Supercritical CO2 corrosion test system and test method thereof

Abstract

The embodiment of the invention relates to the technical field of corrosion resistance of test materials, in particular to a supercritical CO2 corrosion test system and a test method thereof. The supercritical CO2 corrosion test system comprises a sample loading device, a pressure regulating valve and an auxiliary pressure regulating part. The sample loading device is provided with a sample chamber for arranging a sample, and the sample chamber is also used for receiving the supercritical CO2 fluid, so that the sample in the sample chamber is subjected to a corrosion test under the supercritical CO2 atmosphere. The pressure regulating valve is arranged at the downstream of the sample chamber along the flowing direction of the supercritical CO2 fluid and is used for regulating the pressure of the sample chamber, so that a sample in the sample chamber is tested under a first preset pressure. The auxiliary pressure adjusting piece is used for increasing the pressure at the outlet of the pressure adjusting valve. By arranging the auxiliary pressure regulating part, the pressure difference between the inlet and the outlet of the pressure regulating valve is reduced, and the pressure of the sample chamber can be accurately regulated by the pressure regulating valve.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of testing the corrosion resistance of materials, and specifically to a supercritical CO 2 Corrosion test system and test method thereof. Background Art

[0002] The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

[0003] Supercritical carbon dioxide (S-CO 2 ) Brayton power conversion system is a new generation of power generation technology. In nuclear power power conversion system, supercritical CO 2 It usually has the characteristics of high temperature, high pressure, high flow rate, etc., which will cause corrosion to the material and thus affect the safe and efficient operation of the equipment. 2 Corrosion tests can provide a favorable basis for material selection. Reasonable material selection can effectively control the construction cost of reactor equipment. Therefore, supercritical CO 2 Corrosion testing is of great significance.

[0004] At present, there are already supercritical CO 2 Supercritical CO for corrosion testing 2 However, the current supercritical CO 2 Corrosion testing systems often have difficulty in accurately controlling the pressure in the sample chamber. Summary of the invention

[0005] A brief overview of the present application is provided below in order to provide a basic understanding of certain aspects of the present application. It should be understood that this overview is not an exhaustive overview of the present application. It is not intended to identify the key or important parts of the present application, nor is it intended to limit the scope of the present application. Its purpose is merely to present certain concepts in a simplified form as a prelude to a more detailed description discussed later.

[0006] In a first aspect, the embodiments of the present application provide a supercritical CO 2 The corrosion test system comprises: a sample loading device, which is configured to have a sample chamber for arranging a sample, and the sample chamber is also used to receive supercritical CO 2 fluid so that the sample in the sample chamber is heated to supercritical CO 2 Corrosion test was carried out in the atmosphere; pressure regulating valve, along the supercritical CO 2 The flow direction of the fluid is set downstream of the sample chamber, which is used to adjust the pressure of the sample chamber so that the sample in the sample chamber is tested at a first preset pressure; the auxiliary pressure regulating member is used to increase the pressure at the outlet of the pressure regulating valve.

[0007] In a second aspect, the present invention provides a supercritical CO 2 The corrosion test method is carried out using the device of the first aspect of the present application, and the method comprises: introducing supercritical CO into the sample chamber 2 , supercritical CO 2 The gas flows through the sample chamber, the pressure regulating valve and the auxiliary pressure regulating member in sequence and then enters the atmosphere; the pressure regulating valve is adjusted so that the pressure in the sample chamber is a first preset pressure; the auxiliary pressure regulating member is adjusted so that the pressure at the outlet of the pressure regulating valve is a second preset pressure, which is less than the first preset pressure and greater than the atmospheric pressure; then, supercritical CO 2 Corrosion testing.

[0008] The embodiment of the present application increases the pressure at the outlet of the pressure regulating valve by providing an auxiliary pressure regulating member, thereby reducing the pressure difference between the inlet and outlet of the pressure regulating valve. 2 The vaporization phase change occurring at the pressure regulating valve causes the pressure regulating valve to drop in temperature rapidly, thereby facilitating accurate control of the pressure regulating valve over the pressure of the sample chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Other objects and advantages of the present application will become apparent from the following description of the embodiments of the present application with reference to the accompanying drawings, and will help to provide a comprehensive understanding of the present application.

[0010] Figure 1 is a supercritical CO according to one embodiment of the present invention 2 Schematic diagram of the corrosion test system.

[0011] Figure 2 It is a cross-sectional schematic diagram of a sample loading device according to an embodiment of the present application.

[0012] Figure 3 yes Figure 2 A partial enlarged schematic diagram of the sample chamber of the sample loading device.

[0013] Figure 4 is a schematic cross-sectional view of a sample holding assembly according to an embodiment of the present application.

[0014] Figure 5 is a schematic exploded view of a sample holding assembly according to one embodiment of the present application.

[0015] Figure 6 It is a schematic top view of a retaining member according to an embodiment of the present application.

[0016] Description of reference numerals:

[0017] 1. Sample loading device;

[0018] 10. Sample room;

[0019] 20. Air inlet interface;

[0020] 30. Air outlet interface;

[0021] 40. Sample holding assembly; 41. Holding member; 411. Positioning groove group; 4111. Positioning groove; 41111. Middle groove area; 41112. End groove area; 412. Core; 413. Extension; 414. Center mounting hole; 415. Mounting hole outside the holding member; 42. Connecting assembly; 421. Connecting kit; 4211. Kit body; 4212. Clamping part; 422. Connecting fitting; 423. Fastener; 424. Gasket; 4241. Gasket mounting hole; 425. Connecting member;

[0022] 50. Samples;

[0023] 60. Rotation drive member; 61. Rotation shaft; 611. Rotation shaft interface; 62. Rotating drum; 621. Magnet; 622. Connecting drum; 63. Rotating drum cooling member; 64. Rotating shaft cooling member; 641. First cooling connection part; 642. Second cooling connection part; 643. Cooling body; 65. Driving mounting member; 66. Spacer; 661. First connection part; 662. Second connection part; 67. Driving member; 68. Bearing;

[0024] 70, body; 701, groove; 71, cover; 711, through hole; 72, fixing member; 73, stationary sample slot; 74, fastener;

[0025] 80. pressure regulating valve; 81. first temperature measuring element; 82. first electric heating element;

[0026] 90. Auxiliary pressure regulating element; 91. Auxiliary pressure regulating valve; 92. Pressure stabilizing vessel; 93. Pressure measuring element; 94. Auxiliary temperature measuring element; 95. Auxiliary electric heating element;

[0027] 101. Carbon dioxide gas supply component; 102. Gas source valve; 103. Replacement valve; 104. First pressure measuring component; 105. Precooling component; 106. Cold water supply component; 107. Filter component;

[0028] 110. Air intake pipe;

[0029] 121. Booster pump; 122. Valve; 123. Second pressure measuring device; 124. Check valve;

[0030] 131. Preheating parts; 132. Temperature control parts;

[0031] 141. Cooling element; 142. Second temperature measuring element; 143. Third pressure measuring element; 144. Exhaust valve; 145. Bursting disc; 146. Drain valve.

