ThyssenKrupp Industrial Solutions has received a contract from Southern Peru Copper Corp. (SCC) to supply a primary crushing and overland conveying system at the Cuajone copper mine. The contract includes engineering, procurement and construction supervision as well as commissioning support of the complete in-pit crushing and conveying (IPCC) system to process run-of-mine copper ore. It is expected to become operational in 2016.
As part of a large in-pit crusher and conveyor project now under way by ThyssenKrupp Industrial Solutions at Southern Peru Copper’s Cuajone mine, Siemens will install the same type of gearless drive system currently in operation at the Antapaccay copper mine, shown here.
ThyssenKrupp is supplying a semi-mobile crushing plant with discharge, transfer and two overland conveyors capable of transporting 120,000 metric tons per day (mt/d) of crushed ore to an existing coarse ore stockpile. The copper ore will be fed directly into a semimobile crushing plant located in the mine. Truck ramps made of sectional steel modules provide access for mine trucks with payloads up to 360 mt. The crushing plant’s main service and operating areas, including electrical infrastructure, will be physically separated and independent from the truck dumping level, which will significantly reduce vibration, dust and noise levels. According to the company, the semimobile design is especially suitable for mine sites affected by frequent seismic activities.
Crushed ore from the new 63- x 114-in., 1,200-kW direct-drive ThyssenKrupp gyratory crusher is extracted from a surge bin beneath the crusher by a heavy-duty, low-speed belt feeder. The 2,800-mm-wide belt will run at a nominal speed of 1.5 m/s and is powered by an 800-kW conventional drive and a variable frequency drive (VFD). A 400-m-long sacrificial conveyor carries the crushed ore from the semimobile crushing plant and crusher discharge conveyor to two overland conveyors spanning the 7.5-km route to the coarse ore stockpile.
The ST 6800 belt on the first of the two overland conveyors is 1,830 mm wide and will run at 6.2 m/s. It is powered by two 6,000-kW Siemens gearless drives. The largest of their kind in the world, these conveyor drives utilize Siemens Integrated Drive System (IDS) technology to provide an expected level of availability exceeding 99% by eliminating many traditional conveyor drive components such as reducers, couplings and motor bearings, and reducing associated maintenance needs. Siemens said the applied technology not only significantly increases the capability of overland conveyors for ever-higher capacity requirements and higher speed applications, but it also leads to reduced overall energy consumption and higher efficiency.
The Gearless Drive System has been developed in cooperation by ThyssenKrupp and Siemens and was first installed in the Prosper-Haniel coal mine in Germany in 1985. More recent gearless drive conveying projects provided by ThyssenKrupp include a dual 3,800-kW gearless driven conveyor for Glencore’s Antapaccay mine in Peru, five 5,000-kW gearless drives for an overland conveyor system in Chile, and overland conveyors powered by four 4,400-kW gearless drives for MMG’s Las Bambas mine in Peru.
Christof Brewka, head of operating unit Mining at ThyssenKrupp Industrial Solutions, 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 customized solutions for the mining industry which provide added value for our customers while at the same time helping to conserve natural resources.”
Zlatan Azinovic, CEO of ThyssenKrupp Industrial Solutions (Peru), said, “As part of our global growth strategy, we are further strengthening our footprint in South America. Our service center in Peru enables us to provide better and faster services to our customers in the local mining, minerals and cement industries. Only recently we have also invested into new service centers in Brazil and Chile.”
Siemens will provide the automation system, the power distribution equipment, and the drive system for the conveyors. The IDSs with gearless drives are expected to offer a high level of availability and also enable the use of a continuous conveyor belt to eliminate the need for transfer stations and thus reduce maintenance time and costs, while enabling drive efficiency to be increased by 3%.
The conveyor belt system comprises three individual sections and a total of five IDSs. For the largest of the belt sections, Siemens is supplying two gearless 6,000-kW drive systems comprising a low-speed synchronous motor and a Sinamics SL150 cycloconverter. The two smaller feed and discharge belts will be driven by two 500-kW low-voltage motors using Sinamics S150 inverters with regenerative feedback capability and one 1,200-kW medium-voltage motor. The automation components and related components are contained in modular electrical rooms (E-houses).
Siemens also supplied a drive system for the HPGR (high-pressure grinding roll) system at Cuajone in 2013.