Corrosion medium evaluation simulation system and evaluation method for corrosion medium

Abstract

The present invention discloses a corrosion medium evaluation simulation system and a method for evaluating a corrosion medium, which relates to the field of oilfield exploitation. The corrosion medium evaluation simulation system includes a supply device for configuring and supplying a corrosion medium, an experimental pipeline for providing a pipeline environment, a recovery device for recovering the corrosion medium, and a temperature and pressure control device for controlling the temperature and pressure in the experimental pipeline. The experimental pipeline includes an inlet for the corrosion medium to enter and an outlet for the corrosion medium to discharge. The inlet is communicated with the supply device through a first pipeline, and the outlet is communicated with the recovery device through a second pipeline. A coupon fixing structure is arranged on the experimental pipeline. By means of the experimental pipeline in the embodiment of the present invention, the actual situation of the corrosion medium in the pipeline can be simulated, the actual corrosion data of the corrosion medium in the pipeline can be obtained, and then the performance of the corrosion medium can be comprehensively evaluated, so as to improve the accuracy and reference value of the performance evaluation of the corrosion medium.

Description

Technical Field

[0001] The present invention relates to the technical field of oil exploitation, and more specifically, to a corrosion medium evaluation simulation system and a method for evaluating corrosion media. Background Art

[0002] During the oilfield production process, the composition of the produced fluid is relatively complex, especially during the water-bearing development period. In addition to a large amount of dissolved salts dissolved in water, there will also be hydrogen sulfide, carbon dioxide, bacteria, etc. During the gathering and transportation process, due to the tightness problem of the gathering and transportation system, it may lead to an increase in dissolved oxygen in the system and a deterioration in the water compatibility of the system, resulting in scale formation. The above factors will all cause an increase in the corrosivity of the medium in the oilfield gathering and transportation system, and even become an important factor restricting the production safety of the system.

[0003] In order to ensure the production safety of the gathering and transportation system, corrosion inhibitors can be used to alleviate the corrosion problem of the gathering and transportation system. For different gathering and transportation systems, selecting a targeted corrosion inhibitor is a prerequisite for the effectiveness of corrosion inhibition measures. However, the current corrosion medium evaluation system cannot simulate the actual corrosion medium working conditions and cannot screen out the corrosion inhibitor composition that matches different corrosion media. Summary of the Invention

[0004] Embodiments of the present invention provide a corrosion medium evaluation simulation system and a method for evaluating corrosion media, so as to solve the problem that the current corrosion medium evaluation results do not match the corrosion medium working conditions.

[0005] An embodiment of the present invention provides a method for evaluating a corrosion medium, which is applied to the technical field of oil exploitation and includes: providing a first corrosion medium without a corrosion inhibitor, and obtaining corrosion data of the first corrosion medium through an experimental pipeline; providing a second corrosion medium with a corrosion inhibitor, and obtaining corrosion data of the second corrosion medium through the experimental pipeline; comparing the corrosion data of the first corrosion medium with the corrosion data of the second corrosion medium to obtain an evaluation result of the corrosion inhibitor;

[0006] The method for evaluating the corrosion medium is carried out by using a corrosion medium evaluation simulation system. The corrosion medium evaluation simulation system includes: a supply device for configuring and supplying the corrosion medium, an experimental pipeline for providing a pipeline environment, a recovery device for recovering the corrosion medium, and a temperature and pressure control device for controlling the temperature and pressure in the experimental pipeline. The experimental pipeline includes an inlet for the corrosion medium to enter and an outlet for the corrosion medium to be discharged. The inlet is connected to the supply device through a first pipeline, the outlet is connected to the recovery device through a second pipeline, and a coupon fixing structure is provided on the experimental pipeline.

[0007] The supply device includes a liquid-phase corrosion medium supply mechanism, an inhibitor supply mechanism, and a gas-phase corrosion medium supply mechanism. The liquid-phase corrosion medium supply mechanism, the inhibitor supply mechanism, and the gas-phase corrosion medium supply mechanism are all connected to the first pipeline through independently provided pipelines.

[0008] The corrosion medium evaluation simulation system and the evaluation method of the corrosion medium provided by the embodiments of the present invention can simulate the actual conditions of the corrosion medium in the pipeline through the experimental pipeline, obtain the actual corrosion data of the corrosion medium in the pipeline, and then comprehensively evaluate the performance of the corrosion medium, improving the accuracy and referenceability of the corrosion medium performance evaluation.

