Masurca waste

The Masurca waste exhibits the special property of high UO concentration (12 g/L), so that the first operation to be performed is TBP extraction of U(VI). This operation does not require prior feed adjustment, because the acidity and nitrate ion concentration are sufficiently high. The U(VI) concentration of the PuOprecycle waste,even after volume reduction by a factor of 50, does not require a specific uranium extraction cycle. 

The technique employed almost exclusively in the process developed is extraction chromatography (LLC), which is an ideal technique, in view of the column exchange capacities, for the extraction of moderate amounts of material present in a limited volume, or for the recovery of elements present in low concentration in large volumes. The simplicity of the equipment and the low sensitivity of extraction performance to fluctuations in solution throughputs make it a simpler technique for use than liquid-liquid extraction. Moreover, LLC lends itself well to discontinuous operation. In the case of difficult separations, such as Am/Cm separation, LLC offers the advantage of a large number of stages in a simple, compact unit. Since the extraction of the U(VI) present in the Masurca waste in macroconcentration is not economically feasible by LLC, the conventional liquid-liquid technique was adopted. 

Process flowsheets. The flowsheets of the chemical processes used for the treatment of Pu/Al targets and the Masurca waste were described recently ( , 23), so that we shall only discuss the major principles here. However, we shall dwell in greater detail on the process flowsheet adopted for treatment of the waste produced by the recycling of Pu02 scrap, which is expected to go on stream in August 1980. 

Treatment of Waste Solutions containing Americium. The process flowsheets developed to treat Masurca waste and the solution from recycling of Pu02 scrap are presented in Figure 6. Treatment of the Masurca whste is complex and requires the following steps. 

The major drawback of the processes described here obviously lies in the generation of liquid wastes heavily loaded with nitrates salts, thus complicating their subsequent management. For some wastes, it is impossible to avoid this high salt concentration. In the case of the treatment of Pu/Al targets, these wastes contain the fission products their salt concentration (Al +) is imposed by the nature of the target. For the Masurca waste, the initial solution is already heavily loaded with nitrate salts. 

The active "Masurca" solution (Table II) is a special type of waste resulting from the reprocessing of certain irradiated fuels and from criticality analyses. 

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