Evaluation of Uranium-Removal Characteristics From Soil-Washed Wastewater Using Precipitation Methods

다국어 초록 (Multilingual Abstract)

Uranium-contaminated soil can be effectively decontaminated through acid leaching; however, this process process gen erates significant amounts of radioactive wastewater. Therefore, developing efficient methods to remove uranium from wastewater is essential to minimize radioactive waste generation. This study investigates the applicability of various pre cipitation methods for uranium removal from acidic wastewater produced during soil-washing processes. Three methods were evaluated: metal hydroxide (M–OHx ) co-precipitation, uranium peroxide (UO4 ) precipitation, and uranium phos phate (KUO2 PO4 ) precipitation. The M–OHx precipitation method removes uranium by precipitating excess metal ions in wastewater by adjusting the pH. This method is easy to use and has a high removal efficiency. The UO4 and KUO2 PO4 precipitation methods involve adding reagents to precipitate uranium in the mineral phase. They enable selective uranium separation and further volume reduction. In the results, M–OHx and KUO2 PO4 precipitation methods remove uranium to less than 1 mg∙L−1 within 2 h, demonstrating superior capabilities compared to UO4 precipitation. The optimal method is different depended on the management strategy for the recovered uranium. The M–OHx precipitation method was suitable for permanent disposal, whereas KUO2 PO4 could be recycled. Based on these findings, guidelines for the effective treat ment of wastewater containing uranium from the soil-washing process can be established.