A device and experimental method for determining the stability of emulsion

Abstract

The application discloses a device for measuring emulsion milk strong stability, and belongs to the field of oil field acidification backflow detection, wherein the device comprises a centrifuge and a computer connected with the centrifuge, a centrifugal test tube rack is internally arranged in the centrifuge, a plurality of special test tubes are arranged on the centrifugal test tube rack, the special test tubes are connected with the centrifugal test tube rack through a vertical rotating structure, and a magnetic attraction transmission structure for magnetic attraction fixing and data transmission is arranged on the special test tubes; the special test tube comprises a test tube body, a light source for emitting light rays, a light intensity sensor for receiving light intensity data of the light rays penetrating through the emulsion, and a gray scale sensor for receiving gray scale data of the emulsion after being irradiated by the light rays are arranged in the test tube body. The special test tube with the light intensity and gray scale data acquisition function is matched with the centrifuge, simple, fast and efficient emulsion milk strong stability detection is realized, the acidification backflow detection technology is improved, and theoretical support is provided for continuous development of subsequent acidification backflow reuse research.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oilfield acidizing backflow detection, in particular to a device and experimental method for measuring emulsion stability. BACKGROUND

[0002] In the long-term water injection development process of oil reservoirs, scaling in the near-well formation can cause the injection capacity of the injection well to decline, which directly leads to a significant decline in the injection capacity of the injection well. This scaling phenomenon not only limits the water injection efficiency, but also increases the operating cost, posing a serious challenge to the sustainable and efficient development of oilfields. In response to this problem, acidizing technology has emerged and quickly become an important part of oilfield stimulation measures.

[0003] For oil wells, acidizing can significantly enhance the permeability of the near-well zone, allowing crude oil to flow more smoothly to the wellbore, thereby increasing the liquid production of the oil well. For injection wells, acidizing can remove the plugging caused by scaling, ensuring that water or polymer injection media can enter the formation smoothly, maintaining or improving water injection efficiency.

[0004] However, oil well acidizing also brings a series of new problems, the most prominent of which is the emulsification phenomenon caused by the mixing of crude oil and backflow fluid. This emulsion not only has strong stability and is difficult to break by conventional methods, but also has a high content of crude oil in the emulsion, which seriously affects the treatment efficiency and cost of acidizing backflow fluid. More seriously, if the crude oil in the emulsion cannot be effectively recovered, it will cause great waste of resources and environmental pollution.

[0005] Currently, there is no in-depth research on the emulsification mechanism of crude oil in acidizing backflow fluid. Unlike the emulsification mechanism of conventional crude oil, the emulsification mechanism of acidizing crude oil is more complex, so conventional treatment methods are difficult to meet the requirements, and the emulsification of crude oil in acidizing backflow fluid will seriously affect the treatment of acidizing backflow fluid. This not only helps to improve the effectiveness and efficiency of acidizing operations, but also promotes the sustainable development and environmental protection of oilfields. At the same time, it also has important significance for promoting the technological progress in the fields of oilfield chemistry and petroleum engineering. SUMMARY

[0006] The purpose of the present application is to provide a device and experimental method for measuring emulsion stability, which realizes data collection, transmission and processing analysis by using a specially designed test tube with light intensity and gray scale data collection function in cooperation with a centrifuge, realizes simple, fast and efficient emulsion stability detection, perfects the acidizing backflow detection technology, and provides theoretical support for the continuous development of subsequent acidizing backflow reuse research.

[0007] In order to achieve the above object, the application provides a device for measuring the stability of emulsion, which comprises a centrifuge and a computer connected with the centrifuge, a centrifugal test tube rack is installed in the centrifuge, a plurality of special test tubes are arranged on the centrifugal test tube rack, the special test tubes are connected with the centrifugal test tube rack through a vertical rotation structure, and a magnetic attraction transmission structure for magnetic attraction fixing and data transmission is arranged on the special test tubes; the special test tube comprises a test tube body, a light source for emitting light is arranged in the test tube body, a light intensity sensor for receiving light intensity data of the light transmitted through the emulsion is arranged in the test tube body, and a gray scale sensor for receiving gray scale data of the emulsion after being irradiated by the light is arranged in the test tube body.

