Apparatus for evaluating asphaltene inhibitor inhibition effect and evaluation test method

Abstract

The present application relates to a kind of asphaltene inhibitor inhibitory effect evaluation device and evaluation experimental method, device includes thermostatic water bath, deposition sheet and differential pressure sensor, thermostatic water bath is provided with asphaltene deposition pipeline, one end of asphaltene deposition pipeline is connected with liquid feeding pump by pipeline;The other end of asphaltene deposition pipeline is connected with liquid recovery device by pipeline;Three-way valve is provided on the pipeline between liquid recovery device and asphaltene deposition pipeline, three-way valve is connected with second nitrogen tank;Deposition sheet is arranged in asphaltene deposition pipeline;Differential pressure sensor is arranged at the two ends of asphaltene deposition pipeline respectively, to measure the pressure difference of the two ends of asphaltene deposition pipeline.The device tests the effectiveness of inhibitor in actual operating environment by simulating different temperature, pressure and fluid conditions, the device can simulate actual operating conditions, assess the effect of inhibitor in reducing sediment generation, accurately assess the performance of inhibitor, provide scientific basis for its application.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum and natural gas, and particularly relates to an evaluation device and an evaluation experimental method for the inhibition effect of an asphaltene inhibitor. Background Art

[0002] Asphaltenes are high-molecular compounds that can cause a range of problems during the refining, transportation, and use of petroleum, impacting production efficiency and equipment safety. Asphaltenes are primarily composed of high-molecular organic matter. Asphaltenes can deposit within oil and gas pipelines, storage tanks, and equipment as a result of temperature fluctuations and fluid flow. This deposition not only causes pipeline blockages but also can affect fluid flow and heat transfer efficiency. Asphaltenes also have high viscosity and density, and their formation is closely related to factors such as crude oil composition, temperature, and pressure. Asphaltene deposition can lead to corrosion and wear of equipment, increasing maintenance costs.

[0003] Asphaltene inhibitors can reduce or prevent asphaltene deposition on pipelines and equipment by modifying asphaltene's phase behavior, lowering its viscosity, or enhancing fluidity. These inhibitors are typically surfactants or polymers. With the continuous advancement of oil recovery technology and the increasing development of low-grade and heavy oil fields, the demand for asphaltene inhibitors has become increasingly important. Effective asphaltene inhibitors can significantly improve oil fluidity, reduce transportation costs and equipment maintenance frequency, thereby improving overall production efficiency. Reducing asphaltene deposition is not only crucial for the safe operation of equipment, but also helps to minimize the environmental impact of the oil and gas industry and reduce resource waste.

[0004] However, currently, there are relatively few evaluation criteria and methods for the effectiveness of asphaltene inhibitors, most of which rely on static testing. Asphaltene formation is dependent on numerous factors, including temperature, pressure, and flow conditions, and these complex reaction mechanisms must be considered during the research and development process. This hinders technical personnel from accurately understanding the performance of asphaltene inhibitors in actual applications. Technicians in related fields lack access to data demonstrating the inhibitory effects of asphaltene inhibitors in actual operation, leading to significant uncertainty in their selection and application. This makes the effectiveness of asphaltene inhibitors difficult to predict and evaluate, hindering the promotion and application of the technology.

[0005] In view of this situation, the present invention provides an evaluation device and an evaluation experimental method for the inhibition effect of an asphaltene inhibitor, which can accurately evaluate the performance of the inhibitor and provide a scientific basis for its application. Summary of the Invention

[0006] Aiming at at least one problem in the prior art, the present application aims to provide an asphaltene inhibitor inhibition effect evaluation device and an evaluation experiment method, which can test the effectiveness of the inhibitor in actual operation environment by simulating different temperature, pressure and fluid conditions, and the dynamic test can reflect the actual application effect more than the static test, the device can simulate the actual operation conditions, evaluate the effect of the inhibitor on reducing sediment generation, and accurately evaluate the performance of the inhibitor to provide a scientific basis for its application.

