In-Line Water Treatment for Chloramines

So today is water day ... in my effort to get back into brewing I've spent a day here on one subject, there on another. Today is water and I've been reading pretty much since 6 AM (8 hours now).

Apparently the aliens landed and convinced water departments to use chloramines instead of chlorine somewhere in the past 10 years or so. I missed that. Since my time machine is not working, I guess I need to step into the 21st century and deal with it like a man.

I've made a couple batches of mead here lately just to whet my appetite, and I'm a no-boil guy so I use Campden. I gather this was a bit of serendipity since Campden helps to allow the chloramine to off-gas. All well and good there. I do however plan to get back into AG brewing again so some planning is in order. My original intent was an RO/DI setup for my water, to which I would reintroduce what I wanted. I gather that this is only marginally effective for the reduction of chloramine?

So how can a guy reduce chloramine in-line, in order that the RO/DI setup can be used? I suppose I could collect water first, then add the Campden and allow it to gas off, but I'd sure like to be able to turn on a valve and have water I can use. Am I missing something or is this just no longer possible? Is the only way to do it a really big-a** carbon block?

Choramine and chlorine are poisonous to RO membranes and, therefore, every RO system contains a carbon filter in line before the membrane to remove them. Theoretically, let me repeat that, theoretically, the carbon filter will never become exhausted if the only source of chlorine is chloramine. If any chlorine is present or if the real world doesn't match theory then it will eventually become exhausted and will need to be replaced. Any hint of chlorine odor in the permeate or concentrate would be an indicator that the filter should be replaced.

AJ is correct. In my activated carbon course in grad school, we learned that chlorine and chloramine are not removed from water by adsorption. Adsorption is the way most contaminants are removed from water when using activated carbon. In the case of chlorine and chloramine, they react with the carbon and result in chloride. So with the large mass of carbon in a typical filter, it should last a long time. Unfortunately, that is not what happens in practice. You can generally get a few thousand gallons of water through the carbon before its exhausted. Be ready with a new filter. Checking the filter discharge with a Total Chlorine test kit for pools is a good idea. Do not rely on your sense of smell when dealing with chloramine since it is not very volatile and can be difficult for some people to detect.

Now that's just ironic since in the 8 hours I spent reading this morning, the two of you represented a large percentage of what was not discarded as crap and superstition. Thanks for the replies.

That's great news then - the takeaway from my reading earlier was that carbon only did a so-so job. May I expect then that the flow rates typically achieved by counter-top RO/DI units is suitable for the conversion to chlorides? I further suppose that a GAC unit would be indicated, possibly two in-line with a test tap between them would be safest for the membrane?

Last question about this I think ... the chloride anion should then be bound in the DI unit, correct?

This is all good news ... I envisioned some sort of water tank/airstone setup and Campden treatment, followed by having to pump the water through the RO/DI unit. That was not sounding so bueno.

It's not that carbon filters do a so-so job it's that slow flow rates are necessary as the reaction is slow. I think it's fair to assume that a manufacturer will put enough area in his filter that it will, at the flow rate at which it is desired to operate, effectively reduce the chloramine to a level safe for his membrane.

Is a second filter in series and before the RO unit a good idea? Sure if you like the belt and suspenders approach and especially if you want dechloraminated water for other purposes in the household. Obviously breakthrough would occur in this filter first while the unit's filter has plenty of remaining capacity.

The chloride ions aren't bound in the unit - they go out with the concentrate waste stream i.e. they don't cross the membrane (or most of them don't)/

Excellent, thanks for the confirmation, and reassuring me my OCD is still raging.

LBussy said:

Excellent, thanks for the confirmation, and reassuring me my OCD is still raging.

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Oh, if you're OCD, you've come to the right place.

(I think when AJ was talking about "belt and suspenders" he might have been referring to people like me!)

Well of course we know it's actually CDO then.

LBussy said:

Apparently the aliens landed and convinced water departments to use chloramines instead of chlorine somewhere in the past 10 years or so. I missed that. Since my time machine is not working, I guess I need to step into the 21st century and deal with it like a man.

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SOME water departments made that change. I didn't see in your OP where you stated that yours actually did change. Lots of folks see that and just assume their utility did. A quick phone call to them will verify.

