alternative to Reverse Osmosis Filter

[Junket]

I have very hard and alkaline water, and I have found that cutting it with distilled water eliminates some of the harshness in my beers and helps to correct my pH. I'm sick of going to the store to buy gallon jugs of distilled water, though. I've read up on RO filters, but I have learned that they waste about 5 gallons of water per 1 gallon filtered. Are there any alternatives to an RO filter, short of distilling?

[JimBrew]

I'm currently looking at getting a complete RO system off ebay. Here's my rationalization: Distillation takes way more energy per gallon than delivering water to you and you flushing 5 gallons for everyone of RO than distilling it. I am studying engineering and have taken a couple classes in energy balances to kind of back up my findings. BTW, if you fill up your jugs at the store (like I do because our water is horrible), than that is also an RO system. It helps to use a pump running on your wastewater backend of your filtration to boost your PSI (look into it on ebay) and lower your wastewater amount.
In anycase, I think its way cheaper to RO your own water for like 2 cents a gallon than pay 30 cents at one of those machines, not to mention all time I spend lugging those jugs to the store. The added bonus is using the water for my brewing.

[DannyW]

What about using 10 cents worth of slaked lime to drop the carbonates out of your water? I was discussing this very thing with a friend of mine the other day and we came across this:

Date: Thu, 23 Oct 1997 20:02:17 +0200
From: "Hubert Hanghofer" <hhanghof>
Subject: Re: Lime as water treatment

A.J. deLange writes in HBD#2537 about the use of lime in treatment of
brewing water. I answered the original question by Grant W. Knechtel
via private email but thought I should re-edit and forward it to the
collective, because I was a bit amazed to read, that the process is
not very common among homebrewers.

As has been noted by A.J. deLange, slaked lime removes
hydrogencarbonates:

Ca(OH)2 + Ca(HCO3)2 -> 2CaCO3 (precipitate) + 2H2O

The process works well with Ca based temporary hardness but doesn't
remove MgCO3 because of its solubility. MgCO3 requires additional
Ca(OH)2 to precipitate: MgCO3 + Ca(OH)2 -> CaCO3 + Mg(OH)2

The method is widespread among Austrian / Bavarian brewers
(geology is based on limestone, water high in temporary hardness).
It's allowed according to Bavarian Reinheitsgebot and even according
to the very rigorous bioland brewing guidlines (...those green
clean bio beers).

...Now let's try a simplified approach:

1) Set up a water treatment cask that holds the whole volume of
brewing water (mashing, sparging).

2) Fill in half the water, add all Ca(OH)2 necessary for the *whole
volume*. Thus some of the Mg will precipitate, too.

Calculation of the necessary amount Ca(OH)2:

grams / Litre = Alkalinity (ppm CaCO3) x 0,74 / 1000
grams / Litre = Alkalinity (mMol/L) x 74 / 1000

grams / US gallon = (g/L) x 3,785

If you have to use CaO (burnt lime), multiply the grams Ca(OH)2 by
0.757 to get the grams CaO, that have to be slaked with water prior
to adding (be careful, much heat may develop, both CaO and Hydroxide
are caustic).

3) If needed, add water salts to adjust water chemistry.

4) Gradually rise the volume by adding more water. Keep rising the
lime by stirring every 10 minutes or so to aid the reaction and help
convert the initially very fine precipitate to a coarser one.

5) *IMPORTANT: Don't rely on the calculated amount. Keep an eye
on the pH. If it's <8 you're done, otherwise add more water!!!*

6) Remove the stirring paddle and let the precipitate settle out for
at least 12 hours. So the whole work is done on the day before
brewing.

7) Rack off the water into your kettle....
Low turbidity is allowed, but you should take care to leave the
sediment behind.

I'm water chemist and could make more efforts, but use this primitive
approach in my brewing for years and am very pleased with the
results. I'm able to produce Pilseners with my tapwater (alkalinity
300ppm CaCO3), adjusting residual Kolbach alkalinity to (*measured*)
negative values.

Notes:

pH-Control (5) is the key factor for this simplification! It's like a
titration of slaked lime with tap-water's HCO3. The drop in pH is
significant, so pH test sticks can be used (I use them at home). I
recommend however, to add 5-10 vol% more tapwater after reaching
pH<8.

After step (2) Mg(OH)2 will precipitate, but gradually re-carbonate
and dissolve when you rise the volume and lower pH. So the split
treatment as described by A.J. deLange should be used, if water
contains more than 20 mg Mg/L. After racking off into the secondary
(...water treatment cask!) proceed from (3).

Hope this helps somebody!

CHEERS &
sehr zum Wohle!
Hubert in Salzburg, AUSTRIA
http://www.netbeer.co.at/beer/

[JimBrew]

Ya, that works if you know the concentrations of your minerals in your water. I guess I like to justify the purchase because I will be drinking alot of this water as well. We go through about two gallons of drinking water each day, so my purchase would be mainly for this, not brewing.