[0032] It should be noted that the drawings are not necessarily drawn to scale, but are merely shown in a schematic manner that does not affect the reader's understanding. DETAILED DESCRIPTION

[0033] Exemplary embodiments of the present application will be described below in conjunction with the accompanying drawings. For the sake of clarity and conciseness, not all features of the actual implementation are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the process of developing any such actual implementation in order to achieve the developer's specific goals, such as meeting those constraints related to the system and business, and these constraints may vary from implementation to implementation. In addition, it should be understood that although the development work may be very complex and time-consuming, it is only a routine task for those skilled in the art who benefit from the content of this application.

[0034] It is also necessary to explain here that, in order to avoid obscuring the present application due to unnecessary details, only the device structure and / or processing steps closely related to the scheme according to the present application are shown in the accompanying drawings, while other details that are not very relevant to the present application are omitted.

[0035] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in this application should have the common meanings understood by persons with ordinary skills in the field to which this application belongs.

[0036] In the description of the embodiments of the present application, “plurality” means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0037] High flow rate supercritical CO in related technology 2 In order to achieve high pressure conditions in the sample chamber of the corrosion test system, a pressure regulating valve (such as a back pressure valve) is usually installed downstream of the sample chamber, and the pressure in the sample chamber is adjusted by the pressure regulating valve to maintain the sample chamber at a high pressure condition.

[0038] CO flowing out of the pressure regulating valve 2 The gas flows directly into the atmosphere. The inventors of the present application have found that the pressure on one side of the pressure regulating valve is the same as the atmosphere, while the pressure on the other side is maintained at up to 25 MPa. 2 Pressure drop, CO 2 The phase change from liquid to gas occurs, absorbing a large amount of heat, causing the valve temperature to drop sharply and easily freeze, resulting in the pressure regulating valve not being accurate enough in regulating the pressure in the sample chamber.

[0039] In order to solve the above problem, an electric heater is provided to heat the pressure regulating valve to prevent it from freezing. The inventor of the present application found that the pressure regulating valve cools down very quickly, while the electric heater has a slow heating rate and a slow response speed, and it is difficult to provide enough heat in a short time to prevent the temperature of the pressure regulating valve from dropping suddenly.

[0040] Based on this, the embodiment of the present application provides a supercritical CO 2 Corrosion testing system. Figure 1 is a supercritical CO according to one embodiment of the present invention 2 Schematic diagram of the corrosion test system. Figure 1 As shown, supercritical CO 2 The corrosion test system includes: a sample loading device 1, a pressure regulating valve 80 and an auxiliary pressure regulating member 90. The sample loading device 1 is configured to have a sample chamber 10 for arranging a sample 50, and the sample chamber 10 is also used to receive supercritical CO 2 fluid, so that the sample 50 in the sample chamber 10 is in supercritical CO 2 The corrosion test was carried out in the atmosphere. The pressure regulating valve 80 was 2 The flow direction of the fluid is set downstream of the sample chamber 10 to adjust the pressure of the sample chamber 10 so that the sample 50 in the sample chamber 10 is tested at a first preset pressure. The auxiliary pressure regulating member 90 is used to increase the pressure at the outlet of the pressure regulating valve 80 .

[0041] In the embodiment of the present application, the auxiliary pressure regulating member 90 is provided to increase the pressure at the outlet of the pressure regulating valve 80, thereby reducing the pressure difference between the inlet and outlet of the pressure regulating valve 80. 2 The vaporization phase change occurring at the pressure regulating valve 80 causes the pressure regulating valve 80 to drop in temperature rapidly, thereby facilitating accurate control of the pressure of the sample chamber 10 by the pressure regulating valve 80 .

[0042] like Figure 1 As shown, the auxiliary pressure regulating member 90 includes an auxiliary pressure regulating valve 91 (such as a back pressure valve). The auxiliary pressure regulating valve 91 is along the supercritical CO 2 The flow direction of the fluid is set downstream of the pressure regulating valve 80, and the supercritical CO from the outlet of the pressure regulating valve 80 2 The fluid flows to the inlet of the auxiliary pressure regulating valve 91, and flows to the atmosphere from the outlet of the auxiliary pressure regulating valve 91. The auxiliary pressure regulating valve 91 is configured to regulate the pressure on the inlet side of the auxiliary pressure regulating valve 91 (i.e., the outlet side of the pressure regulating valve 80) to a second preset pressure, which is less than the first preset pressure and greater than the atmospheric pressure.

[0043] The auxiliary pressure regulating valve 91 reduces the pressure difference between the inlet and the outlet of the pressure regulating valve 80 by regulating the pressure at the outlet of the pressure regulating valve 80 to a second preset pressure greater than the atmospheric pressure.

[0044] Supercritical CO 2 The fluid flows from the outlet of the auxiliary pressure regulating valve 91 to the atmosphere.

[0045] like Figure 1 As shown, the auxiliary pressure regulating member 90 further includes a pressure stabilizing container 92. The pressure stabilizing container 92 is disposed on the flow path between the pressure regulating valve 80 and the auxiliary pressure regulating valve 91, and the auxiliary pressure regulating valve 91 regulates the pressure in the pressure stabilizing container 92. The provision of the pressure stabilizing container 92 is more conducive to the auxiliary pressure regulating valve 91 regulating the pressure.

[0046] In some embodiments, the pressure stabilizing container 92 may be a pressure-bearing container, and the pressure-bearing container may reach above 20 MPa.

[0047] In some embodiments, Figure 1 As shown, the auxiliary pressure regulating member 90 further includes a pressure measuring member 93. The pressure measuring member 93 is disposed on the flow path between the pressure stabilizing container 92 and the auxiliary pressure regulating valve 91, and is used to measure the pressure at the inlet of the auxiliary pressure regulating valve 91, so as to adjust the opening of the auxiliary pressure regulating valve 91 according to the pressure measured by the pressure measuring member 93.

