An evaluation device and method for an asphaltene dispersant

Abstract

The application discloses an evaluation device and method for asphaltene dispersion inhibitors, and belongs to the technical field of oil and gas field development. The evaluation method of the evaluation device for asphaltene dispersion inhibitors adopts oil samples containing and not containing asphaltene dispersion inhibitors to simulate the pressure reduction process in the crude oil exploitation process, uses a spectrometer to obtain backscattering signals in the two processes, and evaluates the inhibiting effect of the asphaltene dispersion inhibitor based on the changes of the two backscattering signals and time. The asphaltene dispersion inhibitor suitable for high-temperature and high-pressure conditions, with stable performance and inhibiting and dissolving effects on asphaltene precipitation, can be screened out for high-temperature and high-pressure oil wells. Through the evaluation method, technical support is provided for the screening of agents for high-temperature and high-pressure oil wells and the prevention and treatment of asphaltene precipitation, so that the efficient exploitation of high-temperature and high-pressure oil wells is ensured.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas field development technology, and in particular to an evaluation device and method for asphaltene dispersion inhibitors. Background Technology

[0002] With the vigorous exploitation of oil and gas resources, petroleum resources are gradually shifting towards ultra-deep, high-temperature, and high-pressure reservoirs. During the extraction of high-temperature and high-pressure oil wells, the temperature and pressure fluctuations are extremely drastic, leading to severe asphaltenes precipitation and deposition problems. Therefore, research on the prevention and control of asphaltenes precipitation in high-temperature and high-pressure oil wells is of great significance.

[0003] Methods for unclogging oil wells include mechanical scraping, chemical soaking, and physical methods. However, due to the high-temperature and high-pressure operating environment of oil wells, mechanical scraping and physical methods are riskier and more expensive. Therefore, most oilfields still use chemical soaking for unclogging. For high-temperature and high-pressure oil wells, the flash point and boiling point of the chemical agents must be considered to eliminate safety hazards. It is also necessary to avoid altering the chemical properties of the agents due to the high-temperature and high-pressure environment, which could lead to agent failure.

[0004] Therefore, it is urgent to establish a method for evaluating asphaltene precipitation inhibitors suitable for high-temperature and high-pressure oil wells. This evaluation method will provide technical support for the screening of agents and the prevention and control of asphaltene precipitation in high-temperature and high-pressure oil wells, and ensure the efficient exploitation of high-temperature and high-pressure oil wells. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an evaluation device and method for asphaltene dispersion inhibitors.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] An evaluation device for asphaltenes dispersion inhibitors includes a support frame, a light source, a spectrometer, and a processor;

[0008] A reaction vessel is mounted on a support frame, a rotor is installed inside the reaction vessel, and a pressure regulating pump is installed at the bottom of the reaction vessel.

[0009] The reactor is equipped with a viewing window, a thermometer, and a pressure gauge;

[0010] The light source is used to emit visible-near-infrared light into the viewing window;

[0011] The spectrometer is used to receive and record the backscattered light signal scattered by asphalt particles.

[0012] An evaluation method for an asphaltene dispersion inhibitor evaluation device, based on the evaluation device of claim 1, includes the following steps:

[0013] Step 1: Add simulated oil, with or without asphaltene dispersion inhibitors, to the reactor. The temperature, pressure, and gas-oil ratio of the simulated oil in the reactor are determined based on on-site production data from the oilfield.

[0014] Start the rotor, and the rotor in the reactor will stir the simulated oil. Adjust the temperature and pressure until the temperature and pressure data displayed by the thermometer and pressure gauge reach the preset values.

[0015] Step 2: The depressurization process during crude oil extraction is simulated using isothermal depressurization, and the backscattered light signal of the oil sample is recorded over time during the depressurization process.

[0016] Step 3: Add the simulated oil from Step 1, which may or may not contain asphaltenes dispersion inhibitors, into the reactor. The temperature, pressure, and gas-oil ratio of the simulated oil in the reactor are determined based on the field production data of the oilfield.

