×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Sour Service

Sour Service

Sour Service

(OP)
How to determine that you have sour service or seever corrosive environment for a vessel, when the only thing you are provided with is co2 content of the vapor?

RE: Sour Service

Sour service refers specifically to the effects of H2S - if you do not have any, then sour service is not an issue.
CO2 corrosion is a different issue and many companies, like Shell for example, have developed assessment procedures for CO2 service.

RE: Sour Service

Experience or Corrosion Testing in actual or simulated environment?

RE: Sour Service

A corrosive environment said to be sour if H2S(hydrogen sulphide) is present in that environment. If there is none,the environment is not sour.
In other to determine the corrosivity of the flüid in a vessel a knowledge the % composition of the vessel's content is required.The following substances are corrosive:CO2,SO2,Chlorides,H2S; acid forming salts and gases in general. The Oxygen content of the vessel aslo determines corrosivity. The temperature of the environment also plays important role. others such as the level of agitation, if liquid has effect,etc  

RE: Sour Service


1.0  NACEMR0175: Defines partial pressures of H2S that
     would term the service "sour"  exceptions to low
     pressure systems below 235 psig. "0.05 psia <- if
     memory helps"

2.0  Other forms of hydrogen damage such as HIC are not
     addressed by NACEMR0175; several IOCs consider
     sour service in liquid phase if H2S content exceeds
     50 ppm.  Noting that HIC failure has occured at
     concentrations as low as 20 ppm and the phenomena is
     not pressure dependent as is the case with Sulphide
     Stress Cracking.  

I believe, a new NACE Std was recently issued NACEMR0130 which is comprehensive is addressing sour service.

Cheers
 

RE: Sour Service

Full knowledge of the chemistry of the process fluid, and the temperature/pressure conditions are required to determine severity of corrosion. For example, will water vapor condense? I have had carbon steel pipe in sweet crudes that pitted at 0.120" per year because water condensed at approximately 140 F - 150 F just beyond the christmas tree. Corrosion was limited to about 300 ft of piping. Well analysis indicated small water content and < 2% CO2.  

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources