Iron concentration of Boiler Water

[gladkenn]

Can any body help me regarding our boiler water system. Iron concentration and low pH predominates our condensate from the heat exchangers. Any advise as to how we would be able to prevent it from happening. We have tried demineralized water and softened water already for make up. Still we could not prevent it from having iron concentration. We suspect leaking already at HE but the treatment of chemicals were not really reliable from our water treatment specialist.

 

[metengr]

You need to elevate the pH to about between 8.5-9 by using a boiler feedwater chemical treatment program. The low pH does not promote stability of a protective oxide layer on carbon steel, thus corroding the surface of the steel and resulting in iron contamination. This protective oxide layer is called magnetite, and is stable in the high pH range mentioned above.

There are plenty of web sites that contain information on boiler feedwater treatment programs.

 

[gladkenn]

metengr,

Can you guide me through the website just mentioned?
Thanks


gladkenn

 

[25362]

You may start with, for example:

http://www.lenntech.com/boiler/boiler-water-treatment.htm

 

[abcmex]

high iron content in condensate indicates a probable corrosion process on-going!.

A low pH condensate may indicates that:
-you need a volatile treatment (NH3, Hydrazine etc.)
or
-your system has a lot of traped air or it get contaminated with air intrusion.
or
-you have a corrosive leak

A reputed chemical company like NALCO, GE or others can help you if you do not have the required knowhow.

Nalco has a written a good manual which you can buy by internet (

http://www.Amazon.com?).

rgs

 

[davefitz]

There have been some advances in the field of feeedwater treatment, mostly as fallout from the use of the combined oxygenated treatment method used in once thru steam generators.

For the use of standard low O2 fedwater treatment, the pH from 8.5-9.2 is typical, but it is also essential to retain an O2 content of about 2-4 ppb O2 downstream of the feedwater heaters. This insures that there is not excess hydrazine or excess oxygen scavenger in the condensate, which would promote corrosion of the magenetite as badly would too high an O2 content.