In-situ monitoring device and method for mineral precipitation behavior in fluid mixing reaction process

Abstract

The invention discloses an in-situ monitoring device and an in-situ monitoring method for a mineral precipitation behavior in a fluid mixing reaction process, and belongs to the technical field of mineralogy monitoring. The device comprises a fluid injection and control system, a fluid mixing reaction device, a movably mounted sample table and an in-situ detection system (a microscopic optical detection device, a Raman detection device or a neutron emission and detection device). Sapphire wafer windows are arranged in front of and behind the fluid mixing reaction device, so that optical signals and neutron signals can penetrate through the sapphire wafer windows; the upper end of the fluid mixing reaction device is connected with a fluid injection system, and continuous and stable injection of fluid is controlled through a high-precision high-pressure injection pump; and the lower end of the fluid mixing reaction device is connected with a vacuum pump and a liquid outlet, so that a vacuum environment condition in the reaction device can be realized before reaction. The optical imaging method and the neutron scattering method can be used for monitoring mineral crystal nucleation and growth changes in real time, and full-size change monitoring of mineral nucleation and growth in the fluid mixing reaction process can be achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of mineralogy, geochemistry and chemical engineering, in particular to a device and method for in-situ study of mineral precipitation behavior in fluid mixing reaction process. BACKGROUND

[0002] In the fields of geological mineralization, oil and gas reservoir evolution, industrial water treatment, carbon capture and storage (CCUS) and corrosion science, the chemical reactions (such as neutralization, oxidation-reduction reaction) caused by the mixing of two or more fluids lead to the precipitation of minerals, which is a key core process. Such precipitation behavior directly controls the change of pore structure, the evolution of fluid permeability, the efficiency of chemical reaction and the durability of engineering materials. In the process of CO2 geological storage, mineral precipitation is the key mechanism to achieve long-term and stable storage. Therefore, in-situ, real-time and multi-scale observation of the process of fluid mixing induced mineral precipitation has important scientific significance and engineering value for understanding the dynamic mechanism, predicting the reaction path and final product, and optimizing the engineering parameters.

[0003] At present, the traditional non-in-situ sampling analysis research means in this field has many limitations, which cannot capture the dynamic information of the reaction process, and the sampling process can easily destroy the chemical equilibrium and spatial distribution of the system, introducing errors. There are flow cell devices in the prior art that use optical microscopes or high-speed cameras for in-situ observation. This kind of method can intuitively provide micrometer-scale two-dimensional information such as the morphology, size, number and spatial distribution of precipitated particles. However, its limitations are: weak penetration ability, unable to observe the reaction inside opaque or dark solution; limited resolution, difficult to detect nanoscale initial nucleation precursors, clusters or small particles; only morphological information can be obtained, and key data such as structural information cannot be obtained. Neutron scattering technology is a powerful tool for studying nanometer to micrometer scale structures, sensitive to light elements, and has excellent penetration ability, which can provide in-situ measurement of the bulk phase and statistics inside complex experimental devices, and provide information such as size distribution, morphology, number density and crystal structure of nanoscale particles. However, it cannot provide intuitive visual images and accurate spatial positioning information of particles.

[0004] Although optical observation and neutron scattering technology have strong complementarity in observation scale and information dimension, there is currently no in-situ monitoring device and method that can effectively integrate the two. The lack of comprehensive evolution information from nanoscale clusters to micrometer crystals leads to insufficient understanding of the whole process of mineral precipitation, making it difficult to establish a direct and accurate link between macroscopic phenomena and microscopic mechanisms.

[0005] In view of the above problems, the present application provides an optical observation and neutron scattering in-situ monitoring device and method for mineral precipitation behavior in a fluid mixing reaction process. This can cooperatively utilize the intuitive imaging advantage of optical observation and the high resolution and structure analysis advantage of neutron scattering, realize dynamic, continuous and multi-scale tracking of the whole process of fluid mixing-reaction-precipitation, and fill the gap of existing experimental devices and methods. SUMMARY

[0006] To solve the problems of in-situ mineral precipitation observation in the prior art and method, the present application provides an optical observation and neutron scattering in-situ monitoring device and method for mineral precipitation behavior in a fluid mixing reaction process. The application not only provides a new device coupling optical observation and neutron scattering monitoring, but also provides a new in-situ dynamic observation method, which will help to improve the deeper mechanism exploration and understanding of mineral precipitation behavior in various fields.

