Principles and Applications of Mass Transfer E-Book

Jaime Benitez

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 878

Veröffentlichungsjahr: 2022

Beschreibung

Principles and Applications of Mass Transfer

Core textbook teaching mass transfer fundamentals and applications for the design of separation processes in chemical, biochemical, and environmental engineering

Principles and Applications of Mass Transfer teaches the subject of mass transfer fundamentals and their applications to the design of separation processes with enough depth of coverage to guarantee that students using the book will, at the end of the course, be able to specify preliminary designs of the most common separation process equipment.

Reflecting the growth of biochemical applications in the field of chemical engineering, the fourth edition expands biochemical coverage, including transient diffusion, environmental applications, electrophoresis, and bioseparations. Also new to the fourth edition is the integration of Python programs, which complement the Mathcad programs of the previous edition.

On the accompanying instructor’s website, the online appendices contain a downloadable library of Python and Mathcad programs for the example problems in each chapter. A complete solution manual for all end-of-chapter problems, both in Mathcad and Python, is also provided.

Some of the topics covered in Principles and Applications of Mass Transfer include:

• Molecular mass transfer, covering concentrations, velocities and fluxes, the Maxwell-Stefan relations, and Fick’s first law for binary mixtures
• The diffusion coefficient, covering diffusion coefficients for binary ideal gas systems, dilute liquids, and concentrated liquids
• Convective mass transfer, covering mass-transfer coefficients, dimensional analysis, boundary layer theory, and mass- and heat-transfer analogies
• Interphase mass transfer, covering diffusion between phases, material balances, and equilibrium-stage operations
• Gas dispersed gas-liquid operations, covering sparged vessels, tray towers, diameter, and gas-pressure drop, and weeping and entrainment

Principles and Applications of Mass Transfer is an essential textbook for undergraduate chemical, biochemical, mechanical, and environmental engineering students taking a core course on Separation Processes or Mass Transfer Operations, along with mechanical engineers and mechanical engineering students starting to get involved in combined heat- and mass-transfer applications.

Leseprobe

PRINCIPLES AND APPLICATIONS OF MASS TRANSFER

The Design of Separation Processes for Chemical and Biochemical Engineering

Fourth Edition

Jaime Benitez

This edition first published 2023

© 2023 John Wiley & Sons, Inc.

Edition History

3e © 2017 by John Wiley & Sons, Inc.

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The right of Jaime Benitez to be identified as the author of this work has been asserted in accordance with law.

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In view of ongoing research, equipment modifications, changes in governmental regulations, and the constant flow of information relating to the use of experimental reagents, equipment, and devices, the reader is urged to review and evaluate the information provided in the package insert or instructions for each chemical, piece of equipment, reagent, or device for, among other things, any changes in the instructions or indication of usage and for added warnings and precautions. While the publisher and authors have used their best efforts in preparing this work, they make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives, written sales materials or promotional statements for this work. The fact that an organization, website, or product is referred to in this work as a citation and/or potential source of further information does not mean that the publisher and authors endorse the information or services the organization, website, or product may provide or recommendations it may make. This work is sold with the understanding that the publisher is not engaged in rendering professional services. The advice and strategies contained herein may not be suitable for your situation. You should consult with a specialist where appropriate. Further, readers should be aware that websites listed in this work may have changed or disappeared between when this work was written and when it is read. Neither the publisher nor authors shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages.

Library of Congress Cataloging-in-Publication Data

Names: Benitez, Jaime, 1948- author.Title: Principles and applications of mass transfer : the design of separation processes for chemical and biochemical engineering / Jaime Benitez.Other titles: Principles and modern applications of mass transfer operations Description: Fourth edition. | Hoboken, NJ : John Wiley & Sons Inc., 2023.| Revised edition of: Principles and modern applications of mass transfer operations / Jamie Benitez. Third edition. 2017. | Includes bibliographical references and index. Identifiers: LCCN 2022034854 (print) | LCCN 2022034855 (ebook) | ISBN 9781119785248 (hardback) | ISBN 9781119785255 (pdf) | ISBN 9781119785262 (epub) Subjects: LCSH: Mass transfer. | Chemical engineering. Classification: LCC TP156.M3 B44 2023 (print) | LCC TP156.M3 (ebook) | DDC 660/.28423--dc23/eng/20220726 LC record available at https://lccn.loc.gov/2022034854LC ebook record available at https://lccn.loc.gov/2022034855

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A nuestro hijo, Jaime, un verdadero milagro de supervivencia. A nuestros nietosTeresita, Oliver y Diego; que la vida les sonría.

