Recognition and evaluation method for monitoring demulsification on-line by laser confocal microscope

Abstract

The application discloses a kind of identification and evaluation method for monitoring demulsification on-line by laser confocal microscope, and relates to the identification and evaluation technical field of demulsification process, the method is loaded emulsion by special on-line observation sample cell, and time reference is initialized synchronously by accurately injecting demulsifier by micro-injection pump, Z axis scanning is carried out according to time sequence using laser confocal microscope, and three-dimensional image data stack is obtained by automatically adjusting acquisition frequency.Extracting key kinetic parameters such as droplet coalescence rate and phase separation speed by dynamic three-dimensional reconstruction and quantitative analysis, the objective quantitative evaluation of demulsifier efficiency is realized by combining parameter variation trend, and dynamic three-dimensional rendering video and parameter curve can also be generated.The method has short experimental period and repeatable results, and is suitable for crude oil dehydration, sewage treatment and other fields, to provide scientific data support for demulsifier screening and process optimization.

Description

Technical Field

[0001] This invention relates to the field of identification and evaluation technology of demulsification process, specifically a method for identification and evaluation of demulsification by online monitoring using laser confocal microscopy. Background Technology

[0002] Demulsifiers are key chemical agents used to promote the separation of the oil and water phases in emulsions. They are widely used in petroleum extraction, crude oil dehydration, wastewater treatment, chemical separation, food processing, and cosmetics preparation. Their performance directly affects production efficiency, processing costs, and product quality; therefore, the identification and performance evaluation of demulsifiers have significant research and engineering application value.

[0003] The mainstream method for evaluating demulsifier performance in the industry is still the bottle test method. This method typically involves adding a demulsifier to a certain amount of emulsion, allowing it to stand for a period of time, and then judging the demulsification effect by visually inspecting or reading the volume changes of the upper and lower phases using a graduated cylinder. While the bottle test method is simple to operate, it has significant drawbacks:

[0004] It can only obtain static results before and after demulsification, and cannot reveal the dynamic behaviors of droplets such as aggregation, flocculation, migration and phase separation during the demulsification process; it relies on manual visual observation of interface changes, and the evaluation results are greatly affected by the operator's experience and environmental factors, resulting in poor repeatability; it usually requires standing for several hours or even days, which is difficult to meet the needs of high-throughput screening and rapid optimization of demulsifiers; it can only provide endpoint indicators such as volume separation rate, and lacks kinetic process data, which is not conducive to revealing the demulsification mechanism.

[0005] With the development of microscopic imaging technology, laser confocal microscopy, due to its high resolution, optical sectioning, and three-dimensional imaging capabilities, has been used for emulsion structure analysis. However, existing research mainly focuses on the morphological observation and interface structure analysis of static emulsion samples, and cannot yet achieve real-time monitoring and quantitative evaluation of the dynamic action of demulsifiers. This is mainly because traditional microscopy systems lack synchronous control with the demulsifier addition process, and also lack suitable sample cells and data processing methods for dynamic observation.

[0006] In addition, other auxiliary detection methods, such as turbidity measurement, interfacial tension testing, conductivity change or particle size analysis, can indirectly reflect the demulsification process, but they are mostly offline sampling and analysis, making it difficult to achieve continuous and real-time process tracking, and they cannot obtain the three-dimensional structural changes of the system.

[0007] Therefore, existing demulsification evaluation technologies generally suffer from insufficient real-time performance, limited quantitative capabilities, and strong subjectivity, failing to comprehensively reveal the mechanism of action and dynamic characteristics of demulsifiers in emulsion systems. The industry urgently needs a new method for evaluating demulsifier performance that enables online monitoring, three-dimensional dynamic imaging, and quantitative analysis, thereby providing scientific and reliable data support for the efficient screening, mechanism research, and industrial optimization of demulsifiers. Summary of the Invention

[0008] The purpose of this invention is to provide a method for online monitoring and evaluation of demulsification using laser confocal microscopy, in order to solve the problems mentioned in the background art.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a method for online monitoring, identification, and evaluation of demulsification using laser confocal microscopy, the specific steps of which are as follows:

[0010] S1. Sample Cell Design and Sample Loading

[0011] The emulsion to be tested is injected into a specially designed online observation sample cell. The sample cell has an inlet and an outlet and is equipped with slit flow, dialysis or bilayer structure to ensure that the oil-water interface is always within the microscope observation range during the demulsification process, while allowing the demulsifier to be introduced and mixed in real time.

