Particle Technology Series – serie

Chemistry of Powder Production focuses on the solid-state chemistry of powder materials and relates this to the structure, properties and preparation, and characterization techniques for these important industrial products. Additionally, the properties of the particles are discussed in relation to their surface structure and characteristics. This book describes the fundamentals of statistical methods for measuring the characteristics of particles. New advanced materials being developed in powder technology manufacturing techniques are also emphasised, including powdered materials for advanced ceramics as well as magnetic and pigment materials.

The rapid growth of interest in powders and their surface properties in many diverse industries prompted the writing of this book for those who have the need to make meaningful measurements without the benefit of years of experience. It is intended as an introduction to some of the elementary theory and experimental methods used to study the surface area, porosity, density, and particle size of powders. It may be found useful by those with little or no training in solid surfaces who have the need to learn quickly the rudiments of surface area, density, pore size, and particle size measurements. S. Lowell J.E. Shields Symbols Use of symbols for purposes other than those indicated in the following table are so defined in the text. Some symbols not shown in the table are also defined in the text. d adsorbate cross-sectional area A area; condensation coefficient; collision frequency C BET constant c concentration D diameter; coefficient of thermal diffusion E adsorption potential permeability aspect factor f F flow rate; force; feed rate g gravitational constant G Gibbs free energy S G free surface energy h heat of immersion per unit area; height H enthalpy heat of immersion Hi heat of adsorption Hsv BET intercept; filament current k thermal conductivity; specific reaction rate K Harkins-Jura constant C length L heat of liquefaction M mass M molecular weight MPa megapascals number of moles n number of molecules; number of particles N N Avogadro's num'ber molecular collisions per square cm per second

The operation of a powder mixer requires a knowledge not only of the mixing mechanisms but of the physical properties of the powders being mixed. Powder Mixing is unique in that it explores the relevant physics of the powder systems including characterization procedures and rheology, and contains an extensive review of different methods that have been employed to study the structure of mixtures.The techniques for achieving structured mixtures such as microencapsulation, and recent developments in deterministic chaos theory and fractal geometry as applied to the study of powder mixing systems, are reviewed. In particular, new techniques for studying the mixing powders based on avalanching theory and critically self-organized systems are studied. These are followed by a review of the wide range of different mixers commercially available and an extensive bibliography.Powder Mixing is an essential reference for all those interested in the basic science of powder mixing and the availability of industrial systems to achieve a mixture of different kinds. The main emphasis of the text is on working principles and operative systems, and is suitable for industrial workers, chemical engineers and students alike.

This work describes the different operational regimes and the dominant mechanisms of flows in disperse systems.

The fundamentals of wet classification are described and a scientific basis for solving classification is presented. For the practical engineer, there is an overview of the technical solutions available.

This text should be of interest to all those concerned with the preparation, processing and analysis of disperse systems. There are a wide range of methods and devices available to provide information on the quantative distribution of the characteristics of particle size and shape to select from and the choice is by no means an easy one. By restricting coverage to classification and sedimentation methods this book intends to assist with the choice of technique as well as promote a deeper understanding of the theoretical foundations, which are scattered over many branches of science. The technical problems of measurement are illustrated as are their effect on the interpretation of results. A certain degree of experience in the field is presupposed and as such, this book should prove to be an invaluable reference text for powder technologist in a wide range of industries as well as graduates and researchers in chemical engineering, materials science and environmental engineering.

