Is campden stable in solution?

[Sadu]

Looking for a bit of advice from the chemistry folk here please.

I'm building a small automated brewery. I'd like to be able to remove chlorine from the water as the HLT gets filled but I don't have budget for water filters or RO. Also don't have enough available kettles to have the full water volume sit overnight, although that's another option I'm considering.

I was thinking, if I was to mix up a campden tablet into solution in advance and have my system automatically add that solution to the brewing water at the appropriate time, would that be a viable option?

Or would the chlorine-stripping properties of the campden be lost over time sitting in the solution? (I'm talking about a few hours or overnight here, not long term storage)

Thanks in advance

Edit: the reason I like the idea of a campden solution is that I need to do this anyway for adding the other water salts. So it would be campden tablet, CaCl2 and CaSO4 dissolved in solution, which would get auto-dropped into the HLT as it begins filling for the sparge.

 

[RPh_Guy]

Sulfite reacts with oxygen, so no, it's not stable with open air exposure.

Are charcoal water filters expensive?
https://www.amazon.com/Camco-TastePURE-Flexible-Protector-40043/dp/B0006IX87S/

 

[ajdelange]

As you can smell sulfur dioxide when near a bisulfite solution it is clear that SO2 is leaving it so it is unstable from that POV and, as it is commonly used as an oxygen scavenger, it is clear that it will take up oxygen from the air (or anything else) so it is unstable in that sense too. However solutions used to calibrate the 0 point on DO meters are usually metabite or bisulfite so it is clear that solutions of them are stable enough in a closed bottle for a pretty long time. Over night in a closed container you will be fine. And there is a simple test. If it smells of SO2 it is OK for chlorine/chloramine reduction.

Note that if it is only chlorine involved that standing overnight in the HLT will often be sufficient. Sparging with air when the water is hot should get rid of most chlorine. There are simple test kits and your nose is, again, a valuable instrument.

 

[Sadu]

Cool, thanks for the replies.

The other option I'm looking at is bringing the sparge water to a boil for 15mins during the mash. I'd need to mount an immersion chiller in the HLT to bring it back down to sparge temps again. Which is fine since I have a spare one.

On the other hand those charcoal filters seem cheaper than what I was expecting - for some reason I thought the water filters were in the hundreds of dollars range.

 

[ncbrewer]

You mention chlorine. Just checking: Is it chlorine or chloramine?

 

[Vale71]

I'm sorry, you're building an automated brewery but don't have $50 for a sediment and carbon block filter combo?

https://www.amazon.com/Sediment-Act...ated+carbon+block,aps,230&sr=1-32-spons&psc=1

These filters are very stable and will allow you to treat your water in real time on an as needed basis.

 

[Sadu]

You mention chlorine. Just checking: Is it chlorine or chloramine?

Chlorine.

I'm sorry, you're building an automated brewery but don't have $50 for a sediment and carbon block filter combo?

Yeah, I thought they were a lot more expensive than this so I didn't really look into that option. At $50 plus shipping this could well be the simplest way to go. How many gallons of water could one expect to get out of one cartridge before replacing?

 

[Vale71]

How many gallons of water could one expect to get out of one cartridge before replacing?

That strongly depends on your water quality. The more solids it has in suspension the faster the filters will clog.