[0017] The simulated oils in steps 1 and 3 consist of one containing asphaltenes dispersion inhibitor and the other not containing asphaltenes dispersion inhibitor.

[0018] Start the magnetic stirrer. The rotor in the reactor will stir the simulated oil. Adjust the temperature and pressure until the temperature and pressure data displayed by the thermometer and pressure gauge reach the preset values.

[0019] Step 4: Use isothermal depressurization to simulate the depressurization process during crude oil extraction, and record the change of backscattered light signal of oil sample over time during the depressurization process;

[0020] The parameters in step 4 are the same as those in step 2;

[0021] Step 5: Evaluate the performance of asphalt dispersion inhibitors based on changes in backscattered light signal intensity and asphalt precipitation pressure range.

[0022] Furthermore, in steps 2 and 4, the relationship between pressure and time is obtained simultaneously.

[0023] Furthermore, in step 5, the pressure-time relationship in steps 2 and 4 is converted into the backscattered light signal-time relationship to obtain the backscattered light signal-pressure relationship.

[0024] The effect of asphaltene dispersion inhibitors was evaluated based on the changes in backscattered light signal intensity with and without the addition of asphaltene dispersion inhibitors and the pressure range of asphaltene precipitation.

[0025] Furthermore, in steps 2 and 4, the spectrometer recording period is 10 seconds.

[0026] Furthermore, the visible and near-infrared light emitted by the light source has a wavelength of 200–1100 nm.

[0027] Furthermore, the specific operation in step 2 is as follows:

[0028] The light source emits visible and near-infrared light into the viewing window;

[0029] Isothermal depressurization is used to simulate the depressurization process in crude oil extraction. During the isothermal depressurization process, asphaltene particles are precipitated in the crude oil sample due to pressure changes. The precipitated asphaltene particles scatter visible and near-infrared light, generating backscattered light signals.

[0030] The backscattered light signal changes over time throughout the entire process using a spectrometer.

[0031] Furthermore, the intensity of scattered light increases with the increase of the size and concentration of asphalt particles.

[0032] Furthermore, the effectiveness of asphaltene dispersion inhibitors was evaluated based on the asphaltene deposition pressure range and the reduction in backscattered light signal intensity.

[0033] Furthermore, the inhibitory effect of asphaltene dispersion inhibitors was evaluated based on the reduction in the asphaltene deposition pressure range.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] The evaluation device and method for asphaltene dispersion inhibitors of this invention simulates the depressurization process during crude oil extraction using oil samples containing and without asphaltene dispersion inhibitors. Backscattered signals from both processes are acquired using a spectrometer, and the inhibitory effect of the asphaltene dispersion inhibitor is evaluated based on the changes in these two backscattered signals over time. This evaluation method can be used to screen asphaltene dispersion inhibitors in high-temperature, high-pressure reservoirs. By simulating the high-temperature, high-pressure experimental environment of an oil reservoir, it indirectly evaluates the chemical stability and inhibitory effect of asphaltene dispersion inhibitors under high temperature and pressure, thereby screening agents suitable for high-temperature, high-pressure oil wells. Using optical signals as a testing method offers advantages such as high sensitivity and accurate results. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the structure of the evaluation device for the asphaltene dispersion inhibitor of the present invention;

[0037] Figure 2 The change in backscattered light intensity signal with pressure at 130°C, isothermal depressurization, and without the addition of asphaltene dispersion inhibitor in Example 1.

[0038] Figure 3 The change in backscattered light intensity signal with pressure at 130°C, isothermal depressurization, and addition of asphalt dispersion inhibitor in Example 1.

[0039] Figure 4This is a graph showing the backscattered light intensity signal versus pressure at 110°C, isothermal depressurization, and without the addition of asphaltene dispersion inhibitors in Example 2, illustrating the asphaltene deposition status.

