BMW says no to waste water

The BMW Group has announced a waste-water treatment and re-use process at its engine plant in Steyr, Austria, that is so effective the mains drainage could be disconnected.

Using a new combination of various membrane technologies, all manufacturing waste water in the plant is treated and fed back into the production system. The mains drainage connection for operating waste water from the production area was closed at the end of 2006, which means that around 30 million litres of water will be saved each year.

Water is used in engine production to create an emulsion with coolants for milling and turning, and for washing or rinsing during the finishing of cylinder heads, crank cases, crank shafts and connecting rods. A waste water treatment system using nanofiltration technology was introduced at Steyr in 2003.

‘This system produced such convincing results that we decided on the ambitious objective of further improving our waste water treatment so that in the future we would be able to introduce a completely enclosed water cycle for production’, said Franz Hornbachner, who is responsible for planning fluid technology.