[0048] In some embodiments, Figure 1 As shown, the auxiliary pressure regulating member 90 further includes an auxiliary temperature measuring member 94 and an auxiliary electric heating member 95. The auxiliary temperature measuring member 94 is used to measure the temperature of the auxiliary pressure regulating valve 91. The auxiliary electric heating member 95 heats the auxiliary pressure regulating valve 91 according to the temperature measured by the auxiliary temperature measuring member 94, so as to heat the temperature of the auxiliary pressure regulating valve 91 to a preset temperature.

[0049] The temperature of the pressure regulating valve 80 measured by the auxiliary temperature measuring element 94 and the preset temperature serve as the basis for the auxiliary electric heating element 95 to heat the auxiliary pressure regulating valve 91. This arrangement helps to maintain the temperature of the auxiliary pressure regulating valve 91 at the preset temperature, so that the pressure regulating effect of the auxiliary pressure regulating valve 91 is better; even if supercritical CO appears in the auxiliary pressure regulating valve 91 2 The vaporization phase transition (if supercritical CO 2 The auxiliary pressure regulating valve 91 can also be slowly raised in temperature by providing heat. Since the auxiliary temperature measuring member 94 adjusts the pressure on the inlet side of the auxiliary pressure regulating valve 91, the pressure does not need to be particularly accurate, even if supercritical CO appears in the auxiliary pressure regulating valve 91. 2The vaporization phase change may cause the auxiliary pressure regulating valve 91 to freeze, but it will not affect the effect of the auxiliary temperature measuring member 94 on regulating the pressure on the inlet side of the auxiliary pressure regulating valve 91.

[0050] like Figure 1 As shown, supercritical CO 2 The corrosion test system also includes: a first temperature measuring component 81 and a first electric heating component 82. The first temperature measuring component 81 is used to measure the temperature of the pressure regulating valve 80. The first electric heating component 82 heats the pressure regulating valve 80 according to the temperature measured by the first temperature measuring component 81, so as to heat the temperature of the pressure regulating valve 80 to a preset temperature. In the embodiment of the present application, the auxiliary pressure regulating component 90 is provided to reduce the pressure difference between the inlet and outlet of the pressure regulating valve 80, so as to avoid the phase change inside the pressure regulating valve 80, thereby preventing the temperature from dropping suddenly and causing ice. When the pressure regulating valve 80 is filled with supercritical CO 2 When the fluid pressure drop causes the temperature to drop slightly, the first temperature measuring element 81 and the first electric heating element 82 are used to help maintain the temperature of the pressure regulating valve 80 at a preset temperature, so that the pressure regulating valve 80 can better regulate the pressure of the sample chamber 10.

[0051] In some embodiments, the preset temperature may be higher than the room temperature to ensure the pressure regulating effect of the pressure regulating valve 80 and the auxiliary pressure regulating member 90. For example, the preset temperature may be 30-50°C.

[0052] In some embodiments, the second preset pressure may be greater than CO 2 The saturated vapor pressure corresponding to the temperature at room temperature. At room temperature of 20°C, the saturated vapor pressure of carbon dioxide is about 5MPa. When the second preset pressure is greater than CO 2 When the saturated vapor pressure corresponds to the room temperature, the CO inside the pressure regulating valve 80 2 The vaporization is not violent, and the heat absorption will not be violent accordingly, so there will be no sudden drop in temperature and freezing.

[0053] Therefore, when the first electric heating element 82 heats the temperature of the pressure regulating valve 80 to a preset temperature, the auxiliary pressure regulating valve 91 adjusts the pressure at the outlet of the pressure regulating valve 80 to above 5 MPa, which can effectively prevent the pressure regulating valve 80 from freezing due to the temperature being too low, and ensure that the pressure regulating valve 80 accurately regulates the pressure of the sample chamber 10.

[0054] The test found that, without using the auxiliary pressure regulating valve 91 to increase the pressure at the outlet of the pressure regulating valve 80, the pressure regulating accuracy of the pressure regulating valve 80 is ±1MPa; when the pressure at the outlet of the pressure regulating valve 80 is increased by using the auxiliary pressure regulating valve 91, the pressure regulating accuracy of the pressure regulating valve 80 can reach ±0.5MPa. It can be seen that the present application improves the pressure regulating accuracy of the pressure regulating valve 80 by setting the auxiliary pressure regulating valve 91.

[0055] In some embodiments, supercritical CO 2 The corrosion test system further includes a carbon dioxide supply component 101 , an air intake pipeline 110 , a precooling component 105 , a booster pump 121 , a preheating component 131 and a cooling component 141 .

[0056] The air intake pipeline 110 is connected to the air intake interface 20, and the carbon dioxide supply part 101 is used to provide gaseous carbon dioxide to the air intake pipeline 110 so that the gaseous carbon dioxide is input into the air intake pipeline 110. The booster pump 121, the precooling part 105, the preheating part 131 and the cooling part 141 are respectively arranged on the air intake pipeline 110. The carbon dioxide supply part 101 can be a carbon dioxide gas cylinder. The air intake pipeline 110 is a high-pressure pipeline.

[0057] The booster pump 121 is used to pressurize the liquid carbon dioxide in the intake pipe 110 to a supercritical CO 2 The test pressure of the corrosion test is to provide the high-pressure supercritical CO required for the test. 2 Since the booster pump 121 can only drive liquid carbon dioxide, a precooling member 105 is provided upstream of the booster pump 121 . The precooling member 105 is used to reduce the temperature of carbon dioxide in the air intake line 110 to liquefy gaseous carbon dioxide so as to be driven by the booster pump 121 .

[0058] The preheating element 131 is disposed downstream of the booster pump 121 to heat the supercritical CO 2 Preheat to supercritical CO 2 The test temperature is similar to that of the corrosion test to provide the high temperature and high pressure supercritical CO required for the test. 2 , for example 600°C. After preheating, high temperature and high pressure supercritical CO 2 The liquid enters the sample chamber 10, is further heated to the test temperature in the sample chamber 10, and flows out of the sample chamber 10 after passing through the sample 50. The preheating element 131 may be an electric heating element.

