Chemical Engineering Design Principles, Practice and Economics of Plant and Process Design Second Edition Gavin Towler Ray Sinnott AMSTERDAM • BOSTON • HEIDELBERG • LONDON NEW YORK • OXFORD • PARIS • SAN DIEGO SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO Butterworth-Heinemann is an imprint of Elsevier Butterworth-Heinemann is an imprint of Elsevier The Boulevard, Langford Lane, Kidlington, Oxford, OX5 1GB, UK 225 Wyman Street, Waltham, MA 02451, USA © 2013 Elsevier Ltd All rights reserved No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the Publisher Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein) Notices Knowledge and best practice in this field are constantly changing As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein Library of Congress Cataloging-in-Publication Data Towler, Gavin P Chemical engineering design : principles, practice, and economics of plant and process design / Gavin Towler, Ray Sinnott – 2nd ed p cm ISBN 978-0-08-096659-5 (hardback) Chemical engineering I Sinnott, R K II Title TP155.T69 2012 660.068'5–dc23 2011044962 British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library For information on all Butterworth-Heinemann publications visit our website at www.elsevierdirect.com Typeset by: diacriTech, Chennai, India Printed in the United States of America 12 13 14 15 10 Contents Preface to the Second Edition xi How to Use This Book xiii Acknowledgments xv PART PROCESS DESIGN CHAPTER Introduction to Design 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Introduction Nature of Design The Organization of a Chemical Engineering Project Project Documentation 12 Codes and Standards 18 Design Factors (Design Margins) 20 Systems of Units 20 Product Design 22 References 31 Nomenclature 31 Problems 31 CHAPTER Process Flowsheet Development 33 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 Introduction 33 Flowsheet Presentation 34 The Anatomy of a Chemical Manufacturing Process 45 Selection, Modification, and Improvement of Commercially-Proven Processes 57 Revamps of Existing Plants 64 Synthesis of Novel Flowsheets 78 PFD Review 91 Overall Procedure for Flowsheet Development 95 References 96 Nomenclature 98 Problems 98 CHAPTER Utilities and Energy Efficient Design 103 3.1 3.2 3.3 3.4 3.5 3.6 Introduction 103 Utilities 104 Energy Recovery 117 Waste Stream Combustion 123 Heat-exchanger Networks 126 Energy Management in Unsteady Processes 149 iii iv Contents References 155 Nomenclature 157 Problems 158 CHAPTER Process Simulation 161 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 Introduction 161 Process Simulation Programs 162 Specification of Components 165 Selection of Physical Property Models 169 Simulation of Unit Operations 184 User Models 219 Flowsheets With Recycle 223 Flowsheet Optimization 236 Dynamic Simulation 239 References 239 Nomenclature 241 Problems 243 CHAPTER Instrumentation and Process Control 251 5.1 5.2 5.3 5.4 5.5 5.6 5.7 Introduction 251 The P&I Diagram 252 Process Instrumentation and Control 257 Conventional Control Schemes 261 Alarms, Safety Trips, and Interlocks 270 Batch Process Control 272 Computer Control Systems 272 References 275 Problems 276 CHAPTER Materials of Construction 279 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 6.10 6.11 6.12 Introduction 279 Material Properties 280 Mechanical Properties 280 Corrosion Resistance 283 Selection for Corrosion Resistance 288 Material Costs 289 Contamination 290 Commonly Used Materials of Construction 291 Plastics as Materials of Construction for Chemical Plant 297 Ceramic Materials (Silicate Materials) 300 Carbon 301 Protective Coatings 302 Contents v 6.13 Design for Corrosion Resistance 302 References 302 Nomenclature 304 Problems 304 CHAPTER Capital