Visual detection method for generation of interface water microdroplet induced electrons in high-temperature and high-pressure hydrocarbon-water system

Abstract

The invention provides a visual detection method for interface water droplet induced electron generation in a high-temperature and high-pressure hydrocarbon-water system, and belongs to the technical field of in-situ analysis of electrons in mixed fluid. The detection method comprises the following steps: preparing a fused quartz capillary reaction cavity; loading a sample in a fused quartz capillary reaction cavity: sequentially inserting a thin capillary syringe filled with a silicomolybdic acid aqueous solution and a thin capillary syringe filled with a hydrocarbon liquid into the fused quartz capillary reaction cavity, and injecting the silicomolybdic acid aqueous solution and the hydrocarbon liquid; and carrying out visual detection on the water droplets. Through the visual fused quartz capillary thermal simulation experiment device, the color change of the water droplets at the interface of the silicomolybdic acid aqueous solution and the hydrocarbon fluid under the conditions of high temperature and high pressure is visually displayed, and the color characteristics of the water droplets are observed in real time by using a microscope, so that whether the water droplets induce electron generation or not is judged; the problem that electrons generated by water droplets cannot be directly observed and detected under high-temperature and high-pressure conditions is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of in-situ electron analysis in mixed fluids, and particularly relates to a visual detection method for electron generation induced by interfacial water microdroplets in a high-temperature and high-pressure hydrocarbon-water system. BACKGROUND

[0002] A hydrocarbon-water interface is widely developed in deep oil and gas reservoirs, and a large number of water microdroplets are formed at the hydrocarbon-water interface under the action of high temperature and high pressure. Compared with bulk water, water microdroplets have more active physical and chemical properties. Studies have shown that a strong electric field (~10 9 V / m) is distributed on the surface of water microdroplets, which can induce OH - to lose electrons, thereby forming free electrons and enabling many redox reactions that cannot be realized in bulk water to occur, which has a profound impact on energy transfer and material conversion in deep oil and gas reservoirs.

[0003] Due to the action of high temperature and high pressure, the reaction characteristics of hydrocarbons and water in deep oil and gas reservoirs are more complex than under normal temperature conditions, and the electron activity inside is also more difficult to observe. At present, methyl viologen, resazurin and other organic electron probes are commonly used to capture electrons generated by water microdroplets under room temperature conditions, and fluorescence or ultraviolet spectroscopy is used to indicate the generation of electrons. However, under high temperature and high pressure conditions, these common electron indicators will lose effectiveness due to high temperature, and it is difficult to continue to play the role of electron probes.

[0004] Therefore, it is urgent to develop a stable detection method to directly and conveniently detect the generation of electrons induced by water microdroplets under high temperature and high pressure conditions, and to provide a scientific basis for explaining the organic-inorganic interface interaction and material conversion processes in deep oil and gas reservoirs. SUMMARY

[0005] The purpose of the present application is to provide a visual detection method for electron generation induced by interfacial water microdroplets in a high-temperature and high-pressure hydrocarbon-water system, which solves the problem that the prior art cannot effectively detect whether electron generation can be induced by interfacial water microdroplets in a hydrocarbon-water system under high temperature and high pressure conditions.

[0006] In order to achieve the above-mentioned purpose of the application, the present application provides the following technical solutions: The present application provides a visual detection method for electron generation induced by interfacial water microdroplets in a high-temperature and high-pressure hydrocarbon-water system, comprising the following steps: 1) Preparing a fused quartz capillary reaction chamber: one end of the fused quartz capillary is welded and sealed, and is inserted into a conical sleeve filled with AB glue until the end protrudes from the conical sleeve. After the fused quartz capillary and the conical sleeve are bonded and fixed, dry them, cut off the protruding capillary in the conical sleeve, and form an opening as a sample injection end; Remove the polyimide coating of the end of the fused silica capillary not sealed by welding to form a visual window, and close the end with the visual window by using a hydrogen-oxygen welding gun; 2) Sample loading in the fused silica capillary reaction chamber: insert the fine capillary syringe containing the aqueous silicomolybdic acid solution into the fused silica capillary reaction chamber until the closed end of the visual window, and inject the aqueous silicomolybdic acid solution; Insert the fine capillary syringe containing the hydrocarbon liquid into the fused silica capillary reaction chamber until the middle of the visual window, inject the hydrocarbon liquid, and observe the contact interface of the hydrocarbon liquid and the aqueous silicomolybdic acid solution in the visual window. When the system is free of impurities and bubbles, the sample loading is completed. 3) Visual detection of water droplets: connect the sample-loaded fused silica capillary reaction chamber with the high-pressure needle valve, then insert it into the cooling and heating table, and place the visual window of the fused silica capillary reaction chamber above the temperature control plate of the cooling and heating table. Use a silver sheet to fix the fused silica capillary reaction chamber. Gradually increase the temperature and pressure in the fused silica capillary reaction chamber by using the cooling and heating table and the constant-pressure liquid pump until water droplets form at the hydrocarbon-water interface. Observe the color change of the water droplets through a microscope.

