Prof. Noel Warner: 1932-2022

I heard rather belatedly a few days ago of the death of Prof. Noel Warner, on April 14th at the age of 90.

Noel Warner was Emeritus Professor of Minerals Engineering at the University of Birmingham, UK. I got to know this genial Australian very well in the late 80s and early 90s when he was external examiner for the mineral processing degree at Camborne School of Mines. He was President of the Institution of Mining and Metallurgy, 1992-3.

Amanda Wills with Noel Warner at the 2010 IMPC in Brisbane

He used to talk passionately of the process that he and his team at Birmingham were developing for the treatment of polymetallic massive sulphide deposits. The process was direct ore smelting. What was to become known as the Warner Process (Minerals Engineering Vol. 2 Number 1, 1989) was radical, in that the ore was smelted in a single furnace, the enormous amount of energy required to do this being recovered from the molten slag. Expensive comminution was avoided, apart from some preliminary crushing, and the inefficient flotation step was also by-passed. Pilot plant runs using McArthur River ore showed that zinc and lead recoveries could be well over 90% and with the adoption of innovative energy recovery technology, the thermal requirements could be satisfied by the inherent energy content of the ore itself. The Birmingham team showed that the energy requirements of direct ore smelting could be competitive with conventional mineral processing, particularly for ores containing sulphides.

Noel got a pilot plant built and operated at the University of Birmingham and demonstrated that the closed circuit could be worked on a big scale, and a number of people were attracted to come and see it, but enthusiasm was not overwhelming. Maybe it was too radical an innovation to be thrust on what was then a very conservative industry?

It's a shame that Prof. Warner never saw his process adopted commercially. It is certainly novel and operating at around 1000C the processing dynamics are very fast compared with flotation and electrowinning.

I have no doubt that comminution and concentration techniques will continue to evolve, but will there be a time when they lose the battle, when the remaining ores are so finely disseminated and intergrown that they can no longer be treated by physical methods? Is no mineral processing the future of mineral processing, and will the future be direct hydrometallurgical and pyrometallurgical routes? Maybe one day Prof. Noel Warner will be remembered for his unique invention.

@barrywills