Marine Expertise in South Tyrol
That a firm from South Tyrol should be dealing with stripping paint from ships’ hulls is already odd enough. That this firm should in addition, within 18 months, have developed a completely new and unique method of paint stripping, and have immediately secured the contract to install a prototype in the Hamburg dockyard of Blohm + Voss, global leaders in ship repair, is truly remarkable. What borders on the sensational, however, is the fact that the 12,000 litres of highly toxic water used in this innovative method for marine paint-stripping can be purified within a few hours and then returned to the water cycle. The South Tyrol firm that has achieved this minor miracle is called “Renetex” and is a technology firm within the TIS innovation park.
from left to right: Marco Cristoforetti, Hans-Jürgen Schmitz and Gerhard Mayerhofer
“Mobile Container-Filtration-Facility for Stripping Paint from Ships’ Hulls” is the technical term for the technology which Renetex has developed. What makes this new cleaning process so very special is that whilst the external hull is being cleaned with high pressure water jets, the resulting effluent is collected and chemically purified. After this process, the chemically cleaned water is so pure, that it can be released into rivers or the sea without any worries.
That sounds easier than it really is“, says Renetex Director Gerhard Mayerhofer. Because cleaning a ship’s hull involves removing a layer of anti-fouling paint of at least 2 mm thickness. These anti-fouling paints will not only be covered in salt, seaweed, algae and barnacles, but are above all highly poisonous. So cleaning a ship produces a fair quantity of mucky liquid. As an average-size ship has an external surface area of around 8,000 square metres, removing a two millimetre thick layer of paint will produce around 16 tonnes of waste water. This vast quantity of poisonous effluent will then be sufficiently purified in two to four hours, so that the only particles remaining in the water will be less than one micron (thousandth of a millimetre) in size. Currently used cleaning methods involve sand-blasting the hull, resulting in an additional 75 to 100 tonnes of contaminated sand per ship, which then has to be treated as toxic waste. The cleaning method used by Renetex requires, by comparison, far fewer resources, in addition to its ecological advantages.
As the Renetex filtration facility is a mobile rig, this equipment can be used in exactly the location where it is required. The entire rig weighs around 20 tonnes and can be transported by lorry.
At the IFAT ENTSORGA 2010 exhibition, the world’s leading trade fair for water, sewage, waste and raw materials management held in Munich at the end of September, with 110,000 visitors from 185 countries, Renetex, in collaboration with Hammelmann, the world’s largest producer of high pressure pumps, presented its innovative method for cleaning ships’ hulls. A delegation from Vietnam was particularly interested in the Renetex method for marine paint stripping. In mid-October Renetex is planning an on-site inspection of a leading Vietnamese dockyard, in order to assess the size and compatibility of their rig with the Vietnamese repair facilities. They have just completed the same calculations for the first installation in a large Spanish repair yard, with an expected delivery in spring 2011.
There is no doubt in this sector that within about ten years the entire marine paint stripping industry will have changed over from the current method using dry sandblasting to high pressure water technology, as much for economic as for ecological reasons, and that an enormous market is about to open up for the Renetex Filtration Container process.
