Preparation method of uranium mineral corrosion online monitoring experiment sample and experiment method

Abstract

The invention relates to a preparation method of an online monitoring experimental sample for uranium mineral corrosion and an experimental method. According to the preparation method of the uranium mineral corrosion on-line monitoring experiment sample, a rock sample is placed in a visual groove, the visual groove is made of a transparent material, and the bottom of the visual groove is a plane. And the visual groove is made of transparent glass. A visual cover plate is arranged on the rock sample, the visual cover plate is made of a transparent material, and the edge of the visual cover plate is bonded and fixed with the edge of the visual groove. The visual cover plate is made of transparent glass. According to the preparation method of the uranium ore corrosion on-line monitoring experiment sample, the core step of improving the uranium ore corrosion in-situ monitoring technology is optimized by preparing the water-rock reaction visualization experiment device, and then the preparation method serves research and development of the uranium ore corrosion in-situ monitoring technology.

Description

Technical Field

[0001] This application belongs to the technical field of uranium ore development, and particularly relates to a method for preparing an experimental sample for on-line monitoring of uranium mineral dissolution and an experimental method. Background Art

[0002] The study of the reaction law of uranium minerals in different production states during the CO2+O2 leaching process is of great significance for optimizing the in-situ leaching process. Conventional experiments, including stirring leaching tests, column leaching tests, and pressure leaching tests, etc., cannot directly monitor the dynamic change details of the uranium mineral-leaching agent dissolution reaction. There is an urgent need to develop an in-situ monitoring technology for uranium mineral dissolution during the leaching process. Conducting in-situ on-line monitoring of the dissolution reaction of uranium minerals with different occurrences and leaching agents in sandstone-type uranium ore deposits can more intuitively reveal the reaction characteristics of different occurrences of uranium during the leaching process and the migration laws of various elements, master the response characteristics of different uranium minerals to leaching conditions, obtain the optimal leaching parameters for different occurrences of uranium minerals, construct a uranium mineral leaching process database, and thus realize the optimization and popularization application of the CO2+O2 leaching process. However, due to the generally small size of uranium minerals in sandstone-type uranium deposits, most of them are below 50um, and their distribution in the ore body is extremely uneven, which poses great challenges in sample preparation during the research and development of in-situ monitoring technology for uranium mineral dissolution: not only the microscopic morphology of uranium minerals needs to be observed in real time, but also the components of the leaching solution and the changes in the flow field can be monitored on-line. Therefore, the core of the in-situ monitoring technology for uranium mineral dissolution lies in sample production. Summary of the Invention

[0003] Aiming at the above problems, the purpose of this application is to provide a method for preparing an experimental sample for on-line monitoring of uranium mineral dissolution and an experimental method to serve the in-situ monitoring technology for uranium mineral dissolution during the leaching process.

[0004] To achieve the above purpose, this application adopts the following technical solutions:

[0005] A method for preparing an experimental sample for on-line monitoring of uranium mineral dissolution, by setting a visualization groove to place the rock sample, the visualization groove is made of transparent material, and its bottom is a plane.

[0006] Preferably, the material of the visualization groove is transparent glass.

[0007] Preferably, a visualization cover plate is arranged on the rock sample, the visualization cover plate is made of transparent material, and its edge is adhesively fixed to the edge of the visualization groove.

[0008] Preferably, the material of the visualization cover plate is transparent glass.

[0009] Preferably, epoxy resin glue is evenly coated on the edge of the visualization cover plate or the visualization groove, and the two are adhesively fixed.

[0010] An on-line monitoring experimental method for uranium mineral dissolution, including the preparation method of the on-line monitoring experimental sample for uranium mineral dissolution described above.

[0011] Preferably, the experimental method includes the following steps:

[0012] (1) Sample collection and sampling;

[0013] (2) Rock and ore section preparation: Select samples from the ore-bearing zone, grind them into thin sections, and make inclusion sections with a thickness of 3 - 5 mm;

[0014] (3) Select the target observation area, cut and dissolve the colloid to obtain the rock sample;

[0015] (4) Prepare the visualization groove, fix the rock sample, and install the visualization groove in the high-pressure chamber;

[0016] (5) Conduct on-line monitoring and analysis of uranium mineral dissolution.

