PROJECTS

The ROX GOLD SEGUELA Gold Mine is situated 550KM northwest form the capital of Ivory Coast, ADIJAN, in the Woroba province.

The mining and processing are operated by Rox Gold and the ore is mined using the conventional open-pit method of drill and blasting.

The ore is then transported with trucks to the primary crusher, the crusher out loading conveyor feeds the crushed ore to the SAG (semi autogenous grinding) milling comminution circuit.

The SAG mill was designed and build by the MO group with a thru put of 156T/Hr.

The SAG Mill is power with a Siemens 6Pole Double Stator Squirrel cage Induction motor with a power rating of 6500KW, the speed of the motor and SAG mill can be adjusted by means of the SIEMENS GM150 Water Cooled Variable Speed drive.

The Sag mill is started at a low speed of 5% by means of the main motor and variable speed drive for one complete rotation of the Sag mill drum to ensure that there is not a suspended charge in the mill drum.

After completion of the initial single rotation the mill motor is ramped up to synchronize speed with a time constant of 90s.

There are two closed water circuits for the cooling of the GM150 power conductors, the cooling medium of the primary circuit demineralized water that is pumped through the VSD internals, the water-to-water heat exchanger is used to cool the primary water whiles a water chiller is used to cool the secondary water.

Plant specifications:

• Supply Voltage  :  11KV
• VSD Supply Voltage  :  4,6KV
• VSD Max Output Current  :  1600A
• Motor Voltage  :  4KV
• VSD Rectifier Topology  :  24 Pulse Rectifier
• VSD Inverter Topology  :  3-Level Neutral Point Clamping