Pilot Test of Automated U-shaped Ion Exchange Facility

The escalating demands for efficient uranium extraction and environmentally sustainable mining practices underscore the need to address the inefficiencies in conventional acid in-situ leaching processes. Traditional methods often suffer from low uranium recovery rates, high operational costs, and significant raw material wastage, necessitating the development of more effective and sustainable alternatives. Conventional dense moving bed techniques, widely used in uranium hydrometallurgy, are often associated with complex workflows, high operational costs, and substantial resin losses. These inefficiencies collectively diminish uranium leachate extraction efficiency and increase resource wastage, making the process less viable in modern mining operations. To overcome these limitations, and improve uranium recovery efficiency, reduce operating costs, and minimize raw material consumption in uranium mining, a new DN600 U-shaped ion exchange facility was designed, and saturated resin re-adsorption and elution were integrated into a single apparatus in this paper. Experimental trials were conducted under controlled laboratory conditions to fine-tune critical process variables, including the linear velocity of the elution agent, resin cycle duration, and liquid-solid separation ratio. Their impact on process efficacy, uranium recovery rates, and overall economic viability was rigorously assessed. Through extensive optimization, the optimal operating conditions are obtained which are eluent linear velocity of 1.8 m/h, resin cycle duration of 2.5 h, and liquid-solid separation ratio of 19%. Under these conditions, the maximum resin processing rate of the U-shaped ion exchange facility is 0.28 m³/h. The uranium concentration in the enriched eluted solution is 43-50 g/L, making it suitable for direct precipitation, while uranium concentrations in the stripped liquid are effectively reduced to 1.2-2.2 g/L, ensuring minimal uranium loss and efficient resource utilization. Compared with traditional uranium hydrometallurgy technology, the uranium recovery efficiency of U-shaped ion exchange facility is significantly improved, while operating costs are reduced by reducing the consumption of resin and eluent. Moreover, it exhibits consistent performance across multiple operational cycles, confirming its long-term stability and reliability. The improvements stem from its integrated design, which minimizes resin loss, simplifies workflow, and reduces both downtime and maintenance requirements. Furthermore, the environmental benefits of this approach are noteworthy, as the process decreases waste liquid volumes and reduces raw material inputs, aligning with sustainable mining objectives. The above results indicate that the U-shaped facility provides a robust, cost-effective, and scalable solution for acid in-situ leaching, with great potential for industrial scale implementation.