[0007] Preferably, the cross-section of the fused silica capillary in step 1) is circular, the inner diameter of the fused silica capillary is 180-220 μm, the outer diameter is 760-830 μm, and the length is 18-22 cm.

[0008] Preferably, the sealing in step 1) is performed by using a hydrogen-oxygen welding gun and AB glue to fix the fused silica capillary and the conical sleeve. The drying temperature is 38-43℃, and the drying time is 22-26 h.

[0009] Preferably, in step 1), the length of the end protruding from the conical sleeve is 4-6 mm, and the length of the visual window is 3-5 cm.

[0010] Preferably, the length of the fine capillary syringe in step 2) is ≥20 cm, and the outer diameter is 150-180 μm.

[0011] Preferably, the fine capillary syringe is withdrawn outward while injecting the aqueous silicomolybdic acid solution, and the amount of the aqueous silicomolybdic acid solution injected is enough to fill the entire visual window. The fine capillary syringe is withdrawn outward while injecting the hydrocarbon liquid, and the excess aqueous silicomolybdic acid solution is discharged at the same time.

[0012] Preferably, the hydrocarbon liquid includes hexadecane, and the mass concentration of the aqueous silicomolybdic acid solution is 3.5-4.5 g / L.

[0013] Preferably, the contact interface of the hydrocarbon liquid and the aqueous silicomolybdic acid solution in the visual window of the fused silica capillary reaction chamber is above the temperature control plate of the cooling and heating table. The silver sheet is a hollow silver sheet with a long and narrow middle part.

[0014] Preferably, in step 3), the initial pressure is 4.8~5.2MPa, the initial temperature is 22~26℃, the set temperature is 150~170℃, and the set pressure is 14~16MPa.

[0015] The beneficial effects of this invention are: 1) This invention aims to clarify the color change reaction formed by the reduction of electrons generated by water droplets by molybdic acid electron indicator under high temperature and high pressure conditions. Based on the temperature and pressure conditions of actual deep oil and gas reservoirs, the color change phenomenon of water droplets at the interface between molybdic acid aqueous solution and hydrocarbon fluid under high temperature and high pressure conditions is observed through a visual fused silica capillary thermal simulation experiment. The color characteristics of molybdic acid water droplets during high temperature and high pressure are clarified; the change of water droplets from pale yellow or colorless to dark blue or blue-green indicates the generation of electrons.

[0016] 2) This invention uses a visual fused silica capillary thermal simulation experimental device to intuitively display the color change phenomenon of water droplets at the interface between aqueous solution of molybdic acid and hydrocarbon fluid under high temperature and high pressure. The color characteristics of water droplets are observed in real time using a microscope, thereby determining whether water droplets induce electron generation. This solves the problem that electrons generated by water droplets under high temperature and high pressure cannot be directly observed and detected. Attached Figure Description

[0017] Figure 1 This invention provides a visual fusion silica capillary thermal simulation experimental apparatus. Figure 2 This is a characteristic image of the interface between the aqueous solution of molybdic acid and hexadecane in the fused silica capillary reaction chamber of Example 1 under initial temperature and pressure (25°C / 5MPa). Figure 3 Image of water droplets at the interface between aqueous molybdic acid and hexadecane in a fused silica capillary reaction chamber under high temperature and high pressure (160℃ / 15MPa) in Example 1; Figure 4 This is a comparison diagram of the aqueous solution of molybdic acid, the mixture of molybdic acid powder and hexadecane, and the mixture of aqueous solution of molybdic acid and hexadecane after high-temperature reaction in Example 4. Detailed Implementation

