CN113622906B - Testing device and testing method for simulating mechanical properties of ocean energy soil-well interface in hydrate exploitation process - Google Patents
Testing device and testing method for simulating mechanical properties of ocean energy soil-well interface in hydrate exploitation process Download PDFInfo
- Publication number
- CN113622906B CN113622906B CN202110924314.0A CN202110924314A CN113622906B CN 113622906 B CN113622906 B CN 113622906B CN 202110924314 A CN202110924314 A CN 202110924314A CN 113622906 B CN113622906 B CN 113622906B
- Authority
- CN
- China
- Prior art keywords
- soil
- hydrate
- pressure
- well interface
- sample
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 63
- 238000012360 testing method Methods 0.000 title claims abstract description 59
- 230000008569 process Effects 0.000 title claims abstract description 46
- 239000002689 soil Substances 0.000 claims abstract description 51
- 239000007789 gas Substances 0.000 claims abstract description 46
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 29
- 239000007788 liquid Substances 0.000 claims abstract description 28
- 238000000354 decomposition reaction Methods 0.000 claims abstract description 25
- NMJORVOYSJLJGU-UHFFFAOYSA-N methane clathrate Chemical compound C.C.C.C.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O NMJORVOYSJLJGU-UHFFFAOYSA-N 0.000 claims abstract description 22
- 238000011068 loading method Methods 0.000 claims abstract description 16
- 238000011084 recovery Methods 0.000 claims abstract description 15
- 238000010008 shearing Methods 0.000 claims abstract description 13
- 238000000926 separation method Methods 0.000 claims abstract description 10
- 238000005065 mining Methods 0.000 claims abstract description 9
- 230000005540 biological transmission Effects 0.000 claims abstract description 5
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 29
- 230000001105 regulatory effect Effects 0.000 claims description 11
- 229910000831 Steel Inorganic materials 0.000 claims description 10
- 239000010959 steel Substances 0.000 claims description 10
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 7
- 239000000741 silica gel Substances 0.000 claims description 7
- 229910002027 silica gel Inorganic materials 0.000 claims description 7
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 230000001276 controlling effect Effects 0.000 claims description 4
- 238000006243 chemical reaction Methods 0.000 claims description 3
- 238000001035 drying Methods 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- 239000008367 deionised water Substances 0.000 claims description 2
- 229910021641 deionized water Inorganic materials 0.000 claims description 2
- 239000003292 glue Substances 0.000 claims description 2
- 238000002156 mixing Methods 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 239000011148 porous material Substances 0.000 claims description 2
- 238000007789 sealing Methods 0.000 claims description 2
- 230000002194 synthesizing effect Effects 0.000 claims description 2
- 238000001514 detection method Methods 0.000 claims 1
- 230000015572 biosynthetic process Effects 0.000 abstract description 7
- 238000003786 synthesis reaction Methods 0.000 abstract description 7
- 239000003345 natural gas Substances 0.000 description 7
- 238000011160 research Methods 0.000 description 6
- 239000013049 sediment Substances 0.000 description 5
- 239000007921 spray Substances 0.000 description 5
- 230000009471 action Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000006073 displacement reaction Methods 0.000 description 3
- 230000003313 weakening effect Effects 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000003595 mist Substances 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- -1 Natural gas hydrates Chemical class 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000001186 cumulative effect Effects 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 150000004677 hydrates Chemical class 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000013535 sea water Substances 0.000 description 1
- 125000006850 spacer group Chemical group 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
- E21B49/001—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells specially adapted for underwater installations
Abstract
The invention belongs to the field of ocean energy soil exploitation mechanical testing, and particularly relates to a testing device and a testing method for simulating the mechanical characteristics of an ocean energy soil-well interface in a hydrate exploitation process. The testing device comprises a triaxial pressure chamber, a stress loading system, an air supply pressurizing system, a water bath tank, a soil-well interface sample, a back pressure valve, a gas-liquid separation and recovery system and a data acquisition system; the stress loading system is connected with the triaxial pressure chamber to realize loading in different stress modes; the gas supply pressurizing system is connected with the triaxial pressure chamber, and is used for providing a gas source and controlling the application of gas pressure to generate hydrate; the water bath tank system seamlessly surrounds the triaxial pressure chamber and controls the indoor temperature; splicing the mining well interface with a soil body sample, installing the mining well interface into a triaxial pressure chamber, and simulating the mechanical properties of the soil-well interface in the mining process; the data transmission acquisition processor is respectively connected with the triaxial pressure chamber, the high-pressure pump, the confining pressure loader, the axial pressure loader, the water bath tank and the back pressure valve, and periodically acquires test data and stores and processes the test data. The invention realizes the synthesis of the soil containing the natural gas hydrate, controls the time of high-temperature low-pressure decomposition of the hydrate, and can accurately test the shearing characteristic between the ocean energy soil and the well interface in the process of exploiting the hydrate.
