Criticality Safety Calculations of ‘Poison Tube Tank’ Compared with Annular Tanks for Storing Fissile Solutions

Abstract

A comparative study of the shielded area space required for storing fissile solution by the conventional annular tank and by poison tube tank is made. Poison tube tank is similar to commercial heat exchanger. The neutron poisons studied are gadolinium oxide and borax. Variation of multiplication factor for an array of annular tanks containing uranium nitrate or plutonium nitrate solutions are presented for annular widths of 10, 7.5 and 5 cm. It is concluded that for the given concentration, 5 cm annular width tanks are safe at a pitch distance of 120 and 90 cm for uranium and plutonium solutions respectively. Using these, as reference values, it i5 found that the shielded area saving for the poison tube tank is a factor of 12 and 8 for the given concentration of uranium and plutonium solutions respectively.