I feel this discussion may be drifting from the point somewhat. The gas was a mixture of H2S CO2 and H2O.
The properties of H2SO4 are quite different. For what its worth, H2SO4 attacks steel readily in most concentrations apart from a small temperature/concentration/velocity window which fortunately, or by design, coincides with commercially pure, cooled acid.
My experience with H2S especially in the presence of moisture is that it can be a nasty one to handle, especially under acid conditions. with metals, impurities can have a disproportionate (bad) effect. I used FRP but my temps, pressures and concentrations were far lower than yours. 200C temperature is too hot for HDPE; the plate temperature for welding HDPE is 200-240C.
Suggest you contact Sandvik or similar corrosion resistant steel supplier.
The ASM metals handbook may give some guidance.
.
I assume your application is at an oil refinery. You may get some guidance
from those in that field. Given your pressure/temperature range and the
hazardous nature of the gas, I would be very careful with this one.
Cheers
Steve McKenzie
-----Original Message-----
From: RAKESH PATIL [mailto:rpa@epc.ltindia.com]
Sent: Monday, October 28, 2002 4:42 PM
To: conor.walshe@alceng.com; PipingDesign@yahoogroups.com
Subject: RE: [PipingDesign] acid gas piping material
Ya, I also agree with you conor walshe.
more the concentration of sulphuric acid, less corrosive it is. Dilute acid
needs the material having good corrossion resistance. SS will always be
better.
Actually i didn't see the question. While seeing reply from others i put
mine also and that's why i also mentioned the concentration of acid .
But the service tanmay requires (at 24 bar), i think HDPE will be difficult
to use. It also requires proper supporting arrangement to maintain the
flexibility.
SS or SSNACE will be a good option.
regards,
rakesh
>>> conor.walshe@alceng.com 10/28/02 08:27AM >>>
Have missed the question but, 98% sulphuric acid is not very corrosive once
the piping layout is properly considered, CS would be appropriate, however
the more dilute the sulphuric acid the more corrosive it is and you then
need to look at Stainless steel pipes... and so on, there are of course
flexible piping that could be used but in my background pigging is used and
pipe support locations are predetermined (brown field), hence the
requirement for steel piping.
-----Original Message-----
From: RAKESH PATIL [mailto:rpa@epc.ltindia.com]
Sent: Saturday, 26 October 2002 13:24
To: tsabud@yahoo.com; PipingDesign@yahoogroups.com
Subject: Re: [PipingDesign] acid gas piping material
Hi,
This is regarding our last project where we did the piping for 98.8% conc H2So4.
We used piping material as HDPE and also CS for it.
hope this will help you out.
regards,
rakesh
>>> tsabud@yahoo.com 10/09/02 06:52PM >>>
dear group members
i have not received any answer for acid gas piping
material. if anybody knows something please intimate.
regards
tanmoy
Texas Flange - a good source for information on industrial flanges, all they
ask is for referrals for designs they help with.
877-610-8924.
www.texasflange.com
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Texas Flange - a good source for information on industrial flanges, all they
ask is for referrals for designs they help with.
877-610-8924.
www.texasflange.com
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
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Texas Flange - a good source for information on industrial flanges, all they
ask is for referrals for designs they help with.
877-610-8924.
www.texasflange.com
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Texas Flange - a good source for information on industrial flanges, all they
ask is for referrals for designs they help with.
877-610-8924.
www.texasflange.com
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ Received on Mon Oct 28 04:50:00 2002
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