A Real-Time Approach to Process Control

With resources at a premium, and ecological concerns paramount, the need for clean, efficient and low–cost processes is one of the most critical challenges facing chemical engineers. The ability to control these processes, optimizing one, two or several variables has the potential to make more substantial savings in time, money and resources than any other single factor.    Building on the success of the previous editions, this new third edition of A Real–Time Approach to Process Control employs both real industry practice and process control education without the use of complex or highly mathematical techniques, providing a more practical and applied approach. Updated throughout, this edition: •             Includes a brand new chapter on Model predictive Control (MPC) •             Now includes wireless and web–based technologies •             Covers bio–related systems •             Details the new multivariable control measure developed by the authors •             Includes PowerPoint slides and solutions to Workshop problems on the accompanying website: http://www.wiley.com/go/svrcek–real–time–3e   From the reviews of previous editions: “Would appeal to practising engineers due to its “hands on” feel for the subject matter. But more importantly, the authors present these concepts as fundamentals of chemical engineering, in a way that is consistent with how professor teach at the universities.” –Chemical Engineering Process (CEP) “The book has been beautifully crafted” –Engineering Subject Centre “Provides a refreshing approach to the presentation of process analysis and control”  –The Chemical Engineer INDICE: Author Biographies xi Foreword and Endorsements xiii Preface xv Acknowledgements xvii 1 A Brief History of Process Control and Process Simulation 1 1.1 Process Control 1 1.2 Process Simulation 5 References 11 2 Process Control Hardware Fundamentals 15 2.1 Control System Components 15 2.2 Primary Elements 16 2.2.1 Pressure Measurement 17 2.2.2 Level Measurement 21 2.2.3 Temperature Measurement 23 2.2.4 Flow Measurement 26 2.2.5 Quality Measurement and Analytical Instrumentation 32 2.2.6 Application Range and Accuracy of Different Sensors 33 2.3 Final Control Elements 33 2.3.1 Control Valves 33 References 53 3 Fundamentals of Single–Input/Single–Output Systems 55 3.1 Open Loop Control 55 3.2 Disturbances 56 3.3 Feedback Control – Overview 57 3.4 Feedback Control – A Closer Look 60 3.4.1 Positive and Negative Feedbacks 60 3.4.2 Control Elements 60 3.4.3 Sensor/Transmitter 63 3.4.4 Processes 63 3.4.5 Final Control Element 65 3.4.6 Controller 65 3.5 Process Attributes – Capacitance and Dead Time 66 3.5.1 Capacitance 67 3.5.2 Dead Time 71 3.6 Process Dynamic Response 74 3.7 Process Modelling and Simulation 76 3.7.1 First–Order Systems 76 3.7.2 Second–Order and Higher Order Systems 76 3.7.3 Simple System Analysis 83 3.7.4 Classical Modelling for Control Approaches 89 3.7.5 The Modern Modelling for Control Approach 92 References 93 4 Basic Control Modes 95 4.1 On–Off Control 95 4.2 Proportional (P–Only) Control 97 4.3 Integral (I–Only) Control 102 4.4 Proportional Plus Integral (PI) Control 105 4.5 Derivative Action 107 4.6 Proportional Plus Derivative (PD) Controller 108 4.7 Proportional Integral Derivative (PID) Control 111 4.8 Digital Electronic Controller Forms 112 4.9 Choosing the Correct Controller 112 4.10 Controller Hardware 114 References 117 5 Tuning Feedback Controllers 119 5.1 Quality of Control and Optimization 119 5.1.1 Controller Response 120 5.1.2 Error Performance Criteria 122 5.2 Tuning Methods 123 5.2.1 ‘Trial and Error’ Method 124 5.2.2 Process Reaction Curve Methods 125 5.2.3 Constant Cycling Methods 127 References 132 6 Advanced Topics in Classical Automatic Control 