sealing the upper pressure head 214, when the size of the sample in the sample chamber changes, the upper pressure head 214 will move downward, and the displacement sensor fixed to the upper pressure head 214 can measure the displacement of the upper pressure head 214.

[0074] Fig. 9 A top view of a container body 211 is shown according to an embodiment of the present invention. Fig.10 The embodiment of the present invention is shown along Fig. 9 The cross-section of the container body 211 is obtained by cutting along the BB line in FIG. Fig. 9 and Fig.10 It can be seen that the container body 211 is a groove structure, and a plurality of holes are formed at the bottom thereof so that the lower pressure head 215 can pass through. A plurality of holes are also formed in the middle of the container end cover 212 so that the upper pressure head 214 can pass through the holes. The top opening of the container body 211 is closed by the container end cover 212 so that the container body 211 and the container end cover 212 form a closed cavity. A plurality of sample cavities are accommodated inside the closed cavity. The confining pressure device 30 transports liquid into the closed cavity, so that the liquid applies a certain confining pressure to the outside of the sample cavity.

[0075] In the present invention, the confining pressure device 30 includes a pressure pump 31, a second pressure gauge 32 and a pressure pipeline. Preferably, the pressure pump 31 is a manual pressure pump. The liquid pumped out by the manual pressure pump is transported to the sample chamber device 20 through the pressure pipeline, specifically, to the closed cavity of the pressure container 21. Preferably, the liquid is water. The second pressure gauge 32 is arranged on the pressure pipeline to measure the pressure of the liquid transported to the sample chamber device 20, that is, the confining pressure. The range of the confining pressure is 0.1MPa to 30MPa, preferably, the range of the confining pressure is 0.1MPa to 25MPa.

[0076] See also Fig.11 , Fig.11 The table shows the composition and experimental conditions of the nine experimental samples of the preferred embodiment of the present invention. The specific experimental process is: the nine samples are all calcite, but the particle diameter, sample diameter and pore fluid flow conditions are different. For details, please refer to Fig.11 The specific experimental process is: Fig.11The 9 samples in the table are placed in the flexible tube 216 respectively, the water tank 14 contains pure water, the gas cylinder 12 outputs carbon dioxide gas, and the output pressure of the carbon dioxide gas is 1MPa, so that the two are mixed in the fluid container 11 to form a saturated calcium carbonate solution, and the pore pressure of the saturated calcium carbonate solution is 1MPa. The manual pressure pump provides 5MPa of water to the closed cavity of the pressure vessel 21, that is, the confining pressure in the closed cavity is 5MPa. During the experiment, 8 samples were subjected to the penetration healing experiment under the same conditions of pore pressure of 1MPa and confining pressure of 5MPa, and 1 sample was subjected to the penetration healing experiment under the condition of no pore pressure and confining pressure of 5MPa. The penetration healing time of the sample can be controlled by closing the stop valves F1 to F9 of the switch pore fluid 17 corresponding to the relevant sample. In this embodiment, the experimental time of the 9 experimental samples is 150 hours. It can be understood that the experimental time can be adjusted according to actual needs. Afterwards, a comparative analysis of parameters such as the changes in sample structure before and after, the outflow of sample permeate, and the trend of sample compaction creep are conducted on samples with different penetration healing times. This allows comparison of changes in sample penetration healing rates under different external conditions. By conducting experiments on different samples, the healing characteristics of different types of fault rocks can be compared.

[0077] See also Fig.12 , Fig.12 The results of the confining pressure, temperature and pore pressure measurements during the specific experiment according to the embodiment of the present invention are shown. Fig.12 It can be seen that the system can achieve high-precision pressure and temperature control, and can meet the requirements of stable experimental conditions required by the experiment.

[0078] See also Fig.13 , Fig.13 The experimental results of the axial displacement of 9 samples changing with time in a specific experiment according to an embodiment of the present invention are shown. Fig.13 It can be seen that under constant pressure loading conditions, the axial displacements of different samples gradually increase, indicating that the samples undergo compaction creep. The axial displacement is the displacement measured by a displacement sensor fixed to the upper pressure head 214 of the pressure vessel 21 .

