CO2 emission factor

[newengr]

Quick question, whats the density of CO2 in lb/ft3?

I was trying to calculate a CO2 emission factor (lb/mmBTU) ...I have the amount of gas in scfm....and also the BTU/unit to give me the energy consumed in MM BTU.....

For example:
I have 1E6(cf) of a gas thats composition is %H2 is 86.13
%CH4 is 9.58%, %CO2 is 2.38%, %CO is 1.44%, %methanol is .27%, %N2 is 0.16%, %H20 is .02%....All I have to do is convert the 1E6(cf) to (lb) by multiplying by CO2 density...Then I would multiply by .0238 to have the amount of CO2 in lb.....Then divide by energy consumed (mmBTU) to get CO2 emission factor which is (lb/mmBTU)

 

[TD2K]

Multiply the volume by the amount of CO2 (2.38%, I assume this is mol/vol%) to get the volume of CO2.

If the pressure isn't that high (and by cf I think you might be referring to scf so you are fine there), use the ideal gas law to calculate the density, PV = ZnRT. If you re-arrange it, density = PMW/ZRT, P is the absolute pressure, MW is the mol weight, Z is the compressibility factor, R is the gas constant and T is the absolute temperature

 

[newengr]

Will I even need to use density if I have MW because
1E6scfm *.0238mol/scfm*44lb/mol = ## lb..then divide by mmBTU to get CO2 emission factor....

 

[TD2K]

That's another way of doing it. I'm not sure about the 0.0238 mol/scf (the minute should not be there). I've used 379.6 scf/lbmole or 0.00263 lbmole/scf.