The opinions here are solely those of MEI's Dr. Barry Wills (www.linkedin.com/in/barrywillsmei), author of Mineral Processing Technology, Founding Editor of Minerals Engineering.
"MEI is the glue that holds the minerals industry together" (Prof. John Ralston, South Australian Scientist of the Year).
Saturday, 22 October 2016
Comminution in the mid 21st century - will SAG mills still be relevant?
This is the question which will be posed by Prof. Holger Lieberwirth of TU Bergakademie Freiberg, Germany, in his keynote lecture at Comminution '18 in Cape Town.
What are your views? Will SAG mills still be relevant in 50 years time?
Bary, I am happy that a talk by Prof.Holger is being planned on such an important topic. Let me express my views--I feel we may have to look at the topic as "for what kind of ores and for what sizes with which inherent characteristics should one be thinking nothing but Sag Mills for better reduction ratios with lower power/water/space/capital costs" My phrasing may be clumsy but I am sure Prof.Holgers talk will look at the isuue in totallity. Rao,T.C.
As a seller of grinding media I would like to say yes, especially with ever dwindling head grades necessitating increased throughput to maintain metal units, however I can picture a shift towards pre-comminution concentration in the future. This shift will likely result in a reduction in the hardness of the material feeding the mill, so I am not sure whether SAG milling will remain as popular as it is now. I would not be surprised to see many of these SAG mills being converted to AG mills if pre-concentrating becomes common practice. Besides, it seems that HPGR are proving themselves a excellent alternatives for many applications and many operations seem capable of achieving target throughput and grind size/liberation using a single stage of milling. While it is true that more grinding lines are required for the same throughput if only primary ball mills are used (larger foot print/more capital/more equipment), this typically gives the plant much more flexibility and less downtime.
Bary,
ReplyDeleteI am happy that a talk by Prof.Holger is being planned on such an important topic.
Let me express my views--I feel we may have to look at the topic as "for what kind of ores and for what sizes with which inherent characteristics should one be thinking nothing but Sag Mills for better reduction ratios with lower power/water/space/capital costs"
My phrasing may be clumsy but I am sure Prof.Holgers talk will look at the isuue in totallity.
Rao,T.C.
As a seller of grinding media I would like to say yes, especially with ever dwindling head grades necessitating increased throughput to maintain metal units, however I can picture a shift towards pre-comminution concentration in the future. This shift will likely result in a reduction in the hardness of the material feeding the mill, so I am not sure whether SAG milling will remain as popular as it is now. I would not be surprised to see many of these SAG mills being converted to AG mills if pre-concentrating becomes common practice. Besides, it seems that HPGR are proving themselves a excellent alternatives for many applications and many operations seem capable of achieving target throughput and grind size/liberation using a single stage of milling. While it is true that more grinding lines are required for the same throughput if only primary ball mills are used (larger foot print/more capital/more equipment), this typically gives the plant much more flexibility and less downtime.
ReplyDeleteMichael Myllynen