Title: Selective recovery of heavy metals from hot-dip galvanising effluent streams by membrane-based solvent extraction

Authors: Sam Cook, Sandra Kentish, Jilska Perera, Geoff Stevens, Peter Hetherington

Addresses: Particulate Fluids Processing Centre, Department of Chemical and Biomolecular Engineering, The University of Melbourne, Victoria 3010, Australia. ' Particulate Fluids Processing Centre, Department of Chemical and Biomolecular Engineering, The University of Melbourne, Victoria 3010, Australia. ' Particulate Fluids Processing Centre, Department of Chemical and Biomolecular Engineering, The University of Melbourne, Victoria 3010, Australia. ' Particulate Fluids Processing Centre, Department of Chemical and Biomolecular Engineering, The University of Melbourne, Victoria 3010, Australia. ' Suminko Pty. Ltd., 45 Grove Crescent, Toowong, Queensland 4066, Australia

Abstract: The hot-dip galvanising process produces a large quantity of acidic effluent high in iron, zinc and chloride ions. The current method for disposal of the waste acid is to neutralise the remaining hydrochloric acid (HCl) to precipitate a worthless, environmentally harmful mixture of iron and zinc hydroxides that be disposed of to specialised landfill sites. The recovery of any of these species is of economic interest due to the minimisation of waste-transport costs and the recovery of saleable by-products. In this work, a membrane-based solvent extraction process is being developed for the selective recovery of zinc over iron. Using a laboratory scale hollow fibre contactor, the key operating parameters including feed and organic flow rates, as well as their position within the contactor (shell or tube-side), are being systematically analysed. The results of the project should provide sufficient process information to permit the construction of a pilot scale effluent treatment process.

Keywords: heavy metals; hot-dip galvanising; solvent extraction; waste management; effluent streams; effluent treatment; acidic effluent; zinc recovery; iron chloride recovery.

DOI: 10.1504/IJW.2007.016323

International Journal of Water, 2007 Vol.3 No.4, pp.407 - 417

Available online: 17 Dec 2007 *

Full-text access for editors Access for subscribers Purchase this article Comment on this article