The characteristics of surface uranium mineralization, ore characteristics and uranium geochemistry in the southern Weijing area, Siziwang Banner, Inner Mongolia were described, the geochemistry characteristics of constant, trace and rare earth elements in the NE-trending ore-bearing structures were studied. The results show that the uranium mineralization is closely related to the adsorption of gelatinite and ferric oxide, and the U is positively related to P₂O₅. According to the characteristics of uranium mineralization, the genesis of uranium mineralization is discussed, and it is considered that the ore-bearing hydrothermal solution rises along the structure to a special redox interface, after unloading, the uranium enters into the crystal lattice of apatite by isomorphism, and forms uranium-rich gelophosphate, at the same time, heavy rare earth and strontium are enriched and precipitated together.

At the later stage of production in the uranium mining area, the metal production usually continues to decline, and the metal concentration also changes with the influence of the intensified leaching process. At this time, the production cannot be accurately calculated by the liquid pumping volume and the concentration. Based on the induction and analysis of production parameters, a multiple linear regression model and an artificial neural network model are established for the prediction of daily metal production in a single mining area. The results show that both of them have good accuracy and generalization ability, the effect of artificial neural network model is better, the average error of metal daily production prediction is only -0.36%, the outliers are less and the error distribution is balanced. The accuracy of this method is significantly improved compared with the simple calculation to obtain the daily metal production. The use of artificial neural network model to predict the production of the mining area can provide solutions and theoretical guidance for the adjustment and change of leaching process and production system.

Filtering mechanism and effect of many kinds of filters have been systematically studied. Assuming that the particles are spheroid of equal size and arranged in an inclined cube, the initial minimum pore diameters of gravel filter and porcelain granule pre-coated filter are calculated to be 0.310 and 0.155 mm, respectively. Because of the filtration effect, the pore diameter of gravel filter and porcelain granule pre-coated filter gradually decreases with the extension of time, and the filtration effect is good. The diameter of the hole of the filter without gravel and wrapped with mesh is 0.180~0.270 mm, and the diameter is basically the same after assembly, this filter only has the effect of blocking, and the filtering effect is poor. The hole wall of the filter without gravel or with uncompacted filling may collapse or fall out of sand, and there are too many debris in the leaching solution. Mercury injection test shows the maximum pore throat diameter in sandstone uranium deposit is 0.032 mm, and all filters have no barrier effect on unstable silty clay debris and chemical precipitation.

A molybdenum ore has the characteristics of low grade, difficult separation, various molybdenum minerals and some of them are located in inclusions. In view of the refractory characteristics of the molybdenum ore, the leaching mechanism was analyzed. At high temperature, the leaching test was carried out with high concentration sulfuric acid. The results show that high concentration sulfuric acid crash pyrite inclusions; increasing the amount of sulfuric acid, increasing the temperature, increasing oxidant dosage and reducing the ore size are beneficial to the Mo leaching rate. Under the conditions of particle size -0.15 mm (accounting for 75%), sulfuric acid dosage 20%, MnO₂ dosage 2%, leaching temperature 90 ℃, leaching time 3 h, the leaching rate of molybdenum increases from 30%~40% of conventional stirring leaching to 72%. The research results put forward some countermeasures for the exploitation and utilization of molybdenum ore resources, and made a breakthrough in molybdenum leaching effect.

The "CO₂+O₂" neutral leaching uranium process is adopted for a sandstone uranium deposit in Xinjiang, there are mining areas with poor permeability and low water content of ore-bearing aquifers. In this kind of mining area, there are some problems in the single-hole oxygen adding mode, such as gas blocking, water returning from oxygen flowmeter, large maintenance workload and low oxygen solubility. Taking 5^# mining area as an example, the study using micropore aeration oxygenation technology shows that the residual oxygen of single hole leachate increases by 226.85% on average, and the uranium concentration of leachate increases by 43.29% on average, the unit oxygen consumption per ton metal decreased by 30.77%, and the cost of developing oxygen facilities in mining area decreased by 96.09%. The technology of micropore aeration oxygenation technology solves the difficulty of oxygen addition in the process of "CO₂+O₂" neutral leaching, and provides a reference for oxygen addition in in-situ leaching of sandstone uranium ore.