[0018] This invention provides a visual detection method for electron generation induced by interfacial water droplets in a high-temperature, high-pressure hydrocarbon-water system, comprising the following steps: 1) Preparation of fused silica capillary reaction chamber: Weld one end of the fused silica capillary and insert it into a conical sleeve filled with AB glue until the end protrudes from the conical sleeve. After the fused silica capillary and the conical sleeve are bonded and fixed, dry them and cut off the capillary protruding from the conical sleeve to form an opening, which serves as the sample injection end. Remove the polyimide coating from the unsealed end of the fused silica capillary to form a viewing window, and seal the end with the viewing window using an oxyhydrogen welding torch. 2) Sample loading in the fused silica capillary reaction chamber: Insert a fine capillary syringe containing an aqueous solution of molybdic acid into the fused silica capillary reaction chamber until the closed end of the viewing window is reached, and inject the aqueous solution of molybdic acid. Insert a fine capillary syringe containing hydrocarbon liquid into the fused silica capillary reaction chamber until the middle of the viewing window, inject the hydrocarbon liquid, and observe the contact interface between the hydrocarbon liquid and the aqueous solution of molybdic acid in the viewing window. When the system is free of impurities and bubbles, the sample loading is complete. 3) Visual detection of water droplets: The fused silica capillary reaction chamber after sample loading is connected to the high-pressure needle valve and then inserted into the hot and cold stage. The viewing window of the fused silica capillary reaction chamber is located above the temperature control plate of the hot and cold stage. The fused silica capillary reaction chamber is fixed with a silver sheet. The temperature and pressure in the molten quartz capillary reaction chamber were gradually increased using a hot and cold stage and a constant pressure liquid pump until water droplets formed at the hydrocarbon-water interface. The color changes of the water droplets were then observed under a microscope.

[0019] The visual fused silica capillary thermal simulation experimental apparatus of the present invention is as follows: Figure 1 As shown, the experimental setup includes a high-temperature and high-pressure visualization micron-sized quartz tube simulation system, a microscope, and a photography system. The high-temperature and high-pressure visualization micron-sized quartz tube simulation system includes a fused silica capillary reaction chamber, a constant pressure liquid pump, a high-pressure needle valve, a digital pressure sensor, a slide rail, a hot and cold stage, a high-pressure stainless steel tube, and a matching conical sleeve.

[0020] In this invention, the cross-section of the fused silica capillary in step 1) is preferably circular, the inner diameter of the fused silica capillary is preferably 180~220μm, more preferably 190~210μm, more preferably 201~203μm, the outer diameter is preferably 760~830μm, more preferably 780~810μm, more preferably 790~795μm, and the length is preferably 18~22cm, more preferably 19~21cm, more preferably 20cm.

[0021] In this invention, the welding seal in step 1) is preferably achieved using an oxyhydrogen welding gun, with AB glue used to bond and fix the fused silica capillary and the conical sleeve; the drying temperature is preferably 38~43℃, more preferably 39~41℃, and even more preferably 40℃; the drying time is preferably 22~26h, more preferably 23~25h, and even more preferably 24h.

[0022] In this invention, the purpose of welding one end of the fused silica capillary is to prevent AB glue from entering the interior of the quartz capillary during the fixing process.

[0023] In step 1) of the present invention, the length of the end protruding from the conical sleeve is preferably 4~6mm, more preferably 4.5~5.5mm, and even more preferably 5mm; the length of the viewing window is preferably 3~5cm, more preferably 3.5~4.5cm, and even more preferably 4cm.

[0024] In this invention, the length of the capillary syringe in step 2) is preferably ≥20cm, and the outer diameter is preferably 150~180μm, more preferably 160~170μm.

