Bechtel, developing Peru’s Antapaccay copper mine for Xstrata Copper, has used a Liebherr 630 EC-H 40 tower crane to construct the mine’s flotation cell tanks and will keep the crane operational on-site for maintenance for the next 20 years. This is the biggest model in the company’s high-top EC-H range. Liebherr Chile SA supplied the German-built crane direct to contractor Bechtel Chile, who is developing the $1.47 billion mine for Xstrata Copper. Antapaccay’s open-pit mine and processing facilities are located 4,100 m above sea level in the Yauri district of Espinar Province in southern Peru’s Cusco Region. It will initially produce an average of 160,000 t/y of copper in concentrate, plus gold and silver by-product credits. Ore will be processed in a new 70,000 t/d concentrator facility and concentrate to be transported to Matarani Port for shipment to customers worldwide.
Xstrata Copper’s agreement with Bechtel is an EPCM contract for a series of potential copper mines, concentrators and related mineral processing facilities. This includes designing a replicable copper concentrator and other facilities that can be applied to Xstrata Copper’s other projects, and which is aimed at enabling early ordering of long lead time items and reducing the engineering time and costs on individual projects.
Antapaccay is the first of Xstrata’s copper mines to use this newly designed concentrator plant, which is divided into adjustable modules with a primary crusher, grinding area, flotation area, concentrate and tailings area, and a regrind and filter plant.
The truck shop, warehouses and offices are also in this immediate area of the mine.
“Liebherr was asked to supply a crane that could handle heavy lifts and which would have a maximum reach of 80 m,” says Henning Kohler, Regional Manager for Liebherr Chile. He added that for this project, the crane featured a height of 40 m, “it was the loads that Bechtel required not the height. The 630 EC-H40 can lift 40 t maximum and 5.4 t at 80 m, and consequently was suitable for all Bechtel’s lifting purposes on the flotation cell line. Another important requirement was robustness and longevity, as the crane will have a working life of more than 20 years, in a remote location and at a high altitude. We worked closely with Bechtel, and the crane was installed on site in August 2010. The tanks were completed in November 2012.”
The new design of the flotation cells requires high precision lifting and placing during a tight construction schedule, with a wide radius to cover and a diverse range of lifting loads.
The crane has to work as an integral part of the flotation cell process, and to remain there for the life of the mine – a tough requirement for a tower crane, confirmed a spokesman at the mine, adding “There is every confidence that this is the unit that we need.”
Liebherr’s distributor for Peru, Metal Tecnica, installed the crane and will also undertake the maintenance under LBC supervision.
“The crane will be undergoing a dramatic range of temperature changes,” says Managing Director Jose Midzuaray. “Night time regularly sees temperatures of 10o or more below freezing, and during the day the temperature can be a mix of freezing point yet very hot from the direct sunlight.
“We also have to contend with low atmospheric pressure, and so maintenance of the hydraulics, electronics and mechanical system will require continual attention. However, Liebherr has a long track record of working under these kind of conditions, and we see no problems of an unusual nature occurring.”