Can I replace MSRL pipes with SS304 pipes

[ak1965]

We are facing problem with MSRL (Mild Steel Rubber Lined)pipes in Caustic Service. The internal rubber lining is peeling off and choking the piping causing process problem.

Pipe sizes are 3", 4" & 6" and are being used for Caustic service ( 5% and 50 DegC) & H2SO4 Conc. 5 to 10% at ambient temperature.

As no rubber Lined repair service provider is available locally. We are looking forward for a long term solution.

We plan to replace the affected MSRL piping with SS304 piping.

Any limitations from corrosion angle in thsi replacment?

 

[gr2vessels]

SS 304 is OK in 5% caustic solution at 50 deg C, but it will rapidly corrode in 5-10% sulphuric acid solution even at ambient temperature. By the way, how do you mean Caustic service & Sulphuric Acid solutions? Obviously, not together, but are you using the same piping for both services?
Cheers,
gr2vessels

 

[stanier]

Suggest you check out

http://www.nidi.org

for technical papers

 

[ak1965]

Thanks gr2essels,

Ofcourse we are using sulphuric acid and caustic in different pipes in DM plant.

thanks for input on suphuric acid.

 

[ak1965]

I mean, we are using different piping for caustic and H2SO4, but the same MS rubber lined pipes for suphuric acid as well.

 

[MJCronin]

There is a very well written FAQ under the "Chemical Plant Design & Operations" forum relating to this matter

 

[ak1965]

Thanks MJCronin

I see the FAQ and it is well explaning...

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