[0008] Preferably, the vertical rotation structure comprises a plurality of fixing pieces for fixing the special test tubes, and the two ends of the fixing pieces are rotationally connected with the centrifugal test tube rack.

[0009] Preferably, an opening for accommodating the special test tubes after vertical rotation is arranged on the centrifugal test tube rack.

[0010] Preferably, the magnetic attraction transmission structure comprises a magnetic attraction protrusion arranged on the special test tube, a magnetic attraction groove matched with the magnetic attraction protrusion is arranged on the fixing piece, and metal contacts for data transmission are arranged on the magnetic attraction protrusion and the magnetic attraction groove.

[0011] Preferably, the magnetic attraction transmission structure realizes power supply and data transmission through a slip ring structure.

[0012] Preferably, the light source is arranged at the center of the test tube body.

[0013] Preferably, the light intensity sensor and the gray scale sensor are arranged on the inner wall of the test tube in a circumferential uniform manner.

[0014] The application provides an experimental method for measuring the stability of emulsion, which comprises the following steps:

[0015] Step one, taking the emulsion in a natural state, an equal amount of the emulsion is poured into the special test tube;

[0016] Step two, the special test tube is inserted into the centrifugal test tube rack of the centrifuge and is magnetically fixed;

[0017] Step three, the computer is started, an initial image is analyzed and recorded, and the light intensity of the light source in the test tube is adjusted through the computer control;

[0018] Step four, the centrifuge is started, and an initial rotation test is performed;

[0019] Step five, after preparation, the centrifuge is fully started, the rotation speed is set, and a test for a specified time is performed;

[0020] Step six, the light intensity sensor and the gray level sensor respectively collect light intensity data and gray level data and transmit them to the computer in real time, the computer makes a decision and displays the image, records the final result and time of the emulsion layering, and analyzes the change rule of the image;

[0021] Step seven, when the display result of the computer no longer changes or reaches the predetermined time, the centrifuge is turned off.

[0022] Therefore, the device and the experimental method for measuring the emulsion stability have the following beneficial effects:

[0023] 1. The emulsion stability detection method is simple, can process the stability of the emulsion at each moment, the separation rate and the separation time of the emulsion, obtain various properties related to the stability of the test emulsion, can monitor and make decisions at any time, digitize the whole process of the emulsion change, and is helpful to improve the effect and efficiency of acidizing operation, promote the sustainable development of oil fields and environmental protection.

[0024] 2. The special test tube in the application collects light intensity and gray level data during centrifugation, cooperates with the convex points and grooves of the magnetic data transmission, improves the convenience of detection, avoids improper operation and operation differences of the experimenters, and realizes simple, fast and efficient emulsion stability detection.

[0025] 3. The emulsion stability is detected and analyzed by the application, various analysis pictures are obtained, the characteristic changes in the emulsion layering process are analyzed, and the emulsion stability is analyzed, so that subsequent research can be carried out, and the flowback fluid can be reused.

[0026] 4. The test method and equipment provided by the application analyze the change trend of the stability of various types and compositions of emulsions, analyze their own characteristics, evaluate the effect, and provide theoretical support for the continuous development of subsequent acidizing flowback fluid reuse research.

[0027] The technical solutions of the application will be further described in detail below with reference to the drawings and examples. DESCRIPTION OF DRAWINGS

[0028] Figure 1 The device structure diagram for measuring the emulsion stability of the embodiment of the application is shown in the figure;

[0029] Figure 2 The front view of the centrifugal test tube rack of the embodiment of the application is shown in the figure;

[0030] Figure 3 The top view of the centrifugal test tube rack of the embodiment of the application is shown in the figure;

[0031] Figure 4A schematic diagram of the special-purpose centrifuge tube rotating vertically in the embodiment of the present application;

[0032] Figure 5 A schematic diagram of the internal structure of the special-purpose centrifuge tube in the embodiment of the present application;

[0033] Figure 6 A top view of the special-purpose centrifuge tube in the embodiment of the present application.

