Bromide in A/C System Cooling
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Delfin
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I think you mean Bromine, not Bromide. I haven't used it in a/c loops but have in irrigation systems when pumping water out of a pond. Kills the algae and doesn't hurt what is being irrigated. As I recall, we used an inline cannister that you would keep filled with the tablets. Seemed to work ok with fresh water, but if mixed with salt water I suspect you'll produce copious quantities of bromine gas, which will eat the heck out of any metal parts. When bromine is used in irrigation, all the fittings are plastic for that reason.
Doesn't sound like the best idea, but a pool expert can probably tell you what you need to know since bromine is used as a replacement for chlorine (right next to each other on the periodic table), which means they have similar reactions when exposed to salts.
JD
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Either Chlorine or Bromine from the swimming pool store work well in the A/C. Not all of the time but a couple of tablets in the seawater strainer let it set for an hour or two and start the A/C. It will clean dirt and Algae out with out any harm to your unit.
i just did the same to my Gen Set and the first time i fired it up the water came out all brown for about 5 seconds.
i just did the same to my Gen Set and the first time i fired it up the water came out all brown for about 5 seconds.
Delfin
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No question it will kill the algae. Also no question that it is eating up the metal in the system, although I have no idea how long it would take to irreparably damage the system.
From wikipedia by way of reference:
Being less reactive than chlorine but more reactive than iodine, bromine reacts vigorously with metals, especially in the presence of water, to give bromide salts. It is also reactive toward most organic compounds, especially upon illumination, conditions that favor the dissociation of the diatomic molecule into bromine radicals:
When the water has salt in it, the reaction is quite a bit more energetic. That's why mixing chlorine with sea water is a really good way to replicate a WW I gas attack.
Not too surprising that the exhaust water of your genset came out brown, since any rust would be eaten away by the gas you created. Along with part of the water jacket, of course.
The idea of using chlorine or bromine in an engine at high temperatures is even less appealing than using it in cold sea water. From the Process Chemical Corrosion manual:
Bromine
Susceptibility of materials of construction to attack by bromine is strongly dependent on the conditions of service including temperature, pressure and moisture content. Therefore, wherever possible materials selected for bromine duty should be tested under the actual conditions of use.
Storage vessels are commonly constructed of steel lined with lead, PVDF (and certain other fluoropolymers) or glass. If the bromine is 'dry' then Nickel or alloys such as Monel and Hastelloy can be used though all are susceptible to severe attack in the presence of wet bromine. Titanium is unsuitable for Bromine duty (wet or dry) and should be avoided.
Lead is used for lining steel storage vessels and less frequently for lining pipes but at high moisture contents and/or elevated temperatures the protective layer of lead bromide that forms on the surface of the metal is susceptible to degradation. Non-metallic linings including glass and certain fluorocarbon polymers, including PVDF and PTFE have replaced lead in most applications. Melt processed polymers such as PVDF, PFA and ETFE are preferred to PTFE due to its inherent porosity.
Few metals are suitable for use in contact with 'wet' bromine (moisture content in excess of 30mg/kg). Niobium, Tantalum and alloys of these two metals are suitable but high cost restricts their use (e.g. bursting discs and instrument components). Unless you genset has a Tantalum block, you might want to rethink that process.
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JD
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As in the twin engine or type of anchor discussions there are many views.
All I can speak from is my personal experience and that is for the last twelve years I have had boats in salt water. They have all have had A/C and I have used chlorine tabs in them for cleaning of the coils. I have seen no ill effects on the units. Chlorine is caustic and by no means do I condone leaving it in your unit every day all day long. But if the small amount it takes to clean out the Algae is going to effect a weld or solder joint I suspect that joint was about to fail soon anyway.
This subject has been discussed before and I'm sure it is in the archive if someone cares to look. Several folks on this list that are well respected for their opinions have used chlorine and have not had any problems. I'm sure that someone, someplace has done a flush and three days later had to replace an A/C compressor or other part and the failure was blamed on the chlorine.
As the saying goes "your mileage may vary"
All I can speak from is my personal experience and that is for the last twelve years I have had boats in salt water. They have all have had A/C and I have used chlorine tabs in them for cleaning of the coils. I have seen no ill effects on the units. Chlorine is caustic and by no means do I condone leaving it in your unit every day all day long. But if the small amount it takes to clean out the Algae is going to effect a weld or solder joint I suspect that joint was about to fail soon anyway.
