Correa regenerativa thyssenkrupp

MATERIAL HANDLING IN MINING – LOS PELAMBRES By: Christof Brewka

When by the end of 1999 the Los Pelambres overland conveyor system starts its operation, a new benchmark in belt conveyor technology will be set. This presentation gives an introduction into the design of this record breaking conveyor system and will elaborate on some of its innovative features.

Introduction The Los Pelambrescopper mine is located approximately 200 km north of Santiago, Chile, high in the Andean mountains next to the border to Argentina. When the owner decided to proceed with a major expansion, it became necessary to find an efficient way to transport the coarse ore from the mine to the new concentrator facility at a rate of 8,700 metric tons per hour, over a distance of some 13 kilometers and droppingover 1300 meters in elevation. To handle this task, a belt conveyor system consisting of three individual conveyors has been selected. To protect the conveyor from the rock slides and avalanches prevalent in this area, most of the conveyor runs inside tunnels which have been driven through the mountain side.

Conveyor Layout

In July of 1997, a contract was awarded to Krupp Canada to designand supply the entire coarse ore conveyor system. At the time of this presentation, the installation of the conveyor system is nearing completion. The commissioning of the system is expected to take place in the last quarter of 1999. Conveyor Layout Copper ore is transported by large mine haul trucks to the primary crushing plant located at the outside perimeter of the mine. A gyratory crusherreduces the run-of-mine material to belt-conveyor acceptable particle sizes of 300 mm and less. The crushed material is collected in a surge bin underneath the crusher, then reclaimed by the crusher discharge conveyor and stacked onto the

Crusher Discharge Conveyor and Mine Stockpile

Material Handling in Mining – A Case Study

Technical Seminar 1999

mine ore stockpile. With a belt width of3,000 mm at a belt speed of 3 meters per second, the crusher discharge conveyor is designed to convey 14,000 tons per hour. The material is reclaimed from the mine stockpile by four belt feeders and loaded onto the first of the three coarse ore overland conveyors. At the end of the coarse ore conveyor system, the copper ore is discharged onto the concentrator stockpile. The discharge end of thelast coarse ore overland conveyor can shuttle back and forth over a distance of 62 meters, stacking the material onto the longitudinal stockpile.

Head End Conveyor Cv-007 with Concentrator Stockpile location

The overall conveying distance of 12.7 kilometers is divided into three individual conveyors of 6.0 km (CV-005), 5.3 km (CV-006), and 1.4 km (CV-007) lengths. The conveyors follow adownhill slope of approximately 10 % with a short 25% slope at the end of the tunnel at conveyor CV-007. Drive System Due to their similar length and vertical drop, conveyors CV-005 and CV-006 are largely identical with regard to their drive configuration. Both conveyors are equipped each with four 2,500 kW drives. Conveyor CV-007 is equipped with two 2,500 kW drives, bringing the total installed drivepower to 25 MW. The conveyor system will operate in motoric mode at low capacities, and will change to generative operation at a belt loading of 20% or more. In this condition, the drives will feed electrical energy back into the power grid. The electric motors are regulated by adjustable frequency drives (AFD). When started, the conveyors are accelerated in 40 seconds following a S-shaped speedcurve. Stopping is performed in Drive Station Conveyor CV-005 sequence based on predetermined stopping ramps ranging in length from 76 to 80 seconds. Operational parameters, such as belt speed, belt tension, belt loading, motor torque, etc. are continuously monitored and processed by the drive control system to adjust the speed and to detect any possible failure. Since loss of control can lead...