[0034] Reference numerals

[0035] 1, special-purpose centrifuge tube; 2, centrifuge tube body; 3, light source; 4, magnetic attraction protrusion; 5, centrifuge tube rack; 6, magnetic attraction groove; 7, slip ring structure; 8, opening; 9, fixing piece; 10, centrifuge; 11, light intensity sensor; 12, gray scale sensor. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical scheme and advantages of the embodiment of the present application more clear, the embodiment of the present application is further described in detail below in combination with the drawings and the embodiment. It should be understood that the specific embodiments described herein are only used to explain the embodiment of the present application, and are not used to limit the embodiment of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application. The examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout.

[0037] It should be noted that the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or server comprising a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0038] Similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0039] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the indicated device or element 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.

[0040] In the description of the present application, it is also necessary to explain that, unless otherwise explicitly specified and limited, the terms "arrangement", "installation", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0041] Embodiment

[0042] As shown in Figure 1 , Figure 2 , the device for measuring the emulsion stability of the emulsion of the present application comprises a centrifuge 10 and a computer connected with the centrifuge 10. The centrifuge 10 adopts a TDZ5-WS / TDZ5WS type centrifuge 10. A centrifuge test tube rack 5 is installed inside the centrifuge 10, and a plurality of special test tubes 1 are arranged on the centrifuge test tube rack 5.

[0043] As shown in Figure 5 , Figure 6 , the special test tube 1 comprises a test tube body 2, a light source 3 for emitting light is arranged inside the test tube body 2, a light intensity sensor 11 for receiving the light intensity data of the light transmitted through the emulsion, and a gray scale sensor 12 for receiving the gray scale data of the emulsion after being irradiated by the light. The test tube body 2 is a specially designed functional test tube, which is made of stainless steel material to avoid reaction with residual acid in the acidified flowback fluid and other chemical agents. The light source 3 is arranged at the center inside the test tube body 2, and the light source 3 adopts a laser light source which can adjust the light intensity. The light intensity sensor 11 and the gray scale sensor 12 are arranged uniformly on the inner wall of the test tube according to the circumference, wherein the light intensity sensor 11 and the gray scale sensor 12 are arranged at intervals, there is one gray scale sensor 12 between the adjacent two light intensity sensors 11, and there is one light intensity sensor 11 between the adjacent two gray scale sensors 12. By changing different light intensities, the visual effect is optimized, and the imaging is more clear and accurate.

[0044] As shown in Figure 2 , Figure 3 , Figure 4 , the special test tube 1 is connected with the centrifuge test tube rack 5 through a vertical rotation structure. The vertical rotation structure comprises a plurality of fixing pieces 9 for fixing the special test tube 1, and the two ends of the fixing piece 9 are rotationally connected with the centrifuge test tube rack 5. An opening 8 for accommodating the special test tube 1 after vertical rotation is arranged on the centrifuge test tube rack 5. The centrifuge test tube rack 5 is fixed on the rotating disc of the centrifuge 10, and the fixing piece 9 on the centrifuge test tube rack 5 can rotate in the vertical direction of the rotating disc of the centrifuge 10, and when the rotating speed is high, it can present an almost horizontal state, and the special centrifuge test tube can be fixed on the fixing piece 9 and rotate with it.

[0045] The special test tube 1 is provided with a magnetic attraction transmission structure for magnetic attraction fixing and data transmission. The magnetic attraction transmission structure comprises magnetic attraction protrusions 4 provided on the special test tube 1, and the fixing member 9 is provided with magnetic attraction grooves 6 matched with the magnetic attraction protrusions 4. The magnetic attraction protrusions 4 and the magnetic attraction grooves 6 are provided with metal contacts for data transmission. The magnetic attraction transmission structure realizes power supply and data transmission through the existing slip ring structure 7.

[0046] The experimental method for measuring the emulsion stability of the emulsion liquid comprises the following steps:

[0047] Step one, take the emulsion liquid in a natural state, and pour an equal amount into the special test tube 1.

[0048] Step two, insert the special test tube 1 into the centrifuge test tube rack 5 of the centrifuge 10, and adjust the test tube so that the magnetic attraction protrusions 4 and the magnetic attraction recesses are attracted and fixed.

[0049] Step three, turn on the computer, analyze the initial image and record, and adjust the light intensity of the light source 3 in the test tube through the computer control to achieve the best effect.

