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Heterogeneous Reactions.
1808
Book Reviews
Hydroeyclonea. By L. SVAROVSKY. Holt. Rinehart % Winston Ltd. 198 pp., El3.50 As the author correctly points out in the preface, this is the first new book solely devoted to hydrocyclones to appear for 20 years and on this account alone it merits attention. Stylistically the book has perhaps not entirely escaped its origin as course notes, the main defect being the brevity of treatment accorded the necessarily wide range of topics included. The layout of the book is well conceived and pursues a logical sequence from fundamental considerations through design and scale-up to applications. The introductory chapter on particlefluid interaction is written clearly and concisely. but confines itself to fine particles experiencing laminar motion. Many applications involve particles large enough to exhibit transitional regime motion and readers interested in this area must look elsewhere for relevant information. The review of separation efficiency in Chapter 2 recommends graphical techniques for obtaining grade efficiencies, whereas industrial practice is to employ the mass recovery (a term preferable to the “total efficiency” adopted by the author) in conjunction with the product size analyses to calculate the grade efficiencies and to smooth the data when plotting the calculated results. Surprisingly, the section devoted to sharpness of classification (2.1.11) omits any reference to the classification efficiency recommended by Taggert [Handbook of Mineral Dressing, pp. 199-200. Wiley (1945)] which still provides an excellent basis for assessing screening or classification efficiency. Chapter 3 gives a condensed but useful overview of fluid flow and particle motion within cyclones, including a discussion of the residence time distribution and spatial distribution of particles. The coverage of theoretical aspects is continued in the following chapter which reviews separation behaviour and divides the main types of physically based models into four categories: the equilibrium orbit, residence time. crowding and turbulent two-phase flow theories. The adoption of
Heterogeneous Reactions. By L. K. DURAISWAMY and M. M. SHARMA. John Wiley and Sons, New York, 1984, 2 Vols, Vol. 1 k80.95, Vol. 2 A72.50 These two volumes are basically encyclopaedic: very many different physical and chemical situations are discussed, often quite briefly. However, the appropriate fundamental physical chemistry, particularly of reactions occurring very near the various interfaces, is clearly set out. The worked examples of the various physicochemical theories in both volumes are very valuable: they could be of considerable help in teaching or learning reactor design. The present volumes can (unlike “Perry”, which they resemble in some ways) be read with little prior knowledge of the subject. Volume 1 is concerned with gas-solid and solidsolid reactions, and one section is devoted to immobilized enzyme and other catalyst systems, and one chapter to solid-lid reactions. Fluid&d beds are discussed, and the various correlations for bubble diameters are listed. Volume 2 covers the physical chemistry of mass transfer accompanied by reversible and irreversible reactions, mass transfer accompanied by consecutive and two-step reactions, gas absorption into a solution containing two reactants, and the simultaneous absorption and reaction of two gases. Also discussed is reaction occurring in both liquid phases, desorption with reaction, complex reactions, solid-liquid reactions,
dimensionless Stokes and Euler numbers to characterise the performance and to compare models is both logical and convenient. While some readers may not share the author’s preference for the crowding theory as the best hope for a comprehensive model, this portion of the book represents a valuable summary and critique of the main lines of theoretical development. Subsequent chapters devoted to the types of hydrocyclones currently available and to the installation and operational aspects provide information on current trends in cyclone design and some of the empirical models of cyclone behaviour are reviewed in conjunction with the operating characteristics. A short description of the effect of design variables is included in Chapter 7 and some recommended procedures for hydrocyclone selection and scale-up are provided in Chapter 8. The final two chapters discuss the case of hydrocyclones in various flow combinations and summarise the main areas of application with some consideration of associated aspects such as economics and safety. The text is well presented and the quality of the illustrations is high, with the emphasis on clear and uncluttered diagrams a welcome change from many current technical publications. There are several printer’s errors and some minor mistakes in reporting from quoted sources, but no more than would be expected in a first edition. The present book succeeds admirably in fulfilling the chosen aim of supplementing the previous texts and providing a self-contained teaching textbook. It does not attempt to fill the existing need for an authoritative treatise on this subject, though it is to he hoped that the author can be persuaded to expand the coverage and degree of detail in a future edition to fill this gap in the literature. The present volume nevertheless constitutes mandatory reading for all workers involved with hydrocyclones. A. B. HOLLAND-BAT-f Mineral BunduIl,
