Is my bicarbonate really this high??

[Brew_Meister_General]

My Local Water Report in London: (doesn't specify Ca/Mg)

Calcium carbonate: 264 ppm

Degrees German(DH): 15
Degrees Clarke: 19
Degrees French: 26

According to Bru'N my 'German degree Carbonate Hardness' (?)
= 268 ppm Alkalinity as CaCO3
= 327 ppm HCO3

327 ppm of bicarbonate seems awfully high! Have I done this correctly?

I imagine my water is very alkaline then, although my water pH is still 7.4

 

[z-bob]

My Local Water Report in London:
Calcium carbonate: 264 ppm
Degrees German(DH): 15
Degrees Clarke: 19
Degrees French: 26

According to Bru'N water my 15 'German degree Carbonate Hardness' (?)
= 268 ppm Alkalinity as CaCO3
= 327 ppm HCO3

327 ppm of bicarbonate seems awfully high! Have I done this correct?
I take it my water is very alkaline, although my water pH is 7.4

I'm looking at my local water report right now, in Rochester, MN. Alkalinity is 260 ppm, which 317 bicarbonate. Not quite as high as yours, but enough that it's tough to deal with.

 

[Brew_Meister_General]

I'm looking at my local water report right now, in Rochester, MN. Alkalinity is 260 ppm, which 317 bicarbonate. Not quite as high as yours, but enough that it's tough to deal with.

Does it state your Total Hardness at CaCO3 or Degrees German/American?

 

[Singletrack]

No need to imagine your alkalinity. It is 268 (by your calcs), and yes that is high. Mine is 241, and I blend RO water with tap water and then add a small amount of lactic acid. RO is your friend.

 

[z-bob]

I've been playing with the water calculator at brewersfriend.com About the only way to fix my water is to add gypsum and hydrochloric acid. It doesn't really require much (like 5 grams of each for 6 gallons), but it takes both.

Or I guess you could add enough slaked lime to convert the bicarbonate to carbonate and let it settle for a few days. Decant the soft high pH water off and use it. Some day I'll try that; do 15 or 20 gallons at a time and use if for the coffee maker, etc. (if any water experts are reading this, like AJ, would that also precipitate out the iron?)

 

[ajdelange]

If you aerate the water first (in order to oxidize the 'clearwater' Fe(II) to Fe(III) ) then Fe2(OH3) will precipitate but to get it all you will need to filter. Greg Noonan recommended clean play sand in a bucket with small holes as it can, at the completion of treatment, be backwashed,

 

[Brew_Meister_General]

I have a carbon filter which removes 'up to 70% of calcium carbonate' so I can use that to lower my bicarbonate, the downside being that it will also reduce my calcium which stands at 74 ppm (35% each?).

My current plan would be to use brewing salts and acid to lower the pH of my mash and then filter all of my sparge water to reduce its alkalinity whilst retaining an overall calcium level of 72-82 ppm.

I prefer brewing darker beers anyway so it shouldn't be a problem.

 

[D-Train]

Those carbon filters use ion exchange and add phosphate I believe. Test it with an aquarium test kit and I think you'll find that they lose their charge rather quickly and the process becomes unreliable not to mention rather slow.

Check out lime treatment as mentioned above. My carbonate hardness is 14 german dH and I can knock it down to 3 with the lime treatment.

 

[ajdelange]

No carbon filter that I am aware of removes calcium carbonate nor for that matter any of the minerals of concern. A water softener, commonly found, uses ion exchange to replace calcium with sodium and may reduce calcium hardness from 100 ppm as calcium carbonate to 30 ppm as calcium carbonate but most are much more effective than that reducing 100 ppm to 1 or 2 and none of them remove any carbonate or bicarbonate.

There are ion exchangers which do remove cations and these are found in the outfits lots of brewers who also keep reef aquariums use to produce RO/DI (i.e. RO followed by the ion exchanger this is done in order to prevent rapid exhaustion of the ion exchangers).

 

[D-Train]

AJ, that's true about a plain carbon filter, but my brita pitcher for drinking water does have some sort of ion exchange resin. I have tested water at 15 and 14 GH/KH, ran it through the brita filter, and then tested it at 6 and 7 GH/KH. This is with a brand new filter and I have no doubt that it depletes quickly over time. That and the painfully slow process make it unsuitable for brewing for me, but it does remove hardness and carbonate. I think it replaces with a lot of phosphate but I admittedly don't know the chemistry involved and whether that's correct or even possible.

 

[ajdelange]

Yes, Brita pitchers do contain ion exchange resins which substitute H+ for cations and OH- for anions. Thus 1 molecule of ionized CaSO4 is replaced by 2 molecules of water. And it is also true that the ion exchange capacity is very limited. I don't think any phosphate is added but do believe that a minute amount of silver ion is (for microbiological stability). Brita pitchers are not very practical as a source for brewing liquor.