[0050] Step four, turn on the centrifuge 10, and perform an initial rotation test to avoid jamming or shaking.

[0051] Step five, after everything is ready without any unexpected situation, fully open the centrifuge 10, set the rotation speed, and perform a test for a specified time.

[0052] Step six, the light intensity sensor 11 and the gray scale sensor 12 respectively collect light intensity data and gray scale data and transmit them to the computer in real time, the computer makes decision and displays the image, records the final result and time of the emulsion liquid layering, and analyzes the change rule of the image.

[0053] The light intensity sensor 11 can receive light transmitted through the emulsion liquid, and the gray scale sensor 12 can receive gray scale data transmitted through the emulsion liquid, which are transmitted to the centrifuge 10 through the magnetic attraction protrusions 4, the magnetic attraction grooves 6 and the slip ring structure 7. The centrifuge 10 transmits the data to the computer through the transmission line. The computer quantifies the collected data to obtain the corresponding quantitative stability value, processes the quantitative relationship between the gray scale and the stability to obtain the corresponding quantitative stability value, and judges the corresponding position of each phase page after centrifugal layering. The computer generates two images through light intensity data collection and gray scale data collection to form a contrast, which can avoid errors caused by internal impurities, light factors and other factors.

[0054] Step seven, when the display result of the computer no longer changes or reaches a predetermined time, the centrifuge 10 can be turned off.

[0055] The present application can realize emulsion stability detection and analysis, including but not limited to the determination of the characteristics of acidified reverse fluid emulsion. For different emulsions or acid return fluids, the method is consistent, and the above steps are repeated by replacing the test tube.

[0056] The emulsion stability quantification method adopts an ultrasonic wave-promoted emulsion gray value quantification method to convert the received light intensity into a gray image, and processes the corresponding method according to the research.

[0057] The quantification method is briefly introduced as follows:

[0058] According to the captured emulsion image, the oil-water emulsification characteristics are quantitatively analyzed, all images are arranged, batch processing is performed through image processing software Photoshop, the image gray value near the oil-water interface position is measured with time, and then the oil phase concentration change in the emulsion is calculated, and the emulsification speed is analyzed.

[0059] It can be known from the observation of the oil-water emulsification phenomenon at different times under the action of ultrasonic waves that the oil-water two phases will gradually form an emulsion under the action of ultrasonic waves, and the oil phase exists in the form of extremely small droplets in the water phase. The emulsification speed to be measured can be represented by the amount of crude oil emulsified per unit time. The longer the emulsification time, the more oil droplets dispersed in the water phase, and the darker the image color, which indicates that the ultrasonic emulsification method for measuring the emulsification speed is feasible. At the same time, the observation pictures are uniformly converted into gray images, and the emulsification effect is represented by analyzing the gray difference.

[0060] According to the difference relationship between the emulsion speed formed by ultrasonic vibration and the gray scale of the cuvette image, the actual image is converted into a gray image, and the gray scale change rule of the cuvette at different positions and different times is read through image recognition software and Python software.

[0061] After digitizing the pictures according to the above method, the gray scale curves at different times and different positions are drawn, and the relationship curve between the crude oil concentration after ultrasonic emulsification and the gray value is obtained by using the standard curve of absorbance obtained by spectrophotometry under different oil contents, as shown in Figure 2 .

[0062] In order to make the results more convincing, the centrifugal principle of the centrifuge 10 is used to prove it.

[0063] When an object moves in a circular motion around a central axis, a force pointing outward from the circle will be generated, which is the centrifugal force. In the centrifuge 10, the special test tube 1 containing the sample is placed on the high-speed rotating turntable. As the rotation speed increases, the components in the sample are subjected to different degrees of centrifugal force due to differences in mass, density or shape.

[0064] The centrifuge 10 utilizes the centrifugal force generated by high-speed rotation to separate different components in the emulsion according to the differences in density, size or particle shape. Specifically, the centrifugal force makes the particles with larger mass or density receive a greater force, and thus be thrown to the outside of the centrifuge tube; while the particles with smaller mass or density receive a smaller force, and stay at the inside of the centrifuge tube or a position closer to the center. In this way, different emulsion components are stratified under the action of the centrifugal force.