Deposits Ltd. Queensland, Australia
fluid-fluid-solid reactions and fluid-fluid systems with solid particles of a catalyst. The volume includes a chapter on the different types of contactors and their relative merits. Particularly interesting is Chapter 3, which is a discussion (with examples) of systems falling in the different regimes, including the important field of extraction accompanied by a chemical reaction. This is dealt with by specific examples, with a few paragraphs devoted to each, and with some references to the relevant literature. Sharma’s own work is extensively quoted throughout this volume. In both volumes, c.g.s. units are used rather than S.I. One can understand the authors’ problem here: with so much material reviewed, and with many of the published correlations and graphs in c.g.s., it would have been a major task to rework them all. Nevertheless, it would have been useful to write some of the correlations in both sets of units, and to present all the worked examples in S.I. Unfortunately, the indices are not very full: if, for example, one is interested in the water-gas shift reaction (found in Vol. 1, p. 147). it cannot be located in the index. The same applies, inter alia, to the vinyl acetate reactor (Vol. 1, p. 340) and the steam-reforming process (Vol. 1, p. 297). Similarly in volume 2: for example, cresol separations (Vol. 2, p. 181) are not listed in the index. The two volumes will form a most useful addition to a library. They are very readable, and lead one into fields where
Book the details and complexities might otherwise have proved too formidable. They contain a good blend of theory and practice at a relatively uncomplicated level, and they illustrate the need for specialist volumes with more detail and much more chemistry than is to be found in “Perry”, for example. The present volumes provide, moreover, a good introduction to the physical chemistry of reactor design. These volumes (they could be used separately) cover so much material (and are so costly) that they cannot be regarded as student textbooks. Rather, they are reference
Reviews
1809
books, though sometimes lacking the many detailed literature references (to reactions) that would be required by a research worker. They will, however, be of considerable help to those teaching the subjects, and to those in industry wishing to understand more of the fundamentals of the subject. At L80.95 and g2.50, these books are expensive. University of Birmingham Birmingham,
U.K.
J. T. DAVIES
Book Reviews
Hydroeyclonea. By L. SVAROVSKY. Holt. Rinehart % Winston Ltd. 198 pp., El3.50 As the author correctly points out in the preface, this is the first new book solely devoted to hydrocyclones to appear for 20 years and on this account alone it merits attention. Stylistically the book has perhaps not entirely escaped its origin as course notes, the main defect being the brevity of treatment accorded the necessarily wide range of topics included. The layout of the book is well conceived and pursues a logical sequence from fundamental considerations through design and scale-up to applications. The introductory chapter on particlefluid interaction is written clearly and concisely. but confines itself to fine particles experiencing laminar motion. Many applications involve particles large enough to exhibit transitional regime motion and readers interested in this area must look elsewhere for relevant information. The review of separation efficiency in Chapter 2 recommends graphical techniques for obtaining grade efficiencies, whereas industrial practice is to employ the mass recovery (a term preferable to the “total efficiency” adopted by the author) in conjunction with the product size analyses to calculate the grade efficiencies and to smooth the data when plotting the calculated results. Surprisingly, the section devoted to sharpness of classification (2.1.11) omits any reference to the classification efficiency recommended by Taggert [Handbook of Mineral Dressing, pp. 199-200. Wiley (1945)] which still provides an excellent basis for assessing screening or classification efficiency. Chapter 3 gives a condensed but useful overview of fluid flow and particle motion within cyclones, including a discussion of the residence time distribution and spatial distribution of particles. The coverage of theoretical aspects is continued in the following chapter which reviews separation behaviour and divides the main types of physically based models into four categories: the equilibrium orbit, residence time. crowding and turbulent two-phase flow theories. The adoption of
