brainstorming
Chemical
Does any body can help me in choosing the material of a sulphuric acid service?
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Sulphuric acid piping
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pipingdesigner
Mechanical
Brainstorming,
I took this from I hope it helps.
Sulphuric acid
Piping to the process should be of schedule 80 carbon steel, or schedule 40, 316-stainless steel with slip on welded flanges.
Piping should be sized for an acid velocity of 3.5 feet/second or lower to minimize the erosive effects of the acid.
Care should be taken at both the design and operation stages to avoid liquid full sections of pipe between closed valves since the hydrogen produced by steel corrosion can cause dangerous pressures especially in warmer weather.
Quarter turn plug valves have been found to give good service with sulphuric acid.
The recommended type should have a flanged end ductile iron body with an alloy 20 plug or Teflon encapsulated plug and a Teflon lining.
Gasket material should be Teflon.
pipingdesigner
I took this from I hope it helps.
Sulphuric acid
Piping to the process should be of schedule 80 carbon steel, or schedule 40, 316-stainless steel with slip on welded flanges.
Piping should be sized for an acid velocity of 3.5 feet/second or lower to minimize the erosive effects of the acid.
Care should be taken at both the design and operation stages to avoid liquid full sections of pipe between closed valves since the hydrogen produced by steel corrosion can cause dangerous pressures especially in warmer weather.
Quarter turn plug valves have been found to give good service with sulphuric acid.
The recommended type should have a flanged end ductile iron body with an alloy 20 plug or Teflon encapsulated plug and a Teflon lining.
Gasket material should be Teflon.
pipingdesigner
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brainstorming
Chemical
pipingdesigner
good infor.
I passed to my colleague and hope it would help
I will come back to you once I get feedback from my colleague
Thank you
good infor.
I passed to my colleague and hope it would help
I will come back to you once I get feedback from my colleague
Thank you
Note that material selection is highly dependant upon the acid concentration - sometimes in counter-intuitive ways.
I'd be careful using carbon steel. If you do so, note that the Sch 80 piping suggested above is a corrosion allowance and you will lose material every year.
The conservative (but expensive) route is Alloy 20.
Good luck
I'd be careful using carbon steel. If you do so, note that the Sch 80 piping suggested above is a corrosion allowance and you will lose material every year.
The conservative (but expensive) route is Alloy 20.
Good luck
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brainstorming
Chemical
It is about 90% and brought in trucks for unloading.
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brainstorming
Chemical
Honestly speaking I am not evaluating this material but my friend is.
I asked him about it and told me this purity level!
Once I get feedback from him, I will let you know.
Regards
I asked him about it and told me this purity level!
Once I get feedback from him, I will let you know.
Regards
KenShumway
Mechanical
Carbon steel is fine for sulfuric acid in the 93% to 98% range that it is normally shipped at and is generally at a temperagture below 100 degrees F. It isn't likely that the truck or tank car is able to withstand more dilute acid than this. However, if your acid concentration is really as low as 90% concentration, you might have a problem with carbon steel. The metalurgical requirements for sulfuric acid at various concentrations is really variable. At 90%, you might need to use alloys with chromium and nickle or a nickel/molybdenum alloy of some type.
Ken Shumway
Ford, Bacon and Davis, LLC
Ken Shumway
Ford, Bacon and Davis, LLC
So many recommendations and no one mentions plastics. PTFE, PVDF, and PP lined steel can all be used - Liner differences based upon acid concentration and temperature.
This guide is pretty comprehensive and may help..
FYI, HCl & H2SO4 are the most common applications for plastic lined pipe
This guide is pretty comprehensive and may help..
FYI, HCl & H2SO4 are the most common applications for plastic lined pipe
recoveringEngineer
Mechanical
Info above on the concentrations is good. Also note, sulphuric acid won't likely be used at these concentrations. Sulphuric acid is particularly hard on stainless or carbon steel during the mixing process.
I recall a case where the acid mixing station for the demineralizer had to be replaced after about 2 years of operation due to an eroded hole in a 1x2 reducer. The replacement piping only lasted 2 weeks! The welds were eaten away.
It turned out the initial piping was Alloy 20 and the replacement was 316SS.
Donald Blachly, PE
I recall a case where the acid mixing station for the demineralizer had to be replaced after about 2 years of operation due to an eroded hole in a 1x2 reducer. The replacement piping only lasted 2 weeks! The welds were eaten away.
It turned out the initial piping was Alloy 20 and the replacement was 316SS.
Donald Blachly, PE
brain,
See:
and, an excellent reference:
hacksaw.....
The 98% is a common commercial grade, and is one of the chemicals most widely used in industry. It is shipped by tanker and truck all over the USA
Come back with your final system design
MJC
See:
and, an excellent reference:
hacksaw.....
The 98% is a common commercial grade, and is one of the chemicals most widely used in industry. It is shipped by tanker and truck all over the USA
Come back with your final system design
MJC
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