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Book Hydrodynamics and Mass Transfer in Downflow Slurry Bubble Columns

Download or read book Hydrodynamics and Mass Transfer in Downflow Slurry Bubble Columns written by Subrata Kumar Majumder and published by CRC Press. This book was released on 2019-01-02 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Slurry bubble column reactors are intensively used as a multiphase reactor in the chemical, biochemical, and petrochemical industries for carrying out reactions and mass transfer operations in which a gas, made up of one or several reactive components, comes into contact or reacts with a liquid. This volume describes the hydrodynamics of three-phase gas-liquid-solid flow in a downflow slurry bubble column. The efficiency of the downflow gas interacting system is characterized by the self-entrainment of secondary gas. The book covers the gas entrainment phenomena, gas holdup characteristics, pressure drop, gasliquid mixing characteristics, bubble size distribution, interfacial phenomena, and the mass transfer phenomena in the downflow slurry system. This volume will be useful in chemical and biochemical industries and in industrial research and development sectors, as well as in advanced education courses in this area. The book will be helpful for further understanding the multiphase behavior in gas interacting multiphase systems for research and development. The hydrodynamic and mass transfer characteristics discussed will be useful in the design and installation of the modified slurry bubble column in industry for specific applications.

Book Bubble Column Reactions

    Book Details:
  • Author : Wolf-Dieter Deckwer
  • Publisher : John Wiley & Sons
  • Release : 1992-04-08
  • ISBN :
  • Pages : 564 pages

Download or read book Bubble Column Reactions written by Wolf-Dieter Deckwer and published by John Wiley & Sons. This book was released on 1992-04-08 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: This technology, though used for many years, has shown great vitality recently and is still in a state of flux. Provides an account of developments up to the present and also an orderly evaluation of literature already published on the subject. Considerable space is devoted to bubble column reactor performance predictions based on mathematical models and the importance of each is explained with practical examples.

Book Hydrodynamics and Mass Transfer in Downflow Slurry Bubble Columns

Download or read book Hydrodynamics and Mass Transfer in Downflow Slurry Bubble Columns written by Subrata Kumar Majumder and published by CRC Press. This book was released on 2019-01-02 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Slurry bubble column reactors are intensively used as a multiphase reactor in the chemical, biochemical, and petrochemical industries for carrying out reactions and mass transfer operations in which a gas, made up of one or several reactive components, comes into contact or reacts with a liquid. This volume describes the hydrodynamics of three-phase gas-liquid-solid flow in a downflow slurry bubble column. The efficiency of the downflow gas interacting system is characterized by the self-entrainment of secondary gas. The book covers the gas entrainment phenomena, gas holdup characteristics, pressure drop, gasliquid mixing characteristics, bubble size distribution, interfacial phenomena, and the mass transfer phenomena in the downflow slurry system. This volume will be useful in chemical and biochemical industries and in industrial research and development sectors, as well as in advanced education courses in this area. The book will be helpful for further understanding the multiphase behavior in gas interacting multiphase systems for research and development. The hydrodynamic and mass transfer characteristics discussed will be useful in the design and installation of the modified slurry bubble column in industry for specific applications.

Book Bubbly Flows

    Book Details:
  • Author : Martin Sommerfeld
  • Publisher : Springer Science & Business Media
  • Release : 2012-12-06
  • ISBN : 3642185401
  • Pages : 354 pages

Download or read book Bubbly Flows written by Martin Sommerfeld and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book summarises the outcom of a priority research programme: 'Analysis, Modelling and Computation of Multiphase Flows'. The results of 24 individual research projects are presented. The main objective of the research programme was to provide a better understanding of the physical basis for multiphase gas-liquid flows as they are found in numerous chemical and biochemical reactors. The research comprises steady and unsteady multiphase flows in three frequently found reactor configurations, namely bubble columns without interiors, airlift loop reactors, and aerated stirred vessels. For this purpose new and improved measurement techniques were developed. From the resulting knowledge and data, new and refined models for describing the underlying physical processes were developed, which were used for the establishment and improvement of analytic as well as numerical methods for predicting multiphase reactors. Thereby, the development, lay-out and scale-up of such processes should be possible on a more reliable basis.

