In order to better apply the electrokinetic in-situ leaching (EK-ISL) technology to the mining of low permeability uranium ore and improve the leaching efficiency of low permeability uranium ore, it is necessary to study it with numerical simulation technology. Starting from the physical and chemical behaviors in the process of in-situ leaching of uranium, the promotion of numerical simulation technology to in-situ leaching uranium were reviewed, the basic equations and solving methods of the model of in-situ leaching uranium were summarized, the key processes that need to be described by EK-ISL model were analyzed based on this, a preliminary numerical simulation model of electrokinetic in-situ leaching uranium was proposed.

The pumping and injection units in the well site of in-situ leaching production may have the situation that the injection volume is greater than the pumping volume, resulting in the diffusion of part of the leachate pollution beyond the leaching range. Through the target optimization method of the mining area, the single hole pumping and injection volume of the well site is optimized, and the pumping and injection volume of each pumping and injection unit in the mining area is effectively controlled to keep the total pumping volume greater than the total injection volume by 0.5%, so that the leaching solution is controlled within the well site as far as possible. According to the optimization results, the pumping and injection volume of each unit can be changed to realize the production and decommissioning of the mining area at the same time.

On the basis of meshing recovery area, design recovery stripes and recovery routes, forming the recovery strategy of starting from the cross section of flood shaft, advancing respectively upward and downward in wedge and wave shape, and at the same time put forward calculation formula of recovery capability of each route, and slope steady and draining measures during recovery process. The method is then verified by a specific engineering case, the results show that this method can eliminate interference of recovery machines, prominently boost recovery efficiency, and calculate precisely of recovery capability, which is good for recovery management.

In view of the shortage of important structural components, such as the liquid discharge device, upper head, resin buffer device, leachate inlet structure, liquid distribution device and resin buffer tank of the packed moving bed adsorption tower, the improved design of the structure was carried out by using the finite element method and the structural local adjustment method. The improved packed moving bed adsorption tower has been optimized in terms of functionality, use failure rate, replacement and maintenance frequency, simple and convenient operation and economy, the component structure is simple, the replacement of parts is convenient, reaching the expected goal.

The existing ore treating and leaching technology for low grade uranium-bearing molybdenum ore has the problems of low molybdenum leaching efficiency, high consumption of leaching reagents and high cost of industrial production. By the means of curing the ore with acid, the effects of particle size, acid content, acid curing ways, temperature and time on the curing effect and molybdenum leaching rate were studied mainly. The experimental results show that the molybdenum leaching rate of low grade uranium-bearing molybdenum ore can reach 72% after column leaching under the conditions of -3.2 mm size, 13% mass fraction of mixed acid, 4∶1 mL/g liquid-solid ratio, 85 ℃ curing temperature and 15 h curing time. The process has the advantages of short leaching cycle and low liquid-solid ratio, which is conducive to industrialization.

The relationship between the production cost and the lean uranium abundance of uranium enrichment plant was studied. By analyzing the influencing factors of uranium abundance on yield and cost under full-cost models, the relationship between cost and lean uranium abundance was calculated, and the best economic lean uranium abundance under different models was solved. The technical feasibility of reducing costs by adjusting the lean uranium abundance was analyzed, and suggestions for production adjustment of uranium enrichment plants were put forward. Through the research, the optimal lean material abundance under the full-cost mode was determined, which provides the reference for coordinating industry costs.

According to the production and management requirements of an in-situ leaching mine in Inner Mongolia, the general view diagram of the mining area and the operation diagram of the mining area were added to the host computer of the automation system, the remote parameter adjustment and alarm screen of the frequency converter were optimized, and the functions such as one key start and stop, one key given frequency were developed to realize the strict control of all links of in-situ leaching uranium production in the control and scheduling. Through the optimization of WinCC host computer, it can more intuitively display the equipment and production operation, further simplify the adjustment of instrument operation parameters, improve the working efficiency of operators and reduce production costs.

Taking the detection and control of centrifugal cascade in the first ⁷⁶Ge isotope separation project in China as the object, the hardware structure and configuration programming of DCS (Distributed Control System) were controlled to ensure the safety of the main process key equipment (the rotary stabilizer). The system realizes the real-time view of various process parameters on site, remote switches on and off the electric valve, starts and stops the vacuum pump, and adjusts the opening of the electric regulating valve on the process pipeline, which effectively ensures the safe and stable operation of the ⁷⁶Ge isotope production line.

The uranium tailings from a uranium mine in Hebei province were cured with cement and RD curing agent commonly used in the market. The mechanical properties and radon shielding properties of curing test blocks were studied, and the calculation formula for the optimal radon shielding layer was derived. The weathe rability test of the shielding layer was also carried out, and the microscopic mechanism of the curing test blocks was analyzed. The results show that the optimal mass ratio of uranium tailings curing is 0.08% RD curing agent and 15% cement. Under the optimal ratio, the compressive strength of the curing test blocks can reach 3.0 MPa, and the radon exhalation rate is 0.39 Bq/(m²·s). When the thickness of the solidified layer is 10 cm, the radon exhalation rate on the surface of uranium tailings decreases by 81.2%, and the radon shielding effect is obvious. At the same time, the radon exhalation rate on the shielding layer surface did not fluctuate greatly in the artificial simulated environment test, and the stability is good.

In order to solve the problems of poor dam stability and difficult construction of cover system caused by high water content and low strength of fine tailings, a series of field tests of the vacuum preloading method combined with prefabricated vertical drains to reinforce fine tailings were carried out. The surface settlement, layered settlement, lateral displacement, degree of consolidation and pore water pressure of tailings under different spacing of prefabricated vertical drains were analyzed, and vane shear test and bearing capacity test of tailings were conducted. The research results show that vacuum preloading method can accelerate dewatering of tailings, effectively reduce the water content, then improve the strength and bearing capacity of tailings, and the reinforcement effect of prefabricated vertical drains spacing of 1.0 m is better than that of 1.2 m. As a technology with low cost, good effect, safety and environmental protection, vacuum preloading method has a broad application prospect in in-situ dewatering and reinforce of fine tailings.