[0012] S2. Demulsifier introduction and process initialization

[0013] Demulsifier is precisely injected into the middle of the sample cell completed by S1 using a micro-injection pump, and the injection time of the demulsifier is defined as the demulsification start time T0 in order to establish a standardized time reference.

[0014] S3, Temporal 3D Image Acquisition

[0015] Starting from the injection of demulsifier into S2, the laser confocal microscope is controlled to perform Z-axis scanning according to a set time sequence (T1, T2, ... T) during the demulsification process to acquire a continuous three-dimensional image data stack of the emulsion structure under the action of the demulsifier; the system can automatically adjust the acquisition frequency according to the demulsification rate, with high frequency in the early stage and low frequency in the later stage.

[0016] S4, Dynamic 3D Reconstruction and Quantitative Analysis

[0017] The three-dimensional image data acquired in each time series in S3 are reconstructed to generate a three-dimensional model sequence that changes over time; key dynamic parameters, including droplet coalescence rate, phase separation rate, demulsification efficiency index, and interface migration trajectory, are extracted using image processing and computational algorithms.

[0018] S5. Identification and Evaluation of Marrow Breaking Effect

[0019] Based on the changing trends of the kinetic parameters in S4, the efficiency and speed of the demulsifier are comprehensively judged, achieving an objective, quantitative, and comparable evaluation of the demulsifier's effectiveness; at the same time, dynamic 3D rendering videos and parameter change curves can be generated.

[0020] Furthermore, the sample cell in S1 includes an injection end, an injection section, a mixing tank, and a collection end, wherein: the injection end is used to inject the emulsion to be tested; the injection section is connected to a microfluidic control device or an injection pump to precisely control the injection flow rate and speed of the demulsifier; the mixing tank is provided with a flow channel and a transparent observation window, which can realize three-dimensional imaging under a laser confocal microscope; and the collection end is used to discharge the liquid after the demulsification process is completed.

[0021] Furthermore, the formulas for the dynamic parameters in S4 are as follows:

[0022] Droplet coalescence rate, characterizing the rate at which the average droplet size increases with time during demulsification, is defined as:

[0023]

[0024] Where: D0: average droplet diameter at the start of demulsification t0 (unit: µm); D t R: Average droplet diameter at time t (µm); C : Average droplet size growth rate (unit: µm / min); Average droplet diameter D is calculated from the droplet volume equivalent sphere diameter;

[0025]

[0026] In the formula: V i The volume of the i-th droplet (unit: µm) 3 N is the total number of droplets;

[0027] Phase separation rate: the rate of oil-water interface clearing and migration; defined as:

[0028]

[0029] In the formula: A t :time Percentage of dispersed phase (or continuous phase) area in the field of view (unit: %); H t :time Oil-water interface height (unit: µm); R S Phase separation rate, reflecting the rate of change of the oil-water interface (unit: µm / min or % / min);

[0030] Demulsification efficiency index: the proportion of the separated phase volume to the total phase volume at a specific time point; defined as:

[0031]

[0032] In the formula: V separated (tx): in time The volume of the phase separated at time (unit: µm³); V total : Total sample volume within the microscopic field of view (unit: µm³); H d Demulsification efficiency index, expressed as a percentage (%).

[0033] Interface thickness and migration trajectory: reflect phase separation stability and speed; defined as:

[0034]

[0035] In the formula: :time Interface thickness at that time (unit: µm); : Interface thickness at the initial moment of demulsification (unit: µm); Interface thickness change (unit: µm);

[0036] when A higher (µm / min) indicates a faster droplet coalescence rate and a stronger ability of the demulsifier to promote phase separation.

