What grade of SS against HCO3

[Ruudvis]

I am looking for an installation to separate CO2 from water. Because there will be HCO3 in the water, the separator will have to be made from Stainless Steel.
BUt.. What type of SS?
Would SS304 be sufficient, or do I have to use SS316?
Thanks in advance

 

[unclesyd]

Our original CO2 recovery, from the amine system, system from a Girbotol unit on H2 plant was CS with 304 SS internals. When we increased the capacity we went with an all 304/304L until the CS storage tanks. All the compressor accessories were 304 SS.

 

[Ruudvis]

Thanks for your reply, unclesyd.
You never had any corrosion problems with that system?
Were you able to look for possible corrosion of the components when you increased capacity?

 

[EdStainless]

Carbonic acid is weak. 304 will be good enough as long as there are no chlorides in the water.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

 

[Ruudvis]

And what if there is 160 mg CL/l?

 

[unclesyd]

Can you come back with little better description of your process?
304 SS would probably surface if their is no area in the system where you could have concentration of the Cl's.

 

[EdStainless]

What temp?
I would seriously consider duplex grades (AL2003 or LDX2101).
They have better strength (use thinner parts) and corrosion resistance.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

 

[strider6]

It would be necessary to know at least the operating temperature and also something else aobut the fluid composition, is there oxygen or other oxidant?

Stainless Steel either SS 304 or SS316 are fully resistant to CO2 corrosion. reagarding the chlorides a general guidelins is to use SS 304 up to 250-500 ppm but this is a function of the operating temperature and other factors...


S

Corrosion Prevention & Corrosion Control