Separation Process Engineering: Includes Mass Transfer Analysis

The Definitive, Up-to-Date, Student-Friendly Guide to Separation Process Engineering—With More Mass Transfer Coverage and a New Chapter on Crystallization   Separation Process Engineering, Fourth Edition, is the most comprehensive, accessible guide available on modern separation processes and the fundamentals of mass transfer. In this completely updated edition, Phillip C. Wankat teaches each key concept through detailed, realistic examples using real data—including up-to-date simulation practice and spreadsheet-based exercises.   Wankat thoroughly covers each separation process, including flash, column, and batch distillation; exact calculations and shortcut methods for multicomponent distillation; staged and packed column design; absorption; stripping; and more. This edition provides expanded coverage of mass transfer and diffusion, so faculty can cover separations and mass transfer in one course.   Detailed discussions of liquid-liquid extraction, adsorption, chromatography, and ion exchange prepare students for advanced work. Wankat presents coverage of membrane separations, including gas permeation, reverse osmosis, ultrafiltration, pervaporation, and applications. An updated chapter on economics and energy conservation in distillation adds coverage of equipment costs.   This edition contains more than 300 new, up-to-date homework problems, extensively tested in undergraduate courses at Purdue University and the University of Canterbury (New Zealand).   Coverage includes New chapter on crystallization from solution, including equilibrium, chemical purity, crystal size distribution, and pharmaceutical applications Thirteen up-to-date Aspen Plus process simulation labs, adaptable to any simulator Eight detailed Aspen Chromatography labs Extensive new coverage of ternary stage-by-stage distillation calculations Fraction collection and multicomponent calculations for simple batch distillation New mass transfer analysis sections on numerical solution for variable diffusivity Mass transfer to expanding or contracting objects, including ternary mass transfer Expanded coverage of pervaporation Updated Excel spreadsheets offering more practice with distillation, diffusion, mass transfer, and membrane separation problems

Table of Contents:
Preface xix Acknowledgments xxi About the Author xxiii Nomenclature xxv   Chapter 1: Introduction to Separation Process Engineering 1 1.0. Summary—Objectives 1 1.1. Importance of Separations 1 1.2. Concept of Equilibrium 3 1.3. Mass Transfer Concepts 4 1.4. Problem-Solving Methods 5 1.5. Units 7 1.6. Computers and Computer Simulations 8 1.7. Prerequisite Material 8 1.8. Other Resources on Separation Process Engineering 9 References 11 Homework 12   Chapter 2: Flash Distillation 15 2.0. Summary—Objectives 15 2.1. Basic Method of Flash Distillation 15 2.2. Form and Sources of Equilibrium Data 17 2.3. Graphical Representation of Binary VLE 20 2.4. Binary Flash Distillation 25 2.5. Multicomponent VLE 32 2.6. Multicomponent Flash Distillation 36 2.7. Simultaneous Multicomponent Convergence 42 2.8. Three-Phase Flash Calculations 47 2.9. Size Calculation 48 2.10. Using Existing Flash Drums 53 References 54 Homework 55 Appendix A. Computer Simulation of Flash Distillation 67 Appendix B. Spreadsheets for Flash Distillation 77   Chapter 3: Introduction to Column Distillation 81 3.0. Summary—Objectives 81 3.1. Developing a Distillation Cascade 82 3.2. Distillation Equipment 88 3.3. Specifications 90 3.4. External Column Balances 94 References 98 Homework 98   Chapter 4: Binary Column Distillation: Internal Stage-by-Stage Balances 105 4.0. Summary—Objectives 105 4.1. Internal Balances 106 4.2. Binary Stage-by-Stage Solution Methods 110 4.3. Introduction to the McCabe-Thiele Method 116 4.4. Feed Line 120 4.5. Complete McCabe-Thiele Method 128 4.6. Profiles for Binary Distillation 132 4.7. Open Steam Heating 132 4.8. General McCabe-Thiele Analysis Procedure 138 4.9. Other Distillation Column Situations 146 4.10. Limiting Operating Conditions 151 4.11. Efficiencies 154 4.12. Simulation Problems 156 4.13. New Uses for Old Columns 158 4.14. Subcooled Reflux and Superheated Boilup 159 4.15. Comparisons Between Analytical and Graphical Methods 161 References 162 Homework 163 Appendix A. Computer Simulation of Binary Distillation 179 Appendix B. Spreadsheets for