[0059] The cooling element 141 is disposed in the downstream pipeline of the sample chamber 10 and is used to cool the high-temperature supercritical CO 2 The temperature is lowered to below 40°C to avoid adverse effects on downstream valves. The supercritical CO flowing out of the cooling element 141 2After entering the pressure regulating valve 80, the pressure stabilizing container 92 and the auxiliary pressure regulating component 90 in sequence, it enters the atmospheric environment.

[0060] In some embodiments, a gas source valve 102 is further provided in the air intake pipeline 110 , and the supply and interruption of gaseous carbon dioxide are achieved by opening and closing the gas source valve 102 .

[0061] In some embodiments, supercritical CO 2 The corrosion test system further includes a replacement valve 103 , which is disposed in a pipeline connected in parallel with the air intake pipeline 110 and is used to replace air impurities introduced during the replacement of the carbon dioxide supply component 101 .

[0062] In some embodiments, a first pressure measuring element 104 is further provided in the air intake line 110. The first pressure measuring element 104 is provided upstream of the precooling element 105 and is used to detect the pressure at the inlet of the precooling element 105 and to alarm when the pressure at the inlet of the precooling element 105 is too low. The first pressure measuring element 104 may be a digital pressure sensor.

[0063] In some embodiments, supercritical CO 2 The corrosion test system further includes a cold water providing component 106 , which is disposed on the pre-cooling component 105 and is used to provide the cooling capacity required by the pre-cooling component 105 , thereby controlling the temperature of the carbon dioxide in the air intake pipeline 110 .

[0064] In some embodiments, a filter 107 is further provided in the air intake pipeline 110, and the filter 107 is provided between the precooling element 105 and the booster pump 121, and is used to remove impurities in the liquid carbon dioxide, thereby obtaining clean liquid carbon dioxide. The filter 107 may be a 15 μm sintered T-type filter.

[0065] In some embodiments, a second pressure measuring device 123 is also provided in the intake pipe 110. The second pressure measuring device 123 is provided downstream of the boost pump 121 and is used to detect the pressure at the outlet of the boost pump 121. When the pressure at the outlet of the boost pump 121 is too high, an alarm is issued, thereby preventing the boost pump 121 from malfunctioning due to excessive pressure at the outlet.

[0066] In some embodiments, a valve 122 and a one-way valve 124 are further provided in the air intake line 110, and the valve 122 and the one-way valve 124 are sequentially provided downstream of the second pressure measuring element 123. The valve 122 is used to control the flow of liquid carbon dioxide in the air intake line 110; the one-way valve 124 is used to prevent the liquid carbon dioxide from flowing in the reverse direction in the air intake line 110. The second pressure measuring element 123 may be a digital pressure sensor.

[0067] In some embodiments, supercritical CO 2The corrosion test system further includes a temperature control unit 132 , which is disposed on the preheating element 131 and is used to display the temperature of the preheating element 131 so that the preheating element 131 adjusts the heating power according to the temperature measured by the temperature control unit 132 .

[0068] In some embodiments, a cold water providing component 106 is disposed on the cooling component 141 , and the cold water providing component 106 provides a source of cold energy for the cooling component 141 .

[0069] In some embodiments, a second temperature measuring element 142 is further provided in the intake pipe 110, and the second temperature measuring element 142 is provided downstream of the cooling element 141. The second temperature measuring element 142 is used to detect the supercritical CO 2 temperature, and after cooling the supercritical CO 2 When the temperature exceeds 40℃, an alarm will sound.

[0070] In some embodiments, supercritical CO 2 The corrosion test system further includes a third pressure measuring device 143, a drain valve 146 and a bursting disc 145. The third pressure measuring device 143, the drain valve 146 and the bursting disc 145 are sequentially arranged in another parallel pipeline of the intake pipeline 110. The third pressure measuring device 143 is used to measure the pressure in the parallel pipeline, and the opening and closing of the drain valve 146 are controlled according to the pressure measured by the third pressure measuring device 143. The opening and closing of the drain valve 146 controls the CO in the pipeline. 2 The third pressure measuring member 143 may be a digital pressure sensor. The bursting disc 145 bursts at a predetermined temperature and pressure to release the pressure, thereby preventing equipment failure caused by excessive internal pressure of the parallel pipeline.

[0071] In some embodiments, an exhaust valve 144 is further provided in the air intake line 110. The exhaust valve 144 is provided downstream of the second temperature measuring element 142. By controlling the opening and closing of the exhaust valve 144, the supercritical CO 2 flow.

[0072] Figure 2 is a cross-sectional schematic diagram of a sample loading device 1 according to an embodiment of the present application, Figure 3 yes Figure 2 A partial enlarged schematic diagram of the sample chamber of the sample loading device. Figure 2 and Figure 3 As shown, the sample loading device 1 may include: a sample chamber 10; an air inlet interface 20, an air outlet interface 30, a sample holding assembly 40, and a rotating drive member 60. The air inlet interface 20 is used to introduce supercritical CO into the sample chamber 10. 2 The gas outlet interface 30 is used to transfer the supercritical CO in the sample chamber 10 2The gas flows out of the sample chamber 10. The sample holding assembly 40 is disposed in the sample chamber 10 and is used to hold a plurality of samples 50. The rotating drive 60 is used to drive the sample holding assembly 40 to rotate, so that the supercritical CO in the sample chamber 10 2 Capable of flowing along the surface of sample 50 at high speed.

[0073] In the embodiment of the present application, the sample holding assembly 40 is driven to rotate by the rotating driving member 60, so that the sample 50 has a certain linear velocity, thereby increasing the supercritical CO in the sample chamber 10. 2 For the relative flow rate of sample 50, supercritical CO 2 It can flow at high speed along the surface of the sample 50, thereby achieving high flow rate supercritical CO of the sample 50 2 Corrosion testing.

[0074] Figure 4 is a cross-sectional schematic diagram of a sample holding assembly 40 according to one embodiment of the present application, Figure 5 4 is a schematic diagram of an exploded view of a sample holding assembly 40 according to an embodiment of the present application.

