Alkalinity/pH and salts again!

[aamcle]

This is doing my head in!

Please check my water adjustment procedure with respect to Alkalinity/Residual Alkalinity.

1. Get a profile for my water, it's usualy about 110 ppm as CaCo3 Alkalinity, also listed are Ca, Mg, CL, So4, Na and others.

2. Decide on the water profile I want to use eg Burton-upon-Trent or Munich or....

3. Use a calculator usualy Brewersfriend. I always enter the grain bill into the calculator.

4.I then use the calculator to determine how much ams/crs I need to adjust the pH and what salts I need to add to match the target water as closely as possible.
There have been occasions were I have had to use ro water to reduce the overall salts concentration.

5. Use the calculator to acidify the sparge .

Usualy this will get me between pH 5.2 and 5.4 but I check the pH with a meter and make any minor adjustments about 10 mins into the mash.
It is very unusual for the pH to change more than a little during the mash.

I have been following that procedure for years but Alkalinity and Residual Alkalinity have raised their heads again and always manage to confuse me.

If the water profile is right ie the correct amounts of Ca, So4 and so on are there and the pH is right surely its job done?


Thanks All.

And thanks for putting up with yet another water post.

 

[doug293cz]

Starting water alkalinity (along with the grain bill) is needed to calculate mineral and acid additions needed to achieve the target mash pH. Residual alkalinity can be ignored. If your Ca, SO4, and Cl levels are in the desired range, and the mash pH comes in within an acceptable range, that's all you need to worry about.

Brew on

 

[aamcle]

That is exactly what I thought and what I aim to do. Every so often Alkalinity especialy RA gets thrown about and sadly confuses me.


Thanks.

 

[Peebee]

Aamcle? From Newton-le-Willows (UK) I presume?

As @doug293cz said: "Residual alkalinity can be ignored.". One less to worry about!

As for "Alkalinity", now that is important, especially for calculators to predict mash pH. You need a good value from your report, 110ppm ("as CaCO3", that is fairly low, and they do have a preference for "as HCO3" over here, as do I, which will be 110x1.22 or 134.2ppm ... remember the magic number of 1.22). Mine is 20.8ppm as CaCO3 (25.4ppm as HCO3) and causes me trouble because the value (and therefore mash pH value) jumps about. Same with you?

I'm currently messing with one of these tools:

Hellish expensive (80 quid), but the popular "Salifert kit" is less convenient and doesn't work below 300ppm no longer (and I haven't an alternative to suggest.).

Working with "Alkalinity" is much easier/better than old fashioned "Hardness" if that's what you are using instead. Dump the "Hardness", its only purpose is to mash your head!

AMS? Acidic Murphy's Solution. CRS (Carbonate Reducing Solution) made more sense? Well, name has changed now, and I don't think it'll be going back.

 

[aamcle]

I usualy just use Brewersfriend advanced water calculator. But if enough noise about RA comes along it gets confusing.

 

[doug293cz]

I usualy just use Brewersfriend advanced water calculator. But if enough noise about RA comes along it gets confusing.

Just ignore anything about RA.

Brew on

 

[Peebee]

Guess I should post this as I was singing the praises for that Hanna Alkalinity Cheaker.

Eighty quid well spent? I began to get warning when I attempted to "cross-reference" the results. 16 ppm (as CaCO3) the Hanna was giving me (24 hours to let chlorine dissipate ... colorimeters are very touchy about bleaching due to chlorine). I repeated the test with a Salifert mini-titration kit. 8x the sample (indicator too) to get some sensitivity as I have very low Alkalinity, and divide result by 8 because of sample size ... 7 ppm as CaCO3. That's twice I've had that magnitude difference in the results. I was dismissing the accuracy of the mini-titration kits, but it wasn't me doing the titrations. My partner, a lifelong Analytical Chemist (now retired) took over having taken pity on my attempts with shaking hands (She sneered a bit about the 1ml syringe not a burette). And! Two professional analysis (one only four months ago) both returned 8 ppm as CaCO3.

Conclusion: It's cost me eighty quid to learn those Hanna Checkers are unreliable (at the difficult "low alkalinity" levels that is). Salifert kits are a pain to get results, but seems they are much better.

