Speaker
Description
The Element Fuel Experimental Installation (EFEI) is an installation equipped with a Pilot Conversion Plant (PCP) facility designed to convert and refine yellowcake powder (U3O8). Yellowcake (U3O8) powder is converted into nuclear-grade uranium dioxide (UO2) powder as the main component of making nuclear fuel. The yellowcake conversion process includes dissolving yellowcake, purifying uranyl nitrate solution, concentrating uranyl nitrate solution, precipitating uranyl nitrate to ammonium diuranate (ADU), drying ADU, calcining ADU powder to U3O8, reducing U3O8 to UO2 and passivation. The Pilot Conversion Plant (PCP) facility is designed to convert and refine yellowcake powder (U3O8) with a design production capacity of 100 kg of nuclear-grade UO2. Each batch process at the PCP facility is expected to produce liquid waste that may contain of uranium. Waste containing uranium still requires further processing to retrieve the uranium contained in the waste before being sent to the Nuclear Waste Treatment Plant. For this reason, processing is needed to reduce the concentration of uranium in liquid waste by the precipitation method. The precipitation method is widely used because it is relatively cheaper and simpler. The research was conducted with several variations including reagents, pH, reagent volume and reaction time. The reagents used were NaOH, KOH, NH3 solutions, NaH2PO4 and KH2PO4. The concentration of uranium in the wastewater before and after the precipitation process was analyzed using ICP-OES and the precipitate was characterized by SEM-EDS and XRF. Sample test data were analyzed to determine the decrease in uranium concentration in PCP liquid waste, Ksp value, uranium precipitation reaction rate and the character of the resulting precipitate.
