I store liquid CO2 at 20 Barg on my site. This is a new installation designed and constructed to European standards. The vessel is rated to 22 Barg and -40oC to +45oC. We have pressure relief valves set at 22 Barg.

My question is:- Is -40oC an acceptable design temperature?

There is old UK HSE guidance saying -50oC but this has been revoked. The new guidance says it should be designed to a recognised code - a great help!

Can someone send me a chart showing CO2 temperature vs pressure?

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