Description
Technical Field
The invention belongs to the field of ocean energy soil exploitation mechanical testing, and particularly relates to a testing device and a testing method for simulating the mechanical properties of an ocean energy soil-well interface in a hydrate exploitation process.
Background
The natural gas hydrate is a novel clean energy source, and is estimated by the national resource department, so that the natural gas hydrate has very rich hydrate resources in the east sea, the south sea and the adjacent sea areas of China. Natural gas hydrates are usually formed in loose sediments of deep water shallow coverage, have the characteristics of poor cementing and low strength, and can generate the phenomenon of weakening of a soil-well interface in the deep sea exploitation process: the natural gas hydrate coating softens the soil-structure interface under the cyclic load action of the anti-pulling structure; liquefying the soil-well interface under the action of deep seawater power; the multi-process coupling (deformation process, chemical process, seepage process, heat conduction, etc.) in the exploitation process can cause the natural gas hydrate at the soil-well interface to change phase. Weakening of the soil-well structure interface can cause instability of the foundation of the exploitation platform, and seriously damages the exploitation safety of natural gas hydrate. However, the current research on natural gas hydrate is only focused on productivity evaluation and mechanical properties of sediment, and the interaction between soil and well interfaces in the process of hydrate exploitation is ignored. Therefore, the research on the mechanical properties of the marine energy soil-well interface containing the natural gas hydrate in the hydrate exploitation process is of great significance to the hydrate exploitation.
The mechanical property of ocean energy soil is one of the important points of the current research, and few simulation experiments are carried out on the soil-well structure interface containing natural gas hydrate. Zhou Yuan et al in the "development and application of gas hydrate spray synthesis and direct shear test System", developed a gas hydrate spray synthesis and direct shear test System, the system includes a hydrate spray synthesis subsystem and a low-temperature high-pressure direct shear subsystem containing hydrate soil, the hydrate spray synthesis system is composed of a gas supply module, a water supply module, a temperature control module and a reaction kettle module, the hydrate spray synthesis device is in a high-pressure low-temperature environment, and the hydrate is rapidly synthesized by spraying water mist and reacting water mist with gas, so that the power-sustaining type gas hydrate can be rapidly and efficiently prepared by the method. The system is composed of an air supply module, a stress loading module, a temperature control module and a data acquisition module, and can realize direct shear test of cemented and filled hydrates by applying axial pressure by a constant-speed constant-pressure pump. Compared with the triaxial shear test, the direct shear test is more convenient and time-saving, and can quickly obtain the mechanical parameters of the sediment. However, the system cannot simulate different working conditions of hydrate exploitation and cannot simulate the mechanical characteristics between hydrate sediment and an exploitation well structure interface in the hydrate exploitation process.
Based on reference to related research data of natural gas hydrate experiments at home and abroad, the existing hydrate test device is considered to have certain limitation. At present, most of domestic and foreign mechanical property test researches of the natural gas-containing hydrate are developed through triaxial test based on the synthesis of the indoor natural gas hydrate, and simulation experiments between soil-well structure interfaces of the natural gas-containing hydrate are directly realized through simulating various properties of the soil body of the natural gas-containing hydrate under different geological conditions (confining pressure, air pressure, temperature and the like) and in different exploitation modes. At present, the related research on the mechanical properties of the soil-structural surface is carried out by a direct shear apparatus, and the exploitation process of the natural gas hydrate cannot be simulated. The invention improves on the basis of the existing hydrate test equipment at present, and combines the traditional direct shear test to invent a device and a method for testing the mechanical properties of the marine energy soil-well interface in the process of simulating hydrate exploitation. The device can be used for preparing the natural gas-containing hydrate soil in a high-pressure low-temperature environment and developing a conventional mechanical test of the natural gas-containing hydrate soil, can control the decomposition time of the hydrate, simulate the influence of the hydrate exploitation process on the mechanical property of hydrate sediment, simulate the shearing process of a soil-well interface in the hydrate exploitation process, and provide good test technical support for researching the weakening behavior of a soil-structural surface in the hydrate exploitation process.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides a testing device and a testing method for simulating the mechanical properties of an ocean energy soil-well interface in the process of hydrate exploitation. The device can test the shear mechanical characteristics of the marine energy soil-well interface in the hydrate exploitation process, display the shear mechanical characteristics by using a data acquisition system, and has simple operation and reliable results.