[0025] In this invention, the capillary syringe is withdrawn while injecting the aqueous solution of molybdenum silicoamic acid, and the amount of aqueous solution injected is preferably enough to fill the entire viewing window; the capillary syringe is withdrawn while injecting the hydrocarbon liquid, and excess aqueous solution of molybdenum silicoamic acid is discharged while injecting the hydrocarbon liquid.

[0026] In this invention, the hydrocarbon liquid preferably includes hexadecane, and the mass concentration of the aqueous solution of molybdic acid is preferably 3.5~4.5 g / L, more preferably 3.8~4.2 g / L, and even more preferably 4 g / L.

[0027] In this invention, the contact interface between the hydrocarbon liquid and the aqueous solution of molybdenum silicate in the viewing window of the fused silica capillary reaction chamber is located above the temperature control plate of the hot and cold stage; the silver sheet is preferably a long and thin hollowed-out silver sheet in the middle.

[0028] In this invention, the initial pressure in step 3) is preferably 4.8~5.2MPa, more preferably 5MPa; the initial temperature is preferably 22~26℃, more preferably 24~25℃; the set temperature is preferably 150~170℃, more preferably 155~165℃, more preferably 160℃; and the set pressure is preferably 14~16MPa, more preferably 15MPa.

[0029] In this invention, molybdic acid changes from yellow to deep blue or blue-green after capturing electrons. During the experiment, water droplets are generated by controlling temperature and pressure changes within the capillary. These droplets are then observed in situ using a microscope to monitor color changes and determine whether electrons are generated. The specific method for qualitative analysis of electrons induced by water droplets using microscopy involves designing reaction conditions based on the actual temperature and pressure range in deep oil and gas reservoirs. A hot / cold stage and a constant-pressure pump are used to control the temperature and pressure of the fused silica capillary reaction chamber. A microscope is used to observe the changes in temperature and pressure at the hydrocarbon-water interface. If water droplets appear at the interface, a photographic system is used to monitor their color changes in real time, determining whether the droplet color changes from colorless or pale yellow to deep blue or yellow-green, thus confirming electron generation.

[0030] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0031] In this embodiment, the experimental setup includes a high-temperature, high-pressure visualization micron-sized quartz tube simulation system (HTHPOC), a microscope (Zeiss LSM700), and a photographic system. The high-temperature and high-pressure visualization micron-sized quartz tube simulation system includes a fused silica capillary reaction chamber (FSCC), a constant pressure liquid pump (HYHY-100B), a high-pressure needle valve (30-15HF4, 30000psi), a digital pressure sensor (0~150MPa), a slide rail, a hot and cold stage (LinkamCAP-500, -196~500℃, ±0.1℃), a high-pressure stainless steel tube, and a matching conical sleeve. The digital pressure sensor is located at the connection between the high-pressure needle valve and the fused silica capillary reaction chamber. The high-pressure needle valve is fixed on the slide rail, which is a manual precision fine-tuning handwheel slide rail (screw model 1204). The fused silica capillary tube is 20cm long, with an inner diameter of 202μm and an outer diameter of 794μm; the conical sleeve is composed of a hollow stainless steel tube with an inner diameter of 2mm and a length of 2cm and a stainless steel ball valve assembly; the AB glue is Hongxing brand fully transparent 509 AB glue produced by Ningbo Tiandong Adhesive Co., Ltd.; and the model of the forced-air drying oven is DHG-9075A.

[0032] Example 1

[0033] (1) Preparation of fused silica capillary reaction chamber

[0034] One end of the fused silica capillary is sealed with an oxyhydrogen welding torch and inserted into a conical sleeve filled with AB glue until the end protrudes 5mm from the conical sleeve. The fused silica capillary and the conical sleeve are then bonded and fixed with AB glue and left to dry at 40℃ for 24 hours. After the AB glue solidifies, the part of the capillary protruding from the conical sleeve is cut off to form an opening. Finally, the polyimide coating on the unsealed end of the fused silica capillary is removed to form a 4cm long viewing window. The end with the viewing window is then sealed with an oxyhydrogen welding torch.