A prestigious form of research grant in Germany is the Sonderforschungsbereich, which provides continuous funding over a period of up to 15 years, but only as long as the work is yielding worthwhile results. We acknowledge financial support of our work at Erlangen by the Deutsche Forschungsgemeinschaft (DFG), Sonder- forschungsbereich 222. Thanks to this support, the experimental results from six Dr. -Ing. dissertations have provided the basis for our book: 8 * Schweinzer, J. (1987) Heat transfer in bubbling fluidized beds at Ar;a. 10 * Seiter, M. (1990) Particle motion and solids concentration in circulating fluidized beds * Mattmann, W. (1991) Heat transfer in pressurized circulating fluidized beds * Burschka, A. (1993) Pulsed light method * Dietz, S. (1994) Heat transfer in bubbling fluidized beds * Gruber, U. (1995) Heat transfer in lean phase systems This book is the result of the enthusiastic and trustful cooperation of its authors. Nevertheless, we are separate individuals. Chapters 1 to 12 and 19 are by O. Molerus; Chapters 13 to 18 are by K. -E. Wirth.This book came into existence after many rewrites, patiently endured by Mrs Winter, who typed all versions of the manuscript, and by Mrs Scheffler-Kohler, who drew all the figures. Bob Farmer and David Penfold helped us bridge the language gap to produce a readable book. Weare grateful to Professor Brian Scarlett of Delft University, who on behalf of Chapman & Hall allowed us to write this book.

This is the fifth edition of the highly successful work first published in 1968, comprising two definitive volumes on particle characterisation. The first volume is devoted to sampling and particle size measurement, while surface area and pore size determination are reviewed in volume 2.Particle size and characterisation are central to understanding powder properties and behaviour. This book describes numerous potential measuring devices, how they operate and their advantages and disadvantages. It comprise a fully comprehensive treatise on the wide range of available equipment with an extensive literature survey, and a list of manufacturers and suppliers.The author's blend of academic and industrial experience results in a readable technical book with information on how to analyse, present, and extract useful information from data. This is an essential reference book for both industrial and academic research workers in a variety of areas including: pharmaceuticals, food science, pollution analysis and control, electronic materials, agricultural products, polymers, pigments and chemicals.

This is the fifth edition of the highly successful work first published in 1968, comprising two definitive volumes on particle characterisation. The first volume is devoted to sampling and particle size measurement, while surface area and pore size determination are reviewed in volume 2.Particle size and characterisation are central to understanding powder properties and behaviour. This book describes numerous potential measuring devices, how they operate and their advantages and disadvantages. It comprise a fully comprehensive treatise on the wide range of available equipment with an extensive literature survey, and a list of manufacturers and suppliers.The author's blend of academic and industrial experience results in a readable technical book with information on how to analyse, present, and extract useful information from data. This is an essential reference book for both industrial and academic research workers in a variety of areas including: pharmaceuticals, food science, pollution analysis and control, electronic materials, agricultural products, polymers, pigments and chemicals.

A two-volume set on particle characterization. Volume one deals with sampling and particle size management, while surface area and pore size determination are reviewed in volume two. Particle size and characterization are central to understanding powder properties and behaviour. The volumes describe potential measuring devices, how they operate, and their advantages and disadvantages. It comprises a comprehensive treatise on the range of available equipment with a literature survey, and a list of manufacturers and suppliers. The books show how to analyze, present and extract useful information from the data.

Over half of the products of the chemical and process industries are sold in a particulate form. The range of such products is vast: from agrochemicals to pigments, from detergents to foods, from plastics to pharmaceuticals. However, surveys of the performance of processes designed to produce particulate products have consistently shown inadequate design and poor reliability. `Particle technology' is a new subject facing new challenges. Chemical and process engineering is becoming less concerned with the design of plants to produce generic simple chemicals (which are often single phase fluids) and is now more concerned with speciality `effect' chemicals which may often be in particulate form. Chemical and process engineers are also being recruited in increasing numbers into areas outside their tranditional fields, such as the food industry, pharmaceuticals and the manufacture of a wide variety of consumer products. This book has been written to meet their needs. It provides comprehensive coverage of the technology of particulate solids, in a form which is both accessible and concise enough to be useful to engineering and science students in the final year of an undergraduate degree, and at Master's level. Although it was written with students of chemical engineering in mind, it will also be of use and interest to students of other disciplines. It comprises an account of the fundamentals of teh subject, illustrated by worked examples, and followed by a wide range of selected applications.

