The autoclaves are important components of the high-pressure acid leach circuit on the Syerston project in New South Wales, and, according to Clean TeQ managing director Sam Riggall securing the long-lead item will significantly de-risk the project schedule, with delivery lead times in today’s market for similar equipment being almost three years.

Riggall said the acquisition of the autoclaves from Vale International was a remarkable development for Clean TeQ and the project.

The autoclaves and their purpose designed agitators, flanges and associated equipment were designed and fabricated by Coek Engineering in Belgium for Vale’s Niquel do Vermelho project in Brazil but never used.

The pressure vessels have steel shells and explosively bonded titanium lining to withstand the operating conditions required for effective leaching of nickel, cobalt and scandium, and are in excellent condition after never being in use.

Each autoclave can manage a slurry volume of 647 cubed metres, which is sufficient to achieve the required residence time for an anticipated 2.5 million tonne per annum ore throughput; and the operating slurry temperatures of 250°C and operating pressure of 4500 kilopascal gauge also stops the slurry from evaporating.

Each autoclave also comes with associated equipment including agitators, mechanical seals and seal skids.

The vessels had been sitting in storage in Rotterdam for several years before Vale shipped them to the Goro Project in New Caledonia in 2012; while the agitators and associated equipment have been stored in a customs bonded yard in Schopfheim, Germany at Ekato’s manufacturing facility since fabrication in the early 2000’s.

The autoclaves will now be shipped to Newcastle for storage until they can be transported to the Syerston project site for installation.