[0075] like Figure 4 and Figure 5 As shown, in some embodiments, the sample holding assembly 40 may include two holders 41 and a connecting assembly 42 that are arranged opposite to each other. A plurality of positioning grooves 4111 are formed on each holder 41, and the sample 50 is a disc-shaped sample 50, and each disc-shaped sample 50 is inserted and held in the positioning grooves 4111 corresponding to the two holders 41. The connecting assembly 42 is used to connect the two holders 41 with the rotating driving member 60. In such an embodiment, the rotating driving member 60 is connected to the two holders 41 through the connecting assembly 42, so that the disc-shaped sample 50 inserted and held in the positioning grooves 4111 corresponding to the two holders 41 can be rotated, so that the disc-shaped sample 50 has a certain linear speed. The rotating driving member 60 drives the disc-shaped sample 50 relative to the supercritical CO 2 Do relative motion, so there is no need to directly provide high flow rate CO 2 , reducing CO 2 The load of filling, storage, heat exchange and other equipment has greatly reduced the equipment manufacturing cost.

[0076] In some embodiments, the two retaining members 41 have the same structure. The retaining members 41 may be an upper six-claw type fixture plate and a lower six-claw type fixture plate.

[0077] Figure 6 FIG. 4 is a schematic top view of a retaining member 41 according to an embodiment of the present application. Figure 6As shown, the retaining member 41 forms a plurality of positioning groove groups 411 distributed along its circumference, and each positioning groove group 411 includes a plurality of positioning grooves 4111 at different distances from the rotation axis of the retaining member 41; the distance between a positioning groove 4111 in each positioning groove group 411 and the rotation axis is the same as the distance between a corresponding positioning groove 4111 in any other positioning groove group 411 and the rotation axis.

[0078] Since the distance between a positioning slot 4111 in each positioning slot group 411 and the rotation axis is the same as the distance between a corresponding positioning slot 4111 in any other positioning slot group 411 and the rotation axis, multiple positioning slot groups 411 allow the number of samples 50 with the same linear speed to be multiple, thereby increasing the number of samples 50 with the same linear speed.

[0079] Since each positioning groove group 411 includes a plurality of positioning grooves 4111 at different distances from the rotation axis of the holder 41, and the plurality of positioning grooves 4111 in each positioning groove group 411 are arranged on the same horizontal axis passing through the rotation axis, the plurality of samples 50 arranged in one positioning groove group 411 have the same angular velocity and different linear velocities, so that the samples can be simulated in different supercritical CO in one test. 2 Corrosion testing was performed under flow rate conditions.

[0080] In some embodiments, each positioning groove 4111 includes a middle groove area 41111 and end groove areas 41112 arranged at both ends of the middle groove area 41111 along its length direction. The width of the middle groove area 41111 is greater than the width of the end groove area 41112. The length direction of the positioning groove 4111 is perpendicular to the radial direction of the retaining member 41. The entire length of the positioning groove 4111 is less than the diameter of the disc-shaped sample 50; the width of the end groove area 41112 is greater than the thickness of the disc-shaped sample 50, so that when the disc-shaped sample 50 is inserted into the positioning groove 4111, the contact surface between the positioning groove 4111 and the disc-shaped sample 50 is "line contact" rather than "surface contact", which can reduce the contact surface between the positioning groove 4111 and the disc-shaped sample 50, so that the disc-shaped sample 50 is less disturbed by the sample positioning groove 4111 during the test; the disc-shaped sample 50 and the supercritical CO 2 The contact area of ​​the disc-shaped sample 50 is larger, so that the contact area between the disc-shaped sample 50 and the supercritical CO 2 More responsive.

[0081] like Figure 4As shown, the holder 41 includes a core 412 and a plurality of extensions 413 connected to the core 412 along the periphery of the core 412, and each positioning groove group 411 is arranged at a corresponding extension 413. Such an arrangement is conducive to reducing the overall weight of the holder 41 while ensuring that the number of test samples 50 remains unchanged, thereby reducing unnecessary friction and inertia when the rotating drive member 60 drives the holder 41 to rotate, and further reducing the energy consumption required for the rotating drive member 60 to drive the holder 41 to rotate. At the same time, reducing the overall weight of the holder 41 also helps to make the rotating drive member 60 drive the holder 41 more stable, thereby ensuring the stability of the rotating drive member 60 when driving the sample 50 to rotate.

[0082] In some embodiments, the extension 413 extends radially outward from the core 412 .

[0083] In some embodiments, each extension portion 413 has the same shape, and each extension portion 413 is axially symmetrically arranged with respect to the rotation axis.

[0084] In some embodiments, the number of extensions 413 may be 6, and the angle between two adjacent extensions 413 is 60°. This arrangement allows the holder 41 to be subjected to balanced force in the horizontal direction, prevents the holder 41 from tilting in the horizontal direction, and enables the holder 41 to achieve stable horizontal rotation.

[0085] In some embodiments, the number of positioning grooves 4111 in each extension portion 413 may be 2-6.

[0086] In some embodiments, the distance between the positioning groove 4111 farthest from the rotation axis in each extension portion 413 and the rotation axis may be 80 mm, and the distance between two adjacent positioning grooves 4111 in the same extension portion 413 may be one tenth of the above distance, namely 8 mm.

[0087] In some embodiments, the rotation speed of the sample holding assembly 40 driven by the rotary drive 60 can reach 1000 r / min, for example, 1800 r / min. The sample 50 held by the sample holding assembly 40 is relatively stable relative to the supercritical CO 2 The flow rate can be greater than 5m / s.

[0088] like Figure 5As shown, the rotary drive member 60 includes a rotary shaft 61, and a central mounting hole 414 is formed at the center of each holder 41. The connecting assembly 42 may include: a connecting kit 421, a connecting fitting 422, and a fastener 423. The connecting kit 421 and the connecting fitting 422 are respectively arranged on the opposite sides of the two holders 41, and the connecting kit 421 enters the two central mounting holes 414, and the connecting kit 421 is detachably connected to the rotary shaft 61. The fastener 423 detachably connects the connecting fitting 422 to the rotary shaft 61 to connect the two holders 41 and connect the two holders 41 to the rotary shaft 61. The connecting assembly 42 connects the two holders 41, realizes the fixation of the two holders 41 and the stable clamping of the sample 50. At the same time, the connecting assembly 42 connects the two holders 41 to the rotary drive member 60, so as to realize the driving of the two holders 41 by the rotary drive member 60. In this way, while the sample holding assembly 40 and the rotating shaft 61 are being assembled and disassembled, the sample 50 and the sample holding assembly 40 are also being assembled and disassembled, thereby simplifying the assembly and disassembly operations.