Where I am, there are very few using chloramine.

The regs called for smaller and smaller plants as time progressed to implement chloramination so that almost any medium sized facility is now doing it. The exceptions are those facilities that disinfect by ozonation. The hardware is expensive so I don't know how prevalent that is.

Anyway, it is easy to determine if you are chloraminated. Just let a tumblerfull of water stand out overnight. If you can still smell chlorine in the morning (pour the water back and forth into another tumbler as you sniff) then it is likely that chloramine has been used. To be certain a chloramine test kit can be had for a few $.

Huff360 said:

SOME water departments made that change. I didn't see in your OP where you stated that yours actually did change. Lots of folks see that and just assume their utility did. A quick phone call to them will verify.

Where I am, there are very few using chloramine.

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Yes they have made that change.

ajdelange said:

The regs called for smaller and smaller plants as time progressed to implement chloramination so that almost any medium sized facility is now doing it. The exceptions are those facilities that disinfect by ozonation. The hardware is expensive so I don't know how prevalent that is.

Anyway, it is easy to determine if you are chloraminated. Just let a tumblerfull of water stand out overnight. If you can still smell chlorine in the morning (pour the water back and forth into another tumbler as you sniff) then it is likely that chloramine has been used. To be certain a chloramine test kit can be had for a few $.

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Gotcha. Not much of any size around here. They are all broken up into little municipal plants.

LBussy said:

Yes they have made that change.

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Good deal. Just checking.

ajdelange said:

The regs called for smaller and smaller plants as time progressed to implement chloramination so that almost any medium sized facility is now doing it. The exceptions are those facilities that disinfect by ozonation. The hardware is expensive so I don't know how prevalent that is.

Anyway, it is easy to determine if you are chloraminated. Just let a tumblerfull of water stand out overnight. If you can still smell chlorine in the morning (pour the water back and forth into another tumbler as you sniff) then it is likely that chloramine has been used. To be certain a chloramine test kit can be had for a few $.

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Ix nay! The regs call for utilities to eliminate Trihalomethane production in their water. For utilities that have little to no dissolved organic matter, they are not and will not be converting to chloramines. Chlorine is cheaper and more effective in kill power, so it is a lose-lose to switch to chloramine unless you have to.

Not sure what you mean by this. As of 2004 about a quarter of the utilities in the US were chloraminating in order to meet the DBP rule and that number was growing as at first only utilities serving more than X had to comply then utilities serving Y < X (or maybe I'm confusing that with the monitoring requirement). At any rate the number of plants using chloramination was growing but then some problems with chloramine were uncovered and some utilities began to switch to ozonation/UV treatment (at least that's what the local utility did) so perhaps the number of chloraminating operators has shrunk or stopped growing so fast. When I did my article on the subject it seemed there were new plants coming on line every day but that was some time ago.

How many utilities have 'little or no' dissolved organic matter?

Chlorine is a more effective disinfectant in the sense that it takes less CxT to get the same log kill but chloramine is more stable (so you have lots of T) in the system which is one advantage you have to grant to it. It was used for this reason even before the DBP rule came along.

Most groundwater supplies that are isolated from direct surface water intrusion typically have little dissolved organic matter and don't have any problems meeting the DBP requirements when using chlorine disinfection. My city is in that category.

Disinfectant stability only matters in systems that have excessive 'water age' in the system. With adequate water usage across the system or with the inclusion of a water main flushing program, the water age can be managed and the cheaper disinfectant can be used.

Due to its superior killing power, many utilities using chloramine do switch their disinfectant to chlorine during a short period (typically winter when the DOM content is low) to help eradicate microbes that might otherwise resist the chloramine.

mabrungard said:

Most groundwater supplies that are isolated from direct surface water intrusion typically have little dissolved organic matter and don't have any problems meeting the DBP requirements when using chlorine disinfection. My city is in that category.

