Corem sounds the “death knell” of ball milling
by CM Staff
Ball milling is responsible for approximately five per cent of the total cost of metal production and one per cent of the world's total energy usage and carbon emissions.
QUÉBEC CITY— Corem has partnered with the University of British Columbia, two mining companies and six equipment manufacturers to establish high-pressure grinding ahead of mineral separation as an alternative to wet ball milling.
The group will present their developments at the 2022 industry technical conferences, SME in Salt Lake City and CIM in Vancouver, according to a company statement.
Corem explained that in the mining world, wet ball milling is notorious for being inefficient as it requires high levels of energy. Ball milling is responsible for approximately five per cent of the total cost of metal production and one per cent of the world’s total energy usage and carbon emissions.
The company said it used plant data and samples needed for pilot plant testing from two milling operations, a small gold ore processor and a large tonnage copper ore processor.
After planning and preliminary equipment testing, pilot circuits using high-pressure grinding rolls, closed circuited with sizing screens, were run in batch-locked cycle style to steady state conditions.
Some of the key findings from the study were as follows.
- HPGR energy consumption (kWh/t) was 38 per cent of the ball mills, 62 per cent lower.
- With all the different auxiliary equipment, HPGR total circuit energy usage was still less than 50 per cent of the ball mill circuits.
- Fines removal from HPGR feed increased grinding efficiency in the compression zone by 25 to 30 per cent.
- There was no excessive fines production with HPGR. Micro-cracking was greater, and downstream processing was similar or better.