Chemical Process Design and Integration

Chemical Process Design and Integration

(Parte 1 de 8)

Chemical Process Design and Integration

Robin Smith

Centre for Process Integration,

School of Chemical Engineering and Analytical Science, University of Manchester.

Chemical Process Design and Integration Chemical Process Design and Integration

Chemical Process Design and Integration

Robin Smith

Centre for Process Integration,

School of Chemical Engineering and Analytical Science, University of Manchester.

Previous edition published by McGraw Hill

Copyright 2005 John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex PO19 8SQ, England

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Library of Congress Cataloging-in-Publication Data

Smith, R. (Robin)

Chemical process design and integration / Robin Smith. p. cm.

Includes bibliographical references and index.

British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library

ISBN 0-471-48680-9 (cloth) 0-471-48681-7 (paper)

Typeset in 10/12pt Times by Laserwords Private Limited, Chennai, India Printed and bound in Spain by Grafos, Barcelona This book is printed on acid-free paper responsibly manufactured from sustainable forestry in which at least two trees are planted for each one used for paper production.

To my family To my family

Contents

Preface xiii Acknowledgements xv Nomenclature xvii

Chapter1 TheN atureo f ChemicalP rocess Design and Integration 1

1.1 Chemical Products 1 1.2 Formulation of the Design Problem 3 1.3 Chemical Process Design and

Integration 4 1.4 The Hierarchy of Chemical Process

Design and Integration 5 1.5 Continuous and Batch Processes 9 1.6 New Design and Retrofit 10 1.7 Approaches to Chemical Process

Design and Integration 1 1.8 Process Control 13 1.9 The Nature of Chemical Process

Design and Integration – Summary 14 References 14

Chapter 2 Process Economics 17

2.1 The Role of Process Economics 17 2.2 Capital Cost for New Design 17 2.3 Capital Cost for Retrofit 23 2.4 Annualized Capital Cost 24 2.5 Operating Cost 25 2.6 Simple Economic Criteria 28 2.7 Project Cash Flow and Economic

Chapter 3 Optimization 35

3.1 Objective Functions 35 3.2 Single-variable Optimization 37 3.3 Multivariable Optimization 38 3.4 Constrained Optimization 42 3.5 Linear Programming 43

3.6 Nonlinear Programming 45 3.7 Profile Optimization 46 3.8 Structural Optimization 48 3.9 Solution of Equations using Optimization 52 3.10 The Search for Global

Chapter 4 Thermodynamic Properties and Phase Equilibrium 57

4.1 Equations of State 57 4.2 Phase Equilibrium for Single

Components 59 4.3 Fugacity and Phase Equilibrium 60 4.4 Vapor–Liquid Equilibrium 60 4.5 Vapor–Liquid Equilibrium Based on

Activity Coefficient Models 62 4.6 Vapor–Liquid Equilibrium Based on

Equations of State 64 4.7 Calculation of Vapor–Liquid

Equilibrium 64 4.8 Liquid–Liquid Equilibrium 70 4.9 Liquid–Liquid Equilibrium Activity

Coefficient Models 71 4.10 Calculation of Liquid–Liquid

Equilibrium 71 4.1 Calculation of Enthalpy 72 4.12 Calculation of Entropy 74 4.13 Phase Equilibrium and Thermodynamic

Chapter 5 Choice of Reactor I – Reactor Performance 7

5.1 Reaction Path 7 5.2 Types of Reaction Systems 78 5.3 Reactor Performance 81 5.4 Rate of Reaction 82 5.5 Idealized Reactor Models 83 5.6 Choice of Idealized Reactor Model 90 5.7 Choice of Reactor Performance 94 viii Contents

5.8 Choice of Reactor

Chapter 6 Choice of Reactor I - Reactor Conditions 97

Chapter 7 Choice of Reactor I – Reactor Configuration 121

7.1 Temperature Control 121 7.2 Catalyst Degradation 123 7.3 Gas–Liquid and Liquid–Liquid

Reactors 124 7.4 Reactor Configuration 127 7.5 Reactor Configuration for

Heterogeneous Solid-Catalyzed Reactions 133 7.6 Reactor Configuration from

Optimization of a Superstructure 133 7.7 Choice of Reactor

Chapter 8 Choice of Separator for Heterogeneous Mixtures 143

8.1 Homogeneous and Heterogeneous

Separation 143 8.2 Settling and Sedimentation 143 8.3 Inertial and Centrifugal Separation 147 8.4 Electrostatic Precipitation 149 8.5 Filtration 150 8.6 Scrubbing 151 8.7 Flotation 152 8.8 Drying 153 8.9 Separation of Heterogeneous

Chapter 9 Choice of Separator for

Homogeneous Fluid Mixtures I – Distillation 157

9.1 Single-Stage Separation 157 9.2 Distillation 157 9.3 Binary Distillation 160 9.4 Total and Minimum Reflux

Conditions for Multicomponent Mixtures 163 9.5 Finite Reflux Conditions for

Multicomponent Mixtures 170 9.6 Choice of Operating Conditions 175 9.7 Limitations of Distillation 176 9.8 Separation of Homogeneous Fluid

