Investigations of spouted bed electrowinning for the zinc industry

Research into potential applications of spouted bed electrowinning (SBE) in the zinc industry was conducted, in a collaboration between our two organizations. The main system investigated was zinc from acidic sulfate electrolytes. However, SBE can be extended to other electrolytes, or recovery of other elements. Electrolytic tests were carried out at the 0.01 to 0.1 in 2 scale. Spouting behaviour has been studied at a larger scale, approaching a size suitable for an industrial unit cell. Much of our work was carried out using a micro-porous separator (Daramic(R)). However, we have also shown that ion exchange properties can have a controlling effect on the process chemistry, electrochemical efficiency, and plant flowsheet. In initial 0.1 in 2 scale electrolytic tests, design and engineering issues for scale-up were identified. We review the major achievements, promising areas for application in the zinc industry, current status, and remaining barriers to development of SBE technology.