Green Paintshop, a Contribution to More Energy Efficiency and Resource Saving in Automobile Painting

Efficiency and sustainability, these are the great trends of our time. And rightly so. Natural resources are restricted and rapidly increasing energy demand, in particular in the growth markets of the newly industrialized countries, pose great challenges for national economies. In recent times, vehicles have been rated according to their CO2 output rather than their fuel consumption. In order to lower this, new drive concepts are developed that go as far as electro mobility. In vehicle manufacturing as well, solutions are in demand that lower energy consumption and thus the CO2 emissions and handle available resources carefully. With its Green Paintshop concept, Dürr provides an integrated solution package for maximum energy and resource efficiency in automobile painting.

Every painting process begins with the pretreatment and the following dip-coating. Here the rotation procedure has prevailed. For different requirements on system capacity and flexibility, in total three systems are available in the RoDip family. With the RoDip technology, especially space-saving layouts can be realized. The missing inlet and outlet slopes, however, do not only shorten the installation length, but also reduce the tank volumes. This is combined with lower material and energy costs, the latter are about thirty-five percent lower compared with the conventional shuttle.

State of the art is a supply and exhaust air operation in the spraying booths. A majority of the energy that is used in a paintshop is needed for the necessary air preparation, indeed just less than sixty percent. Recirculation of the booth air would save a considerable part of this energy. A clearly improved efficiency of the overspray scrubbing as compared with the wet scrubber and no humidity increase as it occurs during the wet washout is a pre-condition for that. Here, Dürr breaks new ground with the EcoDryScrubber. EcoDryScrubber is based on the principle of dry scrubbing with the aid of limestone powder as a binding agent for the paint particles. The saturated limestone powder is automatically replaced by fresh powder depending on the degree of saturation and can be used in other processes of manufacture in an untreated state. In other words: with this new technology there are no paint sludge accumulations that have to be disposed of as hazardous waste, no waste water is to be treated, no chemicals are necessary for coagulation.  If one considers the energy balance of the entire paintshop, thirty percent of the total energy can be saved by the use of dry scrubbing, related to the painting booth the saving is sixty percent.

The advantages only briefly outlined here, already convinced many customers worldwide.  Since the introduction of this technology, Dürr has already received orders for thirty (30) lines.

Also, the actual paint application offers numerous possibilities to more efficiency and resource saving, especially important if one considers the great portion of the costs of materials at the total costs of the vehicle painting. For instance, with innovative color change systems, the color change losses can be reduced to an absolute minimum. A further innovation in the field of application technology is the new EcoBell3. With this rotating atomizer it was possible for the first time to design the exterior charge so compact that the interior painting of vehicles is possible with it.

Where can even larger energy volumes be saved in a paintshop? With the dryer technology and the corresponding exhaust cleaning. The compact design of the dryer with an asymmetrically designed stop zone, integrated air management and heat recovery in connection with the new, optimized TARCOM V burner technology by Dürr result in another fifteen percent. The TARCOM V burner, and this fundamentally applies to all systems, is designed so that existing installations can be retrofitted.

It is not sufficient to develop power-saving and environmentally safe technology; it must also be operated correctly. For this, Dürr expanded their process control system EcoEMOS by an interesting component - the software module EcoEMOS Energy. This tool facilitates the systematic recording and evaluation of consumption values. For instance, individual consumption places can be optimized, superfluous ones be identified and eliminated. In combination with the working time model saved in EcoEMOS, a systematic and automated reduction of consumers in production-free times can easily be realized.

With new painting installations, so-called greenfield projects, a conclusive concept saving energy and resources is certainly easier to realize.  Especially old installations, however, also offer very great optimization potentials when looking more closely. For this, Dürr offer an assessment that is carried out by designated experts with a long-standing experience and extensive process know-how.

A paintshop is an energy-intensive production area. With the Green Paintshop, Dürr offer a concept that enables an efficient and environmentally friendly operation of the installation. As a positive “side effect", considerable costs can be saved, a two-digit million amount, calculated over the model cycle time of seven years in a paintshop with a hundred and fifty thousand units per annum. Therefore, there is no reason to hesitate with the conversion.