This book is a welcome edition to the Particle Technology Series, formerly Powder Technology Series. It is the second book in the series which describes powder mixing and we make no excuses for that. The topic of powder mixing is fundamental to powder technology and is one which always aroses interest. That will not change. As powder products become more complex they will pose new mixing problems. The solutions lie in the intelligent use of equipment, an understanding of powder properties and a good knowledge of basic statistics. The authors of this book have presented those three ingredients with great clarity. The book is based on long experience and deep thought, I have enjoyed reading it and am pleased to recommend it. Delft University of Technology, NL-Delft, July 1999 Brian Scarlett, Series Editor IX VII Foreword to the English Edition In response to many enquiries from industrial organisations and institutes involved with the technology of processing bulk materials, we are pleased to present the English edition ,,Mixing of Solids". The text is based on the first edition written in the German language "Mischen von Schiittgiitern" [1]. The English version has been revised and updated to include the most recent re­ search developments, the conclusions of which have been taken into account.

Particle characterization is an important component in product research and development, manufacture, and quality control of particulate materials and an important tool in the frontier of sciences, such as in biotechnology and nanotechnology. This book systematically describes one major branch of modern particle characterization technology - the light scattering methods. This is the first monograph in particle science and technology covering the principles, instrumentation, data interpretation, applications, and latest experimental development in laser diffraction, optical particle counting, photon correlation spectroscopy, and electrophoretic light scattering. In addition, a summary of all major particle sizing and other characterization methods, basic statistics and sample preparation techniques used in particle characterization, as well as almost 500 latest references are provided. The book is a must for industrial users of light scattering techniques characterizing a variety of particulate systems and for undergraduate or graduate students who want to learn how to use light scattering to study particular materials, in chemical engineering, material sciences, physical chemistry and other related fields.

Particle characterization is an important component in product research and development, manufacture, and quality control of particulate materials and an important tool in the frontier of sciences, such as in biotechnology and nanotechnology. This book systematically describes one major branch of modern particle characterization technology - the light scattering methods. This is the first monograph in particle science and technology covering the principles, instrumentation, data interpretation, applications, and latest experimental development in laser diffraction, optical particle counting, photon correlation spectroscopy, and electrophoretic light scattering. In addition, a summary of all major particle sizing and other characterization methods, basic statistics and sample preparation techniques used in particle characterization, as well as almost 500 latest references are provided. The book is a must for industrial users of light scattering techniques characterizing a variety of particulate systems and for undergraduate or graduate students who want to learn how to use light scattering to study particular materials, in chemical engineering, material sciences, physical chemistry and other related fields.

The interest in control of particulate processes has been triggered by the need to achieve tight distributed control of size distributions that greatly influence particulate product properties and quality. Drawing from advances in dynamics of infinite-dimensional systems and nonlinear control theory, control of particulate processes using population balances has evolved into a very active research area within the field of process control. This book presents general methods for the synthesis of nonlinear, robust and constrained feedback controllers for broad classes of particulate process models and illustrates their applications to industrially-important crystallization, aerosol and thermal spray processes. The controllers use a finite number of measurement sensors and control actuators to achieve stabilization of the closed-loop system, output tracking, attenuation of the effect of model uncertainty and handling of actuator saturation.Beginning with an introduction to control of particulate processes, the book discusses nonlinear order reduction and nonlinear, robust and constrained control of particulate spatially-homogeneous processes, and nonlinear control of spatially-homogeneous particulate processes. The synthesis of the controllers is performed by using geometric and Lyapunov-based control techniques. The book includes comparisons of the methods followed for controller synthesis with other approaches and discussions of practical implementation issues that can help researchers and engineers understand the development and application of the methods in greater depth. The methods are applied to continuous and batch crystallization processes, a titania aerosol reactor and a thermal spray process to regulate product size distribution. The resulting benefits in closed-loop performance, robustness and actuator saturation handling compared to other techniques for control of particulate processes are demonstrated through computer simulations. The book assumes a basic knowledge about population balances and nonlinear control.