Cost Estimating 307 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9 7.10 7.11 Introduction 307 Components of Capital Cost 308 Accuracy and Purpose of Capital Cost Estimates 311 Order of Magnitude Estimates 312 Estimating Purchased Equipment Costs 320 Estimating Installed Costs: The Factorial Method 328 Cost Escalation 335 Location Factors 338 Estimating Offsite Capital Costs 340 Computer Tools for Cost Estimating 341 Validity of Cost Estimates 348 References 349 Nomenclature 350 Problems 352 CHAPTER Estimating Revenues and Production Costs 355 8.1 8.2 8.3 8.4 8.5 8.6 Introduction 355 Costs, Revenues, and Profits 356 Product and Raw Material Prices 360 Estimating Variable Production Costs 373 Estimating Fixed Production Costs 376 Summarizing Revenues and Production Costs 380 References 385 Nomenclature 385 Problems 385 CHAPTER Economic Evaluation of Projects 389 9.1 9.2 9.3 9.4 9.5 9.6 9.7 Introduction 389 Cash Flows during a Project 389 Project Financing 393 Taxes and Depreciation 398 Simple Methods for Economic Analysis 403 Present Value Methods 406 Annualized Cost Methods 411 vi Contents 9.8 Sensitivity Analysis 414 9.9 Project Portfolio Selection 421 References 426 Nomenclature 426 Problems 427 CHAPTER 10 Safety and Loss Prevention 431 10.1 10.2 10.3 10.4 10.5 10.6 10.7 10.8 10.9 Introduction 431 Materials Hazards 436 Process Hazards 443 Analysis of Product and Process Safety 450 Failure-Mode Effect Analysis 454 Safety Indices 456 Hazard and Operability Studies 467 Quantitative Hazard Analysis 475 Pressure Relief 481 References 496 Nomenclature 501 Problems 502 CHAPTER 11 General Site Considerations 505 11.1 11.2 11.3 11.4 11.5 Introduction 505 Plant Location and Site Selection 505 Site Layout 508 Plant Layout 509 Environmental Considerations 513 References 522 CHAPTER 12 Optimization in Design 525 12.1 12.2 12.3 12.4 12.5 12.6 12.7 12.8 12.9 Introduction 525 The Design Objective 526 Constraints and Degrees of Freedom 527 Trade-Offs 530 Problem Decomposition 531 Optimization of a Single Decision Variable 532 Search Methods 533 Optimization of Two or More Decision Variables 536 Linear Programming 539 Contents vii 12.10 Nonlinear Programming 540 12.11 Mixed Integer Programming 542 12.12 Optimization in Industrial Practice 544 References 549 Nomenclature 549 Problems 551 PART PLANT DESIGN CHAPTER 13 Equipment Selection, Specification, and Design 557 13.1 Introduction 557 13.2 Sources of Equipment Design Information 558 13.3 Guide to Equipment Selection and Design 560 References 562 CHAPTER 14 Design of Pressure Vessels 563 14.1 14.2 14.3 14.4 14.5 14.6 14.7 14.8 14.9 14.10 14.11 14.12 14.13 14.14 14.15 Introduction 563 Pressure Vessel Codes and Standards 565 Fundamentals of Strength of Materials 567 General Design Considerations for Pressure Vessels 570 The Design of Thin-Walled Vessels Under Internal Pressure 575 Compensation for Openings and Branches 584 Design of Vessels Subject to External Pressure 584 Design of Vessels Subject to Combined Loading 585 Vessel Supports 598 Bolted Flanged Joints 606 Welded Joint Design 615 Fatigue Assessment of Vessels 617 Pressure Tests 618 High-Pressure Vessels 618 Liquid Storage Tanks 621 References 622 Nomenclature 624 Problems 627 CHAPTER 15 Design of Reactors and Mixers 631 15.1 Introduction 631 15.2 Reactor Design: General Procedure 632 15.3 Sources of Reaction Engineering Data 641 viii Contents 15.4 15.5 15.6 15.7 15.8 15.9 15.10 15.11 15.12 15.13 15.14 Choice of Reaction Conditions 653 Mixing 660 Heating and Cooling of Reacting Systems 669 Multiphase Reactors 678 Reactor Design for Catalytic Processes 689 Design of Bioreactors 712 Multifunctional Batch Reactors 733 Computer Simulation of Reactors 735 Determining Actual Reactor Performance 738 Safety