aspen tutorial - university of utahring/design i/lecture_… · ppt file · web view ·...
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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
Towler and Sinnott , “Chemical Engineering Design : Principles , Practice, Economics of Plant and Process Design” , Elsevier (2008)
**
* - Reaction Engineering, Mass Transfer, Heat Transfer, Fluid Mechanics
Numerical Methods
Thermodynamics
Thermodynamics
Other Subjects : Solid Mechanics, Manufacturing ScienceEconomics
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?
Eric Carlson’s Recommendations
E?
R?
P?
Polar
Real
Electrolyte
Pseudo & Real
Vacuum
Non-electrolyte
Braun K-10 or ideal
Chao-Seader,Grayson-Streed or Braun K-10
Peng-Robinson,Redlich-Kwong-Soave,Lee-Kesler-Plocker
Electrolyte NRTLOr Pizer
See Figure 2Figure 1
Polarity
R? Real or pseudocomponents
P? Pressure
E? Electrolytes
All Non-polar
P?
ij?
ij?
LL?
(See alsoFigure 3)
P < 10 bar
P > 10 barPSRKPR or SRK with MHV2
Schwartentruber-RenonPR or SRK with WSPR or SRK with MHV2
UNIFAC and its extensions
UNIFAC LLE
PolarNon-electrolytes
No
Yes
Yes
LL?No
No
Yes
Yes
NoWILSON, NRTL,UNIQUAC and their variances
NRTL, UNIQUACand their variances
LL? Liquid/Liquid
P? Pressure
ij? Interaction Parameters Available
Figure 2
VAP?
DP?Yes
No Wilson, NRTL,UNIQUAC, or UNIFAC* with ideal Gas or RK EOS
Wilson NRTLUNIQUACUNIFAC
Hexamers
Dimers Wilson, NRTL, UNIQUAC, UNIFAC with Hayden O’Connell or Northnagel EOS
Wilson, NRTL, UNIQUAC, or UNIFAC with special EOS for Hexamers
VAP? Vapor Phase Association
Degrees of PolymerizatiomDP?UNIFAC* and its Extensions
Figure 3
Bob Seader’s Recommendations
LG?
E?
PC?
HC?
Yes
Yes
No
Yes
See Figure 5
Special: e.g., Sour Water (NH3, CO2, H2S, H2O) Aqueous amine solution with CO2 and H2S
PC?
No
Modified NRTLNo
No
PSRKYes
No See Figure 5See Figure 6
HC? Hydrocarbons
LG? Light gases
PC? Organic Polar Compound
E? Electrolyte
Yes
Figure 4
Figure 5
T?
P?
BP?
Narrow or wide
PR
LKP
Cryogenic
Non- Cryogenic
Critical
Non-Critical
SRK, PR
PR, BWRS
Very wide
HC and/ or LG
P? Pressure region
T? Temperature region
BP? Boiling point range of compound
Figure 6
PPS?
BIP?
Available
UNIFAC
Yes
No Wilson
NRTL, UNIQUAC
Not Available
PC with HC
PPS?Possible PhaseSplitting
BIP? Binary Interaction Parameters
Model Pure Binary Mixture VLE VLLE Notes
EOS (Equation of State)
SRK (Soave RedlichKwong) ● ● ● ● ●
Gas Processing with No Methanol, Refinery Distillation
Peng-Robinson● ● ● ● ●
Gas Processing with No Methanol
SRK Polar● ● ● ● ●
Gas Processing with Methanol or NMP
Peng-Robinson Polar ● ● ● ● ●
Gas Processing with Methanol or NMP
Lee-Kesler
● ● ● ● Light Hydrocarbon Systems with H2S and CO2, No 2nd Liquid Phase
Tillner-Roth and Friend NH3 + H2O
● ● ●
Ammonia Absorption Refrigeration, Ammonia and/or Water Only
ProMax Guidance(5 more pages like this)
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 To, Po to Tf, Pf
– STATE PROPERTY• 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 Minimization reactor in Aspen to determine the products of reaction at 10 atm and 200 C.
• Feed equimolar in CO and H2
)(2
22
32
sCOHHCOOHCHHCO
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
• Use sensitivity analysis to determine reactor conversion at a suite of temperatures
OHCHHCO 322
Problem -4
• Determine the resulting equilibrium at 10 atm and 200 C using an equilibrium reactor in Aspen with both of the reactions listed.
)(2
22
32
sCOHHCOOHCHHCO
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