Process Simulation Lecture 1

Properties

•All items needed to fully define the physical property input

•Component selection and characterisation

•Select property package

Simulation

•Build/run models and review results

•Build and specify process flowsheets

•Create and run analyses (e.g. Case Studies)

To fully specify the stream we need:

1.Composition

2.Thermodynamic state

•Two of the following:     Pressure

                                                  Temperature

                                                  Vapour Fraction

3.  Flow, in either:           Mole

Mass

Volume

What is the stream condition when user adds VF=0

HYSYS interprets it as dew point (same as q)

What is the stream condition when user adds VF=1

HYSYS interprets it as bubble point (same as q)

When HYSYS calculates and shows VF=0…

Stream is sub-cooled (opposite of what user enters)

When HYSYS calculates and shows VF=1…

Stream is super-heated (opposite of what user enters)

What is envelope analysis?

•Vapour – Liquid (e.g. bubble/dew points; vapour quality)

What is property table?

Property trends over a range; selection of desired dependent/independent variables

What is default spec of a Separator unit?

No pressure drop

What is a model assumption for a separation unit?

Complete separation

How to do flash calculation on the stream?

Delete the temperature and set the vapour fraction do dew point (0) and vice versa