Adsorption processes for an improvement of the quality of sea water in aquaculture
Résumé
In shellfish hatcheries, as in the open sea, adequate water quality is essential for the different life stages of the oyster Crassostrea gigas, from fertilization to spat fixation. However, despite the treatments implemented upstream of the various establishments in the area of Bouin, France (fine filtration and disinfection by ultra-violet radiation), the failure to reach the D larval stage in the oyster hatcheries has been regularly observed sometimes simultaneously in several establishments. This reflects a punctual deterioration of the water quality. This context motivated the ADAQUA project submitted to SMIDAP supports. This project aimed at studying the process of adsorption on granular activated carbon (GAC) for an improvement of seawater quality in shellfish hatcheries, positioned upstream of the farms in order to protect them from any chemical contamination.Following the identification of the main pesticides present in the waterways of the study area, three molecules, simazine, metolachlor and glyphosate were selected as the model organic pollutants for the determination of adsorption performances on commercial activated carbon. A first part of the study was conducted at laboratory scale, at IMT Atlantique, to determine the adsorption capacities of these molecules on different adsorbents. The results showed the retention performance of molecules such as simazine and metolachlor on the activated carbon selected for the study. The project aimed also to highlight the retention capacity of glyphosate. An analytical method has been developed specifically to measure this molecule. Glyphosate is difficult to retain on conventional carbonaceous adsorbents. It was therefore considered to test other adsorbents. The choice was oriented towards commercially available adsorbents, sufficiently resistant from a mechanical point of view and not presenting a priori disadvantages relative to shellfish farming activities.
Domaines
| Origine | Fichiers produits par l'(les) auteur(s) |
|---|---|
| Licence |