Caustic Soda percentage

[a1987]

Dear Sirs

I would like to know how the percentage of caustic soda influence the choice of a pump... in particular, change anything if the percentage of caustic soda dissolved in water is 15% or 25%? in my opinion, yes it does...but i would like to have your opinion.

thanks a lot

 

[cloa]

What temperature?

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[a1987]

30 °C pumping temperature..
the pump are installed outdoor and temperature is -28 °C

 

[25362]

May be this link will give you sufficient properties of NaOH solutions for your consideration:

http://msdssearch.dow.com/Published...soda/pdfs/noreg/102-00011.pdf&fromPage=GetDoc

 

[micalbrch]

15 or 25 % at 30 °C does not make such a big difference. The wetted parts should not get bridle due to the low ambient temperature but the chemical compatibility is the same for 15 and 25 %. What is suitable for 15 % will withstand a 25 % solution, too. The specific gravity changes from approx. 1.15 to 1.25. That could have an effect if your pumps is sized borderline.

 

[bimr]

Caustic pumps typically are designed to use 20% solution because the freezing temperature of caustic is lowest at 20% concentration.