Ozone detector.

I would like to use one of these for automatically controlling a water disinfection tank. Primarily to purify rainwater and eliminate any cryptospyridium that may be present

The arduino one measures gas but i want to measure the dissolved concentration.

Any ideas ? Is there any way to relate the dissolved concentration to the gas in a headspase ?

Boardburner2: I would like to use one of these for automatically controlling a water disinfection tank. Primarily to purify rainwater and eliminate any cryptospyridium that may be present

The arduino one measures gas but i want to measure the dissolved concentration.

Any ideas ? Is there any way to relate the dissolved concentration to the gas in a headspase ?

There's likely a correlation between volume, pressure, temperature, where if you know several you can determine the one. freshman physics: pV = nRT pressure, volume, temperature, a constant R, and n = number of molecules. Problem is there will be molecules present also, yes? O2, N2, CO2, etc.

My town (city) uses Ozone to purify water, comes out nice & soft (or maybe that's due to other minerals) so it suds up nice, the water tastes good, and there is no chorine smell. I don't know much more about how it's actually done.

CrossRoads: There's likely a correlation between volume, pressure, temperature, where if you know several you can determine the one. freshman physics: pV = nRT pressure, volume, temperature, a constant R, and n = number of molecules. Problem is there will be molecules present also, yes? O2, N2, CO2, etc.

Yes. Being rainwater it is rather acidic depending on the wind direction so NOx is likely a problem although i use a limestone bed to mitigate this , PH is already monitored before ozone is used though. Cheap ozone sensors are also responsive to NOx .

I am hoping that i can take a sample into a chamber with a head space and make a meaningful measurement with a cheap gas sensor. It is complicated by the fact that ozone can have a short half life which depends upon organic contamination of the water. This BTW also causes problems with my current measurement method which is a chemical , one shot , colourmetric/titration method.

CrossRoads: My town (city) uses Ozone to purify water, comes out nice & soft (or maybe that's due to other minerals) so it suds up nice, the water tastes good, and there is no chorine smell. I don't know much more about how it's actually done.

Ozone does not materially affect water hardness although it can oxidise metals if present, it is of little use where there are large amounts of organic contamination though, water should filtered and sedimented first before use. Rainwater although quite soft can be very filthy when collected from roofs , even glass ones.

I did Chemistry as a degree, but chose Astrophysics as my elective and Life Chemsitry for a module rather than the Atmospheric...but...

Can you place a sample of the water in a low pressure chamber and does ozone have any particular strong IR/UV absorption bands?

Johnny010: Can you place a sample of the water in a low pressure chamber and does ozone have any particular strong IR/UV absorption bands?

UV adrobtion is a way of measuring ozone concentration but is influenced by water quality.

Low pressure chamber like UV adsorbtion increases cost.

I am a really cheap person. :)

This seems to be coming down to a simple no.

You don't want to measure using spectroscopy...conductivity is a no-go unless you have some sort of selective filter ($$$) so yeah.

I think you've stuffed this one.

Johnny010: I think you've stuffed this one.

Yes i think so At least within what i can afford.

As part of this i also want to measure turbidity but am not sure how commercial meters work.

My thought is to use a couple of photodiodes to measure transmission and back scatter.

UV or infrared ?