 

[Brew_Meister_General]

AJ, that's true about a plain carbon filter, but my brita pitcher for drinking water does have some sort of ion exchange resin. I have tested water at 15 and 14 GH/KH, ran it through the brita filter, and then tested it at 6 and 7 GH/KH. This is with a brand new filter and I have no doubt that it depletes quickly over time. That and the painfully slow process make it unsuitable for brewing for me, but it does remove hardness and carbonate. I think it replaces with a lot of phosphate but I admittedly don't know the chemistry involved and whether that's correct or even possible.

When I messaged Aqua Optima they specified that it uses a 'weak acid cation exchange resin' whatever that is, replacing the ions of copper, lead and aluminium with hydrogen.

I just test it using my pH meter as its effective at lowering the pH from 7.4 to 6.0 if new (or 6.3 if old) so all I really need to do is filter the sparge water until it gets down to a suitable pH, like 6.0 I imagine.

 

[Brew_Meister_General]

1 molecule of ionized CaSO4 is replaced by 2 molecules of water.

So what implication would this have, that the filter extracts sulphate as well as calcium?

And it is also true that the ion exchange capacity is very limited.

Limited as in that they only filter a small percentage of temporary metals?

 

[ajdelange]

When I messaged Aqua Optima they specified that it uses a 'weak acid cation exchange resin' whatever that is,

It is a resin with loosely bound hydrogen ions on some part of the molecule. We could write it as RH+ with H+ representing the hydrogen ion and R the rest of the resin molecule.

...replacing the ions of copper, lead and aluminium with hydrogen.

The reaction with a metal cation would then be, for example

Al+++ + 3RH+ ---> R3Al+++ + 3H+

in which the hydrogen ion is released and the aluminum ion attached to the resin in its place.

I just test it using my pH meter as its effective at lowering the pH from 7.4 to 6.0 if new (or 6.3 if old)

As the pH goes down it seems that this device does not contain anion exchange resins. I haven't experimented with Brita pitchers in years but when I did cations were replaced too (basic exchange resin) but with hyroxyl ions so that acid base balance was retained.

Ca(HCO3)2 + 2RH+ + R(OH)- ---> R2Ca++ + 2RHCO3- + 2H20

...so all I really need to do is filter the sparge water until it gets down to a suitable pH, like 6.0 I imagine.

There is more to it than that. pH 6 insures that phenol extraction from husks is not likely but if the water still contains appreciable alkalinity with respect to desired kettle pH, that desired pH will not be reached. So you really need to know what this pitcher does. Does it also do anion exchange? Does it also reduce hardness (replace calcium, magnesium, sodium etc.)?

 

[ajdelange]

So what implication would this have, that the filter extracts sulphate as well as calcium?

Yes, if it contains an anion exchange resin.

Limited as in that they only filter a small percentage of temporary metals?[/QUOTE]

No, though that is at issue as well. In these pitchers the water isn't in contact with the resin for very long and it may take a couple of passes to reduce the mineral content to low levels.

What I was referring to is that the pitchers are small and don't contain much resin. In the example reaction with aluminum (as we spell it this side of the pond):

Al+++ + 3RH+ --> R3AL+++ + 3H+

3 resin sites are used to trap 1 aluminum ion. There are a finite number of resin sites and thus a finite amount of cations can be removed. These devices are meant to process small volumes or water for drinking - not the large volumes intended for brewing. Given that your water is quite hard I would expect a pitcher cartridge to be exhausted quite quickly.

 

[Brew_Meister_General]

So you really need to know what this pitcher does. Does it also do anion exchange? Does it also reduce hardness (replace calcium, magnesium, sodium etc.)?

I'll have to make a request for some sort of report that details these processes but in regards to what you said about pH I'll assume for now that it doesn't do anion exchange.

It doesn't filter any of the other minerals, i.e. sodium, sulphate, chloride, magnesium, just calcium carbonate (264 ppm = 74 calcium / 254 bicarbonate) which I can only assume transposes as removing an equal percent of calcium and bicarbonate from the water.

So before embarking on my long and winding journey through water chemistry, what would you do to treat hard water?

 

[z-bob]

The easiest way to treat water (but it uses a lot of energy) is to boil it, let it cool, and decant the decarbonated water off the sediment. You might have to add gypsum or slaked lime or calcium chloride if the water doesn't naturally have enough calcium to balance out all the carbonate.

I don't know how long it takes for the chalk to settle out.

I'm seriously looking at using hydrochloric acid to remove the bicarbonate. Then I'll have to add gypsum to the mash to supply calcium and to balance out all that added chloride with sulfate.

