Bromine as biocide in cooling tunnel
I had a conversation with my chemical guy recently about adding bromine into the mix as a biocide in my cooling tunnel. He had brought it up a couple years back but the idea was shelved. Has anyone else implemented a switch from just chlorine to chlorine + bromine in their facility? If so, did a noticeable decrease in microbes occur? I want to explore this option, but I feel like I just don't have anything to back me up besides what the guy trying to sell it is telling me.
I had a conversation with my chemical guy recently about adding bromine into the mix as a biocide in my cooling tunnel. He had brought it up a couple years back but the idea was shelved. Has anyone else implemented a switch from just chlorine to chlorine + bromine in their facility? If so, did a noticeable decrease in microbes occur? I want to explore this option, but I feel like I just don't have anything to back me up besides what the guy trying to sell it is telling me.
Hi DSI,
I don't quite understand the chemical specifics you are referring to.
Are you saying that you are routinely injecting Chlorine gas in the cooling environment to kill airborne bacteria ?
Sounds extremely unusual, if not hazardous ?.
I believe you might be referring to a cooling tower? Do you trust your chemical guy? In my experience, they are the experts so I would work with him and try his recommendation. I believe we used bromine/chlorine at my previous position.
We use a cooling tunnel that sprays chlorinated water on the bottles since they are bottled hot. To keep our microbial counts low, I have had to spike the chlorine levels above 3ppm recently. The main issue is this also damages our cooling tunnel belt. If we add the bromine, it will cut our chlorine use in half. I'm trying to find if anyone else has had any experience with using it.
We use a cooling tunnel that sprays chlorinated water on the bottles since they are bottled hot. To keep our microbial counts low, I have had to spike the chlorine levels above 3ppm recently. The main issue is this also damages our cooling tunnel belt. If we add the bromine, it will cut our chlorine use in half. I'm trying to find if anyone else has had any experience with using it.
My guess is that the "chlorinated water" is actually sodium hypochlorite ?? Or something similar ?
My guess is that the "chlorinated water" is actually sodium hypochlorite ?? Or something similar ?
You are correct. Sodium hypochlorite is what is used.
I would suspect it's a decent biocide but my concern is if it was consumed inadvertently by consumers.
Rather than alter the chemicals have you done a root cause analysis on why micro counts have increased? Do you have some areas in the systems where biofilms have formed? Also the efficacy of chlorine is heavily pH dependent. It's hypochlorous acid which is the really great disinfectant but only small amounts of this are in equilibrium in a solution. The closer you get to neutral, the more effective it would be. But chlorine based disinfectants are notoriously bad at coping with debris or biofilms. Does your whole system need a good flush out, clean and maybe descale?
I would suspect it's a decent biocide but my concern is if it was consumed inadvertently by consumers.
Rather than alter the chemicals have you done a root cause analysis on why micro counts have increased? Do you have some areas in the systems where biofilms have formed? Also the efficacy of chlorine is heavily pH dependent. It's hypochlorous acid which is the really great disinfectant but only small amounts of this are in equilibrium in a solution. The closer you get to neutral, the more effective it would be. But chlorine based disinfectants are notoriously bad at coping with debris or biofilms. Does your whole system need a good flush out, clean and maybe descale?
It was actually very bad earlier. I performed a deep clean a month back that took 2 full days. The counts were over 500 cfu/ml a month ago, but with periodic spiking of the chlorine to over 3 ppm for an hour or two at a time, I have brought the counts down to 14 cfu/ml. My only concern is that higher levels of chlorine damage the cooling tunnel belt. To replace the belt if it breaks would be north of $70,000, not to mention the cost of not running production for more than a day.
I was told that with the addition of bromine, I would drop my chlorine usage in half, decreasing the stress to the belt. Before I pitch this idea to the factory owners, I want to find how it has worked in real world situations.
It was actually very bad earlier. I performed a deep clean a month back that took 2 full days. The counts were over 500 cfu/ml a month ago, but with periodic spiking of the chlorine to over 3 ppm for an hour or two at a time, I have brought the counts down to 14 cfu/ml. My only concern is that higher levels of chlorine damage the cooling tunnel belt. To replace the belt if it breaks would be north of $70,000, not to mention the cost of not running production for more than a day.
I was told that with the addition of bromine, I would drop my chlorine usage in half, decreasing the stress to the belt. Before I pitch this idea to the factory owners, I want to find how it has worked in real world situations.
Hi DSI,
Sorry my ignorance but i'm having problems understanding yr above numbers. And yr Process.
You mention 500cfu/ml. One ml of what ? The liquid inside the bottle ? Surely this is unrelated to the ppm Cl2 in the spray ?
To my understanding a (spray-impacted) surface count would usually refer to an area of something ?
Hi DSI,
Sorry my ignorance but i'm having problems understanding yr above numbers. And yr Process.
You mention 500cfu/ml. One ml of what ? The liquid inside the bottle ? Surely this is unrelated to the ppm Cl2 in the spray ?
To my understanding a (spray-impacted) surface count would usually refer to an area of something ?
The water in the cooling tunnel is sprayed out above the bottles then falls down to a reservoir below the belt. This water is continually cycled through pumps and sprayed back on to the bottles to cool them down.
I test the water in the reservoir through vacuum filtration. I plate for TPC, yeast & mold, P.a., and entero. The counts I am referring to are TPC.
Another option could be to not use chlorine since it's so harsh, especially since your bottles are capped at this time, so you don't need to worry about contacting product. Why not a low level quat mix in your recirculated water? Would be friendlier to your equipment and shouldn't foam at low levels.
The water in the cooling tunnel is sprayed out above the bottles then falls down to a reservoir below the belt. This water is continually cycled through pumps and sprayed back on to the bottles to cool them down.
I test the water in the reservoir through vacuum filtration. I plate for TPC, yeast & mold, P.a., and entero. The counts I am referring to are TPC.
Hi DSI,
I'm a bit puzzled by yr numbers / process.
I assume the reservoir water, as is, is rated as "potable". Otherwise yr cooling/recycling procedure IMO would not normally be FS acceptable. TBH I have some doubts that recycling such as you describe is itself legally acceptable ?. But maybe in Canada ?. IMEX water in process flow "washing" stages is 100% rejected (and yes, at a significant cost).
If potable, I assume the reservoir's natural TPC is low (required to be < X presumably, IIRC maximum X for EC is in the 20-100cfu/ml range but I think USA is a higher tolerance).
I'm not sure what you mean by "spiking" but IMEX "potable" water when chlorinated by a continuous injection pump/NaOCl solution so as to achieve 3ppm of free Cl2 (measured by DPD) will have a TPC of 0-10 cfu/gram. Typically nearer the zero end. So i don't understand the 500 /14 data.
What is the Cl2 level at start of recycle ? If the bottles are clean, i would assume > 0ppm, ie Cl2 still detectable.
IMEX of SS / Plastic conveyor -freezer (-18degC usage) belts, daily cleaning with water hypo-chlorinated at 3ppm had negligible impact. And similarly for ambient running plastic belts.
It might depend on the particular food-grade plastic but i would have expected most commercial products are assured as unaffected by such treatment.
Another option could be to not use chlorine since it's so harsh, especially since your bottles are capped at this time, so you don't need to worry about contacting product. Why not a low level quat mix in your recirculated water? Would be friendlier to your equipment and shouldn't foam at low levels.
Really, really down with this. Quats are much maligned nowadays but so effective, normally equipment safe and more effective in the presence of debris than halides. But I would still try and sort out why your loading is so high!