Summary for stainless steel corrosion in ozone Discussion
stainless steel corrosion in ozone contact basin is discussed as a possible oxidation problem rather than a simple grade mismatch. Chris Lyles asked why confirmed 316 stainless steel piping in an ozone disinfection system showed loose particles and dark shadowy areas, with analysis showing oxygen, iron, and chromium. Todd Osmolski replied that ozone is a highly oxidizing molecule and that some oxidation can be expected on surfaces that are not properly surface finished, passivated, or electropolished. The thread does not give a definitive root cause or repair, but it suggests that surface condition and post-fabrication treatment are important factors in resisting ozone-related attack. In a later follow-up, David Jacques reported a similar water-treatment installation with pinhole leaks after about two years and asked whether the cause had been identified, indicating the issue can be persistent in service.
Q. I have been posed with the question of how corrosion can occur on the interior of 316 SS (chemical analysis confirmed the grade is 316 SS) piping used in an ozone contact disinfection system for a water treatment facility. I’ve been told that in some instances the ozone may cause slight corrosion, especially if the ozone is left in the pipe for an extended amount of time, e.g., when operation is shut down for the evening. The corrosion consisted of loose particles and dark, shadowy areas. The primary chemical components consisted of oxygen, iron, and chromium. Could anyone shed some light on why there is a small degree of corrosion occurring in this SS?
Chris Lyles
– Cottage Grove, Minnesota
2003
A. Ozone is a molecule composed of 5 oxygen atoms. You can expect some oxidation on surfaces that are not properly surface finished and or passivated/ electropolished.
Todd Osmolski
– Charlotte, North Carolina, USA
2003
Q. Chris,
I came across your question regarding corrosion in the ozone piping. I’m having a similar problem at a water treatment facility that has been online for approximately 2 years. It some locations the piping has developed pinhole leaks. Did you find out any further on the cause?
David Jacques
– Waterford, Connecticut, USA
2007