Considerations in Reactor Design 740 Capital Cost of Reactors 744 References 744 Nomenclature 747 Problems 750 CHAPTER 16 Separation of Fluids 753 16.1 16.2 16.3 16.4 16.5 Introduction 753 Gas-Gas Separations 754 Gas–Liquid Separators 768 Liquid-Liquid Separation 773 Separation of Dissolved Components 780 References 801 Nomenclature 803 Problems 805 CHAPTER 17 Separation Columns (Distillation, Absorption, and Extraction) 807 17.1 17.2 17.3 17.4 17.5 17.6 17.7 17.8 17.9 17.10 17.11 Introduction 807 Continuous Distillation: Process Description 808 Continuous Distillation: Basic Principles 811 Design Variables in Distillation 816 Design Methods for Binary Systems 817 Multicomponent Distillation: General Considerations 824 Multicomponent Distillation: Shortcut Methods for Stage and Reflux Requirements 833 Multicomponent Distillation: Rigorous Solution Procedures (Computer Methods) 839 Other Distillation Processes 841 Plate Efficiency 843 Approximate Column Sizing 853 Contents 17.12 17.13 17.14 17.15 17.16 17.17 ix Plate Contactors 854 Plate Hydraulic Design 863 Packed Columns 886 Column Auxiliaries 916 Solvent Extraction (Liquid–Liquid Extraction) 917 Capital Cost of Separation Columns 923 References 924 Nomenclature 928 Problems 932 CHAPTER 18 Specification and Design of Solids-Handling Equipment 937 18.1 18.2 18.3 18.4 18.5 18.6 18.7 18.8 18.9 18.10 18.11 Introduction 937 Properties of Granular Materials 938 Storage and Transport of Solids 952 Separation and Mixing of Solids 966 Gas-Solids Separations (Gas Cleaning) 975 Separation of Solids from Liquids 987 Separation of Liquids from Solids (Drying) 1008 Solids Formation, Shaping, and Size Enlargement Processes 1021 Particle Size Reduction (Comminution) 1026 Heat Transfer to Flowing Solid Particles 1034 Hazards of Solids Processing 1035 References 1037 Nomenclature 1042 Problems 1045 CHAPTER 19 Heat-Transfer Equipment 1047 19.1 19.2 19.3 19.4 19.5 19.6 19.7 19.8 19.9 19.10 19.11 19.12 19.13 Introduction 1047 Basic Design Procedure and Theory 1048 Overall Heat-Transfer Coefficient 1050 Fouling Factors (Dirt Factors) 1053 Shell and Tube Exchangers: Construction Details 1054 Mean Temperature Difference (Temperature Driving Force) 1069 Shell and Tube Exchangers: General Design Considerations 1074 Tube-Side Heat-Transfer Coefficient and Pressure Drop (Single Phase) 1077 Shell-Side Heat Transfer and Pressure Drop (Single Phase) 1083 Condensers 1107 Reboilers and Vaporizers 1130 Plate Heat Exchangers 1156 Direct-Contact Heat Exchangers 1165 APPENDIX G EQUIPMENT SPECIFICATION (DATA) SHEETS G-13 G-14 APPENDIX G EQUIPMENT SPECIFICATION (DATA) SHEETS H TYPICAL SHELL AND TUBE HEAT EXCHANGER TUBE-SHEET LAYOUTS (a) Fixed tube-sheet exchanger (b) U-tube exchanger (c) Floating-head exchanger with split backing ring (d) Pull through floating-head exchanger Reproduced with permission from Heat Exchanger Design, E A D Saunders (Longman Group) H-1 H-2 APPENDIX H TYPICAL SHELL AND TUBE HEAT EXCHANGER TUBE-SHEET LAYOUTS (a) Typical tube layout for a fixed tubesheet exchanger 740 i/Dia shell, single pass, 780-tubes, 19.05 o/Dia on 23.8125 pitch, 308 angle APPENDIX H TYPICAL SHELL AND TUBE HEAT EXCHANGER TUBE-SHEET LAYOUTS H-3 (b) Typical tube layout for a U-tube exchanger 740 i/Dia shell, 2-pass, 246 U-tubes, 19.05 o/Dia on 25.4 pitch, 458 angle H-4 APPENDIX H TYPICAL SHELL AND TUBE HEAT EXCHANGER TUBE-SHEET LAYOUTS (c) Typical tube layout for a split backing ring floating-head exchanger 740 i/Dia shell, 6-pass, 580 tubes, 19.05 o/Dia on 25.4 pitch, 308 angle Denotes 13 Dia sealing bars APPENDIX H TYPICAL SHELL AND TUBE HEAT EXCHANGER TUBE-SHEET LAYOUTS H-5 (d) Typical tube layout for a pull-through floating-head exchanger 740 i/Dia shell, 4-pass, 370 tubes 19.05 o/Dia on 