[0037] (µm / min or % / min) reflects the rate of macroscopic phase separation and is an important parameter for measuring demulsification rate;

[0038] (%) quantitatively reflects the degree of demulsification and is the core indicator for evaluating the efficiency of demulsifiers;

[0039] The value (µm) and its change curve over time can intuitively reflect the thinning of the oil-water interface, the drainage, and the separation trend.

[0040] Furthermore, the sample cell is made of a transparent solvent-resistant material, selected from one or more of polymethyl methacrylate (PMMA), quartz, or polytetrafluoroethylene (PTFE); the size of the sample cell is determined according to the working distance and field of view of the laser confocal microscope to ensure that the oil-water phase interface is always within the observation area during the emulsion layering process, and the flow channel width is 0.1-2 mm and the length is 5-20 mm.

[0041] Furthermore, the laser confocal microscope uses a 514nm wavelength laser as the excitation source to excite the fluorescence signal of the oil phase or labeled components in the emulsion; the receiving wavelength includes two bands, the first receiving band is 550-750nm, corresponding to the red or blue imaging channel, and the second receiving band is 400-480nm, corresponding to the green imaging channel, so as to distinguish the spatial distribution of the oil phase and the water phase through the dual-band signal.

[0042] Furthermore, the flow rate accuracy of the micro-injection pump is ≤0.1μL / min, and the injection flow rate of the demulsifier can be continuously adjusted within the range of 1-10μL / min; the injection method can be either continuous injection or intermittent injection, wherein the single injection volume of intermittent injection is 0.1-1μL, the injection interval is set to 10-60s according to the initial reaction rate of demulsification, and the injection action is synchronized with the start time of the microscope Z-axis scanning.

[0043] Furthermore, the automatic adjustment of the acquisition frequency in S3 is triggered by kinetic parameters. When the droplet coalescence rate (Rc) ≥ 0.5 μm / min or the phase separation rate (Rs) ≥ 1 μm / min, a high-frequency scanning mode is adopted with a scanning interval of 5-30 s / time. When Rc < 0.5 μm / min and Rs < 1 μm / min, the mode is switched to low-frequency scanning mode with a scanning interval of 1-5 min / time. During the scanning process, the Z-axis scanning range is maintained to cover the entire effective thickness of the sample cell.

[0044] Furthermore, in the dynamic three-dimensional reconstruction process in S4, a volume data interpolation algorithm is used to complete the pixel of the image stack obtained by Z-axis scanning, and the spatial resolution of the reconstructed three-dimensional model is ≤0.1μm; during quantitative analysis, the droplet boundary and oil-water interface are automatically identified by the image segmentation algorithm to eliminate interference signals from bubbles and impurities.

[0045] Compared with the prior art, the beneficial effects of the present invention are:

[0046] This invention, for the first time, extends laser confocal microscopy from static observation to online real-time dynamic imaging. It can continuously record the entire process of droplet coalescence, flocculation, interfacial migration, and phase separation under the action of demulsifiers, essentially providing a "real-time CT scan" of the demulsification process and completely solving the "black box" problem of traditional bottle testing methods. Through automatic 3D reconstruction and data analysis, it can extract key kinetic parameters such as droplet coalescence rate, phase separation rate, and demulsification efficiency index, achieving objective, standardized, and quantitative evaluation of demulsifier efficacy, overcoming the problems of strong subjectivity and poor repeatability of manual visual judgment. The system can automatically adjust the acquisition frequency according to the demulsification rate, reducing invalid data. Combined with automated data processing and analysis, it significantly shortens the time of a single experiment, reducing the experimental cycle to about 1 / 10 of the original, making it suitable for high-throughput screening and rapid optimization of demulsifiers. The dedicated online observation sample cell design prevents the oil-water interface from leaving the microscope field of view during demulsification, while simultaneously enabling precise synchronous injection of demulsifiers, ensuring repeatable experimental results and continuous and complete data. It provides real-time 3D visualization videos and kinetic data curves, which can intuitively reveal the action modes of different demulsifiers and provide reliable experimental basis for reagent design and process optimization; the method is applicable to multiple fields such as crude oil dehydration, sewage treatment, food and cosmetic emulsification systems. Attached Figure Description

[0047] Figure 1 This is a flowchart of a specific implementation plan for the identification and evaluation technology of online monitoring of the demulsification process using laser confocal microscopy;

[0048] Figure 2 This is a schematic diagram of a device for online monitoring of the demulsification process using a laser confocal microscope.

