Preliminary design and cost considerations for a plant to produce nuclear purity uranium dioxide from Australian ore concentrates

Abstract

Design considerations are outlined for plants for the production of nuclear purity uranium dioxide with capacities of 100, 200 and 500 tonnes U/year. The cost of the process equipment is not greatly affected by various process alternatives; equipment performance, which affects product quality, consistency of power properties and plant reliability, is important in determining the recommended process. This involves the following steps: batch dissolution, continuous solvent extraction in mixer-settlers, single-stage precipitation of ADU, thickening and spray drying of ADU, and calcination-reduction in continuous pulsed fluidised bed reactors. Estimates of the cost of recovery of free acid and combined nitrate from the raffinate and filtrate waste streams indicated that the value of the recovered acid would be greater that the processing cost only in the case of free acid recovery from solvent extraction raffinate in the 500 tonne/year plant. However if acid recovery is necessary for plant effluent control, the processing cost can be largely offset by the value of the recovered acid.