[0040] Figure 5 The graph shows the backscattered light intensity signal at 110°C, isothermal depressurization, and the addition of an asphalt dispersion inhibitor as a function of pressure, representing the asphalt deposition status in Example 2. Detailed Implementation

[0041] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0042] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0043] The present invention will now be described in further detail with reference to the accompanying drawings:

[0044] See Figure 1 , Figure 1 An evaluation device for asphaltene dispersion inhibitors according to the present invention includes a support frame, a reaction vessel mounted on the support frame, a rotor inside the reaction vessel, a magnetic stirrer below the reaction vessel, and a constant-speed, constant-pressure pump connected to the bottom of the reaction vessel via valve V4. The experimental pressure of the reaction vessel is obtained by compressing water. A movable piston exists inside the reaction vessel, dividing it into two parts: the upper part, where the crude oil sample and asphaltene dispersion inhibitor are injected during the experiment; and the lower part, where water is pumped in through valve V4 to the bottom of the reaction vessel and the lower part of the piston, to increase the experimental pressure. The experimental pressure is obtained by squeezing the water.

[0045] The light source is transmitted into the sample inside the reactor via an optical fiber perpendicular to the viewing window. When asphaltene particles are present in the sample, the particles scatter light (based on Rayleigh and Mie scattering). By recording the backscattered light signal (parallel to the incident light source direction), the changes in the asphaltene particles can be characterized. A spectrometer is used to receive and record the backscattered light signal.

[0046] An evaluation method for asphaltene dispersion inhibitors, which determines whether the asphaltene dispersion inhibitors are effective against asphaltene particles by the following method:

[0047] Step 1: Prepare simulated oils containing and without asphaltenes dispersion inhibitors;

[0048] In step 1, simulated oil containing or without asphaltene dispersion inhibitors is added to the reactor. The temperature, pressure, and gas-oil ratio of the simulated oil in the reactor are determined based on on-site production data from the oilfield.

[0049] Start the magnetic stirrer. The rotor in the reactor will stir the simulated oil. Adjust the temperature and pressure until the temperature and pressure data displayed by the thermometer and pressure gauge reach the preset values.

[0050] Step 2: Using the isothermal depressurization experimental method, record the change of backscattered light signal over time during the oil sample experiment;

[0051] In step 2, the depressurization process during crude oil extraction is simulated by controlling the pump retraction rate of the constant-speed, constant-pressure pump. The pressure change over time is recorded during the depressurization process. The temperature remains constant during the depressurization process, mainly heated by a copper ring wrapped around the inner wall of the reactor, and measured by a thermometer built into the reactor. The light source emits visible and near-infrared light into the viewing window. During the isothermal depressurization process, the stability of the crude oil system is disrupted due to pressure changes. This disruption causes the components (asphaltite) in the crude oil to precipitate, flocculate, aggregate, and deposit, i.e., the aggregation of asphaltite molecules to form large particles. The precipitated asphaltite particles scatter near-infrared light, and the intensity of the scattered light increases with the size and concentration of the asphaltite particles. The change of the backscattered light signal over time is recorded by a spectrometer, which can characterize the change law of asphaltite particles. By converting the pressure change over time with the backscattered light signal change over time, the relationship between the backscattered light signal and pressure can be obtained. By analyzing the abnormal changes in the backscattered light signal corresponding to the pressure range, the pressure range for asphaltite deposition can be obtained.

[0052] Step 3: Add the simulated oil from Step 1, which may or may not contain asphaltenes dispersion inhibitor, into the reactor. The temperature, pressure, and gas-oil ratio of the simulated oil in the reactor are determined based on the field production data from the oilfield. Step 1 and Step 3 are respectively: one contains asphaltenes dispersion inhibitor and the other does not.

[0053] Start the magnetic stirrer. The rotor in the reactor will stir the simulated oil. Adjust the temperature and pressure until the temperature and pressure data displayed by the thermometer and pressure gauge reach the preset values.