Generally, the wire-wrapped filter in dense fixed-bed adsorption tower is designed based on experience, the design process lacks theoretical analysis and experimental data. The liquid outflow capacity, filtering effects, pressure drop and cleaning methods of wire-wrapped filter were researched by adsorption test using dense fixed-bed adsorption tower. The results show that the liquid outflow capacity and filtering effects could be satisfied when the superficial linear velocity was 65 m/h, since the slot area of wire-wrapped filter was 4 times the area of the liquid inlet. The change rule of pressure drop, cleaning methods and its effects of wire-wrapped filter were summarized. The design and selection of wire-wrapped filter were provided by the test. Also, the correct use of wire-wrapped filter in actual production was clarified. The test results could provide reference for the subsequent development of high flux ion exchange equipment.

In response to the phenomenon of a decrease in uranium concentration in the qualified leaching solution of a uranium mine in Inner Mongolia during the in-situ leaching process, the production and operation data were analyzed based on the adsorption—leaching theory, and the reasons for the decrease in uranium concentration were identified, and through static leaching experiments, the leaching agent formula was optimized. The best leaching effect was achieved by leaching with a solution of 80 g/L NaCl+18 g/L NaHCO₃+18 g/L Na₂CO₃. Based on the results of the leaching agent test, the optimization and validation of the leaching agent preparation process in the mining hydrometallurgy process show that the optimized leaching agent preparation method is more suitable for CO₂+O₂ in-situ leaching uranium mines. The research results can provide technical support for optimizing the hydrometallurgical process of other neutral in-situ leaching uranium mines.

There are some problems such as unsatisfactory well washing effect and high cost of well washing in the common washing methods of in-situ leaching uranium mines. The negative pressure well washing technology is used to carry out an experimental study in a leaching uranium mine in Inner Mongolia. The results show that the deeper the packer is, the more obvious the washing effect is. Compared with the compressed air washing process, the negative pressure washing process can improve the instantaneous flow rate of the borehole more, and the instantaneous flow retention time is longer.

The automatic industrial control system is often used in the in-situ leaching and mining industry. With the increase of the monitoring and control equipment in the in-situ leaching mine, the traditional analog communication has the disadvantages of high cost of line laying and large number of I/O modules. Modbus communication mode is used for the frequency converter in the well pad control system of an in-situ leaching mine in Inner Mongolia to complete the remote acquisition and control of its parameters and reduce the project construction cost. The remote one-button start and stop of the frequency converter and frequency regulation at the uranium leaching monitoring center in a certain place are realized, which further improves the work efficiency.

The problems of low production efficiency and poor safety exist in Mianhuakeng mine due to the imbalance of mining equipment allocation. According to the characteristics of mining equipment allocation and the production status of Mianhuakeng mine, an optimization model of mining equipment allocation based on linear theory is constructed, and the main mining equipment under two mining technologies are calculated and analyzed by using the model. The overall plan of intelligent construction of mining equipment in Mianhuakeng mine is proposed, which includes wireless remote control of shoveling equipment, precise guidance control of driving equipment and intelligent unmanned transportation of underground electric locomotive and rail. Meanwhile, the optimization plan of main mining equipment configuration under different mining technology is given.

Polymyxin E is produced by fermentation of Bacillus polymyxa. It was usually purified by ion exchange. The extraction indexes of polymyxin E by D152 (weak acid cation resin) was studied, and the adsorption capacity, elution rate and yield of polymyxin E were obtained by matching D152 resin with the existing process equipment. The adsorption capacity of D152 resin can reach 6.8×10⁶ U/mL (wet resin), and the total yield is ≥98.0% under the pH of polymyxin E filtrate in 6.0~7.0, the chromatotiter in 3.0×10⁵ U/mL, the adsorption velocity of 1.0 BV/h and sulfuric acid elution velocity of 1.0~1.5 BV/h under the chromatotiter was adsorbed by three columns in series. After 6 months of continuous operation, D152 resin has stable performance.

