UV Sterilizer for Water

[10_degrees_play-doh]

I had a bit of an apostrophe recently: UV-C is a long-established means of sterilization and chlorine neutralization, enjoying a bit of a rediscovery these days with COVID. I'm thinking it would be a great way to treat say, yeast-rehydrating water, or priming sugar water. Any thoughts? Reasons it's not used more already?

 

[day_trippr]

"epiphany"

I doubt most folks have even a conceptual familiarity with UV-C, never mind have one in their homes.

I do have a whole-house UV-C module in our second home, and it cost way more than the countertop microwave I use in my primary residence for sanitizing yeast starter water...

Cheers!

 

[10_degrees_play-doh]

heh forgive the malapropism...

As I mentioned though, the technology does seem to be enjoying a sort of renewed interest these days due to COVID, and there are some lights on Amazon as low as the $20 range: Amazon.com

I figured the advantage would be not having to wait for microwave-boiled water to cool down.

 

[Beholder]

I also have a UV-C whole house unit - if you have one anyhow, then sure, one less thing to worry about, but would be costly for a unitasker. Funny enough, I never thought about the water for the purposes you mention, since I am also concerned with germs on the surface of the container I’m using not to mention those on the faucet outlet.

 

[day_trippr]

fwiw, those UV-C units appear to be surface-sanitizers only. I don't see any easily used to sanitize, say 1 or 2 liters of water, and intensity matters wrt getting disruptive energy all the way through a vessel of water...

Cheers!

 

[10_degrees_play-doh]

Perhaps, I was also thinking UV would fall into a sort of more energy, less penetration category along with most EM spectrum stuff, but apparently it's not so linear when it comes to light... UV-C seems to be right at the threshold between really shallow and really deep:

 

[RufusBrewer]

My reluctance to use one would be a question of dosage. How much UV energy is enough to do the job AND did I apply enough?

I cannot see germs, I cannot see UV. I would need to be confident that I literally did an overkill job.

 

[Beholder]

UV systems for water are arranged in a coaxial tube to ensure light penetration. Check out the link below for the details on a well designed system. Oh yeah, needs micron filtration as well to ensure the glass doesn’t foul and interfere with the light.

https://www.uswatersystems.com/pulsar-ultraviolet-disinfection-system-by-us-water-systems.html

 

[10_degrees_play-doh]

Interesting, I never heard of aquarium/aquaculture type uv filters requiring micron filtration, though they also probably don't have to be 100% effective... Maybe it's not really practical given current technology, though I suspect there is a certain intensity and time, plus vessel design that could work. I don't know that I have the time or gumption these days to look up light intensities, microbe reduction rates, crunch numbers, design something effective, etc... The ones on Amazon for $20 do seem a little too good to be true and some of the reviews indicate they may be fairly weak or out of the proper wavelength. There are some legitimate UV-C LEDs nowadays, in addition to the tried and true older technologies, and at least that LED technology is bound to continue to mature. There is info on intensity, time, effectiveness out there; I skimmed a decent article for hospital uv sanitization recommending 7 ft and 30 minutes for surface treatment that included light intensities and microbe reduction rates. There also cards and meters that can measure the intensity. I doubt I would do it any time soon, but I still have a curious itch here, and a rough test could maybe be sinking a uv card in a ziploc bag to the bottom of a flask, placing that flask in a kettle, installing a light in the lid, making a little sterilization chamber and seeing if the light makes it to the bottom...

Anyway, thanks for the input, all. Cheers!