[0007] To achieve the above object, the present application adopts the following technical solutions:

[0008] An asphaltene inhibitor inhibition effect evaluation device, comprising:

[0009] A constant temperature water bath tank, in which an asphaltene deposition pipeline is arranged, one end of the asphaltene deposition pipeline is connected with a liquid adding pump through a pipeline, the other end of the asphaltene deposition pipeline is connected with a liquid recovery device through a pipeline, a three-way valve is arranged on the pipeline between the liquid recovery device and the asphaltene deposition pipeline, and the three-way valve is connected with a second nitrogen tank;

[0010] A deposition sheet arranged in the asphaltene deposition pipeline;

[0011] Pressure difference sensors arranged at two ends of the asphaltene deposition pipeline respectively to measure the pressure difference between the two ends of the asphaltene deposition pipeline.

[0012] Preferably, the liquid adding pump comprises an oil adding pump and a medicine adding pump connected in parallel.

[0013] Preferably, a mixer is arranged on the pipeline at the output end of the oil adding pump and the medicine adding pump.

[0014] Preferably, a first nitrogen tank is arranged on the pipeline at the liquid inlet end of the mixer.

[0015] Preferably, the pressure difference sensors are connected with a data collector and a data processor in sequence.

[0016] Preferably, the deposition sheet is arranged as two sheets, and the two sheets are parallel to each other.

[0017] Preferably, mesh holes are formed in the two deposition sheets.

[0018] Preferably, one of the two deposition sheets is a fixed sheet, and the other is a rotating sheet which can rotate relative to the fixed sheet.

[0019] An asphaltene inhibitor inhibition effect evaluation experiment method, which is completed based on the asphaltene inhibitor inhibition effect evaluation device according to any one of the above, comprising the following steps:

[0020] injecting crude oil configured with asphaltene inhibitors into a liquid addition pump;

[0021] Turning on the constant temperature water bath and setting the experimental temperature;

[0022] Turning on the second nitrogen tank and adjusting the pressure of the asphaltene deposition pipeline through the second nitrogen tank;

[0023] Injecting the crude oil into the asphaltene deposition pipeline through the liquid addition pump at a set flow rate;

[0024] Recording the pipeline pressure at the inlet and outlet of the asphaltene deposition pipeline at a set interval through the differential pressure sensor within a set experimental time;

[0025] Taking out the deposition sheet and observing the asphaltene deposition condition on the deposition sheet.

[0026] Preferably, the opening and closing degrees of the two deposition sheets are adjusted to adjust the mesh size thereon, and the above steps are repeated to evaluate the asphaltene deposition conditions of the two deposition sheets at different opening and closing degrees.

[0027] The present application has the following advantages due to the above technical solutions:

[0028] 1. The asphaltene inhibitor inhibition effect evaluation device and evaluation experiment method provided by the present application can simulate different temperature, pressure and fluid conditions to test the effectiveness of the inhibitor in actual operation environment. This dynamic test can better reflect the actual application effect than the static test. The device can simulate the actual operation conditions to evaluate the effect of the inhibitor on reducing sediment generation and accurately evaluate the performance of the inhibitor, thereby providing a scientific basis for the application of the inhibitor, and further realizing the reduction of cleaning and maintenance costs of equipment and pipelines and the extension of the service life of the equipment.

[0029] 2. The asphaltene inhibitor inhibition effect evaluation device and evaluation experiment method provided by the present application can adjust the opening and closing degrees of the two deposition sheets to adjust the mesh size thereon and evaluate the inhibition effect of the asphaltene inhibitor at different opening and closing degrees. DETAILED DESCRIPTION

[0030] Figure 1 is a connection schematic diagram of the asphaltene inhibitor inhibition effect evaluation device provided by the first embodiment of the present application.

[0031] Figure 2 is a schematic diagram of the fixed sheet and the rotating sheet in the asphaltene deposition pipeline provided by the first embodiment of the present application.

[0032] Figure 3 is a cross-sectional schematic diagram of the fixed sheet and the rotating sheet completely coinciding provided by the first embodiment of the present application.