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Mine isn't. In Virginia 25% of the population is served with chloraminated water. In Texas that goes up to 50% and, most important to the OP in MO the number is 44%. But there are some areas where there is very little chloramination such as Arkansas where it is virtually non existent. Overall for the US 22% of the population has chloraminated water but the number is growing. Between 2007 and 2010 the number of plants using it grew 37%. I thought everyone was switching to ozone.

mabrungard said:

Disinfectant stability only matters in systems that have excessive 'water age' in the system. With adequate water usage across the system or with the inclusion of a water main flushing program, the water age can be managed and the cheaper disinfectant can be used.

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There is a requirement for a disinfectant residual in the system. Chloramine's virtues in this regard are constantly cited as a major reason for its choice though meeting DBP rule is doubtless the main reason. All systems have points where flow is low and we can't be running around opening fire hydrants every week.

mabrungard said:

Due to its superior killing power, many utilities using chloramine do switch their disinfectant to chlorine during a short period (typically winter when the DOM content is low) to help eradicate microbes that might otherwise resist the chloramine.

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Around here (VA), as is typical, they start with chlorine going into the clearwells where the water stays long enough to get sufficient CxT and is then ammoniated as it goes into the mains giving them the best of both worlds (with the exception, of course, of the fact that some THMs get formed in the clearwells). Or at least that's how they used to do it. They were planning to switch to ozone. In DC, where the some of the mains are still wood, they do do the supechlorination thing in the spring.

Most of the Fort Worth area (Trinity River Water District) uses ozonation for primary disinfection, but it gets 3-4 ppm chloramine on the backend before it hits the distribution network. Further the Texas Council on Environmental Quality requires a .5 ppm residual at the faucet. I got all this from their test engineer.

It makes sense that no matter how pure the water is, it could get nasty when it hits the pipes. I don’t think that is unique to Texas.

All the conventional wisdom says that carbon filters are very slow to get chloramine. Yet everybody and their dog seems to be getting away with it. None of the homebrewers I know are using anything but carbon, typically a 5 micron hose filter. I have tasted chlorophenols and they are really hard to miss. What gives?

I have just recently started using potassium metabisulfite (.25g) and I can’t tell that it does anything.

OP, why wouldn't you just keep a bunch of 1/4 campden tablets handy and when you make about 5 gallons of water up, just crush, mix with water in a glass and add to the container before filling? It can't take more than a minute...

Homercidal said:

OP, why wouldn't you just keep a bunch of 1/4 campden tablets handy and when you make about 5 gallons of water up, just crush, mix with water in a glass and add to the container before filling? It can't take more than a minute...

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My name is not OP but I'll answer. :cross:

The desire is RO/DI water, the need to get there is no chloramine/chlorine to avoid damage to the RO membranes. I can remove the chloramine as you say, but then pumping it back through the RO/DI setup would be additional work/expense.

Gotcha. I didn't catch that chloramines were dangerous to RO filters. I read it as the carbon filter portion became ineffective after a short while.

So how much water could a person expect to get out before the RO filter is useless?

To kinda answer my own question - I pinged some of my old reef-keeping acquaintances and found the current go-to place for RO/DI units:

Up to 50GPD, @ $109.95, The Mighty Mite D.I.. Four stages including carbon, RO and a DI bed, sounds like a decent way to get DI water @ home (if you remember to start filling up early):



The place is called "Air, Water, & Ice" and has a pretty complete catalog. No financial interest, etc., etc..

Of course an inexpensive starting point is generally an expensive maintenance proposition. They have larger, more mainstream units starting @ $149. I just also found out they were local which is kinda nice.

Lee, that does look good. However, the carbon pre-filter is going to require a shorter replacement interval and you certainly don't need the DI component in brewing. My large-scale brewery clients tend to use nanofiltration, which is a coarse form of RO treatment. It actually lets more of the source water's ionic content through the membrane into the product water. However, it still reduces the ionic content to substantially lower levels while reducing water and energy usage. I bring this up to highlight that getting every last ion out of brewing water is not a good goal. If this system is going to also be used for aquarium usage, then never mind what I said

Going with a more common RO unit with 3 or 4 stages that uses the typical 10-inch filter cartridges may be a more economical unit in the long run.