This subject has been discussed before and I'm sure it is in the archive if someone cares to look. Several folks on this list that are well respected for their opinions have used chlorine and have not had any problems. I'm sure that someone, someplace has done a flush and three days later had to replace an A/C compressor or other part and the failure was blamed on the chlorine.
As the saying goes "your mileage may vary"
Delfin
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I have no doubt chlorine or bromine gas will kill algae, just like it killed people in WWI. The question is whether it also eats metal and that is just a matter of chemistry. It does. Does it matter? Apparently not to some, but it's not like saner alternatives don't exist. For example:
http://trac-online.com/pdf/TDS-Trac_Coil_Cleaner.pdf
To the OP's question, yes you can meter bromine into your a/c using bromine tablets. And yes, it will dissolve the metal in your system. Someone else may have other information, but I don't know of a way to meter an algaecide through an a/c loop that wouldn't be cost prohibitive, so just cleaning it out once every few months with a product designed for the purpose is probably the way to go.
Delfin
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Larry, if you look at the MSDS, you'll see that Barnacle Buster is diluted 85% phosphoric acid. That product will also clean out a/c loops and is less likely to attack welds where chlorine gas certainly will. The product I referenced is made by the same company that owns Barnacle Buster and doesn't use any acids.
JD
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The product in your link is great for cleaning the outside but we are talking the inside. It is cleaning dust dirt and grease not Algae.
The other product that Larry suggested is 65% Phosphoric Acid. I'm going with Cl. So far no one has died of Cl poison on my dock and there still enough metal to cool the boat and no leaks. So
I'm done here.
Delfin
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Quite right, I stand corrected on the use of the Coil Cleaner. But no, Barnacle Buster is about 10% phosphoric acid, not 65%. Phosphoric acid is what is used for solder flux so it doesn't cause issues with soldered joints. The issue is not whether you want to use chlorine gas, which is highly reactive to solder as your preferred way of cleaning an a/c system, but whether you want to represent that as a preferred practice to someone asking a question.The product in your link is great for cleaning the outside but we are talking the inside. It is cleaning dust dirt and grease not Algae.
The other product that Larry suggested is 65% Phosphoric Acid. I'm going with Cl. So far no one has died of Cl poison on my dock and there still enough metal to cool the boat and no leaks. So
Perhaps you might want to try methyl bromide the next time you want to clean out your lines. It's readily soluble in water and I can guarantee that nothing will be alive in your system after a good dose of that.
Delfin
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Probably not a bad idea.
RickB
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Delfin
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There is no dispute that bromine will kill critters. It also dissolves metals, which I guess if you have a tanker with a zebra mussel infestation is a lesser order problem. In an a/c unit in a pleasure boat without that problem, there may be other solutions that don't dissolve your system. But to each his own, and we will put you down in the camp recommending chlorine and bromine gas as an effective algaecide, which it most certainly is. But like I said, if you like chlorine gas, you'll love methyl bromide. That's the he-man solution.
RickB
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Which metals in your system do you believe will be dissolved? Got any citations to show that your belief is fact based?
Bromine treatment of non ferrous heat exchangers has been around a long long time and is very safe and effective. Show us where it is not. Bromine water treatment is not a "he-man" solution, it is a water treatment industry standard.
Methyl bromide is a fumigant gas and has about as much to do with water treatment as zinc phosphide has to do with anodes.
It is ignorance and mythology that has given bromine water treatment a bad name in the recreational boating world, not reality. Someone posted something on a website and repeating it makes the poster sound smart ... at least to folks who don't know any better.
Maybe you can learn something while you look for all those examples of the sky falling on the folks who throw a couple of pool tablets in their sea strainer.
Bromine treatment of non ferrous heat exchangers has been around a long long time and is very safe and effective. Show us where it is not. Bromine water treatment is not a "he-man" solution, it is a water treatment industry standard.
Methyl bromide is a fumigant gas and has about as much to do with water treatment as zinc phosphide has to do with anodes.
It is ignorance and mythology that has given bromine water treatment a bad name in the recreational boating world, not reality. Someone posted something on a website and repeating it makes the poster sound smart ... at least to folks who don't know any better.
Maybe you can learn something while you look for all those examples of the sky falling on the folks who throw a couple of pool tablets in their sea strainer.
