Latest ArticlesThe accuracy of hydraulic conductivity holds great significance for the subsequnce research and exploitation of the in-situ leaching sandstone-type uranium deposit. Taking the in-situ leaching technology of sandstone-type uranium deposit as the research object, based on the current research status of hydrogeological well completion technology and hydraulic conductivity calculation methods at home and abroad, this paper analyzes the influencing factors of hydrogeological well completion quality on hydraulic conductivity calculation. Through VB visual programming software, the loopholes of human error in calculation and curve drawing are made up, and the calculation of hydrogeological parameters of deposit is more concise, efficient and accurate.
As the mining depth of a uranium mine continues to increase, the ore body shows a trend of decreasing thickness and increasing inclination angle. This paper focuses on the steeply inclined thin ore veins of the uranium mine, utilizing the AHP-TOPSIS method for comparative analysis of different mining methods, and proposes a high-segment continuous efficient collaborative mining method suitable for the thin ore veins in this mine. Based on this, the numerical analysis is conducted using FLAC3D to examine different structural parameter schemes of the stope, analyzing the stress field, displacement field, and distribution characteristics of the plastic zone during the mining process, ultimately acquiring the optimal stope structural parameters. The results indicate that: no tensile stress was observed in the top and intermediary pillars in scheme 1 to 4, while a small amount of tensile stress occurred in schemes 5 and 6; the proportion of the plastic zone varies from 22.52% to 27.98% across scheme 1 to 6, with scheme 3 demonstrating better stability. Considering both safety and economic factors, the optimal stope structural parameters are determined to be a top pillar height of 5 m and an intermediary pillar width of 8 m (scheme 3).
In order to clarify the leaching effect of horizontal well technology on in-situ leaching of uranium, a numerical simulation method was used to study the influence of different parameters on "Horizontal Well Injection-Vertical Well Pumping" and conventional "Vertical Well Injection and Pumping". The results show that compared with "Vertical Well Injection and Pumping", the length of horizontal wells is proportional to the leaching range, the vertical leaching range of "Horizontal Well Injection-Vertical Well Pumping" is small, the plane sweep efficiency is high, the dead corner of leaching is small, and the effective utilization rate of leaching solution is high; it has a wide coverage in the horizontal direction and have significant advantages in the treatment of thin uranium ore deposits. The ratio of horizontal permeability to vertical permeability has a greater impact on the leaching of "Vertical Well Injection and Pumping". When the vertical permeability is low, the leaching effect of horizontal well sections is better than that of vertical well sections; the amount of pumping and injection fluid is positively correlated with the leaching range. As the amount of pumping and injection fluid increases, the dead corners of leaching of both "Horizontal Well Injection-Vertical Well Pumping" and "Vertical Well Injection and Pumping" decrease. The increase in the amount of pumping and injection fluid has a greater impact on the leaching effect of "Horizontal Well Injection-Vertical Well Pumping". When the flow rate reaches 210 m3/d, the leaching range of the ore layer of "Horizontal Well Injection-Vertical Well Pumping" is higher than that of generalized "Vertical Well Injection and Pumping".
The electric control valve in the 76Ge isotope production process is controlled by the PID module of the DCS (Distributed Control System) to regulate the internal pressure of the cascade pipeline. However, when the pressure of the process system fluctuates greatly, the existing control method of electric valve can not achieve the optimal control effect, which leads to the controlled process pressure exceeding the operating safety limit and has a serious adverse impact on the safe and stable operation of the process system. Aiming at the problem of weak control performance of electric valve under abnormal pressure, this paper put forward a control scheme to optimize DCS control configuration program of electric valve. Actual operation shows that the optimized control program avoids significant fluctuations in process pressure under abnormal conditions, effectively ensuring the safe and stable operation of the 76Ge isotope production line.
To investigate the adsorption characteristics of sodium dodecylbenzene sulfonate on scheelite surface, the water bath shaking method was used to study the adsorption capacity, kinetics, and thermodynamics. The effects of pH, reagent concentration, temperature on the adsorption characteristics were explored using kinetic and thermodynamic equation models. The results show that under pH=10, the adsorption capacity of sodium dodecylbenzene sulfonate on scheelite surface is the largest, while under pH=7, the adsorption rate is the fastest, which conforms to the pseudo-second-order kinetic equation. Within a certain range, the adsorption capacity of dodecyl benzene sulfonate on scheelite surface is positively correlated with the reagent concentration and temperature. The adsorption process conforms to the Freundlich equation, which is an endothermic reaction of heterogeneous multilayer adsorption.
The "CO2+O2" leaching process is an artificially intensified water-rock interaction process that leads to the dissolution of non-uranium minerals, which enter the leaching solution system and cause changes in the dissolution and precipitation state of the minerals in the leachate. Geochemical simulation methods were used to simulate ion species in the leachate and the mineral leaching equilibrium studying the dissolution, migration, and precipitation of minerals during the in-situ leaching mining process. For the first time, the conditions and influencing factors for the precipitation of manganese minerals were studied, targeting the characteristics of strong groundwater reducibility and high carbonate content in the target deposit.The results show that under neutral leaching conditions, uranium in the leachate mainly exists in the form of UO2(CO3
In the process of uranium dioxide hydrofluorination in the uranium conversion workshop, the opening and feeding of uranium dioxide raw material drums need to be operated manually, in order to reduce the risk of radiation exposure of the operators, the design of the handwheel lid opening robot control system for uranium dioxide raw material drums. The system adopts STM32F407IG series as the main control chip, and uses USB communication module to communicate with the servo motor of the robot arm for the motion control of the robot arm; proposes and adopts the robot arm positioning method based on the combination of key point detection and robot inverse kinematics to realize the accurate positioning and smooth switching of the robot on the handwheel lid of the uranium dioxide raw material drum; at the same time, designs the monitoring and control interface of the upper computer. Experiments show that the robot can complete the identification and localization of the handwheel well, and the mechanical gripper can smoothly insert into the spokes of the handwheel and rotate as required.
This paper focuses on the abnormal fluctuation of yield during the electron beam welding process of fuel rods. Considering that the main defects leading to the rejection of fuel rods are surface scratches and out-of-tolerance straightness, through analysis and research, it is clarified that the direct causes of the abnormal yield of fuel rods are the excessively large aperture of the welding tooling baffle, the excessive use of the welding top, and the design of the top bearing. By taking measures such as reducing the aperture of the baffle, determining the reasonable number of uses for the welding top, and designing the top bearing, defects can be controlled in a timely manner, the yield can be improved, the manufacturing cost can be further reduced, and a foundation can be laid for the subsequent exploration of fuel rod manufacturing processes.
In order to solve the problems of microwave plasma decomposition of 13CF4, such as complex operation process, harsh decomposition conditions and easy corrosion of reaction tubes,the thermal catalytic decomposition of 13CF4 to produce 13CO2 was studied. Under the condition of anhydrous and high temperature, 13CF4 was decomposed into 13CO2 by gas-solid reaction between 13CF4 and solid defluorination agent, using γ-Al2O3 as solid defluorination agent, meanwhile, the metal oxide in the defluorination agent is converted into metal fluoride. The results show that when the flow rate of reaction gas is 120 mL/min, the loading amount of catalyst is more than 60 g, the content of O2 in feed gas mixture is more than 50%, and the temperature of high temperature tubular furnace is 900℃, the conversion of γ-Al2
Guyuan 460 associated uranium molybdenum resources belong to amorphous colloidal sulfur molybdenum ore, which has the characteristics of complex mineral properties, difficult beneficiation and metallurgy, and long process flow. After more than 20 years of experimental research and production practice, a process development technology system of "oxygen pressure acid leaching modified filtration extraction separation process water cycle" has been formed. This article summarizes the technological innovation process of Guyuan 460 uranium molybdenum mine, which comprehensively innovates and practices from multiple aspects such as efficient leaching of uranium molybdenum ore, solid-liquid separation of slurry, separation and purification of uranium molybdenum, product preparation, process water recycling, key equipment and material engineering applications. Finally, an oxygen pressure leaching demonstration mine with an annual processing capacity of 200 000 tons of uranium molybdenum ore was built, greatly improving the scientific and technological level of complex associated uranium molybdenum resource development in China. It is a typical embodiment of new quality productivity in the mineral field.