[0079] Next, the method of using the above-mentioned osmotic healing experimental system 100 is described in detail.

[0080] The method of using the above-mentioned osmotic healing experimental system 100 in the present invention includes the following steps:

[0081] Step 1: Provide an infiltration healing experiment system; Step 2: Place samples in multiple sample cavities respectively, place the sample cavities in a pressure vessel 21, and then use the fastening ring sleeve 213 and the container end cover 212 of the pressure vessel 21 to seal the sample cavity inside the pressure vessel 21; Step 3: Provide confining pressure to the outside of the sample cavity through the pressure pump 31 in the confining pressure device 30, and measure the value of the provided confining pressure through the second pressure gauge 32 in the confining pressure device 30; Step 4: Provide pore fluid 17 to the inside of the sample cavity through the pore fluid device 10, and measure the provided pore pressure through the first pressure gauge 16 in the pore fluid device 10; Step 5: Control the infiltration healing time of the samples in the multiple sample cavities respectively, and after the infiltration healing experiment corresponding to the sample in the sample cavity is completed, control the corresponding stop valve to end the infiltration healing experiment.

[0082] Preferably, after step 2 and before step 3, the method further includes step 21: closing the stop valves F1 to F9 respectively used to control the on / off of the pore fluids 17 of the plurality of sample chambers.

[0083] Preferably, after step 3 and before step 4, the following sub-steps are further included: step 31: by closing the stop valves B1 to B3 at the bottom of the fluid container 11 for the fluid to flow out and opening the stop valves A1 to A3 at the bottom of the fluid container 11 for the fluid to flow in, the liquid in the water tank 14 is pumped into the fluid container 11; step 32: by opening the stop valve C4 for controlling the switch of the gas cylinder 12, the gas cylinder 12 is ventilated to the fluid container 11, and by opening the stop valves C1 to C3 and D1 to D3 at the top of each fluid container 11 for controlling the gas inlet and outlet, the liquid in the fluid container 11 is ventilated. Introduce gas; step 33: open one or more of the stop valves B1 to B3 at the bottom of the fluid container 11 for outflow of fluid and close one or more of the stop valves A1 to A3 for inflow of fluid that belong to the same fluid container 11 as the opened stop valves B1 to B3, so that the porous fluid 17 in one or more fluid containers 11 among the multiple fluid containers 11 is transported to the sample chamber device 20; and step 34: open the stop valves F1 to F9 respectively used to control the switching of the porous fluid 17 of multiple sample chambers, so that the porous fluid device 10 provides the porous fluid 17 to the interior of the sample chamber.

[0084] Preferably, the following step is further included after step 34: Step 35: When the pore fluid 17 in one or more fluid containers among the plurality of fluid containers 11 is exhausted, the shut-off valves B1 to B3 at the bottom of the fluid container 11 for outflow of fluid, which belong to the fluid container 11 where the pore fluid 17 is exhausted, are closed, and the shut-off valves A1 to A3 at the bottom of the fluid container 11 for inflow of fluid, which belong to the fluid container 11 where the pore fluid 17 is exhausted, are opened, and then the shut-off valves C1 to C3 at the top of each fluid container 11 for controlling gas inlet, which belong to the fluid container 11 where the pore fluid 17 is exhausted, are opened, and the shut-off valves D1 to D3 at the top of each fluid container 11 for controlling gas discharge, which belong to the fluid container 11 where the pore fluid 17 is exhausted, are closed. 1, and start the water pump to replenish the pore fluid to the fluid container 11 in which the pore fluid 17 is exhausted; step 36: after the fluid container 11 in which the pore fluid 17 is exhausted is replenished with sufficient pore fluid, turn off the water pump, close the stop valve corresponding to the fluid container 11 in which the pore fluid 17 is exhausted among the stop valves A1 to A3 at the bottom of the fluid container 11 for fluid inflow, close the stop valve belonging to the fluid container 11 in which the pore fluid 17 is exhausted among the stop valves D1 to D3 at the top of each fluid container 11 for controlling gas discharge, and open the stop valve belonging to the fluid container 11 in which the pore fluid 17 is exhausted among the stop valves B1 to B3 at the bottom of the fluid container 11 for fluid outflow, so that the fluid container 11 after sufficient pore fluid is replenished enters the working state again.