The continuously discriminative monitoring of radon and thoron is a significant project in the realm of radiation protection, which can provide statistical supports for the accurate estimation of internal exposure dose in radon-thoron hybrid environment. Using the improved ZnS scintillation cells and based on the delay count method (DCM), an experimental device for radon-thoron continuous monitoring has been devised. This device has been tested under both laboratorial and on-site conditions, the measurement results from this device were compared with that from Alpha Guard DF2000. As a result, the deviations of the measurement values of this device and Alpha Guard DF2000 are less than 10% for both radon and thoron even when the radioactive concentrations of radon and thoron differ drastically (the ratio is over 1∶30), besides, the disturbance from the previous sampling durations upon the long-term monitoring values has been eliminated. To conclusion, this device is capable to discriminate radon and thoron accurately under distinctively different concentrations of radon and thoron.

Phased construction is one of the characteristics of tailings pond spillway, and the hydraulic characteristics of the spillway vary greatly at different stages of operation. Based on the VOF method and RNG k-ε turbulence model, the flow pattern, velocity and energy dissipation rate of the initial design scheme and optimization design scheme of the spillway were simulated by Flow-3D. The results show that the flow pattern during the infrastructure period is relatively smooth, the shape of the spillway is reasonable, while the spillway in the built-up stage has problems such as steep slope in the stepped section and the water surface line extends beyond the side walls. The flow pattern of the optimized spillway is good, the maximum flow velocity in the spillway is about 17.31 m/s and the energy dissipation rate is about 78.53%, the shape of the optimized spillway is reasonable. The research results can be used to guide the design of spillway under phased construction.

In the stage of in-situ leaching uranium test, production and groundwater remediation, due to the selected indicators are not appropriate, the wrong judgments on the original state of groundwater, metal leaching conditions, redox environment, solution leakage, leaching range control etc. are often caused, which lead to ineffective control measures or worsening of existing problems. Based on the environmental characteristics of acid leaching, CO₂+O₂ leaching and groundwater remediation, the indicators such as U, electrical conductivity, TDS, pH, Eh, , in the leaching solution are analyzed, and the indicators that should be selected in different leaching environments, or in the groundwater remediation and stabilization periods of decommissioned mines are proposed in combination with examples. The practice has proved that the recommended indicators can truly reflect the leaching environment and groundwater remediation effect, and can provide a strong evidence for the government to formulate groundwater remediation indicators.

The high-level underground research laboratory (URL) is not only a test facility used to understand the deep geological environment and crustal stress, obtain deep rock and water samples, and verify the long-term performance of engineering barriers in the real deep geological environment, but also an important means to develop and verify the construction, backfilling and sealing technologies of the repository. It is an essential platform for the research and development of high-level radioactive waste disposal technology. In order to reduce safety risks in the operation of URL, by analyzing factors such as the engineering characteristics, spatial structure, and personnel distribution of URL, and in response to potential safety risks in URL, a study was conducted on the design of emergency evacuation facilities for URL. Through research, rescue chambers were identified the location of the mobile rescue capsule and the disaster avoidance route of the URL have been developed, and emergency plans have been developed for the safe operation of the URL under disaster conditions.

According to the water quality characteristics of fluorine-containing mine water in a uranium mine, the size of structures and key equipment, hydraulic conditions and other parameters were designed and calculated to achieve the purpose of strictly controlling the dosing amount, the flow rate of mixing facilities and the total head loss, the velocity gradient of flocculation tank, the Reynolds Number of sedimentation tank and other process parameters, so as to maximize the flocculation and sedimentation effect. Based on the operation cost and water quality monitoring data of the project in the first year, the existing problems and presented improvement measures were summarized.

Regular scientific testing and evaluation of the quality and safety of uranium decommissioning and treatment engineering facilities is an important activity to make up for engineering defects and continuously improve treatment measures, which will ensure the long-term effective isolation of uranium mine radioactive waste residue from the ecological environment. The study used on-site observation, in-situ strength detection, concealed engineering detection and other methods to complete the inspection of the structure of the decommissioning and treatment engineering facilities of some uranium mines in China that had been completed for 20~30 years, and established the quality assessment method of decommissioning treatment facilities through the investigation and analysis of the causes of damage. The results of structural inspection and evaluation show that the quality of decommissioning treatment facilities is good, the resistance to the influence of natural stress is guaranteed, and it is necessary to carry out continuous and active monitoring work. It also puts forward suggestions for future decommissioning design, construction and management.