This book had its origins in a meeting between two (relatively) young particle technology researchers on Rehobeth Beach in Delaware in 1992 near the holiday house of Reg Davies (then Director of the Particle Science and Technology Research Center in Dupont). As we played in the sand, we shared an excitement for developments in particle technology, especially particle characterization, that would lead operations such as granulation to be placed on a sound scientific and engineering footing. The immediate outcome from this interaction was the development of new industry short courses in granulation and related topics which we taught together both in Australia and North America. This book follows closely the structure and approaches developed in these courses, particularly the emphasis on particle design in granulation, where the impact of both formulation properties and process variables on product attributes needs to be understood and quantified. The book has been a long time in the making. We have been actively preparing the book for at least five years. Although the chapters have relatively good bibliographies, this book is not a review of the field. Rather it is an attempt by the authors to present a comprehensive engineering approach to granulator design, scale up and operation. It is exciting for us to see the explosion of research interest around the world in this area in the last five to seven years. Some of the most recent work will have to find its way into the second edition.

The growth of interest in newly developed porous materials has prompted the writing of this book for those who have the need to make meaningful measurements without the benefit of years of experience. One might consider this new book as the 4th edition of "Powder Surface Area and Porosity" (Lowell & Shields), but for this new edition we set out to incorporate recent developments in the understanding of fluids in many types of porous materials, not just powders. Based on this, we felt that it would be prudent to change the title to "Characterization of Porous Solids and Powders: Surface Area, Porosity and Density". This book gives a unique overview of principles associated with the characterization of solids with regard to their surface area, pore size, pore volume and density. It covers methods based on gas adsorption (both physi­ and chemisorption), mercury porosimetry and pycnometry. Not only are the theoretical and experimental basics of these techniques presented in detail but also, in light of the tremendous progress made in recent years in materials science and nanotechnology, the most recent developments are described. In particular, the application of classical theories and methods for pore size analysis are contrasted with the most advanced microscopic theories based on statistical mechanics (e.g. Density Functional Theory and Molecular Simulation). The characterization of heterogeneous catalysts is more prominent than in earlier editions; the sections on mercury porosimetry and particularly chemisorption have been updated and greatly expanded.

This book focuses on the practical aspects of particle size measurement: a major difference with existing books, which have a more theoretical approach. Of course, the emphasis still lies on the measurement techniques. For optimum application, their theoretical background is accompanied by quantitative quality aspects, limitations and problem identification. In addition the book covers the phenomena of sampling and dispersion of powders, either of which may be dominant in the overall analysis error. Moreover, there are chapters on the general aspects of quality for particle size analysis, quality management, reference materials and written standards, in- and on-line measurement, definitions and multilingual terminology, and on the statistics required for adequate interpretation of results. Importantly, a relation is made to product performance, both during processing as well as in final application. In view of its set-up, this book is well suited to support particle size measurement courses.

This book puts forward the concept of the Diameter-Transformed Fluidized Bed (DTFB): a fluidized bed characterized by the coexistence of multiple flow regimes and reaction zones, achieved by transforming the bed into several sections of different diameters. It reviews fundamental aspects, including computational fluid dynamics simulations and industrial practices in connection with DTFB. In particular, it highlights an example concerning the development of maximizing iso-paraffins (MIP) reactors for regulating complex, fluid catalytic cracking reactions in petroleum refineries. The book is a must-have for understanding how academic and industrial researchers are now collaborating in order to develop novel catalytic processes.

This book puts forward the concept of the Diameter-Transformed Fluidized Bed (DTFB): a fluidized bed characterized by the coexistence of multiple flow regimes and reaction zones, achieved by transforming the bed into several sections of different diameters. It reviews fundamental aspects, including computational fluid dynamics simulations and industrial practices in connection with DTFB. In particular, it highlights an example concerning the development of maximizing iso-paraffins (MIP) reactors for regulating complex, fluid catalytic cracking reactions in petroleum refineries. The book is a must-have for understanding how academic and industrial researchers are now collaborating in order to develop novel catalytic processes.