In order to achieve the above object, the present invention adopts the following solution:
a test device for simulating mechanical properties of an ocean energy soil-well interface in a hydrate exploitation process, comprising: the device comprises a triaxial pressure chamber, a shaft pressure loader, a confining pressure loader, an air supply pressure regulating system, a water bath tank, a back pressure valve, a gas-liquid separation and recovery device and a data transmission acquisition processor. The device can provide a maximum axial load of 1500kN, a maximum confining pressure of 60MPa, an application range of air pressure of 0-20 MPa and an adjustment range of temperature of-30-99.9 ℃. Wherein: the gas supply pressure regulating system, the confining pressure loader and the shaft pressure loader are respectively connected with the triaxial pressure chamber to realize gas pressure application and loading of different stress modes and different stress paths; the backpressure valve can control hydrate decomposition; the water bath tank seamlessly surrounds the triaxial pressure chamber, so that the control of the test temperature is realized; splicing the mining well interface with a soil body sample, installing the mining well interface into a triaxial pressure chamber, and simulating the mechanical properties of the soil-well interface in the mining process; the data transmission acquisition processor is respectively connected with the triaxial pressure chamber, the air supply and pressure regulation system, the confining pressure loader, the axial pressure loader, the water bath tank and the back pressure valve, and periodically acquires test data and stores and processes the test data.
Compared with the prior art, the invention has the following beneficial effects:
1. the method can stably generate a soil body sample containing natural gas hydrate, and can realize the experimental study of the mechanical properties of a soil-well interface in the hydrate exploitation process;
2. the temperature rise and pressure reduction decomposition considering different decomposition times of the hydrate can be realized, and the influence of different exploitation working conditions on the mechanical properties of the soil-well interface can be simulated by pressure reduction or temperature rise alone;
3. the upper base and the lower base are composed of L-shaped perforated steel blocks and perforated soft silica gel, so that gas-liquid flow is ensured to enable natural gas hydrate to be smoothly generated and decomposed, and meanwhile, axial pressure is respectively transferred to a sample soil body and a well interface, and mutual shearing between the soil-well interface is realized;
4. the data is automatically acquired and calculated, the data acquisition precision is high, the degree of automation is high, and the manual error is reduced;
drawings
FIG. 1 is a schematic structural diagram of a device for testing mechanical properties of an earth-well interface in a simulated hydrate exploitation process;
FIG. 2 is a schematic diagram of an upper/lower pad and a soil-well interface sample of a device for simulating the mechanical properties of a soil-well interface during hydrate recovery;
FIG. 3 is a schematic diagram of a gas-liquid separation recovery device in a test device for simulating mechanical properties of a soil-well interface in a hydrate exploitation process.
In the figure: 1. the device comprises a triaxial pressure chamber, a triaxial pressure loader, a confining pressure loader, a soil-well interface sample, a gas supply and pressure regulation system, a water bath tank, a backpressure valve, a gas-liquid separation and recovery device and a data acquisition system.
Detailed Description
As shown in fig. 1, a test device for simulating mechanical properties of an ocean energy soil-well interface in a hydrate exploitation process comprises: the device comprises a triaxial pressure chamber 1, an axial pressure loader 2, a confining pressure loader 3, a soil-well interface shear sample 4, a gas supply and pressure regulation system 5, a water bath tank 6, a back pressure valve 7, a gas-liquid separation and recovery device 8 and a data acquisition system 9; wherein: the stress loading systems 2 and 3 are connected with the triaxial pressure chamber 1 to realize loading in different stress modes; the gas supply and pressure regulation system 5 is connected with the triaxial pressure chamber 1, and is used for providing a gas source and controlling the gas application pressure; the water bath tank 6 seamlessly surrounds the triaxial pressure chamber 1, and controls the temperature in the confining pressure chamber to realize stable generation of hydrate or temperature rising decomposition of the hydrate; the soil-well interface sample 4 is arranged in the triaxial pressure chamber 1 and simulates the soil-well interface mutual shearing action caused by exploitation; the back pressure valve 7 is connected with the triaxial pressure chamber 1, and the hydrate decomposition is controlled by adjusting the pressure of the back pressure valve; the gas-liquid separation and recovery device 8 is connected with the back pressure valve 7 and is used for metering and recovering gas and liquid; the data acquisition system 9 acquires test data at regular time and stores the test data.
