×
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

Humidification with pure water and corrosion

Humidification with pure water and corrosion

Humidification with pure water and corrosion

(OP)
We had an application which used steam generated from a "clean steam" generator for humidification.  The steam generator used DI water as feed.  After a relatively short (?)period of time, the galvanizing on the ductwork downstream of the humidifier was almost gone.  There had been some problems with the humidifcation valve being open when it should not have been; however, the corrosion took place so quickly that the conclusion was that the water was "too" pure.  I understand that high purity water can be be ion hungry, but I have never seen sources on humidification warn against too high a quality water or state a high end specification?  Could high purity be the issue here, and if so any thoughts on what the max purity should be?

RE: Humidification with pure water and corrosion

Greg, that sounds like a reach. I would guess the problem would be more related to a high limit humidistat (or one not located well or set too high), too high a steam pressure creating excessive vapor trail, or impingement due to vapor trail obstruction.

I would think that less clean steam might have more volatiles entrained in the water vapor which would tend to accelerate corrosion, not reduce it. The way to treat a steam system and reduce corrosion is to add a volatile pH additive like morpholine, but you definitely don't want a volatile additive in a humidification system.

Replace the rotted section of duct with stainless. Look at the drainage, high limit humidistat, steam pressure, an vapor trail path. Good luck with this, -CB

RE: Humidification with pure water and corrosion

Greg!

Check the dryness of the steam. IMO you should not have a problem unless your steam is wet. Run the humidifier and check for traces of water (or moisture) on the duct internals.

Check www.armstrong-intl.com website for humidifier handbook. They specified a method of jacketing steam supply pipe to reduce wetness.

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