Siemens receives orders for the supply of electrical equipment to the value of 40 million euros for development of the Lumwana Copper Mine Project in Zambia

The Siemens Industrial Solutions and Services Group (I&S) has received orders from Equinox Minerals Limited, Canada, for the supply of electrical equipment and systems for Open-Cast mine haulage trucks, Grinding Mills and “In-Pit” electrical reticulation, required for the development of its new Lumwana Copper Mine in Zambia. The order volume amounts to around 40 million euros and the new mine is scheduled to start operating in the middle of 2008.

The Lumwana mine, which is located in the North Western Province of the Republic, will be the single largest copper mine on the African continent. Equinox plans to extract in excess of 400 million metric tons of ore during the first 20 years of operation producing an average of 169,000 tons of copper metal per year contained in concentrates for the first 6 years of its 37 year mine life. The mine also has resources containing significant quantities of Gold, Cobalt and Uranium which may also be extracted in the near future.

For transportation of the ore from pit to crushing stations, Siemens will supply the equipment required for the electrification for 27 haul trucks along with the associated in-pit trolley assist system. All trucks will be equipped with the latest AC drive technology. In contrast to conventional DC systems, the AC wheel motors remove the requirement for both commutators and brushes. This significantly reduces the maintenance and repair costs, while increasing the availability of the units. Moreover, the drive technology employed will ensure greater safety and less wear on mechanical brakes due to the availability of an electrical retarder braking system. The trolley assist system to be installed along the main ramp haulage routes allows for the trucks to draw the electricity required for the AC wheel motors in much the same way as conventional railway systems. Additional benefits derived from this system are high starting torques, and increased speeds whilst on the gradient exiting the pit, the higher speeds result in increased cycle times whilst operation on trolley realizes huge savings in diesel fuel costs.

For continuous monitoring of all mining operations, a comprehensive communication system will be supplied. The main component of the communications system is a fail safe fiber optic backbone known as an OTN (Open Transport Network). The fiber optic network will be utilized for the conveyance of all data and communication mediums associated with the mines operations, additionally, the transmission and provision of high-quality video signals (CVBS or S Video) will enable real-time viewing of all mine operations and critical plant equipment such as crushers, over-land conveyors, pumps, mine fleet etc. The entire mining operation can thus be monitored and controlled remotely via monitors in the communications center.

In March of 2006, Siemens I&S received an order from Equinox for the engineering, design, manufacture and supply of two Mill drive systems for the ore-grinding mills. With the Simine Mill GD gearless ring-motor drive systems, the speed of the SAG (Semi Autogenous Grinding) and Ball Mills can be varied with the help of the transvector control principle. Mill operation can therefore be precisely adapted to changing characteristics of the material to be crushed such as its composition, size and hardness. The “GD” or gearless drive principle completely removes the requirement for mechanical interfacing through such components as ring and girth gears. The “impactless” design eliminates mechanical wear and tear associated with conventional systems thereby significantly reducing the amount of work and associated costs involved in maintenance and repairs to the mills. The design concepts employed in the control systems of the “GMD” ensure that the mills display superior efficiency and are more energy efficient than conventional drive systems. Further benefits derived from the GMD concept are such features as “Soft Start and Stop”, as well as “Frozen Charge Shaker”, a function which allows for the controlled detachment of the grind medium which may have become compacted in the grinding shell whilst the mill was stationary. This feature prevents expensive damage to the mill shell, removes the need for manual cleaning and thereby reduces downtime and subsequently production losses.

With the help of the “eWD” electronic documentation system, a comprehensive suite of documentation and information pertinent to the specific mill installation is generated during the commissioning phase. This ensures that all the relevant information is available online to facilitate maintenance and optimization of the mills.

Siemens is to equip the new mine with the entire “In-Pit “electrical infrastructure. All the equipment will be developed, built, installed and commissioned by Siemens. First-Line maintenance of the equipment is also included in the project scope. The mine is scheduled to begin production during the second half of 2008.