The new system will be installed at the Cuajone copper mine in Peru, which has been in operation since 1976, to transport ore from the open-pit mine to the concentrator. It will replace the existing long railway haulage system and is expected to start operating in 2016.
The contract includes engineering, procurement and construction supervision as well as commissioning support of the complete in-pit crushing and conveying system to process run-of-mine copper ore.
Christof Brewka, head of mining for the ThyssenKrupp Group unit, said: “The new crushing and conveying system will significantly reduce operating costs and energy consumption as well as emissions. This makes it a good example for our leading customised solutions for the mining industry which provide added value for our customers while at the same time helping to conserve natural resources.”
As part of the new order, ThyssenKrupp is supplying a semi-mobile crushing plant with discharge, transfer and two overland conveyors with a capacity of 120,000t/d of crushed ore transported to the existing coarse ore stockpile. The copper ore will be fed directly into a semi-mobile crushing plant located in the mine. Truck ramps made of sectional steel modules provide access for mine trucks with payload up to 360t. The crushing plant’s main service and operating areas, including electrical infrastructure, will be physically separated and independent from the truck dumping level, which should significantly reduce vibration, dust and noise levels. The company stated that the semi-mobile design is especially suitable for mine sites affected by frequent seismic activities.
The 63–114in (1.6-2.9m) heavy duty ThyssenKrupp gyratory crusher with its 1,200kW direct drive takes the feed material from the feed hopper and reduces the run-of-mine copper ore to the required product size. The crushed ore is extracted from the surge bin underneath the crusher by means of a heavy duty low speed belt feeder. The 2,800mm wide ST 1800 conveyor will run at a nominal speed of 1.5m/s and is powered by one 800kW conventional drive and a variable-frequency drive (VFD). A 400m long sacrificial conveyor carries the crushed ore from the semi-mobile crushing plant and crusher discharge conveyor to two overland conveyors spanning the 7.5km distance to the coarse ore stockpile.
The first of the two overland conveyors will be 1,830mm wide with ST 6800 belting and will run at 6.2m/s. It is powered by two 6,000kW Siemens gearless drives. Among the largest of their kind in the world, these conveyor drives utilise Siemens Integrated Drive System technology to provide a high level of availability (exceeding 99%) by eliminating many of the traditional conveyor drive components such as reducers, couplings, and motor bearings and their associated maintenance times and costs. The applied technology is designed to not only significantly increases the capability of overland conveyors for ever-higher capacity requirements and higher speed applications, but can also lead to reduced overall energy consumption and higher efficiency of these conveying systems.
