ONLINE LIBRARY

Edited by: V. Papangelakis and M. Collins

Proceedings from the 34th Annual Hydrometallurgy Meeting on Pressure Hydrometallurgy FOREWORD

Pressure Hydrometallurgy 2004 is the 34th in an annual series of meetings organised by the Hydrometallurgy Section of the Metallurgical Society of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM). The goal of these meetings is to bring together scientists and engineers representing metal producers, equipment suppliers, engineering firms, test laboratories and academia from around the world to share knowledge and exchange ideas. The topics of previous annual meetings have been wide-ranging in the field of hydrometallurgy, yet the application of autoclaves to solve metallurgical problems has frequently been described in papers at these various meetings. This is the first Annual Hydrometallurgical Meeting where the pressure vessels themselves and the processes operating therein have been chosen as the central topic for discussion.

Pressure hydrometallurgy is an exciting and advancing technology. Processes operating at high temperature and under pressure enjoy fast kinetics, enhanced selectivity over iron and other diluent species, enhanced solubilities of reagent gases, and more stable residues as compared to atmospheric processes. The drop in the dielectric constant of water with temperature and the associated enhancement in metal-anion bonding offer new possibilities to explore in terms of metal extraction selectivities. Pressure vessels have been commercially used for the extraction of aluminium, nickel, cobalt, uranium, and copper; the oxidation of refractory gold feeds; and the purification and recovery of various metals and metal by-products. In recent years, new processes have been explored in base metals, light metals, precious metals, and rare earths that involve pressure hydrometallurgy. Significant advances have been achieved in fundamental chemistry and new ideas have been tested in sensor development. New construction materials and corrosion-resistant alloys have been produced, and autoclave design improvements have been conceived. The papers presented in these proceedings describe a wide range of applications covering the above topics, as well as test programs and scoping studies in areas that have yet to be commercialised.

Looking into the future, we hope that this conference will catalyze further the advancement of knowledge in Pressure Hydrometallurgy and assist in the design and implementation of even more efficient processes.