Mandalay Resources is a Canadian-based natural resource company with mines in Australia (Costerfield) and Sweden (Björkdal).
The Costerfield operation is located within the Costerfield mining district, approximately 10 kilometres northeast of the town of Heathcote, Victoria. It’s involved with extracting gold and antimony – and is the only mine in Australia to do so.
Antimony is a semi-metal that is used in the electronics industry and alloyed with lead or other metals to improve their hardness and strength. Current annual production is approximately 50,000 gold ounces and 4000 antimony tonnes.
The mining method employed is long-hole stoping with cemented rock fill. The stopes are subsequently backfilled with cemented rock fill to supply stability, reduce dilution, and allow for mining above and below developed levels.
The cemented rock fill is produced by mixing the cement powder with water which creates a paste to which waste rock from the mine is added – a great example of a waste product being recycled and repurposed for another use. The whole process takes place underground in the mine.
An issue with tipping the cement prior to mixing was the catalyst for site foreman Tony Gready to look at and ultimately purchase a Flow-Easy vibrator from Melbourne-based vibration equipment specialist Enmin.
“Concrete powder when placed in the spreader body tends to flow in – it levels in much the same way as water. Because of the angled side of the fertiliser spreader body we found that a lot of the powder would get stuck up on the sides when we were extracting,” Gready said.
“The only solution was to bang on the side or use shovels – an absolute pain of a process and time consuming. Each load is around 5 tonnes and we were finding that around 700kg was left in the tub. This residue would then be transported back up which was obviously very wasteful and unproductive,” he added.
The manufacturer of the spreader body suggested that a solution could be the installation of a vibrator and recommended contacting Enmin.
The Flow-Easy vibrator range includes 12- and 24-volt electric models along with hydraulic and pneumatically powered options that are ideal for transport applications that require vibration to be applied for an extended amount of time. If required, they can be run continuously, rather than the more generally utilised intermittent operation of the electric models.
After discussion with Enmin sales manager Paul Leahy, a suitable electric vibrator was selected. Armed with operating and installation instructions from Leahy, the vibrator was fitted on the side of the spreader body by Gready’s boiler maker.
The result was something of a Eureka moment.
“The electric vibrator quickly cleared all the powder out of the tub in just a matter of seconds. We don’t need the vibrator working for an extended period of time so we had a button fitted which allows for intermittent short bursts. That’s all that is needed to get the tub completely emptied. Our tipping problems were solved immediately,” Gready said.
“The vibrator has minimised wastage, reduced operator workload and ultimately improved our productivity. It’s worth its weight in gold,” Gready summed up.
For info on the Flow-Easy vibrator, visit floweasy.com.au.