Volkswagen closes in on wastewater-free automotive production
Volkswagen Group is looking to make its production factories "wastewater-free" and has revealed that it is close to achieving this at a number of sites.
The car maker has a goal to reduce freshwater consumption across its brand portfolio by 25% by 2018. It has since identified that virtually all of its water consumption (95%) is directly attributed to the production process, most of it upstream in the supply chain and 10% in its own factories.
Using lifecycle assessment, Volkswagen computed the proportion of water recovered and reused across 45 sites in a footprint mapping exercise. It found that combined, the sites used 3.8 million cubic metres of recycled water, corresponding to 8% of freshwater uptake.
The company's goal is to operate a closed cycle in which water is reused as often as possible. Its treatment plants employ membrane and evaporator techniques, allowing the bulk of process water to be reused. This way, more than 95% of the water remains in the cycle or is used for cooling, flushing toilets and garden irrigation.
Volkswagen has undertaken a number of initiatives across its production sites to improve water efficiency. At its Wolfsburg plant in Germany, the painting of plastics is virtually free of process water - achieved through a combination of technologies such as dehumidifying drying.
The company's Braunschweig plant in Germany has a conductance-controlled water spray metering system installed in the paint shop which saves 34,380 cubic metres of water, reducing overall costs by around £185,000.
At its Pune plant in India, more than 99% of all biodegradable materials are removed using biological wastewater treatment technologies such as a membrane bio-reactor, allowing water to be reused on-site. This ensures that almost 100% of the wastewater is returned to the cycle. The Pune plant also uses special taps which can reduce freshwater consumption by 75
Meanwhile at the LEED Platinum certified Volkswagen Chattanooga plant, which the car maker claims is the world's most sustainable automotive manufacturing facility, rain water collection provides 700,000 toilet flushes a year and cools wielding machines. Six million gallons of water are saved in the paint shop through the use of a dry scrubber tool.
Water stewardship on a wider level is also being promoted in Mexico, through the company's 'Think Blue. Nature.' programme which includes a major reforestation and youth education project in the national park of Puebla.
Here 490,000 mountain spruce trees have been planted since 2008 in cooperation with 40 partners from the component supply industry in order to stabilise the region's water table. Thanks to the improved seepage of rainwater, an additional water volume of up to four million cubic metres per year is now available.
The Volkswagen performance may counter to the overarching trend. Earlier this year edie reported that an independent report on car manufacturing as a whole had actually seen water consumption increase.