Boosting Efficiency: how Magoload increased SAGmill throughput and stabilized operations

An iron ore concentrator in the USA aimed to increase SAG mill throughput to reduce the milling hours required to meet their business plan. They operate multiple SAG mills and can rest some as needed if the downstream balls mills are at capacity. The plant engineers sought to
improve the size gradient of the SAG media to improve grinding efficiency, thereby increasing throughput without compromising the grind.

Historically, the SAG mills were charged once per shift or less, resulting in an inconsistent ball charge in the mill. The SAG mills were very sensitive to ball charge, causing the grind to shift with each ball addition, especially if a charge was missed.

The concentrator staff agreed to try a Magoload hoping that steady ball addition would stabilize the grinding efficiency, leading to a more consistent product and increased throughput from each SAG mill.

During the 11-month trial period, the SAG mill with a Magoload experienced a throughput increase of 1.5%, while the remaining lines collectively saw a 1% decrease in thoughput. The Magoload was credited with a 2.5% throughput increase, while maintaining a stable grind. Following these results, all remaining SAG mills were fitted with Magoloads.