Carbon steel for deaerated water pH=9.2 O2=0,02 mg/l 109 deg.C

[EnterYourName]

Hello,
Please give a piece of advice: can water with 0.02 mg/l O2 content (0.2 ppb) be considered deaerated and can carbon steel be used for in this case (the service is boiler feed)?
Water temperature is 109 C (219 F)

 

[moltenmetal]

0.02 mg/L is 20 ppb, not 0.2 ppb.

Is this sufficiently de-aerated for a carbon steel boiler? Depends on the boiler pressure/temperature- if it's very high, it may not be OK- others more knowledgeable can advise you. For the feed water lines CS should be fine.

 

[strider6]

Usually water is considered as de-aerated if the oxygen content is below 10-20 ppb.
There is a very good internet guide on corrosion by GE, this is an absract:
"The consensus is that feedwater oxygen, iron, and copper content should be very low (e.g., less than 7 ppb oxygen, 20 ppb iron, and 15 ppb copper for a 900 psig boiler) and that pH should be maintained between 8.5 and 9.5 for system corrosion protection."

http://www.gewater.com/handbook/boiler_water_systems/ch_11_preboiler.jsp

corrosion protection

hope this can help u
S.

Corrosion Prevention & Corrosion Control

 

[EnterYourName]

Thanks everybody for your replies!