[0033] Figure 4is a cross-sectional view of the fixed plate and the rotating plate after the rotating plate rotates 30 degrees according to the embodiment one of the present application.

[0034] Figure 5 is a flow chart of the evaluation experimental method of the asphaltene inhibitor inhibition effect according to the embodiment two of the present application.

[0035] Markings in the drawings:

[0036] 1 is a liquid feeding pump, 2 is a first nitrogen tank, 3 is a constant temperature water bath, 4 is a differential pressure sensor, 5 is an asphaltene deposition pipeline, 6 is a deposition plate, 601 is a fixed plate, 602 is a rotating plate, 603 is a bevel gear, 604 is a knob, 7 is a data collector, 8 is a liquid recovery device, 9 is a second nitrogen tank, 10 is a data processor, 11 is a mixer, and 12 is a three-way valve. DETAILED DESCRIPTION

[0037] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are some embodiments but not all embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0038] In the description of the present application, it should be noted that the terms "upper", "lower", "front", "back" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the system or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. The arrows in the drawings represent the flow direction of the material.

[0039] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "assembly", "arrangement", "connection" should be understood broadly, for example, it can be fixedly connected, or detachably connected, or integrally connected; it can be mechanically connected, or electrically connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0040] The application provides an evaluation device and an evaluation experiment method for asphaltene inhibitor inhibition effect, which test the effectiveness of the inhibitor in actual operation environment by simulating different temperature, pressure and fluid conditions, and the dynamic test can reflect the actual application effect more than the static test, the device can simulate the actual operation conditions, evaluate the effect of the inhibitor on reducing deposit generation, accurately evaluate the performance of the inhibitor, and provide a scientific basis for application.

[0041] In the following, the embodiments of the application are described in detail in combination with the drawings.

[0042] Embodiment 1

[0043] Please refer to Figure 1 The evaluation device for asphaltene inhibitor inhibition effect provided in the embodiment can test the effectiveness of the inhibitor in actual operation environment by simulating different temperature, pressure and fluid conditions, the dynamic test can reflect the actual application effect more than the static test, the device can simulate the actual operation conditions, evaluate the effect of the inhibitor on reducing deposit generation, reduce the cleaning and maintenance cost of equipment and pipelines, and prolong the service life of the equipment.

[0044] The evaluation device comprises a constant-temperature water bath 3, a deposit sheet 6 and a differential pressure sensor 4, the constant-temperature water bath 3 is provided with an asphaltene deposition pipeline 5, one end of the asphaltene deposition pipeline 5 is connected with a liquid feeding pump 1 through a pipeline; the other end of the asphaltene deposition pipeline 5 is connected with a liquid recovery device 8 through a pipeline; a three-way valve 12 is arranged on the pipeline between the liquid recovery device 8 and the asphaltene deposition pipeline, the three-way valve 12 is connected with a second nitrogen tank 9; the deposit sheet 6 is arranged in the asphaltene deposition pipeline 5; the differential pressure sensor 4 is arranged at both ends of the asphaltene deposition pipeline 5, respectively, to measure the differential pressure at both ends of the asphaltene deposition pipeline 5.

[0045] Specifically, the constant-temperature water bath 3 is filled with liquid, the asphaltene deposition pipeline 5 is immersed in the liquid, and the heating temperature of the constant-temperature water bath 3 can be set to simulate different temperatures and the passing condition of the fluid in the asphaltene deposition pipeline 5.

[0046] The length of the asphaltene deposition pipeline 5 in the device can range from 8 m to 30 m, and the inner diameter can range from 1 mm to 5 mm, and the liquid feeding pump 1 can be a screw pump to deliver the liquid at a constant flow rate.

[0047] In the embodiment, the liquid feeding pump 1 comprises an oil feeding pump and a chemical feeding pump connected in parallel, crude oil is added in the oil feeding pump, and the inhibitor is added in the chemical feeding pump, and the two are mixed in a mixer 11 on the pipeline at the output end of the oil feeding pump and the chemical feeding pump during work.