Delfin
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You mean other than what is cited above, to wit: "Storage vessels are commonly constructed of steel lined with lead, PVDF (and certain other fluoropolymers) or glass. If the bromine is 'dry' then Nickel or alloys such as Monel and Hastelloy can be used though all are susceptible to severe attack in the presence of wet bromine. Titanium is unsuitable for Bromine duty (wet or dry) and should be avoided." and "Few metals are suitable for use in contact with 'wet' bromine (moisture content in excess of 30mg/kg)." So based on that, Rick, I would say most metals will be attacked by bromine. It takes about 2 ppm to kill Zebra mussels, but bromine tablets will deliver about 15 times that much, which is why pool pumps are built with seals and metals capable of holding up in a chlorine or bromine environment. I can Google that for you if you need more information on the subject.
Yes, at 2 to 3 ppm, not 30 ppm, which is what bromine tablets would deliver. And that is fresh water, by the way. As noted, in salt water the chemical reaction is rather different with the production of highly corrosive chlorine or bromine gas. That is why recommending it to someone who doesn't know better is irresponsible, and why manufacturers of marine a/c systems tell you not to do it.
My impression from JD is that he didn't care much about corrosion since he hadn't "seen" it occurring inside the engine block of his genset or the coils on his a/c. While my suggestion was sarcastic, if all you want is to kill critters, then it is hard to beat methyl bromide, and that suggestion is only slightly more insane than suggesting mixing salt water with bleach.
Yep, bromine is perfectly safe at the dosages it is used at for water treatment. And, if you can figure out a way for the OP to inject 2 ppm into his raw water loop on a continuous basis without going broke rather than the 30 or so he would get with tablets, and you can deal with the out-gassing interaction with salt water (not a problem with fresh drinking water), then please let him and the rest of us know how to do this.
Perhaps. 2 aspirin can help a headache. 30 aspirin can eat a hole in your stomach. Since you seem completely ignorant on this subject and how this particular chemical is dosed for different applications and environments, as well as the content of the information you cite as well as basic chemistry, I'm betting that whatever I learn will come from some source other than you. Some things never change.
RickB
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Geez Delphin, as usual you read just enough to jump off the deep end again. Pure bromine liquid is safely stored in metal containers, but add just a touch of moisture and the characteristics change dramatically. It becomes very corrosive. But add a tiny amount of bromine to water and it is a harmless biocide ... sort of like chlorine.
We aren't talking pure bromine storage and transport here despite how well that serves whatever purpose you are struggling to push at the moment. If you want to argue about this stuff, find someone who is willing to humor you.
In the meantime let us know when you find some horror story about someone whose boat dissolved because he put a couple of pool tablets in his sea strainer ... after all, that is what the discussion was about until you chimed in with your usual ignorant crap.
And who besides you said anything about using "chlorine gas" in their circ water? Jeez you do go over the edge quickly.
We aren't talking pure bromine storage and transport here despite how well that serves whatever purpose you are struggling to push at the moment. If you want to argue about this stuff, find someone who is willing to humor you.
In the meantime let us know when you find some horror story about someone whose boat dissolved because he put a couple of pool tablets in his sea strainer ... after all, that is what the discussion was about until you chimed in with your usual ignorant crap.
And who besides you said anything about using "chlorine gas" in their circ water? Jeez you do go over the edge quickly.
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Delfin
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When you get to the point where you understand the difference between 2 ppm and 30 ppm and fresh water and salt water get back to me. Or perhaps try a little experiment. Go to a hot tub retailer and buy some bromine or chlorine tablets. Take a bucket of sea water and drop the tablets in. Preferably you'll have some organic matter supplying ammonia in the sea water because that will make the experiment ever so much more fun. Stick your head in the bucket and take a deep, deep breath. Or perhaps just throw a copper nail in it and come back in a few hours and see what color it is. Can't wait for your report.
And no one is suggesting that anyone's boat is going to dissolve. I merely pointed out the reasons why many manufacturers of marine a/c systems strongly advise against using chemicals of any kind, much less bromine, to clean out the a/c loop. When they do recommend cleaning, they recommend using a dilute acid solution for a simple reason. Halogens like Bromine react vigorously with copper to form copper bromide, while it takes hot acid to dissolve copper. But that veers into chemistry, which you have demonstrated is not your strong suit, so I'll make it simple. Weak acid pretty much ok because it doesn't dissolve copper, weak bromine bad because it does.
Perhaps it's time for you to stop digging....
