The element of life
At Airbus, processed water supports a wide variety of activities, from fire fighting and plant cultivation to its use in many of the company’s hangars and workshops – which is why the company puts an emphasis on recycling and reusing this important element.
In new buildings at Airbus’ Hamburg, Germany site, additional piping for processed water was laid during the construction phase. These extra pipes were installed in some of the facility’s older hangars, and in due course all the buildings will be equipped in the same way. On average, individuals need 127 litres of water a day, and nine-to-14 litres of this amount goes down the drain with each toilet flush. If each of the 17,000-plus people who work at Airbus in Hamburg uses the toilet at least once a day, it is a substantial loss of water.
Making good use of processed water
To reach the facility's toilets, water from the nearby Elbe River first enters a dike and then flows about 500 metres through a pressure pipeline to Hangar Three. It then enters storage and sedimentation basins, where the coarsest dirt particles are precipitated. The resulting raw water is then forced through various filters and subsequently passes into the hangar basement’s ultrafiltration plant. There, large filter modules – each fitted with 10,000 capillary tubes – catch everything over 0.1 micrometres in size. What comes out is processed water, which is then fed into the company's mains system.
At the Hamburg washing facility for cars and heavy goods vehicles (HGVs), process water keeps Airbus vehicles looking spick and span. Oil residues, traces of fuel, dirt and detergent are typically left behind by the 30 cars and five HGVs and buses that are washed each day. The dirty water is cleaned with the aid of bacteria in a fully biological wastewater treatment plant, and then returns to the circuit’s start to wash more vehicles.
Enacting safer procedures
Such environmental awareness also can be found at Airbus’ headquarters in Toulouse, France, where the replacement of cooling systems has enabled water conservation while further protecting employees’ health.
There are 20 cooling towers in Toulouse, which include both single- and dual-systems. Initially, when a conventional open cooling tower was operating, the cooling or process water would flow directly across its heat transfer surfaces. As air flows into the tower, up to 70 per cent would evaporate and cool the remaining water, which is then fed back into the system.
The potential creation of dangerous bacteria in the hot, humid cooling towers prompted Airbus to switch from conventional cooling units to so-called adiabatic cooling systems such as the Trillium-series dry cooler, which is equipped with special air evaporation pre-coolers. Their introduction has significantly reduced water consumption from 20 and 80 per cent, depending on the type and application – while making threats like biocides and algaecides, along with anti-lime agents a thing of the past.