133 6.1 Cascade Control 133 6.1.1 Starting up a Cascade System 136 6.2 Feedforward Control 137 6.3 Ratio Control 140 6.4 Override Control (Auto Selectors) 142 6.4.1 Protection of Equipment 143 6.4.2 Auctioneering 145 6.4.3 Redundant Instrumentation 145 6.4.4 Artificial Measurements 147 6.5 Split Range Control 147 References 149 7 Common Control Loops 151 7.1 Flow Loops 151 7.2 Liquid Pressure Loops 153 7.3 Liquid Level Control 155 7.3.1 Proportional–Only Control for Integrating Processes 163 7.3.2 PI Controller Tuning for Integrating Process 164 7.4 Gas Pressure Loops 165 7.5 Temperature Control Loops 166 7.5.1 The Endothermic Reactor Temperature Control Loop 168 7.5.2 The Exothermic Reactor Temperature Control Loop 170 7.6 Pump Control 172 7.7 Compressor Control 172 7.7.1 Reciprocating Compressor Control 173 7.7.2 Centrifugal Compressor Control 173 7.8 Boiler Control 179 7.8.1 Combustion Control 180 7.8.2 Water Drum Level Control 181 7.8.3 Water Drum Pressure Control 181 7.8.4 Steam Temperature Control 181 References 182 8 Distillation Column Control 185 8.1 Basic Terms 185 8.2 Steady–State and Dynamic Degrees of Freedom 186 8.3 Control System Objectives and Design Considerations 188 8.4 Methodology for Selection of a Controller Structure 190 8.5 Level, Pressure, Temperature and Composition Control 192 8.5.1 Level Control 192 8.5.2 Pressure Control 193 8.5.3 Temperature Control 198 8.5.4 Composition Control 198 8.6 Optimizing Control 199 8.6.1 Example: Benzene Column with a Rectifying Section Sidestream 199 8.7 Distillation Control Scheme Design Using Steady–State Models 204 8.7.1 Screening Control Strategies via Steady–State Simulation 206 8.7.2 A Case Study – The Workshop Stabilizer 207 8.7.3 Respecifying Simulation Specifications 207 8.7.4 Mimicking the Behaviour of Analysers or Lab Analyses 209 8.7.5 Developing an Economic Profitability Function 209 8.7.6 Evaluating the Candidate Strategies 210 8.7.7 Evaluating the Candidate Strategies under Disturbances 211 8.7.8 Evaluating Sensor Strategies 211 8.7.9 Example Summary 212 8.8 Distillation Control Scheme Design Using Dynamic Models 212 References 213 9 Using Steady–State Methods in a Multi–loop Control Scheme 215 9.1 Variable Pairing 215 9.2 The Relative Gain Array 216 9.2.1 Calculating the RGA with Experiments 216 9.2.2 Calculating the RGA Using the Steady–State Gain Matrix 218 9.2.3 Interpreting the RGA 219 9.3 Niederlinski Index 220 9.4 Decoupling Control Loops 220 9.4.1 Singular Value Decomposition 221 9.5 Tuning the Controllers for Multi–loop Systems 222 9.6 Practical Examples 222 9.6.1 Example 1: A Two–Stream Mixer 222 9.6.2 Example 2: A Conventional Distillation Column 226 9.7 Summary 232 References 232 10 Plant–Wide Control 233 10.1 Short–Term versus Long–Term Control Focus 233 10.2 Cascaded Units 235 10.3 Recycle Streams 236 10.4 General Considerations for Plant–Wide Control 241 References 242 11 Advanced Process Control 245 11.1 Advanced Process Control 245 11.2 Model Predictive Control 246 11.3 Dynamic Matrix Control 249 11.4 General Considerations for Model Predictive Control Implementation 253 References 254 Appendix A P&ID Symbols 257 Appendix B Glossary of Terms 261 Appendix C New Capabilities with Control Technology Hardware and Software 267 Workshop 1 Learning through Doing 279 Workshop 2 Feedback Control Loop Concepts 283 Workshop 3 Process Capacity and Dead Time 289 Workshop 4 Feedback Control 295 Workshop 5 Controller Tuning for Capacity and Dead Time Processes 303 Workshop 6 Topics in Advanced Control 311 Workshop 7 Distillation Control 321 Workshop 8 Plant Operability and Controllability 333 Index

• ISBN: 978-1-119-99388-9
• Editorial: Wiley–Blackwell
• Encuadernacion: Rústica
• Páginas: 360
• Fecha Publicación: 24/01/2014
• Nº Volúmenes: 1
• Idioma: Inglés