High Alkalinity Water, High Sodium, Only Moderate Water Hardness

[Eric]

Hi PeeBee, I think we've reached the point where we differ in opinions.

I don't think you will find any peer reviewed paper on the insolubility of sodium salts, I think anyone capable of doing such a review wouldn't waste their time. My quick search revealed only that sodium bicarbonate was more soluble than sodium carbonate at all temperatures above freezing. Those are used by some brewers with soft water to provide alkalinity because of their solubility. Calcium carbonate will not readily dissolve in water, calcium bicarbonate doesn't exist as a solid, although it is possible to produce liquid calcium bicarbonate from calcium carbonate and water in a sealed vessel under CO2 pressure.

I think the subject of temporary hardness adds little value to a brewer's knowledge. Calcium plays a major role in brewing whether it is present in permanent or temporary form. Magnesium similarly, just with lesser influence. Alkalinity also has a major influence, whether it is in temporary or permanent form, but if permanent, it will not be part of hardness.

KH stands for Carbonate Hardness.

TDS, Total Dissolved Solids used to be measured by evaporating all water and weighing what remained. The remnants were then analysed to determine the ions present.

[PeeBee]

Crikey! I think I've described something for you very wrong? "Insolubility of sodium salts" ... I need to check how I've passed on that idea. Give us a moment (night) I'll straighten that possible miscommunication out.

[Eric]

Crikey! I think I've described something for you very wrong? "Insolubility of sodium salts" ... I need to check how I've passed on that idea. Give us a moment (night) I'll straighten that possible miscommunication out.

Sorry, it should have been sodium carbonates, or base.

[PeeBee]

Okay, I'll see if I can rephrase my question better:

In reactions 'tween solutes where one of the products is insoluble, the reaction continues until all the insoluble product (precipitate) has been formed. A "double decomposition". You know, I find it really depressing when you learn things you've learnt at school have become arcane and retired and you dare not ask how long ago it happened ... the term "double decomposition" is one of those things it seems!

But for this calcium bicarbonate -> calcium carbonate (precipitation) reaction using heat it seems different, "Bru'n Water" even has a calculator that tries to predict how much calcium bicarbonate converts (and so how much boiling can "softens" the water). I.e. the reaction will go so far, and no further.

What's going on and how can I make these "predictions"? And how might sodium interfere?

[Eric]

I think I follow your line of thought with chemistry, but my line of thought more usually follows brewing process, leading to this juxtaposition.

Brewing liquor is mostly composed of 3 major cations, Calcium, Magnesium and Sodium, with anions Sulphate, Chloride and alkalinity in forms of carbonate and bicarbonate.
The proportions of the latter, I read, are determined by acidity, which may depend upon the amount of dissolved CO2. Heating drives off dissolved CO2, raising pH to deplete the bicarbonate of its hydrogen atom and become carbonate. Calcium carbonate present in excess of its solubility will begin to deposit. There will be a level when this too will happen with sodium bicarbonate, but due to the solubility of sodium, it will happen at a saturation level far too high for making beer.

Adding calcium hydroxide to water with calcium bicarbonate will deposit calcium carbonate without removing CO2.
Ca(HCO3)2 + Ca(OH)2 --> 2CaCO3 +2(H20), but a filter may be needed to remove suspended solids and alkalinity may increase if the addition isn't precise.

I've doubts about how predictable reduction in hardness and alkalinity can be by boiling. Graham Wheeler would add add calcium salt(s), boil and be happy with the result. My water comes from magnesian limestone, dolomite, CaMg(CO3)2, there's a bond between calcium and magnesium. I found boiling my water reduced alkalinity vastly less than other hard water brewers reported.

Some use RO water, but for me, all I need to know is what minerals are my water contains, how excessive the alkalinity is for the style of beer I intend to brew, and then decide which acid and salt addition will make a suitable profile.

There will be methods of reducing hardness in ways you suggest, but those are beyond my comprehension too and potentially are outside of means available to most homebrewers and with ion exchange, it will be calcium that deposits and alkalinity that remains.

[PeeBee]

I gave up trying to find the impact of high Sodium values (low calcium) on water for brewing, and the variable effectiveness of boiling on water alkalinity.

