Speaker
Description
Technologies for the management of radioactive waste has been constantly upgraded based on R&D activities and operating experience with a view to minimise the release of activity to the environment, reduction in the volume of waste disposed, its recycle and reuse and to lower the radiation exposure to the operating personnel. An important effluent coming from uranium refining operation is ammonium nitrate solution as Ammonium Di-Uranate Filtrate (ADUF) during refining process of uranium for fuel fabrication. The significant volume of nitrate solution needs to be processed after decontamination for efficient effluent management. Since present day safety and environmental issues are becoming increasingly stringent, the discharge of nitrate bearing effluent is now turning out to be much more serious concern. Hence, for achieving a cost-effective waste management, it would be a novel approach to recycle this effluent and explore the utilisation of this waste product in other processes or applications.
Efforts have been made to utilise this effluent for volume minimisation by recycling it in uranium processing routes itself. The effluent ammonium nitrate was recycled as a strippant for stripping uranium from loaded solvent (30% TBP) during solvent extraction in place of De-Mineralized (DM) water. Extensive studies were performed to find the optimum stripping conditions through countercurrent batch simulation for quantitative and qualitative uranium recovery. Plant scale implementation of the process leads to almost 40% reduction in the volume of nitrate waste and its effective utilization in the in-situ process. Thus, the value addition by such kind of improvisation in these waste recycling strategies with scientific inputs, has made a wholesome contribution towards the mitigation of the challenging problem of the nitrate waste management in uranium refining plant.
