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| Introduction | |
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| A Process Control System | |
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| Important Terms and Objective of Automatic Process Control | |
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| Regulatory and Servo Control | |
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| Transmission Signals, Control Systems, and Other Terms | |
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| Control Strategies | |
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| Feedback Control | |
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| Feedforward Control | |
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| Background Needed for Process Control | |
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| Summary | |
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| Problems | |
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| Mathematical Tools for Control Systems Analysis | |
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| The Laplace Transform | |
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| Definition of the Laplace Transform | |
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| Properties of the Laplace Transform | |
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| Solution of Differential Equations Using the Laplace Transform | |
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| Laplace Transform Solution Procedure | |
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| Inversion by Partial Fractions Expansion | |
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| Handling Time Delays | |
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| Characterization of Process Response | |
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| Deviation Variables | |
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| Output Response | |
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| Stability | |
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| Response of First-Order Systems | |
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| Step Response | |
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| Ramp Response | |
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| Sinusoidal Response | |
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| Response with Time Delay | |
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| Response of a Lead-Lag Unit | |
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| Response of Second-Order Systems | |
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| Overdamped Responses | |
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| Underdamped Responses | |
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| Higher-Order Responses | |
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| Linearization | |
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| Linearization of Functions of One Variable | |
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| Linearization of Functions of Two or More Variables | |
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| Linearization of Differential Equations | |
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| Summary | |
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| Problems | |
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| First-Order Dynamic Systems | |
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| Processes and Importance of Process Characteristics | |
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| Mathematical Process Modeling | |
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| Thermal Process Example | |
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| Dead Time | |
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| Transfer Functions and Block Diagrams | |
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| Transfer Functions | |
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| Block Diagrams | |
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| Gas Process Example | |
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| Chemical Reactors | |
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| Introductory Remarks | |
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| Chemical Reactor Example | |
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| Effects of Process Nonlinearities | |
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| Additional Comments | |
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| Summary | |
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| Problems | |
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| Higher-Order Dynamic Systems | |
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| Noninteracting Systems | |
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| Noninteracting Level Process | |
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| Thermal Tanks in Series | |
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| Interacting Systems | |
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| Interacting Level Process | |
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| Thermal Tanks with Recycle | |
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| Nonisothermal Chemical Reaction | |
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| Response of Higher-Order Systems | |
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| Other Types of Process Responses | |
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| Integrating Processes: Level Process | |
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| Open-Loop Unstable Process: Chemical Reactor | |
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| Inverse Response Processes: Chemical Reactor | |
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| Summary | |
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| Overview of Chapters 3 and 4 | |
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| Problems | |
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| Basic Components of Control Systems | |
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| Sensors and Transmitters | |
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| Control Valves | |
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| The Control Valve Actuator | |
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| Control Valve Capacity and Sizing | |
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| Control Valve Characteristics | |
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| Control Valve Gain and Transfer Function | |
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| Control Valve Summary | |
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| Feedback Controllers | |
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| Actions of Controllers | |
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| Types of Feedback Controllers | |
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| Modifications to the PID Controller and Additional Comments | |
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| Reset Windup and Its Prevention | |
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| Feedback Controller Summary | |
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| Summary | |
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| Problems | |
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| Design of Single-Loop Process Control Systems | |
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| The Feedback Control Loop | |
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| Closed-Loop Transfer Function | |
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| Characteristic Equation of the Loop | |
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| Steady-State Closed-Loop Response | |
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| Stability of the Control Loop | |
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| Criterion of Stability | |
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| Direct Substitution Method | |
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| Effect of Loop Parameters on the Ultimate Gain and Period | |
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| Effect of Dead Time | |
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| Summary | |
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| Summary | |
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| Problems | |
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| Tuning of Feedback Controllers | |
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| Quarter Decay Ratio Response by Ultimate Gain | |
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| Open-Loop Process Characterization | |
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| Process Step Testing | |
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| Tuning for Quarter Decay Ratio Response | |
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| Tuning for Minimum Error Integral Criteria | |
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| Tuning Sampled-Data Controllers | |
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| Summary of Controller Tuning | |
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| Tuning Controllers for Integrating Processes | |
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| Model of Liquid Level Control System | |
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| Proportional Level Controller | |
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| Averaging Level Control | |
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| Summary of Tuning for Integrating Processes | |
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| Synthesis of Feedback Controllers | |
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| Development of the Controller Synthesis Formula | |
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| Specification of the Closed-Loop Response | |
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| Controller Modes and Tuning Parameters | |
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| Summary of Controller Synthesis Results | |
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| Tuning Rules by Internal Model Control (IMC) | |
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| Tips for Feedback Controller Tuning | |