[0009] Other features and advantages of the present invention will be described in the following specification, and part of them will become obvious from the specification, or will be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures specifically pointed out in the specification and the drawings. Description of the Drawings

[0010] The drawings are used to provide a further understanding of the technical solutions of the present invention, and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solutions of the present invention, and do not constitute a limitation to the technical solutions of the present invention.

[0011] Figure 1 It is an experimental device for inhibitor evaluation in the related art;

[0012] Figure 2 It is a structural diagram of the corrosion medium evaluation simulation system according to the embodiment of the present invention;

[0013] Figure 3 It is a structural diagram of the liquid-phase corrosion medium supply mechanism according to the embodiment of the present invention;

[0014] Figure 4 It is a structural diagram of the inhibitor supply mechanism according to the embodiment of the present invention;

[0015] Figure 5 It is a structural diagram of the gas-phase corrosion medium supply mechanism according to the embodiment of the present invention;

[0016] Figure 6A It is a structural diagram of an experimental pipeline implemented by the present invention;

[0017] Figure 6B It is a structural diagram of the hanging part fixing structure implemented by the present invention;

[0018] Figure 6C It is a structural diagram of another experimental pipeline implemented by the present invention.

[0019] Description of the Reference Numerals

[0020] 10 - Experimental device; 11 - Water tank; 12 - Temperature controller; 121 - Heating rod; 122 - Temperature measuring probe; 123 - Thermometer; 13a - Experimental test cup; 13b - Comparative test cup; 14 - Rotating shaft; 15 - Specimen fixing bracket; 16 - Vent pipe; 100 - Corrosion medium evaluation simulation system; 20 - Supply device; 21 - First pipeline; 22 - Liquid-phase corrosion medium; 221 - First storage tank; 2211 - First feeding pipeline; 2212 - First evacuation pipeline; 2213 - First feeding valve; 2214 - First evacuation valve; 2215 - First drainage pipeline; 2216 - First drainage valve; 222 - First connecting pipeline; 223 - First metering pump supply mechanism; 224 - First valve; 225 - Stirring mechanism; 226 - Deaeration circulation pump; 2261 - First circulation pipeline; 2262 - Second circulation pipeline; 2263 - Circulation control valve; 227 - Dissolved oxygen test electrode; 228 - Nitrogen storage tank; 229 - Nitrogen supply pipeline; 2291 - Nitrogen supply valve; 23 - Corrosion inhibitor supply mechanism; 231 - Second storage tank; 2311 - Second feeding pipeline; 2312 - Third feeding pipeline; 2313 - Second feeding valve; 2314 - Second feeding valve; 232 - Second connecting pipeline; 233 - Second metering pump; 234 - Second valve; 235 - Second stirring mechanism; 24 - Gas-phase corrosion medium supply mechanism; 241 - Gas storage tank; 241a - First gas storage tank; 241b Second gas storage tank; 241c - Third gas storage tank; 242 - Third connecting pipeline; 243 - Third valve; 30 - Experimental pipeline; 31 - Specimen fixing structure; 311 - Opening; 312 - Sealing structure; 313 - Specimen fixing rod; 32 - Straight part; 32a - First straight part; 32b - Second straight part; 321 - First part; 322 - Second part; 323 - Pipe diameter transition zone; 33 - Bent part; 40 - Recovery device; 41 - Second pipeline; 42 - Recovery storage tank; 421 - Second evacuation pipeline; 4211 - Second evacuation valve; 422 - Second drainage pipeline; 4221 - Second drainage valve; 50 - Temperature and pressure control device; 51 - Temperature control mechanism; 52 - Pressure control mechanism; 521 - Pressure gas supply storage tank; 522 - Pressure controller. Detailed implementation manners

[0021] To make the objectives, technical solutions and advantages of the present invention more clear and understandable, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined arbitrarily with each other.

