Biofouling on offshore installations – an impact and monitoring assessment

Abstract

From the Abstract: “ONGC – a state owned company is engaged in exploitation of natural hydrocarbons from the east and the west coast of India, both near and far shore, from deep and shallow waters using both fixed and floating structures. The occurrence of marine fouling on fixed offshore structures has attracted interest because of its potential adverse effects on structural loading and corrosion. The biofouling is a complex biological process, their growth and attachment on offshore platforms is a universal phenomenon. The major biological growth of foulers do not differ much in tropical and other waters. An average growth of 5–10 cms. Increases the structural load by about 5.5 to 11.5% necessitating the periodical mechanical removal, which appears to be the solution so far, for fixed offshore structures. This process is costs intensive and is a structural weakening process.

Almost all the known preventative methods envisage use of toxicants…A new concept based on continuous release of toxicants, ensuring long time protection has been attempted. Two sets of test panels of standard dimensions of commonly used metals in offshore structures (ASTM-A-36 and API-2H) were installed at test platform for two different time intervals. The deposition on control panels and members of structures found to be moderate yet quite significant. The slow release of copper ion was found to have considerably reduced the attachment and growth of biofoulers.”