The air supply and pressure regulating system 5 comprises a methane cylinder 51, a pressure regulating valve 52, a pressure gauge 53 and an air valve 54. The pressure regulating valve 52 is connected with the methane cylinder 51 to set the buffer container pressure, the pressure gauge 53 is used for measuring the air pressure, and the air valve 54 controls the air input.
The water bath tank 6 surrounds the triaxial pressure chamber 1 in a seamless manner, and the thermometer 61 can measure the internal temperature of the triaxial pressure chamber 1 so as to ensure accurate control of the temperature.
The back pressure valve 7 is connected with the sample through the lower cushion block 12, when the internal pressure of the sample is higher than the preset pressure of the back pressure valve 7, the gas is discharged through the back pressure valve 7 until the air pressure reaches the preset pressure, and the controllable decomposition of the hydrate can be realized by setting the pressure of the back pressure valve 7. The pressure gauge 71 is used to measure the gas outlet pressure in the pipeline; a gas-liquid valve 72 controls the gas-liquid output.
As shown in fig. 2, the triaxial pressure chamber 1 is provided with a lower cushion block 12, an upper base of a soil-well interface sample (L-shaped band Kong Gangkuai, semicircular perforated soft silica gel 44), a semi-cylindrical soil body sample 41, a well interface 42, and an upper base of a soil-well interface sample (L-shaped band Kong Gangkuai, semicircular perforated soft silica gel 44) from bottom to top. The upper cushion block 11 is connected with the air supply and pressure regulation system 5 through a pipeline 55. The lower spacer 12 is connected to a back pressure valve by line 73. The L-shaped perforated steel block 43 is uniformly provided with inner and outer layers of uniformly distributed round holes 432 with the diameter of 1mm, and the round holes 432 penetrate through the whole L-shaped perforated steel block 43. The perforated soft silica gel 44 is provided with 4 evenly distributed round holes 441 with diameters of 3mm, and the centers of the round holes correspond to the centers of the round holes of the inner layer of the L-shaped perforated steel block 43. The upper surface of the L-shaped perforated steel block 43 is provided with a groove 431 with the depth of 0.5mm, which is beneficial to methane gas circulation.
The overall height of the soil-well interface sample 4 is 100mm, and the diameter is 50mm; the semi-cylindrical soil body sample 41 has the same size as the well interface 42, and has a diameter of 50mm and a height of 60mm. The outer side of the soil-well interface sample 4 is wrapped with a heat-shrinkable rubber sleeve, and the upper end and the lower end of the heat-shrinkable rubber sleeve are respectively connected with an upper cushion block 11 and a lower cushion block 12 to ensure the sealing of the sample; in addition, the axial two sides of the thermal shrinkage rubber sleeve are provided with an axial strain sensor 45 and an axial displacement sensor 46, and the middle part of the outer surface is provided with a circumferential strain sensor 47.
The L-shaped perforated steel block 43 has high rigidity and is used for transmitting the axial pressure applied by the axial pressure loading system 2 to the semi-cylindrical soil body sample 41 and the well interface 42 so as to realize the mutual shearing between the soil body sample and the well interface; the semicircular perforated soft silica gel 44 has extremely small rigidity, does not influence the mutual dislocation during the shearing of the soil-well interface, and can keep the same confining pressure value in the heat shrinkage rubber sleeve and the triaxial pressure chamber 1 in the test process.
As shown in fig. 3, the gas-liquid separation and recovery device 8 includes a gas-liquid separator 81, a drying box 82, a gas flow meter 83, a gas recovery bottle 84, a liquid flow meter 85, and a liquid collection device 86. The gas-liquid separator 81 is connected to the back pressure valve 7 to separate the gas-liquid mixture; the liquid flows directly into the liquid recovery device 86 and the gas flows through the dry box 82 into the gas recovery device 84 and is metered. The gas flow meter 83 records the gas production rate and the cumulative gas production, thereby judging the production condition of the hydrate.
