NEW YELLOW METAL CORROSION INHIBITOR WITH BETTER PERFORMANCE, IMPROVED STABILITY, AND LOWER TOXICITY

摘要

Yellow metallurgy (copper and its alloys including admiralty brass) has been widely used in heat exchangers due to its high thermal conductivity, antimicrobial properties etc. However, these metals suffer from corrosion in acidic-to-neutral and highly halogenated environments that are common in cooling water systems. This may result in failure of heat exchangers and consequently loss of production and costly replacement. In the last few decades, different triazole chemistries were used as a protective filming inhibitor for yellow metal. These chemistries have their limitations, including poor stability in halogenated environment, high consumption rate, and high aquatic toxicity. To overcome these challenges, Nalco Water has developed an innovative yellow metal corrosion inhibitor with improved halogen stability, lower consumption rates, and reduced aquatic toxicity compared to triazole compounds. The new patent-pending non-triazole based chemistry has been evaluated for its performance in electrochemical tests, pilot cooling tower tests and customer field trials. The results from both lab and field trial will be discussed in detail. Additionally, a handheld analyzer has been developed and evaluated to precisely measure this low toxicity yellow metal corrosion inhibitor.