[0048] The pipeline at the liquid inlet end of the mixer 11 is provided with a first nitrogen tank 2, which is connected to the pipeline inlet as a constant-pressure nitrogen source. At the end of the experiment, the first nitrogen tank 2 is opened, and the remaining liquid in the pipeline is gradually discharged from the outlet. Under the condition of constant flow, the nitrogen gas blows the liquid in the capillary tube at a constant flow rate, and the deposited asphaltene cannot be blown out. The mass of the liquid in the liquid recycler 8 is weighed, and the change of the mass of the liquid in the liquid recycler 8 with time is recorded. Since the flow rate is constant, the liquid mass is positively linearly related to time. When the liquid in the deposition section is discharged, the volume of the liquid decreases due to the occupation of a part of the volume by the deposited asphaltene. Under the condition of constant flow rate, the discharged liquid decreases, and therefore the slope of the change of the liquid mass in the liquid recycler 8 with time decreases. Thus, combined with the diameter of the capillary tube and the nitrogen flow rate, the thickness of the asphaltene deposition can be inversely calculated.

[0049] In this embodiment, the differential pressure sensor 4 is sequentially connected with the data collector 7 and the data processor 10. The differential pressure data measured by the differential pressure sensor 4 is transmitted to the data processor 10 for processing through the data collector 7, and the data processor 10 can be a computer.

[0050] Specifically, during the experiment, the differential pressure sensor 4 is a high-precision differential pressure sensor, which continuously measures the pressure drop in the asphaltene deposition pipeline 5. The measurement data is recorded and analyzed in real time by a computer. This real-time monitoring can provide important fluid dynamics data, thereby providing a basis for subsequent evaluation of the performance of the inhibitor. The change of the pressure drop not only reflects the flow characteristics of the fluid in the asphaltene deposition pipeline 5, but also indicates the deposition of the asphaltene. The pipeline is immersed in a water bath to maintain isothermal conditions, and the total flow rate of the pipeline is maintained in a laminar flow state.

[0051] Please refer to Figure 2 In this embodiment, the deposition sheet 6 is provided in two pieces, and the two pieces of deposition sheet 6 are parallel to each other.

[0052] Specifically, the two pieces of deposition sheet are both sapphire deposition sheets. Sapphire has extremely high hardness and can withstand high-pressure and high-temperature environments. At the same time, its corrosion resistance makes it perform well in various fluid media. The diameter of the deposition sheet is 1 mm to 2 mm, and the diameter of the deposition sheet is smaller than the inner diameter of the asphaltene deposition pipeline 5.

[0053] In this embodiment, the two deposition sheets are provided with mesh holes; of the two deposition sheets, one is a fixed sheet 601, and the other is a rotating sheet 602 that can rotate relative to the fixed sheet 601.

[0054] Specifically, the fixed sheet 601 can be fixedly connected with the asphaltene deposition pipeline 5 through a connecting rod; the central axis of the rotating sheet 602 is provided with a shaft hole, and a rotating shaft is arranged in the shaft hole; the rotating shaft is connected with the asphaltene deposition pipeline 5 through a connecting rod; the edge of the rotating sheet 602 is processed with a 45-degree bevel gear, so that the rotating sheet 602 becomes a bevel gear; the top of the rotating sheet 602 is horizontally provided with a bevel gear 603 engaged with the rotating sheet 602; the outside of the asphaltene deposition pipeline 5 is provided with a knob 604, and the knob 604 is connected with the center of the bevel gear 603 through a connecting rod. When it is necessary to adjust the opening degree of the meshes on the two deposition sheets, the knob 604 is rotated, the knob 604 drives the bevel gear 603 to rotate, the bevel gear 603 drives the rotating sheet 602 to rotate, and then the opening degree of the meshes on the rotating sheet 602 and the fixed sheet 601 is adjusted.

