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SteveAD:6148215:my recommendation would be to get a couple of flow meters with control valves McMaster-Carr set the pressure the same on both sources then you can tweak flow rates to get the right mix
I am a researcher at the UC Davis MIND institute and the lab needs to mix some gasses in-line prior to dispensing and none of us in the lab are confident we have the right idea. Our lab doesn't have a lot of funding, so we can't afford a normal gas mixer but in my research it seems that these are not actually necessary and I think that mixing in-line shouldn't be too hard.
The lab wants to have a gas mixture of 5% CO2 and 95% Air. The gas is going to constantly blow at a low rate (a few L / min) into a small plastic container (4"x6"x2") that has a 2" diamter hole in the bottom.
I was thinking that all that we needed was to maintain a proper ratio. My idea was to have an air tank set to 95 PSI and a CO2 tank set at 5 PSI and then have the lines merge before reaching the end.
Would this work? Would it be roughly 5% CO2 and 95% air?
How much blended gas do you need and how accurate do you need the mix to be?
If you used a scuba-style mixing stick and tested the gas mixture with a scuba-style O2 sensor located after the stick,
an O2 content of 19.9% would be a CO2 content of around 5%. If you could test the O2 to within .2%, then the Air content
should be good to within 1%, hence the CO2 content to within 1% (meaning between 4 and 6% CO2).
Not the most precise way to do this, but it could be cobbled up on the cheap.