Book HYDRODYNAMIC MODELS FOR SLURRY BUBBLE COLUMN REACTORS  FINAL TECHNICAL REPORT ALSO INCLUDES THE QUARTERLY TECHNICAL REPORT FOR THE PERIOD 01 01 1997 03 31 1997

Download or read book HYDRODYNAMIC MODELS FOR SLURRY BUBBLE COLUMN REACTORS FINAL TECHNICAL REPORT ALSO INCLUDES THE QUARTERLY TECHNICAL REPORT FOR THE PERIOD 01 01 1997 03 31 1997 written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this study is to develop a predictive experimentally verified computational fluid dynamic (CFD) three phase model. It predicts the gas, liquid and solid hold-ups (volume fractions) and flow patterns in the industrially important bubble-coalesced (churn-turbulent) regime. The input into the model can be either particulate viscosities as measured with a Brookfield viscometer or effective restitution coefficient for particles. A combination of x-ray and[gamma]-ray densitometers was used to measure solid and liquid volume fractions. There is a fair agreement between the theory and the experiment. A CCD camera was used to measure instantaneous particle velocities. There is a good agreement between the computed time average velocities and the measurements. There is an excellent agreement between the viscosity of 800[micro]m glass beads obtained from measurement of granular temperature (random kinetic energy of particles) and the measurement using a Brookfield viscometer. A relation between particle Reynolds stresses and granular temperature was found for developed flow. Such measurement and computations gave a restitution coefficient for a methanol catalyst to be about 0.9. A transient, two-dimensional hydrodynamic model for production of methanol from syn-gas in an Air Products/DOE LaPorte slurry bubble column reactor was developed. The model predicts downflow of catalyst at the walls and oscillatory particle and gas flow at the center, with a frequency of about 0.7 Hertz. The computed temperature variation in the rector with heat exchangers was only about 5 K, indicating good thermal management. The computed slurry height, the gas holdup and the rate of methanol production agree with LaPorte's reported data. Unlike the previous models in the literature, this model computes the gas and the particle holdups and the particle rheology. The only adjustable parameter in the model is the effective particle restitution coefficient.

Book Experimental Characterization of Slurry Bubble column Reactor Hydrodynamics

Download or read book Experimental Characterization of Slurry Bubble column Reactor Hydrodynamics written by and published by . This book was released on 1997 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sandia's program to develop, implement, and apply diagnostics for hydrodynamic characterization of slurry bubble column reactors (SBCRs) at industrially relevant conditions is discussed. Gas liquid flow experiments are performed on an industrial scale. Gamma densitometry tomography (GDT) is applied to measure radial variations in gas holdup at one axial location. Differential pressure (DP) measurements are used to calculate volume averaged gas holdups along the axis of the vessel. The holdups obtained from DP show negligible axial variation for water but significant variations for oil, suggesting that the air water flow is fully developed (minimal flow variations in the axial direction) but that the air oil flow is still developing at the GDT measurement location. The GDT and DP gas holdup results are in good agreement for the air water flow but not for the air oil flow. Strong flow variations in the axial direction may be impacting the accuracy of one or both of these techniques. DP measurements are also acquired at high sampling frequencies (250 Hz) and are interpreted using statistical analyses to determine the physical mechanism producing each frequency component in the flow. This approach did not yield the information needed to determine the flow regime in these experiments. As a first step toward three phase material distribution measurements, electrical impedance tomography (EIT) and GDT are applied to a liquid solid flow to measure solids holdup. Good agreement is observed between both techniques and known values.

Book Population Balances

    Book Details:
  • Author : Doraiswami Ramkrishna
  • Publisher : Elsevier
  • Release : 2000-08-08
  • ISBN : 0080539246
  • Pages : 373 pages

