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Stainless steel piping corrosion due to chlorides

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cityjack

Mechanical
Mar 5, 2013
50
US
Good morning all,

I have been tasked with creating a containment system for our piping run that transports Quilon C (Release agent) in solution of IPA from a large storage tank outside to inside the plant. The 1" piping is currently a chemical grade polypropylene over an approximately a 150yd run to the plant. The fear is if the pipe breaks it will spill IPA/Quilon C all over the lawn and outside.

My first lack of chemistry knowledge stab was, why don't we just use a grade of stainless and butt weld everything together. That would certainly be more secure than a plastic pipe that is getting weathered exposed to the elements. That is when I learned that stainless doesn't play well with chlorides. This Quilon C has ~7 % weight in its mixture. In my past life, I have passivated stainless pipes with a citrus acid to transport electrolyte. But we only did this a single time after assembly of all the piping to get it all cleaned. I do not know enough about stainless metallurgy and chromium levels to make a call on a grade of stainless to use. Or better yet, how I can treat the stainless so that I can safely transport this solution from our large tank to the plant. I do NOT want to have to rerun plastic pipe encased in another pipe just for containment.

Any direction would be greatly appreciated.

Thanks guys

Sid
 
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7% in wieght it seems to much chlorides, in that case SS shouldn´t be a good option. Why don´t you use a carbon steel internal linned with plistic?

luis
 
Use a "double Pipe" system with an active leak detection system incorporated.

There are many combinations of materials that could be used for the inner and outer pipe



Inspect and test the system periodically

Stay away from austenitic SS materials .....

MJCronin
Sr. Process Engineer
 
Buying a pre-fab double containment system is a good option. They can both be polymer, the outer one selected for strength and UV resistance and the inner one selected purely for chemical resistance.
That said you should be able to go to the manufacturer of the chemical for material compatibility information. This is a Chromium containing solution (5-9% depending on concentration) with very little Chloride in it. And I suspect that the Cl is bound in a complex (since it has very limited affinity for IPA) so the risk to SS may be very low. You may be able to use 2205 for piping (sch10) and not have any issues. Ask the source.

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P.E. Metallurgy, consulting work welcomed
 
Task: still not a verb.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
 
The formula indicates some Cl (I was looking at the structure). But being high in Cr I find this an interesting animal.
One option is to look up how they make it and what materials they use for handling and storage.

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P.E. Metallurgy, consulting work welcomed
 
Compositepro,

Well it can seem that way when a buzzword is relentlessly parroted by corporate and media hacks (the ones most in need of critical thinking and communication skills, but sadly, most lacking).
Further, it's not helped by online dictionaries and wiktionaries that no longer merely document linguistic evolution but force feed it by racing to validate new words (and get more clicks).
Make no mistake, language is the biggest victim (and the biggest weapon) in the current political and cultural climate.
Meanwhile, my recommendation (going forward!) is to back off the appalling trend of turning every available noun into a verb when perfectly serviceable words are readily available.
I guess I've just architected an off-topic reply.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
 
The double pipe option so solves the environmental deterioration of the plastic pipe as well.
 
MJCronin, thank you sir. I am speaking with Perma-Pipe already. Awesome solutions, thank you again.

....and for you my dear "Ironic". Tasked, tasked, tasked, tasked. I'm running with scissors. Soap box much?

Have a great day all.

Sid
 
Cityjack .....

Please respect us and keep us informed about your final solution.

There are many many materials choices with double pipe systems ..... Which materials and coatings will you go with ?

Will you incorporate a leak detection system ?

Were there any installation problems ??

What design did you use at the terminations ?

Good luck and best regards ....

MJC

MJCronin
Sr. Process Engineer
 
Absolutely MJ,

I'll let you know what I find out and what our tact will be.

Have a great day and thank you again.

Sid

 
I have no tact. In the context of your post, tact should possibly not be in there either.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
 
Evidently not Ironic. But you got me. It was early and hadn't had my coffee yet. I cannot even blame my large fingers this time as the T isn't even close to the K on the keyboard.

Good day to you all nevertheless.
 
We have something in common then, for my typing style has been described as 'hunt and peck'.
Cheers

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
 
Good morning all,

Just wanted to give an update as to the progress of my piping project.

Thank you to MJCronin, I started with his company link of Perma-pipe out of Houston I believe. They were very helpful in looking into my requirements including sds and spec. sheets of my materials. In the end, they referred me to a company called ASAHI out of Boston due to size (one inch) and pipe materials (plastic). I spoke to their technical representative and they indeed had my solution all queued up. They referred me to their distributor here close to me in Charlotte. Long story short, we are going with a 1" polypropylene pipe in a larger 4" containment pipe of also polypropylene. This pipe will be manufactured by ASAHI-America and sold to me out of Charlotte. I will then have my local piping contractor work with Charlotte on the installation.

Lastly, I will be installing a full length leak detection system. I'll update on that more when we are closer to implementation.

Have a good day all.

Sid
 
Eng-tips works!
Glad to see you found a path forward.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
 
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