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 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 Telephone (+44) 1243 779777 Email (for orders and customer service enquiries): cs-books@wiley.co.uk Visit our Home Page on www.wileyeurope.com or www.wiley.com All Rights Reserved. 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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. ISBN 0-471-48680-9 (HB) (acid-free paper) – ISBN 0-471-48681-7 (PB) (pbk. : acid-free paper) 1. Chemic al processes. I. Title. TP155.7.S573 2005 660  .2812 – dc22 2004014695 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 Contents Preface xiii Acknowledgements xv Nomenclature xvii Chapter1 TheNatureofChemicalProcess 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 11 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 Evaluation 29 2.8 Investment Criteria 30 2.9 Process Economics – Summary 31 2.10 Exercises 32 References 33 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 Optimality 53 3.11 Summary – Optimization 54 3.12 Exercises 54 References 56 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 4.11 Calculation of Enthalpy 72 4.12 Calculation of Entropy 74 4.13 Phase Equilibrium and Thermodynamic Properties – Summary 74 4.14 Exercises 74 References 76 Chapter 5 Choice of Reactor I – Reactor Performance 77 5.1 Reaction Path 77 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 Performance – Summary 94 5.9 Exercises 95 References 96 Chapter 6 Choice of Reactor II - Reactor Conditions 97 6.1 Reaction Equilibrium 97 6.2 Reactor Temperature 100 6.3 Reactor Pressure 107 6.4 Reactor Phase 108 6.5 Reactor Concentration 109 6.6 Biochemical Reactions 114 6.7 Catalysts 114 6.8 Choice of Reactor Conditions – Summary 117 6.9 Exercises 118 References 120 Chapter 7 Choice of Reactor III – 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 Configuration – Summary 139 7.8 Exercises 139 References 140 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 Mixtures – Summary 154 8.10 Exercises 154 References 155 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 II – 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 11 Distillation Sequencing 211 11.1 Distillation Sequencing Using Simple Columns 211 11.2 Practical Constraints Restricting Options 211 11.3 Choice of Sequence for Simple Nonintegrated Distillation Columns 212 11.4 Distillation Sequencing Using Columns With More Than Two Products 217 11.5 Distillation Sequencing Using Thermal Coupling 220 11.6 Retrofit of Distillation Sequences 224 11.7 Crude Oil Distillation 225 11.8 Distillation Sequencing Using Optimization of a Superstructure 228 11.9 Distillation Sequencing – Summary 230 11.10 Exercises 231 References 232 [...]... deals with the design and integration of chemical processes, emphasizing the conceptual issues that are fundamental to the creation of the process Chemical process design requires the selection of a series of processing steps and their integration to form a complete manufacturing system The text emphasizes both the design and selection of the steps as individual operations and their integration to... derivation of the design equations has been included in the text The book is intended to provide a practical guide to chemical process design and integration for undergraduate and postgraduate students of chemical engineering, practicing process designers and chemical engineers and applied chemists working in process development For undergraduate studies, the text assumes basic knowledge of material and energy... plant not working Too much overdesign will lead to the plant becoming unnecessarily expensive, and perhaps difficult to operate and less efficient A balance must be made between different risks Consider the basic features of the design of chemical processes now 1.3 CHEMICAL PROCESS DESIGN AND INTEGRATION In a chemical process, the transformation of raw materials into desired chemical products usually cannot... system follows the reactor design The reactor and separation and recycle system designs together define the process for heating and cooling duties The Hierarchy of Chemical Process Design and Integration 7 FEED CW FEED Steam Reactor PRODUCT CW Steam Steam BYPRODUCT (a) FEED CW FEED Steam Reactor CW PRODUCT Steam Steam BYPRODUCT (b) Figure 1.4 For a given reactor and separator design there are different... for small-scale processes If a batch process manufactures only a single product, then the equipment can be designed and optimized for REACTOR Steam Cooling Water Feed Storage Product Storage Steam Figure 1.8 A simple batch process Cooling Water 10 The Nature of Chemical Process Design and Integration that product The dynamic nature of the process creates additional challenges for design and optimization... in process design are likely to differ significantly, depending on whether a process is being designed for the manufacture of a commodity, fine or specialty chemical In commodity chemicals, there is likely to be relatively little product innovation, but intensive process innovation Also, equipment will be designed for a specific process step On the other hand, the manufacture of fine and specialty chemicals... environmentally harmful, and solid waste to landfill must be avoided Finally, all aspects of chemical processing must feature good health and safety practice It is important for the designer to understand the limitations of the methods used in chemical process design The best way to understand the limitations is to understand the derivations of the equations used and the assumptions on which the equations... Chapter 28 Clean Process Technology 28.1 Sources of Waste from Chemical Production 28.2 Clean Process Technology for Chemical Reactors 28.3 Clean Process Technology for Separation and Recycle Systems 28.4 Clean Process Technology for Process Operations 28.5 Clean Process Technology for Utility Systems 28.6 Trading off Clean Process Technology Options 28.7 Life Cycle Analysis 28.8 Clean Process Technology... expanded by 10% and a market source identified for the balance? Should the plant be expanded to 20% similarly? If a real expansion in the market place is anticipated and expansion to 30% would be very expensive, why not be more aggressive and instead of expanding the existing process, build an entirely new process? If a new process is to be built, then what should be the process technology? New process. .. integrates equipment, process and utility system design Chemical processing should form part of a sustainable industrial activity For chemical processing, this means that processes should use raw materials as efficiently as is economic and practicable, both to prevent the production of waste that can be environmentally harmful and to preserve the reserves of raw materials as much as possible Processes should . TheNatureofChemicalProcess 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. 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. 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 11 1.8 Process Control 13 1.9 The Nature of Chemical