[0007] The technical scheme adopted by the present application is as follows: an optical observation and neutron scattering in-situ monitoring device for mineral precipitation behavior in fluid mixing, The device comprises an optical monitoring system, a neutron emission and detection device, a fluid injection and control system, a fluid mixing reaction device and a movable sample stage. The fluid mixing reaction device comprises a fluid mixing reaction kettle main body, front and rear sapphire visual windows and a sapphire wafer window cover plate. The front and rear of the fluid mixing reaction kettle main body are provided with sapphire visual windows for optical and neutron scattering observation. The left and right sides of the fluid mixing reaction kettle main body are each provided with two fixed screw ports to realize the connection and fixation of the reaction kettle and the fixed support, and then the reaction kettle is fixed on the movable optical platform. At least two fluid inlets and outlets are arranged on the upper side of the fluid mixing reaction kettle main body, and at least two fluid inlets and outlets are arranged on the lower side. Fluid is injected from one side of the inlet and outlet, and flows out from the other side of the inlet and outlet. The series of reactions in the counter-current mixing process of at least two fluids are realized by co-injection from the top and bottom. The optical monitoring system adopts a conventional microscopic detection device or a Raman detection device. The conventional microscopic detection device comprises a CCD camera with microscopic function and a backlight source. The light of the backlight source passes through the sapphire visual window of the fluid mixing reaction kettle to reach the microscopic CCD camera, and the signal is collected by a data acquisition and control computer. The Raman detection device comprises a laser, an optical CCD camera and a filter. The laser signal passes through the sapphire visual window of the fluid mixing reaction kettle to analyze the sample signal in the reaction kettle, and the frequency and intensity of the scattered light are collected. The signal is collected by a data acquisition and control computer, so as to obtain the chemical composition and structure information of the sample. The neutron emission and detection device includes a neutron scattering source, a fluid mixing reactor, and a neutron scattering signal detector; the light from the neutron scattering source passes through the sapphire viewing window of the fluid mixing reactor to reach the neutron scattering signal detector, and the signal is acquired by the data acquisition and control computer. In the fluid injection and control system, a multi-channel injection pump is connected to the fluid inlet on one side of the fluid mixing reactor via a high-pressure resistant pipeline. The injection pump is switched on and off and regulated by a data acquisition and control computer. A shut-off valve is installed on the injection pipeline to realize the injection and shut-off of the fluid in the pipeline. The fluid outlet on the other side of the fluid mixing reactor is connected to a vacuum pump and a waste liquid recovery cylinder via pipelines. A shut-off valve is installed on the outflow pipeline to control the opening and closing of the pipeline. In addition, a first tee connector and a second tee connector are installed on the outflow pipeline to realize the diversion of the fluid in the outflow pipeline.

[0008] Furthermore, the sealing structure on the main body of the fluid mixing reactor is achieved by sealing the reactor from all sides with corrosion-resistant polytetrafluoroethylene seals; the sapphire viewing window is fixed to the main body of the reactor in sequence through the front cover plate and the rear cover plate of the reactor, and the cover plate on each side is connected and fixed to the main body of the fluid mixing reactor by four fixing screws.

[0009] Furthermore, the upper side of the fluid mixing reactor body is provided with a first injection port, a spare injection port, and a second injection port in sequence to realize the mixed injection of two or three fluids; the lower side of the fluid mixing reactor is provided with a first outlet, a spare outlet, and a second outlet in sequence to realize the mixed outflow of two or three fluids.

[0010] Furthermore, in the fluid injection and control system, the multi-channel high-precision injection pump is connected to the fluid mixing reactor through the first injection pipeline and the second injection pipeline. The injection pump is switched on and off and adjusted by the data acquisition and control computer. The two ends of the pipeline are connected and sealed to the high-precision injection pump and the main body of the fluid mixing reactor through screw ferrule connectors, respectively. The injection pipeline is equipped with a first shut-off valve and a second shut-off valve to realize the injection and shut-off of fluid in the pipeline. The outlet end of the fluid mixing reactor is connected in sequence to the first outflow pipeline and the second outflow pipeline. The end of the outflow pipeline is connected to the vacuum pump and the first waste liquid recovery cylinder and the second waste liquid recovery cylinder, respectively. The outflow pipeline is equipped with a third stop valve, a fourth stop valve, a fifth stop valve and a sixth stop valve to control the opening and closing of the pipeline. In addition, the outflow pipeline is equipped with a first tee connector and a second tee connector to realize the diversion of the fluid in the outflow pipeline.

[0011] Furthermore, the fluid injection and control system is equipped with a backup injection port and a backup outlet, and a seventh shut-off valve and an eighth shut-off valve are installed on the backup pipeline to realize multi-channel fluid injection and mixing.

[0012] Furthermore, the sample stage installation includes a fluid mixing reactor fixed bracket and a movable optical platform; the fluid mixing reactor is connected to the reactor fixed bracket via lateral fixing screw holes, and the fixed bracket is fixed to the movable optical platform via corresponding screw holes, which facilitates installation on neutron scattering sample stages and other optical observation platforms.