Preface to the Fourth Edition

The new title of this edition has the objective of increasing the discoverability of the book by college instructors. When the book was first published two decades ago, most chemical engineering departments had a required course titled Mass-Transfer Operations. However, now the name of the course has changed in most US universities to Separation Processes; and the name of most of the departments have changed to Chemical and Biochemical Engineering. The content of the book is basically unchanged (highlighting the biochemical applications already in the previous edition and some added biochemical content), just the name has changed. The material covered in this book is still perfectly appropriate for the course. I suggested eliminating from the title of the book the word “modern” because it is really aimed to be used in a first course of separation processes and the emphasis is on classical processes such as distillation and gas absorption.

This edition incorporates, for the first time, the use of Python, a very useful computational tool. Python is a free, open-source language and environment that has tremendous potential for use within the domain of scientific and technical computing. It is a modern language (object oriented) that is concise, easy to read, and quick to learn. It is full of freely available libraries, in particular scientific ones such as linear algebra, visualization tools, plotting, differential equations solving, statistics, and many more. It is widely used in industrial applications. Learning to use Python for engineering calculations is a very desirable and valuable skill for chemical engineers.

A distinguishing feature of the first three editions of this book was the incorporation of Mathcad for both example problems and homework questions. The fourth edition maintains the use of Mathcad but supplemented with the corresponding Python versions of the programs. Appendices were added to each chapter to include in them the corresponding Python versions of the example problems of the given chapter solved by Mathcad. The library of Mathcad programs in the appendices at the end of the book were also supplemented with the corresponding Python versions. This constitutes the most significant modification of the book content. Other differences in this edition are listed in the following paragraph.

Chapter 1 includes a new section on transient molecular diffusion in solids. Chapter 3 includes an analysis of equilibrium thermodynamics of biochemical systems. A new section on extraction of bioproducts was added to Chapter 7. Electrophoresis and the use of membranes for bioseparations were included in Chapter 9. Additional end-of-chapter problems related to environmental and biochemical applications were added throughout the book.

I want to acknowledge all the help provided to me by Katrina Maceda, Kanimozhi Ramamurthy, and Summers Scholl from Wiley. It was a pleasure working with you. I want to also acknowledge the help from Prof. Bruce A. Finlayson. He is Professor Emeritus of Chemical Engineering at the University of Washington and has published extensively in computational methods for chemical engineering, including Python. I have followed and admired his distinguished career ever since I was a graduate student. I wish him health and a long life to enjoy his retirement and many hobbies. Thanks again to my wife Teresa for her unconditional love and support, especially during the dark times of the COVID-19 pandemic.

Jaime Benítez

Gainesville, Florida

Preface to the Third Edition

The most significant difference between the first two editions and the third edition is the adoption in the latter of PTC Mathcad Prime most recent version (version 3.1 as of this writing). PTC Mathcad Prime—one of the world’s leading tools for technical computing in the context of engineering, science, and math applications—is a significant departure from the previous versions of Mathcad. There is a definite learning curve associated with making the switch from Mathcad to Mathcad Prime. However, the new features included in Mathcad Prime make switching from Mathcad worthwhile. Besides, programs written for the previous versions of Mathcad will not run in Mathcad Prime. Other differences in this edition are listed in the following paragraphs.

In Chapter 3 of the third edition, the material covered in Problems 3.14 and 3.15 of the second edition to determine analytically minimum flow rates in absorbers and strippers is incorporated in the theoretical presentation of Section 3.4 (Material Balances), and the corresponding Mathcad Prime code for solving these problems is given. In Section 3.5 of the third edition, Mathcad Prime code is given to determine analytically the number of ideal stages required for absorbers and strippers.

Section 4.2 of the third edition use, exclusively, the updated Billet and Schultes correlations for estimating the loading and flooding points in packed beds, and the corresponding gas-pressure drop for operation between these limits. The Generalized Pressure Drop Correlation (GPDC) is not included. The updated Billet and Schultes correlations are also used to estimate the volumetric mass-transfer coefficients in both liquid and gas phases. New end-of-chapter problems have been added throughout this third edition.