[0089] In some embodiments, the rotating shaft 61 is provided with a rotating shaft interface 611, and the rotating shaft interface 611 is configured as a hollow cylinder, which is used to achieve a detachable connection with the connecting kit 421 and the fastener 423. In some embodiments, the rotating shaft interface 611 is inserted into the connecting kit 421, and the rotating shaft interface 611 is detachably connected to the connecting kit 421. In some embodiments, the detachable connection between the rotating shaft interface 611 and the connecting kit 421 can be a threaded connection. In some embodiments, the detachable connection between the rotating shaft interface 611 and the connecting kit 421 can be a threaded connection.

[0090] In some embodiments, the connection kit 421 includes a kit body 4211 and a clamping portion 4212 disposed on the kit body. The outer diameter of the clamping portion 4212 is larger than the inner diameter of the center mounting hole 414, and is used to clamp on one side of the rotating shaft 61 of the retaining member 41. The connecting fitting 422 is a circular ring, and the outer diameter of the circular ring is larger than the inner diameter of the center mounting hole 414. The clamping portion 4212 and the connecting fitting 422 are used to clamp the two retaining members 41 respectively. The size of the kit body 4211 is less than or equal to the inner diameter of the center mounting hole 414, so that it can enter the center mounting hole 414. The rotating shaft interface 611 of the rotating shaft 61 enters the kit body 4211 and is threadedly connected to the kit body 4211; the fastener 423 passes through the connecting fitting 422 from the other side and enters the rotating shaft interface 611 and is threadedly connected to the rotating shaft interface 611.

[0091] In some embodiments, the fastener 423 may be a locking screw, and the connection fitting 422 may be a locking washer. For example, the fastener 423 is an M6 hexagon socket locking screw.

[0092] The holder 41 may be a ceramic member.

[0093] like Figure 5 As shown, the connection assembly 42 also includes a gasket 424, which is arranged between the two retaining members 41, and the gasket 424 is provided with a gasket mounting hole 4241. The connection kit 421 enters the two central mounting holes 414 and the gasket mounting hole 4241. A plurality of connectors 425 connect the two retaining members 41 on the radial outer side of the gasket 424. A gasket 424 is arranged between the two retaining members 41, so that the distance between the two retaining members 41 remains unchanged when the sample holding assembly 40 is driven to rotate, thereby ensuring the stability of the sample 50 between the two retaining members 41. At the same time, by setting the height of the gasket 424, the sample 50 can be movably arranged in the positioning grooves 4111 of the two retaining members 41, preventing the sample 50 from being subjected to a large stress applied by the retaining member 41, thereby avoiding damage to the sample 50.

[0094] In some embodiments, the cross-sections of the central mounting hole 414 , the gasket mounting hole 4241 , and the kit body 4211 are all hexagonal to prevent the kit body 4211 and the retaining member 41 from rotating relative to each other.

[0095] In some embodiments, the retaining member 41 is provided with a plurality of retaining member outer mounting holes 415 on the radial outer side of the gasket 424 , and each retaining member 41 mounting hole is used for a connecting member 425 to enter.

[0096] In some embodiments, the connector 425 may be a screw and a nut. For example, when the screw is an M6 hexagon socket fixing screw, the nut is an M6 hexagon socket fixing nut.

[0097] like Figure 2 As shown, the rotating drive member 60 may further include: a driving member 67, a rotating drum 62 and a magnet 621. The driving member 67 drives the rotating drum 62 to rotate, and the magnet 621 is disposed on the rotating drum 62. The rotating shaft 61 is disposed on the radial inner side of the rotating drum 62 and the magnet 621, so as to rotate together with the rotating drum 62 under the magnetic force of the magnet 621. A bearing 68 is disposed between the rotating shaft 61 and the rotating drum 62. The driving member 67 may be a rotating motor. In theory, by adjusting the speed of the rotating motor, the sample can obtain a relative supercritical CO 2 Any linear speed.

[0098] In some embodiments, the rotary drive member 60 may further include: a connecting cylinder 622 connected to the rotating cylinder 62 , and the magnet 621 may be disposed on the connecting cylinder 622 .

[0099] In some embodiments, the rotation speed of the rotating drum 62 driven by the rotating driving member 60 can exceed 1000r / min (e.g., 1800r / min), and the continuous rotation time can reach several thousand hours (e.g., one year). When the rotating drum 62 rotates at a high speed for a long time, the magnet 621 disposed on the rotating drum 62 will gradually heat up, and the magnet 621 will be demagnetized when the temperature is too high, so that the driving member 67 cannot drive the rotating shaft 61 to rotate. In order to solve this problem, the rotating driving member 60 can also include: a rotating drum cooling member 63, which is used to cool the rotating drum 62 and the magnet 621 to prevent the magnet 621 from being demagnetized, thereby ensuring that the sample loading device 1 can be used for a long time.

[0100] like Figure 2 As shown, the sample loading device 1 may further include a body 70 and a cover 71. The body 70 has a top opening. The cover 71 is used to close the top opening to form a sample chamber 10 together with the body 70. The rotating shaft 61 passes through the cover 71 and enters the sample chamber 10. A bearing 68 is provided between the rotating shaft 61 and the cover 71. The bearing 68 may be disposed on a bearing seat and then connected to the cover 71 via a fastener 74.

[0101] The sample 50 may be a disc sample with a diameter of 16 mm and a thickness of 1 mm.

[0102] The sample loading device 1 of the embodiment of the present application can set the volume of the sample chamber 10 to be smaller, such as about 1L, which can effectively reduce heat loss, reduce carbon dioxide consumption, and eliminate interference caused by differences in test temperature of samples at different positions due to excessive volume and excessive length of the test section.

[0103] When the volume of the sample chamber 10 is set to about 1 L, supercritical CO 2 The theoretical value of carbon dioxide consumption per corrosion test run is 0.1kg; compared with the high flow rate CO provided by related technologies 2 The high-flow supercritical carbon dioxide corrosion test device, the theoretical value of carbon dioxide consumption per operation of the former is one thousandth of the latter.

[0104] The rotating drive member 60 further includes a shaft cooling member 64 for cooling the rotating shaft 61. The shaft cooling member 64 is connected to the cover 71 below the rotating cylinder 62. The shaft cooling member 64 is used to reduce the temperature of the surface of the rotating shaft 61 to prevent the heat in the sample chamber 10 from diffusing to the magnet 621 and preventing the magnet 621 from being demagnetized.