[0017] Preferably, the process of selecting the target observation area in step (3) includes selecting the target mineral through a scanning electron microscope, photographing the morphology of the area where the target mineral is located and the surrounding minerals, debris, etc., and recording the morphological characteristics before the reaction; finding the target mineral under a polarized light microscope, taking pictures and marking the position of the target mineral; after determining the marked position, clean the surface and polish the inclusion section.

[0018] Preferably, in the colloid dissolution process of step (3), dichloromethane is used to dissolve the colloid and other impurities.

[0019] Preferably, the process of preparing the visualization groove in step (4) includes designing the size of the visualization groove according to the rock sample, and laser engraving to obtain the visualization groove.

[0020] This application has the following advantages:

[0021] The preparation method of the on-line monitoring experimental sample for uranium mineral dissolution in this application optimizes the core steps of improving the in-situ monitoring technology of uranium mineral dissolution by preparing an experimental device for visualizing the water-rock reaction. It can directly observe the microscopic dissolution morphology of the uranium mineral surface and the morphological changes during the reaction process / different reaction stages, avoid the reaction interruption and sample damage caused by traditional sampling analysis, ensure the stability of the observation object, and thus serve the in-situ monitoring technology of uranium mineral dissolution. This application is particularly suitable for application in the CO2 + O2 leaching process.

[0022] The experimental method of this application can conduct in-situ monitoring of uranium mineral dissolution, realize real-time observation of the microscopic morphology of uranium minerals and on-line monitoring of the components of the leaching solution, flow field changes, etc. It is particularly suitable for application in the CO2 + O2 leaching process and can also be used in the acid leaching process. Description of the Drawings

[0023] Figure 1 It is a technical roadmap for preparing experimental samples for on-line monitoring in Example 1;

[0024] Figure 2 It is a schematic diagram of the production process of a water-rock reaction visualization rock and mineral thin plate in Example 1;

[0025] Figure 3 It is a photo of the visualization rock and mineral thin plate in Example 1;

[0026] Figure 4 It is a photo of the sample visualized under a microscope during the in-situ monitoring experiment in Example 1;

[0027] Figure 5 It is a comparison diagram of the morphological characteristics of carbonate cements in the sample before and after the experiment in Example 1. Detailed Description of the Invention

[0028] The present application will be described in detail below in conjunction with the drawings and embodiments.

[0029] An on-line monitoring experiment method for uranium mineral dissolution includes the following steps:

[0030] (1) Sample collection and sampling. The specific process includes core sampling in the ore-bearing section, including collection of borehole data, field core observation, field core logging, and field core sampling.

[0031] (2) Rock and mineral section preparation: Select samples from the ore-bearing zone, grind them into inclusion sections with a thickness of 3-5 mm.

[0032] (3) Select the target observation area, cut and dissolve the glue to obtain a rock sample.

[0033] The specific process includes selecting the target mineral through a scanning electron microscope, performing point, line, and surface scans on the target observation area, photographing the morphology of the area where the target mineral is located and the surrounding minerals, debris, etc., and recording the morphological characteristics before the reaction; finding the target mineral under a polarized light microscope, taking a photo and marking the position of the target mineral; after determining the marked position, clean the surface and polish the inclusion section. Laser cut the position of the target mineral recorded in advance. Use dichloromethane to dissolve the glue and other impurities.

[0034] (4) Prepare a visualization groove, fix the rock sample, and install the visualization groove in the high-pressure chamber.

[0035] The specific process includes designing the size of the visualization groove according to the rock sample and obtaining the visualization groove by laser engraving. The visualization groove is made of a transparent material, preferably transparent glass. The rock sample is placed in the visualization groove, and a visualization cover plate is arranged above the rock sample. The visualization cover plate is made of a transparent material, preferably transparent glass. Epoxy resin glue is evenly coated on the edge of the visualization cover plate or the visualization groove, and attention should be paid to controlling the dosage and strength to avoid the glue seeping into the middle groove and channel part, and then the two are bonded and fixed.

