SA mines benefit from sophisticated cooling methods

3rd April 2015 By: Bruce Montiea - Creamer Media Reporter

SA mines benefit from sophisticated cooling methods

COOLING TOWER Mines require sophisticated cooling methods and equipment to reduce temperatures to safe levels for workers

Major mining companies, such as platinum producer Anglo American Platinum (Amplats) and gold miner AngloGold Ashanti, are benefiting from ventilation and cooling technology provided by cooling tower manufacturer Tektower, a subsidiary of industrial cooling tower systems company Industrial Water Cooling (IWC).

“Today, gold and platinum mines descend as far as 5 km below surface. In this extreme environment, virgin rock temperatures often exceed 60 °C, and we are able to provide the required cooling systems,” says Tektower operations and engineering manager Stuart Loftus.

He states that deep-level mines require sophisticated cooling methods and equipment to reduce temperatures to safe levels in which mineworkers can work, which is what Tektower has been providing for Amplats’ Amandelbult platinum mine, in Limpopo, since 2009 and AngloGold Ashanti’s Mponeng mine, in Gauteng, since 2013.

He notes that the Mponeng mine, with average depths of between
2.8 km and 3.4 km, is one of the world’s deepest gold mines.

Tektower manufactured and installed a 15.1 MV, six-cell ammonia evaporative condenser at the mine’s refrigeration plant.

Loftus tells Mining Weekly that, owing to the extreme conditions underground, the mining operations use some of the largest ventilation and cooling systems in the world. The systems incorporate more than one type of cooling technology, such as evaporative condensers, mechanical refrigeration plants, precooling towers and bulk air coolers.

“These cooling systems typically work by sending ice or chilled water down into the mine to reduce the ambient mine temperature. The systems are installed either on the surface, underground, or both, depending on the depth of the mine.”

He adds that, as a mine gets deeper, the challenge of cooling the environment increases.

“For instance, in very deep or hot mines where temperatures exceed 50 °C, ice or chilled water coming from the surface would not reduce the ambient temperature to a safe level, which means that a further cooling system would have to be installed underground to rechill the water or ice coming from the surface,” he says.