[0013] Furthermore, the device features conventional microscopic detection mode, Raman detection mode, and in-situ neutron scattering observation mode. The conventional microscopic detection mode is as follows: S1. In the device assembly and sealing test stage, the connection of the pipelines in the entire system is completed; the high-pressure injection pump is electrically connected to the data acquisition and control computer to realize the control of injection. After the pipeline connection is completed, connect the fluid mixing reactor to the fluid mixing reactor fixing bracket, and then fix it on the movable optical platform 11; S2. Preparation of mineral precipitation samples: Saturate the entire pipeline with deionized water, close all shut-off valves in the entire pipeline system, and fill the syringe of the injection pump with the two mixed fluids to be reacted. S3. Connect the CCD camera with microscopic function to the data acquisition and control computer via the camera transmission cable; turn on the backlight, adjust the magnification of the CCD camera, and move the microscopic CCD camera back and forth until it is focused on the sapphire viewing window. S4. Set the high-precision injection pump to the target flow rate, and after turning on the high-precision injection pump, simultaneously open the first and second shut-off valves to ensure that the two fluids enter the main body of the fluid mixing reactor at the same time to undergo a mixing reaction. S5. At the same time, open the third and sixth shut-off valves, and the reaction waste liquid flowing out of the main body of the fluid mixing reactor enters the first and second waste liquid recovery cylinders; other shut-off valves in the pipeline remain closed until the observation is completed. Raman detection mode, specifically: S1. In the device assembly and sealing test stage, the connection of the pipelines in the entire system is completed; the high-pressure injection pump is electrically connected to the data acquisition and control computer to realize the control of injection. After the pipeline connection is completed, connect the fluid mixing reactor to the fluid mixing reactor fixing bracket, and then fix it on the movable optical platform 11; S2. Preparation of mineral precipitation samples: Saturate the entire pipeline with deionized water, close all shut-off valves in the entire pipeline system, and fill the syringe of the injection pump with the two mixed fluids to be reacted. S3. Connect the Raman laser and optical CCD camera to the data acquisition and control computer via a transmission line; adjust the excitation of visible light and laser through filters; adjust the magnification of the CCD camera and focus it to determine the sample area to be observed; switch to laser mode to acquire Raman scattering signals. S4. Set the high-precision injection pump to the target flow rate, and after turning on the high-precision injection pump, simultaneously open the first and second shut-off valves to ensure that the two fluids enter the main body of the fluid mixing reactor at the same time to undergo a mixing reaction. S5. At the same time, open the third and sixth shut-off valves, and the reaction waste liquid flowing out of the main body of the fluid mixing reactor enters the first and second waste liquid recovery cylinders; other shut-off valves in the pipeline remain closed until the observation is completed. The in-situ observation mode for neutron scattering is as follows: S1. In the device assembly and sealing test stage, the connection of the pipelines in the entire system is completed; the high-pressure injection pump is electrically connected to the data acquisition and control computer to realize the control of injection. After the pipeline connection is completed, connect the fluid mixing reactor to the fluid mixing reactor fixing bracket, and then fix it on the movable optical platform 11; S2. Preparation of mineral precipitation samples: Saturate the entire pipeline with deionized water, close all shut-off valves in the entire pipeline system, and fill the syringe of the injection pump with the two mixed fluids to be reacted. S3. Replace all shut-off valves with electronic shut-off valves that can be remotely opened and closed via a data acquisition and control computer; switch different chopper operating modes to switch different wavelength bandwidths, adjust the distance between the neutron scattering detector and the sample, and select the collimation length according to the required Q range. S4. After adjusting the neutron scattering observation parameters, establish a cyclic acquisition sequence and collect data at fixed intervals. Remotely set the target flow rate of the high-precision injection pump through the data acquisition and control computer. After the injection pump is turned on, simultaneously open the first and second shut-off valves remotely to ensure that the two fluids can enter the fluid mixing reactor at the same time to undergo a mixing reaction. S5. At the same time, remotely open the third and sixth shut-off valves to ensure that the reaction waste liquid flowing out of the fluid mixing reactor enters the first waste liquid recovery cylinder (15) and the second waste liquid recovery cylinder (21); other shut-off valves in the pipeline remain closed. S6. Simultaneously start the established neutron scattering data acquisition sequence until the neutron scattering signal no longer changes, indicating that the reaction has completely ended.

[0014] Furthermore, in the in-situ neutron scattering observation mode, the deionized water in the solution used is replaced with deuterated water.

[0015] The beneficial effects of this invention are: it enables the coupled use of multiple characterization methods using a single device. This invention integrates conventional microscopic optical observation, Raman spectroscopy analysis, and neutron scattering detection in situ and in real time. Microscopic optical imaging can directly capture the macroscopic morphology, spatial distribution, crystal growth rate, and fluid mixing interface dynamics of mineral precipitation. Raman spectroscopy can provide precise identification of the structure, chemical composition, and crystal phase type of precipitates within the same micro-region. Neutron scattering can non-destructively detect precursor clusters, nucleation processes, and particle aggregation behavior at the nanometer to micrometer scale in solution. This invention establishes a direct causal link from molecular structure to nanoscale cluster evolution, and then to macroscopic morphology, enabling direct empirical observation of the "nucleation" black box process and completely solving the problems of information distortion and lack of correlation caused by traditional non-in-situ observations. This device not only significantly improves experimental efficiency and reduces experimental costs, but also provides key experimental methods and data support for a deeper understanding of precipitation mechanisms and accurate prediction of mineral deposit formation, geological preservation, and environmental pollutant migration. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a microscopic optical observation device and method for observing the precipitation behavior of minerals during a fluid mixing reaction.

[0017] Figure 2 This is a schematic diagram of a Raman optical observation device and method for observing the precipitation behavior of minerals during a fluid mixing reaction.

[0018] Figure 3 This is a schematic diagram of an in-situ neutron scattering monitoring device and method for monitoring mineral precipitation behavior during a fluid mixing reaction.

[0019] Figure 4 This is a three-dimensional view of a fluid mixing reactor.

[0020] Figure 5 This is the front view of the fluid mixing reactor.

[0021] Figure 6 This is a top view of a fluid mixing reactor.