[0036] Existing technologies often use X-ray CT scanning, etc., and use visualization software for experimental observation and information extraction. In-situ synchronous monitoring cannot be achieved, and sample re-preparation is required for each measurement. It is difficult to find the accurate positioning of the original minerals. For example, traditional off-line detection methods such as X-ray fluorescence and neutron-induced prompt gamma-ray analysis technology need to destroy the sample structure, resulting in the loss of continuous data on the dynamic dissolution process and making it difficult to capture the instantaneous changes at the mineral interface reaction; although core spectral scanning has the advantage of non-destructiveness, its resolution is limited by the laser excitation depth, and it cannot achieve in-situ tracking of the micron-level dissolution interface, and complex pre-treatment is required to remove attachments, interfering with the real dissolution environment; chemical analysis methods rely on intermittent sampling, resulting in significant data lag, and oxidation / reduction interference is easily introduced during the sample preparation process, unable to reflect the real dissolution kinetics process. These defects seriously restrict the spatio-temporal resolution and data reliability of the research on the dissolution mechanism of uranium minerals.

[0037] (5) Conduct on-line monitoring and analysis of the dissolution of uranium minerals.

[0038] Example 1

[0039] The technical solution of this application can play a guiding role in the core work of in-situ on-line monitoring experiments. Taking the preparation of core samples before in-situ leaching in the Qian IV area of the Qianjiadian uranium deposit in the southern Songliao Basin as an example, the Figure 1 characterization method of the shown embodiment will be described.

[0040] An on-line monitoring experimental method for the dissolution of uranium minerals, as Figure 2 shown, includes the following steps:

[0041] S100: Sampling the core of the ore-bearing section.

[0042] For example, S110: Sampling the core of the ore-bearing section, including field core observation, collection of borehole data, field core logging, and field core sampling. The collection of borehole data includes the collection and collation of data such as well logging, logging, seismic, and paleontological data in the study area; field core logging includes the identification, logging, and sampling of typical borehole cores in the study area.

[0043] S200: Making slides of rock ores.

[0044] For example, S210: According to the well logging and logging data that have been sorted out, select ore-bearing zone samples from the core samples of the Qian IV area before in-situ leaching and make polished sections, and produce inclusion slices with a thickness of 3 - 5 mm.

[0045] S300: Selection of the target observation area.

[0046] For example, S310: Place the prepared rock and ore inclusion slices under a scanning electron microscope for observation. Select the required typical minerals according to the purpose of the in-situ monitoring experiment, perform point, line, and area scans on them, photograph the morphology of the area where the target minerals are located and the surrounding minerals, debris, etc., and record the morphological characteristics and element distributions before the reaction. Locate the target observation area under a polarized light microscope, take pictures and mark the positions of the target minerals. If the experimental purpose of the embodiment of the present application is to explore the reaction laws of different types of uranium minerals in the uranium reservoir with the CO2 + O2 leaching agent and reveal the dissolution and precipitation conditions of different types of uranium minerals under the CO2 + O2 leaching environment, the target observation points selected are uranium minerals. After the target observation area is determined, wipe the surface of the rock inclusion slice with anhydrous ethanol and polish it.

[0047] S400: Cutting of the target observation area.

[0048] For example, S410: Take the polished rock thin plate sample, use a laser to cut the position of the pre-marked target observation area, and ensure that the set cutting shape and size match the marked target observation area.

[0049] S500: Sol of the target observation area.

[0050] For example, S510: Place the target observation area cut by the laser into a petri dish, pour dichloromethane to submerge it, let it stand for 1 - 2 days, and dissolve the glue and other impurity substances.

[0051] S600: Engraving of the target observation area.

[0052] For example, S610: Design a groove in CAD software that fits the size of the cut target observation area. Then import the groove template into the laser instrument and engrave it on the transparent glass with a laser to serve as the bottom plate of the water-rock reaction visualization rock and ore thin plate. It should be noted that the closer the designed groove size matches the size of the cut rock thin plate, the better.

[0053] S700: Molding of the visualization rock and ore thin plate, as Figure 3 shown.