[0022] For different gathering and transportation systems, selecting a targeted corrosion inhibitor is a prerequisite for the effectiveness of corrosion inhibition measures. There are many factors affecting the corrosion inhibition effect. In addition to being related to the corrosive medium of the gathering and transportation system, it is also closely related to the production operation parameters of the gathering and transportation system, such as the flow rate of the corrosive medium, temperature and pressure in the miscible transportation system, etc. Moreover, the fluctuation of the production working condition will impact the formed protective film, and it is also necessary to verify the adaptability of the corrosion inhibitor to the fluctuation of the production working condition. The existing common evaluation methods for corrosion inhibitors are the methods specified in domestic and foreign standards, such as ASTM G170-06(2012), SY / T 5273-2014 and QSH0219-2008.

[0023] Figure 1 is an experimental device for evaluating corrosion inhibitors in related technologies. As Figure 1 shown, the experimental device 10 includes a constant temperature water bath, a test cup, a rotating shaft 14 and a coupon fixing rack 15 arranged on the rotating shaft 14. The constant temperature water bath is used to control the temperature of the experiment. The constant temperature water bath includes a water tank 11, a temperature controller 12, a heating rod 121, a temperature measuring probe 122 and a thermometer 123. The test cup is placed in the constant temperature water bath. The test cup includes an experimental test cup 13a with a corrosion inhibitor added and a comparative test cup 13b without a corrosion inhibitor added. The rotating shaft 14 is inserted into the test cup. The coupons are fixed on the coupon fixing rack 15 and rotate under the drive of the rotating shaft 15. Among them, the experimental test cup 13a also includes a ventilation pipe 16, and air is blown into the experimental test cup 13a through the ventilation pipe 16. During the experiment, the experimental test cup 13a and the comparative test cup 13b are placed in the constant temperature water bath. The temperature of the constant temperature water bath is controlled between 30°C and 50°C. The rotating shaft 14 rotates at 75 r / min - 150 r / min and runs for more than 200 h. Then, the performance of the corrosion inhibitor is evaluated by comparing the mass difference between the coupons in the comparative test cup 13b and the coupons in the experimental test cup 13a. From the experimental device in related technologies, it can be seen that the experimental device in related technologies has the following problems: (1) The operating state of the corrosive medium does not match the actual situation, and it is impossible to simulate the real flow state of the corrosive medium in the pipeline, resulting in the inability to detect the changes in corrosion characteristics under the conditions of the flow rate of the corrosive medium, erosion, etc., and it is impossible to accurately determine the corrosion data under the production working condition; (2) It is impossible to simulate the influence of the stratification and flow state of the corrosive medium on the corrosion characteristics during the miscible transportation process; (3) It is impossible to simulate the influence of valves, pipe diameter changes, etc. in the pipeline on the flow state of the corrosive medium, and it is impossible to obtain the corrosion data of the corrosive medium on pipe fittings such as valves and the possible influence of the turbulent state of the corrosive medium on corrosion after passing through pipe fittings such as valves; (4) It is impossible to simulate the influence of the fluctuation of the corrosive medium content on the integrity of the corrosion product film and the corrosion inhibitor film under the actual working condition of the corrosive medium.

[0024] An embodiment of the present invention provides a corrosion medium evaluation simulation system, which includes a supply device for configuring and supplying a corrosion medium, an experimental pipeline for providing a pipeline environment, a recovery device for recovering the corrosion medium, and a temperature and pressure control device for controlling the temperature and pressure in the experimental pipeline. The experimental pipeline includes an inlet for the corrosion medium to enter and an outlet for the corrosion medium to discharge. The inlet is connected to the supply device through a first pipeline, and the outlet is connected to the recovery device through a second pipeline. A coupon fixing structure is provided on the experimental pipeline.

[0025] The corrosion medium evaluation simulation system provided by the embodiment of the present invention can provide different corrosion media through the supply device, simulate the actual situation of the corrosion medium in the pipeline through the experimental pipeline, obtain the actual corrosion data of the corrosion medium in the pipeline, and then comprehensively evaluate the performance of the corrosion medium, improving the accuracy and referenceability of the corrosion medium performance evaluation.

[0026] The following specifically describes the technical solution of the corrosion medium evaluation simulation system according to the embodiment of the present invention with reference to the accompanying drawings.