[0085] The beneficial effects of the osmotic healing experimental system 100 and the use method thereof provided by the present invention are:

[0086] First, multiple fluid containers 11 are connected in parallel. When the fluid in a fluid container 11 is about to run out, the corresponding stop valve can be operated to isolate the fluid container 11 from the pore fluid 17 system. After the pore fluid 17 is replenished in the fluid container 11, the stop valve can be operated to enable the fluid container 11 to re-enter the pore fluid 17 system to work, thereby ensuring that the pore fluid 17 is continuously provided to the sample chamber device 20 and the rock penetration healing experiment is carried out uninterruptedly;

[0087] Second, the osmotic healing experimental system 100 provided by the present invention can realize experiments on multiple samples at the same time, and ensure the consistency of experimental conditions, thereby improving work efficiency, further realizing independent control of the experimental progress of each sample, and increasing the operability of the device; and

[0088] Third, the penetration healing experimental system 100 provided by the present invention can apply any temperature condition between room temperature and 90°C to the sample, apply a confining pressure of 0.1MPa to 30MPa, and apply a maximum pore pressure of 2MPa. Therefore, the penetration healing experimental system 100 can realize the free selection of experimental parameters within a large range and meet different requirements for experimental conditions.

[0089] While the present invention has been described with reference to the embodiments, it is to be understood that the invention is not limited to the disclosed embodiments.The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. An osmotic healing experimental system, characterized in that: The osmotic healing experimental system comprises: a pore fluid device (10), a sample chamber device (20) and a confining pressure device (30), wherein the pore fluid device (10) comprises a plurality of fluid containers (11) connected in parallel, each of the plurality of fluid containers (11) containing a pore fluid (17) therein, the sample chamber device (20) comprising a pressure container (21) for containing a sample, and the confining pressure device (30) comprising a pressure pump (31), The fluid container (11) in the pore fluid device (10) is connected to the pressure container (21) in the sample chamber device (20) through a pipeline, and the confining pressure device (30) applies pressure to the interior of the pressure container (21) through the pressure pump (31). The pore fluid (17) flows from the fluid container (11) into the pressure container (21) in the sample chamber device (20) through the pipeline, and the pressure pump (31) provides pressurized liquid to the pressure container (21). The pore fluid device (10) further comprises a gas cylinder (12), a water pump (15) and a plurality of stop valves, wherein the plurality of stop valves are arranged on the pressure pipeline to control the switching of the water pump (15), the gas cylinder (12) and the pressure container (21). The pressure vessel (21) comprises a vessel body (211), a plurality of upper pressure heads (214), a plurality of lower pressure heads (215) and a plurality of flexible tubes (216); each flexible tube (216) and the upper pressure head (214) and the lower pressure head (215) respectively located at two ends thereof form a sample chamber; the vessel body (211) is a groove structure, and a plurality of holes are formed at the bottom thereof to allow the lower pressure head (215) to pass through.

2. The osmotic healing experimental system according to claim 1, characterized in that: The pore fluid device (10) further comprises a pressure regulating valve (13) and a water tank (14); the water tank (14) and the water pump (15) are connected via a pressure pipeline; the liquid pumped out by the water pump (15) is respectively transported to the inside of each of the fluid containers (11) via the pressure pipeline; the gas cylinder (12) and the pressure regulating valve (13) are connected via a pressure pipeline; the gas in the gas cylinder (12) is transported to the inside of each of the fluid containers (11) via the pressure pipeline.

