Proposal
Chemicals in decommissioning activities are not considered as an important challenge as far as all the products used are selected from the PLONOR list. Consequently, an important work has to be done to obtain safe and efficient products to facilitate cleaning operations and to limit the volumes of polluted water. The main constraint is to propose detergent formulations that are non-toxic and biodegradable. Furthermore, formulations must be compatible with cold seawater and must allow a fast separation of hydrocarbons from the aqueous phase. The objective of this paper is to present the development of a strict methodology for cleaning products selection. The innovative aspect of this methodology is firstly based on a pre-selection of safe molecules coming from a green chemistry, such as alkylpolyglycosides for instance. In a second step, formulations based on mixtures of several efficient and safe active matters are tested on different supports (glass, steel, cement…) in order to assess their detergent efficiency against several types of crude oils and weathered crude oils, the kinetics of separation of the formed emulsion, the formation of foam and the quality of the separated aqueous phase. Ecotoxicity tests on molecules are performed according to OSPARCOM guidelines (aquatic toxicity, biodegradation, and bioaccumulation). Complementary toxicity tests are also carried out on the separated water after cleaning, in order to estimate the toxicity of the aqueous phase to be discharged. The last phase of the methodology consists in a validation of formulations performances in large scale experiments performed in CEDRE (Center of Documentation, Research and Experimentations on accidental water pollutions, France), on a specific clean-up device that simulates typical operations of cleaning under pressure. The main objective is to develop green formulations for cleaning oil polluted surfaces through a rigorous methodology based on technical and environmental criteria.
