7 replies to this topic

[titim]

hi every one

i have simulate a crude oil in HYSYS but in result i have 1.0 for vapour/phase fraction, that in reality not true, what is the mistake that i do to have this resultsmust be

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[serra]

if you know that at those conditions a liquid phase must exist possibly the wrong result is the result of  uncorrect characterization procedure,

you can repeat the procedure and examine the list of generated *pseudo* components,

you may simply test the results solving a series of flash operations (vaporization..) which is my preferred way to test with Prode.

Characterization procedures are simply but may require some care to select the correct values to enter.

you may also compare values, the different simulators may introduce little variants but  given similar inputs and correlations the properties for generated pesudo components shouldn't be too different...

[ziron]

Hello titim,

 

I used the data provided by you to generate the crude in Unisim and I obtained Vapour / Phase Fraction = 0.876.

[PingPong]

You only have the TBP curve up to 74.4 wt%, so Hysys extrapolates in some way, that is obviously too optimistic.

It is an illusion to think that Hysys knows what you don't know.

 

Without more TBP data you can not accurately simulate anything.

 

Is this crude Hassi Messaoud 46 ^oAPI ? I don't have a crude assay of that, but I do know that it contains some 0.2 % asphaltenes, so its TBP endpoint will be above 800 ^oC. What the shape of the TBP curve between 380 and 800 ^oC is is anybody's guess. Best is to look at similar API crudes.

[titim]

You only have the TBP curve up to 74.4 wt%, so Hysys extrapolates in some way, that is obviously too optimistic.

It is an illusion to think that Hysys knows what you don't know.

 

Without more TBP data you can not accurately simulate anything.

 

Is this crude Hassi Messaoud 46 ^oAPI ? I don't have a crude assay of that, but I do know that it contains some 0.2 % asphaltenes, so its TBP endpoint will be above 800 ^oC. What the shape of the TBP curve between 380 and 800 ^oC is is anybody's guess. Best is to look at similar API crudes.

 

hi, yes crude of HASSI MESSAOUD

[PingPong]

You need to obtain a Crude Assay or SimDis (such as ASTM D2887) of that crude if you want to do any accurate simulations. You should make that clear to the person who asked you to do this work.

 

Is that 662 ^oF at 36.26 psia supposed to be the outlet conditions of the crude charge heater in a CDU ?

If so, is that an existing CDU or a new one?

[titim]

hi

yes that from an existing CDU (2.2 bars and 350 °C

[PingPong]

Note that the 36.26 psia that you used corresponds to 2.5 bara, not 2.2 bara.

 

In an existing CDU you could try to use the actual quantities of all products, in combination with their composition (of gas and LPG products) and ASTM distillation (D86 for gasoil and lighter, D1160 for atm, residue), to reconstruct the crude feed.