Compressing CO2

Avis

Is there a way to build a rig so that I could compress CO2 gas to apressure of roughly 7MPa?

I am building a CO2 Thermosyphone and need high pressure CO2 in order to get convection to occur.

Any help or advice would be greatly appreciated

Enthalpy

At 70b it liquefies at 300K.
http://encyclopedia.airliquide.com/i...r_Pressure.GIF
Are you pulling our leg?

Q_Goest

If you only need a relatively small amount, high pressure cylinders would be the way to go. If you're an industrial user, purchasing it as a liquid and maintaining it in a refrigerated liquid storage tank is common. The liquid can be pumped by a single stage reciprocating machine.

Talk to your industrial gas supplier to see what's best for you.

Avis

Exactly high pressure will cause co2 to liquefy thus at roughly 31 degrees it will change state and evaporate.

I am a student and I am building this as part of my degree project. We do not need much. We have a very limited budget. I haven't had any experience in doing this so I'm basically learning from scratch.

Enthalpy

Buy CO2 ice cold at 1atm, enclose it (with free volume!) cold at 1atm and warm it enclosed to room temperature so it gets liquid+vapour at 70b, use it.

You're aware that expanding the gas will cool it and the rest of the tank as well, are you?