The test method for simulating the mechanical properties of the marine energy soil-well interface in the hydrate exploitation process adopts the measurement device and comprises the following steps:
1. mixing dry soil with deionized water to prepare an unsaturated semi-cylindrical soil sample with certain dry density and water content, attaching the unsaturated semi-cylindrical soil sample to a well interface, splicing the unsaturated semi-cylindrical soil sample with an upper base and a lower base, wrapping the unsaturated semi-cylindrical soil sample with a heat-shrinkable glue sleeve, and placing the unsaturated semi-cylindrical soil sample in a triaxial pressure chamber;
2. applying confining pressure to a preset pressure through a stress loading system, then injecting methane gas into a soil body sample to the preset pressure by using a gas supply and pressure regulation system, and maintaining the state to be ventilated for 24 hours to enable the methane gas to fill soil body pores;
3. setting the temperature of a water bath tank, reducing the temperature in the triaxial pressure chamber to the temperature (1 ℃) required by the reaction, gradually reducing the air pressure, and starting to generate hydrate; when the barometer shows that the air pressure is kept unchanged, the generation of the natural gas hydrate is completed;
4. the soil-well interface shear test before and after the decomposition of the hydrate and different decomposition times can be carried out respectively:
after the hydrate is generated, regulating the internal confining pressure of the triaxial pressure chamber to a preset value, then slowly applying axial load through a stress loading system, respectively transmitting axial pressure to a sample soil body and a well interface through a sample base, enabling the soil-well interface to generate shearing, and measuring circumferential strain data and axial strain data (shearing displacement) of the sample through a strain sensor.
After the hydrate is generated, heating and reducing pressure are carried out through a water bath tank and a back pressure valve to control the hydrate to decompose, the gas is discharged through the back pressure valve until the gas pressure in the sample reaches the preset gas pressure of the back pressure valve, the controllable decomposition of the hydrate is realized, and the hydrate-containing sample with different decomposition times can be obtained by controlling the decomposition time of the hydrate; after the hydrate is decomposed for a preset time, axial load is slowly applied through a stress loading system, axial pressure is respectively transmitted to a sample soil body and a well interface through a sample base, so that the soil-well interface is sheared, and circumferential strain data and axial strain data (shearing displacement) of the sample are measured through a strain sensor.
5. The influence of the hydrate exploitation process on the mechanical properties of the soil-well interface can be compared and analyzed through the shear data of the soil-well interface before and after the hydrate decomposition.
6. In addition, the conventional natural gas hydrate-containing soil mechanical property test can be carried out; and (3) replacing the whole soil-well interface sample with a pure soil body sample with the same size, synthesizing and decomposing the hydrate according to the steps, and carrying out a triaxial shear test of the natural gas-containing hydrate soil to simulate and analyze the mechanical properties of the soil body in the process of exploiting the hydrate.
Claims (7)
1. A method for testing mechanical properties of an ocean energy soil-well interface in a simulated hydrate exploitation process is provided, which adopts a device for testing mechanical properties of the ocean energy soil-well interface in the simulated hydrate exploitation process, and comprises the following steps: the device comprises a triaxial pressure chamber, an axial pressure loader, a confining pressure loader, an air supply pressure regulating system, a water bath tank, a back pressure valve, a gas-liquid separator, a gas-liquid recovery device and a data transmission acquisition processor; the gas pressure regulating system, the confining pressure loader and the axial pressure loader are respectively connected with the triaxial pressure chamber to realize gas pressure application and loading of different stress modes and different stress paths; the backpressure valve can control hydrate decomposition; the water bath tank seamlessly surrounds the triaxial pressure chamber, so that the control of the test temperature is realized; splicing the mining well interface with a soil body sample, installing the mining well interface into a triaxial pressure chamber, and simulating the mechanical properties of the soil-well interface in the mining process; the data transmission acquisition processor is respectively connected with the triaxial pressure chamber, the air supply pressure regulating system, the confining pressure loader, the axial pressure loader, the water bath tank and the back pressure valve, and periodically acquires test data and stores the test data;
the operation steps of the device for testing the mechanical properties of the marine energy soil-well interface in the process of simulating hydrate exploitation are as follows:
(1) Mixing dry soil with deionized water to prepare an unsaturated semi-cylindrical soil sample with certain dry density and water content, attaching the unsaturated semi-cylindrical soil sample to a well interface, splicing the unsaturated semi-cylindrical soil sample with an upper base and a lower base, wrapping the unsaturated semi-cylindrical soil sample with a heat-shrinkable glue sleeve, and placing the unsaturated semi-cylindrical soil sample in a triaxial pressure chamber;
(2) Applying confining pressure to a preset pressure through a stress loading system, then injecting methane gas into a soil body sample to the preset pressure by using a gas supply pressurizing system, carrying out leak detection, and standing to enable the methane gas to fill the soil body pores;
(3) Setting the temperature of a water bath tank, reducing the temperature in the triaxial pressure chamber to the temperature required by the reaction, gradually reducing the air pressure, and starting to generate hydrate; when the barometer shows that the air pressure is kept unchanged, the generation of the natural gas hydrate is completed;
(4) Respectively carrying out soil-well interface shear tests before and after hydrate decomposition and different decomposition times; after the hydrate is generated, regulating the internal confining pressure of the triaxial pressure chamber to a preset value, then slowly applying axial load through a stress loading system, respectively transmitting axial pressure to a sample soil body and a well interface through a sample base, enabling the soil-well interface to generate shearing, and measuring circumferential strain data and axial strain data of the sample through a strain sensor;
after the hydrate is generated, heating and reducing pressure are carried out through a water bath tank and a back pressure valve to control the hydrate to decompose, the gas is discharged through the back pressure valve until the gas pressure in the sample reaches the preset gas pressure of the back pressure valve, the controllable decomposition of the hydrate is realized, and the hydrate-containing sample with different decomposition times can be obtained by controlling the decomposition time of the hydrate; after the hydrate is decomposed for a preset time, slowly applying an axial load through a stress loading system, respectively transmitting axial pressure to a sample soil body and a well interface through a sample base, enabling the soil-well interface to generate shearing, and measuring circumferential strain data and axial strain data of the sample through a strain sensor;
(5) The influence of the hydrate exploitation process on the mechanical properties of the soil-well interface can be compared and analyzed through the shearing data of the soil-well interface before and after the hydrate decomposition;
(6) Carrying out a conventional natural gas hydrate-containing soil mechanical property test, changing the whole soil-well interface sample into a pure soil body sample with the same size, synthesizing and decomposing the hydrate according to the steps, carrying out a natural gas hydrate-containing soil triaxial shear test, and simulating and analyzing the mechanical property of the soil body in the process of exploiting the hydrate.
2. The method for testing mechanical properties of the marine energy soil-well interface in the process of simulating hydrate exploitation according to claim 1, wherein the method comprises the following steps of: the triaxial pressure chamber is provided with a lower cushion block, an upper base of a soil-well interface sample, a semi-cylindrical soil body sample, a well interface and an upper base of a soil-well interface sample from bottom to top; the upper cushion block is connected with the air supply pressure regulating system through a pipeline, the lower cushion block is connected with the back pressure valve through a pipeline, the L-shaped perforated steel block is uniformly provided with inner and outer layers of uniformly distributed round holes with the diameter of 1mm, the round holes penetrate through the whole L-shaped belt Kong Gangkuai, the perforated soft silica gel is provided with uniformly distributed round holes with the diameter of 3mm, the center of each round hole corresponds to the center of the round hole of the inner layer of the L-shaped perforated steel block, and the upper surface of the L-shaped perforated steel block is provided with a groove with the depth of 0.5mm, so that methane gas circulation is facilitated.
3. The method for testing mechanical properties of the marine energy soil-well interface in the process of simulating hydrate exploitation according to claim 1, wherein the method comprises the following steps of: the overall height of the soil-well interface sample is 100mm, and the diameter is 50mm; the semi-cylindrical soil body sample has the same size as the interface of the well, the diameter is 50mm, and the height is 60mm; the outer side of the soil-well interface sample is wrapped with a heat-shrinkable rubber sleeve, and the upper end and the lower end of the heat-shrinkable rubber sleeve are respectively connected with an upper cushion and a lower cushion block to ensure the sealing of the sample; in addition, two axial strain sensors are arranged on two axial sides of the heat-shrinkable rubber sleeve, and an annular strain sensor is arranged in the middle of the outer surface.