[0054] For example, S710: There are two methods to fuse two pieces of glass in the visualized rock and ore thin plate for water-rock reaction: the high-temperature method and the gluing method. Since high-temperature heating will cause the minerals on the thin rock slices in the middle groove of the two pieces of glass, i.e., the visualized channel, to react, the gluing method is adopted in the embodiments of the present application. Put the rock slice after sol into the groove, then take a piece of transparent glass as the cover plate and cover it, and apply epoxy resin glue around the top and bottom plates of the water-rock reaction visualized rock and ore thin plate. Pay attention to controlling the dosage and strength to avoid the glue seeping into the middle groove. After evenly applying, fix and bond the surroundings of the top and bottom plates to complete the production of the water-rock reaction visualized rock and ore thin plate.

[0055] For on-line monitoring and analysis of the dissolution of uranium minerals, place the prepared rock and ore thin plate in a sealed visible chamber and connect it to the leaching solution circulation system (equipped with CO2 / O2 injection interfaces). According to the sample analysis and monitoring cycle, collect high-definition microscopic imaging data at different time periods, and then distinguish the differences in the dissolution reaction interfaces at different time periods to support the research on the dissolution mechanism of uranium minerals. During the in-situ monitoring experiment of CO2+O2, the visualized samples under the microscope are as Figure 4 shown, and the experimental results are as Figure 5 shown, realizing the in-situ non-destructive monitoring of the uranium mineral leaching process and the real-time collection of dissolution data at the same monitoring point at different stages, providing a basis for quantitatively characterizing the uranium mineral-solution interface reaction and the evolution process of surface micropores, and revealing the solute diffusion and dissolution mechanism.

[0056] The above embodiments are only used to illustrate the present application. The structures, installation positions, and connection methods of each component can all be changed. Any equivalent transformation and improvement based on the technical solutions of the present application do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of each embodiment of the present application.

Claims

1. A method for preparing an experimental sample for on-line monitoring of uranium mineral dissolution, characterized in that, Place the rock sample through setting a visualization groove, the visualization groove is made of transparent material, and its bottom is a plane.

2. The preparation method of the online monitoring experimental sample for uranium mineral dissolution according to claim 1, characterized in that The material of the visualization groove is transparent glass.

3. The preparation method of the on-line monitoring experimental sample for uranium mineral dissolution according to claim 1, characterized in that, A visualization cover plate is arranged on the rock sample, the visualization cover plate is made of transparent material, and its edge is adhesively fixed to the edge of the visualization groove.

4. The method for preparing an online monitoring experimental sample for uranium mineral dissolution according to claim 3, wherein The material of the visualization cover plate is transparent glass.

5. The method for preparing an online monitoring experimental sample for uranium mineral dissolution according to claim 3, characterized in that, Evenly coat epoxy resin glue on the edge of the visualization cover plate or the visualization groove, and adhesively fix the two.

6. An on-line monitoring experimental method for the dissolution of uranium minerals, characterized in that, It includes the preparation method of the online monitoring experiment sample for uranium mineral dissolution according to any one of claims 1 to 5.

7. The online monitoring experimental method for uranium mineral dissolution according to claim 6, characterized in that, It includes the following steps: (1) Sample collection, sampling; (2) Rock and ore section preparation: Select the sample in the ore-bearing zone and polish it to make an inclusion section with a thickness of 3 - 5 mm; (3) Select the target observation area, cut and dissolve the glue to obtain the rock sample; (4) Prepare the visualization groove, fix the rock sample, and install the visualization groove in the high-pressure chamber; (5) Conduct online monitoring and analysis of uranium mineral dissolution.

8. The online monitoring experiment method for uranium mineral dissolution according to claim 7, characterized in that, The process of selecting the target observation area in step (3) includes: Select the target mineral through a scanning electron microscope, photograph the morphology of the area where the target mineral is located and its surrounding minerals, debris, etc., and record the morphological characteristics before the reaction; Search for the target mineral under a polarized light microscope, take a photo and mark the position of the target mineral; After determining the marked position, clean the surface and polish the inclusion section.

9. The online monitoring experimental method for uranium mineral dissolution according to claim 7, characterized in that, In the glue dissolution process of step (3), use dichloromethane to dissolve the glue and other impurities.

10. The on-line monitoring experiment method for uranium mineral dissolution according to claim 7, characterized in that, The process of preparing the visualization groove in step (4) includes: Design the size of the visualization groove according to the rock sample, and laser engrave to obtain the visualization groove.

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