Simultaneous removal of oil, total Co and 60Co from radioactive liquid waste by dissolved air flotation

This report presents a kinetic study of the simultaneous removal of oil, total cobalt and 60 Co from radioactive liquid waste by dissolved air flotation. We studied the effects of the incorporation of an inclined lamella module in the flotation cell on the overall removal efficiency. The results showed that the removal of oil is greater than the levels observed in the total cobalt and 60 Co. It was established that the removal of Co depends on the oil’s separation. This finding is explained by the chemical behaviour of Co, as well as the physico-chemical characteristics of the liquid residue. However, the evidence showed that the efficiency of the dissolved air flotation system with the inclined lamella module is greater than the conventional dissolved air flotation system. In addition, the comparison between the efficiency and the value of the kinetics constant θ showed that they share a directly proportional relationship. Finally, it was established that the kinetic constant θ estimation through the kinetic equation represents a simple way of assessing and controlling the dissolved air flotation process.