 

[Peebee]

While I'm on this subject ...

I'm attempting to use a spreadsheet to dabble with Alkalinity at the "low" end of the scale (as can be deducted from that last post ... 7 ppm as CaCO3!). Shouldn't use old-fashioned "as CaCO3", it's "0.14mEq/l". I unashamedly want to attract @Silver_Is_Money into this and "mEq/l" is a honey-trap!

With such low Alkalinity the Water Company use Lime to prevent acidity rotting the pipes. This bumps the Alkalinity up to a reported 20ppm as CaCO3 (the water company is very old fashioned!). But by the time it reaches my tap it's down to 7ppm (0.14mEq/l) ... I understand it as the Lime being consumed in picking up the pH (to about 7.5ish), and the Alkalinity decreases with the consumed Lime. But that's as far as my "understanding" takes me ...

How can I account for the lower Alkalinity this suggests? Everything "Alkalinity" is worked out "as Bicarbonate", but if I reduce "Bicarbonate" I must reduce some "conservation-cation" to keep in balance? The obvious one is Calcium as the Lime added it, but titrations at my tap doesn't suggest the Calcium reduces at all.

BTW: I understand a little bit about water chemistry and related carbonate chemistry, but the bit I understand best of all is ... it's flippin' confusing!

Might attract some attention from @mabrungard with this one too? I reckon he owes me one for all the standing up for him on my side of the Atlantic (I never utterly understand the historic bun fights that go on 'tween Martin and some UK brewers).

 

[Silver_Is_Money]

@Peebee, I'm not sure at all as to what is being asked here. Low Alkalinity is accounted for and countered in exactly the same way as for high alkalinity. mEq's are mEq's, and all of chemistry as regards molecular level interaction is resolved via Eq's or mEq's. You want your mash plus your sparge water brought to the range of about 5.5 pH for either case.

If your water has 0.14 mEq/L of Anions it assuredly has 0.14 mEq/L of Cations as well, just as you have mentioned. There is nothing inherently confusing (or old fashioned) in equating this Alkalinity to CaCO3 unless perhaps for the case of the waters Cations being devoid of generally predominating Ca++ and/or Mg++, which would potentially very minutely impact mash pH computation methodology, but not sparge water adjustment computation methodology. Ca++ and Mg++ ions interact with malt phosphates whereby to liberate some small (albeit well less than commonly presumed, as per the research of Barth and Zaman, which reveals serious flaws in the much earlier work of Kolbach that so many are unwilling to let go of) of H+ ions. At the tap water level there is no malt phosphate because there is no malt in your tap water (unless your tap dispenses wort). Thus Ca++ and MG++ would not reveal themselves at the tap water level to be pH influencers, just as your research indicates.

But software accounts for such factors. If the above does not satisfy your query, then what are you asking?

 

[Silver_Is_Money]

For the benefit of the OP, residual alkalinity is merely an artifact (artificial construct) of the Barth and Zaman debunked Kolbach research dating to the 1930's. The kludge of Residual Alkalinity as a means to mash pH adjustment compensation must be abandoned whereby to achieve overall better results.

 

[Peebee]

@Silver_Is_Money: Thanks for the quick reply, sorry my reply is tardy, but despite what you said "I'm not sure at all as to what is being asked here" you managed to give me loads to think about (and hence I needed the extra time to reply).

Ha! But I did manage to snag your attention! I don't really know if that was down to the mention of "mEq/l" or not. I will say I'm sold on mEq/l, everything "as CaCO3" should be ... but isn't, it's only half-a-job. Minus ten for trying to defend "as CaCO3" because it is most certainly inherently confusing (you just have to look about these forums) and "old fashioned".

"mEq/l" (can you call them "Mekkles"?) are blindingly simple, and you can take credit for introducing me to them! Outlandish numbers, but dead simple maths, and an unfortunate "spiky" unit (mEq/l) but I wouldn't be able to try this current project without them.

"CaCO3" is actually something (Calcium Carbonate) but has really simple numbers (100, 50, 2/5, etc) great for pen-and-paper work. But I have a project using "Sodium" measured as "CaCO3" which is perfectly legitimate, and I only do it because I know it confuses the hell out of some folk.

