460 likes | 532 Views
This paper presents a comprehensive overview of the design and optimization of azeotropic separation systems. It addresses problem challenges, related research issues, and solution approaches, focusing on multi-feed compositions, flowrates, and azeotropes. The study includes simulation, economics, approximation techniques, and the use of asynchronous teams for efficient design processes.
E N D
MULTIPERIOD DESIGN OFAZEOTROPIC SEPARATIONSYSTEMS Kenneth H. Tyner and Arthur W. Westerberg
OVERVIEW • Problem Description • Problem Challenges • Related Research Issues • Solution Approach • Conclusions
F1 F2 PROBLEM DESCRIPTION B • Design An Optimal Separation Plant • Multiple Feeds • Flowrate • Composition • Operating Time • Azeotropes F3 A Az C
F1 F2 PROBLEM DESCRIPTION B A C F B Az F3 A Az C
F1 F2 PROBLEM DESCRIPTION B A C F B F3 A Az C
PROBLEM DESCRIPTION FEED 1 FEED 2 FEED 3
PROBLEM DESCRIPTION FEED 1 FEED 2 FEED 3
PROBLEM DESCRIPTION FEED 1 FEED 2 FEED 3
PROBLEM DESCRIPTION FEED 1 FEED 2 FEED 3
PROBLEM CHALLENGES • Highly Combinatorial • Separation Pathways • Process Units • Task Assignment • Difficult Subproblems • Large Models • Highly Nonlinear • Recycle Streams • Shared Equipment
INITIAL RESEARCH THRUSTS • Synthesize Designs • Evaluate Designs • Optimize / Modify Designs
AZEOTROPIC SYNTHESIS B A C F B Az F A Az C
AZEOTROPIC SYNTHESIS B A C F B Az F A Az C
AZEOTROPIC SYNTHESIS B A C F B F A Az C
S S S Slack Zero SIMULATION
Solve / Optimize Library Initialize SIMULATION Modify
REVISED RESEARCH THRUSTS • Collocation Error Detection • Scaling • Solver Design
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 Column Design and Operation Contributions
F TASK APPROXIMATION B • Variables: • Compositions • Flowrates • Relations: • Mass Balance • Lever Rule • Geometric Objects B D A Az C
F D / F TASK APPROXIMATION B • Variables: • Compositions • Flowrates • Relations: • Mass Balance • Lever Rule • Geometric Objects B D A Az C
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)
Numerical Difficulties COLUMN APPROXIMATION • Gilliland Correlation • Reflux = C1 * exp(-C2 * Trays) + C3 • Opt Feed Loc = C4 * Trays + C5
DATA COLLECTION • Fix Trays and Task • Find Optimal Reflux
Calculate Parameters Store In Database DATA COLLECTION B A Az C
F Database SIMULATION A C B F B Az A Az C
F Database SIMULATION A C B F B Az A Az C
Slack Zero SIMULATION S S S
Newton Solver Gradient Solver Trial Points ASYNCHRONOUS TEAMS • Independent Software Agents • Shared Memory
ASYNCHRONOUS TEAMS • Independent Software Agents • Shared Memory Newton Solver Gradient Solver Trial Points
ASYNCHRONOUS TEAMS • Independent Software Agents • Shared Memory Newton Solver Gradient Solver Trial Points
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 Approximation Agents Database Approximation Data Problem Description Designs Design 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
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
GENERAL BENEFITS • Alternative to Hierarchical Design • Persistent Data • Scenario Analysis • Human Agents