[0022] Figure 7 This is a cross-sectional view of a fluid mixing reactor.

[0023] In the diagram: 1. Fluid mixing reactor; 2. Neutron scattering light source; 3. Neutron scattering signal detector; 4. High-precision injection pump; 5. Data acquisition and control computer; 6. First shut-off valve; 7. First injection line; 8. Second shut-off valve; 9. Second injection line; 10. Fluid mixing reactor fixed support; 11. Movable optical platform; 12. First outflow line; 13. First tee connector; 14. Third shut-off valve; 15. First waste liquid recovery cylinder; 16. Fourth shut-off valve; 17. Second outflow line; 18. Second tee connector; 19. Fifth shut-off valve; 20. Sixth shut-off valve; 21. Second waste liquid recovery cylinder; 22. Vacuum pump; 23. Microscopic CCD camera; 24. Backlight; 25. Backup injection port; 26. Seventh shut-off valve; 27. Backup outlet; 28. Eighth shut-off valve; 29. ​​Laser; 30. Optical CCD camera; 31. Filter.

[0024] 1a. Main body of the fluid mixing reactor; 1b. Front cover plate of the reactor; 1c. Rear cover plate of the reactor; 1d. Cover plate fixing screws; 1e. Sapphire viewing window; 1f. Sealing structure; 1g. First injection port; 1h. Backup injection port; 1i. Second injection port; 1j. First outlet; 1k. Backup outlet; 1l. Second outlet; 1m. Reactor fixing screw port. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0026] Figures 1 to 3 The device and method for optical observation and in-situ monitoring of mineral precipitation behavior during fluid mixing reaction are presented in sequence. The device includes a conventional optical microscopy observation system, a Raman monitoring system, a neutron emission and detection device, a fluid injection and control system, a fluid mixing reaction device, and a sample stage for installation.

[0027] The fluid mixing reaction apparatus comprises a fluid mixing reactor body, sapphire wafer windows at the front and rear of the reactor, sapphire wafer window covers at the front and rear of the reactor, seals, and fixing screws.

[0028] The main body 1a of the fluid mixing reactor is made of 316L stainless steel and includes sapphire viewing windows 1e at the front and rear of the reactor body, corrosion-resistant polytetrafluoroethylene sealing structure 1f, front cover plate 1b, rear cover plate 1c, cover plate fixing screws 1d, and fluid mixing reactor body fixing screw holes 1m.

[0029] The fluid mixing reactor is provided with a first injection port 1g, a spare injection port 1h, and a second injection port 1i on the upper side; the fluid mixing reactor is also provided with a first outlet 1j, a spare outlet 1k, and a second outlet 1l on the upper side.

[0030] The fluid injection and control system includes a multi-channel high-precision injection pump 4, a high-pressure resistant first injection line and a second injection line 9, a control computer 5, a first outflow line 12 and a second outflow line 17, a vacuum pump 22, a first waste liquid recovery cylinder 15, a second waste liquid recovery cylinder 21, a spare injection port 25, and a spare outlet 27. The injection line is equipped with a first shut-off valve 6 and a second shut-off valve 8, and the outflow line is equipped with a third shut-off valve 13, a fourth shut-off valve 16, a fifth shut-off valve 19, and a sixth shut-off valve 20. In addition, the outflow line is equipped with a first tee connector 13 and a second tee connector 18. The spare line is equipped with a seventh shut-off valve 26 and an eighth shut-off valve 28. The inlet and outlet can be used interchangeably, which can realize multiple flow mixing modes of various fluids, including co-current and counter-current flow.

[0031] The optical monitoring system includes a CCD camera 23 with microscopic function, a backlight 24, and an image data acquisition computer 5. In addition to conventional microscopic imaging, other optical characterization methods such as Raman spectroscopy are also applicable to this device, including a laser 29, an optical CCD camera 30, and a filter 31. This enables the detection of mineral precipitates generated during fluid mixing reactions. By coupling Raman spectral signals and optical microscopic images, a unified observation of mineral phases and microscopic mineral morphology can be achieved.

[0032] The neutron emission and detection device includes a neutron scattering source 2, a neutron scattering signal detector 3, and a neutron scattering data acquisition and analysis computer 5. The neutron scattering monitoring method can observe smaller-scale particle size characteristics that are difficult to observe with conventional optical imaging, and has the advantage of large field of view observation. By coupling neutron scattering signals and Raman spectral signals, the size characteristics and mineral phase characteristics of certain pre-nucleated clusters can be detected, and the changes in the dynamic process of mineral nucleation and growth can be deeply analyzed. The visualization window material on the fluid mixing reactor is made of C-axis sapphire, which can minimize the influence of the window material on the neutron scattering signal, and its high transparency will also reduce the interference to the optical signal.

[0033] The sample stage installation includes a fluid mixing reactor fixed bracket 10 and a movable optical platform 11. The fluid mixing reaction device 1 is connected to the reactor fixed bracket 10 through a lateral fixing screw hole 1m. The fixed bracket is fixed to the movable optical platform 11 through corresponding screw holes. The movable optical platform is easy to install on the neutron scattering sample stage and other optical observation platforms.

