Plantwide Control of Chemical Processes

Overview

Contents:
Essentials of Process Control : Process dynamics, Laplace transform models and identification - Concept of feedback control, block diagram representation, PID control algorithm and tuning - Multivariable control: Niederlinski Index, Relative Gain Array, SVD - Decoupling, Decentralized controller tuning, dynamic matrix control - Advanced control structures: Feedforward control, ratio control, cascade control, override control and optimizing control.

Control Structures for Common Unit Operations :
Control structures for simple distillation columns: LV, LB, DV, DB. Single ended and dual ended temperature inferential control, criteria for temperature control tray selection.

Control of complex column configurations: Side draw columns, side rectifier/side stripper columns, heat integrated columns - Petlyuk and Kaibel columns, homogenous and heterogenous azeotropic distillation - Reactive distillation, Do's and dont's of distillation control - CSTR control: Reaction heat removal and corresponding control schemes.
Multiple steady states and stability analysis, heat integration - PBR control: Adiabatic operation, Reaction heat removal schemes and control structures, heat integration - Control of heat exchangers - Control of miscellaneous operations: Compressors, furnaces, refrigeration systems, boiler systems, decanters.

Plant-wide Control Fundamentals : Degrees of freedom: control dof, steady state performance dof, dynamic dof - Rigorous dof analysis for example processes - Simple dof calculation procedure, Equivalence of control structures and steady state dof specs - Plant-wide implications of material (energy) recycle:The snowball effect, effect on process time constant, component inventory balancing - Through-put manipulation and its relation to local inventory control loops - Consistent and inconsistent control structures for a simple recycle process - Plant-wide regulatory Control Structure Design Case Studies:Recycle process with side reaction, cumene manufacture process, hydrodealkylation of toluene, vinyl chloride process.

Plant-wide Control for Improved Economics : Process operation for a given throughput and for maximum throughput - The concept of a bottleneck constraint - Application of optimizing controllers for throughput maximization on case-study processes - Considerations in plant-wide control structure design for throughput maximization:Throughput manipulator, inventory loop tuning, plant-wide propagation of process variablility - Recycle process plant-wide control design case-study:Economic operation for given throughput and for maximum throughput - Control system design for multiple active constraints - Systematic approaches for plant-wide control system design:Luyben's bottom-up design approachand Skogestads top-down optimization based approach. Example case-studies.