[0049] In the diagram: 1. Injection end; 2. Injection section; 3. Mixing tank; 4. Extraction end. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 are within the scope of protection of the present invention.

[0051] Please see Figure 1 —2: A method for identifying and evaluating demulsification during online monitoring using laser confocal microscopy. The specific steps of this method are as follows:

[0052] S1. Sample Cell Design and Sample Loading

[0053] The emulsion to be tested is injected into a specially designed online observation sample cell. The sample cell has an inlet and an outlet and is equipped with slit flow, dialysis or bilayer structure to ensure that the oil-water interface is always within the microscope observation range during the demulsification process, while allowing the demulsifier to be introduced and mixed in real time.

[0054] S2. Demulsifier introduction and process initialization

[0055] Demulsifier is precisely injected into the middle of the sample cell completed by S1 using a micro-injection pump, and the injection time of the demulsifier is defined as the demulsification start time T0 in order to establish a standardized time reference.

[0056] S3, Temporal 3D Image Acquisition

[0057] Starting from the injection of demulsifier into S2, the laser confocal microscope is controlled to perform Z-axis scanning according to a set time sequence (T1, T2, ... T) during the demulsification process to acquire a continuous three-dimensional image data stack of the emulsion structure under the action of the demulsifier; the system can automatically adjust the acquisition frequency according to the demulsification rate, with high frequency in the early stage and low frequency in the later stage.

[0058] S4, Dynamic 3D Reconstruction and Quantitative Analysis

[0059] The three-dimensional image data acquired in each time series in S3 are reconstructed to generate a three-dimensional model sequence that changes over time; key dynamic parameters, including droplet coalescence rate, phase separation rate, demulsification efficiency index, and interface migration trajectory, are extracted using image processing and computational algorithms.

[0060] S5. Identification and Evaluation of Marrow Breaking Effect

[0061] Based on the changing trends of the kinetic parameters in S4, the efficiency and speed of the demulsifier are comprehensively judged, achieving an objective, quantitative, and comparable evaluation of the demulsifier's effectiveness; at the same time, dynamic 3D rendering videos and parameter change curves can be generated.

[0062] The sample cell in S1 includes an injection end 1, an injection section 2, a mixing tank 3, and an extraction end 4, wherein: the injection end 1 is used to inject the emulsion to be tested; the injection section 2 is connected to a microfluidic control device or injection pump to precisely control the injection flow rate and speed of the demulsifier; the mixing tank 3 is equipped with a flow channel and a transparent observation window, which can realize three-dimensional imaging under a laser confocal microscope; the extraction end 4 is used to discharge the liquid after the demulsification process is completed.

[0063] The sample cell is made of a transparent solvent-resistant material, selected from one or more of polymethyl methacrylate (PMMA), quartz, or polytetrafluoroethylene (PTFE). The size of the sample cell is determined according to the working distance and field of view of the laser confocal microscope to ensure that the oil-water phase interface is always within the observation area during the emulsion layering process, and the flow channel width is 0.1-2 mm and the length is 5-20 mm.

[0064] Data acquisition and analysis software is installed on the computer to control microscope scanning, fluid device synchronization, and image processing.

[0065] The laser confocal microscope uses a 514nm wavelength laser as the excitation source to excite the fluorescence signal of the oil phase or labeled components in the emulsion. The receiving wavelength includes two bands: the first receiving band is 550-750nm, corresponding to the red or blue imaging channel, and the second receiving band is 400-480nm, corresponding to the green imaging channel. The spatial distribution of the oil phase and the water phase can be distinguished by the dual-band signal.