[0034] The aforementioned optical observation and neutron scattering in-situ monitoring device for mineral precipitation behavior during fluid mixing and reaction processes is applied to the observation of the entire process of mineral nucleation and growth during fluid mixing-reaction-precipitation. Its general working process is divided into two stages according to the time sequence: device assembly and sealing test, and fluid mixing and precipitation observation. The specific implementation method is as follows: Example 1

[0035] Taking the optical observation of the nucleation and growth process of mineral precipitate particles as an example, the specific implementation plan is as follows (e.g. Figure 1 (as shown) In the device assembly and sealing test phase, the first step is to connect the pipelines throughout the system, connecting the fluid mixing reactor 1, high-precision injection pump 4, first shut-off valve 6, first injection pipeline 7, second shut-off valve 8, second injection pipeline 9, first outflow pipeline 12, first tee connector 13, third shut-off valve 14, first waste liquid recovery cylinder 15, fourth shut-off valve 16, second outflow pipeline 17, second tee connector 18, fifth shut-off valve 19, sixth shut-off valve 20, second waste liquid recovery cylinder 21, vacuum pump 22, spare injection port 25, seventh shut-off valve 26, spare outlet 27, and eighth shut-off valve 28 together. The high-precision injection pump 4 is connected to the data acquisition and control computer 5 via a data connection cable, thereby enabling high-precision injection control.

[0036] After the pipeline connection is completed, the fluid mixing reactor is connected to the fluid mixing reactor fixing bracket 10, and then fixed on the optical platform 11.

[0037] Specifically, the installation steps of the fluid mixing reactor 1 are as follows: The sapphire viewing window 1e is cleaned and dried to prevent dust adhering to the window from interfering with optical observation. The sapphire viewing window 1e is fixed to the main body 1a of the fluid mixing reactor, and the two are sealed together by a sealing structure 1f, using a corrosion-resistant polytetrafluoroethylene (PTFE) sealing ring. The front and rear sapphire viewing windows are sequentially pressed and installed using the reactor front cover plate 1b and the reactor rear cover plate 1c, with each side secured by cover plate fixing screws 1d. The first injection line 7, the second injection line 9, the first outflow line 12, the second outflow line 17, the spare injection port 25, and the spare outflow port 27 are sequentially connected to the first injection port 1g, the second injection port 1i, the first outflow port 1j, the second outflow port 1l, the spare injection port 1h, and the spare outflow port 1k.

[0038] After installation, close the first shut-off valve 6, the second shut-off valve 8, the third shut-off valve 14, and the sixth shut-off valve 20, and open the other shut-off valves to keep the pipeline unobstructed. Use vacuum pump 22 to pump the entire... If there is no change, it proves that the system is well sealed, and the next process can be continued; if there is a change, use leak detection to check all the connections of the system until the pipeline can maintain a vacuum environment for a long time.

[0039] In the mineral precipitation sample preparation and observation stage, the entire pipeline was first saturated with deionized water, all shut-off valves in the entire pipeline system were closed, and the syringe of the high-precision injection pump 4 was filled with the two mixed fluids to be reacted. Then, the CCD camera 23 with microscopic function was connected to the data acquisition computer 5 via the camera transmission cable. The backlight 24 was turned on, the magnification of the CCD camera 23 was adjusted, and the CCD camera was moved back and forth until it was focused on the viewing window of the reaction vessel. To ensure successful observation of the fluid mixing and mineral precipitation process, the CCD camera was adjusted to be aligned with the center of the sapphire viewing window before the experiment began.

[0040] The specific observation process is as follows: Set the high-precision injection pump 4 to the target flow rate, and after the injection pump is turned on, simultaneously open the first shut-off valve 6 and the second shut-off valve 8 to ensure that the two fluids can enter the reactor at the same time to undergo a mixing reaction; at the same time, open the third shut-off valve 14 and the sixth shut-off valve 20 to ensure that the reaction waste liquid flowing out of the reactor enters the first waste liquid recovery cylinder 15 and the second waste liquid recovery cylinder 21; other shut-off valves in the pipeline remain closed.

[0041] After the observation is completed, dilute hydrochloric acid solution and deionized water are injected into the pipeline in sequence to clean the pipeline. The fluid mixing reactor 1 can be disassembled separately for cleaning and drying. Example 2

[0042] In addition to conventional microscopic imaging, other optical characterization techniques such as Raman spectroscopy are also applicable to this device. This enables the detection of mineral precipitates generated during fluid mixing reactions. By coupling Raman spectral signals and optical microscopic images, it is possible to further achieve unified observation of mineral phases and microscopic mineral morphology.