[0035] (2) Sample loading in fused silica capillary reaction chamber

[0036] Preparation of an aqueous solution containing molybdic acid electronic indicator: Place 0.4 g of anhydrous molybdic acid powder into a 100 mL glass sample bottle, pour 100 mL of deionized water into the sample bottle containing the anhydrous molybdic acid powder, and seal the bottle to obtain a 4 g / L molybdic acid aqueous solution. A fused silica capillary with a circular cross-section, an outer diameter of 150 μm and a length of 25 cm, was connected to a disposable syringe with a capacity of 2.5 mL. The interface between the syringe and the capillary was glued with AB glue, with the glued position 2 cm away from the top of the quartz capillary. After cleaning the glue seeping from the wall of the quartz capillary, the quartz capillary was placed in a forced-air drying oven and dried at a constant temperature of 40°C for 24 hours to allow the glue to cure, thus obtaining a fine capillary syringe. Insert a fine capillary syringe filled with an aqueous solution of molybdate-silica into the opening of the conical sleeve until it reaches the closed end of the viewing window. While injecting the aqueous solution of molybdate-silica, simultaneously withdraw the fine capillary syringe until the entire viewing window is filled. Then, insert a fine capillary syringe filled with liquid hexadecane into the opening of the conical sleeve until it reaches the middle of the viewing window. Begin injecting the liquid hexadecane and expelling any excess aqueous solution of molybdate-silica. While injecting the liquid hexadecane, simultaneously withdraw the fine capillary syringe. A clear contact interface between the liquid hexadecane and the aqueous solution of molybdate-silica should be visible in the viewing window. The sample loading is complete when the entire system is free of impurities or bubbles.

[0037] (3) Visual detection of water droplets

[0038] The fused silica capillary reaction chamber, after sample loading, was connected to a high-pressure needle valve. The viewing window was cleaned with degreased cotton soaked in anhydrous alcohol and then inserted into the heating and cooling stage. The viewing window section (the interface between the hydrocarbon liquid and the aqueous solution of molybdic acid) of the fused silica capillary reaction chamber was positioned above the temperature control plate of the heating and cooling stage. The fused silica capillary reaction chamber was then fixed with a long, thin, hollowed-out silver sheet to prevent it from shaking or tilting upwards. Subsequently, the temperature and pressure changes in the fused silica capillary reaction chamber were controlled using the heating and cooling stage and a constant-pressure liquid pump. The initial temperature was 25℃, the initial pressure was 5MPa, the set temperature was 160℃, the set pressure was 15MPa, the heating rate was 10℃ / min, and the pressure rate was 5MPa / min. The interface between the aqueous solution of molybdic acid and the hexadecane liquid in the fused silica capillary reaction chamber and the presence of water droplets near the interface were monitored in real time using a microscope, and the color of the water droplets was observed to be different.

[0039] The characteristic image of the interface between the aqueous solution of molybdenum silicoside and hexadecane in the fused silica capillary reaction chamber under the initial temperature and pressure (25℃ / 5MPa) of this embodiment is shown below. Figure 2 As shown, by Figure 2 It can be seen that when the fused silica capillary is under the initial temperature (25℃) and initial pressure (5MPa) conditions, no microdroplets are formed at the interface between the aqueous solution of molybdic acid and hexadecane.

[0040] In this embodiment, the water droplets at the interface between the aqueous solution of molybdenum siliceous acid and hexadecane in a fused silica capillary reaction chamber under high temperature and high pressure (160℃ / 15MPa) are shown in the image below. Figure 3 As shown, byFigure 3 It can be seen that when the temperature rises to 160℃ and the pressure rises to 15MPa, the interface between the aqueous solution of molybdic acid and hexadecane begins to change, and water droplets are formed on the hexadecane side, and the color of the droplets gradually turns dark blue.

[0041] Example 2

[0042] 0.37 g of anhydrous molybdic acid powder was placed into a sample bottle, and 100 mL of deionized water was injected into the sample bottle containing the anhydrous molybdic acid powder. The bottle was then capped to obtain a 3.7 g / L molybdic acid aqueous solution. The initial temperature was 23 °C, the initial pressure was 4.8 MPa, the set temperature was 155 °C, and the set pressure was 14.5 MPa. Other process conditions were the same as in Example 1.