[0066] The flow rate accuracy of the micro-injection pump is ≤0.1μL / min, and the injection flow rate of the demulsifier can be continuously adjusted within the range of 1-10μL / min. The injection method can be either continuous injection or intermittent injection. The single injection volume of intermittent injection is 0.1-1μL, and the injection interval is set to 10-60s according to the initial reaction rate of demulsification. The injection action is synchronized with the start time of the microscope Z-axis scanning.

[0067] The automatic adjustment of the acquisition frequency in S3 is triggered by kinetic parameters. When the droplet coalescence rate (Rc) ≥ 0.5 μm / min or the phase separation rate (Rs) ≥ 1 μm / min, the high-frequency scanning mode is used with a scanning interval of 5-30 s / time. When Rc < 0.5 μm / min and Rs < 1 μm / min, the mode is switched to low-frequency scanning with a scanning interval of 1-5 min / time. During the scanning process, the Z-axis scanning range is kept to cover the entire effective thickness of the sample cell.

[0068] In the S4 dynamic 3D reconstruction process, a volume data interpolation algorithm is used to complete the pixel of the image stack obtained by Z-axis scanning. The spatial resolution of the reconstructed 3D model is ≤0.1μm. During quantitative analysis, the droplet boundary and oil-water interface are automatically identified by the image segmentation algorithm to eliminate interference signals from bubbles and impurities.

[0069] The experiment is as follows:

[0070] During the experimental procedure, the prepared emulsion to be tested was first injected into the sample cell through injection end 1, forming a stable observation area within the microscope's field of view. Subsequently, a micro-injection pump, controlled by injection section 2, precisely injected the demulsifier solution into the mixing tank 3 at a set flow rate (1–10 μL / min), ensuring full contact with the emulsion. The injection process was synchronized with the microscope scanning process, and the demulsifier injection time was defined as the demulsification initiation time T0.

[0071] The laser confocal microscope performs Z-axis scanning according to a set time sequence (T0, T1, T2, ..., T), continuously acquiring three-dimensional image data of the demulsification system in mixing tank 3. The system can automatically adjust the acquisition frequency according to the demulsification rate. High-frequency scanning is used in the early stage of demulsification to capture rapid aggregation behavior, and the acquisition frequency is reduced in the later stage to save storage and maintain monitoring continuity.

[0072] The acquired image data is automatically reconstructed and segmented in 3D by a computer control system to obtain a dynamic 3D model of the demulsification process. Based on the image analysis results, the system extracts the following dynamic characteristic parameters:

[0073] Droplet coalescence rate, characterizing the rate at which the average droplet size increases with time during demulsification, is defined as:

[0074]

[0075] Where: D0: average droplet diameter at the start of demulsification t0 (unit: µm); D t R: Average droplet diameter at time t (µm); C : Average droplet size growth rate (unit: µm / min); Average droplet diameter D is calculated from the droplet volume equivalent sphere diameter;

[0076]

[0077] In the formula: V i The volume of the i-th droplet (unit: µm) 3 N is the total number of droplets;

[0078] Phase separation rate: the rate of oil-water interface clearing and migration; defined as:

[0079]

[0080] In the formula: A t :time Percentage of dispersed phase (or continuous phase) area in the field of view (unit: %); H t :time Oil-water interface height (unit: µm); R S Phase separation rate, reflecting the rate of change of the oil-water interface (unit: µm / min or % / min);

[0081] Demulsification efficiency index: the proportion of the separated phase volume to the total phase volume at a specific time point; defined as:

[0082]

[0083] In the formula: V separated (tx): in time The volume of the phase separated at time (unit: µm³); V total : Total sample volume within the microscopic field of view (unit: µm³); H d Demulsification efficiency index, expressed as a percentage (%).

[0084] Interface thickness and migration trajectory: reflect phase separation stability and speed; defined as:

[0085]

[0086] In the formula: :time Interface thickness at that time (unit: µm); : Interface thickness at the initial moment of demulsification (unit: µm); Interface thickness change (unit: µm);

[0087] when A higher (µm / min) indicates a faster droplet coalescence rate and a stronger ability of the demulsifier to promote phase separation.

