Thursday, 28 July 2016
Tim Napier-Munn emailed me earlier in the week with this remarkable photograph of roughly one half of the line of 28 ball mills in closed circuit with rake classifiers at the Mufulira copper mine, Zambia, in the 1970s.
The concentrator treated 20,000 tpd, which makes about 30 t/h per mill but that’s without circulating load.
Tim asks if anyone remembers the total throughput of each mill including the circulating load.
The current largest mill in the world (AG) treats 1350 t/h of hard ore so basically Tim is trying to assess how many of these small mills this is equivalent to. Although he realises that it is probably not fair to compare ball vs AG and medium hard vs hard, he is trying to make a point about how much increase in scale there has been in our professional life time.