Griesser AG: World premiere - Openair plasma in coil coating
The plasma installation which is only 2 m wide replaces a 21 m long cleaning line and hence tons of chemicals.
Griesser AG, Switzerland, is one of the leading suppliers and manufacturers of sunshade systems in Europe. The aluminium coils required for the production of slatted blinds and shutters are coated in-house by applying a coil coating method. In 2007, Griesser was the world's first company to implement an environmentally friendly way of pretreating aluminium coils through the use of Openair® plasma.
At Griesser, the plasma technique completely replaces the environmentally polluting wet-chemical processes in the cleaning operations which are conventionally employed by the aluminium industry. The results of pretreatment exhibit a striking improvement in hydrophilic properties in comparison with the wet chemical process. In the latter case the wetting contact angle is about 48 – 52°, while after treatment with Openair plasma it is only about 18 – 28°.
At Griesser, the computer-controlled installation, which measures only 2m x 1.50m, replaces today a 60m long cleaning line. Depending on the degree of soiling of the coils in the Griesser factory, large volumes of chemicals and thousands of tons of effluent can be avoided. Also, because no waste is produced in the precleaning process, the otherwise customary neutralisation in the form of wastewater treatment is unnecessary which, in the piece coating plant alone, makes a difference of 20 tons of filter cake (requiring special disposal) per year. Employees also value the environmentally friendly working conditions, where before, using wet-chemical pretreatment often meant noxious vapors and high temperatures in the workshop. Thanks to the use of the Openair® process, the speed of the coil coating installation is now four times the former speed. Adding to this is the doubling of the production volume.
For the new environmentally friendly process in the surface pretreatment of aluminium coils, Plasmatreat was honored in the USA with the FTM INNOVATION AWARD 2007. One year later, Plasmatreat and Griesser were jointly nominated for the European Aluminium Award 2008.
Openair® plasma offers the user the following values:
- Complete elimination of wet chemicals from the cleaning process
- Avoidance of thousands of tons of effluent per year
- No neutralization of wastewater, no disposal costs
- No heat or vapor generation at the workplace
- Quadruplication of the production speed
- High reliability and effectiveness of the cleaning process
- Striking improvement in hydrophilic properties
- Doubling of the production volume
- Saving of production steps
- Saving of labor
- Reduction of the operating costs