This book describes different aspects of characterization and detection of nanomaterials in liquid disperse systems, such as suspensions, emulsions and suspoemulsions. Natural and technical particulate nanomaterials (NMs) are often present in formulations and products consisting of several disperse phases and complex dispersion media. Specific interfacial properties of the particles, their interactions with each other and with the dispersion medium, have to be considered. For example, the interfacial properties determine whether the particles tend to be arranged in aqueous or lipid phases or at their phase boundaries. The interfacial properties are significantly influenced by the adsorption of dissolved species, i.e., they depend on the composition of the dispersion medium. This poses great challenges for the characterization of these nanoparticle systems and requires adequate preparation methods. The nanoparticle measurement techniques aim at a deep physico-chemical understanding of the dispersity state of nanoparticle systems. Since the dispersity state of nanoparticle systems in an application usually does not correspond to their original manufacturing process, the formulation of new or improved product properties is of decisive importance. The characterization of nanoparticles in complex formulations or matrices requires an adequate sample preparation based on an existing or yet to be developed Standard Operating Procedure (SOP). The structure of the SOPs includes the dispersion regulations, which are of essential importance for comparing reproducible results of nanoparticle measurement with respect to comparability and transferability worldwide. The aim is to separate and isolate relevant NMs with knowledge of the interrelationships.

This book describes different aspects of characterization and detection of nanomaterials in liquid disperse systems, such as suspensions, emulsions and suspoemulsions. Natural and technical particulate nanomaterials (NMs) are often present in formulations and products consisting of several disperse phases and complex dispersion media. Specific interfacial properties of the particles, their interactions with each other and with the dispersion medium, have to be considered. For example, the interfacial properties determine whether the particles tend to be arranged in aqueous or lipid phases or at their phase boundaries. The interfacial properties are significantly influenced by the adsorption of dissolved species, i.e., they depend on the composition of the dispersion medium. This poses great challenges for the characterization of these nanoparticle systems and requires adequate preparation methods. The nanoparticle measurement techniques aim at a deep physico-chemical understanding of the dispersity state of nanoparticle systems. Since the dispersity state of nanoparticle systems in an application usually does not correspond to their original manufacturing process, the formulation of new or improved product properties is of decisive importance. The characterization of nanoparticles in complex formulations or matrices requires an adequate sample preparation based on an existing or yet to be developed Standard Operating Procedure (SOP). The structure of the SOPs includes the dispersion regulations, which are of essential importance for comparing reproducible results of nanoparticle measurement with respect to comparability and transferability worldwide. The aim is to separate and isolate relevant NMs with knowledge of the interrelationships.

Particulate products make up around 80% of chemical products, from all industry sectors. Examples given in this book include the construction materials, fine ceramics and concrete; the delicacies, chocolate and ice cream; pharmaceutical, powders, medical inhalers and sun screen; liquid and powder paints. Size distribution and the shape of the particles provide for different functionalities in these products. Some functions are general, others specific. General functions are powder flow and require – at the typical particulate concentrations of these products – that the particles cause adequate rheological behavior during processing and/or for product performance. Therefore, this book addresses particle packing as well as its relation to powder flow and rheological behavior. Moreover, general relationships to particle size are discussed for e.g. color and sensorial aspects of particulate products. Product-specific functionalities are often relevant for comparable product groups. Particle size distribution and shape provide, for example, the following functionalities: -       dense particle packing in relation to sufficient strength is required in concrete construction, ceramic objects and pharmaceutical tablets-       good sensorial properties (mouthfeel) to chocolate and ice cream-       effective dissolution, flow and compression properties for pharmaceutical powders-       adequate hiding power and effective coloring of paints for protection and the desired esthetical appeal of the objects-       adequate protection of our body against sun light by sunscreen-      effective particle transport and deposition to desired locations for medical inhalers and powder paints. Adequate particle size distribution, shape and porosity of particulate products have to be achieved in order to reach optimum product performance. This requires adequate management of design and development as well as sufficient knowledge of the underlying principles of physics and chemistry. Moreover, flammability, explosivity and other health hazards from powders, during handling, are taken into account. This is necessary, since great risks may be involved. In all aspects, the most relevant parameters of the size distribution (and particle shape) have to be selected.In this book, experts in the different product fields have contributed to the product chapters. This provides optimum information on what particulate aspects are most relevant for behavior and performance within specified industrial products and how optimum results can be obtained. It differs from other books in the way that the critical aspects of different products are reported, so that similarities and differences can be identified. We trust that this approach will lead to improved optimization in design, development and quality of many particulate products.