[0054] Step 4: Using the isothermal depressurization experimental method, record the change of backscattered light signal over time during the oil sample experiment; the parameters in Step 4 are consistent with those in Step 2.

[0055] Step 5: Evaluate the performance of asphaltene dispersion inhibitors based on changes in backscattered light signal intensity and asphaltene precipitation pressure range;

[0056] In step 5, the change of backscattered light signal over time is converted into the change of backscattered light signal over pressure; the effect of the asphalt dispersion inhibitor is evaluated by comparing the change of backscattered light signal intensity with and without the addition of asphalt dispersion inhibitor and the pressure range of asphalt precipitation.

[0057] If both the asphaltene deposition pressure range and the backscattered light signal intensity decrease, it indicates that the asphaltene dispersion inhibitor is effective. The effectiveness of the asphaltene dispersion inhibitor can be further compared by the extent to which the asphaltene deposition pressure range is reduced.

[0058] In steps 2 and 4, the spectrometer recording period is 10 seconds, and the selected near-infrared light wavelength is 700 nm.

[0059] Example 1

[0060] The embodiment addresses the frequent problem of asphalt deposition clogging the wellbore during gas injection development, and evaluates the effectiveness of asphalt dispersion inhibitors online. Specifically, it includes the following steps:

[0061] Step 1: Activate the evaluation device for asphaltene dispersion inhibitors.

[0062] like Figure 1 As shown, the evaluation device for the asphaltene dispersion inhibitor of the present invention mainly consists of a high-temperature and high-pressure solid-phase deposition testing device, a backscattering spectrometer, and supporting monitoring software. The high-temperature and high-pressure solid-phase deposition testing device and the backscattering optical device are started, and the relevant equipment parameters of the high-temperature and high-pressure solid-phase deposition testing device and the backscattering optical device are adjusted.

[0063] Step 2: Prepare a high-temperature, high-pressure simulated oil containing asphaltenes dispersion inhibitors.

[0064] Simulated oil containing asphaltenes dispersion inhibitors was added to a reactor. The temperature, pressure, and gas-oil ratio of the simulated oil in the reactor were determined based on field production data from the oilfield. The reservoir temperature was set at 130℃, the reservoir pressure at 90MPa, and the production gas-oil ratio at 400. The temperature was maintained at 130℃. During the isothermal depressurization process, the crude oil sample underwent a pressure change that disrupted the stability of the crude oil system. This disruption caused the components (asphaltenes) in the crude oil to precipitate, flocculate, aggregate, and deposit, i.e., the aggregation of asphaltenes molecules to form large particles. The precipitated asphaltenes particles scatter near-infrared light, and the intensity of the scattered light increases with the size and concentration of the asphaltenes particles. The changes in the backscattered light signal over time were recorded using a spectrometer to characterize the changes in the asphaltenes particles.

[0065] During the test, the spectrometer data recording period was 10 seconds, and the test wavelength was 700 nm.

[0066] Step 3: Prepare a high-temperature, high-pressure simulated oil that does not contain asphaltenes dispersion inhibitors.

[0067] Add simulated oil containing asphaltene dispersion inhibitor to the reactor. The temperature, pressure, and gas-oil ratio of the simulated oil in the reactor are determined based on the field production data of the oilfield. Use the reservoir temperature as the test temperature of 130℃, the reservoir pressure as the initial test pressure of 90MPa, and the production gas-oil ratio as the test gas-oil ratio of 400. Maintain the temperature at 130℃. The parameters in step 3 are consistent with those in step 2.

[0068] Step 4, Evaluation of the effect of asphaltenes dispersion inhibitor

[0069] The inhibitory effect of asphaltene inhibitors before and after addition was characterized by recording changes in backscattered light signal intensity and asphaltene precipitation pressure range.

