Contact US

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!

*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

Sour oil trap operation?

Sour oil trap operation?

Sour oil trap operation?

Hi, Could someone help me as I am trying to figure out how does a sour oil trap of a centrifugal compressor work. The only information I have is that a sour oil trap basically removes the process gas trapped inside the seal oil and vent it (please correct me if I am wrong) and that it contains a float and orifice etc. What I really want to know is that how do these components come together to separate process gas from oil and what is the purpose of a blow down valve in the trap??


RE: Sour oil trap operation?

Not all contaminated seal oil traps are the same. But you provided some clues to how yours are configured. Seal oil that leaked through the seal has contacted process and cannot, normally be returned to the reservoir. This contaminated oil flows down to the contaminated pots. This flow of oil can be encouraged to keep moving by a slight flow of gas. The gas flow is caused by a vent on the top of the pots that is directed to some lower pressure destination. Most of our pots are vented to flare through a very small orifice.

In some of our pots there are float mechanisms that open automatically on high level to drain the pot to some suitable system. The contaminated seal pots could be said to allow residence time with reduced velocity to allow the oil and gas to separate. Depending on where the oil is discharged, this could be important. This separation occurs at low velocity by virtue of gravity. I don’t know what you are referring to as a blowdown valve. Is it a manual drain for draining the pot to a different destination?

Johnny Pellin

RE: Sour oil trap operation?

Thank Johnny Pellin...The info you provided helped me understand the principle. thumbsup2

RE: Sour oil trap operation?

Johnny Pellin's description was spot on. I've seen a couple of these things taken apart and the internals remind me of the steam traps you see on utility steam systems.

Also, notice that Johnny's description talks about "contaminated seal oil traps", not "Sour Oil Traps". I've often seen them called "sour oil traps" in plants that process sour gas, I think that is to pound home that opening them in that service is dangerous. Both terms refer to the same device (except maybe materials of construction).

David Simpson, PE
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist

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! Already a Member? Login


Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close