The majority of the water used in our production process is required for cooling. After only a moderate temperature increase, this water is returned to the river in an unpolluted condition. The water used within the production process is purified in a special, biological waste water treatment plant. Parallel to the process occurring constantly in nature, a naturally developed community of aquatic organisms, (bacteria, unicellular and multicellular organisms), so-called activated sludge, is specialised in the respective food supply (= pollutants) in industrial waste water. This cleaning process occurs under optimised conditions in our own waste water treatment plant, which comprises three BIOHOCH® reactors.