I'm hi-jacking @aamcle's thread for this, but I think he was done with it. And he's a Brit too and well used to my bad habit (hijacking threads) so he might forgive me.


I'll try to better explain what I want help with. It'll take me a while to sort. Meanwhile ... it has something to do with this:

Total Alkalinity = ∑conservation-cations - ∑conservation-anions

And it may only an issue for minorities like me (have very low total dissolved solids, and therefore alkalinity, in their water). Hence, I'm not finding much already done with it?

 

[Silver_Is_Money]

Remember that to remove all Alkalinity (as CaCO3) requires a pH at right near 4, and that pH 5.4ish requires only ~90% removal.

 

[Peebee]

Remember that to remove all Alkalinity ...

Yep, I do, but this is purely a number game with the water as it comes from the tap (supply company's analysis) before mucking about with "additions".

Some background (sister forum):

https://www.thehomebrewforum.co.uk/threads/befuddled-by-the-defuddler.104595/post-1274010

The link is concerned about my kitchen laboratory attempts; the thread goes on about it more widely. The spreadsheet in my posts is very incomplete and barely touches the stuff I'm asking from you.

At which point @aamcle (if he's still following his thread) thinks: "Oh no, the ****** Def****** ... I come to this forum to escape from it"


I'll get back to describing what I'm after ... coming soon!

 

[Peebee]

This possibly doesn't apply throughout a vast continental landmass hike the USA, but the UK is a poky island on the very edge of the Eurasia continental land mass. Nowhere is more than 75 miles from the sea. Most drinking water is surface run-off with nothing surprising dissolved in it (doesn't get the chance). So virtually all dissolved solid is the "famous five" (Ca++, Mg++, Na+, Cl- and SO4--) plus HCO3- (equivalent) responsible for virtually all the Alkalinity plus some "artifacts" (never seen it explained in the way you ... @Silver_Is_Money ... put it, but it fits ... "human interference"?... logged in head for future use! ... in this case; pollution) of nitrate and phosphate. The rest, in parts-per-billion, can be ignored?

Hey! I hadn't realised until checking over this explanation: Phosphate belongs on the Alkalinity side of the equation, not the "conservation ions" side (Wikipedia). ... Flippin' Heck! That makes a difference! But I might be doing things wrong with Phosphate ("converting", virtually, the reported 0.92mg/l phosphorus to "phosphate" before adding things up). Still, I'm only calculating 25.01mg/l as Bicarbonate instead of the reported 25.42mg/l and all these reported figures are averages or means so together don't represent a "point-in-time" anyway. All the same, I should be proud of that calculated figure ... instead, I'm suspicious of it!

No need to check the following figures in detail, they are only working up to my question.

So, for my water: Ca=0.8708mEq/l, Mg=0.5159mEq/L, Na=0.3054mEq/l, Cl=0.3478mEq/L, SO4=0.8930mEq/l, with "artifacts" at NO3=0.0414mEq/l and PO4=0.0892mEq/l ... the phosphate is ignored as it is being included in the reported/tested Alkalinity anyway; therefore... (conservation-cations) 1.6921-1.2822 (conservation-anions, incl. NO3) = Alkalinity (in mEq/l) and therefore... =0.4099mEq/l therefore... =61.0168x0.4099 =25.01mg/l as HCO3

Cor! The numbers look long and scary, but it's a doddle this "mEq/l" stuff! "61.0168" is the magic number for recreating mg/l as HCO3 from mEq/l (actually the atomic weight of bicarbonate as the valency is one ... atomic-wt/valency).

NOW the crunch question! A titration (or two!) of my tap water returns Alkalinity as 0.14mEq/l. Somewhat short of the 0.41mEq/l calculated above. But to be expected? The acid moorland water will have consumed some of that "dosed" Lime on its way to my tap. Resulting in the "Alkalinity" dropping. Which it certainly appears to do. 0.14mEq/l is 61.0168 x 0.14 =8.5mg/l as HCO3. But you can't just remove anions without removing cations, or it's electrically imbalanced. So, what goes? Calcium doesn't seem to budge in concentration (from titration). What else?

