On May 10, 6:09 pm, "SJF" wrote:
"Mike Ruskai" wrote in message

...

On or about Thu, 10 May 2007 00:14:04 -0700 did "SJF"
dribble thusly:

"Mike Ruskai" wrote in message
. ..
I've recently had a water softener put in, and I'm looking to
configure it for the most efficient salt usage with an appropriate
regeneration time.

There is a calculator which you may use to check your calculations at

http://www.qualitywaterassociates.com/sizing.php

This calculator exactly matches my results for 6lb/ft^3 of salt, so
that helps.

If you use KCl rather than NaCl, the salt dosage should be increased about
27% at each recharge.

That seems a bit much. I'll try to verify that number, but at least
it's something to go on.
--
- Mike

Ignore the Python in me to send e-mail.

On the KCl vs. NaCl thing --

I took the number from an unremembered source I considered probably
reliable. Checking, I find that the molecular weight of KCl is 27% greater
than that of NaCl so you would need the extra weight of salt to provide an
equivalent recharge. Since the solubility of KCl at 20 degrees Centigrade
is essentially the same as for NaCl, the water used for brining would need
to be increased 27% to get the extra salt.

For a long retired, and pretty rusty engineer, this exploration into water
softener technology was a pretty interesting exercise -- another where a
perfect answer is not in the cards. As Yogi Berra said, "If you come to a
fork in the road, take it."

SJF

Mike, you need to study the sizing page info and then plug your data
into my calculator. You don't want to go more than 7-9 days between
regenerations, its not good for resin.

SJF, there are two parts to correctly sizing a softener; salt dose
capacity and the SFR gpm of the volume of resin which allows the
softener to be able to remove all the hardness in the water as long as
the peak demand gpm is never greater than the SFR gpm.

Everyone, all softening resin is made in the sodium form, none is made
in the postassium form. All softenrs can use either potassium or
sodium chloride. Softeners only use the sodium or potassium, none of
the chloride. Potassium is not as efficient as sodium, I do not know
why, it simply is, so you must use more potassium than salt unless you
are using a high salt dose. I.E. for 6 lb/cuft (3333 grains/lb), you
must increase by 12% (per the manufacturer).

I size softeners for much greater salt efficiency (and thereby water
use efficiency also) than 6 lbs/cuft and experience says 27-30% higher
salt dose if you are going to use potassium chloride. That and getting
the SFR gpm correct, allows my softeners to remove all the hardness
(produce 0 gpg soft water) between regenerations as long as your peak
demand is never higher than the SFR gpm of the volume of resin in the
tank.

To see how much sodium is added to softened water; the formula is 7.85
mg/l (roughly a quart) per gpg of ion exchange. I.E. 25 gpg * 7.85 =
181 mg of soddium added to roughly a quart of your softened water.

If you look at a loaf of white bread, you'll usually see 120-160 mg of
sodium per slice. An 8 oz glass of skim milk, 530 mg. V8 juice, 560
mg. So unless you have much harder water or you are under a low sodium
or sodium restricted diet, there is little to worry about and IF you
are, you kow how to count your sodium intake and adjust it to your
numbers.

IMO, based on 20+ years in selling and servicing softeners etc., I
suggest using solar crystal sodium chloride and reducing sodium intake
by reading food and beverage labels. That includes well, bottled and
city waters, all contain some sodium naturally.

Gary
Quality Water Associates