[0055] Specifically, two sapphire deposition sheets are used to simulate the surface of the well mouth of the well head, and specific size and shape meshes are designed on the two sapphire deposition sheets; the arrangement and size of the meshes can be designed according to needs to ensure the efficiency and controllability of fluid flow in the asphaltene deposition pipeline 5. The fixed sheet 601 is fixed in the pipeline, so that it can remain stationary during the flow of crude oil; the mesh structure of the fixed sheet 601 can successfully flow the liquid through the pipeline while successfully depositing asphaltene on the fixed sheet 601; the rotating sheet 602 of the other sapphire is rotated through the knob outside the pipeline, which allows the angle of the rotating sheet 602 to be adjusted according to needs; by adjusting the angle of the rotating sheet 602, the degree of coincidence of the meshes of the fixed sheet 601 and the rotating sheet 602 can be changed; when the meshes of the two deposition sheets are staggered, the effective area of fluid flow will decrease, and then the flow rate of the fluid will decrease; on the contrary, when the meshes of the two deposition sheets coincide, the flow area of the fluid increases, and the flow rate increases. This control mechanism can simulate various asphaltene deposition environment conditions. After the experiment is completed, the sapphire deposition sheet 6 is disassembled, and the asphaltene particles deposited on the deposition sheet can be further observed, and the asphaltene deposition rate, deposition amount under the influence of different inhibitors can be further studied, and the basic physical properties of the deposits are analyzed. By measuring the weight change of the asphaltene deposition under controlled experimental conditions, the effectiveness of the inhibitor is evaluated.

[0056] Example 2

[0057] Please refer to Figure 3 The asphaltene inhibitor inhibition effect evaluation experiment method provided in the embodiment is completed by using the asphaltene inhibitor inhibition effect evaluation device in the embodiment 1, and includes the following steps:

[0058] S01, the crude oil configured with the asphaltene inhibitor is injected into the liquid feeding pump 1;

[0059] S02, the constant temperature water bath 3 is started, and the experimental temperature is set;

[0060] S03, open the second nitrogen tank 9, adjust the pressure of the asphaltene deposition pipeline 5 through the second nitrogen tank 9;

[0061] S04, inject crude oil into the asphaltene deposition pipeline 5 at a set flow rate through the liquid feeding pump 1;

[0062] S05, record the pipeline pressure at the inlet and outlet of the asphaltene deposition pipeline 5 at a set interval through the differential pressure sensor 4 within a set experimental time;

[0063] S06, take out the deposition sheet 6 and observe the asphaltene deposition condition on the deposition sheet 6.

[0064] In a specific application, the temperature control range of the constant temperature water bath 3 is room temperature to 170°C, and the temperature control accuracy reaches ±0.1°C; the pressure adjustment range of the asphaltene deposition pipeline 5 is 0 to 80 MPa. The device can simulate different temperature, pressure and fluid conditions to test the effectiveness of the inhibitor in the actual operating environment.

[0065] In the experiment, 500 ml of crude oil and asphaltene inhibitor can be injected into different liquid feeding pumps 1 respectively, and different concentrations of mixed liquid can be prepared by controlling the two liquid feeding pumps 1 and mixed and output in the mixer 11. The experimental temperature is set through the constant temperature water bath 3, and the temperature error is less than 0.5°C; when the device reaches the set pressure and temperature, the crude oil is injected into the asphaltene deposition pipeline 5 at a flow rate of 3 mL / h in a laminar flow state, the flow rate is maintained for 20 hours, and the pipeline pressure at the inlet and outlet of the asphaltene deposition pipeline 5 is measured at every 10s interval, the pressure drop in the asphaltene deposition pipeline 5 is continuously measured through the differential pressure sensor 4, the measurement data is recorded and analyzed in real time through the computer, and the fluid dynamics data is obtained, which provides a basis for subsequent inhibitor performance evaluation; after the experimental time arrives, the deposition sheet 6 is taken out and placed under a microscope to observe the asphaltene deposition condition on the deposition sheet 6.