[0043] Raman detection methods (such as) Figure 2 As shown), the details are as follows: S1. In the device assembly and sealing test stage, the connection of the pipeline in the whole system is completed; the high injection pump 4 is electrically connected to the data acquisition and control computer 5 to realize the injection control; after the pipeline connection is completed, the fluid mixing reactor 1 is connected to the fluid mixing reactor fixed bracket 10, and then fixed on the movable optical platform 11. S2. Preparation of mineral precipitation samples: Saturate the entire pipeline with deionized water, close all shut-off valves in the entire pipeline system, and fill the syringe of injection pump 4 with the two mixed fluids to be reacted. S3. Connect the Raman laser 29 and the optical CCD camera 30 to the data acquisition and control computer 5 via a transmission line; adjust the excitation of visible light and laser through the filter 31; adjust the magnification of the CCD camera 29 and focus it to determine the sample area to be observed; switch to laser mode to acquire Raman scattering signals. S4. Set the high-precision injection pump 4 to the target flow rate. After turning on the high-precision injection pump 4, simultaneously open the first shut-off valve 6 and the second shut-off valve 8 to ensure that the two fluids enter the fluid mixing reactor body 1a at the same time to undergo a mixing reaction. S5. At the same time, open the third shut-off valve 14 and the sixth shut-off valve 20, and the reaction waste liquid flowing out of the fluid mixing reactor body 1a enters the first waste liquid recovery cylinder 15 and the second waste liquid recovery cylinder 21; other shut-off valves in the pipeline remain closed until the observation is completed.

[0044] In the mineral precipitation sample preparation and observation stages, Raman detection is similar to the mineral precipitation process during fluid mixing in conventional microscopic optical observation. The main differences are threefold: First, stainless steel plates are used when Raman detecting the growth structure and mineral phases of mineral precipitation particles, whereas a light source is required in microscopic optical observation. The stainless steel plates prevent the Raman laser from penetrating the mineral precipitation crystal particles in the solution. Second, during Raman detection, the movable optical platform 11 needs to be fixed to the existing optical platform observation stage of the laboratory Raman equipment to ensure system stability. Third, during Raman detection, the Raman equipment's built-in optical CCD camera 30 is primarily used to capture and acquire Raman spectra of the mineral precipitation crystal structure. Example 3

[0045] Taking the in-situ observation of the nucleation and growth process of mineral precipitate particles by neutron scattering as an example, the specific implementation plan is as follows (e.g. Figure 3 (as shown) In the device assembly and sealing test phases, the implementation plan is exactly the same as that for optical observation of the nucleation and growth process of mineral precipitate particles.

[0046] In the preparation and observation of mineral precipitates in fluid mixing: neutron scattering can detect the morphological characteristics of smaller particles, which is crucial for understanding the comprehensive evolution from nanoclusters to micron-sized crystals. This process often occurs in the early stages of the mixing reaction, thus capturing this dynamic process is highly time-constrained. Furthermore, due to the prohibition of personnel remaining in the neutron scattering environment during the experiment, remote, instantaneous control of the entire system is required.

[0047] The specific details of the observation process are as follows: The entire apparatus is fixed on the neutron scattering sample stage. During the mineral precipitation sample preparation and observation process, the entire pipeline is first saturated with deionized water, all shut-off valves in the entire pipeline system are closed, and the syringe of the high-precision injection pump 4 is filled with the two mixed fluids to be reacted. The first shut-off valve 6, the second shut-off valve 8, the third shut-off valve 14, and the sixth shut-off valve 20 are replaced with electronic shut-off valves that can be remotely opened and closed by the control computer 5. All experimental personnel evacuate the neutron scattering sample environment chamber to the control room. Different chopper operating modes are switched to switch different wavelength bandwidths, and the distance from the neutron scattering detector 3 to the sample is adjusted. The collimation length is selected according to the required Q range; the shorter the collimation length, the greater the neutron flux, but the larger the minimum achievable Q. After adjusting the neutron scattering observation parameters, a cyclic acquisition sequence is established, and data is collected at fixed intervals. The high-precision injection pump 4 is remotely set to the target flow rate via the control computer 5. After the injection pump is started, the first shut-off valve 6 and the second shut-off valve 8 are simultaneously opened remotely to ensure that the two fluids can enter the reactor simultaneously for mixing and reaction. At the same time, the third shut-off valve 14 and the sixth shut-off valve 20 are remotely opened to ensure that the reaction waste liquid flowing out of the reactor enters the first waste liquid recovery cylinder 15 and the second waste liquid recovery cylinder 21. Other shut-off valves in the pipeline remain closed. The established neutron scattering data acquisition sequence is simultaneously activated.

[0048] The reaction can be considered complete when the neutron scattering signal stops changing. Laboratory personnel can then enter the neutron scattering sample chamber to process the samples, sequentially injecting dilute hydrochloric acid and deionized water into the pipelines for cleaning. The fluid mixing reactor 1 can be disassembled separately for cleaning and drying. When observing mineral precipitation characteristics during the fluid mixing process using neutron scattering, the deionized water in the solution is replaced with deuterated water. This is mainly because deuterated water has a positive scattering length and a very small incoherent scattering cross section, which can significantly reduce the interference of background noise on neutron scattering monitoring.

[0049] Furthermore, the fluid mixing reactor body of this invention is equipped with spare inlet and outlet ports, enabling experimental functions that are not limited to two fluids and mixing reaction processes. In addition, all components in this device are made of high-pressure resistant and corrosion-resistant materials, thus enabling extreme gas-liquid and liquid-liquid mixing reactions.

