View Full Version : How much CYA does one puck generate in a 10,000 gal pool
smallpooldad
08-07-2006, 09:24 PM
How much CYA does one puck generate in a 10,000 gal pool?
How much CL does one puck generate in a 10,000 gal pool?
How much calcium does one puck generate in a 10,000 gal pool?
Looking forward to your replies.
chem geek
08-07-2006, 09:35 PM
My answers below in bold assuming you are referring to one 3" diameter Tri-Chlor puck (first answer) or one 3/4" diameter Calcium Hypochlorite tablet (second answer).
How much CYA does one puck generate in a 10,000 gal pool?
Tri-Chlor: 3.33 ppm
Cal-Hypo: 0 ppm
How much CL does one puck generate in a 10,000 gal pool?
Tri-Chlor: 4.06 ppm
Cal-Hypo: 0.10 ppm
How much calcium does one puck generate in a 10,000 gal pool?
Tri-Chlor: 0 ppm
Cal-Hypo: 0.09 ppm
Looking forward to your replies.
smallpooldad
08-07-2006, 09:50 PM
Chem Geek,
Once again thank you. Is it possible for you to supply the equations, when you have time?
I am having to prove a point to my next door neighbours pool persons and them.
If that is not possible I can understand.
Aloha
chem geek
08-07-2006, 10:47 PM
Is it possible for you to supply the equations, when you have time?
I'll try to keep this as brief as possible and hope you or your neighbor know enough about chemistry to believe the math.
Tri-Chlor + 3H2O --> CYA + 3HOCl
See the chemical structure (http://www.oxy.com/oxychem/Products/isocyanurates/literature/ACL%20FAQs.pdf) for Tri-Chlor and CYA and notice that Tri-Chlor has 3 chlorine atoms that get replaced with hydrogen when dissolved in water. These chlorine atoms are Cl+, not chloride (Cl-) so they combine with OH- from water to form HOCl while the H+ from water becomes part of CYA (which is a weak acid).
(8 oz./tablet) * (28.349523 g/oz) / (232.4103 g/mole Tri-Chlor) = 0.9758 moles Tri-Chlor/tablet
(0.9758 moles/tablet) * (129.075 g/mole CYA) * (1000 mg/g) / ( (10,000 gallons) * (3.7854 liters/gallon) ) = 3.33 mg/l CYA = 3.33 ppm CYA
(0.9758 moles/tablet) * (3 chlorine/molecule) * (52.4603 g/mole HOCl) * (1000 mg/g) / ( (10,000 gallons) * (3.7854 liters/gallon) ) = 4.06 mg/l HOCl = 4.06 ppm chlorine
There is no calcium in Tri-Chlor so 0 ppm calcium.
Ca(OCl)2 + 2H2O --> Ca(2+) + 2HOCl + 2OH-
(7 g/tablet) / (142.98366 g/mole Ca(OCl)2) = 0.04896 moles Ca(OCl)2/tablet
There is no CYA in Ca(OCl)2 so 0 ppm CYA.
(0.04896 moles/tablet) * (2 chlorine/molecule) * (73%/100 purity) * (52.4603 g/mole HOCl) * (1000 mg/g) / ( (10,000 gallons) * (3.7854 liters/gallon) ) = 0.10 mg/l HOCl = 0.10 ppm chlorine
(0.04896 moles/tablet) * (73%/100 purity) * (100.0892 g/mole CaCO3) * (1000 mg/g) / ( (10,000 gallons) * (3.7854 liters/gallon) ) = 0.09 mg/l CaCO3 equivalent = 0.09 ppm "calcium hardness"
Richard
smallpooldad
08-07-2006, 10:52 PM
Chem Geek,
Once again thank you.
Hopefully they and I can figure this out.
Aloha