RickB
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http://www.stabilizedbromine.co/pdf/BCDMH Tech Booklet.pdf
"Typical Values for BCDMH G and BCDMH Tab
Percent Active Ingredient 98.0
Weight Percent Active Bromine 32.4"
......................................................................................
http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA557490
http://ir.library.oregonstate.edu/x...16697/Davis_et_al_JGR_1997.pdf.txt?sequence=3
..................................................................
"The bromine canister is attached to the SBE16 flushing circuit between the fluorometer and the transmissometer. It maintains brominated water that prevents the growth of phytoplankton inside the circuit and the sensors, in-between measurements.
The two methods have been tested during a dedicated experiment in the Aegean Sea and have proved to offer an efficient anti-fouling protection for at least three months"
http://hal.archives-ouvertes.fr/docs/00/29/84/16/PDF/osd-3-1399-2006.pdf
"Typical Values for BCDMH G and BCDMH Tab
Percent Active Ingredient 98.0
Weight Percent Active Bromine 32.4"
......................................................................................
http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA557490
http://ir.library.oregonstate.edu/x...16697/Davis_et_al_JGR_1997.pdf.txt?sequence=3
..................................................................
"The bromine canister is attached to the SBE16 flushing circuit between the fluorometer and the transmissometer. It maintains brominated water that prevents the growth of phytoplankton inside the circuit and the sensors, in-between measurements.
The two methods have been tested during a dedicated experiment in the Aegean Sea and have proved to offer an efficient anti-fouling protection for at least three months"
http://hal.archives-ouvertes.fr/docs/00/29/84/16/PDF/osd-3-1399-2006.pdf
Keith
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Never used bromine tablets, nor chlorine pool tablets. I use Clorox toilet tank tablets, and have been for about 20 years. They are inhibited so as not to corrode the metals in a toilet tank and have never done any damage to my AC system, nor other systems that use raw water. I break them up and use about 1/2 a tablet every time I clean the strainers. Works well.
Delfin
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Like I said, quit digging. You're starting to make a fool of yourself.
From the first document you referenced but apparently didn't read or perhaps understand:
"Examples of dosaging amounts of BCDMH biocides for the corresponding amounts of water to achieve 1 ppm bromine residual are as follows:"
1 ppm. Bromine tablets that the OP was asking about deliver 30 times that amount. Can you understand that there is a difference between the reactivity of one dosage that is a minimum of 30 times greater than another? I say a minimum because with the cannister system the OP was asking about, or JD's and your recommendation to just throw a couple of bromine tablets into the water strainer completely ignores the reality that bromine tablets are designed for FRESH water, not SALT water, and the presence of organics and NaCl results in a very different level of solubility. That's why the system you reference but don't understand specifies expensive equipment to ensure that you don't have more than 1 ppm continuous presence of the element in the water. Or are you suggesting that the amount of this element the copper piping an a/c system is exposed to has no impact on corrosion?
Tell you what, Rick. Don't answer. Save both of us and anyone else suffering through your continuing defense of ill-informed nonsense the grief. As usual, you respond to a simple question from someone on whether they can use bromine tablets to suppress algae growth with descriptions of systems like the one referenced above that due to its complexity, cost and totally different dosing capability has no relevance to the question of the OP, or any possible solution of value to a trawler owner.
Delfin
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Probably just fine. I suspect this product bumps the chlorine in the water by a couple ppm and probably is harmless to metals, notwithstanding the fact that Chlorox has settled a class action lawsuit that claimed the product ate the metals in toilets.
RickB
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It is a fool's errand to try to tell you anything, that is for sure.
I am still waiting for you to describe all the horrible results from people putting pool tablets in their strainers ... surely you can provide more than insults and attacks to support your contention that doing so is either dangerous or damaging.
Put up or shut up is the operative phrase and so far you have only attacked my contributions (and made lame attempts to attack me personally) that bromine is routinely used as a biocide in seawater systems.
So where is your information Delphin or is it just more blustering?
Delfin
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Not so much. As I said before, I never said that disaster would occur if people put pool tablets in their strainers. I merely pointed out what eludes you - that 1 or 2 ppm of a compound is less than 30 ppm of the same compound. That heating it up, as JD did by running the 30 ppm of the compound through his engine block makes the compound more reactive. That adding the compound to salt water makes it even more reactive. And that the compound is reactive with copper, which is found in the system the OP wants to introduce it into. This isn't bluster, it's just chemistry. But then again, facts, like chemistry, have never been your strong suit.
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