Transcript Document 7535069
Aspen Tutorial
Terry A. Ring ChEN 4253
Process Simulation Software
• Steady State Process Simulation – AspenPlus – ProMax – ChemCad – Hysis – HySim – ProSim – CADSim – OLI Process Simulator – KemSimp – Chemical Workbench Code – Ascend IV • Dynamic Process Simulation – Aspen Dynamics – CADSim – Simulation Solutions, Inc.
Types of Simulators
• ProMax • Equation Based – Solves block by block • Aspen • Puts all equations into one Matrix equation – Solves all Mass and Energy Balances at once
Basic Elements of a Simulation Program *
Thermodynamics Numerical Methods Thermodynamics
*
Other Subjects : Solid Mechanics, Manufacturing Science Economics * - Reaction Engineering, Mass Transfer, Heat Transfer, Fluid Mechanics
Towler and Sinnott , “Chemical Engineering Design : Principles , Practice, Economics of Plant and Process Design” , Elsevier (2008)
Aspen
• Aspects of Aspen – Next Button – Many units that perform a given function • Degrees of Freedom are chosen for you – Setup for kinetic reactions are tricky – Accounts for particle sizes • Simple block models – Automatic Plant Costing (Aspen Economics)
Steps to Run
• Aspen ( Left Hand Bar ) – Wiring up Process – Title – Components – Thermopackage – Process Flow Sheet • Feed Stream • Unit Specifications – Fixed degrees of freedom – Run – Results – Report
ThermoPackage Choice
• Questions for ThermoPackage Choice • Are the components? – Polar – Non-Polar • System Pressures?
– P< 10 atm - ideal gas • Interaction Parameters Available?
Figure 1
Eric Carlson ’s Recommendations Non-electrolyte
Polar E?
Electrolyte Electrolyte NRTL Or Pizer R?
P?
E?
All Non-polar R?
Real Polarity Real or pseudocomponents Pressure Pseudo & Real Electrolytes P?
Vacuum Peng-Robinson, Redlich-Kwong-Soave, Lee-Kesler-Plocker Chao-Seader, Grayson-Streed or Braun K-10 Braun K-10 or ideal
Yes NRTL, UNIQUAC and their variances
Figure 2
Polar Non-electrolytes P?
P < 10 bar
ij?
No LL?
Liquid/Liquid P?
Pressure P > 10 bar ij?
Interaction Parameters Available Yes LL?
Yes No Yes WILSON, NRTL, UNIQUAC and their variances UNIFAC LLE LL?
No UNIFAC and its extensions Schwartentruber-Renon PR or SRK with WS PR or SRK with MHV2 ij?
No PSRK PR or SRK with MHV2
Figure 3
Yes Wilson NRTL UNIQUAC UNIFAC VAP?
No Hexamers Wilson, NRTL, UNIQUAC, or UNIFAC with special EOS for Hexamers DP?
Dimers Wilson, NRTL, UNIQUAC, UNIFAC with Hayden O’Connell or Northnagel EOS Wilson, NRTL, UNIQUAC, or UNIFAC* with ideal Gas or RK EOS VAP?
Vapor Phase Association DP?
Degrees of Polymerizatiom UNIFAC* and its Extensions
Bob Seader ’s Recommendations
Figure 4
Bob Seader ’s Recommendations Yes PSRK HC?
Yes PC?
LG?
Hydrocarbons Light gases Yes LG?
No Yes
E?
Electrolyte PC?
Organic Polar Compound No HC?
Yes PC?
No
Modified NRTL No E?
No Special: e.g., Sour Water (NH 3 , CO 2 , H 2 S, H 2 O) Aqueous amine solution with CO 2 and H 2 S
Figure 5 HC and/ or LG BP?
Narrow or wide Critical PR Cryogenic T?
Non- Cryogenic P?
Non-Critical SRK, PR PR, BWRS Very wide LKP BP?
T?
P?
Boiling point range of compound Temperature region Pressure region
Figure 6 Yes PC with HC Available PPS?
No BIP?
Not Available NRTL, UNIQUAC Wilson UNIFAC BIP?
Binary Interaction Parameters PPS?
Possible Phase Splitting
Hyprotech Recommendations
ProMax Guidance
(5 more pages like this)
Model Pure Binary Mixture VLE VLLE Notes EOS (Equation of State) SRK (Soave Redlich Kwong)
●
Peng-Robinson SRK Polar Peng-Robinson Polar Lee-Kesler
● ● ● ●
Tillner-Roth and Friend NH3 + H2O
● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● Gas Processing with No Methanol, Refinery Distillation Gas Processing with No Methanol Gas Processing with Methanol or NMP Gas Processing with Methanol or NMP Light Hydrocarbon Systems with H 2 S and CO 2 , No 2nd Liquid Phase Ammonia Absorption Refrigeration, Ammonia and/or Water Only
Problem-1
• Problem 5.12
• Alternatives in preparing a feed. A process under design requires that 100 lbmol/hr of toluene at 70F and 20 psia be brought to 450 F and 75 psia.
• Flow sheets using Peng-Robinson – Boil-Superheat-Compress – Pump to 75 psi-Boil-Superheat – Which process uses the most energy?
Design Spec
– What Then How (WtH) • What do I want to specify?
• What do I want to vary to control it?
Which System has the most Energy?
• Moving from T o , P o – STATE PROPERTY to T f, P f • Enthalpy change is the same if the end points are the same.
• Why is Boil then Compress not suggested? Heuristic 43
Problem -2
• Use Gibbs
CO
Minimization reactor in Aspen to determine
CO
2
H
2
H
2
H CH
3
OH
2
O
C
(
s
) the products of reaction at 10 atm and 200 C.
• Feed equimolar in CO and H 2
Sensitivity Analysis
• Produces Table of Results using a Do Loop to vary one (or more variables) • What Then How
Problem 3
• Use Equilibrium Reactor to determine reactor conversion for methanol reaction at 10 atm and 200C
CO
2
H
2
CH
3
OH
• Use sensitivity analysis to determine reactor conversion at a suite of temperatures
Problem -4
• Determine the resulting equilibrium at 10 atm and 200 C using an equilibrium reactor in Aspen with both of the reactions listed.
CO
CO
2
H
2
H
2
H CH
3
OH
2
O
C
(
s
)
Problem 5
– Vapor-Liquid Equilibrium • 40mole% Ethanol – water
Problem 6
• Liquid-Liquid Equilibria – Polar - polar
Problem 7
• Liquid-Liquid Equilibria – Polar - non-polar
Problem 8
• Multiple component phase equilibria – Methane – 0.1 mole fraction – Ethane – 0.2
– Propane- 0.3
– Butane- 0.3
– Methyl ethyl keytone -0.1
– 10 atm, 10°C – Use Ideal and Peng Robinson Thermo Pkg.
• Compare results
Example-9
• Distillation/Flash • Methanol – Water – 100 lbmole/hr • Flash at 90C, 1 atm • Distillation – R=2 – BoilUp Ratio=3