[0088] (µm / min or % / min) reflects the rate of macroscopic phase separation and is an important parameter for measuring demulsification rate;

[0089] (%) quantitatively reflects the degree of demulsification and is the core indicator for evaluating the efficiency of demulsifiers;

[0090] The value (µm) and its change curve over time can intuitively reflect the thinning of the oil-water interface, the drainage, and the separation trend.

[0091] Simultaneously, the system performs pseudo-color rendering of the 3D model at each time point, generating a dynamic video sequence of the demulsification process, intuitively demonstrating processes such as droplet coalescence, flocculation, and interface migration. All experimental data are stored in real time and can be exported for statistical analysis.

[0092] After the demulsification process is completed, the liquid in the mixing tank is discharged through the extraction end 4, enabling system renewal and repeated testing. The entire experimental process is highly automated, with a single test time of approximately 1 / 10 of the traditional bottle test method, and complete kinetic parameters and visualized process data can be obtained.

Claims

1. A method for identifying and evaluating demulsification during online monitoring using laser confocal microscopy, characterized by: The specific steps of this method are as follows: S1. Sample Cell Design and Sample Loading The emulsion to be tested is injected into a specially designed online observation sample cell. The sample cell has an inlet and an outlet and is equipped with slit flow, dialysis or bilayer structure to ensure that the oil-water interface is always within the microscope observation range during the demulsification process, while allowing the demulsifier to be introduced and mixed in real time. S2. Demulsifier introduction and process initialization Demulsifier is precisely injected into the middle of the sample cell completed by S1 using a micro-injection pump, and the injection time of the demulsifier is defined as the demulsification start time T0 in order to establish a standardized time reference. S3, Temporal 3D Image Acquisition Starting from the injection of demulsifier into S2, the laser confocal microscope is controlled to perform Z-axis scanning according to a set time sequence (T1, T2, ... T) during the demulsification process to acquire a continuous three-dimensional image data stack of the emulsion structure under the action of the demulsifier; the system can automatically adjust the acquisition frequency according to the demulsification rate, with high frequency in the early stage and low frequency in the later stage. S4, Dynamic 3D Reconstruction and Quantitative Analysis The three-dimensional image data acquired in each time series in S3 are reconstructed to generate a three-dimensional model sequence that changes over time; key dynamic parameters, including droplet coalescence rate, phase separation rate, demulsification efficiency index, and interface migration trajectory, are extracted using image processing and computational algorithms. S5. Identification and Evaluation of Marrow Breaking Effect Based on the changing trends of the kinetic parameters in S4, the efficiency and speed of the demulsifier are comprehensively judged, achieving an objective, quantitative, and comparable evaluation of the demulsifier's effectiveness; at the same time, dynamic 3D rendering videos and parameter change curves can be generated.

2. The method for online monitoring, identification, and evaluation of demulsification using laser confocal microscopy according to claim 1, characterized in that: The sample cell in S1 includes an injection end (1), an injection section (2), a mixing tank (3), and a collection end (4), wherein: the injection end (1) is used to inject the emulsion to be tested; the injection section (2) is connected to a microfluidic control device or an injection pump to precisely control the injection flow rate and speed of the demulsifier; the mixing tank (3) is equipped with a flow channel and a transparent observation window, which can realize three-dimensional imaging under a laser confocal microscope; the collection end (4) is used to discharge the liquid after the demulsification process is completed.