Heterogeneous Reactions. By L. K. DURAISWAMY and M. M. SHARMA. John Wiley and Sons, New York, 1984, 2 Vols, Vol. 1 k80.95, Vol. 2 A72.50 These two volumes are basically encyclopaedic: very many different physical and chemical situations are discussed, often quite briefly. However, the appropriate fundamental physical chemistry, particularly of reactions occurring very near the various interfaces, is clearly set out. The worked examples of the various physicochemical theories in both volumes are very valuable: they could be of considerable help in teaching or learning reactor design. The present volumes can (unlike “Perry”, which they resemble in some ways) be read with little prior knowledge of the subject. Volume 1 is concerned with gas-solid and solidsolid reactions, and one section is devoted to immobilized enzyme and other catalyst systems, and one chapter to solid-lid reactions. Fluid&d beds are discussed, and the various correlations for bubble diameters are listed. Volume 2 covers the physical chemistry of mass transfer accompanied by reversible and irreversible reactions, mass transfer accompanied by consecutive and two-step reactions, gas absorption into a solution containing two reactants, and the simultaneous absorption and reaction of two gases. Also discussed is reaction occurring in both liquid phases, desorption with reaction, complex reactions, solid-liquid reactions,
dimensionless Stokes and Euler numbers to characterise the performance and to compare models is both logical and convenient. While some readers may not share the author’s preference for the crowding theory as the best hope for a comprehensive model, this portion of the book represents a valuable summary and critique of the main lines of theoretical development. Subsequent chapters devoted to the types of hydrocyclones currently available and to the installation and operational aspects provide information on current trends in cyclone design and some of the empirical models of cyclone behaviour are reviewed in conjunction with the operating characteristics. A short description of the effect of design variables is included in Chapter 7 and some recommended procedures for hydrocyclone selection and scale-up are provided in Chapter 8. The final two chapters discuss the case of hydrocyclones in various flow combinations and summarise the main areas of application with some consideration of associated aspects such as economics and safety. The text is well presented and the quality of the illustrations is high, with the emphasis on clear and uncluttered diagrams a welcome change from many current technical publications. There are several printer’s errors and some minor mistakes in reporting from quoted sources, but no more than would be expected in a first edition. The present book succeeds admirably in fulfilling the chosen aim of supplementing the previous texts and providing a self-contained teaching textbook. It does not attempt to fill the existing need for an authoritative treatise on this subject, though it is to he hoped that the author can be persuaded to expand the coverage and degree of detail in a future edition to fill this gap in the literature. The present volume nevertheless constitutes mandatory reading for all workers involved with hydrocyclones. A. B. HOLLAND-BAT-f Mineral BunduIl,
Deposits Ltd. Queensland, Australia
fluid-fluid-solid reactions and fluid-fluid systems with solid particles of a catalyst. The volume includes a chapter on the different types of contactors and their relative merits. Particularly interesting is Chapter 3, which is a discussion (with examples) of systems falling in the different regimes, including the important field of extraction accompanied by a chemical reaction. This is dealt with by specific examples, with a few paragraphs devoted to each, and with some references to the relevant literature. Sharma’s own work is extensively quoted throughout this volume. In both volumes, c.g.s. units are used rather than S.I. One can understand the authors’ problem here: with so much material reviewed, and with many of the published correlations and graphs in c.g.s., it would have been a major task to rework them all. Nevertheless, it would have been useful to write some of the correlations in both sets of units, and to present all the worked examples in S.I. Unfortunately, the indices are not very full: if, for example, one is interested in the water-gas shift reaction (found in Vol. 1, p. 147). it cannot be located in the index. The same applies, inter alia, to the vinyl acetate reactor (Vol. 1, p. 340) and the steam-reforming process (Vol. 1, p. 297). Similarly in volume 2: for example, cresol separations (Vol. 2, p. 181) are not listed in the index. The two volumes will form a most useful addition to a library. They are very readable, and lead one into fields where
Book the details and complexities might otherwise have proved too formidable. They contain a good blend of theory and practice at a relatively uncomplicated level, and they illustrate the need for specialist volumes with more detail and much more chemistry than is to be found in “Perry”, for example. The present volumes provide, moreover, a good introduction to the physical chemistry of reactor design. These volumes (they could be used separately) cover so much material (and are so costly) that they cannot be regarded as student textbooks. Rather, they are reference
Reviews
1809
books, though sometimes lacking the many detailed literature references (to reactions) that would be required by a research worker. They will, however, be of considerable help to those teaching the subjects, and to those in industry wishing to understand more of the fundamentals of the subject. At L80.95 and g2.50, these books are expensive. University of Birmingham Birmingham,
U.K.
J. T. DAVIES