[0027] Figure 2 is a structural diagram of the corrosion medium evaluation simulation system according to the embodiment of the present invention. As Figure 2 shown, the corrosion medium evaluation simulation system 100 includes a supply device 20, an experimental pipeline 30, a recovery device 40, and a temperature and pressure control device 50. The experimental pipeline 30 includes an inlet for the corrosion medium to enter and an outlet for the corrosion medium to discharge. The inlet is connected to the supply device 20 through a first pipeline 21, and the outlet is connected to the recovery device 40 through a second pipeline 41. The supply device 20 is used for configuring and supplying the corrosion medium. The recovery device 40 is used for recovering the corrosion medium. The experimental pipeline 30 can provide a pipeline environment for the flow of the corrosion medium, and then obtain the corrosion data of the corrosion medium under approximate actual gathering and transportation pipeline conditions, as well as the corrosion inhibition performance data of the corrosion inhibitor. The temperature and pressure control device 50 is used for controlling the temperature and pressure in the experimental pipeline, and then the temperature and pressure in the experimental pipeline can be made the same as or close to the actual working conditions.

[0028] Figure 3 is a structural diagram of the liquid-phase corrosion medium supply mechanism according to the embodiment of the present invention, Figure 4 is a structural diagram of the corrosion inhibitor supply mechanism according to the embodiment of the present invention, Figure 5 is a structural diagram of the gas-phase corrosion medium supply mechanism according to the embodiment of the present invention. As Figures 2 - 5 shown, the supply device 20 includes a liquid-phase corrosion medium supply mechanism 22, a corrosion inhibitor supply mechanism 23, and a gas-phase corrosion medium supply mechanism 24. The liquid-phase corrosion medium supply mechanism 22, the corrosion inhibitor supply mechanism 23, and the gas-phase corrosion medium supply mechanism 24 are all connected to the first pipeline 21 through pipelines.

[0029] As Figure 3As shown, the liquid-phase corrosion medium supply mechanism 22 includes a first storage tank 221 for containing the liquid-phase corrosion medium and a deoxygenation mechanism connected to the first storage tank through a pipeline. The first storage tank 221 is connected to the first pipeline 21 through a first connecting pipeline 222. The liquid-phase corrosion medium in the first storage tank 221 is pumped into the experimental pipeline through a first metering pump 223 provided on the first pipeline 21, and the flow rate of the corrosion medium in the experimental pipeline is controlled by the first metering pump 223. A first valve 224 is provided on the first connecting pipeline 222, and the first valve 224 is located between the first storage tank 221 and the first metering pump 223. A first feeding pipeline 2211 and a first evacuation pipeline 2212 are provided at the top of the first storage tank 221. A first feeding valve 2213 is provided on the first feeding pipeline 2211, and a first evacuation valve 2214 is provided on the first evacuation pipeline 2212. The liquid-phase corrosion medium is added into the first storage tank 221 through the first feeding pipeline 2211. A first drainage pipeline 2215 is further provided at the bottom of the first storage tank 221, and a first drainage valve 2216 is provided on the first drainage pipeline 2215. The first drainage pipeline and the first evacuation pipeline are connected to communicate the first storage tank with the atmosphere, which is beneficial to draining the corrosion medium completely. A first stirring mechanism 225 is provided in the first storage tank 221, and the first stirring mechanism 225 can accelerate the volatilization of dissolved oxygen and make the liquid-phase corrosion medium more uniform. The deoxygenation mechanism includes a first deoxygenation mechanism, and the first deoxygenation mechanism includes a deoxygenation circulation pump 226 and a dissolved oxygen test electrode 227. The inlet of the deoxygenation circulation pump 226 is connected to the bottom of the first storage tank 221 through a first circulation pipeline 2261, and the outlet of the deoxygenation circulation pump 226 is connected to the side wall of the first storage tank 221 through a second circulation pipeline 2262. The dissolved oxygen test electrode 227 is provided on the first circulation pipeline 2261. A circulation control valve 2263 is provided on the first circulation pipeline 2261, and the circulation control valve 2263 is located between the first storage tank 221 and the dissolved oxygen test electrode 227. In one example, the deoxygenation mechanism may further include a second deoxygenation mechanism. The second deoxygenation mechanism includes a nitrogen storage tank 228. The nitrogen storage tank 228 is connected to the first storage tank 221 through a nitrogen supply pipeline 229 for purging the dissolved oxygen in the liquid-phase corrosion medium and the air in the first storage tank. The replaced oxygen and air can be discharged through the first evacuation pipeline 2212. A nitrogen supply valve 2291 is provided on the nitrogen supply pipeline 229. In this embodiment, the medium sample that the liquid-phase corrosion medium can be configured with can also be an actual sample from an oilfield. The liquid-phase corrosion medium may include, but is not limited to, water, electrolytes, and crude oil. The first metering pump may also be provided on the first connecting pipeline, and the first valve is provided between the first metering pump and the first storage tank.

