Chemicals for pH correction

[Watro]

We are working on a Condensate polisher unit and require pH correction system at the outlet to raise pH up to 9.0 from 6.5
The conductivity at the outlet of CPU unit is <0.1 mS/cm
What are the typical chemicals used for pH correction. Is ammonium hydroxide an option?
What is the Commodity chemical name, typical concentration, dosing concentration, dosage rate for a flow of 225 m3/hr
Also advise the material typ used for such chemicals

Thanks
NM

 

[ashtree]

Before commenting can you confirm your pH adjustment requirements.

You have said you want to raise the pH from 9 to 6.5. That is actually lowering the pH and for this you would need an acid. Ammonium hydroxide is an alkali and would raise the pH.

If you do in fact want to raise the pH from 6.5 to 9 there are many options with sodium hydroxide being the first most obvious choice. Ammonium hydroxide may work but it would not be the obvious choice.
It is impossible to give you any estimate of the likely volumes or concentrations unless you can provide a chemical analysis of the water to be treated.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[ashtree]

I missed your comment about the conductivity of the water. Just want to confirm that the units are millisiemens/cm.

It is still not possible to give you an accurate dosage to adjust the pH as you desire but with water. However with that purity as an order of magnitude it is likely to be less than 10 milligrams per liter of sodium hydroxide required to achieve pH 9.0.

It would be very easy to test this by titration.


Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[Watro]

Hi Ash

The plant is for an existing power plant and they are using Ammonium Hydroxide for boiler feed.
pH to be raised from 6.5 to 9. All other condensate parameters viz; Na, Cl, SO4 will be less than 5 ppb
Unit in MicroS/cm

 

[bimr]

If you are using an All Volatile Treatment chemical program, pH is typically maintained between 9 ~ 10 with the addition of ammonia. Obviously, this would have to be coordinated with your chemical program.

Technical Guidelines

Figure 2 in the Emerson technical paper shows the concentration of ammonia at various pH values.

Emerson

 

[ashtree]

Ammonia hydroxide is the obvious choice in this circumstance.
It would have been nice to have all the information in your second post in the first post as well.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[QualityTime]

for dosage calculations look at getting Alkalinity: pH Changes with Temperature for Waters in Industrial Systems Hardcover – Nov 12 1986 by A.G.D. Emerson (Author)

Also, you can get a university professor to do the calculations