CO2 Heating and Condensation

[archemex01]

Hi all,

I am involved in designing a supercritical pilot plant. I have a two part question.

1) Finding the heat duty for heating liquid CO2 from -20C to 60C which is flowing at 300kg/hr at 100 bar. I came up with 48,000kJ by finding the specific heat (cp) from NIST tables for 100 bars at -20C and plugging it into Q=m*cp*dT. I just wanted to check if this is the right equation to use since there is also a phase change from liquid to supercritical.

2) Finding the cooling duty required to condense gaseous CO2 at 25 bar and 0C back to -20C.

I appreciate any help.

Thanks.

 

[PaoloPemi]

you can use tables and assume contant cp but I would suggest tools as NIST Refprop or Prode Properties, given two operating conditions these calculate directly the enthalpy difference with the help of a equation of state, you can use one of these tools to verify your result.

 

[MortenA]

need info on co2 - check this out:

http://www.union.dk/media/CO2-GB.pdf

Best regards

Morten

 

[archemex01]

Thanks for both replies.