Mixtures by Distillation – Summary 177 9.9 Exercises 178 References 179

Chapter 10 Choice of Separator for

Homogeneous Fluid Mixtures I – Other Methods 181

10.1 Absorption and Stripping 181 10.2 Liquid–Liquid Extraction 184 10.3 Adsorption 189 10.4 Membranes 193 10.5 Crystallization 203 10.6 Evaporation 206 10.7 Separation of Homogeneous Fluid

Mixtures by Other Methods – Summary 208 10.8 Exercises 209 References 209

Chapter 1 Distillation Sequencing 21

1.1 Distillation Sequencing Using

Simple Columns 211 1.2 Practical Constraints Restricting

Options 211 1.3 Choice of Sequence for Simple

Nonintegrated Distillation Columns 212 1.4 Distillation Sequencing Using

Columns With More Than Two Products 217 1.5 Distillation Sequencing Using

Thermal Coupling 220 1.6 Retrofit of Distillation Sequences 224 1.7 Crude Oil Distillation 225 1.8 Distillation Sequencing Using

Optimization of a Superstructure 228 1.9 Distillation Sequencing – Summary 230 1.10 Exercises 231 References 232

Contents ix

Chapter 12 Distillation Sequencing for Azeotropic Distillation 235

12.1 Azeotropic Systems 235 12.2 Change in Pressure 235 12.3 Representation of Azeotropic

Distillation 236 12.4 Distillation at Total Reflux

Conditions 238 12.5 Distillation at Minimum Reflux

Conditions 242 12.6 Distillation at Finite Reflux

Conditions 243 12.7 Distillation Sequencing Using an

Entrainer 246 12.8 Heterogeneous Azeotropic

Distillation 251 12.9 Entrainer Selection 253 12.10 Trade-offs in Azeotropic Distillation 255 12.1 Multicomponent Systems 255 12.12 Membrane Separation 255 12.13 Distillation Sequencing for

Azeotropic Distillation – Summary 256 12.14 Exercises 257 References 258

Chapter 13 Reaction, Separation and Recycle Systems for Continuous Processes 259

13.1 The Function of Process Recycles 259 13.2 Recycles with Purges 264 13.3 Pumping and Compression 267 13.4 Simulation of Recycles 276 13.5 The Process Yield 280 13.6 Optimization of Reactor Conversion 281 13.7 Optimization of Processes Involving a Purge 283 13.8 Hybrid Reaction and Separation 284 13.9 Feed, Product and Intermediate

Storage 286 13.10 Reaction, Separation and Recycle

Systems for Continuous Processes – Summary 288 13.1 Exercises 289 References 290

Chapter 14 Reaction, Separation and Recycle Systems for Batch Processes 291

14.1 Batch Processes 291 14.2 Batch Reactors 291 14.3 Batch Separation Processes 297 14.4 Gantt Charts 303 14.5 Production Schedules for Single Products 304

14.6 Production Schedules for Multiple

Products 305 14.7 Equipment Cleaning and Material

Transfer 306 14.8 Synthesis of Reaction and

Separation Systems for Batch Processes 307 14.9 Optimization of Batch Processes 311 14.10 Storage in Batch Processes 312 14.1 Reaction and Separation Systems for

Batch Processes – Summary 313 14.12 Exercises 313 References 315

Chapter 15 Heat Exchanger Networks I – Heat Transfer Equipment 317

15.1 Overall Heat Transfer Coefficients 317 15.2 Heat Transfer Coefficients and

Pressure Drops for Shell-and-Tube Heat Exchangers 319 15.3 Temperature Differences in

Shell-and-Tube Heat Exchangers 324 15.4 Allocation of Fluids in

Shell-and-Tube Heat Exchangers 329 15.5 Extended Surface Tubes 332 15.6 Retrofit of Heat Exchangers 3 15.7 Condensers 337 15.8 Reboilers and Vaporizers 342 15.9 Other Types of Heat Exchange

Chapter 16 Heat Exchanger Networks I – Energy Targets 357

16.1 Composite Curves 357 16.2 The Heat Recovery Pinch 361 16.3 Threshold Problems 364 16.4 The Problem Table Algorithm 365 16.5 Nonglobal Minimum Temperature

Differences 370 16.6 Process Constraints 370 16.7 Utility Selection 372 16.8 Furnaces 374 16.9 Cogeneration (Combined Heat and

Power Generation) 376 16.10 Integration Of Heat Pumps 381 16.1 Heat Exchanger Network Energy Targets – Summary 383 x Contents

Chapter 17 Heat Exchanger Networks

I – Capital and Total Cost Targets 387

17.1 Number of Heat Exchange Units 387 17.2 Heat Exchange Area Targets 388 17.3 Number-of-shells Target 392 17.4 Capital Cost Targets 393 17.5 Total Cost Targets 395 17.6 Heat Exchanger Network and

Utilities Capital and Total Costs – Summary 395 17.7 Exercises 396 References 397