Download or read book Population Balances written by Doraiswami Ramkrishna and published by Elsevier. This book was released on 2000-08-08 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: Engineers encounter particles in a variety of systems. The particles are either naturally present or engineered into these systems. In either case these particles often significantly affect the behavior of such systems. This book provides a framework for analyzing these dispersed phase systems and describes how to synthesize the behavior of the population particles and their environment from the behavior of single particles in their local environments. Population balances are of key relevance to a very diverse group of scientists, including astrophysicists, high-energy physicists, geophysicists, colloid chemists, biophysicists, materials scientists, chemical engineers, and meteorologists. Chemical engineers have put population balances to most use, with applications in the areas of crystallization; gas-liquid, liquid-liquid, and solid-liquid dispersions; liquid membrane systems; fluidized bed reactors; aerosol reactors; and microbial cultures. Ramkrishna provides a clear and general treatment of population balances with emphasis on their wide range of applicability. New insight into population balance models incorporating random particle growth, dynamic morphological structure, and complex multivariate formulations with a clear exposition of their mathematical derivation is presented. Population Balances provides the only available treatment of the solution of inverse problems essential for identification of population balance models for breakage and aggregation processes, particle nucleation, growth processes, and more. This book is especially useful for process engineers interested in the simulation and control of particulate systems. Additionally, comprehensive treatment of the stochastic formulation of small systems provides for the modeling of stochastic systems with promising new areas of applications such as the design of sterilization systems and radiation treatment of cancerous tumors. - A clear and general treatment of population balances with emphasis on their wide range of applicability. Thus all processes involving solid-fluid and liquid-liquid dispersions, biological populations, etc. are encompassed - Provides new insight into population balance models incorporating random particle growth, dynamic morphological structure, and complex multivariate formulations with a clear exposition of their mathematical derivation - Presents a wide range of solution techniques, Monte Carlo simulation methods with a lucid exposition of their origin and scope for enhancing computational efficiency - An account of self-similar solutions of population balance equations and their significance to the treatment of data on particulate systems - The only available treatment of the solution of inverse problems essential for identification of population balance models for breakage and aggregation processes, particle nucleation and growth processes and so on - A comprehensive treatment of the stochastic formulation of small systems with several new applications

Book Hydrodynamic Models for Slurry Bubble Column Reactors  Sixth Technical Progress Report

Download or read book Hydrodynamic Models for Slurry Bubble Column Reactors Sixth Technical Progress Report written by and published by . This book was released on 1996 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation is to convert the gas-solid-liquid fluidization model into a predictive design model. The IIT hydrodynamic model computes the phase velocities and the volume fractions of gas, liquid and particulate phases. Model verification involves a comparison of these computed velocities and volume fractions to experimental values. This report presents measurements of granular temperature of Air Products catalyst. The report is in the form of a preliminary paper, entitled ''Dynamics of Liquid-Solid Fluidized Beds with Small Catalyst Particles.'' The principal results are as follows: (1) For the liquid-solid system the granular temperature is much smaller than for a corresponding gas-solid system. This may be due to the larger viscosity of the liquid in comparison to air. (2) The collisional viscosity of the catalyst is correspondingly much smaller than that of catalyst particles in the air. (3) The dominant frequency of density oscillations is near two Hertz, as expected for a gas-solid fluidized bed. There exists a link between this low frequency and the high frequency of catalyst particle oscillations. The Air Products fluidized bed reactor is designed to produce methanol and synthetic fuels from synthesis gas.

Book Hydrodynamic Models for Slurry Bubble Column Reactor

Download or read book Hydrodynamic Models for Slurry Bubble Column Reactor written by and published by . This book was released on 1997 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation is to convert learning gas-solid-liquid fluidization model into a predictive design model. The IIT hydrodynamic model computes the phase velocities and the volume fractions of gas, liquid and particulate phases. Model verification involves a comparison of these computed velocities and volume fractions to experimental values. A paper ''Liquid-Solid Fluidization Using Kinetic Theory'' by D. Gidaspow and L. Huilin was presented at the Chicago ANNUAL AIChE meeting in November 1996. It will be published in the Symposium Series on Fluidization and Fluid Particle Systems. The authors have also computed the particle Reynolds stress for three-phase fluidization. Using an IIT Reflected Light Microscope they have determined the particle size distribution of the Air Products catalyst. The catalyst disintegrated during fluidization. They believe it is necessary to design a better catalyst . This can be done by finding an optimum particle size by considering difision and reaction in the catalyst and mixing resistance to mass transfer in the fluids. Their theory permits them to determine such an optimum particle size and best operating particle concentration.

Book ADVANCED DIAGNOSTIC TECHNIQUES FOR THREE PHASE SLURRY BUBBLE COLUMN REACTORS  SBCR

Download or read book ADVANCED DIAGNOSTIC TECHNIQUES FOR THREE PHASE SLURRY BUBBLE COLUMN REACTORS SBCR written by and published by . This book was released on 2000 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes the accomplishment made during the first year of this cooperative research effort between Washington University, Ohio State University and Air Products and Chemicals. A technical review of the variables affecting the SBCR performance, some aspects of bubble dynamics and hydrodynamics properties and physical properties of FT waxes and catalyst have been performed. The needed experimental facilities and measurement techniques have been evaluated and prepared. Exxon Norpar 14 has been suggested as a solvent to be used that mimics at room temperature and pressure up to 200 psi the hydrodynamics of FT waxes. A new correlation has been developed and tested to predict gas-liquid mass transfer coefficient at high pressure operation based on high pressure gas holdup and atmospheric data of gas-liquid mass transfer coefficient.

