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Convert Distillation to TVP/RVP

Convert Distillation to TVP/RVP

Convert Distillation to TVP/RVP

I am trying to do some preliminary work on a crude project, and have been warned that the particular crude has exhibited high vapor-pressure properties.

In the lab assays, I have alot of informtion, but no direct RVP or vapor pressure info.  How do I convert to get TVP or RVP?  Useing D86 Distillation data?  Simulated distillation?  Other data?  Just looking for a quick range of VP, to see if I need to anticipate IFR, vapor recovery, etc.

RE: Convert Distillation to TVP/RVP

What type of lab data do you have?  

I've usually used a process simulator to input a D86 or TVP curve with the light end analysis and allow the simulator to develop the crude pseudo-components.  Then you can get the TVP for a given temperature and most process simulators will also give you a RVP.

RE: Convert Distillation to TVP/RVP

The lab data is very prolific.  I have a full assay on the crude as well as major cuts.  It's got (for crude) a simulated distillation curve (D7169) and PONAOX(U) analysis.  AS well as the other standard stuff - gravity, viscosity, etc.  What I don't have anywhere is any mention of vapor pressure itself.

See attached distillation curve.  

I'm not a chemical or refinery guy - generally I do tank farms.  But i have a client who's talking with a potential customer (who owns the crude) and we're trying to determine if the crude will require any extensive vapor controls.  I've been told by others that if the crude has a TVP at storage temp > 11.1 psia, the storage tanks will need vapor control (combustor, eductor recovery, etc).  Any of these options is more costly than currently planned.  So I'm trying to get a feel if we need to be worried or if this stuff doesn't have enough light ends to worry about.   

RE: Convert Distillation to TVP/RVP

why do not put the crude sample in a closed bottle, remove incondensables (for example by displacing all initial air) control the temperature (electric bath or equivalent system) and measure the pressure in the bottle ?
There are specific (and quite complex) measurement apparatus for both TVP and RVP (see ASTM standards) but I would expect that you may get a realistic value of TVP with the above method.

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