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AbstractWhile thiocyanates are useful corrosion inhibitors in some low-to-medium temperature ranges, at temperatures of 350ºF and upwards, thiocyanates are believed to be prone to thermal decomposition and subsequent environmentally induced corrosion cracking of tubular goods, especially of high strength corrosion-resistant alloys. Stress corrosion cracking has also been postulated to be a risk as a result of hydrogen sulfide production from the decomposition of thiocyanates.In the life cycle of completion brines, a stock brine is custom-blended with a variety of additives depending on the particular application. In the field, additional components may be introduced, sometimes as contaminants. Once used, completion fluid that is returned to the surface may optionally be subjected to reclamation processes for reuse in a subsequent application. Current API recommended practices specify the testing for such components as solids, pH, and iron; however, it seems reasonable that in the future the recommended practices will also include a specification on the maximum allowable thiocyanate content.Reclamation processes to date have not focused on the removal of thiocyanates from brines. This paper discusses the laboratory development and field implementation of processes for complete removal of thiocyanates from completion brines before any attempt is made to reuse them. This process works for a wide range of brines, is quite cost-effective, and enables buy-back of used completion brines with only a reasonable additional cost for thiocyanate removal.