Material Compatibility for Industrial Water Service

[Pavan Kumar]

Hi All,

I have been asked to check the compatibility of Lean Duplex Steel for Industrial water, spec give below. I wanted to know how I can check this. On checking this forum I found that there is Langelier index which tells you if Caco3 will precipitate or not, but then how do you check if the material is suitable for this spec.

Demin Water on carbon steel - Water treatment and distribution

I need advise how to deal with demin water (chemical additive??) so that it will not be too harse on carbon steel piping, without using stainless steel as an option?

www.eng-tips.com

Thanks and Regards,
Pavan Kumar

 

[EdStainless]

Normally with a scaling index (any of them) the water either scales or it dissolves metal.
However, with SS there is little risk of dissolving metal.
The issues in SS are pitting or crevice corrosion.
So you look at Cl (+F), pH, and temperature.
There are a number of handy sources for pitting limits for various SS alloys.
Considering that lean duplex grades are generally equal-to or slightly-better than 316L.
Though unless you are doing this for strength reasons, if this water will never scale 304L might work just fine.

 

[pierreick]

Hi,
On top of the comments from Specialist, you may want to perform indexes calculation and validate the quality of the water (corrosive) .
Underneath you will find link to support your knowledge on SS steel.

Library - SSINA

www.ssina.com

Pierre