Phew. That was exhausting

 

[Silver_Is_Money]

@Peebee. perhaps you're not really asking a question that involves Cation and Anion balance, but what you're really asking is why your kits (or someone's kits) titration derived Cation and Anion values don't resolve to perfectly harmonious balance. That's a kit problem. Kit resolution and accuracy is generally terrible. Here in the USA we mostly use Ward Labs, and even their methods can only get you somewhat close to honest Cation/Anion mEq/L balance, but the reality is that there is such balance. I look at this imbalance first when observing Ward Labs values, and I then shake my head at the people who consider them gospel as opposed to ballpark.

 

[Peebee]

That's okay. I've already dismissed the "Hanna" Alkalinity Checker ... Eighty quid should have instilled some expectation of "perfectly harmonious balance" in me. But I'm a natural sceptic, so it's done away with. The mini-titration kits (Salifert) should be mis-trusted 'cos they are well out-of-date, but are returning results not dis-similar to professional test I've had done (one only 4 months ago). And the exact result isn't my aim. I want a spreadsheet to return fairly reliable estimates of tap water analysis for anyone who wants it (but mainly the badly supported low alkalinity water, "soft water" if you must, users).

I've seen it lots ... brewers with water reports that show alkalinities below 60-70mg/l as CaCO3, actually experiencing much lower alkalinity at their taps - like my example of 25ppm as Bicarbonate reported, about 8ppm tested.

So, if I put something out that makes no attempt to balance the output, I expect it to be ridiculed. The formula I wish to use [ Total Alkalinity = ∑conservation-cations - ∑conservation-anions ] has to balance because it works by arranging the balance (virtually). But if the Alkalinity is falling, which must be the case, what is balancing it? And where's it going?

 

[Silver_Is_Money]

@Peebee, you might consider adding in a simple 'cheat' multiplicative factor which force balances the Cations and Anions.

 

[Silver_Is_Money]

If it's any consolation, human taste buds are notoriously terrible judges of ingredient changes. For example, when seasoning foods with herbs and spices it may take on the order of a 25%-30% change in spice levels before anyone begins to notice. And this is why grandma doesn't measure. The same is likely true for beers at many levels, and it's a likely contributor to why Brulosophy so often ends up concluding that there is no statistically significant difference. That people literally slave over hitting 'so-called' profiles dead-on is almost laughable when this is taken into consideration.

 

[Peebee]

@Peebee, you might consider adding in a simple 'cheat' multiplicative factor which force balances the Cations and Anions.

Can't. I'm already "cheating" trying to use one of those formulas that adds everything up, and whatever you find is missing is what you're looking for! It always balances because without it you haven't got any sort of answer. I reckon that's probably cheating?

As for chasing the impossible (I think that's you're getting at in the second post?) I have this philosophy: If people are wasting time trying to attain impossible (or ineffective) goals, I'll help them if I can, using one of my barmy spreadsheets or the like, so they can start wasting time on beer enhancing methods that I might benefit from!

And it is a bit of a game: I like the challenge of coming up with something that works, even if no-one uses them and carry on with the daft methods, etc., they were using.


For example: That SG project that you'd triggered in me ages ago. How many brewers do you think I encouraged to give up with their hopeless hydrometers? Not many, I reckon.

It's always annoying failing which is what seems to be happening with this water project.

 

[bobtheUKbrewer2]

Peebee - this is going right over my head so simple question what should I do with this water to make a 4% pale bitter, hardness as CaCO3 228 Ca 80 - SO4 107 - Cl 65 - Mg 9 - Na 39
thanks

 

[Peebee]

Peebee - this is going right over my head so simple question what should I do with this water to make a 4% pale bitter, hardness as CaCO3 228 Ca 80 - SO4 107 - Cl 65 - Mg 9 - Na 39
thanks

Ah! It may well be an over-complicated because I've been discussing stuff I'm trying to package into a simplistic tool (i.e. the head-ache inducing stuff I don't really want people to see).

And that stuff is so good at creating blinding headaches you've missed one of the spreadsheets important features ... it doesn't suggest what beer to make! It's a preprocessor to cleanup water reports of all the junk before you chuck it through a water calculator. Like that "hardness as CaCO3 228" which you don't need to know. It has nothing useful, for beer making, to offer. But it can mess your head up if you let it.

