Dear chakara One more thing. You have not indicated whether this corrosion + fouling problem is a recent problem or it is present since the beginning of plant commissioning. In case it a recent development, try to find out what change was made prior to this problem. In one of NACE discussion, (Denevr, 2002), a Shell spokesman had talked about similar problem (after desalter & caustic injection, at approx 300 F) after they started blending Eocene crudes with their original crudes. They also discussed that the corrosion had nothing to do with Cl- content. What you are saying is very critical about the CL ions nothing to do with corrosion Cl ions mean will react with the fe to form iron chloride this what I understand If you have that article please send it to my email to review it. No this fouling problem happened from day one it happened every 6 month . I will provide any finding and concerns to the fourm and I hope we reach to the solution . Lima Thanks for your input . Any one had article discuss the over head coorosion control please send it to my email Alsrab2001@yahoo.com