25.4 pitch, 908 angle Denotes 13 Dia sealing bars I MATERIAL SAFETY DATA SHEET 1,2-DICHLOROETHANE, EXTRA DRY, WATER < 50 PPM ACC# 00220 Reproduced with permission of Fischer Acros Inc SECTION 1—CHEMICAL PRODUCT AND COMPANY IDENTIFICATION MSDS Name: 1,2-Dichloroethane, extra dry, water 99.9 203-458-1 Hazard Symbols: T F Risk Phrases: 11 22 36/37/38 45 I-1 I-2 APPENDIX I MATERIAL SAFETY DATA SHEET SECTION 3—HAZARDS IDENTIFICATION EMERGENCY OVERVIEW Appearance: colorless liquid Flash Point: 56 deg F Warning! Flammable liquid and vapor May cause central nervous system depression May cause liver and kidney damage May cause cancer based on animal studies Causes eye and skin irritation Causes respiratory tract irritation Irritant May be harmful if swallowed Target Organs: Central nervous system, liver, eyes, skin Potential Health Effects Eye: Causes eye irritation Vapors may cause eye irritation May cause chemical conjunctivitis and corneal damage Skin: Causes skin irritation May be absorbed through the skin May cause irritation and dermatitis May cause cyanosis of the extremities Ingestion: May cause central nervous system depression, kidney damage, and liver damage May cause gastrointestinal irritation with nausea, vomiting, and diarrhea May cause effects similar to those for inhalation exposure May be harmful if swallowed Inhalation: Inhalation of high concentrations may cause central nervous system effects characterized by nausea, headache, dizziness, unconsciousness, and coma Causes respiratory tract irritation May cause liver and kidney damage Aspiration may lead to pulmonary edema Vapors may cause dizziness or suffocation Can produce delayed pulmonary edema Exposure to high concentrations may produce narcosis, nausea, and loss of consciousness May cause burning sensation in the chest Chronic: Possible cancer hazard based on tests with laboratory animals Prolonged or repeated skin contact may cause dermatitis Prolonged or repeated eye contact may cause conjunctivitis May cause liver and kidney damage Effects may be delayed SECTION 4—FIRST AID MEASURES Eyes: Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids Get medical aid Skin: Get medical aid Flush skin with plenty of water for at least 15 minutes while removing contaminated clothing and shoes Wash clothing before reuse Ingestion: Never give anything by mouth to an unconscious person Get medical aid Do NOT induce vomiting If conscious and alert, rinse mouth and drink 2–4 cupfuls of milk or water Inhalation: Remove from exposure and move to fresh air immediately If not breathing, give artificial respiration If breathing is difficult, give oxygen Get medical aid Do NOT use mouth-to-mouth resuscitation Notes to Physician: Treat symptomatically and supportively APPENDIX I MATERIAL SAFETY DATA SHEET I-3 SECTION 5—FIRE FIGHTING MEASURES General Information: As in any fire, wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear Vapors may form an explosive mixture with air During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion Use water spray to keep fire-exposed containers cool Flammable liquid and vapor Approach fire from upwind to avoid hazardous vapors and toxic decomposition products Vapors are heavier than air and may travel to a source of ignition and flash back Vapors can spread along the ground and collect in low or confined areas Extinguishing Media: For small fires, use dry chemical, carbon dioxide, water spray, or alcohol-resistant foam For large fires, use water spray, fog, or alcohol-resistant foam Water may be ineffective Do NOT use straight streams of water Flash Point: 56 deg F ( 13.33 deg C) Autoignition Temperature: 775 deg F ( 412.78 deg C) Explosion Limits, Lower: 6.2% Upper: 15.9% NFPA Rating: (estimated) Health: 