---

	FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
		Digest Janitor: pbabcock at hbd.org


***************************************************************
        TODAY'S HOME BREW DIGEST BROUGHT TO YOU BY: 

                 Sponsor The Home Brew Digest!
     Visit http://www.hbd.org/sponsorhbd.shtml to learn how
			 
    Support those who support you! Visit our sponsor's site!
********** Also visit http://hbd.org/hbdsponsors.html *********

DONATE to the Home Brew Digest. Home Brew Digest, Inc. is a 
501(c)3 not-for-profit organization under IRS rules (see the
FAQ at http://hbd.org for details of this status). Donations
can be made by check to Home Brew Digest mailed to:

HBD Server Fund
PO Box 871309
Canton Township, MI 48187-6309

or by paypal to address serverfund@hbd.org. DONATIONS of $250 
or more will be provided with receipts. SPONSORSHIPS of any 
amount are considered paid advertisement, and may be deductible
under IRS rules as a business expense. Please consult with your 
tax professional, then see http://hbd.org for available 
sponsorship opportunities.
***************************************************************


Contents:
  Sodium/Chloride ("A. J. deLange")


* * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*   Beer is our obsession and we're late for therapy!   *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * *

NOTE: With the economy as it is, the HBD is struggling to 
meet its meager operating expenses of approximately $3500
per year. If less than half of those currently directly
subscribed to the HBD sent in a mere $5.00, the HBD would
be able to easily meet its annual expenses, with room to 
spare for next year. Please consider it.

Financial Projection As of 21 May 2010
       Projected 2010 Budget  $3505.65
 Expended against projection  $ 874.75
Projected Excess/(Shortfall) ($2080.54)

As always, donors and donations are publicly acknowledged
and accounted for on the HBD web page. Thank you

 
Send articles for __publication_only__ to post@hbd.org

If your e-mail account is being deleted, please unsubscribe first!!

To SUBSCRIBE or UNSUBSCRIBE send an e-mail message with the word
  "subscribe" or "unsubscribe" to request@hbd.org FROM THE E-MAIL
  ACCOUNT YOU WISH TO HAVE SUBSCRIBED OR UNSUBSCRIBED!!!**
IF YOU HAVE SPAM-PROOFED your e-mail address, you cannot subscribe to
  the digest as we cannot reach you. We will not correct your address
  for the automation - that's your job.

HAVING TROUBLE posting, subscribing or unsusubscribing? See the HBD FAQ at
http://hbd.org.

LOOKING TO BUY OR SELL USED EQUIPMENT? Please do not post about it here. Go
instead to http://homebrewfleamarket.com and post a free ad there.

The HBD is a copyrighted document. The compilation is copyright 
  HBD.ORG. Individual postings are copyright by their authors. ASK 
  before reproducing and you'll rarely have trouble. Digest content 
  cannot be reproduced by any means for sale or profit.

More information is available by sending the word "info" to 
req@hbd.org or read the HBD FAQ at http://hbd.org.

JANITORs on duty: Pat Babcock (pbabcock at hbd dot org), Jason Henning,
                  and Spencer Thomas



----------------------------------------------------------------------


Date: Tue, 25 May 2010 09:41:21 -0400
From: "A. J. deLange" <ajdel at cox.net>
Subject: Sodium/Chloride

Dave asked whether there is an easy way to remove sodium and chloride 
ions from softened water. Easy? Relatively. Inexpensive? Depends on your 
definition but RO potentially qualifies. One can buy an 11 gallon per 
day RO system from Home Depot for  $279 (and lots of other 
manufacturers, stores, websites... list lower priced units of around or 
even greater than that capacity). But why would you want to use a 
softener in the first place? It doesn't "remove" anything but rather 
only replaces polyvalent ions (calcium, magnesium, iron, strontium...) 
with equivalent amounts of (monovalent) sodium. Chloride is unaffected 
(except perhaps for minimal amounts from residual brine) as are 
bicarbonate, sulfate, nitrate.... If your goal is demineralized (or 
largely demineralized) water the task is of the same magnitude at the 
output of the softener as it would be if the softener were not used. Why 
not just feed an RO unit directly from the mains? It turns out there is 
a reason. If the water is hard (and we would'nt be having this 
discussion if it weren't) there will be a gradient of calcium ions 
concentration perpendicular to the membrane surface increasing in the 
direction of the membrane. If the hardness is temporary (carbonate) 
there will be a carbonate ion concentration gradient as well and, 
depending on pH, hardness, alkalinity, and recovery rate the 
concentrations of calcium and carbonate ions can exceed the solubility 
product close to the membrane surface with resultant precipitation and 
blockage. If the calcium has been removed by a softener then obviously 
this problem is solved (and it will be some other salt which will limit 
allowable recovery such as barium sulfate even though your water, we 
hope,  contains only miniscule amounts of barium).

So there is a reason to use a softener with an RO unit and, IMO, that's 
the only job for a softener in a brewery (except perhaps boiler feed). 
That said, if you go to HD, buy an RO unit and just hook it up to the 
mains you will probably be fine. I had two of these units in service 
(brewing only) for 4 years in one case and 5 years in the other on 
nominally hard water (about 110 ppm as CaCO3 - mostly temporary) and 
never changed out the membranes because I didn't have to. I'm on a well 
so my pH is low (that helps) and these GE units have low, fixed recovery 
(that also helps) of about 17%. On checking the GE manual for the 
recovery I found that they too recommend a softener if you hardness is 
greater than 10 gpg (about 179 ppm) and your pH > 7. That increases to 
about twice that level of allowable hardness at pH 6.7; three times that 
a pH 6.3 and so on. The manual also says the consequences of not using a 
softener above these levels is shortened membrane life. In the system 
which replaced those small units I feed softened water and feel quite 
comfortable operating it at a recovery of around 40% (which should make 
all you environmental types feel all warm and fuzzy inside).

I'm not sure I understand why Martin would favor nanofiltration over RO 
for the likes of us. They will block the polyvalent ions (thus softening 
the water and decarbonating it, getting rid of sulfate and nitrate) but 
let the monovalents through so if deionized water is the goal additional 
processing would be required to get rid of the monovalents. I guess they 
are easier to clean but as I noted above I have never had to clean an RO 
unit. On an industrial scale I'm sure things are dramatically different 
and the processing methods chosen are determined by the particulars of 
the feed water chemistry, the requirements for the processed water and a 
whole lot of other considerations which include not only the capital 
costs (which he mentioned as being high) but operating costs, 
concentrate disposal and on and on. I know nanofiltration is becoming 
popular among water authorities these days but don't see it for 
homebrewers. But really, I know almost nothing about nano systems.

A.J.




Return to table of contents

---