[0066] In this embodiment, the opening degree of the two deposition sheets is adjusted to adjust the mesh size thereon; the opening degree of the two deposition sheets can be set in each experiment, for example, the opening degree is 0 degree or 30 degrees, and the steps of S01 to S06 are repeated to evaluate the asphaltene deposition condition of the two deposition sheets under different opening degrees.

[0067] After the experiment is completed, the constant pressure nitrogen of the pipeline inlet first nitrogen tank 2 is opened, and the second nitrogen tank 9 is closed, under the action of the constant pressure nitrogen, the remaining liquid in the pipeline is gradually discharged from the outlet to the liquid recycler 8 and weighed.

[0068] The experimental method for evaluating the inhibitory effect of the asphaltene inhibitor of this embodiment can effectively evaluate the effectiveness of the inhibitor by quantitatively measuring the weight change of asphaltene deposition under controlled experimental conditions.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An evaluation device for the inhibition effect of an asphaltene inhibitor, characterized in that: include: a constant temperature water bath, wherein an asphaltene deposition pipeline is provided therein, one end of the asphaltene deposition pipeline being connected to a liquid adding pump via a pipeline; the other end of the asphaltene deposition pipeline being connected to a liquid recovery device via a pipeline; a three-way valve being provided on the pipeline between the liquid recovery device and the asphaltene deposition pipeline, and the three-way valve being connected to a second nitrogen tank; a deposition sheet, disposed in the asphaltene deposition pipeline; differential pressure sensors, respectively disposed at both ends of the asphaltene deposition pipeline, for measuring the differential pressure between the two ends of the asphaltene deposition pipeline; The deposition sheets are provided in two pieces, the two deposition sheets are parallel to each other, and both of the deposition sheets are provided with meshes; one of the two deposition sheets is a fixed sheet, and the other is a rotating sheet that can rotate relative to the fixed sheet; the fixed sheet is fixed in the pipeline, and the mesh structure of the fixed sheet allows the liquid to successfully flow through the pipeline while also successfully depositing asphaltene on the fixed sheet; by adjusting the angle of the rotating sheet, the degree of overlap of the meshes of the fixed sheet and the rotating sheet can be changed.

2. The device for evaluating the inhibitory effect of asphaltene inhibitors according to claim 1, characterized in that: The liquid adding pump comprises a fuel pump and a medicine adding pump connected in parallel.

3. The device for evaluating the inhibitory effect of asphaltene inhibitors according to claim 2, characterized in that: A mixer is provided on the pipelines at the output ends of the refueling pump and the dosing pump.

4. The device for evaluating the inhibitory effect of asphaltene inhibitors according to claim 3, characterized in that: A first nitrogen tank is provided on the pipeline at the liquid inlet end of the mixer.

5. The device for evaluating the inhibitory effect of asphaltene inhibitors according to claim 1, characterized in that: The differential pressure sensor is connected to the data collector and the data processor in sequence.

6. An experimental method for evaluating the inhibitory effect of asphaltene inhibitors, characterized in that: The evaluation device for the inhibition effect of the asphaltene inhibitor according to any one of claims 1 to 5 is completed, comprising the following steps: Inject crude oil containing asphaltene inhibitor into the liquid injection pump; Turn on the constant temperature water bath and set the experimental temperature; Open the second nitrogen tank and adjust the pressure of the asphaltene deposition pipeline through the second nitrogen tank; injecting the crude oil into the asphaltene deposition pipeline at a set flow rate through a liquid addition pump; During the set experimental time and at set intervals, the pipeline pressure at the inlet and outlet of the asphaltene deposition pipeline is recorded each time by a differential pressure sensor; Take out the sedimentation sheet and observe the asphaltene deposition condition on the sedimentation sheet.

7. The experimental method for evaluating the inhibitory effect of asphaltene inhibitors according to claim 6, characterized in that: The opening and closing degrees of the two deposition sheets are adjusted to adjust the mesh size, and the above steps are repeated to evaluate the asphaltene deposition conditions of the two deposition sheets at different opening and closing degrees.

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