[0050] The above-described embodiments are merely for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made based on the substance of the content of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An in-situ monitoring device for mineral precipitation behavior during fluid mixing and reaction, characterized in that: The device includes a fluid injection and control system, a fluid mixing and reaction device (1), a movable sample stage, and an in-situ detection system; The fluid mixing reaction device (1) includes a fluid mixing reaction vessel body, sapphire viewing windows at the front and rear of the reaction vessel, and a sapphire wafer window cover plate; The fluid mixing reactor body (1a) is equipped with sapphire viewing windows (1e) at the front and rear for optical and neutron scattering observation; two fixing screw holes (1m) are provided on the left and right sides of the fluid mixing reactor body (1a) to realize the connection and fixation of the reactor to the fixed support, thereby fixing the entire reactor system on the movable optical platform (11). The fluid mixing reactor body (1a) is provided with at least two fluid inlets and outlets on the upper side and at least two fluid inlets and outlets on the lower side respectively; fluid is injected from one inlet and outlet and flows out from the other inlet and outlet; the upper and lower co-injection simulates a series of reactions in the countercurrent mixing process of at least two fluids; The multi-channel injection pump (4) in the fluid injection and control system is connected to the fluid inlet on one side of the fluid mixing reactor (1) through a high-pressure resistant pipeline. The injection pump (4) is switched on and off and adjusted by the data acquisition and control computer (5). A shut-off valve is provided on the injection pipeline to realize the injection and shut-off of the fluid in the pipeline. The fluid outlet on the other side of the fluid mixing reactor (1) is connected to the vacuum pump and waste liquid recovery cylinder through a pipeline. A shut-off valve is provided on the outflow pipeline to control the opening and closing of the pipeline. In addition, a first tee connector (13) and a second tee connector (18) are provided on the outflow pipeline to realize the diversion of the fluid in the outflow pipeline. The in-situ detection system is a microscopic optical detection device, a Raman detection device, or a neutron emission and detection device; The microscopic detection device includes a CCD camera (23) with microscopic function and a backlight (24); the light from the backlight (24) passes through the sapphire viewing window (1e) of the fluid mixing reactor (1) to reach the microscopic CCD camera (23), and the signal is collected by the data acquisition and control computer (5). The Raman detection device includes a laser (29), an optical CCD camera (30), and a filter (31); the laser signal passes through the sapphire viewing window (1e) of the fluid mixing reactor (1) to analyze the sample signal inside the reactor, collect the frequency and intensity of the scattered light, and the data acquisition and control computer (5) collects the signal to obtain the chemical composition and structural information of the sample; The neutron emission and detection device includes a neutron scattering light source (2), a fluid mixing reactor (1), and a neutron scattering signal detector (3); the light from the neutron scattering light source (2) passes through the sapphire viewing window (1e) of the fluid mixing reactor (1) and reaches the neutron scattering signal detector (3), and the signal is collected by the data acquisition and control computer (5).

2. The apparatus according to claim 1, characterized in that: The sealing structure (1f) on the fluid mixing reactor body (1a) is used to seal the reactor from all sides by a corrosion-resistant polytetrafluoroethylene seal; the sapphire viewing window (1e) is assembled with the reactor body through the reactor front cover plate (1b) and reactor rear cover plate (1c) in sequence, and the cover plate on each side is connected and fixed to the fluid mixing reactor body (1a) by four fixing screws (1d).

3. The apparatus according to claim 2, characterized in that: The fluid mixing reactor body (1a) is provided with a first injection port (1g), a spare injection port (1h), and a second injection port (1i) on the upper side to realize the mixed injection of two or three fluids; the fluid mixing reactor body is provided with a first outlet (1j), a spare outlet (1k), and a second outlet (1l) on the lower side to realize the mixed outflow of two or three fluids.

4. The apparatus according to claim 1, characterized in that: In the fluid injection and control system, the multi-channel high-precision injection pump (4) is connected to the fluid mixing reactor (1) through the first injection pipeline (7) and the second injection pipeline (9). The injection pump is switched on and off and adjusted by the data acquisition and control computer (5). The two ends of the pipeline are connected and sealed to the high-precision injection pump (4) and the main body of the fluid mixing reactor (1a) respectively through screw ferrule connectors. The injection pipeline is equipped with a first shut-off valve (6) and a second shut-off valve (8) to realize the injection and shut-off of fluid in the pipeline. The outlet end of the fluid mixing reactor is connected in sequence to the first outflow pipe (12) and the second outflow pipe (17). The end of the outflow pipe is connected to the vacuum pump (22) and the first waste liquid recovery cylinder (15) and the second waste liquid recovery cylinder (21), respectively. The outflow pipe is equipped with a third shut-off valve (13), a fourth shut-off valve (16), a fifth shut-off valve (19), and a sixth shut-off valve (20) to control the opening and closing of the pipe. In addition, the outflow pipe is equipped with a first tee connector (13) and a second tee connector (18) to realize the diversion of fluid in the outflow pipe.

5. The apparatus according to claim 4, characterized in that: The fluid injection and control system is equipped with a backup injection port (25) and a backup outlet (27), and a seventh shut-off valve (26) and an eighth shut-off valve (28) are installed on the backup pipeline to realize multi-channel fluid injection and mixing.

6. The apparatus according to claim 5, characterized in that: The sample stage installation includes a fluid mixing reactor fixed bracket (10) and a movable optical platform (11); the fluid mixing reaction device (1) is connected to the reactor fixed bracket (10) through a lateral fixing screw hole (1m), and the fixed bracket is fixed to the movable optical platform (11) through the corresponding screw hole. The movable optical platform is easy to install on the neutron scattering sample stage and the optical observation platform.