[0070] See Figure 2 , Figure 2 This is a diagram showing the backscattered light intensity signal versus pressure at 130°C, under isothermal depressurization, and without asphaltene dispersion inhibitors, illustrating asphaltene deposition. (See also:) Figure 3 , Figure 3 The diagram illustrates the backscattered light intensity signal variation with pressure at 130°C, under isothermal decompression, and with the addition of an asphalt dispersion inhibitor, representing the asphalt deposition process. Experiments showed that the light intensity signal variation range of the crude oil sample without the asphalt dispersion inhibitor during isothermal decompression was 150, while that of the crude oil sample with the asphalt dispersion inhibitor was only 80. Furthermore, the asphalt deposition pressure range narrowed from 28-77 MPa without the inhibitor to 29-55 MPa. A larger deposition pressure range indicates a greater asphalt deposition process and a higher deposition risk. Figure 2 and Figure 3 The results showed that the asphaltene deposition pressure range decreased after the addition of the asphaltene inhibitor, indicating that the asphaltene inhibitor suppressed the deposition of some asphaltene particles.

[0071] Example 2

[0072] The same experimental steps as in Example 2 were adopted, but the test conditions were changed to: gas-oil ratio of 400; temperature of 110°C; and reservoir pressure of 90 MPa as the initial test pressure.

[0073] Step 1: Activate the evaluation device for asphaltene dispersion inhibitors.

[0074] like Figure 1 As shown, the evaluation device for the asphaltene dispersion inhibitor of the present invention mainly consists of a high-temperature and high-pressure solid-phase deposition testing device, a backscattering spectrometer, and supporting monitoring software. The high-temperature and high-pressure solid-phase deposition testing device and the backscattering optical device are started, and the relevant equipment parameters of the high-temperature and high-pressure solid-phase deposition testing device and the backscattering optical device are adjusted.

[0075] Step 2: Prepare a high-temperature, high-pressure simulated oil containing asphaltenes dispersion inhibitors.

[0076] Simulated oil containing asphaltenes dispersion inhibitors was added to a reactor. The temperature, pressure, and gas-oil ratio of the simulated oil in the reactor were determined based on field production data from the oilfield. The reservoir temperature was set as the test temperature (110℃), the reservoir pressure as the test pressure (90MPa), and the production gas-oil ratio as the test gas-oil ratio (400). The temperature was maintained at 110℃. During the isothermal depressurization process, the crude oil sample underwent a pressure change, which disrupted the stability of the crude oil system. This disruption caused the components (asphaltenes) in the crude oil to precipitate, flocculate, aggregate, and deposit, i.e., the aggregation of asphaltenes molecules to form large particles. The precipitated asphaltenes particles scatter near-infrared light, and the intensity of the scattered light increases with the size and concentration of the asphaltenes particles. The changes in the backscattered light signal over time were recorded using a spectrometer to characterize the changes in the asphaltenes particles.

[0077] During the test, the spectrometer data recording period was 10 seconds, and the test wavelength was 700 nm.

[0078] Step 3: Prepare a high-temperature, high-pressure simulated oil that does not contain asphaltenes dispersion inhibitors.

[0079] Add simulated oil containing asphaltene dispersion inhibitor to the reactor. The temperature, pressure, and gas-oil ratio of the simulated oil in the reactor are determined based on the field production data of the oilfield. Use the reservoir temperature as the test temperature of 110℃, the reservoir pressure as the test pressure of 90MPa, and the production gas-oil ratio as the test gas-oil ratio of 400. Maintain the temperature at 110℃. The parameters in step 3 are consistent with those in step 2.

[0080] Step 4, Evaluation of the effect of asphaltenes dispersion inhibitor

[0081] The inhibitory effect of asphaltene inhibitors before and after addition was characterized by recording changes in backscattered light signal intensity and asphaltene precipitation pressure range.

[0082] See Figure 4 , Figure 4 This is a graph showing the backscattered light intensity signal versus pressure at 110°C, under isothermal depressurization, and without the addition of asphaltenes dispersion inhibitors, representing the asphaltenes deposition status in Example 2; see [link to example]. Figure 5 , Figure 5 The graph shows the backscattered light intensity signal at 110°C, isothermal depressurization, and the addition of an asphalt dispersion inhibitor as a function of pressure, representing the asphalt deposition status in Example 2.

