Chilled water reduction on an underground bulk air cooler system by applying engineering principles

The mining industry in South Africa is seriously looking for means to reduce its energy consumption due to the rising cost of electricity supplied by ESKOM. Due to the depth of the mines large volumes of chilled water are required at the work areas to ensure the working conditions are acceptable. This places a significant load on the pump and fridge plants available. This paper investigates ways to reduce the volume of chilled water required by improving the efficiency of cooling units and by re-using the outlet water of these units. Measurements on site confirmed that these units are not used cost effectively and that significant savings are possible. It is also shown that these savings can be achieved with minor changes to the existing infrastructure.