[0030] As Figure 2 and Figure 4As shown in the figure, the corrosion inhibitor supply mechanism 23 includes a second storage tank 231 for configuring the corrosion inhibitor and a second metering pump 233. The second storage tank 231 is communicated with the first pipeline 21 through a second connecting pipeline 232. The second metering pump 233 is arranged on the second connecting pipeline 232. A second valve 234 is arranged on the second connecting pipeline 232. The second valve 234 is located between the second storage tank 231 and the second metering pump 233. The connection position of the first pipeline 21 and the second connecting pipeline 232 is located between the first metering pump 233 and the experimental pipeline. The second storage tank 231 includes a second feeding pipeline 2311 for adding the corrosion inhibitor and a third feeding pipeline 2312 for adding the dispensing solvent. The second feeding pipeline 2311 and the third feeding pipeline 2312 are arranged on the top of the second storage tank 231. A second feeding valve 2313 is arranged on the second feeding pipeline 2311. A third feeding valve 2314 is arranged on the third feeding pipeline 2312. A second stirring mechanism 235 is arranged on the second storage tank 231. The second stirring mechanism 235 can accelerate the dissolution of the corrosion inhibitor and make the corrosion inhibitor solution more uniform.

[0031] As Figure 2 and Figure 5 shown, the gas-phase corrosion medium supply mechanism 24 includes a gas storage tank 241 and a third valve 243. There are multiple gas storage tanks 241, which may include a first gas storage tank 241a for storing hydrogen sulfide H 2 S, a second gas storage tank 241b for storing carbon dioxide CO 2 , and a third gas storage tank 241c for storing other gases for backup. Multiple gas storage tanks 241 are all communicated with the first pipeline 21 through a third connecting pipeline 242. The third valve 243 is arranged on the third connecting pipeline 242. The connection position of the first pipeline 21 and the third connecting pipeline 242 is located between the connection position of the first pipeline 21 and the second connecting pipeline and the experimental pipeline. The third valve is a control valve, which can control the volume of the gas-phase corrosion medium injected into the first pipeline.

[0032] The supply mechanism of this embodiment can simulate the composition of corrosion media in different oil fields, and can also adjust the content of the corrosion medium during the experiment to simulate the influence of content fluctuations on the corrosion properties of the corrosion medium. The corrosion medium includes the corrosion medium with the added corrosion inhibitor.

[0033] Figure 6A This is a structural diagram of an experimental pipeline according to an embodiment of the present invention. Figure 6B This is a structural diagram of a hanging part fixing structure according to an embodiment of the present invention. As Figure 6A and 6BAs shown, the experimental pipeline 30 provides a pipeline environment for corrosive media, and a coupon fixing structure 31 is provided on the experimental pipeline 30. The experimental pipeline 30 includes a straight portion 32 and a bent portion 33 communicating with the straight portion 32. There are multiple straight portions 32, and adjacent straight portions 32 are connected by the bent portion 33. The multiple straight portions 32 and the bent portion 23 form an unclosed annular structure. Coupon fixing structures 31 are provided on both the straight portion 32 and the bent portion 33, so as to detect the corrosion conditions at different positions inside the pipeline. The coupon fixing structure 31 includes an opening 311 opened on the experimental pipeline 30, a sealing structure 312 provided on the experimental pipeline and sealing the opening, and a coupon fixing rod 313 provided on the sealing structure 312 and extending into the experimental pipeline 31.

[0034] In one example, as Figure 6A shown, in order to simulate the possible influence of the turbulent flow state of the corrosive medium on corrosion after passing through the valve and obtain the corrosion data of the corrosive medium on the valve, the experimental pipeline 31 further includes an experimental valve 34 provided on the straight portion 32, and a coupon fixing structure 31 is provided on at least one side of the two sides of the experimental valve 34. When there are multiple straight portions 32, the experimental valve 34 is provided on at least one of the multiple straight portions 32.