Binary Distillation 183   Chapter 5: Introduction to Multicomponent Distillation 189 5.0. Summary—Objectives 189 5.1. Calculational Difficulties 189 5.2. Profiles for Multicomponent Distillation 194 5.3. Stage-by-Stage Calculations for CMO 199 References 206 Homework 206 Appendix A. Simplified Spreadsheet for Stage-by-Stage Calculations for Ternary Distillation 212 Appendix B. Automated Spreadsheet with VBA for Stage-by-Stage Calculations for Ternary Distillation 215   Chapter 6 Exact Calculation Procedures for Multicomponent Distillation 219 6.0. Summary—Objectives 219 6.1. Introduction to Matrix Solution for Multicomponent Distillation 219 6.2. Component Mass Balances in Matrix Form 221 6.3. Initial Guesses for Flow Rates and Temperatures 225 6.4. Temperature Convergence 225 6.5. Energy Balances in Matrix Form 229 6.6. Introduction to Naphtali-Sandholm Simultaneous Convergence Method 232 6.7. Discussion 233 References 234 Homework 235 Appendix. Computer Simulations for Multicomponent Column Distillation 241   Chapter 7: Approximate Shortcut Methods for Multicomponent Distillation 249 7.0. Summary—Objectives 249 7.1. Total Reflux: Fenske Equation 250 7.2. Minimum Reflux: Underwood Equations 254 7.3. Gilliland Correlation for Number of Stages at Finite Reflux Ratios 259 References 263 Homework 263   Chapter 8: Introduction to Complex Distillation Methods 271 8.0. Summary—Objectives 271 8.1. Breaking Azeotropes with Other Separators 272 8.2. Binary Heterogeneous Azeotropic Distillation Processes 273 8.3. Steam Distillation 282 8.4. Pressure-Swing Distillation Processes 286 8.5. Complex Ternary Distillation Systems 287 8.6. Extractive Distillation 296 8.7. Azeotropic Distillation with Added Solvent 302 8.8. Distillation with Chemical Reaction 306 References 309 Homework 310 Appendix A. Simulation of Complex Distillation Systems 326 Appendix B. Spreadsheet for Residue Curve Generation 336   Chapter 9: Batch Distillation 339 9.0. Summary—Objectives 339 9.1. Introduction to Batch Distillation 339 9.2. Batch Distillation: Rayleigh Equation 341 9.3. Simple Binary Batch Distillation 344 9.4. Constant-Mole Batch Distillation 349 9.5. Batch Steam Distillation 350 9.6. Multistage Binary Batch Distillation 352 9.7. Multicomponent Simple Batch Distillation 357 9.8. Operating Time 361 References 362 Homework 363 Appendix A. Spreadsheet for Simple Multicomponent Batch Distillation, Constant Relative Volatility 372   Chapter 10: Staged and Packed Column Design 375 10.0. Summary—Objectives 375 10.1. Staged Column Equipment Description 376 10.2. Tray Efficiencies 385 10.3. Column Diameter Calculations 390 10.4. Balancing Calculated Diameters 396 10.5. Sieve Tray Layout and Tray Hydraulics 398 10.6. Valve Tray Design 404 10.7. Introduction to Packed Column Design 406 10.8. Packings and Packed Column Internals 406 10.9. Height of Packing: HETP Method 409 10.10. Packed Column Flooding and Diameter Calculation 411 10.11. Economic Trade-Offs for Packed Columns 417 10.12. Choice of Column Type 418 References 421 Homework 425 Appendix. Tray and Downcomer Design with Computer Simulator 433   Chapter 11: Economics and Energy Conservation in Distillation 437 11.0. Summary—Objectives 437 11.1. Equipment Costs 438 11.2. Basic Heat Exchanger Design 443 11.3. Design and Operating Effects on Costs 445 11.4. Changes in Plant Operating Rates 454 11.5. Energy Conservation in Distillation 455 11.6. Synthesis of Column Sequences for Almost Ideal Multicomponent Distillation 460 11.7. Synthesis of Distillation Systems for Nonideal Ternary Systems 466 References 470 Homework 472   Chapter 12: Absorption and Stripping 481 12.0. Summary—Objectives 482 12.1. Absorption and Stripping Equilibria 483 12.2. McCabe-Thiele Solution for Dilute Absorption 485 12.3. Stripping Analysis for Dilute Systems 489 12.4. Analytical Solution for Dilute Systems: Kremser Equation 490 12.5. Efficiencies 496 12.6. McCabe-Thiele Analysis for More Concentrated Systems 497 12.7. Column Diameter 501 12.8. Dilute Multisolute Absorbers and Strippers 502 12.9. Matrix Solution for Concentrated Absorbers and Strippers 504 12.10. Irreversible Absorption and Cocurrent Cascades 508 References 510 Homework 511 Appendix. Computer Simulations of Absorption and Stripping 520   Chapter 13: Liquid-Liquid Extraction 527 13.0. Summary—Objectives 527 13.1. Extraction Processes and Equipment 527 13.2. Dilute, Immiscible, Countercurrent