I'm not sure how you know when you've added enough HCl... You can calculate it, but that depends on having an *accurate* water analysis. (I don't know if the water report from the city is accurate, or if it just reflects the worst case sample from all their wells.) I'm guessing the pH stays pretty steady at about 7.5 until you've neutralized all the bicarbonate, then it starts to drop rapidly. You'd want to catch it right at the inflection point.

 

[Brew_Meister_General]

The easiest way to treat water (but it uses a lot of energy) is to boil it, let it cool, and decant the decarbonated water off the sediment. You might have to add gypsum or slaked lime or calcium chloride if the water doesn't naturally have enough calcium to balance out all the carbonate.

Would that remove all mineral content then, i.e. would it become distilled water?

 

[douglasbarbin]

Would that remove all mineral content then, i.e. would it become distilled water?

No, but I imagine it would be a lot closer to distilled water than what you started with. In this case, the water is still in contact with the sediment, and some of it is inevitably going to end up back in solution. Distillation relies on separating the water into vapor, at which point the water vapor travels to a separate chamber where it is then condensed and the condensate is collected.

 

[mabrungard]

Would that remove all mineral content then, i.e. would it become distilled water?

The primary mineral content that boiling can reduce is calcium and bicarbonate via precipitation as chalk. The other ionic content is typically too soluble to precipitate.

To distill, the water has to come off as steam and be recondensed in another vessel.

 

[Brew_Meister_General]

The primary mineral content that boiling can reduce is calcium and bicarbonate via precipitation as chalk. The other ionic content is typically too soluble to precipitate.

To distill, the water has to come off as steam and be recondensed in another vessel.

Okay last question, would you recommend just using phosphoric acid to reduce the alkalinity of my sparge water? What level of bicarbonate should I aim for (0 ppm)?

 

[mabrungard]

Okay last question, would you recommend just using phosphoric acid to reduce the alkalinity of my sparge water? What level of bicarbonate should I aim for (0 ppm)?

Yes, at least partially. Using a combination of acids could be a benefit with the high alkalinity you report. As you already know, you also have access to CRS or AMS and those hydrochloric/sulfuric acid mixtures may be a step in the right direction. My problem with those products is that they tend to add too much chloride in some cases. Including phosphoric and lactic in your repertoire could help avoid overdosing on any one of the anions that the acidification will produce.

The bicarbonate level varies. Zero is not always the target. In general, sparging water should have less than 30 ppm bicarb. However, mashing water can have a requirement for higher or lower bicarb content depending on the acidity of the grist. Functionally, the bicarb content can actually be less than zero (this just means that there are excess H+ protons in the water) when mashing pale grists.

 

[ajdelange]

Okay last question, would you recommend just using phosphoric acid to reduce the alkalinity of my sparge water? What level of bicarbonate should I aim for (0 ppm)?

That would require a pH much lower than what we can tolerate in brewing. But no matter as we don't really care what the bicarbonate level is instead aiming for 0 alkalinity with respect to desired mash pH in the case of mash water and with respect to desired kettle pH in the case of sparge water. We hit these targets by adding enough acid (of whatever type or types we settle on) to bring the pH of the water (mash or sparge) to the desired pH (mash or kettle). There will still be some bicarbonate in the water but not much and it will be of no concern to you.

As to the choice of acid: that is really up to you. The essential thing you must remember is that every bicarbonate ion removed with acid is replaced by the equivalent amount of the acid anion. Examples:

2 HCO3- + 2 HCl --> 2 H2O + 2 CO2 + 2 Cl-
2 HCO3- + H2SO4 ---> 2 H2O + 2 CO2 + SO4--

Control of chloride and sulfate ion content allow you to adjust body, sweetness, roundness and hops bitterness perception. Phosphate is very flavor neutral. Lactate has quite a prominent flavor. You will just have to experiment until you find what you like best.

 

[ajdelange]

Functionally, the bicarb content can actually be less than zero

As we have discussed many times before the bicarbonate cannot be less than 0. Even water at pH 0 with total carbo content of 1 mmol (it would have to be under pressure) would contain 0.01 µmol bicarbonate. The alkalinity can, on the other hand, be negative (for this example it is -1069.59 mEq/L RE pH 4.5) and that is why chemists speak in terms of it. By stating that the bicarbonate content can be 'functionally' less than 0 (you would say that it is -65245 mg/L) you can only hope to add more confusion to those trying to understand a subject which is already confusing enough as it is to most. The situation is not helped by American insistence on adherence to expressing alkalinity 'as CaCO3' (and temperature in °F, mass in lbs etc.) but even here we seem to be getting away from 'as CaCO3' and moving to the much more sensible mval or mEq. Why do you want to make things harder for people?

(this just means that there are excess H+ protons in the water)

So why not just say that there are 1069 mEq/L excess protons (wrt the reference pH) rather than saying there are -65245 mg/L bicarbonate?