April 2021

40 n CONVEYORS AND MATERIALS-HANDLING April 2021 www.drivesncontrols.com World’s most powerful conveyor installation ‘pushes boundaries’ T hen world’s most powerful belt conveyor system has been commissioned at the planet’s largest open pit copper mine, in Chile. The three main conveyors transport 11,000 tonnes of crushed copper ore per hour over a distance of almost 13km at the Chuquicamata mine, which is located 3km above sea level in the Atacama desert. The century-old pit has been running out of extractable reserves above ground so has had to switch to underground operations. The new conveyor system moves the ore from underground storage bins to the surface along a 7km underground tunnel that involves two conveyors and 1km of vertical elevation. Once on the surface, the ore is fed onto an overland conveyor that transports it the final 6km to a distribution silo, and raises the ore through a further 287m. More than half of this length is carried on bridge structures. Using continuous conveying technology, the system eliminates the need for 120 large diesel trucks, saving around 130 million litres of fuel per year, and reducing annual carbon emissions from 340,000 to 100,000 tonnes. It is also claimed to be the world’s first transportation system to use premium steel cable belt technology for uphill conveyors in the tunnels. The high-efficiency conveyors are driven by 5MW AC synchronous motors with a shaft torque of about 900kNm. The motors, supplied by ABB, along with liquid-cooled MV voltage-source frequency converters, have been designed to deliver cut active and reactive power consumption without needing extra network filters. ABB worked on the project with the mining technology specialist Takraf. As well as the gearless conveyor drives (GCDs), it provided engineering design, and power supply, energy distribution and automation equipment for the conveyor system, which runs both underground and overland. A novel embedded drive concept, developed by Takraf and ABB, simplified the installation and alignment of the GCD motors, compared to previous cantilevered designs. It allowed the drive motors to be assembled and tested in a factory. If a drive fails, it can be disconnected quickly from the drive pulley. The total conveyor drive power, including feeder conveyors, What is claimed to be the most powerful belt conveyor installation in the world has entered service at a copper mine in Chile. The drive power involved adds up to 58MW, and includes 11 5MW gearless synchronous motors. The new conveyor system at the Chuquicamata mine carries copper ore from underground a distance of almost 13km to a distribution silo above ground The conveyor system at the Chuquicamata mine is driven by a series of gearless synchronous motors, each rated at 5MW. The gearless drives have fewer wearing parts than alternative systems, improving efficiency and reliability.