Mill Optimisation - Increased throughput from liner design initiatives in the Aktogay 40 ft sag mill

This paper outlines a basic, but simple approach and the benefits of having the key stakeholders collaborate and focused on using advanced methods and technologies to identify and incorporate mill liner design initiatives to maximise the performance of key critical equipment. Here we have shown the benefits focused on the large 40 ft SAG mill at Aktogay to not only optimise the mill lining in the mill, but to achieve the KPI milestones in operating performance, maintenance improvements, reline safety, and future design initiatives.

The 40 ft SAG mill was supplied with a traditional bi-directional OEM lining system manufactured from chrome molybdenum steel with a total of 412 liners per set and a total liner mass of 773,931 kg. All the liners were designed and installed utilising a 4,500 kg 7-axis Russell reline machine. The SAG mill was inspected on a regular basis to monitor the change in liner design and identify wear patterns to gauge the mill performance as the circuit ramped up production over the first set of liners.

The first commissioning set of liners were removed during September 2017 producing a total of 8,518,545 tonnes, at its peak average 2,034 t/h. A review of the first set of mill liners quickly identified areas in the liner design that would enhance the wear life of the liner set, increase discharge throughput efficiency, improve the mill reline times, focusing on reducing overall maintenance costs, whilst keeping safety at the forefront of all decisions, ultimately working towards achieving the original target tonnes. 

The continual improvements made to the operation and the initiatives presented through the new liner design has seen Aktogay achieve their target mill throughput performance of 3,102 t/h. The collaborative approach has delivered improvements in performance across all key indicators whilst operating in a safe environment.