Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

An Overview of Process Simulation

•What is needed?

•What are the steps?

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Lean Oil Absorption System – What do we need to simulate?

Data on the materials being processed -

Physical properties –•vapor pressure•density•heat capacity•etc.

Transport properties –•viscosity•thermal conductivity•etc.

For pure components and distillation curves (DB or input)

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Lean Oil Absorption System – What do we need to simulate?

Models of the equipment – Unit Operations

Distillation

Heat exchangers

Pumps

•Reactors•Pipes•Compressors•Etc.•56 in Chemcad•Can add own

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Lean Oil Absorption System – What do we need to simulate?

Models of behavior of materials (laws of thermodynamics) -

•Phase behavior•Reaction behavior•Heat flow behavior•Momentum behavior

Can be calculated based on equilibrium or rate based –•mass transfer•heat transfer•reaction rates•pressure drops

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Numerical methods –•modular sequential•equation based•combination

Calculation mode –•steady state•dynamic

Lean Oil Absorption System – What do we need to simulate?

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Step 1: Draw the flowsheet

Graphics mode –•UnitOps•Streams•Text•Symbols

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Step 2: Select engineering units

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Step 3: Define components (data)

Pure components from the database,crude distillation curves from the database,or, user input distillation curve(s).

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Step 4: Select thermodynamic options

K-value (phase equilibrium) options,Enthalpy (heat balance) options.

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Step 5: Specify feed streams

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Step 6: Specify the equipment

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Step 7: Run the simulation

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Step 8: Draw the PFD

Stream data boxes

UnitOp data boxes

T, P, F boxes

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Step 9: Size equipment

Chemstations, Inc – Houston, TX – 800.243.6223 – http://www.chemstations.net

Step 10: Generate a report