Extraction 532 13.3. Dilute Fractional Extraction 539 13.4. Immiscible Single-Stage and Cross-Flow Extraction 543 13.5. Concentrated Immiscible Extraction 547 13.6. Immiscible Batch Extraction 551 13.7. Extraction Equilibrium for Partially Miscible Ternary Systems 553 13.8. Mixing Calculations and the Lever-Arm Rule 556 13.9. Partially Miscible Single-Stage and Cross-Flow Systems 558 13.10. Countercurrent Extraction Cascades for Partially Miscible Systems 561 13.11. Relationship Between McCabe-Thiele and Triangular Diagrams for Partially Miscible Systems 569 13.12. Minimum Solvent Rate for partially Miscible Systems 570 13.13. Extraction Computer Simulations 572 13.14. Design of Mixer-Settlers 573 References 586 Homework 588 Appendix. Computer Simulation of Extraction 598   Chapter 14: Washing, Leaching, and Supercritical Extraction 603 14.0. Summary—Objectives 603 14.1. Generalized McCabe-Thiele and Kremser Procedures 603 14.2. Washing 606 14.3. Leaching with Constant Flow Rates 610 14.4. Leaching with Variable Flow Rates 612 14.5. Introduction to Supercritical Fluid Extraction 615 14.6. Application of McCabe-Thiele and Kremser Methods to Other Separations 617 References 618 Homework 619   Chapter 15: Introduction to Diffusion and Mass Transfer 627 15.0. Summary–Objectives 629 15.1. Molecular Movement Leads to Mass Transfer 629 15.2. Fickian Model of Diffusivity 631 15.3. Values and Correlations for Fickian Binary Diffusivities 647 15.4. Linear Driving-Force Model of Mass Transfer for Binary Systems 656 15.5. Correlations for Mass Transfer Coefficients 670 15.6. Difficulties with Fickian Diffusion Model 682 15.7. Maxwell-Stefan Model of Diffusion and Mass Transfer 683 15.8. Advantages and Disadvantages of Different Diffusion and Mass Transfer Models 698 References 698 Homework 700 Appendix. Spreadsheets Examples 15-10 and 15-11 707   Chapter 16: Mass Transfer Analysis for Distillation, Absorption, Stripping, and Extraction 711 16.0. Summary—Objectives 711 16.1. HTU-NTU Analysis of Packed Distillation Columns 712 16.2. Relationship of HETP and HTU 720 16.3. Mass Transfer Correlations for Packed Towers 723 16.4. HTU-NTU Analysis of Concentrated Absorbers and Strippers 731 16.5. HTU-NTU Analysis of Cocurrent Absorbers 736 16.6. Prediction of Distillation Tray Efficiency 738 16.7. Mass Transfer Analysis of Extraction 741 16.8. Rate-Based Analysis of Distillation 753 References 756 Homework 758 Appendix. Computer Rate-Based Simulation of Distillation 765   Chapter 17: Crystallization from Solution 769 17.0. Summary–Objectives 769 17.1. Basic Principles of Crystallization from Solution 770 17.2. Continuous Cooling Crystallizers 776 17.3. Evaporative and Vacuum Crystallizers 785 17.4. Sieve Analysis 793 17.5. Introduction to Population Balances 798 17.6. Crystal Size Distributions for MSMPR Crystallizers 800 17.7 Seeding 814 17.8. Batch and Semibatch Crystallization 820 17.9. Precipitation 825 References 828 Homework 830 Appendix. Spreadsheets 836   Chapter 18: Introduction to Membrane Separation Processes 837 18.0. Summary—Objectives 838 18.1. Membrane Separation Equipment 840 18.2. Membrane Concepts 843 18.3. Gas Permeation 845 18.4. Reverse Osmosis (RO) 862 18.5. Ultrafiltration (UF) 877 18.6. Pervaporation (Pervap) 883 18.7. Bulk Flow Pattern Effects 895 References 899 Homework 901 Appendix. Spreadsheet for Crossflow Gas Permeation 914   Chapter 19: Introduction to Adsorption, Chromatography, and Ion Exchange 917 19.0. Summary—Objectives 918 19.1. Sorbents and Sorption Equilibrium 918 19.2. Solute Movement Analysis for Linear Systems: Basics and Applications to Chromatography 930 19.3. Solute Movement Analysis for Linear Systems: Temperature and Pressure Swing Adsorption and Simulated Moving Beds 938 19.4. Nonlinear Solute Movement Analysis 961 19.5. Ion Exchange 970 19.6. Mass and Energy Transfer in Packed Beds 978 19.7. Mass Transfer Solutions for Linear Systems 985 19.8. LUB Approach for Nonlinear Sorption Systems 993 19.9. Checklist for Practical Design and Operation 998 References 1000 Homework 1003 Appendix. Aspen Chromatography Simulator 1019   Appendix A: Aspen Plus Troubleshooting Guide for Separations 1047   Appendix B: Instructions for Fitting VLE and LLE Data with Aspen Plus 1051   Appendix C: Unit Conversions and Physical Constants 1053   Appendix D: Data Locations 1055   Answers to Selected Problems 1065   Index 1073