[0035] In one example, in order to simulate the influence of the pipe diameter change of the gathering and transportation system pipeline on the flow state of the corrosive medium and obtain the corrosion parameters of the corrosive medium at the pipe diameter change position, there is also a pipe diameter change area in the experimental pipeline. As Figure 6A shown, the multiple straight portions 32 of the experimental pipeline 30 include a first straight portion 32a and a second straight portion 32b. The pipe diameters of the first straight portion 32a and the second straight portion 32a are different. For example, the pipe diameter of the first straight portion 32a is larger than that of the second straight portion 32b. The first straight portion 32a and the second straight portion 32b are connected by the bent portion 33, and there is a pipe diameter transition area on the bent portion 33. Coupon fixing structures 31 are provided on both the pipe diameter transition area and the positions adjacent to the pipe diameter transition area. Figure 6C This is a structural diagram of another experimental pipeline according to an embodiment of the present invention. As Figure 6C shown, the straight portion of the experimental pipeline includes a first part 321, a second part 322, and a pipe diameter transition area 323 located between the first part 321 and the second part 322. The pipe diameters of the first part 321 and the second part 322 are different. For example, the pipe diameter of the first part 321 is larger than that of the second part 322. Coupon fixing structures 31 are provided on both the pipe diameter transition area 323 and the positions adjacent to the pipe diameter transition area 323.

[0036] As Figure 2As shown, the recovery mechanism 40 is used to recover the corrosive medium, including a recovery storage tank 42. The side wall of the recovery storage tank is connected to the experimental pipeline 30 through a second pipeline 41. The recovery storage tank 42 includes a second evacuation pipeline 421 located at the top of the recovery storage tank 42 and a second drainage pipeline 422 located at the bottom of the recovery storage tank 42. A second evacuation valve 4211 is provided on the second evacuation pipeline 421, and a second drainage valve 4221 is provided on the second drainage pipeline 422.

[0037] As Figure 2 shown, the environmental control mechanism 50 includes a temperature control mechanism 51 and a pressure control mechanism 52. The temperature control mechanism 51 includes a temperature controller, a temperature detector, and a heater. The heater can be a heating wire wound around the outside of the experimental pipeline 30. The temperature detector can be arranged inside the experimental pipeline or on the outer wall of the experimental pipeline. The temperature controller controls the heater to heat the experimental pipeline so that the temperature inside the experimental pipeline reaches the experimental temperature. The pressure control mechanism 52 includes a pressure gas supply storage tank 521 and a pressure controller 522. The pressure gas supply storage tank 521 is connected to the side wall of the recovery storage tank 42 through a fourth connecting pipeline. Nitrogen can be contained in the pressure gas supply storage tank 521. The pressure controller 522 is arranged on the fourth connecting pipeline and is used to control the experimental pressure inside the experimental pipeline. The pressure controller can be a pressure maintaining valve.

[0038] The technical solution of the present invention will be further described below through the working principle of the corrosive medium evaluation simulation system.

[0039] Select the corrosive medium according to the experimental needs. The corrosive medium can be an actual oilfield sample or a configured simulation sample. Add the liquid-phase corrosive medium into the first storage tank. The deoxygenation mechanism removes the dissolved oxygen in the liquid-phase corrosive medium. When the environmental control mechanism controls the temperature and pressure inside the experimental pipeline to reach the experimental conditions, the first metering pump starts to pump the liquid-phase corrosive medium into the experimental pipeline. The gas storage tank injects hydrogen sulfide or carbon dioxide gas into the first pipeline. The liquid-phase corrosive medium and the gas-phase corrosive medium are mixed in the first pipeline to obtain the corrosive medium required for the experiment. The corrosive medium flows in the experimental pipeline and flows into the recovery storage tank through the second pipeline. As Figure 6AAs shown in the figure, coupons are fixed on the coupon fixing structure 31 of the experimental pipeline 30. Among them, the coupons on the first coupon fixing structure 31a can obtain the corrosion data at the pipeline bending part. The second coupon fixing structure 31b and the third coupon fixing structure 31c can obtain the corrosion data of the corrosion medium before and after the experimental valve 34, as well as the corrosion data of the corrosion medium when turbulent flow is formed through the experimental valve 34. The coupons on the fourth coupon fixing structure 31d, the fifth coupon fixing structure 31e and the sixth coupon fixing structure 31f can obtain the corrosion data of the corrosion medium before and after the pipe diameter change. After obtaining one or more of the above corrosion data and replacing the coupons, a certain amount of corrosion inhibitor solution can be pumped into the first pipeline through the second metering pump to obtain the corrosion data at the above experimental positions after adding the corrosion inhibitor, and evaluate the performance of the corrosion inhibitor. During the experiment, the composition of the corrosion medium can also be controlled through a metering pump, the second metering pump and the tenth valve on the gas storage tank to cause fluctuations in the content of the corrosion medium, and obtain the data on the influence of the content fluctuations of the corrosion medium on the integrity of the corrosion product film and the corrosion inhibitor film.

