Protection for sea water wetted constructions
Constructions made of concrete, steel or wood in tide areas become rapidly colonized by marine organisms thus making them more corrosive and accessible for wave rubbings and destruction. In addition the constructions can become colonized from non local hard substrate preferring animals resulting in a “reefing” of the animal community. The electrochemical antifouling system presented here has the potential to avoid the described effects. It consists of a metallic direct current operated grid electrode, which surrounds the construction. The counter electrode is either a corrosion resistant ring or grid. Direct current causes electrolysis of the water and subsequently an increase of local pH values near the grid, which is in the operation mode switched as cathode.
Features and benefits
- simple and flexible modular system adaptable to the form of the construction
- can be retrofitted
- modification of the current density and polarity allows for different modes (Operation, Repair and Dismantling mode)
- low operation and service costs
- power supply from regenerative sources (photovoltaics) is possible
The insulation of the construction depends from the composition and could be made from non conductive mats or insulators. Non conductive construction allow for the direct fixation of the counter electrode. The normal operation mode causes aside of pH changes the accretion of Brucit (Mg(OH)2) onto the grid electrode. The hardness Brucit is easily washable from the structure. At lower current densities accretes the harder Aragonit (CaCO3). Both accretions can be removed through reversing the polarity.