Condensate pH

Tony Conner_2

...isn't a process HX that's leaking something into your condensate, is there? What about somebody doing some pipe work, who's unknowingly crossed some lines out in the plant?

cbr

condensate pH

currently experiencing high condensate ph (10-11); we have already stopped the condensate treatment application just to avoid further increase in the pH level....however, it's been a month already, still pH is at 10-11;

boilerwater quality is good : Total Solids - 1000 ppm; pH - 10-11; Alkalinity - 700-800; DO = 0; Total Hardness - 0.

what other possible reasons could have caused this high condensate pH?


thanks & regards

cbr

Guy_6

Air

What is the quality of the AIR that the appliance is drawing in? Is it in a hostile enviornment? The boiler may be "washing" some contaminant from itself with the condensate.

Barbarossa

You say you stopped the condensate treatment to permit the pH to drop. I assume this is a 2 pipe steam system with a condensate tank that only sees the return and is not seeing the boiler water also. If so then one of the components of the boiler treatment is likely an amine that will travel with the steam. The pH can indicate the presence of the amine but not its concentration in the return. You should be talking to the treatment supplier to adjust the chemistry of the feed. He should be earning his pay for the product you buy. If any of the assumption I made are wrong then the supplier of the treatment would still be your best bet for answers.

Constantin

I'd contact George

.... at Rhomar Water Systems and talk your problem through. They do a lot of industrial-scale work, so I'm sure they've heard of your problem before. Good Luck!

cbr

as stated

thanks for ur input.... but the 2 Boiler water treatment used is sulfite-based (corrosion control) & phosphate-based (scale control)...however, the condensate treatment (which we discontinued) is amine-based. and this was fed directly to the steam line..... would u say that the system still retains the effect of amine overfeed (if in case) even if feeding has been stopped for 1 month already?

Tom R.

Caustic

Any ph over 9 is definitely harmful to the boiler, causing caustic embrittlement. Hope you find the cause and remove it. Get the ph back to 8.5.

Barbarossa

There are many schools of thought on this and condensate doesn’t buffer well; a little amine will make the pH rise to 10 and an over feed is still about a 10. Test the condensate to be sure there is no Phosphate crossing over to where you are measuring the pH: this can be from priming and steam quality issues and boiler water leaking back into the hot well. If you eliminate the Phosphate in the condensate tank you are pretty much left with an over feed in the past this can take time if your system is tight and you have a high % of return. Your supplier can tell you how to determine the amount of overfeed by seeing how much acid it takes to titer the pH back to 7; this way you can see how fast it is being used up. Let me know how you make out.

Guy_6

oops

My bad,
My past had me thinking of condensing appliances, not steam condensate.

cbr

muchas gracias!

thanks guys!

have not gone through this prob lately...will update u if something comes up... u're not giving up on me, are u?....

cbr

muchas gracias!

thanks guys!

have not gone through this prob lately...will update u if something comes up... u're not giving up on me, are u?....

cbr

condensate pH

hi guys! am back....finally, the culprit had been traced... apparently, there was a carryover of boilerwater due to too high water level....over the desired operating level...the float which was just replaced did not function well...

now, condensate parameter levels are back to normal...

thank you and see you around....

Barbarossa

So how did you check for the carryover. Generally you check the condensate and see if it is positive for the boiler side treatment such as phosphate or SO3 that should not travel with the steam if its quality is good.