Asanko Gold’s mine in West Africa has significantly improved efficiencies after an advanced milling control system was installed using the MillSlicer instrument.
Asanko is a large scale, multi-pit asset located on the Asankrangwa belt in Ghana. Built in 2015 by engineering contractor DRA Global, first gold was poured in January 2016 and commercial production got underway in April 2016.
With Asanko focusing on efficiencies, the mine aims to prevent unplanned or forced mill stoppages, which often leads to costly setbacks for overall mine operations. Therefore, the mine collaborated once again with DRA Global’s technical processing specialists to develop a control system solution capable of producing real time reporting and that enables the mill operators to better optimise the milling process.
According to Val Coetzee, DRA’s senior vice president, the MillSlicer control instrument provides accurate signals via a number of strategically positioned vibration sensors that are used by DRA’s comminution and control specialists to develop a bespoke control system, specific to an operation. “The programme allows for accurate mill charge toe-angle measurement and real time polar plot determination, which is used in the customised control system,” Coetzee explains.
The milling control system, which was commissioned by DRA in August 2018, uses propriety ‘rule-based algorithms’ which assist the mine’s operation with superior control, maximising energy efficiency and ensuring continual optimal mill performance despite any changes in mine fragmentation or ore type variances.
“DRA is able to provide remote operational support, data analysis and reporting to assist clients in reducing liner damage, media consumption and ensure that mill operators efficiently maximise throughput at all times,” says Coetzee.
This MillSlicer hardware and the DRA Advanced Control System, in conjunction with a number of other initiatives relating to open circuit modifications, use of cameras and feed blending, have successfully contributed to the performance excellence of the Asanko processing plant in recent months.
According to Russell Bradford, SVP Metallurgy at Asanko, the MillSlicer hardware has enabled the Asanko team to optimise the mill’s performance by ensuring the team always has the right blend of ore at the right tonnages in the mill. Since this technology was implemented, the Asanko processing plant has consistently delivered above its five million tonnes per annum design rate,” says Bradford.