3. The method for online monitoring, identification, and evaluation of demulsification using laser confocal microscopy according to claim 2, characterized in that: The formulas for the dynamic parameters in S4 are as follows: Droplet coalescence rate, characterizing the rate at which the average droplet size increases with time during demulsification, is defined as: Where: D0: average droplet diameter at the start of demulsification t0 (unit: µm); D t R: Average droplet diameter at time t (µm); C : Average droplet size growth rate (unit: µm / min); Average droplet diameter D is calculated from the droplet volume equivalent sphere diameter; In the formula: V i The volume of the i-th droplet (unit: µm) 3 N is the total number of droplets; Phase separation rate: the rate of oil-water interface clearing and migration; defined as: In the formula: A t :time Percentage of dispersed phase (or continuous phase) area in the field of view (unit: %); H t :time Oil-water interface height (unit: µm); R S Phase separation rate, reflecting the rate of change of the oil-water interface (unit: µm / min or % / min); Demulsification efficiency index: the proportion of the separated phase volume to the total phase volume at a specific time point; defined as: In the formula: V separated (tx): in time The volume of the separated phase at time (unit: µm³); V total : Total sample volume within the microscopic field of view (unit: µm³); H d Demulsification efficiency index, expressed as a percentage (%). Interface thickness and migration trajectory: reflect phase separation stability and speed; defined as: In the formula: :time Interface thickness at that time (unit: µm); : Interface thickness at the initial moment of demulsification (unit: µm); Interface thickness change (unit: µm); when A higher (µm / min) indicates a faster droplet coalescence rate and a stronger ability of the demulsifier to promote phase separation. (µm / min or % / min) reflects the rate of macroscopic phase separation and is an important parameter for measuring demulsification rate; (%) quantitatively reflects the degree of demulsification and is the core indicator for evaluating the efficiency of demulsifiers; The value (µm) and its change curve over time can intuitively reflect the thinning of the oil-water interface, the drainage, and the separation trend.

4. The method for online monitoring, identification, and evaluation of demulsification using laser confocal microscopy according to claim 2, characterized in that: The sample cell is made of a transparent solvent-resistant material, selected from one or more of polymethyl methacrylate, quartz, or polytetrafluoroethylene. The size of the sample cell is determined according to the working distance and field of view of the laser confocal microscope to ensure that the oil-water phase interface is always within the observation area during the emulsion layering process, and the width of the flow channel is 0.1-2 mm and the length is 5-20 mm.

5. The method for online monitoring, identification, and evaluation of demulsification using laser confocal microscopy according to claim 1, characterized in that: The laser confocal microscope uses a 514nm wavelength laser as the excitation source to excite the fluorescence signal of the oil phase or labeled components in the emulsion; the receiving wavelength includes two bands, the first receiving band is 550-750nm, corresponding to the red or blue imaging channel, and the second receiving band is 400-480nm, corresponding to the green imaging channel, so as to distinguish the spatial distribution of the oil phase and the water phase through the dual-band signal.

6. The method for online monitoring, identification, and evaluation of demulsification using laser confocal microscopy according to claim 1, characterized in that: The flow rate accuracy of the micro-injection pump is ≤0.1μL / min, and the injection flow rate of the demulsifier can be continuously adjusted within the range of 1-10μL / min; The injection method can be either continuous injection or intermittent injection. The single injection volume for intermittent injection is 0.1-1 μL, and the injection interval is set to 10-60 s according to the initial reaction rate of demulsification. The injection action is synchronized with the start time of the microscope Z-axis scan.

7. The method for online monitoring, identification, and evaluation of demulsification using laser confocal microscopy according to claim 1, characterized in that: The automatic adjustment of the acquisition frequency in S3 is triggered by kinetic parameters. When the droplet coalescence rate Rc ≥ 0.5 μm / min or the phase separation rate Rs ≥ 1 μm / min, a high-frequency scanning mode is adopted with a scanning interval of 5-30 s / time. When Rc < 0.5 μm / min and Rs < 1 μm / min, the mode is switched to low-frequency scanning mode with a scanning interval of 1-5 min / time. During the scanning process, the Z-axis scanning range is kept to cover the entire effective thickness of the sample cell.

8. The method for online monitoring, identification, and evaluation of demulsification using laser confocal microscopy according to claim 1, characterized in that: The dynamic three-dimensional reconstruction process in S4 uses a volume data interpolation algorithm to complete the pixel of the image stack obtained by Z-axis scanning. The spatial resolution of the reconstructed three-dimensional model is ≤0.1μm. During quantitative analysis, the droplet boundary and oil-water interface are automatically identified by the image segmentation algorithm to eliminate interference signals from bubbles and impurities.

Images