4. The method for testing mechanical properties of the marine energy soil-well interface in the process of simulating hydrate exploitation according to claim 1, wherein the method comprises the following steps of: the L-shaped perforated steel block has high rigidity and is used for transmitting the axial pressure applied by the axial pressure loading system to the semi-cylindrical soil body sample and the well interface so as to realize the mutual shearing between the soil body sample and the well interface; the semicircular perforated soft silica gel has extremely small rigidity, does not influence the mutual dislocation when the soil-well interface is sheared, and can keep the same confining pressure value in the heat shrinkage rubber sleeve and the triaxial pressure chamber in the test process.
5. The method for testing mechanical properties of the marine energy soil-well interface in the process of simulating hydrate exploitation according to claim 1, wherein the method comprises the following steps of: the water bath tank comprises a constant-temperature water bath and a thermometer; the water bath tank seamlessly surrounds the triaxial pressure chamber; the temperature application range value is-30 to 99.9 ℃.
6. The method for testing mechanical properties of the marine energy soil-well interface in the process of simulating hydrate exploitation according to claim 1, wherein the method comprises the following steps of: the back pressure valve is connected with the sample through the lower cushion block, the water bath tank system and the back pressure valve are used for heating and reducing pressure to control the decomposition of the hydrate, the gas is discharged through the back pressure valve until the pressure of the back pressure valve is equal to the pressure in the sample, the controllable decomposition of the hydrate is realized, and the hydrate-containing sample with different decomposition times can be obtained by controlling the decomposition time of the hydrate.
7. The method for testing mechanical properties of the marine energy soil-well interface in the process of simulating hydrate exploitation according to claim 1, wherein the method comprises the following steps of: the gas-liquid separation and recovery system comprises a gas-liquid separation meter, a gas flowmeter, a liquid flowmeter, a drying box, a gas collecting bottle and a liquid collecting device, wherein the gas-liquid separation meter is connected with a back pressure valve to separate a gas-liquid mixture; the liquid directly flows into the liquid recovery device, and the gas flows into the gas recovery device through the drying box and is metered; the gas flowmeter records the gas production rate and the accumulated gas production rate, thereby judging the exploitation condition of the hydrate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110924314.0A CN113622906B (en) | 2021-08-12 | 2021-08-12 | Testing device and testing method for simulating mechanical properties of ocean energy soil-well interface in hydrate exploitation process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110924314.0A CN113622906B (en) | 2021-08-12 | 2021-08-12 | Testing device and testing method for simulating mechanical properties of ocean energy soil-well interface in hydrate exploitation process |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113622906A CN113622906A (en) | 2021-11-09 |
| CN113622906B true CN113622906B (en) | 2023-12-29 |
Family
ID=78384883
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110924314.0A Active CN113622906B (en) | 2021-08-12 | 2021-08-12 | Testing device and testing method for simulating mechanical properties of ocean energy soil-well interface in hydrate exploitation process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113622906B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114837626A (en) * | 2022-03-29 | 2022-08-02 | 哈尔滨工程大学 | Device and method for replacing natural gas hydrate with stress-controllable carbon dioxide |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2396229A1 (en) * | 1977-06-28 | 1979-01-26 | Flopetrol Ste Auxil Prod Petro | SUBMARINE VALVE FOR SEA WELLS |
| CN101328050A (en) * | 2008-07-31 | 2008-12-24 | 中国石油大学(华东) | Low temperature low hydration heat cementing cement system |
| CN101435748A (en) * | 2007-11-15 | 2009-05-20 | 中国石化集团胜利石油管理局钻井工艺研究院 | Cable rotary type hydrate probe boring sampling apparatus |
| CN104453794A (en) * | 2014-11-20 | 2015-03-25 | 中国科学院广州能源研究所 | Simulation experiment system for whole process of natural gas hydrate exploitation and simulation method |
| CN109372499A (en) * | 2018-11-02 | 2019-02-22 | 广州海洋地质调查局 | A kind of geologic reservoir radial flow simulation system |
| CN111980673A (en) * | 2020-08-28 | 2020-11-24 | 中国石油大学(华东) | Testing device and testing method for simulating ocean energy soil-well coupling effect caused by hydrate exploitation |