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| Estimating the Reset and Rate Times | |
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| Adjusting the Proportional Gain | |
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| Summary | |
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| Problems | |
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| Root Locus and Frequency Response Techniques | |
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| Some Definitions | |
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| Analysis of Feedback Control Systems by Root Locus | |
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| Plotting Root Locus Diagrams | |
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| Analysis of Control Systems by Frequency Response | |
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| Bode Plots | |
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| Frequency Response Stability Criterion | |
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| Summary | |
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| Problems | |
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| Cascade Control | |
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| A Process Example | |
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| Stability Considerations | |
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| Implementation and Tuning of Controllers | |
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| Two-Level Cascade Systems | |
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| Three-Level Cascade Systems | |
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| Other Process Examples | |
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| Final Comments | |
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| Summary | |
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| Problems | |
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| Ratio, Override, and Selective Control | |
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| Signals, Software, and Computing Algorithms | |
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| Signals | |
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| Programming | |
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| Scaling Computing Algorithms | |
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| Ratio Control | |
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| Override, or Constraint, Control | |
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| Selective Control | |
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| Designing Control Systems | |
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| Summary | |
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| Problems | |
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| Feedforward Control | |
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| The Feedforward Concept | |
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| Block Diagram Design of Linear Feedforward Controllers | |
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| Lead-Lag Element | |
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| Back to the Previous Example | |
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| Design of Nonlinear Feedforward Controllers from Basic Process Principles | |
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| Some Closing Comments and Outline of Feedforward Controller Design | |
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| Three Other Examples | |
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| Summary | |
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| Problems | |
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| Multivariable Process Control | |
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| Loop Interaction | |
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| Pairing Controlled and Manipulated Variables | |
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| Calculating the Relative Gains for a 2 x 2 System | |
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| Calculating the Relative Gains for an n x n System | |
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| Decoupling of Interacting Loops | |
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| Decoupler Design from Block Diagrams | |
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| Decoupler Design for n x n Systems | |
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| Decoupler Design from Basic Principles | |
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| Multivariable Control versus Optimization | |
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| Dynamic Analysis of Multivariable Systems | |
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| Dynamic Analysis of a 2 x 2 System | |
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| Controller Tuning for Interacting Systems | |
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| Design of Plantwide Control Systems | |
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| Summary | |
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| Problems | |
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| Dynamic Simulation of Control Systems | |
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| Uses and Tools of Dynamic Simulation | |
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| Uses of Dynamic Simulation | |
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| Tools for Dynamic Simulation | |
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| Simulation of Linear Transfer Functions | |
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| Process Simulation | |
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| Simulation of Control Instrumentation | |
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| Control Valve Simulation | |
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| Simulation of Feedback Controllers | |
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| Simulation of Sensors-Transmitters | |
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| Simulation of Lead-Lag Dynamic Compensation | |
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| Other Simulation Aspects | |
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| Summary | |
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| Problems | |
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| Instrumentation Symbols and Labels | |
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| Design Case Studies | |
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| Methanol Synthesis Process | |
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| Hydrocarbon Process | |
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| Fatty Acid Process | |
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| Control Systems in the Sugar-Refining Process | |
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| Sulfuric Acid Process | |
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| Ammonium Nitrate Prilling Plant Control System | |
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| Natural Gas Dehydration Control System | |
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| Sensors, Transmitters, and Control Valves | |
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| Pressure Sensors | |
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| Flow Sensors | |
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| Level Sensors | |
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| Temperature Sensors | |
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| Composition Sensors | |
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| Transmitters | |
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| Pneumatic Transmitters | |
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| Electronic Transmitters | |
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| Types of Control Valves | |
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| Reciprocating Stem | |
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| Rotating Stem | |
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| Control Valve Actuators | |
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| Pneumatically Operated Diaphragm Actuators | |
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| Piston Actuators | |
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| Electrohydraulic and Electromechanical Actuators | |
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| Manual-Handwheel Actuators | |
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| Control Valve Accessories | |
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| Positioners | |
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| Boosters | |
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| Limit Switches | |
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| Control Valves-Additional Considerations | |
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| Viscosity Corrections | |
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| Flashing and Cavitation | |
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| Summary | |
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| Tuning Case Studies | |
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| Regenerator Feedback | |
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| Regenerator Cascade | |
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| Paper-Drying Process | |
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| HCl Scrubber | |
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| Mixing Process | |
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| Reactor Process | |
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| Distillation Process | |
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| Operating Case Studies | |
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| HCl Scrubber | |
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| Water Treatment unit | |
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| Catalyst Regenerator | |
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| Baby Back Ribs | |
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| Paper Drying Unit | |
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| Index | |