This book is devoted to the Discrete Element Method (DEM) technique, a discontinuum modelling approach that takes into account the fact that granular materials are composed of discrete particles which interact with each other at the microscale level. This numerical simulation technique can be used both for dispersed systems in which the particle-particle interactions are collisional and compact systems of particles with multiple enduring contacts. The book provides an extensive and detailed explanation of the theoretical background of DEM. Contact mechanics theories for elastic, elastic-plastic, adhesive elastic and adhesive elastic-plastic particle-particle interactions are presented. Other contact force models are also discussed, including corrections to some of these models as described in the literature, and important areas of further research are identified. A key issue in DEM simulations is whether or not a code can reliably simulate the simplest of systems, namely the single particle oblique impact with a wall. This is discussed using the output obtained from the contact force models described earlier, which are compared for elastic and inelastic collisions. In addition, further insight is provided for the impact of adhesive particles. The author then moves on to provide the results of selected DEM applications to agglomerate impacts, fluidised beds and quasi-static deformation, demonstrating that the DEM technique can be used (i) to mimic experiments, (ii) explore parameter sweeps, including limiting values, or (iii) identify new, previously unknown, phenomena at the microscale. In the DEM applications the emphasis is on discovering new information that enhances our rational understanding of particle systems, which may be more significant than developing a new continuum model that encompasses all microstructural aspects, which would most likely prove too complicated for practical implementation. The book will be of interestto academic and industrial researchers working in particle technology/process engineering and geomechanics, both experimentalists and theoreticians.

This edited volume presents most techniques and methods that have been developed by material scientists, chemists, chemical engineers and physicists for the commercial production of particulate materials, ranging from the millimeter to the nanometer scale.  The scope includes the physical and chemical background, experimental optimization of equipment and procedures, as well as an outlook on future methods. The books addresses  issues of industrial importance such as specifications, control parameter(s), control strategy, process models, energy consumption and discusses the various techniques in relation to potential applications.In addition to the production processes, all major unit operations and characterization methods are described in this book. It differs from other books which are devoted to a single technique or a single material. Contributors to this book are acknowledged experts in their field.The aim of the book is to facilitate comparison of the differentunit operations leading to optimum equipment choices for the production, handling and storage of particulate materials. An advantage of this approach is that unit operations that are common in one field of application are made accessible to other fields. The overall focus is on industrial application and the book includes some concrete examples. The book is an essential resource for students or researchers who work in collaboration with manufacturing industries or who are planning to make the switch from academia to industry.

This book addresses the properties of particles in colloidal suspensions. It has a focus on particle aggregates and the dependency of their physical behaviour on morphological parameters. For this purpose, relevant theories and methodological tools are reviewed and applied to selected examples. The book is divided into four main chapters. The first of them introduces important measurement techniques for the determination of particle size and interfacial properties in colloidal suspensions. A further chapter is devoted to the physico-chemical properties of colloidal particles—highlighting the interfacial phenomena and the corresponding interactions between particles. The book’s central chapter examines the structure-property relations of colloidal aggregates. This comprises concepts to quantify size and structure of aggregates, models and numerical tools for calculating the (light) scattering and hydrodynamic properties of aggregates, and a discussion on van-der-Waals and double layer interactions between aggregates. It is illustrated how such knowledge may significantly enhance the characterisation of colloidal suspensions. The final part of the book refers to the information, ideas and concepts already presented in order to address technical aspects of the preparation of colloidal suspensions—in particular the performance of relevant dispersion techniques and the stability of colloidal suspensions.

