Slide Background
Slide Background

STABILISATION OF PRODUCT QUALITY AT YARWUN ALUMINA REFINERY

Denis R Audet, Rebecca Little, Neil J Hofstee

The Yarwun Alumina refinery was commissioned in 2004 by Rio Tinto in Gladstone with an innovative design that significantly reduced the capital cost and allowed above 86g/L productivity. Since start-up, maintaining acceptable product quality had been a major challenge. A collaborative project between the refinery and Rio Tinto Alcan’s Technology organisation was initiated in early 2008 to address this challenge. After a detailed analysis of the circuit dynamics was completed a number of strategies were found. Some of these strategies were trialed and implemented. The result was acceptable and considerably more consistent product, while a large capital cost solution was avoided. The outcome was largely attributable to Rio Tinto Alcan’s long history and expertise in precipitation control circuit design and control philosophy. Once a final control strategy was put in place, product quality dramatically improved, from 50% size compliance to 100% output on specification.