The use of cathodic protection by galvanic anode is an effective and long used method to fight against corrosion of metal structures immersed at sea (e. g. ships, docks on piles, offshore platforms…). The oxidation of these anodes, often composed of zinc or aluminium, causes the release and diffusion of metal elements in the form of ions or oxyhydroxides. With the development of ORE, the question of the effects of anode degradation has reappeared in civil society and been relayed by government departments, so it is important to be able to provide scientifically substantiated answers to this question.
To quantify the chemical compounds emitted by the galvanic anodes of ORE structures and the risk associated with their dispersion in the marine environment
- Literature review of cathodic protection and their potential impact on the environment.
- Modelling of the dispersion fluxes of metals released into the environment at different ORE sites located on French coasts
- Characterisation of the chemical risk linked to metals from galvanic anodes for aquatic species (living in the water column)
By combining ecotoxicological expertise and hydrodynamic modelling, the ANODE project has determined that there is no risk
associated with most of the elements making up galvanic anodes, namely zinc, iron, copper and cadmium. On the other hand, concerning aluminium, additional experiments are necessary to conclude. The two currently available Predicted No-Effect Concentrations (PNECs) do not seem suitable for this assessment. These thresholds must therefore be refined and include data from in situ measurements in order to be able to estimate the possible risk associated with aluminium releases.
Partners and funding
This project is led by Ifremer and France Energies Marines.
The total project budget is €311K.
This project receives funding from France Energies Marines and its members and partners, as well as French State funding managed by the National Research Agency under the Investments for the Future Programme (ANR-10-IEED-0006-30).
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