Why the steam lowers the pH in the process of expansion in turbine equipment?
Why the steam lowers the pH in the process of expansion in turbine equipment?
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Why the steam lowers the pH in the process of expansion in turbine equipment? Could someone show me some literature that best explains this phenomenon?





RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
There may be volatile additives which maintain basic condensate/feed system ph and are carried through the entire loop - boiler to condensate and feed and back to boiler.
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(2B)+(2B)' ?
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
you also need to be specific regarding the the boiler pressure and the sort of water treatment program you have in place.
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
If so, you could precipitate components of the feedwater when the water boils, which could be seen as deposit on the surface of the boiler tubes.
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
That said, typical condensation systems are not exactly designed to produce pure water, and may contain biologicals as well as inorganic contaminants. A pH of 3, which is pretty acidic, would suggest a fairly substantial contamination with ions.
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RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
Most pH probes are better thermometers than they are selective ion measuring tools.
The temperature compensation setting on the meter does not compensate for what is happening in the sample or probe, only the meter.
Between temp errors and the volatilizing of the amine I can see a downward shift.
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
Contamination with ions or error read's interpretation of the pH probes? I'm not sure about that! Actually, I don't believe that! I still believe on phenomenon physical-chemical.
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
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RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
A link on this subject:
http://www.gewater.com/handbook/boiler_water_syste...
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
http://ion.chem.usu.edu/~sbialkow/Classes/3600/Ove...
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RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
Do you already heard about: Kp = equilibrium constant in terms of partial pressure and its relationship with Kc = equilibrium constant in terms of concentration? { Kp = Kc.(RT)^n} ... Then, I think it can explain what I'm telling!
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
It appears (from the net) that at 20oC, equilibrium shows:
for 0.056 mol CO2/L ==> pH = 3.81,
a value decreasing with higher CO2 concentrations.
These pH levels, and lower, are found in drinks such as Coke, Sprite, Pepsi, Dr Pepper, 7 Up, RC Cola, etc.
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
fantastic response given the incomplete description of the problem actually being encountered, pretty soon we can add solar neutrinos and global warming!
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
The chemicals added in the DA have to end up somewhere- what goes in must go out. As the feedwater enters the steam drum some chemicals remain in the boiler water and are blown down to the flash tank via the continuous blowdown line. The high iron content of the boiler water acts as a catalyst to breakdown some of the chemicals The fraction that passes into the steam phase are sometimes thermally cracked in the superheater ( espescially in duct fired HRSG's) and CO2 and hydrocarbons are the end result.
Once the steam finalyy arrives at the condenser , there occurs another split of chemicals- some passes to the precondensate ddroplets , and some chemical amines escape with the noncondensibles to the SJAE or vacuum pump vent. The CO2 forms carbonic acid, and the pH at teh interface between setam and pre-condensate has a lower pH - this leads to FAC of the ACC CS tubes. See papers by Barry Dooley on this issue.
"Whom the gods would destroy, they first make mad "
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
I never insinuated that the pH level of carbonated drinks is due to CO2. BTW, a variety of acids are used beside citric.
BTW you dropped a cero.
RE: Why the steam lowers the pH in the process of expansion in turbine equipment?
Naturally occurring bicarbonate alkalinity in boiler make-up water breaks down into CO2 under boiler conditions. This CO2 is carried out of the boiler harmlessly - until the steam condenses. The CO2 dissolves in the condensate, resulting in a pH of about the same as soda pop.
The requirement for dealkalizers, and whether they are installed before or after the softeners is totally dependent upon local water conditions.