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Extinguishments of large scale solvent res produce large amounts of water that may contain various uorinated surfactants depending on the type of re ghting foam used. Due to their chemical nature, uorinated parts of uorinated compounds are highly resistant to biochemical and advanced oxidation processes. Therefore the current treatment for the degradation of uorinated surfactant from water used in re extinguishment is high temperature incineration of the water in halogen resistant incinerators. This paper aims to propose a process for purifying re ghting water containing uorinated surfactants.Pilot re ghting waters resulting from heptane re extinguishment with reghting foam containing a uorinated surfactant were produced. Suspended matter was estimated on the basis of turbidity measurement and uorinated not suitable for direct membrane processes because of high fouling, hence electrocoagulation and ltration were required. Electrocoagulation with aluminium electrodes at a charge loading of 600 C L −1 followed by ltration were found su cient to remove turbidity from pilot re ghting waters. Fluorinated surfactant removal was 71 77% and was not signi cantly increased by higher charge loading. Floc separation in bulk solution was achieved by ltration. Reverse osmosis of pretreated pilot re ghting water and concentrated model solutions of pretreated re ghting water were studied and though ux decline was observed, measured retention rates were 99.94 99.97%, with permeate concentrations down to 10 16 µg L −1 of uorinated surfactant at the laboratory scale. The concentrate from reverse osmosis could be recycled in electrocoagulation-ltration. Experimental results indicated that electrocoagulation and ltration followed by reverse osmosis e ciently treated the water from re extinguishment, which enables a further scale-up work.

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