Fluidization refers to a process by which a fluid like state is imparted to granular solid particles by the passing of a fluid upwards through the bed of particles. A semi fluidized bed is characterized by a fluidized bed and a packed bed in a series within a single contacting vessel. Gas-liquid-solid semi fluidization is defined as an operation in which a bed of solid particles is suspended in gas and/or liquid upward flowing media due to the net gravitational force on the particles and the motion of the particles is restricted by a top restraint. Such an operation generates intimate contact between the gas, liquid and solid particles in these systems and provides substantial advantages for applications in physical, Chemical and biochemical processing involving gas, liquid and solid phases. The experiments were conducted using liquid as the continuous phase and gas as the discontinuous phase. In this work air, water and dolomite (2.31mm, and 1.7mm) are used as the gas, liquid and solid phases respectively. The experiments were carried out in a 100 mm ID of 2m height vertical Plexiglas column. Knowledge of minimum liquid semi fluidization velocity is essential for the successful operation of gas-liquid-solid semi fluidized beds. Bed pressure measurements have been made to predict the values of the minimum liquid semi fluidization velocity. In the present work, hydrodynamic characteristics viz., the pressure drop, bed expansion of a co-current gas-liquid-solid semi fluidized bed has been studied. These have done in order to develop a good understanding of each of the flow regime in gas-liquid and liquid-solid semi fluidization. The effect of static bed height, particle size, liquid velocity and gas velocity on hydrodynamics parameters like minimum semi fluidization velocity, pressure drop, expansion ratio have been investigated. Experimental study based on statistical design has been made to investigate the expansion ratio of semi fluidized bed. The experimental val.

Since the pioneering text by Mathur and Epstein over 35 years ago, much of the work on this subject has been extended or superseded, producing an enormous body of scattered literature. This edited volume unifies the subject, pulling material together and underpinning it with fundamental theory to produce the only complete, up-to-date reference on all major areas of spouted bed research and practice. With contributions from internationally renowned research groups, this book guides the reader through new developments, insights and models. The hydrodynamic and reactor models of spouted and spout-fluid beds are examined, as well as such topics as particle segregation, heat and mass transfer, mixing and scale-up. Later chapters focus on drying, particle-coating and energy-related applications based on spouted and spout-fluid beds. This is a valuable resource for chemical and mechanical engineers in research and industry.

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.

Fluid Bed Technology in Materials Processing comprehensively covers the various aspects of fluidization engineering and presents an elaborate examination of the applications in a multitude of materials processing techniques. This singular resource discusses: All the basic aspects of fluidization essential to understand and learn about various techniques The range of industrial applications Several examples in extraction and process metallurgy Fluidization in nuclear engineering and nuclear fuel cycle with numerous examples Innovative techniques and several advanced concepts of fluidization engineering, including use and applications in materials processing as well as environmental and bio-engineering Pros and cons of various fluidization equipment and specialty of their applications, including several examples Design aspects and modeling Topics related to distributors effects and flow regimes A separate chapter outlines the importance of fluidization engineering in high temperature processing, including an analysis of the fundamental concepts and applications of high temperature fluidized bed furnaces for several advanced materials processing techniques. Presenting information usually not available in a single source, Fluid Bed Technology in Materials Processing serves Fluidization engineers Practicing engineers in process metallurgy, mineral engineering, and chemical metallurgy Researchers in the field of chemical, metallurgical, nuclear, biological, environmental engineering Energy engineering professionals High temperature scientists and engineers Students and professionals who adopt modeling of fluidization in their venture for design and scale up

This reference details particle characterization, dynamics, manufacturing, handling, and processing for the employment of multiphase reactors, as well as procedures in reactor scale-up and design for applications in the chemical, mineral, petroleum, power, cement and pharmaceuticals industries. The authors discuss flow through fixed beds, elutriation and entrainment, gas distributor and plenum design in fluidized beds, effect of internal tubes and baffles, general approaches to reactor design, applications for gasifiers and combustors, dilute phase pneumatic conveying, and applications for chemical production and processing. This is a valuable guide for chemists and engineers to use in their day-to-day work.

