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Liquid CO2 piping design 4
- Thread starter PSP113
- Start date
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- #3
Montemayor
Chemical
PSP113:
when I was in the business of producing and distributing food grade Liquid CO2 for Liquid Carbonic, we simply used ordinary carbon steel pipe and fittings.
We never had a complaint or any problem.b I don't see a reason why you should also.
NACE Corrosion 2001, Paper 01042
Steve Jones
Materials & Corrosion Engineer
Steve Jones
Materials & Corrosion Engineer
Montemayor
Chemical
I believe there is some misunderstanding about this query.
Liquid Carbon Dioxide is a saturated liquid at the conditions of 250 psig and approximately -8 oF. This saturated liquid is essentially totally anhydrous (it contains no water). All CO2 stored or distributed at these conditions (which is the generally standard, industrial method) is previously dried in fixed-bed adsorbers to an average water content of 1.0 PPM (or less) prior to being liquefied. As a result of this process, there is no plausible reason to design for - or expect - any corrosion from so-called "carbonic acid" (a combination of CO2 gas and water - which IS corrosive). All manufacturers and distributors of bulk Liquid CO2 handle this product in standard, insulated. (usually A516 steel) "bullet" type tanks and carbon steel pipe.
NACE does not (& has never entered) into this application. NACE's understandable concern would be applicable if we were dealing with a corrosive fluid. However, pure, anhydrous, LIQUID CO2 IS NOT A CORROSIVE FLUID. That has been a proven fact for as long as I've been in that business. I don't believe there is any need for concern with corrosion in this relatively benign operation.
If the liquid CO2 has water in it, then that's another story. But the OP has not stated that.
My mistake - on my previous reply. For some reason I had Liquid Nitrogen on the brain - thus the copper comment.
For CO2, I am aware of a carbon vessel failure from a rapid depressurization and resulting temperature drop beyond the minimum temperature of (-) 20 degF for carbon. While press/temp are maintained this would be a non-issue, I also consider Murphy an optimist.
For CO2, I am aware of a carbon vessel failure from a rapid depressurization and resulting temperature drop beyond the minimum temperature of (-) 20 degF for carbon. While press/temp are maintained this would be a non-issue, I also consider Murphy an optimist.
Dear psafety, May be I am less knoledgable than you,but I think that Many Carbon steel LPG storage bullet during rapid vaporisation are subjected to temperatures lower than -20F (Probably can withstand -40F by design)
Best Regards
Qalander(Chem)
Best Regards
Qalander(Chem)
Qalander,
The term "bullet" I'm not sure of, I am referring to large Storage Vessels.
Yes, you are correct subjected to less, but most become brittle slightly colder. Add an impact condition (yes, it can happen and it did).
Sorry:
I should not get OFF Topic the question from the OP pertains to the piping; my apologizes.
The term "bullet" I'm not sure of, I am referring to large Storage Vessels.
Yes, you are correct subjected to less, but most become brittle slightly colder. Add an impact condition (yes, it can happen and it did).
Sorry:
I should not get OFF Topic the question from the OP pertains to the piping; my apologizes.
Montemayor
Chemical
The subject of potential carbon steel embrittlement in CO2 service due to rapid depressurization was discussed in thread:
Although this is not the topic of this discussion, it still may be helpful in designing carbon steel equipment for liquid CO2 service.
Although this is not the topic of this discussion, it still may be helpful in designing carbon steel equipment for liquid CO2 service.
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- #11
PSP113
What is the application? Food or CO2 capture / sequestration.
If it is the former then Montemayor's advice is top notch.
If you are using the piping for CO2 capture / sequestration, then it is unlikely that the water content is reduced to 1 ppm. That said, carbon steel pipework and fittings is applicable for "dehydrated" CO2. For wet CO2 where there is a chance of liquid water being formed (during normal operation or during shutdown conditions) then stainless steel may be required (particularly on compressor pipework)
What is the application? Food or CO2 capture / sequestration.
If it is the former then Montemayor's advice is top notch.
If you are using the piping for CO2 capture / sequestration, then it is unlikely that the water content is reduced to 1 ppm. That said, carbon steel pipework and fittings is applicable for "dehydrated" CO2. For wet CO2 where there is a chance of liquid water being formed (during normal operation or during shutdown conditions) then stainless steel may be required (particularly on compressor pipework)
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- #12
I think its important to establish the application before addressing the materials issue.
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"Pumping accounts for 20% of the world’s energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic (Note: Make that 99.99% for pipeline companies)
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"Pumping accounts for 20% of the world’s energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic (Note: Make that 99.99% for pipeline companies)
- Thread starter
- #13
Well now is it then? OK ... you'll want to see this,
**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic (Note: Make that 99.99% for pipeline companies)
**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic (Note: Make that 99.99% for pipeline companies)
Just turned this one up. Has some more details I'm sure you'll find usefull.
"At some point in the injection system, there is a point at which CO2 and water will occasionally mix and present a potential corrosion problem. Since CO2 is not corrosive in the absence of water, a common principle is to keep the fluids separate nearly right up to the injection well, so very little lined steel or stainless steel pipe is needed on the surface. Only short sections downstream of the merging of the CO2 and water lines, where the choke and meter are located, need to be protected."
**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic (Note: Make that 99.99% for pipeline companies)
"At some point in the injection system, there is a point at which CO2 and water will occasionally mix and present a potential corrosion problem. Since CO2 is not corrosive in the absence of water, a common principle is to keep the fluids separate nearly right up to the injection well, so very little lined steel or stainless steel pipe is needed on the surface. Only short sections downstream of the merging of the CO2 and water lines, where the choke and meter are located, need to be protected."
**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic (Note: Make that 99.99% for pipeline companies)
and this,
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"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)
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"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)
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