[0105] The air inlet interface 20 and the air outlet interface 30 are respectively formed on the cover body 71 and penetrate the cover body 71. The air inlet interface 20 and the air outlet interface 30 can be arranged on both sides of the rotating shaft 61 in the radial direction.

[0106] like Figure 2As shown, in some embodiments, the device further includes a fixing member 72. The cover 71 is provided with a through hole 711, and the body 70 is provided with a groove 701 corresponding to the through hole 711 of the cover 71. The fixing member 72 passes through the through hole 711 of the cover 71 and is detachably connected to the corresponding groove 701 of the body 70, so as to realize the combination and disassembly of the cover 71 and the body 70.

[0107] In some embodiments, the body 70 is provided with a heating element and a temperature measuring element. The heating element is used to heat the sample chamber 10 so that the supercritical CO in the sample chamber 10 2 The temperature measuring element is used to measure the temperature of the sample chamber 10, so that the heating element adjusts the heating power according to the temperature measured by the temperature measuring element. The heating element of the body 70 can be an electric heating element.

[0108] In some embodiments, the fixing member 72 may be a nut and a bolt, which is used to achieve a fastening connection between the cover 71 and the body 70 .

[0109] like Figure 3 As shown, in some embodiments, the bottom wall of the sample chamber 10 is provided with a static sample slot 73, and the static sample slot 73 is arranged directly below the rotating shaft 61. The static sample slot 73 is used to place the sample 50. During the test, the sample 50 is directly below the rotating shaft 61, and the airflow in the sample chamber 10 is the smallest, which is equivalent to the sample 50 being in a static state.

[0110] like Figure 2 As shown, the rotating driving member 60 also includes a driving mounting member 65 and a spacer 66. The driving member 67 and the drum cooling member 63 are arranged on the driving mounting member 65. The spacer 66 is connected to the shaft cooling member 64 and the driving mounting member 65, and the spacer 66 is arranged between the rotating shaft 61 and the drum 62. A bearing 68 is arranged between the connecting cylinder 622 and the spacer 66 to improve the stability of the rotation of the drum 62 and the magnet 621.

[0111] The shaft cooling member 64 is connected to the spacer sleeve 66 , and the shaft cooling member 64 supports the spacer sleeve 66 and the driving mounting member 65 .

[0112] The shaft cooling element 64 and the drum cooling element 63 can be cooled by water.

[0113] In some embodiments, the spacer 66 forms a first connection portion 661 and a second connection portion 662. The first connection portion 661 is disposed between the rotating shaft 61, the rotating drum 62 and the magnet 621, and the second connection portion 662 is used to connect the rotating shaft cooling member 64 and the driving mounting member 65, so as to achieve a stable connection between the rotating shaft cooling member 64 and the driving mounting member 65.

[0114] In some embodiments, the shaft cooling member 64 forms a first cooling connection portion 641, a cooling body 643 and a second cooling connection portion 642. The first cooling connection portion 641 is connected to the second connection portion 662 of the spacer 66. The cooling body 643 is disposed outside the rotating shaft 61 to reduce the surface temperature of the rotating shaft 61. The second cooling connection portion 642 is connected to the cover 71.

[0115] By setting the first cooling connection part 641, the rotating driving member 60 can be installed on the cover body 71 as a whole, and the cover body 71 and the rotating driving member 60 can be moved as a whole, thereby facilitating the disassembly and assembly of the sample holding assembly 40; and the heat in the sample chamber 10 will not be transferred to the magnet 621.

[0116] The present application also provides a supercritical CO 2 The corrosion test method uses the supercritical CO 2 Corrosion test system. The test method includes: introducing supercritical CO into the sample chamber 10 2 , supercritical CO 2 The gas flows through the sample chamber 10, the pressure regulating valve 80 and the auxiliary pressure regulating member 90 in sequence and then enters the atmosphere; the pressure regulating valve 80 is adjusted so that the pressure in the sample chamber is a first preset pressure; the auxiliary pressure regulating member 90 is adjusted so that the pressure at the outlet of the pressure regulating valve 80 is a second preset pressure, which is less than the first preset pressure and greater than the atmospheric pressure; then, supercritical CO 2 Corrosion testing.

[0117] In the method of the embodiment of the present application, the pressure in the sample chamber 10 is adjusted by the pressure regulating valve 80 so that the pressure in the sample chamber 10 is maintained at a preset pressure, so that the sample chamber 10 is maintained at a supercritical CO 2 The high pressure condition required for the corrosion test; the auxiliary pressure regulating member 90 is used to increase the pressure at the outlet of the pressure regulating valve 80 to a second preset pressure, so as to reduce the pressure difference between the inlet and outlet of the pressure regulating valve 80, thereby avoiding the supercritical CO 2 The vaporization phase change occurs at the pressure regulating valve 80, causing the pressure regulating valve 80 to drop sharply, which is conducive to ensuring that the pressure regulating valve 80 accurately controls the pressure of the sample chamber 10, so that the supercritical CO in the sample chamber 10 2 The pressure remains stable.

[0118] In some embodiments, supercritical CO 2 Before the corrosion test, all heating elements were turned on to transfer supercritical CO 2 Heating to the preheating temperature; turning on the rotating drive member 60, driving the sample holding assembly 40 to rotate to a preset speed, and starting the supercritical CO 2 Corrosion testing.

[0119] The following further describes the system of the present invention for supercritical CO with reference to the accompanying drawings and specific embodiments. 2 Corrosion test process and test methods.

[0120] 1. Safety inspection: After the equipment is powered on, check whether the display status of each measuring component is normal, whether the water level of the cold water supply component 106 is normal, close all valves, and check whether all test parameters and alarm parameters of the equipment are set normally.

[0121] 2. Place the sample: Assemble the sample 50 , the sample holding assembly 40 and the shaft interface 611 on the cover 71 , and then place the sample holding assembly 40 into the body 70 .

[0122] 3. Sealing the sample chamber 10: Check whether there are solid particles or debris on the contact surface between the cover 71 and the body 70, check whether the fixing member 72 is installed correctly, and use the fixing member 72 to fasten the cover 71 and the body 70 to seal the sample chamber 10.

[0123] 4. Carbon dioxide intake: The carbon dioxide supply component 101 provides gaseous carbon dioxide to the intake pipeline 110, the gas source valve 102 is opened, the introduced air is discharged through the replacement valve 103, and the first pressure measuring component 104 is observed to be normal. The valve 122 is slowly opened to inject carbon dioxide into the sample chamber 10, and the second pressure measuring component 123 and the third pressure measuring component 143 are observed to be normal, the exhaust valve 144 is opened, and the exhaust valve 146 is opened to purge and replace the air in the sample chamber 10.