The Multiphase Flow Handbook, Second Edition is a thoroughly updated and reorganized revision of the late Clayton Crowe’s work, and provides a detailed look at the basic concepts and the wide range of applications in this important area of thermal/fluids engineering. Revised by the new editors, Efstathios E. (Stathis) Michaelides and John D. Schwarzkopf, the new Second Edition begins with two chapters covering fundamental concepts and methods that pertain to all the types and applications of multiphase flow. The remaining chapters cover the applications and engineering systems that are relevant to all the types of multiphase flow and heat transfer. The twenty-one chapters and several sections of the book include the basic science as well as the contemporary engineering and technological applications of multiphase flow in a comprehensive way that is easy to follow and be understood. The editors created a common set of nomenclature that is used throughout the book, allowing readers to easily compare fundamental theory with currently developing concepts and applications. With contributed chapters from sixty-two leading experts around the world, the Multiphase Flow Handbook, Second Edition is an essential reference for all researchers, academics and engineers working with complex thermal and fluid systems.

Since the publication of the first edition of Multiphase Flow with Droplets and Particles, there have been significant advances in science and engineering applications of multiphase fluid flow. Maintaining the pedagogical approach that made the first edition so popular, this second edition provides a background in this important area of fluid mecha

The field of multiphase flows has grown by leaps and bounds in the last thirty years and is now regarded as a major discipline. Engineering applications, products and processes with particles, bubbles and drops have consistently grown in number and importance. An increasing number of conferences, scientific fora and archived journals are dedicated to the dissemination of information on flow, heat and mass transfer of fluids with particles, bubbles and drops. Numerical computations and "thought experiments" have supplemented most physical experiments and a great deal of the product design and testing processes. The literature on computational fluid dynamics with particles, bubbles and drops has grown at an exponential rate, giving rise to new results, theories and better understanding of the transport processes with particles, bubbles and drops. This book captures and summarizes all these advances in a unified, succinct and pedagogical way. Contents: Fundamental Equations and Characteristics of Particles, Bubbles and Drops; Low Reynolds Number Flows; High Reynolds Number Flows; Non-Spherical Particles, Bubbles and Drops; Effects of Rotation, Shear and Boundaries; Effects of Turbulence; Electro-Kinetic, Thermo-Kinetic and Porosity Effects; Effects of Higher Concentration and Collisions; Molecular and Statistical Modeling; Numerical Methods-CFD. Key Features Summarizes the recent important results in the theory of transport processes of fluids with particles, bubbles and drops Presents the results in a unified and succinct way Contains more than 600 references where an interested reader may find details of the results Makes connections from all theories and results to physical and engineering applications Readership: Researchers, practicing engineers and physicists that deal with any aspects of Multiphase Flows. It will also be of interest to academics and researchers in the general fields of mechanical and chemical engineering.

During a century, from the Van der Waals mean field description (1874) of gases to the introduction of renormalization group (RG techniques 1970), thermodynamics and statistical physics were just unable to account for the incredible universality which was observed in numerous critical phenomena. The great success of RG techniques is not only to solve perfectly this challenge of critical behaviour in thermal transitions but to introduce extremely useful tools in a wide field of daily situations where a system exhibits scale invariance. The introduction of scaling, scale invariance and universality concepts has been a significant turn in modern physics and more generally in natural sciences. Since then, a new "physics of scaling laws and critical exponents", rooted in scaling approaches, allows quantitative descriptions of numerous phenomena, ranging from phase transitions to earthquakes, polymer conformations, heartbeat rhythm, diffusion, interface growth and roughening, DNA sequence, dynamical systems, chaos and turbulence. The chapters are jointly written by an experimentalist and a theorist. This book aims at a pedagogical overview, offering to the students and researchers a thorough conceptual background and a simple account of a wide range of applications. It presents a complete tour of both the formal advances and experimental results associated with the notion of scaling, in physics, chemistry and biology.