[0043] Example 3

[0044] 0.43 g of anhydrous molybdic acid powder was placed into a sample bottle, and 100 mL of deionized water was injected into the sample bottle containing the anhydrous molybdic acid powder. The bottle was then sealed to obtain a 4.3 g / L molybdic acid aqueous solution. The initial temperature was 27 °C, the initial pressure was 5.2 MPa, the set temperature was 165 °C, and the set pressure was 15.5 MPa. Other process conditions were the same as in Example 1.

[0045] Example 4

[0046] To determine the stability of molybdic acid electronic indicators under high-temperature conditions, the following steps were performed: The experimental setup consisted of 5mL transparent glass sample bottles and a forced-air drying oven (DHG-9075A). (1) Preparation of solution and sample loading Preparation of aqueous solution and sample loading of molybdic acid electronic indicator: Place 0.4 g of anhydrous molybdic acid powder into a sample vial, add 100 mL of deionized water to the sample vial containing the anhydrous molybdic acid powder, and cap the vial to obtain a 4 g / L molybdic acid aqueous solution; then use a pipette to transfer 2 mL of the molybdic acid aqueous solution into a 5 mL transparent glass sample vial, and then use argon gas to purge the air from the sample vial for 5 min, and then cap and seal the vial. Preparation of a mixture of molybdic acid powder and hexadecane: The molybdenum silicate powder was dried in a forced-air drying oven at 120°C for 2 hours. 0.2 g of the dried molybdenum silicate powder was placed into a 5 mL transparent glass sample bottle. Then, 2 mL of hexadecane was transferred into the sample bottle using a pipette. The sample bottle was then purged with argon gas for 5 minutes to remove the air. The bottle was then sealed with the cap. Preparation of a mixture of aqueous solution of molybdic acid and hexadecane: Use a pipette to transfer 1 mL of the prepared molybdic acid aqueous solution into a 5 mL transparent glass sample bottle, then transfer 1 mL of hexadecane into the sample bottle, and then use argon gas to purge the air from the sample bottle for 5 min, and then seal the bottle with the cap.

[0047] (2) Visualization of thermal simulation experiment process

[0048] Place all assembled samples into a DHG-9075A forced-air drying oven, set the temperature to 160℃, and the reaction time to 2 hours. After heating is complete, remove all sample vials and observe the color change of the samples in the vials.

[0049] A comparison diagram of the aqueous solution of molybdic acid, the mixture of molybdic acid powder and hexadecane, and the mixture of aqueous solution of molybdic acid and hexadecane after high-temperature reaction in Example 4 is shown below. Figure 4 As shown, by Figure 4 It can be seen that no color change was observed after the reaction of aqueous solution of molybdic acid, powder of molybdic acid and mixture of hexadecane, but after the reaction of aqueous solution of molybdic acid and mixture of hexadecane, the color of aqueous solution of molybdic acid changed significantly to blue-green.

[0050] As can be seen from the above embodiments, the present invention provides a visual thermal simulation experimental detection method for online detection of water droplets generated and electrons produced in a hydrocarbon-water system under high temperature and high pressure using molybdenum silymaric acid as an electronic indicator. The present invention uses molybdenum silymaric acid as an electronic indicator to explore whether water droplets at the hydrocarbon-water interface under high temperature and high pressure can induce electron generation and achieve visual detection. The present invention utilizes a hot and cold stage and a constant pressure liquid pump to control the temperature and pressure in the capillary and generate water droplets at the hydrocarbon-water interface. The color characteristics of the water droplets containing the molybdenum silymaric acid electronic indicator are observed online and in situ using a microscope to further determine whether the water droplets at the hydrocarbon-water interface can induce electron generation. This solves the problem of whether water droplets at the hydrocarbon-water interface can induce electron generation and be effectively detected under high temperature and high pressure conditions.