[0124] 5. Test condition control: Close the drain valve 146, supply power to the cold water supply unit 106, provide cooling capacity to the pre-cooling unit 105 and the cooling unit 141, the pre-cooling unit 105 liquefies the gaseous carbon dioxide into liquid carbon dioxide, and the cooling unit 141 reduces the temperature of the carbon dioxide in the pipeline. Power on each electric heating unit, and each temperature control unit automatically adjusts the power of the electric heating unit according to the preset temperature. Turn on the booster pump 121, and adjust the handles of the pressure regulating valve 80 and the auxiliary pressure regulating valve 91 until the pressure in the sample chamber 10 reaches the preset test pressure and the pressure in the pressure-stabilizing container 92 reaches the preset pressure.

[0125] 6. Adjust the rotation speed: Start the driving member 67, adjust the rotation speed of the driving member 67 according to different linear speed requirements, and start the test.

[0126] 7. After the test, close the drive member 67, the air source valve 102 and the booster pump 121, and slowly rotate the handle of the pressure regulating valve 80 and the handle of the auxiliary pressure regulating valve 91 counterclockwise to reduce the CO in the test system. 2The pressure is discharged to the atmosphere through the pressure regulating valve 80 and the auxiliary pressure regulating valve 91. When the pressures measured by the first pressure measuring element 104, the second pressure measuring element 123 and the third pressure measuring element 143 are all reduced to 0, the cold water supply element 106 and the electric heating elements are turned off. When the temperature of the sample chamber 10 is reduced to room temperature, the fixing element 72 is screwed, the cover 71 is opened, and the sample 50 is taken out.

[0127] Regarding the embodiments of the present application, it should also be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other to obtain new embodiments.

[0128] The above are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. The protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A supercritical CO2 corrosion test system, characterized in that: include: A sample loading device, the sample loading device is configured to have a sample chamber for arranging a sample, the sample chamber is also used to receive a supercritical CO2 fluid, so that the sample in the sample chamber is subjected to a corrosion test under a supercritical CO2 atmosphere; a pressure regulating valve, disposed downstream of the sample chamber along the flow direction of the supercritical CO2 fluid, for regulating the pressure of the sample chamber so that the sample in the sample chamber is tested at a first preset pressure; The auxiliary pressure regulating member is used to increase the pressure at the outlet of the pressure regulating valve.

2. The system according to claim 1, characterized in that The auxiliary pressure regulating member comprises: an auxiliary pressure regulating valve, arranged downstream of the pressure regulating valve along the flow direction of the supercritical CO2 fluid, the supercritical CO2 fluid from the outlet of the pressure regulating valve flows to the inlet of the auxiliary pressure regulating valve, and flows from the outlet of the auxiliary pressure regulating valve to the atmosphere; The auxiliary pressure regulating valve is configured to regulate the pressure on one side of the inlet of the auxiliary pressure regulating valve to a second preset pressure, which is less than the first preset pressure and greater than atmospheric pressure.

3. The system according to claim 2, characterized in that The auxiliary pressure regulating member also includes: A pressure-stabilizing container is provided on a flow path between the pressure regulating valve and the auxiliary pressure regulating valve, and the auxiliary pressure regulating valve regulates the pressure in the pressure-stabilizing container.

4. The system according to claim 3, characterized in that The auxiliary pressure regulating member also includes: A pressure measuring device is arranged on the flow path between the pressure-stabilizing container and the auxiliary pressure regulating valve, and is used to measure the pressure at the inlet of the auxiliary pressure regulating valve so as to adjust the opening of the auxiliary pressure regulating valve according to the pressure measured by the pressure measuring device.

5. The system according to claim 2, characterized in that The auxiliary pressure regulating member also includes: An auxiliary temperature measuring member, used for measuring the temperature of the auxiliary pressure regulating valve; An auxiliary electric heating element heats the auxiliary pressure regulating valve according to the temperature measured by the auxiliary temperature measuring element, so as to heat the temperature of the auxiliary pressure regulating valve to a preset temperature.

6. The system according to claim 5, characterized in that The preset temperature is higher than room temperature, and the second preset pressure is greater than the saturated vapor pressure of CO 2 at room temperature.

7. The system according to claim 2, characterized in that Also includes: a first temperature measuring member, used for measuring the temperature of the pressure regulating valve; A first electric heating element is used to heat the pressure regulating valve according to the temperature measured by the first temperature measuring element, so as to heat the temperature of the pressure regulating valve to a preset temperature.

8. The system according to claim 1, characterized in that The sample loading device comprises: A body having a top opening; A cover body, the cover body is used to close the top opening to form the sample chamber together with the body; A gas inlet interface, used for introducing supercritical CO2 gas into the sample chamber; A gas outlet interface, used to allow the supercritical CO2 gas in the sample chamber to flow out of the sample chamber; A sample holding assembly, disposed in the sample chamber, for holding a plurality of the samples; The rotary driving member is used to drive the sample holding assembly to rotate, so that the supercritical CO2 in the sample chamber can flow along the sample surface at a high speed.

9. The system according to claim 8, characterized in that The sample holding assembly comprises: Two holding members are arranged opposite to each other, each of which is formed with a plurality of positioning grooves, and the samples are disc-shaped samples, and each of the disc-shaped samples is inserted and held in the corresponding positioning grooves of the two holding members; A connecting assembly is used to connect the two retaining members and to connect the two retaining members with the rotating driving member.

10. A supercritical CO2 corrosion test method, characterized in that: The method is implemented using the supercritical CO2 corrosion test system according to any one of claims 1 to 9, and comprises: Supercritical CO2 is introduced into the sample chamber, and the supercritical CO2 flows through the sample chamber, the pressure regulating valve and the auxiliary pressure regulating member in sequence and then enters the atmosphere; adjusting the pressure regulating valve so that the pressure in the sample chamber is a first preset pressure; adjusting the auxiliary pressure regulating member so that the pressure at the outlet of the pressure regulating valve is a second preset pressure, wherein the second preset pressure is less than the first preset pressure and greater than the atmospheric pressure; Afterwards, a supercritical CO2 corrosion test was carried out.

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