3. The osmotic healing experimental system according to claim 2, characterized in that: The gas stored in the gas cylinder (12) is carbon dioxide gas, and the gas stored in the water pump (15) is water or mineralized fluid.

4. The osmotic healing experimental system according to claim 2, characterized in that: Each fluid container (11) among the plurality of fluid containers (11) comprises a cylindrical fluid container body (111), an upper container head (112) for sealing the upper opening of the fluid container body (111), a lower container head (113) for sealing the lower opening of the fluid container body (111), a gas outlet (115) and a gas inlet (114) formed on the upper container head (112), and a fluid outlet (117) and a fluid inlet (116) formed on the lower container head (113), wherein the gas inlet (114) is connected to the gas cylinder (12) via a pressure pipeline, and the fluid outlet (117) is connected to the sample chamber device (20) via a pressure pipeline. The pore fluid device (10) further comprises a first pressure gauge (16), which is arranged on a pressure pipeline connected to the fluid outlet (117) of the fluid container (11).

5. The osmotic healing experimental system according to claim 3, characterized in that: The pressure vessel (21) further comprises a vessel end cover (212) and a fixing ring (213), the upper end of each upper pressure head (214) is inserted into the hole of the vessel end cover (212), the lower end of each upper pressure head (214) is inserted into the upper end opening of the corresponding flexible tube (216), the upper end of each lower pressure head (215) is inserted into the lower end opening of the corresponding flexible tube (216), the lower end of each lower pressure head (215) is inserted into the hole on the vessel body (211), and the upper pressure head (214) is inserted into the hole of the vessel end cover (212). ) is positioned and sealed by the container end cover (212), the pressure head (215) is positioned and sealed by the container body (211), the top opening of the container body (211) is closed by the container end cover (212) so that the container body (211) and the container end cover (212) form a closed cavity, and the fastening ring sleeve (213) is used to press the container end cover (212) to achieve the connection and sealing of the container end cover (212) and the container body (211).

6. The osmotic healing experimental system according to claim 5, characterized in that: The pore fluid (17) flowing out of the pore fluid device (10) is transported to each sample cavity through a plurality of pressure pipeline branches, and each pressure pipeline branch is provided with a stop valve for controlling the opening and closing of the pore fluid (17) flowing into each sample cavity.

7. The osmotic healing experimental system according to claim 6, characterized in that: A plurality of sample chambers are accommodated inside the sealed cavity, and the confining pressure device (30) transports liquid into the sealed cavity, thereby applying confining pressure to the outside of the sample chamber through the liquid.

8. The osmotic healing experimental system according to claim 1, characterized in that: The sample chamber device (20) also includes a heating system, which includes a heating furnace surrounding the pressure container (21), a heating and heat preservation device arranged outside the heating furnace, a temperature controller for controlling the temperature of the heating furnace, and a thermocouple for measuring the temperature of the heating furnace.

9. The osmotic healing experimental system according to claim 5, characterized in that: The sample chamber device (20) further comprises a displacement sensor, which is fixed to the upper pressure head (214) of the pressure container (21). When the upper pressure head (214) of the pressure container (21) is displaced, the displacement sensor can measure the displacement amount.

10. The osmotic healing experimental system according to claim 1, characterized in that: The pressure pump (31) of the confining pressure device (30) is a manual pressure pump. The confining pressure device (30) further comprises a second pressure gauge (32). The second pressure gauge (32) is arranged on a pressure pipeline connecting the manual pressure pump and the sample chamber device (20).

11. A method for using the osmotic healing experimental system according to any one of claims 1 to 10, characterized in that: The method comprises the following steps: Step 1: Provide an osmotic healing experimental system; Step 2: placing samples in the plurality of sample cavities respectively, placing the sample cavities in the pressure container (21), and then sealing the sample cavities in the pressure container (21) using the fixing ring sleeve (213) and the container end cover (212) of the pressure container (21); Step 3: providing a confining pressure to the outside of the sample chamber through a pressure pump (31) in the confining pressure device (30), and measuring the value of the provided confining pressure through a second pressure gauge (32) in the confining pressure device (30); Step 4: providing a pore fluid (17) to the interior of the sample chamber through the pore fluid device (10), and measuring the provided pore pressure through the first pressure gauge (16) in the pore fluid device (10); Step 5: Control the penetration healing time of samples in multiple sample chambers respectively, and after the penetration healing experiment corresponding to the samples in the sample chamber is completed, control the corresponding stop valve to end the penetration healing experiment.

