The NORCURE method of desalination, or chloride extraction, is a non-destructive electrochemical treatment to halt and prevent future reinforcement corrosion in chloride contaminated concrete. The method extracts chlorides from the concrete, and simultaneously increases the pH level in the surroundings of the reinforcement steel sufficiently to durably passivate the reinforcement. Chloride extraction is performed by applying an electric field between the reinforcement steel in the concrete and an external temporary electrode mesh. The electrode mesh is sprayed-in with a mixture of potable water and cellulose fibre. During treatment, chlorides are transported out of the concrete towards the the concrete towards the positively charged external mesh by means of ionic migration. The NORCURE method has been applied to many structures, including several bridges in different parts of Europe and one in Canada. The paper presents some of these projects and the results achieved.
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