Water Alkalinity, Ph, and chemical dosing.

[WSUgrad]

I have raw water characteristics of a public water supply (attached). Is there a way to determine the alkalinity and Ph from these characteristics? If so, can someone explain to me. I would definately like to learn. Google has provided some chemical equations that make my head spin (likely because no one is there to explain it in simplified terms).

My goal is to make a spreadsheet to determine all of the above.

The last thing I would like to learn about is chemical dosing. Knowing my raw water characteristics and the treatment goals, how do i determine chemical feed rates of lets say polyphosphate? orthophosphate? KMnO4? etc..

Any help is appreciated.

 

[shahyar]

You need to have Carbonate(CO3=) and Bicarbonate(HCO3-) concentrations (in mg/L as CaCO3) and then you can calculate Total Alkalinity:
TAlk = CO3= + HCO3- + OH-
You can assume OH- is negligible or calculate it if you have Ph in your analysis.
Hope this help

 

[bimr]

If you convert to calcium carbonate equivalents, the cations (calcium, magnesium, and sodium) will equal the anions (bicarbonate, nitrate, chlorine). The alkalinity can then be determined as the difference.

The pH can not be determined unless you know the CO2 content.