Steam Attemperation Corrosion

[karljp]

Has anyone experienced any corrosion problems in high pressure (40bar) steam line downstream from an attemperation unit? The corrosion occurs on the pipe top surface and looks like oxygen pitting....could it also be liquid impingement attack? No similar attack was occurring in the 6bar adjacent line also fitted with an attemperation unit fed with the same returned condensate as the 40bar line.

 

[hacksaw]

not knowing your process arrangement, you should not use returned condensate for attemperation until it has been deaerated and otherwised treated.

are you using an attemperation valve or one of the older injection styles?

how far down stream is the corrosion taking place?