CO2 Corrosion? (material selection)

[shevy]

Dear Eng-Tip comunity,

I had a look on many threads about CO2 corrosion but I couldn't find a an answer on my question. So maybe you can help me and I will be thankful (we dont have to consider the optimization of the process:
we a have a ~ 45 km 16" gas pipeline which is undergoing slugging and subsequently high pressure drop issues. due to this slugging problem we want to separate the water and pump it to the Cenral processing facility.
For pipline material selection I have to calculate the corrosion rate due to CO2 for the produced water pipline. In the gas pipeline we had CO2 concentration of 11 Mole% which is very high (OP:110 bar, OT:45°C and 30000 ppm chloride).
the question is should I consider the whole 11% CO2 also for the water pipeline or there will be less dissolved in the separated water?


thanks in advance
shevy

 

[SJones]

What does the user manual for the CO2 corrosion prediction model that you will employ tell you to use as input for a liquid full system?

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[MortenA]

Without know what model you are using you question is a bit hard to answer - but as Steve says, your software manual should aderss this issue.

Best regards, Morten

 

[shevy]

thanks for your response,

actually I am not able to use any software (not available), my intention was just to use De WAARD formula

regards
Shevy

 

[SJones]

There are at least two pieces of CO2 corrosion prediction software available for free download. They will work on much the same basis: they need the partial pressure of CO2 from the gas phase in contact with the liquid. Assuming that you stick a separator in the system, then you would work with the product of the mole fraction of CO2 in the gas in the separator and the maximum operating pressure of the separator.

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[shevy]

Dear sjones,

thanks you very much for your quick answer,
I will download those softwares
I assume that you proposed "work with the product of the mole fraction of CO2 in the gas in the separator and the maximum operating pressure of the separator" will be applicable for the liquid pipeline downstream of the separator!?

regards
Scherwan

 

[SJones]

Yes

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.