[0040] It can be seen from the working principle of the corrosion medium evaluation simulation system of the present invention that, compared with the experimental devices in the related art, the corrosion medium evaluation simulation system of the present invention can simulate the real flow state of the corrosion medium in the pipeline and obtain the corrosion data under the states such as the flow velocity and scouring of the corrosion medium. The liquid-phase corrosion medium supply mechanism provides water and oil liquid-phase media, and the gas-phase corrosion medium supply mechanism provides gas-phase media, so as to simulate the multiphase transportation process and obtain the data on the influence of the stratification and flow state of the corrosion medium on the corrosion characteristics. The experimental pipeline includes a pipe diameter change area and an experimental valve, so as to simulate the influence of valves, pipe diameter changes, etc. in the pipeline on the flow state of the corrosion medium, and obtain the corrosion data of the corrosion medium on pipe fittings such as valves and the data on the influence of the turbulent flow state of the corrosion medium after passing through pipe fittings such as valves on corrosion. The composition of the corrosion medium is controlled through a metering pump, the second metering pump and the tenth valve on the gas storage tank to simulate the content fluctuations of the corrosion medium under actual working conditions, and obtain the data on the influence of the content fluctuations of the corrosion medium on the integrity of the corrosion product film and the corrosion inhibitor film.

[0041] The corrosion medium evaluation simulation system provided by the embodiment of the present invention can provide different corrosion media through the supply device, simulate the actual conditions of the corrosion medium in the pipeline through the experimental pipeline, obtain the actual corrosion data of the corrosion medium in the pipeline, and then comprehensively evaluate the performance of the corrosion medium, improving the accuracy and referenceability of the corrosion medium performance evaluation.

[0042] The embodiment of the present invention also provides a method for evaluating a corrosion medium, including:

[0043] Provide a first corrosion medium without adding a corrosion inhibitor, and obtain the corrosion data of the first corrosion medium through the experimental pipeline.

[0044] In some embodiments, the method for evaluating the corrosive medium of this embodiment further includes:

[0045] Providing a second corrosive medium added with an inhibitor, and obtaining the corrosion data of the second corrosive medium through an experimental pipeline;

[0046] Comparing the corrosion data of the first corrosive medium with the corrosion data of the second corrosive medium to obtain the evaluation result of the inhibitor.

[0047] Wherein, coupons are fixed in the experimental pipeline, and the corrosion data is the mass difference of the coupons before and after the experiment.

[0048] The method for evaluating the corrosive medium provided by the embodiments of the present invention obtains the corrosion data of the corrosive medium through an experimental pipeline. The corrosion data is closer to the actual working conditions of the corrosive medium. The evaluation results of the corrosive medium (including without adding an inhibitor and adding an inhibitor) are more matched with the actual working conditions of the corrosive medium, thereby improving the accuracy and reliability of the evaluation results of the corrosive medium.

[0049] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by terms such as "upper", "lower", "one side", "the other side", "one end", "the other end", "edge", "opposite", "four corners", "periphery", "the structure of the character 'kou'" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the structure referred to has a specific orientation, is constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0050] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "connection", "direct connection", "indirect connection", "fixed connection", "installation", "assembly" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; the terms "installation", "connection", "fixed connection" can be directly connected, or indirectly connected through an intermediate medium, and can be the internal communication of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0051] Although the disclosed embodiments of the present invention are as above, the content described is only the embodiments adopted for the convenience of understanding the present invention, and is not used to limit the present invention. Any person skilled in the art within the scope of the present invention can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed by the present invention. However, the scope of patent protection of the present invention shall still be defined by the appended claims.

