# Calculate volume based on Compositional analysis

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Good Morning,
I am not a chemist nor student but looking to gain some knowledge if some of you would share. My company trucks in a mixed NGL product where we weigh in and weigh out the tanks to determine the net weight of the total load. For each incoming load we receive an analysis with all of the components (Nitrogen, CO, Methane, Ethane, Propane, Iso-Butane, N-Butane, Iso-Pentane, N-Pentane and Hexanes plus)
Our goal is to determine , based on each load's analysis, how many gallons there are of each component in the load.
I have put together a spreadsheet(attached) based on a similar application we once used which uses each component's Mole %,Molecular wt., lbs. of component per gal, etc. , but I'm not sure I can rely on it's accuracy even though I feel it is close.
I may not be posting under the right category for this particular topic, if not please advise. Any help is much appreciated.

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These are common chemicals so all you have to do is look up the density (for the temperature) in lbs/gallon and divide your load by that density and that will give the gallons in the load.

Make sense?

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Not sure I understand your mixture.

The boiling point of methane is -258oF and the boiling point of hexane is + 154oF

Is the stuff pressurised?

You also need to distinguish between lbs mass and lbs weight, which are you using?

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Typically there actually is no methane in this mixture as it should all be cooked out at the refinery prior to being sent to our facility. Normally the mixture we receive is a mixture containing C2 thru C6+.

I'll try to explain the spreadsheet calculations I'm using. However, as I mentioned earlier I'm not sure this spreadsheet is using the most efficient way to breakdown the components of the mixture from the Analysis' Mole %

The spreadsheet uses the Mole% from the individual components from the load chromatography analysis.

Lbs./Mole = Mole % x Molecular weight (of component)/100

Fractional Component by weight = Lbs. per Mole / Sum of components Lb./Mole

Lbs. of component= Net weight of tank x Frac. component by wt.

Actual individual component gallons = Lbs. of component / Lbs. Component per gallon.

Thanks again.

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