Newsletter December 2015

Double is better

SPANGLER – the Plus of Safety.

The mining of metal ores is a cleaning-intensive process. Take, for example, the large, open-pit Cerro Verde mine near the Peruvian city of Arequipa. The copper mine, first worked in the mid-19th century, is being modernised and expanded. As from next year, around 270,000 tonnes of copper ore and 6,500 tonnes of molybdenum will be mined there annually.

Based on UL regulations

Investment in the site includes, among other things, several pumping stations (installed in 2013) and a powerful wastewater treatment plant, which receives wastewater from the entire mine area as well as the wastewater from the ore-washing plant. SPANGLER Automation has configured the controls for the entire system and designed them according to US regulations UL 508 A and UL 698 A. This also includes the construction of the three requisite control cabinets – two in sheet steel and one in stainless steel. The stainless steel cabinet has a double external wall to reduce heat input under subtropical climate conditions.

SPANGLER employees programmed two Allen-Bradley ControlLogics control systems specifically for this plant. Due to the high safety requirements in mining, the controls are both connected redundantly. If one fails, the second is switched to without interruption, as smooth operation must always be ensured. The system controls five filter step screens, two conveyor screws and two wash presses for mechanical wastewater treatment at the highest level.

The tight safety measures in mining have shaped the whole nine-month project. Just in terms of on-site commissioning activities, a three-day safety check had to be completed in advance.

More information about SPANGLER’s production of UL control cabinets can be found here:

UL standard

Wastewater flow at Cerro Verde open pit mine
New wastewater treatment plant