TORONTO (miningweekly.com) – Swiss power and automation technology group ABB on Thursday said it had commissioned an upgrade to Vale's existing Clarabelle dual pinion semiautogenous grinding (SAG) mill, in Sudbury.
The mill is used to reduce the size of the ore at the company's nickel and copper mines in the Sudbury area.
Located about 400 km north of Toronto, Vale's Sudbury operations, in Ontario, were mainly underground nickel sulphide mines with integrated mining, milling, smelting and refining operations.
ABB reported that the project was completed on time and on budget.
The firm noted that one of the characteristics of Clarabelle mill is to accept nickel/copper ore from various sources and companies and to produce a nickel/copper concentrate and copper concentrate for further processing. The size of the ore is further reduced in SAG mills, rod mills and ball mills, where all milling is done wet.
First awarded in 2010, the project was the largest of several turnkey projects completed for Vale in Canada. ABB said that the complex project involved an upgrade to a SAG mill of 10 m in diameter, and 11.2 revolutions per minute that had reached the end of its useful life, with a newer, more robust system.
ABB replaced all of the electrical equipment, including 5 500 KW motors, converter, transformer, motor control centres, switchgear and mechanical auxiliary equipment, such as the cooling system - pump skid, chillers and fin-fan heat exchangers.
The company also modified the existing foundation and air clutch coupling to adapt it to the new motors. A number of SAG mill applications were implemented to facilitate the operation and maintenance of the SAG mill.
ABB also built an additional structure next to the existing mill to house all the new equipment and integrate its system with the mill. Engineering and construction of the building extension included excavation, foundation, civil, structural steel and architectural works as well as insulation, fire system, lighting, heating, ventilation and air conditioning.