LBussy said:

Air, Water, & Ice

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This is where I got my RO/DI from as well. They were good to deal with and shipped it out same day. I got the Hurricane Dual Home/Reef. Thought it was a good deal since it came with storage tank, permeate pump and TDS meter. I upgraded the tank to a 5 gallon one (fits under the utility sink) and had them also throw on a pressure gauge. I got a set of spare filters from them since they also seamed to be priced well. With my order they threw in a hand held TDS meter, which I thought was nice since I didn't know about it until I unpacked the box.

The tank is nice to have since we use the RO for the iron and dehumidifiers. We were buying gallons of distilled prior. I just wish I had room for a 10 gallon tank. That way I could of had a full volume of water on hand for a batch, without utilizing other storage containers.

I got an RO/DI since I plan on getting back into the saltwater aquarium hobby again. Otherwise I may have gotten just an RO unit.

mabrungard said:

My large-scale brewery clients tend to use nanofiltration [...] may be a more economical unit in the long run.

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That's a very rough paraphrase but please allow me the liberty because I do get what you say.

If I was a brewery your advice would be perfect. I don't brew every day, I don't have lab staff or at least people responsible for running samples to the lab, and pilot batches are pretty much too cumbersome for most home brewers. Kansas City water can switch day to day based on runoff, ambient temps, etc.; they mix between well and river water.

Because of those caveats, it is simpler for a homebrewer, or at least this homebrewer to start with as consistent a product as possible. A 50% reduction in hardness and then adding "stuff" back to this dilluted product may be a significant difference to my brewing when you compare that 50% in April and that same 50% in June. I know, I should brew more, but I digress ...

It would be nice to have some of those minerals and natural yeast nutrients in my water, but if I can't count on them being consistent then it is more of a liability than I am willing to accept. And of course it is important to remember that I am a homebrewer attempting to emulate a commercial offering in a lot of cases, not trying to establish my own brand. If the latter were the case I could design my batch around the water. Since I am looking to "be in Pilsen for a day" I need a way to get there.

As with many things, the "cheapest" solution may not be cost effective in the long run. As you say standard 10" filters are likely more serviceable and will be cheaper to purchase refills. I posted that one device as an example to someone else who may stumble across this thread, I personally hate "dangling threads" and wanted to be somewhat complete. However, my plans are for a different system from the same place:

I am looking towards the "The Typhoon III Extreme 150":

• 10-micron pre-filter
• GAC filter
• 1 micron carbon block
• 150 GPD membrane rated at 98% rejection of TDS
• Mixed-bed DI (anion and cation)
• RO only sample port
• D.I. water Bypass system ball valve & check valve
• ASOV: Valve is activated by water pressure and shuts water to system off
• Float valve - activates the ASOV.

It also comes with some "instrumentation":

• TDS alarm light, a "go/no-go" check
• Hand held digital TDS meter
• Dual probe dual reading digital in-line EC meter reads membrane and D.I. water TDS.
• Frame mounted psi gauge (0-100).

For $279.95 this is a pretty significant upgrade at what I think is an excellent price. I'm not going to pull the trigger today, but I think that's where I'm headed eventually.

mabrungard said:

I bring this up to highlight that getting every last ion out of brewing water is not a good goal. If this system is going to also be used for aquarium usage, then never mind what I said

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Why would one not want to start with RO/DI if they are adding the ions back in to get the profile they want? Is it simply just a cost factor? I would think best case is to start with RO/DI vice RO alone.

Everything has a price. The cost to take out more ions costs more in reject water and in energy to get the product water through the membrane. With a DI component, eventually you have to replace the cartridges. In addition, there is that minor cost of adding a little extra mineral to the water. For those bean counters at the Majors, those pennies per barrel that are saved, add up to dollars per day per brewery. Those concerns are not something we homebrewers or small craft brewers need to concern ourselves with.

Lee, you have a good point with a variable water supply. However, you overestimate the amount of ions that make it through a RO or Nano membrane. For RO, the typical ion percentage making through the membrane is around 5%. For Nano, its around 15%. Even with a large change in the source water quality, the product water will only change a few ppm. I don't typically worry about changes of that size in water.

By the way, that is a sweet system in that picture.

I replied in your other post with details on my system, but I would say that a 150 GPD system should work well for you. I brew 12 gallon batches, and I'm happy with my RO system.