[0051] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A visual detection method for electron generation induced by interfacial water droplets in a high-temperature, high-pressure hydrocarbon-water system, characterized in that, It includes the following steps: 1) Preparation of fused silica capillary reaction chamber: Weld one end of the fused silica capillary and insert it into a conical sleeve filled with AB glue until the end protrudes from the conical sleeve. After the fused silica capillary and the conical sleeve are bonded and fixed, dry them and cut off the capillary protruding from the conical sleeve to form an opening, which serves as the sample injection end. Remove the polyimide coating from the unsealed end of the fused silica capillary to form a viewing window, and seal the end with the viewing window using an oxyhydrogen welding torch. 2) Sample loading in the fused silica capillary reaction chamber: Insert a fine capillary syringe containing an aqueous solution of molybdic acid into the fused silica capillary reaction chamber until the closed end of the viewing window is reached, and inject the aqueous solution of molybdic acid. Insert a fine capillary syringe containing hydrocarbon liquid into the fused silica capillary reaction chamber until the middle of the viewing window, inject the hydrocarbon liquid, and observe the contact interface between the hydrocarbon liquid and the aqueous solution of molybdic acid in the viewing window. When the system is free of impurities and bubbles, the sample loading is complete. 3) Visual detection of water droplets: The fused silica capillary reaction chamber after sample loading is connected to the high-pressure needle valve and then inserted into the hot and cold stage. The viewing window of the fused silica capillary reaction chamber is located above the temperature control plate of the hot and cold stage. The fused silica capillary reaction chamber is fixed with a silver sheet. The temperature and pressure in the molten quartz capillary reaction chamber were gradually increased using a hot and cold stage and a constant pressure liquid pump until water droplets formed at the hydrocarbon-water interface. The color changes of the water droplets were then observed under a microscope.

2. The visual detection method for electron generation induced by interfacial water droplets in a high-temperature, high-pressure hydrocarbon-water system according to claim 1, characterized in that, Step 1) The fused silica capillary has a circular cross-section, with an inner diameter of 180~220μm, an outer diameter of 760~830μm, and a length of 18~22cm.

3. The visual detection method for electron generation induced by interfacial water droplets in a high-temperature, high-pressure hydrocarbon-water system according to claim 1 or 2, characterized in that, Step 1) The welding seal is performed using an oxyhydrogen welding gun, and AB glue is used to bond and fix the fused silica capillary and the conical sleeve; the drying temperature is 38~43℃, and the drying time is 22~26h.

4. The visual detection method for electron generation induced by interfacial water droplets in a high-temperature, high-pressure hydrocarbon-water system according to claim 3, characterized in that, In step 1), the length of the end protruding from the conical sleeve is 4~6mm, and the length of the viewing window is 3~5cm.

5. The visual detection method for electron generation induced by interfacial water droplets in a high-temperature, high-pressure hydrocarbon-water system according to claim 4, characterized in that, Step 2) The capillary syringe has a length ≥20cm and an outer diameter of 150~180μm.

6. The visual detection method for electron generation induced by interfacial water droplets in a high-temperature, high-pressure hydrocarbon-water system according to claim 4 or 5, characterized in that, While injecting the aqueous solution of molybdenum silicate, withdraw the capillary syringe outwards. The amount of aqueous solution injected should fill the entire viewing window. While injecting the hydrocarbon liquid, withdraw the capillary syringe outwards. While injecting the hydrocarbon liquid, discharge the excess aqueous solution of molybdenum silicate.

7. The visual detection method for electron generation induced by interfacial water droplets in a high-temperature, high-pressure hydrocarbon-water system according to claim 6, characterized in that, The hydrocarbon liquid includes hexadecane, and the mass concentration of the aqueous solution of molybdic acid is 3.5~4.5 g / L.

8. The visual detection method for electron generation induced by interfacial water droplets in a high-temperature, high-pressure hydrocarbon-water system according to claim 7, characterized in that, The interface between the hydrocarbon liquid and the aqueous solution of molybdic acid in the visible window of the fused silica capillary reaction chamber is located above the temperature control plate of the hot and cold stage; the silver sheet is a long and thin hollowed-out silver sheet in the middle.

9. The visual detection method for electron generation induced by interfacial water droplets in a high-temperature, high-pressure hydrocarbon-water system according to claim 7 or 8, characterized in that, In step 3), the initial pressure is 4.8~5.2MPa, the initial temperature is 22~26℃, the set temperature is 150~170℃, and the set pressure is 14~16MPa.

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