| CN112748011A (en) * | 2019-10-31 | 2021-05-04 | 中国石油大学(华东) | Device and method for testing mechanical characteristics of contact surface of marine energy soil containing natural gas hydrate and structure |
-
2021
- 2021-08-12 CN CN202110924314.0A patent/CN113622906B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2396229A1 (en) * | 1977-06-28 | 1979-01-26 | Flopetrol Ste Auxil Prod Petro | SUBMARINE VALVE FOR SEA WELLS |
| CN101435748A (en) * | 2007-11-15 | 2009-05-20 | 中国石化集团胜利石油管理局钻井工艺研究院 | Cable rotary type hydrate probe boring sampling apparatus |
| CN101328050A (en) * | 2008-07-31 | 2008-12-24 | 中国石油大学(华东) | Low temperature low hydration heat cementing cement system |
| CN104453794A (en) * | 2014-11-20 | 2015-03-25 | 中国科学院广州能源研究所 | Simulation experiment system for whole process of natural gas hydrate exploitation and simulation method |
| CN109372499A (en) * | 2018-11-02 | 2019-02-22 | 广州海洋地质调查局 | A kind of geologic reservoir radial flow simulation system |
| CN112748011A (en) * | 2019-10-31 | 2021-05-04 | 中国石油大学(华东) | Device and method for testing mechanical characteristics of contact surface of marine energy soil containing natural gas hydrate and structure |
| CN111980673A (en) * | 2020-08-28 | 2020-11-24 | 中国石油大学(华东) | Testing device and testing method for simulating ocean energy soil-well coupling effect caused by hydrate exploitation |
Non-Patent Citations (1)
| Title |
|---|
| 浅议海洋矿产资源的可持续发展;于婷婷等;《海洋开发与管理》;第21-24页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113622906A (en) | 2021-11-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101813604B (en) | Device for testing durability of water pressure resistant grouted rock | |
| CN110487697B (en) | Supercritical carbon dioxide injection coal rock mechanical property test and fracturing experiment device | |
| CN109372499B (en) | Geological reservoir radial flow simulation system | |
| CN109236243B (en) | Three-dimensional comprehensive reservoir hydrate simulation analysis system and analysis method | |
| CN111504898B (en) | Experimental device and method for evaluating cement ring interface bonding strength under high-temperature and high-pressure conditions | |
| CN111289385B (en) | Device and method for detecting mechanical parameters of sediment containing hydrate based on X-CT | |
| CN107894383A (en) | Permeability measuring apparatus containing hydrate sediment and its method under condition of triaxial stress | |
| WO2017088226A1 (en) | Experimental apparatus and method for simulating stratum deformation in natural gas hydrate exploitation process | |
| CN111980673B (en) | Test device and test method for simulating marine energy soil-well coupling effect caused by hydrate exploitation | |
| CN104502264B (en) | Top-corrosion electrochemical testing device in high-temperature and high-pressure environments | |
| CN111735716A (en) | Rock temperature-stress coupling creep test device and test method under water environment | |
| CN105572014A (en) | Natural gas hydrate saturation and sediment permeability synchronous measurement device and method | |
| CN107727530B (en) | Application of integrated whole-course airtight gas content measuring instrument based on temperature and pressure backtracking principle | |
| CN203643307U (en) | Gas-liquid two-phase loop corrosion experiment device | |
| CN113622906B (en) | Testing device and testing method for simulating mechanical properties of ocean energy soil-well interface in hydrate exploitation process | |
| CN112282705A (en) | Evaluation device and experimental method for phase stability of drilling fluid additive to natural gas hydrate | |
| CN110749626A (en) | Device and method for measuring initial and final setting time of cement paste at high temperature and high pressure | |
| CN112505310A (en) | Test device and method for testing hydration heat release of cement slurry for well cementation | |
| CN202690036U (en) | High-temperature and high-pressure leakage-plugging test device for leakage of drilling liquid | |
| CN108894773A (en) | Supercritical CO2Pressure break cement gel junction fracturing experimental facilities and method | |
| CN112098231A (en) | Large triaxial mechanical test device and test method for simulating freeze-thaw cycle coarse-grained soil | |
| CN111042801A (en) | Device and method for measuring annulus cement slurry weight loss | |
| CN108181440B (en) | Experimental device for testing water quality index of reinjection water of large-scale underground water-sealed cave depot | |
| CN201794586U (en) | Well cementing wall packing channeling checking instrument | |
| CN114151041B (en) | Weak-cementing hydrate reservoir simulated wellbore construction device and method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |