The removal method of superstandard components of uranium acid seepage water from sulphur-containing uranium waste rock in a mining area was studied. Firstly, 1 g/L mineral powder was added to the wastewater exceeding the standard to remove Cd, Cu and part U, and then the pH of seepage water from the waste rock landfill on the south and north sides was adjusted from 2.78 and 2.66 to 4.70 and 4.30, respectively, and the optimal contact reaction time was 30 min. The effects of Mg(OH)₂, Ca(OH)₂, Na₂CO₃ and NaOH on the further treatment of U, Mn and Zn in the effluent treated by ore powder were compared. The results show that Ca(OH)₂ has the best removal effects on U, Mn and Zn.Under the conditions of 0.32 and 0.96 g/L of Ca(OH)₂ and pH of 7 ~ 8, the removal rate of U, Cu, Cd, Zn and Mn can reach over 99.8%, over 90%, over 90%, over 95% and over 75.5%, respectively. And the settling speed is fast, and the suspended liquid volume can be reduced by about 70% after standing for 60 min. The precise calculation of the change of ion concentration during the addition of Ca(OH)₂. The results of sediment characterization show that hydrotaltale-like substances are formed during the purification process,Mn²⁺ and Zn²⁺ ions entered the hydrotalc structure and are removed,and uranyl ions may be removed by electrostatic adsorption with hydrotalc, surface complexation or interlayer anion exchange.

The effects of the changes of speed (N), distance (C₁) from the bottom and pitch (C₂) of the double-layer baffle three-arc blade composite paddle on the flow field in the stirring tank using particle image velocimetry (PIV) were studied. The flow field characteristics of the double-layer baffle three-arc blade propeller and the double-layer baffle-free three-arc blade propeller were simulated and compared. The results show that when the rotation speed N=110 r/min, the velocity distribution of the flow field in the kettle is relatively uniform, and the high-speed zone in the kettle is concentrated near the propellers. When C₂=0.27h(h is the liquid level height of the stirred tank), the connection flow between the propellers is stable, and the overall mixing capacity in the kettle is significantly enhanced. When C₁=0.29h, the area of the low-velocity zone in the kettle is greatly reduced. The baffle of the double-layer baffle three-arc blade propeller limits its radial pushing capacity, but the axial pushing capacity is significantly enhanced. The research results can provide a reference for the application of double-layer baffle three-arc blade propeller in practical industry.

Aiming at the issues of low computational efficiency and insufficient intelligence in predicting hydrometallurgical process parameters, a process optimization control model that utilizes 1D-CNN for predicting copper ion concentration and Seq2Seq for predicting mass transfer rate, with the objective of maximizing economic benefits was proposed. The optimization problem is solved using the DDPG algorithm. The results of numerical simulation and empirical study show that the model can predict the parameters of copper extraction process with high accuracy, realize the effective optimization and adjustment of parameters, and promote the improvement of economic benefits.

Aiming at the problems of low pre-treatment efficiency and significant mass spectrometry interference in the determination of rare earth elements in coal-related samples, a method for the determination of rare earth elements in coal and fly ash samples by high-temperature and high-pressure microwave digestion-ICP-MS in a mixed acid system of HNO₃-HF-HClO₄-H₂SO₄ was established. The effects of pre-treatment methods, sample weight, digestion system and mass spectrometry interference on the determination results were investigated. The results show that the linear correlation coefficients of the calibration curves are all greater than 0.999 6, the detection limits are 0.003 7~0.042 μg/g, the relative standard deviations (RSD, n=11) of the determination results of each element are all within 5.85%, the recoveries of standard addition are 95.0%~107.2%, and the relative errors are all less than 6.95%. The method has high accuracy and good stability, which greatly improves the determination efficiency.

To address the problems such as insufficient real-time data analysis, lack of intelligent decision-making support, and limited dynamic optimization capabilities of in-situ leaching dynamic mining system in practical application, the advantages of integrating Digital Twin technology with the in-situ leaching process for uranium extraction were analyzed. By incorporating advanced technologies such as muon imaging, fiber-optic water level monitoring, advanced sensing technologies, artificial intelligence, and big data analysis, an efficient digital-intelligent uranium mining platform was constructed. The platform includes geological structure model, groundwater seepage model, reactive transport model, and intelligent agent model. The core algorithms cover deep learning, data assimilation, multi-objective optimization, and uncertainty analysis. The establishment of the dynamic in-situ leaching mining system can improve the efficiency of uranium resource development and can provide valuable reference for the extraction of other mineral resources, thus having certain theoretical significance and practical value.