Chapter 18 Heat Exchanger Networks IV – Network Design 399

18.1 The Pinch Design Method 399 18.2 Design for Threshold Problems 404 18.3 Stream Splitting 405 18.4 Design for Multiple Pinches 408 18.5 Remaining Problem Analysis 411 18.6 Network Optimization 413 18.7 The Superstructure Approach to

Heat Exchanger Network Design 416 18.8 Retrofit of Heat Exchanger

Networks 419 18.9 Addition of New Heat Transfer Area in Retrofit 424 18.10 Heat Exchanger Network

Chapter 19 Heat Exchanger Networks V – Stream Data 429

19.1 Process Changes for Heat

Integration 429 19.2 The Trade-Offs Between Process

Changes, Utility Selection, Energy Cost and Capital Cost 429 19.3 Data Extraction 430 19.4 Heat Exchanger Network Stream

Chapter 20 Heat Integration of Reactors 439

20.1 The Heat Integration Characteristics of Reactors 439 20.2 Appropriate Placement of Reactors 441 20.3 Use of the Grand Composite Curve for Heat Integration of Reactors 442 20.4 Evolving Reactor Design to Improve

Heat Integration 443 20.5 Heat Integration of

Chapter 21 Heat Integration of Distillation Columns 445

21.1 The Heat Integration Characteristics of Distillation 445 21.2 The Appropriate Placement of

Distillation 445 21.3 Use of the Grand Composite Curve for Heat Integration of Distillation 446 21.4 Evolving the Design of Simple

Distillation Columns to Improve Heat Integration 447 21.5 Heat Pumping in Distillation 449 21.6 Capital Cost Considerations 449 21.7 Heat Integration Characteristics of

Distillation Sequences 450 21.8 Heat-integrated Distillation

Sequences Based on the Optimization of a Superstructure 454 21.9 Heat Integration of Distillation

Chapter 2 Heat Integration of Evaporators and Dryers 459

2.1 The Heat Integration Characteristics of Evaporators 459 2.2 Appropriate Placement of

Evaporators 459 2.3 Evolving Evaporator Design to

Improve Heat Integration 459 2.4 The Heat Integration Characteristics of Dryers 459 2.5 Evolving Dryer Design to Improve

Heat Integration 460 2.6 Heat Integration of Evaporators and Dryers – Summary 461

Contents xi

Chapter 23 Steam Systems and Cogeneration 465

23.1 Boiler Feedwater Treatment 466 23.2 Steam Boilers 468 23.3 Steam Turbines 471 23.4 Gas Turbines 477 23.5 Steam System Configuration 482 23.6 Steam and Power Balances 484 23.7 Site Composite Curves 487 23.8 Cogeneration Targets 490 23.9 Optimization of Steam Levels 493 23.10 Site Power-to-heat Ratio 496 23.1 Optimizing Steam Systems 498 23.12 Steam Costs 502 23.13 Choice of Driver 506 23.14 Steam Systems and

Chapter 24 Cooling and Refrigeration Systems 513

24.1 Cooling Systems 513 24.2 Recirculating Cooling Water

Systems 513 24.3 Targeting Minimum Cooling Water

Flowrate 516 24.4 Design of Cooling Water Networks 518 24.5 Retrofit of Cooling Water Systems 524 24.6 Refrigeration Cycles 526 24.7 Process Expanders 530 24.8 Choice of Refrigerant for

Compression Refrigeration 532 24.9 Targeting Refrigeration Power for

Compression Refrigeration 535 24.10 Heat Integration of Compression

Refrigeration Processes 539 24.1 Mixed Refrigerants for Compression

Refrigeration 542 24.12 Absorption Refrigeration 544 24.13 Indirect Refrigeration 546 24.14 Cooling Water and Refrigeration

Chapter 25 Environmental Design for Atmospheric Emissions 551

25.1 Atmospheric Pollution 551

25.2 Sources of Atmospheric Pollution 552 25.3 Control of Solid Particulate

Emissions to Atmosphere 553 25.4 Control of VOC Emissions to

Atmosphere 554 25.5 Control of Sulfur Emissions 565 25.6 Control of Oxides of Nitrogen

Emissions 569 25.7 Control of Combustion Emissions 573 25.8 Atmospheric Dispersion 574 25.9 Environmental Design for

Chapter 26 Water System Design 581

26.1 Aqueous Contamination 583 26.2 Primary Treatment Processes 585 26.3 Biological Treatment Processes 588 26.4 Tertiary Treatment Processes 591 26.5 Water Use 593 26.6 Targeting Maximum Water Reuse for Single Contaminants 594 26.7 Design for Maximum Water Reuse for Single Contaminants 596 26.8 Targeting and Design for Maximum

Water Reuse Based on Optimization of a Superstructure 604 26.9 Process Changes for Reduced Water

Consumption 606 26.10 Targeting Minimum Wastewater

Treatment Flowrate for Single Contaminants 607 26.1 Design for Minimum Wastewater

Treatment Flowrate for Single Contaminants 610 26.12 Regeneration of Wastewater 613 26.13 Targeting and Design for Effluent

(Parte 1 de 8)

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