×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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

Steam Rates For Low Pressure Flares
2

Steam Rates For Low Pressure Flares

Steam Rates For Low Pressure Flares

(OP)
I'm after a guideline on the ratio of steam to flare gas required for smokeless operation of a low pressure continuous flare.

RE: Steam Rates For Low Pressure Flares

I think theres something i API 521

Bset Regards

Morten

RE: Steam Rates For Low Pressure Flares

Check out API 521 as Morten suggests.  

I believe the steam rates vary from about .1 lb steam/lb HC up to about nearly 1:1 ratio depending on the gas in question.  Some HCs burn essentially smokeless (methane) while olefins and other unsaturates can be very difficult to burn smokeless (but can be).

RE: Steam Rates For Low Pressure Flares

2
Flare steam rates, to suppress smoke, are a function of the type of gas which you are burning and the design of the flare tip itself.
In general the steam works in three different ways.

Primarily it cools down the core of the flame so that the "cracking" reaction is suppressed and delayed and the carbon doesn't form until the outer edges of the flame so that it can't grow to unburnable proportions.
Then there's the mechanical mixing and turbulence which it introduces into the gas/steam/air mixture which helps to promote more rapid conversion by bring the oxygen into more intimate contact with the "cracking" gas.
Finally, there is some benefit from the addition of the OH- radical into the mix which sweeps up some C+ into -CHO which is a gaseous radical rather then the C-C-C-C which is a solid.

Having said all this the range of requirements starts at roughly 0.2 w/wt for light paraffinic materials, into 0.35 - 0.45 for refinery type mixtures and developing beyond 0.6 wt/wt for aromatic and olefinic mixtures.  These latter gases all have heats of formation which are intrinsically positive and therefore do not benefit from the cooling as much as the aliphatics.

Another factor is the flare tip diameter because it influences the flame diameter and the dwell time until the gas meets the air.  Bigger flare tips use more steam than smaller tips for the same gas.

Hope this helps you.
If you're really stuck let me know.

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



News


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