×
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

steam recovery suggestions?

steam recovery suggestions?

steam recovery suggestions?

(OP)
hey guys i've a sizable amount of steam coming out of the atmospheric flash drums and its thought that recovering the steam might be profitable. Aside from passing the steam through a heat exchanger... any other options? The heat exchanger isn't an attractive option is because of its impact on the other heat exchangers down the line. there's quite a bit of steam to condensate -- 20,000lbs/hr!

RE: steam recovery suggestions?

If you are generating your steam at a higher pressure than you are using it at, you could use a thermocompressor (Ejector) to pump up the waste steam to a higher level.

RE: steam recovery suggestions?

Or compress steam via centrifugal compressor to reach some 2 bar abs - assuming you have a use for that. For 20k#/h you should use some 400 kW.

RE: steam recovery suggestions?

There is not much use for atmospheric steam, so if the processes can handle a back pressure, you can get a pressurized flash tank and use the low pressure steam.  A common use is in a dearator if you are near the boiler room.
Here in NYC we do grab some BTU's out of an atmospheric flash tank by running coils through them to preheat cold water.  Here it is not really a heat exchanger but rather a designed flash tank with coils, so it does not effect the backpressure on the condensate.
Hope this helps.

RE: steam recovery suggestions?

The dearator is a great sink. If you have distillation columns with low temperature bottoms or waste water steam strippers, then these are good candidates to soak up low level heat. Lowering the pressure of an existing column to use LP steam could be a big win. LiBr chillers can soak up some low level heat, but chillers will ultimately need to reject heat to a cold utility.

Even better is to insure that heat utilization at higher temperatures is close to the minimum energy requirements (i.e. pinch analysis), and that useful waste heat is recovered before letdown to atmospheric pressure. This will insure minimum flash steam generation.

best wishes, sshep

RE: steam recovery suggestions?

(OP)
Thanks guys. I learnt quite a bit form your suggestions. The reason why we flash it to the atm. is that we want to get rid of the salts and what not in the flashing water. The atm. flashing should not be changed. Right now i'm working on to see if we could connect the vent to a packing/tray tower and try to recover as much clean steam as possible. Maybe that'll work, hopefully there's enough pressure for the steam to go through the tower.

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