Multotec Process Equipment’s spiral technology has recently enjoyed success at copper mines in the Democratic Republic of Congo, Zambia and Zimbabwe, the company says.

The South Africa-based company says its equipment is upgrading product from 1-3% Cu run-of-mine to 20%-plus Cu concentrate.

“These mines can achieve an upgraded product which can be sold as copper concentrate,” Graeme Smith, application engineer at Multotec Process Equipment, says. “Spirals can also be applied as a bulk reduction strategy to achieve a higher-grade material for more efficient leaching.”

Smith says this is a fraction of the mining companies benefitting from such technology.

“A number of customers mining minerals such as copper, lithium, tin and tantalite are already benefiting from using spirals to upgrade the value of their concentrate, either replacing their conventional processing technique or augmenting it,” said Smith.

He says spirals are proving their worth in helping producers become more efficient, potentially raising output levels while holding down the cost involved in downstream processing.

“This upgrading of the value of mined material also contributes to lower transportation costs and higher revenues earned,” the company added.

Working with tin producers in countries including Morocco, the DRC and Spain, Multotec spirals have been able to raise initial head grades of 1-3% Sn to levels of over 50% Sn in concentrate, according to the company. Treating tantalite from a tailings operation in the DRC, spiral technology has also performed massive bulk reduction and upgrading, while shaking tables clean the final product.

“This allows existing downstream processes to become more productive, and to ramp up production by maximising recoveries and reducing rand per tonne costs,” Smith says.

In test work in its extensive Spartan manufacturing and research facility near Johannesburg, Multotec has also succeeded in separating elements of lithium using spiral technology, aiming for 80% concentration of the element petalite, it says.

Smith highlights the value of the company’s experience in modular plants, allowing spiral applications to be conveniently containerised for transport to and commissioning at remote sites.

“Our mobile plants – capable of treating 20 t/h – can be moved in two standard containers – one of 12 m in length and the other of 6 m,” he says.