7. The method of operating the device according to claim 6, characterized in that, The device features conventional microscopic detection modes, specifically: S1. In the assembly and sealing test of the device, the connection of the pipeline in the whole system is completed; the high injection pump (4) is electrically connected to the data acquisition and control computer (5) to realize the injection control; after the pipeline connection is completed, the fluid mixing reactor (1) is connected to the fluid mixing reactor fixed bracket (10) and then fixed on the movable optical platform 11. S2, mineral precipitation sample preparation, saturate the entire pipeline with deionized water, close all shut-off valves in the entire pipeline system, and fill the syringe of the injection pump (4) with the two mixed fluids to be reacted. S3. Connect the micro CCD camera (23) to the data acquisition and control computer (5) via the camera transmission line; turn on the backlight (24), adjust the magnification of the CCD camera (23), and move the micro CCD camera (23) back and forth until it is focused on the sapphire viewing window (1e). S4. Set the target flow rate of the high-precision injection pump (4), and after turning on the high-precision injection pump (4), simultaneously open the first shut-off valve (6) and the second shut-off valve (8) to ensure that the two fluids enter the main body (1a) of the fluid mixing reactor at the same time to carry out the mixing reaction. S5. At the same time, the third shut-off valve (14) and the sixth shut-off valve (20) are opened, and the reaction waste liquid flowing out of the fluid mixing reactor body (1a) enters the first waste liquid recovery cylinder (15) and the second waste liquid recovery cylinder (21); other shut-off valves in the pipeline remain closed until the observation is completed.

8. The method of operating the device according to claim 6, characterized in that, The device features a Raman detection mode, specifically: S1. In the assembly and sealing test of the device, the connection of the pipeline in the whole system is completed; the high injection pump (4) is electrically connected to the data acquisition and control computer (5) to realize the injection control; after the pipeline connection is completed, the fluid mixing reactor (1) is connected to the fluid mixing reactor fixed bracket (10) and then fixed on the movable optical platform 11. S2, mineral precipitation sample preparation, saturate the entire pipeline with deionized water, close all shut-off valves in the entire pipeline system, and fill the syringe of the injection pump (4) with the two mixed fluids to be reacted. S3. Connect the Raman laser (29) and the optical CCD camera (30) to the data acquisition and control computer (5) via a transmission line; adjust the excitation of visible light and laser through the filter (31); adjust the magnification of the CCD camera (29) and focus it to determine the sample area to be observed; switch to laser mode to collect Raman scattering signals. S4. Set the target flow rate of the high-precision injection pump (4), and after turning on the high-precision injection pump (4), simultaneously open the first shut-off valve (6) and the second shut-off valve (8) to ensure that the two fluids enter the main body (1a) of the fluid mixing reactor at the same time to carry out the mixing reaction. S5. At the same time, the third shut-off valve (14) and the sixth shut-off valve (20) are opened, and the reaction waste liquid flowing out of the fluid mixing reactor body (1a) enters the first waste liquid recovery cylinder (15) and the second waste liquid recovery cylinder (21); other shut-off valves in the pipeline remain closed until the observation is completed.

9. The method of operating the device according to claim 6, characterized in that, The device features an in-situ neutron scattering observation mode, specifically: S1. In the assembly and sealing test of the device, the connection of the pipeline in the whole system is completed; the high injection pump (4) is electrically connected to the data acquisition and control computer (5) to realize the injection control; after the pipeline connection is completed, the fluid mixing reactor (1) is connected to the fluid mixing reactor fixed bracket (10) and then fixed on the movable optical platform 11. S2, mineral precipitation sample preparation, saturate the entire pipeline with deionized water, close all shut-off valves in the entire pipeline system, and fill the syringe of the injection pump (4) with the two mixed fluids to be reacted. S3. Replace all shut-off valves with electronic shut-off valves that can be remotely opened and closed by the data acquisition and control computer (5); switch different chopper operating modes to switch different wavelength bandwidths, adjust the distance from the neutron scattering detector (3) to the sample, and select the collimation length according to the required Q range. S4. After adjusting the neutron scattering observation parameters, establish a cyclic acquisition sequence and collect data at fixed intervals. The high-precision injection pump (4) is remotely set to the target flow rate through the data acquisition and control computer (5). After the injection pump is turned on, the first shut-off valve (6) and the second shut-off valve (8) are opened remotely to ensure that the two fluids can enter the fluid mixing reactor (1) at the same time to undergo a mixing reaction. S5. At the same time, remotely open the third shut-off valve (14) and the sixth shut-off valve (20) to ensure that the reaction waste liquid flowing out of the fluid mixing reactor (1) enters the first waste liquid recovery cylinder (15) and the second waste liquid recovery cylinder (21); other shut-off valves in the pipeline remain closed. S6. Simultaneously start the established neutron scattering data acquisition sequence until the neutron scattering signal no longer changes, indicating that the reaction has completely ended.

10. The method of operating the device according to claim 9, characterized in that, In the in-situ neutron scattering observation mode, the deionized water in the solution is replaced with deuterated water.

Images