Guard KG, based in Wiesbaden, specializes in graffiti removal and recently cleaned approximately 1,400 square meters of sandstone masonry in the south tower of Cologne Cathedral with the help of ZUWA pumps. The heavily contaminated wastewater was removed using ZUWA's flat suction systems. Guard KG uses the KOMPAKT and ELEPHANT models for this purpose. ZUWA impeller pumps are the right choice for this type of application – residues from the porous sandstone masonry and coarse contaminants are no problem for the dry self-priming pumps.
Unlike flat suction submersible pumps, ZUWA flat suction sets always use suction mats, which can suck up liquids down to the smallest, easily wipeable residues, even on slightly uneven surfaces. This is achieved by distributing the suction pressure over the entire surface of the flat suction mats.
The Kölner Stadt-Anzeiger newspaper wrote about the clean-up campaign:
"According to Graffiti-Guard, the specialist cleaning company from Wiesbaden commissioned to clean the cathedral, it currently holds a European record for the largest graffiti removal in terms of height and area: around 1,400 square meters of sandstone masonry in the south tower at a height of zero to 100 meters were cleaned. Two-thirds of the total area was covered with graffiti of all kinds, some in several layers. On the visitor platform at a height of 100 meters, 100 percent of the natural stone surfaces were covered. In addition, a huge amount of old chewing gum was removed during the cleaning of the floor and walls. There were around 3,000 pieces on the 75-meter level alone."