MULTIPERIOD DESIGN OF AZEOTROPIC SEPARATION SYSTEMS Kenneth H. Tyner and Arthur W. Westerberg
OVERVIEW Problem Description Problem Challenges Previous Work Related Research Issues Solution Approach Conclusions
PROBLEM DESCRIPTION Design An Optimal Separation Plant Multiple Feeds –Flowrate –Composition –Operating Time Azeotropes A B CAz F1 F3 F2
PROBLEM DESCRIPTION A B CAz F1 F3 F2 F A B C Az
PROBLEM DESCRIPTION A B CAz F1 F3 F2 F A B C
PROBLEM DESCRIPTION FEED 1FEED 3FEED 2
PROBLEM DESCRIPTION FEED 1FEED 3FEED 2
PROBLEM DESCRIPTION FEED 1FEED 3FEED 2
PROBLEM DESCRIPTION FEED 1FEED 3FEED 2
PROBLEM DESCRIPTION FEED 1FEED 3FEED 2
PROBLEM CHALLENGES Highly Combinatorial –Separation Pathways –Process Units –Task Assignment Difficult Subproblems –Large Models –Highly Nonlinear –Recycle Streams –Shared Equipment
MULTIPERIOD DESIGN Constraints: –Column Dimensions –Heat Exchanger Dimensions –Flooding Conditions
MULTIPERIOD DESIGN Collocation Models: –Number of Trays and Feed Location Variable –Variable Transformations
MULTIPERIOD DESIGN
EXTEND TO AZEOTROPIC MULTIPERIOD DESIGN? Additional Feasibility Constraints How Many Columns? Large Number of Simulations Stream Characteristics Change
INITIAL RESEARCH THRUSTS Synthesize Designs Evaluate Designs Optimize / Modify Designs
AZEOTROPIC SYNTHESIS A B CAz F F A B C
AZEOTROPIC SYNTHESIS A B CAz F A B C F
AZEOTROPIC SYNTHESIS A B CAz F F A B C
SIMULATION Zero Slack S S S
SIMULATION Solve / Optimize Initialize Modify Library
REVISED RESEARCH THRUSTS Collocation Error Detection Scaling Solver Design
SIMULATION Solve / Optimize Initialize Modify Library
SOLUTION APPROACH Approximation –Separation Task –Column Design and Operation Shortcut Costing Autonomous Agents
ECONOMICS Cost = F( Feed, Distillate, Trays, Reflux )
ECONOMICS Cost = F( Feed, Distillate, Trays, Reflux ) Separation Task Contribution
ECONOMICS Cost = F( Feed, Distillate, Trays, Reflux ) Separation Task Contribution Column Design and Operation Contributions
TASK APPROXIMATION Variables: –Compositions –Flowrates Relations: –Mass Balance –Lever Rule –Geometric Objects A B CAz F D / F D B
COLUMN APPROXIMATION Cost = F(Feed, Distillate, Trays, Reflux) Reflux = F(Trays, Feed Location)
COLUMN APPROXIMATION Cost = F(Feed, Distillate, Trays, Reflux) Reflux = F(Trays) Optimal Feed Location = F(Trays)
COLUMN APPROXIMATION Reflux = C 1 * exp(-C 2 * Trays) + C 3 Opt Feed Loc = C 4 * Trays + C 5 –Numerical Difficulties Gilliland Correlation
DATA COLLECTION Fix Trays and Task Find Optimal Reflux
DATA COLLECTION
A B CAz Store In Database Calculate Parameters
SIMULATION F A B C Az A B C F Database
SIMULATION F A B C Az A B C F Database
SIMULATION Zero Slack S S S
ASYNCHRONOUS TEAMS Independent Software Agents Shared Memory Trial Points Newton SolverGradient Solver
ASYNCHRONOUS TEAMS Independent Software Agents Shared Memory Trial Points Newton SolverGradient Solver
ASYNCHRONOUS TEAMS Independent Software Agents Shared Memory Trial Points Newton SolverGradient Solver
ASYNCHRONOUS TEAMS Independent Software Agents Shared Memory Trial Points Newton SolverGradient Solver
ASYNCHRONOUS TEAMS Independent Software Agents Shared Memory Advantages –Scalable –Ease of Creation / Maintenance –Cooperation
ASYNCHRONOUS TEAMS Applications –Train Scheduling –Travelling Salesman Problem –Building Design
ASYNCHRONOUS TEAMS Problem Description Approximation Data Designs Database Design Agents Approximation Agents
MINLP DESIGN AGENT Fixed: –Separation Pathways –Intermediate Streams Variable: –Task Assignment –Number of Columns –Column Dimensions –Operating Policy
MINLP DESIGN AGENT Fixed: –Separation Pathways –Intermediate Streams Variable: –Task Assignment –Number of Columns –Column Dimensions –Operating Policy
MINLP DESIGN AGENT Fixed: –Separation Pathways –Intermediate Streams Variable: –Task Assignment –Number of Columns –Column Dimensions –Operating Policy
TASK ASSIGNMENT
PATH SELECTION Sequential Selection Genetic Algorithm Active Constraint
MINLP DESIGN AGENT Fixed: –Separation Pathways –Intermediate Streams Variable: –Task Assignment –Number of Columns –Column Dimensions –Operating Policy
ASYNCHRONOUS TEAMS Problem Description Approximation Data Designs Database Design Agents Approximation Agents
GENERAL BENEFITS Alternative to Hierarchical Design Persistent Data Scenario Analysis Human Agents
MULTIPERIOD DESIGN OF AZEOTROPIC SEPARATION SYSTEMS Kenneth H. Tyner and Arthur W. Westerberg