Vergrößerung eines luftgepulsten Misch-Absetzers für die extraaktive Wiederaufarbeitung von Kernbrennstoffen

Starting from a small scale stirred mixer-settler a bench scale air-pulsed mixer-settler without moving parts is developed . A few preliminary tests demonstrate that it can be used in the JUPITER pilot plant, which is to be built for the reprocessing of the thorium containing nuclear fuels. To derive scale-up criteria of this mixer-settler model experiments are male of the mass transfer in the mixing chamber, the phase separation characteristics in the settling chamber and the transport of fluids through a mixer-settler stage using two apparatus of different size. With the aid of the similarity theory a mass transfer equation is formed, which enables the size of the mixing chamber and of the pulsing tubes as well as the operation datas of the pulsing equipment to be caIculated. The settling process is described by a model of coalescence, which is used to determine the area of the settling chamber. At last the theory of the hydrodynamic Balance yields to the conditions causing the transport of both liquid phases through a mixer-settler battery. Regarding the necessary criticality safety in a nuclear reprocessing plant the size and operation datas of an air-pulsed mixer-settler are calculated for the throughput of a prototype plant