12. The method for using the osmotic healing experimental system according to claim 11, characterized in that: After step 2 and before step 3, the method further includes step 21: closing the stop valves (F1 to F9) respectively used to control the opening and closing of the pore fluids (17) of the plurality of sample chambers.

13. The method for using the osmotic healing experimental system according to claim 11, characterized in that: After step 3 and before step 4, the following sub-steps are also included: Step 31: By closing the stop valve (B1 to B3) at the bottom of the fluid container (11) for the fluid to flow out and opening the stop valve (A1 to A3) at the bottom of the fluid container (11) for the fluid to flow in, the liquid in the water tank (14) is pumped into the interior of the fluid container (11); Step 32: Open the stop valve (C4) for controlling the opening and closing of the gas cylinder (12) to allow the gas cylinder (12) to ventilate the fluid container (11); and open the stop valves (C1 to C3 and D1 to D3) for controlling the inflow and outflow of gas at the top of each fluid container (11) to allow gas to enter the liquid in the fluid container (11); Step 33: by opening one or more of the stop valves (B1 to B3) for outflow of fluid at the bottom of the fluid container (11) and closing one or more of the stop valves (A1 to A3) for inflow of fluid belonging to the same fluid container (11) as the opened stop valves (B1 to B3), the pore fluid (17) in one or more fluid containers (11) among the plurality of fluid containers (11) is transported to the sample chamber device (20); and Step 34: Open the stop valves (F1 to F9) respectively used to control the on / off of the pore fluids (17) of the multiple sample chambers, so that the pore fluid device (10) provides the pore fluid (17) to the interior of the sample chamber.

14. The method for using the osmotic healing experimental system according to claim 13, characterized in that: After step 34, the following steps are also included: Step 35: When the pore fluid (17) in one or more fluid containers among the multiple fluid containers (11) is exhausted, the shut-off valves (B1 to B3) at the bottom of the fluid container (11) for outflow of fluid belonging to the fluid container (11) in which the pore fluid (17) is exhausted are closed, and the shut-off valves (A1 to A3) at the bottom of the fluid container (11) for inflow of fluid belonging to the fluid container (11) in which the pore fluid (17) is exhausted are opened, and then the shut-off valves (C1 to C3) at the top of each fluid container (11) for controlling gas entry and the shut-off valves (D1 to D3) at the top of each fluid container (11) for controlling gas discharge and the shut-off valves (D1 to D3) at the top of each fluid container (11) for controlling gas discharge and the shut-off valves (11) belonging to the fluid container (11) in which the pore fluid (17) is exhausted are opened, and the water pump is started to replenish the pore fluid to the fluid container (11) in which the pore fluid (17) is exhausted; Step 36: After the fluid container (11) in which the pore fluid (17) is exhausted is replenished with pore fluid that meets a preset threshold, the water pump is turned off, and the shut-off valve corresponding to the fluid container (11) in which the pore fluid (17) is exhausted among the shut-off valves (A1 to A3) at the bottom of the fluid container (11) for fluid inflow is closed, and the shut-off valve belonging to the fluid container (11) in which the pore fluid (17) is exhausted among the shut-off valves (D1 to D3) at the top of each fluid container (11) for controlling gas discharge is closed, and the shut-off valve belonging to the fluid container (11) in which the pore fluid (17) is exhausted among the shut-off valves (B1 to B3) at the bottom of the fluid container (11) for fluid outflow is opened, so that the fluid container (11) after being replenished with pore fluid that meets the preset threshold re-enters the working state.

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