[0083] pass Figure 4 , Figure 5 The comparison shows that: (1) Asphalt inhibitors can effectively shorten the asphalt precipitation pressure range. After adding the inhibitor, the asphalt deposition range was shortened from 25-83 MPa to 29-58 MPa; (2) Asphalt inhibitors can inhibit asphalt precipitation. The amount of asphalt precipitation is directly proportional to the change in backscattered light signal intensity. After adding the inhibitor, the backscattered light signal intensity difference decreased from 115 to 53.

[0084] An evaluation method for asphaltene dispersion inhibitors is proposed. The working principle is as follows: During the temperature and pressure reduction process, the stability of the crude oil system is disrupted, leading to the precipitation, flocculation, aggregation, and deposition of asphaltene. The precipitated and aggregated asphaltene particles scatter near-infrared light, and the intensity of the scattered light is positively correlated with the size and number of asphaltene particles. Simultaneously, it can shorten the asphaltene deposition pressure range. Therefore, by testing the deposition pressure range and backscattered light signal intensity before and after the addition of the asphaltene dispersion inhibitor, the effect of the asphaltene dispersion inhibitor can be evaluated. The effectiveness of the asphaltene dispersion inhibitor is evaluated by comparing the size of the asphaltene deposition pressure range and the backscattered light signal intensity before and after the addition of the asphaltene dispersion inhibitor.

[0085] An evaluation device and method for asphaltene dispersion inhibitors are disclosed. By testing the effectiveness of asphaltene dispersion inhibitors under high temperature and high pressure conditions, this method screens asphaltene dispersion inhibitors with good dispersion inhibition effects and stable chemical properties to address the problem of asphaltene precipitation and blockage in high-temperature and high-pressure oil wells. This allows for the selection of asphaltene dispersion inhibitors suitable for high-temperature and high-pressure conditions, with stable chemical properties and both inhibitory and dissolving effects on asphaltene precipitation. This evaluation method provides technical support for the screening of reagents and the prevention and control of asphaltene precipitation in high-temperature and high-pressure oil wells, ensuring efficient production from these wells.

[0086] For high-temperature and high-pressure oil wells, the flash point and boiling point of the chemical agents need to be considered when adding them to eliminate potential safety hazards. At the same time, it is also necessary to avoid the chemical properties of the agents changing due to the high-temperature and high-pressure oil well environment, which could lead to agent failure.

[0087] Therefore, there is an urgent need to establish a method for evaluating asphaltene precipitation inhibitors suitable for high-temperature and high-pressure oil wells. This evaluation method will provide technical support for the screening of agents and the prevention of asphaltene precipitation in high-temperature and high-pressure oil wells, ensuring efficient oil production. The evaluation method for asphaltene dispersion inhibitors of this invention uses oil samples containing and without asphaltene dispersion inhibitors to simulate the depressurization process during crude oil production. Backscattered signals from both processes are acquired using a spectrometer, and the inhibitory effect of the asphaltene dispersion inhibitor is evaluated based on the changes in the two backscattered signals over time. This evaluation method can be used to screen asphaltene dispersion inhibitors in high-temperature and high-pressure reservoirs. By simulating the high-temperature and high-pressure experimental environment of the reservoir, the chemical stability and inhibitory effect of asphaltene dispersion inhibitors under high temperature and high pressure are indirectly evaluated, thereby screening agents suitable for high-temperature and high-pressure oil wells. Using optical signals as a testing method has advantages such as high sensitivity and accurate results.

[0088] The evaluation method for asphaltene dispersion inhibitors of the present invention screens out asphaltene dispersion inhibitors that are suitable for high temperature and high pressure conditions, have safe and stable reagent performance, and have the ability to inhibit and dissolve asphaltene precipitation. This provides technical support for efficient and stable production in high temperature and high pressure oil wells and has broad engineering application value and scientific research value.