The Sodium content only seemingly effects "Hardness", so the solution was just ignore "Hardness" all the more. And "boiling" seems to be such an unpredictable, and very expensive, way to reduce alkalinity, ignoring it, even actively discouraging the technique, seems the best policy with it. I do not need to reduce alkalinity, so a solution to unpredictable boiling was never going to benefit me very much!

So, I've got on and finished the "loose threads" of my water "Defuddler" spreadsheet (including usage instructions) and am testing that ahead of releasing it. Thanks for all the help putting it together.

WaterReportIII.jpg (77.5 KiB) Viewed 2463 times

(The "Defuddler" can indicate the water report it is using is "dodgy" now. In this case, an ion imbalance, large chunks of the "Defuddler", including the "alkalinity text seen here, turns RED. A "tolerance" can be user set on the balance checking ... in this case 35% of the "balanced ion mass" had to be added to get the report to accept it was balanced, and 35% is a very significant quantity! The report was, as I was being told, "cr&p"!).

(The "bicarbonate" value is grey to indicate the "Foetid Mire" had to be involved to extract it. SE Water never bothered to indicate their published alkalinity value was in units of "ppm as bicarbonate" ... most would have to guess.).

[PeeBee]

... The "Defuddler" is getting a bit of enhancement, ...

And one of them was getting some numbers on the "ion balance mismatch. So that previous snippet of the balance check now looks like:

Water Defuddler snip.jpg (41.64 KiB) Viewed 2432 times

The value for "Temporary Hardness" has faded out because it was invalid (more than "Total Hardness" in this "Battle, Kent" example!) and there's an option to set an "acceptable" error% for ion balance calculations (here set at 15%, but that "cr&p" Battle water report had a 30+% error!).

It might seem odd pulling the "ion mismatch" figure from the "Defuddler's" alkalinity/temporary-hardness calculations, but that's just convenience based on how it works.



And do remember, water "Hardness" is the chief arcane mechanism that the "Defuddler" targets for exorcism! Hence displayed faded and grey (the "foetid mire"!).

I haven't updated the "Defuddler" download yet, just some checking to do.

[PeeBee]

The "Defuddler" got its introduction and instructions page too:

Water Defuddler snip2.jpg (304.45 KiB) Viewed 2424 times

It has the "Battle, Kent" water report loaded by default. That's the water that is the subject of this thread. I've been arranging for a sample of this water to come to me for "scrutiny" before posting the finalised version of "Defuddler".

Note I'm fairly rude about water "Hardness". That's only because only a small fraction of homebrewers knows how to wield it accurately. My policy is very much "you don't need it, so don't try to use it". Which gets me into trouble with those who really can wield it (like, err ... Eric!).

[Eric]

Our foremost and formidable mentor directed me to obtain some information for Battle water from a reputable source, and the following is what was extracted by conversion from a list of dissolved solids.
Calcium 55.8ppm, magnesium 4.99ppm, sodium 38.7ppm, sulphate 25ppm, chloride 34ppm and alkalinity 170.1ppm as CaCO3.

The individual ions differ, but the problem you exposed is still present, alkalinity is greater than total hardness. However, the available information suggested temporary hardness was equal to total hardness, probably not, but near enough for our purposes.

[PeeBee]

Cheers Eric! That immediately got thrown into the (new) "Defuddler":

Water Defuddler - Development.jpg (195.39 KiB) Viewed 2366 times

(Picture is 75% of full-scale).

The "Hardness" failure to compute doesn't bother me (sorry! ). (You can see the Defuddler baulking at the hardness figures at the bottom of this picture - the horrid colours I use are intentional!). In fact, that's fine 'cos I'm counting on it being "different" (the "Defuddler" will use "Hardness" for values if asked, but doesn't need them). But apart from the values coming from "somewhere" via you, why should I trust them?

[PeeBee]

Water Defuddler - Development - II.jpg (44.42 KiB) Viewed 2363 times

The balance of calculated "Alkalinity" and the reported figure is very close too. I admit I hadn't cleared out the value for "Nitrates" from the SE Water report; I'll just do that (tap, tap, tap ... tap), there! Hang-on ... 170.1 against 171.53 (Alkalinity in ppm as CaCO3) ... that's suspiciously close!