Book Hydrodynamics of Fischer Tropsch Synthesis in Slurry Bubble Column Reactors

Download or read book Hydrodynamics of Fischer Tropsch Synthesis in Slurry Bubble Column Reactors written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes studies on hydrodynamics of bubble columns for Fischer-Tropsch synthesis. These studies were carried out in columns of 0.051 m and 0.229 m in diameter and 3 m tall to determine effects of operating conditions (temperature and gas flow rate), distributor type (sintered metal plate and single and multi-hole perforated plates) and liquid media (paraffin and reactor waxes) on gas hold-up and bubble size distribution. In experiments with the Fischer-Tropsch (F-T) derived paraffin wax (FT-300) for temperatures between 230 and 280°C there is a range of gas velocities (transition region) where two values of gas hold-up (i.e., two flow regimes) are possible. Higher hold-ups were accompanied by the presence of foam (''foamy'' regime) whereas lower values were obtained in the absence of foam (''slug flow'' in the 0.051 m column, or ''churn-turbulent'' flow regime in the 0.229 m column). This type of behavior has been observed for the first time in a system with molten paraffin wax as the liquid medium. Several factors which have significant effect on foaming characteristics of this system were identified. Reactor waxes have much smaller tendency to foam and produce lower hold-ups due to the presence of larger bubbles. Finally, new correlations for prediction of the gas hold-up and the specific gas-liquid interfacial area were developed on the basis of results obtained in the present study. 49 refs., 99 figs., 19 tabs.

Book Experimental Techniques for Hydrodynamic Characterization of Multiphase Flows in Slurry phase Bubble column Reactors

Download or read book Experimental Techniques for Hydrodynamic Characterization of Multiphase Flows in Slurry phase Bubble column Reactors written by and published by . This book was released on 1994 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Slurry-phase bubble-column Fischer-Tropsch (FT) reactors are recognized as one of the more promising technologies for converting synthesis gas from coal into liquid fuel products (indirect liquefaction). However, hydrodynamic effects must be considered when attempting to scale these reactors to sizes of industrial interest. The objective of this program is to facilitate characterization of reactor hydrodynamics by developing and applying noninvasive tomographic diagnostics capable of measuring gas holdup spatial distribution in these reactors.

Book Sandia Support for PETC Fischer Tropsch Research

Download or read book Sandia Support for PETC Fischer Tropsch Research written by and published by . This book was released on 1996 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sandia's program to develop, implement, and apply diagnostics for hydrodynamic characterization of slurry bubble-column reactors (SBCRs) at industrially relevant conditions is discussed. Gas-liquid flow experiments are performed in an industrial-scale 48 cm ID stainless steel vessel. Gamma-densitometry tomography (GDT) is applied to make spatially resolved gas holdup measurements. Both water and Drakeol 10 with air sparging are examined at ambient and elevated pressures. Gas holdup increases with gas superficial velocity and pressure, and the GDT values are in good agreement with values from differential pressure measurements. Other diagnostic techniques are also discussed.

Book Hydrodynamic Models for Slurry Bubble Column Reactors  Third Technical Progress Report  January 1995  March 1995

Download or read book Hydrodynamic Models for Slurry Bubble Column Reactors Third Technical Progress Report January 1995 March 1995 written by and published by . This book was released on 1995 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation is to convert our {open_quotes}learning gas-solid-liquid{close_quotes} fluidization model into a predictive design model. The IIT hydrodynamic model computes the phase velocities and the volume fractions of gas, liquid and particulate phases. Model verification involves a comparison of these computed velocities and volume fractions to experimental values. After a discussion of our research with the DOE-Air Products team in January, we decided to concentrate on the slurry configuration of interest to DOE-Air Products which has no recirculation of liquid. In such a system the gas is the continuous phase, rather than the liquid that we had used in our model in the past. We have built such a cold flow two dimensional plastic model. We have also changed our computer code. At the request of Air Products and DOE we have started a simulation of LaPorte RUN E-8.1 (1991) for production of methanol as described in the Air Products report sent to us. For isothermal operation, there is good mixing, and the preliminary results shown in this report indicate that we should obtain an agreement between the experiment and the simulations. A final report will be prepared upon completion of the simulation.