Claims

1. An evaluation method for a corrosive medium, characterized in that, applied in the field of oil extraction technology, including: providing a first corrosive medium without adding an inhibitor, obtaining the corrosion data of the first corrosive medium through an experimental pipeline; providing a second corrosive medium with an inhibitor added, obtaining the corrosion data of the second corrosive medium through the experimental pipeline; comparing the corrosion data of the first corrosive medium with the corrosion data of the second corrosive medium to obtain the evaluation result of the inhibitor; the evaluation method of the corrosive medium is carried out by using a corrosive medium evaluation simulation system, and the corrosive medium evaluation simulation system includes: a supply device for configuring and supplying the corrosive medium, an experimental pipeline for providing a pipeline environment, a recovery device for recovering the corrosive medium, and a temperature and pressure control device for controlling the temperature and pressure in the experimental pipeline. The experimental pipeline includes an inlet for the corrosive medium to enter and an outlet for the corrosive medium to discharge. The inlet is connected to the supply device through a first pipeline, the outlet is connected to the recovery device through a second pipeline, and a coupon fixing structure is provided on the experimental pipeline; the supply device includes a liquid-phase corrosive medium supply mechanism, an inhibitor supply mechanism, and a gas-phase corrosive medium supply mechanism. The liquid-phase corrosive medium supply mechanism, the inhibitor supply mechanism, and the gas-phase corrosive medium supply mechanism are all connected to the first pipeline through independently provided pipelines.

2. The evaluation method for a corrosive medium according to claim 1, characterized in that: the liquid-phase corrosive medium supply mechanism includes a first storage tank for storing the liquid-phase corrosive medium, a deoxidation mechanism connected to the first storage tank through a pipeline, and a first metering pump. The first storage tank is connected to the first pipeline through a first connecting pipeline. The first metering pump is arranged on the first pipeline or the first connecting pipeline. A first valve is arranged on the first pipeline or the first connecting pipeline, and the first valve is located between the first metering pump and the first storage tank.

3. The evaluation method for a corrosive medium according to claim 1, characterized in that: the inhibitor supply mechanism includes a second storage tank for configuring the inhibitor and a second metering pump. The second storage tank is connected to the first pipeline through a second connecting pipeline. The second metering pump is arranged on the second connecting pipeline. A second valve is arranged on the second connecting pipeline, and the second valve is located between the second storage tank and the second metering pump.

4. The evaluation method for a corrosive medium according to claim 1, characterized in that: the gas-phase corrosive medium supply mechanism includes a plurality of gas storage tanks and a third valve. The plurality of gas storage tanks are connected to the first pipeline through a third connecting pipeline. The third valve is arranged on the third connecting pipeline.

5. The evaluation method for a corrosive medium according to any one of claims 1-4, characterized in that: the experimental pipeline includes a straight part and a bent part connected to the straight part, and coupon fixing structures are provided on both the straight part and the bent part.

6. The evaluation method for a corrosive medium according to claim 5, characterized in that: there are a plurality of straight parts, a bent part is arranged between adjacent straight parts, and the plurality of straight parts and the bent parts form an unclosed annular structure.

7. The evaluation method of corrosive medium according to claim 6, characterized in that: Among the multiple straight portions, there are adjacent first and second straight portions. The pipe diameters of the first and second straight portions are different. There is a pipe diameter transition zone on the bent portion connecting the first and second straight portions, and coupon fixing structures are provided at both the pipe diameter transition zone and the positions adjacent to the pipe diameter transition zone.

8. The evaluation method of corrosive medium according to claim 6, characterized in that: At least one of the multiple straight portions includes a first part, a second part, and a pipe diameter transition zone located between the first part and the second part. The pipe diameters of the first part and the second part are different, and coupon fixing structures are provided at both the pipe diameter transition zone and the positions adjacent to the pipe diameter transition zone.

9. The evaluation method of corrosive medium according to claim 5, characterized in that: The experimental pipeline further includes experimental valves provided on the straight portions. Coupon fixing structures are provided on both sides of the experimental valves to simulate the influence of the turbulent flow state on corrosion after the corrosive medium passes through the experimental valves, and to obtain the corrosion data of the corrosive medium on the experimental valves.

10. The evaluation method of corrosive medium according to claim 1, characterized in that: Coupons are fixed in the experimental pipeline, and the corrosion data is the mass difference of the coupons before and after the experiment.

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