2; Flammability: 3; Instability: SECTION 6—ACCIDENTAL RELEASE MEASURES General Information: Use proper personal protective equipment as indicated in Section Spills/Leaks: Absorb spill with inert material (e.g., vermiculite, sand, or earth), then place in suitable container Avoid runoff into storm sewers and ditches which lead to waterways Clean up spills immediately, observing precautions in the Protective Equipment section Remove all sources of ignition Use a spark-proof tool Provide ventilation A vapor-suppressing foam may be used to reduce vapors SECTION 7—HANDLING AND STORAGE Handling: Wash thoroughly after handling Remove contaminated clothing and wash before reuse Ground and bond containers when transferring material Use sparkproof tools and explosion-proof equipment Avoid contact with eyes, skin, and clothing Empty containers retain product residue (liquid and/or vapor) and can be dangerous Keep container tightly closed Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks, or open flames Use only with adequate ventilation Keep away from heat, sparks, and flame Avoid breathing vapor or mist Storage: Keep away from heat, sparks, and flame Keep away from sources of ignition Store in a tightly closed container Keep from contact with oxidizing materials Store in a cool, dry, well-ventilated area away from incompatible I-4 APPENDIX I MATERIAL SAFETY DATA SHEET substances Flammables-area Storage under a nitrogen blanket has been recommended SECTION 8—EXPOSURE CONTROLS, PERSONAL PROTECTION Engineering Controls: Facilities storing or utilizing this material should be equipped with an eyewash facility and a safety shower Use adequate general or local explosion-proof ventilation to keep airborne levels to acceptable levels Exposure Limits Chemical Name ACGIH NIOSH OSHA—Final PELs 1,2-Dichloroethane 10 ppm TWA ppm TWA; mg/m3 TWA 50 ppm IDLH 50 ppm TWA; 100 ppm Ceiling OSHA Vacated PELs: 1,2-Dichloroethane: ppm TWA; mg/m3 TWA Personal Protective Equipment Eyes: Wear chemical goggles Skin: Wear appropriate protective gloves to prevent skin exposure Clothing: Wear appropriate protective clothing to prevent skin exposure Respirators: A respiratory protection program that meets OSHA’s 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator’s use SECTION 9—PHYSICAL AND CHEMICAL PROPERTIES Physical State: Liquid Appearance: colorless Odor: chloroform-like pH: Not available Vapor Pressure: 100 mm Hg @29 deg C Vapor Density: 3.4 (Air¼1) Evaporation Rate:6.5 (Butyl acetate¼1) Viscosity: Not available Boiling Point: 81–85 deg C Freezing/Melting Point: À35 deg C Decomposition Temperature: Not available Solubility: Insoluble Specific Gravity/Density:1.25 (Water¼1) Molecular Formula: C2H4Cl2 Molecular Weight: 98.96 APPENDIX I MATERIAL SAFETY DATA SHEET I-5 SECTION 10—STABILITY AND REACTIVITY Chemical Stability: Stable at room temperature in closed containers under normal storage and handling conditions Conditions to Avoid: Light, ignition sources, excess heat, electrical sparks Incompatibilities with Other Materials: Aluminum, bases, alkali metals, ketones, organic peroxides, nitric acid, strong oxidizing agents, strong reducing agents, liquid ammonia, amines Hazardous Decomposition Products: Hydrogen chloride, phosgene, carbon monoxide, irritating and toxic fumes and gases, carbon dioxide Hazardous Polymerization: Has not been reported SECTION 11—TOXICOLOGICAL INFORMATION RTECS#: CAS# 107-06-2: KI0525000 LD50/LC50: CAS# 107-06-2: Draize test, rabbit, eye: 63 mg Severe; Draize test, rabbit, eye: 500 mg/24H Mild; Draize test, rabbit, skin: 500 mg/24H Mild; Inhalation, rat: LC50 ¼ 1000 ppm/7H; Oral, mouse: LD50 ¼ 413 mg/kg; Oral, rabbit: LD50 ¼ 860 mg/kg; Oral, rat: LD50 ¼ 670 mg/kg; Skin, rabbit: LD50 ¼ 2800 mg/kg;