I want to acknowledge the extraordinarily thorough editing job that Katrina Maceda, Production Editor at Wiley, and Baljinder Kaur, Project Manager at Aptara did on this edition. The book is much better now because of them. It was a pleasure working with both of you. Ludo de Wolf, a physical therapist with gifted hands and a delightful sense of humor, literally removed from my shoulders the heavy load of completing this edition. Thanks to my wife Teresa for her unconditional love and support. I know it is not easy!

Jaime Benítez

Gainesville, Florida

Preface to the Second Edition

The idea for the first edition of this book was born out of my experience teaching a course on mass-transfer operations at the Chemical Engineering Department of the University of Puerto Rico during the previous 25 years. This course is the third in a three-course unit operations sequence. The first course covers momentum transfer (fluid mechanics), and the second course covers heat transfer. Besides these two courses, another prerequisite of the mass-transfer course is a two-semester sequence of chemical engineering thermodynamics.

I decided to write a textbook for a first course on mass-transfer operations with a level of presentation that was easy to follow by the reader, but with enough depth of coverage to guarantee that students using the book will, upon successful completion of the course, be able to specify preliminary designs of the most common mass-transfer equipment (such as absorbers, strippers, distillation columns, liquid extractors, etc.). I decided also to incorporate, from the very beginning of the book, the use of Mathcad, a computational tool that is, in my opinion, very helpful and friendly. The first edition of this book was the result of that effort.

Part of my objective was achieved, as evidenced by the following excerpt from a very thorough review of the first edition of my book, written by Professor Mark J. McCready, a well-known expert in chemical engineering education: “If the topics that are needed for a given course are included in this text, I would expect the educational experience to go smoothly for both student and instructor. I think that students will like this book, because the explanations are clear, the level of difficulty is appropriate, and the examples and included data give the book very much of a ‘handbook’ flavor. Instructors will find that, overall, the topics are presented in a logical order and the discussion makes sense; there are many examples and lots of homework problems” (McCready, M. J., AIChE J., Vol. 49, No. 1, January 2003).

“Each major section of the book has learning objectives which certainly benefit the students and perhaps the instructor. A key feature of the book, which separates it from the other texts mentioned above, is the incorporation of Mathcad for both example problems and homework questions. A library of Mathcad programs for solving the Maxwell-Stefan equations, packed column calculations, sieve-tray design, binary distillation problems by McCabe-Thiele method, and multistage crosscurrent extraction is given in the appendices. These programs enable students to obtain useful solutions with less effort, as well as allow them to explore the different variables or parameters. The wide availability, low cost, and ease of use of Mathcad allow it to be the modern equivalent of “back of the envelope’ calculations, which can be refined, if necessary, using full-scale process simulators” (McCready, 2003).

However, the same reviewer also points out some limitations of the book. One of the main objectives of this second edition is to remedy those shortcomings of the first edition to make it more attractive as a textbook to a broader audience. Another important objective of the second edition is to incorporate material related to mass-transfer phenomena in biological systems. Many chemical engineering departments all over the world are changing their names and curricula to include the area of biochemical engineering in their offerings. The second edition includes pertinent examples such as convection and diffusion of oxygen through the body’s circulatory system, bio-artificial kidneys, separation of sugars by chromatography, and purification of monoclonal antibodies by affinity adsorption.

As with the first edition, the first four chapters of the book present a basic framework for analysis that is applicable to most mass-transfer operations. Chapters 5 to 7 apply this common methodology to the analysis and design of some of the most popular types of mass-transfer operations. Chapter 5 covers gas absorption and stripping; Chapter 6 covers distillation; and Chapter 7 covers liquid extraction. Chapter 8, new to the second edition, covers humidification operations in general, and detailed design of packed cooling towers specifically. These operations—in particular, cooling towers—are very common in industry. Also, from the didactic point of view, their analysis and design involve simultaneous mass- and heat-transfer considerations. Therefore, the reader is exposed in detail to the similarities and differences between these two transport phenomena. Chapter 9, also new, covers mass-transfer processes using barriers (membranes) and solid sorption agents (adsorption, ion exchange, and chromatography).

In response to suggestions by Professor McCready and other reviewers, some other revisions and additions to the second edition are:

In

Chapter 1

, the Maxwell-Stefan equations (augmented by the steady-state continuity equation for each component) are solved numerically using a combination of a Runge-Kutta-based differential equation solver (

Rkfixed

) and an algebraic equation solver (

Given-Find

), both included in Mathcad. This methodology is much more flexible than the one presented in the first edition (orthogonal collocation), and its theoretical justification is well within the scope of the mathematical background required for a first course in mass-transfer operations.

