2 replies to this topic

[LoaiSowwan]

Dear all, 

so i have this project at my college which is designing a distillation column. the gave me a flow rate of 20,000 barrels per day and my feed in a NGL consisting of Ethane and Propane. And i need to convert the feed flow rate to mass flow rate. I understand i should find the density of NGL so i can use the equation Density = mass flow rate / volumetric flow rate.

can any one help me to find the average density of NGL at -90 F temperature ?

it's okay if the density isn't 100% accurate, i just need a number to start with in my calculation.

 

any help would be appreciated.

 

Kind Regards, Loai

[Bobby Strain]

The volumetric flow is generally expressed at standard conditions. Sometimes 60 F and atmospheric pressure. You really need to know the composition, too. Ask your instructor to provide it. Or make your own assumption. My guess is that somewhere you have it. NGL usually contains methane through about C8 hydrocarbons.

 

Bobby

[MrShorty]

To clarify: NGL (L standing for liquid) implies to me that you are looking for liquid phase densities, is that correct?

 

Procedure 1: Solve your favorite equation of state for volume/density. Cubic EOS's are usually the easiest, so pick one (Peng Robinson is a favorite), gather the necessary input data (critical constants, composition, temperature, pressure, etc.) and solve the EOS. I am assumiing that you have seen this before in your studies and that this is not completely new to you.

 

Procedure 2: If you have equations for the density/volume of the pure components, you can assume "ideal mixing" and assume that the volumes are additive. Again, I will assume that you have seen this kind of calculation before and can apply it to your current scenario.

 

What part of either of these do you get stuck on?