Why CO2?

[Liftoff]

As I said above, it's not a bi product, the CO2 we use is done with the sole intention of creating CO2.

A quick google search shows that not all liquified Co2 producing companies follow that route... some do use by-products from other industries to process it into a liquid....

read here:

http://www.uk.airliquide.com/en/prod...vironment.html

[leorcc]

The gas production company I worked for (Messer) made CO2 as a byproduct of producing acetylene, but that was in no way sufficient for all CO2 demand, particularly welding gasses, so it was also made on another line specifically by basically burning gas.