In order to solve the issue of low automation in the hydrometallurgical process in in-situ leaching of uranium, especially in the preparation of yellowcake from precipitation slurry using plate and frame filter presses, a horizontal belt vacuum filter was selected for the first time in an in-situ leaching of uranium mine to conduct a filtration dewatering experiment on sodium diuranate precipitation slurry. The influence of different operating conditions on moisture content of yellow cake products was investigated. The results show that under the conditions of a filtration vacuum of -0.06~-0.08 MPa, a filter cloth precision of 38 μm, a slurry residence time of 640 s, a feed flow rate of 353~589 kg/h, and a backwash and sealing circulation water flowrate of 10 m³/h, the entire process from cloth feeding to filtration, dewatering, cake discharge, and cloth backwashing can be automatically cycled and run continuously and stably. The product moisture content meets the first-grade standard, satisfying the dewatering capacity requirements for a mine producing about 500 t of metallic uranium per year. The technical feasibility of using belt vacuum filter to dehydrate the precipitated slurry has been preliminatively confirmed. The technical feasibility of using belt vacuum filter for dewatering the precipitation slurry has been preliminatively confirmed. The filtration dewatering process can reduce the labor intensity of operators, reduce the radiation hazard, and improve the automation of the entire hydrometallurgy process, it has value for promotion and application.

Extracting vanadium from stone coal vanadium ore with sericite as the main material and vanadium in the form of isomorphic vanadium by barium salt roasting—acid leaching was studied. The effects of grinding fineness, dosage of barite, roasting temperature, roasting time, liquid volume to solid mass ratio, sulfuric acid dosage, leaching temperature and leaching time on vanadium leaching rate were investigated. The results show that the vanadium leaching rate can reach 89% under the conditions of grinding fineness of -200 meshes of 70%, barite content of 5%, roasting temperature of 850 ℃, roasting time of 16 h, liquid volume to solid mass ratio of 2.0, sulfuric acid dosage of 8%, leaching temperature of 25 ℃ and leaching time of 2 h. The leaching effect is good.

The direct leaching of Cu and Co from a copper-cobalt mixed ore in Congo(Kinshasa) by oxidation leaching method and reduction leaching method was studied. The leaching behavior of Cu and Co by the two methods was compared and analyzed. The effect of flotation—oxidation leaching on the leaching rate of copper and cobalt was further discussed. The results show that the leaching rates of Cu for oxidation and reduction leaching are about 80% and 70% respectively, and the leaching rates of Co are about 63% and 57% respectively, and the oxidation leaching effect is better than that of reduction leaching. By using the combined flotation—oxidation leaching process, the Cu and Co grades in closed-circuit flotation concentrates are 16.84% and 6.53%, respectively and the combined recovery rates of Cu and Co are 91.71% and 61.87%, respectively. The recovery effect of Cu and Co can be significantly improved.

The efficient utilization of secondary silver-containing resources is of great significance for making up for the shortage of silver ore resources in China, alleviating the contradiction between supply and demand, and ensuring the supply security of national strategic metals. For waste Ag-Cu filler metal, the leaching and separation of copper and silver in the HCl-H₂O₂ system was studied, and high-purity AgCl was prepared. The influence of various factors on the separation effect of copper and silver was investigated. The results show that under the optimized conditions of H₂O₂ excessive coefficient of 1.3, HCl excessive coefficient of 1.4, liquid-solid mass ratio of 11∶1, leaching temperature of 40 ℃, and leaching time of 3 h, the leaching rate of copper can reach 99.38%. The leaching residue is irregular spherical particle with particle size of 2~4 μm. The main phase is AgCl, and the main components are Ag and Cl, with total mass fraction of more than 99%.

Aiming at the dilute acid of copper smelting as raw material, the selective precipitation of copper and removal of arsenic with oxalic acid was studied. The effects of oxalic acid addition dosage, solution pH, stirring speed, reaction temperature and time on the separation of copper and arsenic were investigated. The results show that under the conditions of H₂C₂O₄/Cu molar ratio of 1.1, solution pH=0.4, stirring speed of 500 r/min, reaction temperature of 25 ℃ and reaction time of 30 min, the precipitation rate of copper is more than 98.5%, and the precipitation rate of arsenic is less than 0.20%, copper and arsenic can be separated efficiently.