Pipeline material for sulfuric acid 1

[ChemicalJABI]

Dear all engineers,

Do you have any ideas about what material can be used for strong sulfuric acid lines (99% w/w).

Can we use simple carbon steel, or do we need stainless steel ?

Any comments would be very helpful

Thank you.

Regards.

 

[EmmanuelTop]

You should be fine with Carbon Steel at ambient temperature and flow velocities below 3 feet per second.
See FAQ from Dupont:

http://www2.dupont.com/Clean_Technologies/es_MX/assets/downloads/Equipment_FAQs.pdf

Dejan IVANOVIC
Process Engineer, MSChE

 

[georgeverghese]

SS or higher alloy grades would be required if there is a risk of contact with O2 and / or water , else CS is okay, as ET says.

 

[ChemicalJABI]

Thank you very much for your replies.

 

[itdepends]

Thanks for getting back to us. Pay careful attention to the reply from George though. Carbon steel is fine- but if you dilute the acid at all (e.g. contamination or flush the line)- expect to have a pipe with many holes.

As a chem eng/metallurgist the first part of any answer I give starts with "It Depends"

 

[ChemicalJABI]

Thanks "itdepends".

We have specified SS finally.

I really aprreciate this Forum.

 

[elridyeng]

Carbon steel is ok here no problems with corrosion and for cost also is lower than SS , we just fabricated one for 98% but in diluted state SS is to be used.

 

[Bernoulli31]

Going over EmmanuelTop's attachment, I read "PVC and CPVC piping is recommended for vent/vapor lines only. They are not recommended for liquid service."
Huh? I work in the semiconductor world, and we see PVC all over the place for Waste drains and chemical supply.


I design aqueducts in a parallel universe.

 

[BootsChemE]

SS is useless, may as well use CS. If you want something much better use Hasteloy. We replaced all of our SS lines after we found severe corrosion. Since we changed to Hasteloy, haven't had any problems yet. If you use SS, I hope you have a schedule 80 pipe at minimum.

 

[EdStainless]

Is there any NOx or SO2? any Cl? any chance of concentration ever dropping below 98%? will the pipe always be full?
At moderate temp (30C) iron and steel will not handle 99% acid without noticeable corrosion.
High Si alloys (both cast irons and stainless grades) work well.
304 will work if there are never any Cl.


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P.E. Metallurgy, Plymouth Tube