Chapter 1 includes a section on diffusion in solids.

Chapter 2 includes a section on boundary-layer theory and an example on simultaneous mass and heat transfer during air humidification.

Chapter 6 includes a section on multistage batch distillation.

I wish to acknowledge gratefully the contribution of the University of Puerto Rico at Mayagüez to this project. My students in the course INQU 4002 reviewed the material in the book, found quite a few errors, and gave excellent suggestions on ways to improve its content and presentation. My students are my source of motivation; they make all the effort to prepare this book worthwhile!

Jaime Benítez

Mayagüez, Puerto Rico

Preface to the First Edition

The importance of the mass-transfer operations in chemical processes is profound. There is scarcely any industrial process that does not require a preliminary purification of raw materials or final separation of products. This is the realm of mass-transfer operations. Frequently, the major part of the cost of a process is that for the separations accomplished in the mass-transfer operations, a good reason for process engineers and designers to master this subject. The mass-transfer operations are largely the responsibility of chemical engineers, but increasingly practitioners of other engineering disciplines are finding them necessary for their work. This is especially true for those engaged in environmental engineering, where separation processes predominate.

My objective in writing this book is to provide a means to teach undergraduate chemical engineering students the basic principles of mass transfer and to apply these principles, aided by modern computational tools, to the design of equipment used in separation processes. The idea for it was born out of my experiences during the last 25 years teaching mass-transfer operations courses at the University of Puerto Rico.

The material treated in the book can be covered in a one-semester course. Chapters are divided into sections with clearly stated objectives at the beginning. Numerous detailed examples follow each brief section of text. Abundant end-of-chapter problems are included, and problem degree of difficulty is clearly labeled for each. Most of the problems are accompanied by their answers. Computer solution is emphasized, both in the examples and in the end- of-chapter problems. The book uses mostly SI units, which virtually eliminates the tedious task of unit conversions and makes it “readable” to the international scientific and technical community.

Following the lead of other authors in the chemical engineering field and related technical disciplines, I decided to incorporate the use of Mathcad into this book. Most readers will probably have a working knowledge of Mathcad. (Even if they don’t, my experience is that the basic knowledge needed to begin using Mathcad effectively can be easily taught in a two-hour workshop.) The use of Mathcad simplifies mass-transfer calculations to a point that it allows the instructor and the student to readily try many different combinations of the design variables, a vital experience for the amateur designer.

The Mathcad environment can be used as a sophisticated scientific calculator, can be easily programed to perform a complicated sequence of calculations (for example, to check the design of a sieve-plate column for flooding, pressure drop, entrainment, weeping, and calculating Murphree plate efficiencies), can be used to plot results, and as a word processor to neatly present homework problems. Mathcad can perform calculations using a variety of unit systems, and will give a warning signal when calculations that are not dimensionally consistent are tried. This is a most powerful didactic tool, since dimensional consistency in calculations is one of the most fundamental concepts in chemical engineering education.

The first four chapters of the book present a basic framework of analysis that is applicable to any mass-transfer operation. Chapters 5 to 7 apply this common methodology to the analysis and design of the most popular types of mass-transfer operations. Chapter 5 covers gas absorption and stripping, chapter 6 distillation columns, and chapter 7 liquid extraction. This choice is somewhat arbitrary, and based on my own perception of the relevance of these operations. However, application of the general framework of analysis developed in the first four chapters should allow the reader to master, with relative ease, the peculiarities of any other type of mass-transfer operation.

I wish to acknowledge gratefully the contribution of the University of Puerto Rico at Mayagüez to this project. My students in the course INQU 4002 reviewed the material presented in the book, found quite a few errors, and gave excellent suggestions on ways to improve it. My special gratitude goes to Teresa, my wife, and my four children who were always around lifting my spirits during the long, arduous hours of work devoted to this volume. They make it all worth-while!

Jaime Benítez

Mayagüez, Puerto Rico

1 Fundamentals of Mass Transfer

1.1 INTRODUCTION

When a system contains two or more components whose concentrations vary from point to point, there is a natural tendency for mass to be transferred, minimizing the concentration differences within the system, and moving it toward equilibrium. The transport of one component from a region of higher concentration to that of a lower concentration is called mass transfer.