Régénération continue des bains de PEG utilisés pour la consolidation des bois archéologiques gorgés d’eau

ARC-Nucléart a élaboré un système de régénération des bains de polyéthylène glycol (PEG), utilisés dans le traitement de consolidation des bois archéologiques gorgés d’eau et progressivement pollués par différentes bactéries, par les substances dissoutes et les particules apportées par les bois eux-mêmes. La nouveauté de cette approche est le remplacement de l’usage des biocides par l’extraction et la neutralisation des contaminants et ce suivant quatre axes : le retrait des particules et des levures par micro-filtration, celui des ions par résines à lit fluidisé, la désinfection de la solution de PEG par passage devant une lampe UVc et l’aération des bains. Ces mesures permettent de régénérer les bains et donc de réduire sensiblement l’impact économique et environnemental des traitements tout en améliorant leur qualité.ARC-Nucléart has developed a system for regenerating PEG (polyethylene glycol) baths, used in the treatment for consolidating waterlogged archaeological wood progressively degraded by bacteria, by substances that have dissolved in the water and by particles added by the wood itself. The novelty of this approach lies in its method of replacing the use of biocides with a fourfold method of extraction and neutralizing contaminants: removal of particules and yeasts by micro-filtration; removal of ions by fluidized beds of resin/activated charcoal; disinfection of the PEG solution by running it past an UVC lamp and by air bullage (oxygenation) of baths. Using these measures to regenerate the baths markedly reduces the economic and environmental impact of the treatments at the same time as improving their quality

Effective biocide to prevent microbiological contamination during PEG impregnation of wet archaeological iron-wood artefacts

International audienc

Post-treatment Study of Iron/Sulfur-containing Compounds in the Wreck of Lyon Saint-Georges 4 (Second Century ACE)

International audienceA pre-restoration diagnosis revealed a high amount of pyrite in the wood of the Lyon Saint-Georges 4 shipwreck (end of the 2 nd century). The occurrence of this phase is supposed to result from the microbiologically influenced corrosion of the iron fasteners. So, all the nails and metallic elements were removed from the remains before treatment and the wreck was consolidated by polyethylene glycol impregnation coupled to a specific desalination process. Treated and non-treated samples extracted from the wreck were studied in order to identify the iron/sulfur-containing compounds present in the wood before and after treatment and figure out its effect. Sample analyses relied on an original approach combining magnetic characterization methods and more common elemental and structural analysis methods. The results showed that the treatment was effective in removing soluble salts. However, a large amount of unstable iron sulfides remained inside the wood