[0065] The size of the relative centrifugal force is related to the rotational radius of the position and the rotation speed of the rotating disc, and its calculation formula is:

[0066]

[0067] Wherein, RCF represents the relative centrifugal force, expressed in multiples of gravitational acceleration (g). R represents the rotational radius, in centimeters (cm). rpm represents the rotation speed, in revolutions per minute. The schematic diagram is shown in Figure 3 .

[0068] The gray scale diagram is obtained after the emulsion is fully separated and stratified by the centrifuge 10, and different depths of color are displayed due to the different light transmittances of different layers of liquid. However, the projected color of the cuvette will change during the emulsification process. In order to avoid experimental errors, the images of different depths of color can be uniformly changed to gray scale diagrams, and the emulsification effect is represented by analyzing the color gray scale difference. The relationship between the centrifugal force, the gray scale value and the oil content of the emulsion according to the data test is shown in Figure 4 .

[0069] From the above figure, it can be seen that the size of the centrifugal force and the measured gray scale value and the stability of the emulsion all have a relatively stable linear relationship, which confirms the rationality of the gray scale value method.

[0070] The parts not involved in the above-mentioned method can be realized by adopting or referring to the existing technology.

[0071] Finally, it should be pointed out that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit it. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can still be modified or replaced by equivalents, and these modifications or replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.​

Claims

1. An experimental method for determining the emulsion strength stability of an emulsion, characterized in that: The device used in this method includes a centrifuge and a computer connected to the centrifuge. The centrifuge is equipped with a centrifuge tube rack, on which several specially designed test tubes are placed. The specially designed test tubes are connected to the centrifuge tube rack through a vertical rotation structure. The specially designed test tubes are equipped with a magnetic attraction transmission structure for magnetic fixation and data transmission. The specially designed test tube includes a test tube body, and inside the test tube body are a light source for emitting light, a light intensity sensor for receiving light intensity data transmitted through the emulsion, and a grayscale sensor for receiving grayscale data of the emulsion after being irradiated by light. The light source is located at the center inside the test tube. Both the light intensity sensor and the grayscale sensor are arranged evenly in a circular pattern on the inner wall of the test tube. The experimental method includes the following steps: Step 1: Take the emulsion in its natural state and pour an equal amount into a special test tube; Step two: Insert the special test tubes into the centrifuge tube rack of the centrifuge and secure them magnetically; Step 3: Turn on the computer, analyze and record the initial images, and adjust the light intensity of the light source in the test tube using computer control. Step 4: Turn on the centrifuge and perform an initial rotation test; Step 5: Once everything is ready, turn the centrifuge on full speed, set the rotation speed, and conduct a test for the specified time. Step six: The light intensity sensor and grayscale sensor collect light intensity data and grayscale data respectively and transmit them to the computer in real time. The computer's decision-making and image display are viewed, the final result and time of emulsion stratification are recorded, and the change pattern of the image is analyzed. Among them, the computer quantizes the collected data to obtain the corresponding quantitative stability value. The quantitative relationship between grayscale and stability is used to process the data and give the corresponding quantitative stability value, and the corresponding position of each phase liquid surface after centrifugation stratification is determined. Step 7: Once the computer display stops changing or the predetermined time has elapsed, turn off the centrifuge.

2. The experimental method for determining the emulsion strength stability of an emulsion according to claim 1, characterized in that: The vertical rotation structure includes several fixing components for fixing specially designed test tubes, with both ends of the fixing components rotatably connected to the centrifuge tube rack.

3. The experimental method for determining the emulsion strength stability of an emulsion according to claim 2, characterized in that: The centrifuge tube rack has an opening for accommodating specially designed test tubes after vertical rotation.

4. The experimental method for determining the emulsion strength stability of an emulsion according to claim 2, characterized in that: The magnetic transmission structure includes a magnetic protrusion on a specially designed test tube, a magnetic groove on a fixing component that matches the magnetic protrusion, and metal contacts for data transmission on the magnetic protrusion and magnetic groove.

5. The experimental method for determining the emulsion strength stability of an emulsion according to claim 4, characterized in that: The magnetic transmission structure achieves power supply and data transmission through a slip ring structure.

Images