In late 2015, EPSA’s Kalgoorlie Rental team was contacted by Minara Resources to provide a competitive quote for power generation supply to its Murrin Murrin nickel cobalt site in Western Australia’s north-eastern goldfields.
“Our initiatives, proven cost efficiencies and broad capabilities for service were integral to our success for the three-year contract to run from October 2015 to October 2018,” says Paul Walter, EPSA’s Regional Rental Manager – West.
“Our contract is to supply 20–2,000 kVA power generation to the entire Murrin Murrin site including for outages, planned shutdowns and maintenance. There is also a bi-annual requirement for 12 MW of temporary power for the main power station during shutdown maintenance, a process that can last for up to three months.
“During planned shutdowns, the site’s acid converter plant must be cooled down. It generally operates at around 400 degrees Celsius but during
the shutdown the temperature drops to approximately 150–200 degrees Celsius over a number of days,” explains Paul.
“Historically, extraction fans have been used for airflow but our technician discovered that this process actually provides airflow and moisture to the catalyst, which makes it active and thus increases heat. We proposed a solution that was key to demonstrating our expertise – to add glycol to run lower temperatures, remove moisture and negate the freezing-up of coils overnight in order to speed up the shutdown process by a few hours.
“The cooling solution that we provide drops the temperature to 50 degrees Celsius over a 14-hour period, providing
cost efficiencies with significantly less downtime. We have done this with the supply of Cat® generators and temperature control products including PM 1500 generators and one additional 810 kVA generator for eight months. We are also supplying an acid converter cooling package consisting of Cat 600 kVA generator, 700 kW chiller, two 450 kW air handler units, pump, buffer tank, cables, ducting and other ancillary requirements.”
Minara Resources is one of Australia’s top nickel producers. They use open-pit mining techniques followed by ore processing (comprising pressure acid leaching, mixed sulphide precipitation, cobalt refining and nickel refining). Ammonium sulphate is also produced as a by-product.