Up to 30% less energy consumption in the painting process with the EcoDryScrubber from Dürr

Dürr presents a world first 

Up to 30% less energy consumption in the painting process with the EcoDryScrubber from Dürr 

• First-ever system for regenerative dry overspray separation in automobile production 

• Energy savings through reduced air treatment 

• Considerable cost per unit and environmental benefits

A new technology developed by Dürr enables energy savings of up to 30% in automobile painting, which is by far the most energy-intensive manufacturing process in the production of vehicles. This figure refers to the whole paint shop. If we consider the spray booths only, the percentage of energy saved is 60%. The EcoDryScrubber system presented on October 15 works with recirculation of the booth process air and dry separation of the surplus paint particles during paint application. Recirculation reduces the energy required for air treatment significantly compared to conventional spray booths. Moreover, the elimination of standard wet separation means that fresh water is no longer required for paint separation. This results in considerable improvements in energy consumption and in CO2 and paint-particle emissions.

More than 150 representatives from all the major automobile manufacturers seized on the opportunity to take a closer look at this innovation at first hand at the new Technology Center at Dürr’s future central location in Bietigheim. Besides guests from Germany and other European countries, Dürr was even able to welcome visitors from South and North America and Asia.

Ralf Dieter, Dürr AG’s CEO, commented: “As technology leader, Dürr already addressed the issue of energy and CO2 optimization early on. So, today, we are in a position to offer our customers equipment and systems with which energy and unit costs can be significantly reduced. Our dry separation system clearly underscores the results of our development efforts.”

Depending on the level of automation between 20% (manual painting) and 85% (automated exterior painting) of the material reaches the body when applying wet paints. In the conventional process the rest of the paint, known as “overspray“, is carried with the downward flow of process air into the lower section of the spray booth where it is bonded in water with the aid of specially designed venturi tubes. The process air is drawn off as, through the contact with water, it absorbs too much moisture for it to be re-used, and it also contains paint-particle residues. As a result, a fresh supply of air has to be treated and fed to the booth, which consumes a lot of energy.

By contrast, spray booths equipped with the EcoDryScrubber require far less fresh air. The reason: the process air does not pick up added moisture and the paint particles are removed in a dry filtration system beneath the booth, so it can be re-used. This recirculation of the process air reduces energy costs for air treatment in the spray booth by about 60%. In addition, the water required for humidifying the air is reduced by about 80% since less air needs to be conditioned. There are further savings of roughly 5% in maintenance costs; this is due not only to the fact that the system is fully automated but also above all to the long filter replacement cycle of over 15,000 hours’ operation. Finally, the compact construction reduces the cross section of the booth by about 35%, to which another Dürr innovation, namely the use of space-saving EcoRP painting robots that travel along rails fitted to the walls of the booth, makes an important contribution.

Reductions in cost per unit and lower CO2 emissions 

The air-conditioning for the booths is the most energy-intensive part of the vehicle painting process. The energy optimizations achieved with the EcoDryScrubber therefore have a major impact on a paint system’s total energy consumption. In a paint shop with an annual capacity of 158,000 car bodies use of the EcoDryScrubber lowers energy consumption by 16 million kWh a year. This is equivalent to a reduction of 5,200 tonnes in CO2 emissions. Over a car model’s total product life cycle of seven years Dürr’s innovative solution can produce savings in the region of € 8 million. Over the same period CO2 emissions are reduced by 36,400 tonnes.