The ore subjected to radioactive sorting treatment is crushed ore, with random shapes, which directly affects the accuracy of ore grade detection. To enhance the accuracy of radioactive separation detection, standard samples of uranium ore were prepared to conduct an influence test on how the shape of uranium ore affects detection efficiency. The relationship between the ore shape factor and the variation coefficient of detection efficiency was examined, leading to the establishment of a detection efficiency correction algorithm based on ore shape. Additionally, a quantification method for ore shape suitable for uranium ore radioactivity detection was proposed. The validity of the proposed detection efficiency correction algorithm has been verified through practical ore sorting tests. After implementing this algorithm, the error in uranium ore grade detection was reduced to less than 5% in over 70% of the test groups. This significantly mitigates the impact of ore shape on detection efficiency and enhances the accuracy of uranium ore grade detection.
During the production of nuclear fuel elements, hydrofluoric acid solutions with high concentration of uranium are generated. According to the requirements of the National Nuclear Safety Administration (Guoheanfa 〔2023〕 No. 158), hydrofluoric acid solutions with uranium concentrations below 0.2 mg/L can be released from regulatory control. To meet national regulatory requirements, this study utilized a hydrofluoric acid-resistant resin functionalized with specific groups to investigate its uranium adsorption performance in uranium-containing hydrofluoric acid under static and dynamic conditions. The resin’s resistance to hydrofluoric acid corrosion, saturated adsorption capacity, desorption efficiency, and reusability were systematically evaluated. The results show that the uranium concentration in hydrofluoric acid treated with this resin is reduced to below 0.2 mg/L, meeting the regulatory release criteria. Furthermore, the resin exhibits no significant decline in uranium adsorption capacity after 10 adsorption-desorption cycles. These findings provide a foundation for subsequent large-scale engineering applications.
A regional mining transportation system optimization model based on complex network planning was constructed to address the characteristics of dispersed mining of uranium deposits, diverse development methods, and complex transportation system networks in the region. Under the conditions of regional mining, a comprehensive planning and development transportation system was developed to enhance the efficiency, economy, and scientific effectiveness of the regional mining transportation system. By analyzing the spatial and geographical relationships of regional mines and the concept of intensive development, a system network diagram was established. Using network flow theory and Grey Wolf Algorithm, the global optimal solution for the regional mining transportation system was obtained. The effectiveness of the model was validated in the Xiangshan uranium mining area, and the optimal regional transportation route and lowest cost plan for the mine were calculated. The results indicate that the model meets the requirements of large-scale and intensive regional mining transportation systems, and has effective planning effects on transportation systems. It provides technical support for the economic and efficient operation of the transportation system in the Xiangshan uranium mining field, and can also provide reference for the intelligent transportation system planning of other uranium mining bases.
The well washing process is an important way to increase the well water volume and increase the production capacity in the in-situ leaching uranium mine, but with the continuous improvement of safety and environmental protection requirements, the traditional well washing method alone can no longer meet the needs in recent years. A local leaching uranium mine has further improved the safety and environmental protection of the well washing process and the efficiency of the well washing process by carrying out the optimization and improvement of the safety and environmental protection of the well washing process such as the parallel well washing technology of the air compressor, the improvement of the acid adding method, and the recycling technology of the well washing wastewater, so as to maximize the effect of well washing, and ensure that the safety and environmental protection risks of the well washing process of the in-situ leaching uranium mine are controlled.
The data of mineral resources reserves is the focus of the management of mineral resources reserves, and the national survey of mineral resources is a national and basic survey of mineral resources. Based on the national survey database of mineral resources in Henan Province, it is necessary to study and put forward a method to quickly update the resource reserve data in the mineral resources reserve database to facilitate the efficient use of the mineral resources management department, which is necessary to solve many problems such as data missing, error, redundancy and low timeliness in the reserve database and to better manage the mineral resources. By designing a computer program algorithm, the resource reserve data records in the national survey database of mineral resources and the mineral resource reserve database were automatically compared according to the relevant fields, and the differences were found. According to the differences, different program codes were adopted to update the resource reserve data in the reserve database. Compared with the method of manually updating data in daily reserves management, this method can update the resources and reserves data in the mineral resources and reserves database more comprehensively, quickly, efficiently and accurately.
Due to the change in ore properties of a certain hard rock uranium mine with the increase of mining depth, the heap leaching process of the ore encountered the problem of heap scaling. In order to solve the problem, the effects of leaching agent acidity, spray intensity, column height and particle size on heap scaling were studied. The results show that when the acidity of the leaching agent is 50.0 g/L, the spray intensity is 40.0 L/(m2·h), and the leaching period is 30 days, there is no scaling in the column leaching test, and the uranium leaching rate of -10 mm ore reaches 83.40%. The results of the 800 t ore pilot test confirms that there is no scaling in the heap with high acidity and large spray intensity, and the uranium leaching rate reaches 86.57%.
Alkaline materials were used to neutralize acidic waste residue. Open and closed experimental environments were set up with different dosing ratios and pH conditions.By monitoring the changes in pH, U, and $\mathrm{HCO}_{3}^{-}$ in the supernatant of the neutralization residue, and analyzing the mineral composition of the neutralization residue using XRD, the effect of CO2 on U stability during the neutralization process of acidic waste residue was studied. The results show that CO2 in the surrounding air during neutralization treatment affects the stability of pH and U in the neutralization residue. The fixation of CO2 by the neutralization residue under alkaline conditions is an acidification process. As the pH of the neutralization residue decreases, the CO2 fixed in the air transforms into $\mathrm{HCO}_{3}^{-}$, which gradually accumulates and causes the already stabilized U in the neutralization residue is leached out again. The pH adjustment experiment shows that there is no significant correlation between U and pH. The pH range for U leaching is 7.68~8.41, and $\mathrm{HCO}_{3}^{-}$ accumulates significantly in this range. There is a positive correlation between U and $\mathrm{HCO}_{3}^{-}$, with a correlation coefficient of 0.95. The production of $\mathrm{HCO}_{3}^{-}$ is a key factor affecting the stability of U in neutralization residue. When Ca(OH)2 is added excessively, secondary mineral CaCO3 will be generated in the neutralization residue. As CO2 is fixed, the pH of the neutralization residue decreases, and CaCO3 will partially dissolve and transform into $\mathrm{HCO}_{3}^{-}$. In the open experimental environment, only the 2.5% Ca(OH)2 experimental group and the 2.5% Mg(OH)2 experimental group maintain extremely low U leaching levels. After neutralization treatment, the pH of the neutralization residue is low, and very little CO2 is fixed in the air. $\mathrm{HCO}_{3}^{-}$ which affects U stabilityis hardly produced.
The casing for in-situ leaching uranium needs to take into account the anti-corrosion performance and pressure resistance. In view of the complex geological conditions of dense sandstone uranium deposits, the performance of casing made of three materials, namely unplasticized polyvinyl chloride(UPVC), carbon steel and glass fiber reinforced plastic(GFRP), had been comparatively investigated. The results show that UPVC casing has good corrosion resistance but poor pressure resistance; carbon steel casing has good pressure resistance but is easy to corrode and has high cost; GFRP casing is excellent in corrosion resistance, pressure resistance and tensile strength. In terms of cementing quality, the cementing strength of GFRP casing, carbon steel casing and UPVC casing with cement is 1.80, 2.91 and 0.32 MPa respectively, and the cementing strength of GFRP casing with cement shows obvious advantages. GFRP casing is the best choice for in-situ leaching uranium in dense sandstone uranium deposits, which can meet the requirements of anti-corrosion performance and pressure resistance, and can guarantee the quality and service life of the drilling.
With the development of uranium mining, uranium mining technology has rapidly advanced, but various challenges have emerged. In the process of in-situ leaching of uranium, there is often a phenomenon of decreased pumping and injection volume, which seriously affects the efficiency of uranium leaching. In response to the problem of decreased pumping and injection volume, physical, chemical, and combined well cleaning techniques have been carried out. The washing technology can solve the blockage around the wells, but its washing effect lasts for a short time and has a small impact radius, which cannot fundamentally solve the problem of decreased flow rate. The liquid flow cavitation technology is widely used in petroleum extraction, which can effectively increase the production of pumping wells and reduce the pressure of injection wells. However, it has not been involved in the in-situ of uranium process. In this paper, by comparing the difference between uranium leaching technology and petroleum technology, the cavitation device is optimized, and the drilling wellhead device is improved in the ground test, and then the liquid flow cavitation test is carried out. During the test, the operation displacement reached 2 m3/min and the pressure was about 21 MPa, which verified the feasibility of liquid flow cavitation technology in in-situ of uranium, and provided a new idea for improving the permeability of uranium mine.
With the global growth in demand for clean energy, the development of uranium ore resources and its environmental impact increasingly have raised concerns. Uranium tailings (slag), as the main by-product of uranium mining and processing, are an urgent environmental concern requiring safe disposal. This study systematically summarized the research progress of uranium tailings backfilling and safe disposal technology, and focuses on the paste filling process optimization and nano material solidification mechanism, in order to provide theoretical support for the green development of uranium resources and the safe disposal of radioactive waste.