[0089] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. An evaluation method for an evaluation device for asphaltene dispersion inhibitors, characterized in that, The evaluation is based on an asphaltene dispersion inhibitor evaluation device, the device comprising: Support frame, light source, spectrometer, and processor; A reaction vessel is mounted on a support frame, a rotor is installed inside the reaction vessel, and a pressure regulating pump is installed at the bottom of the reaction vessel. The reactor is equipped with a viewing window, a thermometer, and a pressure gauge. The light source is used to emit visible-near-infrared light into the viewing window; The spectrometer is used to receive and record the backscattered light signal scattered by asphalt particles; The method includes the following steps: Step 1: Add simulated oil, with or without asphaltene dispersion inhibitors, to the reactor. The temperature, pressure, and gas-oil ratio of the simulated oil in the reactor are determined based on on-site production data from the oilfield. Start the rotor, and the rotor in the reactor will stir the simulated oil. Adjust the temperature and pressure until the temperature and pressure data displayed by the thermometer and pressure gauge reach the preset values. Step 2: The depressurization process during crude oil extraction is simulated using isothermal depressurization, and the backscattered light signal of the oil sample is recorded over time during the depressurization process. Step 3: Add the simulated oil from Step 1, which may or may not contain asphaltenes dispersion inhibitors, into the reactor. The temperature, pressure, and gas-oil ratio of the simulated oil in the reactor are determined based on the field production data of the oilfield. The simulated oils in steps 1 and 3 consist of one containing asphaltenes dispersion inhibitor and the other not containing asphaltenes dispersion inhibitor. Start the magnetic stirrer. The rotor in the reactor will stir the simulated oil. Adjust the temperature and pressure until the temperature and pressure data displayed by the thermometer and pressure gauge reach the preset values. Step 4: Use isothermal depressurization to simulate the depressurization process during crude oil extraction, and record the change of backscattered light signal of oil sample over time during the depressurization process; The parameters in step 4 are the same as those in step 2; Step 5: Evaluate the performance of asphaltene dispersion inhibitors based on changes in backscattered light signal intensity and asphaltene precipitation pressure range; In step 5, the pressure-time relationship in steps 2 and 4 is converted into the backscattered light signal-time relationship to obtain the backscattered light signal-pressure relationship. The effect of asphaltene dispersion inhibitors was evaluated based on the changes in backscattered light signal intensity with and without the addition of asphaltene dispersion inhibitors and the pressure range of asphaltene precipitation. The specific operation in step 2 is as follows: The light source emits visible and near-infrared light into the viewing window; Isothermal depressurization is used to simulate the depressurization process in crude oil extraction. During the isothermal depressurization process, asphaltene particles are precipitated in the crude oil sample due to pressure changes. The precipitated asphaltene particles scatter visible and near-infrared light, generating backscattered light signals. The backscattered light signal changes over time throughout the entire process using a spectrometer; The effectiveness of asphaltene dispersion inhibitors is evaluated based on the asphaltene deposition pressure range and the decrease in backscattered light signal intensity. The inhibitory effect of asphaltene dispersion inhibitors was evaluated based on the reduction in the asphaltene deposition pressure range.

2. The evaluation method of the asphaltene dispersion inhibitor evaluation device according to claim 1, characterized in that, In steps 2 and 4, the relationship between pressure and time is obtained simultaneously.

3. The evaluation method of the asphaltene dispersion inhibitor evaluation device according to claim 1, characterized in that, In steps 2 and 4, the spectrometer recording period is 10 s.

4. The evaluation method of the asphaltene dispersion inhibitor evaluation device according to claim 1, characterized in that, The visible and near-infrared light emitted by the light source has a wavelength of 200~1100 nm.

5. The evaluation method of the asphaltene dispersion inhibitor evaluation device according to claim 4, characterized in that, The intensity of scattered light increases with the increase of the size and concentration of asphalt particles.

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