Biofouling in coastal monitoring infrastructure
Underwater instruments aimed for measuring, observing and monitoring in the marine environment face a major problem, biofouling. This is mainly because biofouling may result in a rapid decline in instrument performance, deterioration of data quality and the requirement for frequent and costly maintenance of equipment. Addressing this problem, the BRIMOM project developed a wide range of biofouling reduction technologies for application to underwater instruments with special emphasis on optical and membrane sensors. Such technologies include local electrochemical generation of chlorine, hydrogel coatings containing a specific surfactant and Ultra Violet C (UV-C) illumination. The biofouling process depends on different factors including the season, the location such as arctic, temperate and tropic as well as the water type like estuary, coast, open and ocean. All these factors make the selection of the most appropriate antifouling strategy for a specific type of equipment a very difficult task. In the case of automated monitoring stations antifouling techniques based on flow through systems were developed and tested for two water types, the river Elbe and the North Sea. Extensive testing allowed for the identification of optimal antifouling techniques with minimal energy and reagent consumption in relation to the location of the station and the season. It was shown that under different flow rates a wide range of cleaning procedures may be used depending on the area. These procedures vary from automated tap water rinsing for artic waters over acidification to pH 3 for temperate waters up to a combination of acidification and chlorination for tropical waters. Using a reagent free antifouling method that can be easily installed and safely maintained could greatly reduce biofouling for several months offering a satisfactory data quality. For further information click at: http://www.brimom.org(odnośnik otworzy się w nowym oknie)