Particulate products make up around 80% of chemical products, from all industry sectors. Examples given in this book include the construction materials, fine ceramics and concrete; the delicacies, chocolate and ice cream; pharmaceutical, powders, medical inhalers and sun screen; liquid and powder paints. Size distribution and the shape of the particles provide for different functionalities in these products. Some functions are general, others specific. General functions are powder flow and require – at the typical particulate concentrations of these products – that the particles cause adequate rheological behavior during processing and/or for product performance. Therefore, this book addresses particle packing as well as its relation to powder flow and rheological behavior. Moreover, general relationships to particle size are discussed for e.g. color and sensorial aspects of particulate products. Product-specific functionalities are often relevant for comparable product groups. Particle size distribution and shape provide, for example, the following functionalities: -       dense particle packing in relation to sufficient strength is required in concrete construction, ceramic objects and pharmaceutical tablets-       good sensorial properties (mouthfeel) to chocolate and ice cream-       effective dissolution, flow and compression properties for pharmaceutical powders-       adequate hiding power and effective coloring of paints for protection and the desired esthetical appeal of the objects-       adequate protection of our body against sun light by sunscreen-      effective particle transport and deposition to desired locations for medical inhalers and powder paints. Adequate particle size distribution, shape and porosity of particulate products have to be achieved in order to reach optimum product performance. This requires adequate management of design and development as well as sufficient knowledge of the underlying principles of physics and chemistry. Moreover, flammability, explosivity and other health hazards from powders, during handling, are taken into account. This is necessary, since great risks may be involved. In all aspects, the most relevant parameters of the size distribution (and particle shape) have to be selected.In this book, experts in the different product fields have contributed to the product chapters. This provides optimum information on what particulate aspects are most relevant for behavior and performance within specified industrial products and how optimum results can be obtained. It differs from other books in the way that the critical aspects of different products are reported, so that similarities and differences can be identified. We trust that this approach will lead to improved optimization in design, development and quality of many particulate products.

This book is devoted to the Discrete Element Method (DEM) technique, a discontinuum modelling approach that takes into account the fact that granular materials are composed of discrete particles which interact with each other at the microscale level. This numerical simulation technique can be used both for dispersed systems in which the particle-particle interactions are collisional and compact systems of particles with multiple enduring contacts. The book provides an extensive and detailed explanation of the theoretical background of DEM. Contact mechanics theories for elastic, elastic-plastic, adhesive elastic and adhesive elastic-plastic particle-particle interactions are presented. Other contact force models are also discussed, including corrections to some of these models as described in the literature, and important areas of further research are identified. A key issue in DEM simulations is whether or not a code can reliably simulate the simplest of systems, namely the single particle oblique impact with a wall. This is discussed using the output obtained from the contact force models described earlier, which are compared for elastic and inelastic collisions. In addition, further insight is provided for the impact of adhesive particles. The author then moves on to provide the results of selected DEM applications to agglomerate impacts, fluidised beds and quasi-static deformation, demonstrating that the DEM technique can be used (i) to mimic experiments, (ii) explore parameter sweeps, including limiting values, or (iii) identify new, previously unknown, phenomena at the microscale. In the DEM applications the emphasis is on discovering new information that enhances our rational understanding of particle systems, which may be more significant than developing a new continuum model that encompasses all microstructural aspects, which would most likely prove too complicated for practical implementation. The book will be of interestto academic and industrial researchers working in particle technology/process engineering and geomechanics, both experimentalists and theoreticians.

The fluidized-bed reactor is the centerpiece of industrial fluidization processes. This book focuses on the design and operation of fluidized beds in many different industrial processes, emphasizing the rationale for choosing fluidized beds for each particular process. The book starts with a brief history of fluidization from its inception in the 1940’s. The authors present both the fluid dynamics of gas-solid fluidized beds and the extensive experimental studies of operating systems and they set them in the context of operating processes that use fluid-bed reactors. Chemical engineering students and postdocs as well as practicing engineers will find great interest in this book.