When first installed, cooling water systems contain contaminants associated with fabrication, such as grease, dirt, debris and mill scale. Without an effective clean-up procedure the presence of dirt can lead to the early onset of corrosion, as inhibitors are unable to form protective films on a surface contaminated with grease or rust. This study investigated several proprietary cleaning and pre-filming procedures to
determine which produced protective, passive films prior to the
commissioning of new plants. The main conclusions from this study are:
• Alkaline degreasing produces the cleanest surface. • Alkaline degreasing agents should not be used if the system contains copper alloys. • Acidic cleaner is the most efficient rust remover. • The best passivation and corrosion control was given by a phosphate/polymer
treatment.