But, as I've spent the best part of the afternoon on the spreadsheet, incorporating wisdom from @Silver_Is_Money, I'll run that water profile you've given me through it (it's not fully functional, but it'll come up with something):

That's it! Not much to do 'cos you had all the figures anyway. Except you didn't need that "hardness" twaddle and you've got "bicarbonate" instead (I never used the "Hardness" figure, its useless here) ... which is covering your "Alkalinity". "Bicarbonate" is really a "equivalent", just not as silly as that "CaCO3" twaddle. It all balances, exactly, because it has no choice (it's calculated). Elsewhere the spreadsheet tranlates "Bicarbonate" into other ways of putting Alkalinity:

I could say "now go stick that lot in a water profile calculator", except for a "pale bitter" it looks pretty good as it is. Alkalinity a bit high, Sodium a tiny bit high, perhaps? Blah, blah, blah.

The obvious response this demo will create is "so what's it done?". What it's done is exactly what all those brewing water calculators should be doing ...

... but don't!

 

[Silver_Is_Money]

@Peebee, can you use this simple formula within your spreadsheet somewhere? I never did much with it after uncovering it somewhere across the vastness of the internet. And now that I've become a Type 2 Diabetic who refuses to accept insulin shots and thereby controls blood sugar only via diet (a diet devoid of sugars and carbs), I no longer drink beer, and thus I no longer make beer. With this being the reason why I don't post much to beer forums anymore... Edit: Although I've never met him, I count @Peebee as a friend, and that's why I responded to his beckoning call.

For any water of pH <= 8.4:
Water's Target pH = 6.40 + log(mol fraction of HCO3- to H2CO3)

As an example, lets determine how much of any level of extant HCO3- (as a fraction/percentage) must be removed whereby to achieve a water pH of 5.6?
5.60 = 6.40 + log(mol fraction of HCO3- to H2CO3)
-0.80 = log(HCO3- ÷ H2CO3)
10^-0.80 = HCO3- ÷ H2CO3
HCO3-/H2CO3 = 0.1585
(1 - 0.1585) * 100 = 84.15% HCO3- removal required

Answer: For any water with an initial pH of less than or equal to 8.4, regardless of its mg/L (~ppm) of HCO3-, we must remove 84.15% of the initial quantity of HCO3- present whereby to reduce this waters pH to 5.6.

As another example, how much HCO3- have we removed if we acidify an Alkaline water of pH 8.4 or less and we wind up with our pH meter reading 4.00 pH?

4.00 = 6.40 + log(mol fraction of HCO3- to H2CO3)
-2.40 = log(HCO3- ÷ H2CO3)
10^-2.40 = HCO3- ÷ H2CO3
HCO3-/H2CO3 = 0.00398107
(1 - 0.00398107) * 100 = 99.60% of the initial HCO3- ion present within our water has been removed

 

[Silver_Is_Money]

It's often claimed that 90% of initial HCO3- must be removed whereby to bring a waters pH to (the so very often targeted) 5.4 pH. Let's now find out why this is a valid claim:

5.40 = 6.40 + log(mol fraction of HCO3- to H2CO3)
-1 = log(HCO3- ÷ H2CO3)
10^-1 = HCO3- ÷ H2CO3
10^-1 = 0.10
0.10 * 100 = 10% (I.E, 10% of initial HCO3- remains when water has been acidified to pH 5.4)

Note: You can substitute Alkalinity as CaCO3 for HCO3- whereby to determine the same for Alkalinity instead of HCO3-.

 

[Silver_Is_Money]

At pH 6.4 the mol fraction of HCO3- equals the mol fraction of H2CO3. That's where the 6.4 factor in the simple equation is derived. Various of published charts seem to drift this equilibrium point and you may see it placed as low as about pH 6.2 on some carbonate species charts. I think 6.4 works best. YMMV

 

[bobtheUKbrewer2]

peebee thanks I think. brewing tomorrow adding 11 ml of CRS and 10 gm of AMS, hoping it will be drinkable........... (half campden tablet before the CRS)