CO2 different?

[chua]

Hi

Is there any different in the CO2 when we top up at different LFS?

It is because the previous top up in a particular LFS required 4bps to obtain my desired CO2 level.

Now, after topping up in another LSP required only 1bps to obtain the same desired CO2 level.

Why is that so?

Thks.

[budak]

CO2 is CO2..... but there are different grades available when it comes to commercial CO2 supplies, namely industrial grade (which contains a fair number of other gases and impurities mixed with the Co2), food grade (the stuff used in Coke and Pepsi, which is fairly pure), and pharma grade (which is almost pure CO2 and very expensive). Food grade Co2 is suitable for our use, and usually reputable suppliers like Soxal provide this.

[chua]

Thks Budak for the information.

So that means that some LFS are using food CO2 while others are using industrial CO2.

[juggler]

This was what I heard from the chap who did the CO2 top up for me at ChemGas when I asked him about food-grade CO2.
If I had understand correctly, he said for those tanks requiring "food grade" CO2, they just flush the empty tanks with Co2 from the same source a for some time before the top up.

Next time you guys can verify if you ever go for top ups.

[j1972]

Where is Chemgas and how much do they charge?

[bclee]

Basically, the purity difference of the different grade is minimal. As KF mentioned, if you buy food grade CO2, they will flush your CO2 tank before filling. And the CO2 will be monitored for impurities that will affect taste of food/beverages that it is used with. On the other hand medical grade CO2 are produced and supplied under very stringent control to ensure sterility.

Usually we will use industrial grade CO2. The cheapest of all.

I doubt it is the CO2 purity that caused the difference. Was there any other changes like adding a fan or change of filter or powerhead, etc.?

BC

[juggler]

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On 11/24/2003 3:07:27 PM

Where is Chemgas and how much do they charge?
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The info is in the LFS List above. Just give them a call and ask.

[geoffrey]

According to the supervisor in Chemgas, food graded CO2 is about 99% while industrial grade is about 95%. Don't think hospitals use pure CO2 or do they? I know only outlets for air, vacuum, O2 and nitrous oxide.

While CO2 is use in calibrating capnometer/capnograph but I doubt that can be qualified as medical usage.

Yes, they purge out first before refilling your tank with the new food graded gas and it cost more.

[bclee]

On SOXAL's product list, they have "Medical Carbon Dioxide" under Medical Gases category. Well... not sure what's its application.

BC

[confusekid]

The cost different is due to purity, higher purity need more refinement. It does not matter if it is 95% or 99%. 4% will not cause much of a different. Most likely some other parameter change, so that the CO2 used drop. If you are really concern about purity you can get Electronic grade CO2(99.9999%) but you will pay $1000+.