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List Of Reviewers, Sang Done Kim

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

List of reviewers for this publication.

An Electrical Capacitance Tomography Study Of Pressurized Fluidized Beds, Niels G. Deen, Willem Godlieb, Sander Gorter, J.A.M. Kuipers

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

Simultaneous electrical capacitance tomography measurements for two planes were performed to obtain detailed information on bubble characteristics in a pressurized fluidized bed. Average permittivity values were used to get estimates of bubble sizes, while cross correlation was applied to the signals of both planes to obtain average bubble rise velocities.

At low pressures, a wide variation in bubble size was observed. Large stable bubbles tend to affect fluidization smoothness significantly. At higher pressure, bubbles possessed a more uniform size and were in general smaller. Consequently fluidization behavior was observed to be smoother at higher pressures.

Digital Image Analyis Of Bubble Flow Distribution – Influence Of Operational Parameters, Johanna Olsson, David Pallarès, Filip Johnsson

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

In a first step towards investigating the horizontal fuel mixing in fluidized bed (FB) boilers, this work applies digital image analysis to study the bubble flow properties in a 2-dimensional FB unit. The work investigates the influence of fluidization velocity, bed height and gas-distributor pressure drop on the volume fraction and horizontal distribution of bubbles.

Prediction Of Catalyst Attrition In An Industrial Fluidized Bed Plant Based On Lab Scale Attrition Tests, Ernst-Ulrich Hartge, Stefan Heinrich, Joachim Werther, Anja Püttmann, Andreas Thon, Gegory Patience, Richard Bockrath

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

The concept that catalyst attrition in a fluidized bed process can be simulated based on the attrition characteristics of the catalyst determined on labscale is applied to DuPont’s large scale process of maleic anhydride production from n-butane using a vanadium phosphorus oxide (VPO) catalyst. In the present cooperation effort the performance data and design parameters of the large scale plant are supplied by the École Polytechnique de Montréal and DuPont. At Hamburg University of Technology the catalyst’s attrition characteristics were determined in labscale attrition tests. Furthermore the fate of the solids in the process was simulated. The results of the …

Geldart Group Indication From Powder Measurements With A Rotating Drum Instrument, Clive Davies, Emile S. Webster

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

Data have been collected with a GDR, for powders from each Geldart Group, over a rotation rates in the range 0-22 r.p.m.. Composite plots of avalanching frequency ,slumping rate and rotation rate, show that power spectral density for Groups D and B is qute different from that observed for Groups A and C.

The Transport Disengagement Height (Tdh) In A Bubbling Fluidized Bed (Bfb), Chian Chan, Jonathan P.K. Seville, Jan Baeyens

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

Bubbles bursting at the surface of a BFB project particles into the freeboard. Coarser particles fall back, the solids loading declines with height in the freeboard, and fines are ultimately carried over. The height of declining solids loading is the TDH, measured in this research by Positron Emission Particle Tracking, and modeled from a balance of forces on ejected particles. Model predictions and PEPT-data are in good agreement. Empirical equations overestimate the TDH.

Investigation Of The Effect Of Fluidization Time On Electrostatic Charge Generation In Gas-Solid Fluidized Beds, Amanda Giffin, Andrew Sowinski, Poupak Mehrani

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

This work focused on determining the effect of the fluidization time on particle charging. Charge equilibrium was reached on the bed particles after 60 minutes. The wall particle layer was built with negative and positive charges. Similar sized particles migrated to each region of the bed regardless of fluidization time.

Effects Of Particle Size And Fluidizing Velocity On The Charge Density Of Entrained Fines, Xiaotao T. Bi, John Grace, Kwang Seok Choi, Muammar Omar

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

A previously-developed Faraday cup fluidized bed unit was modified to facilitate the in-situ monitoring of the transient entrainment rate and net charge of entrained fine powders. This enabled the determination of the transient charge density as a function of particle size and residence time of entrained fine particles. The results showed that the charge density increased significantly with increasing size of entrained fines, but was not very sensitive to the residence time and the fluidizing gas velocity for the finest entrained particles at gas velocities of 0.24 and 0.36 m/s. At Ug=0.48 m/s, the charge density of larger particles increased …

Electricity Generation Characteristics Of An Anaerobic Fluidized Bed Microbial Fuel Cell, Qingjie Guo, Shuju Zhao, Xuyun Wang, Xuehai Yue, Liangyu Hou

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

Anaerobic fluidized bed microbial fuel cell (AFBMFC) was developed to investigate the effect of fluidization behaviors on the electrogenesis capacity. Waste water and active carbon were used as liquid and solid phase, respectively. The fuel cell was started up successfully using anaerobic activated sludge as inoculums. The power density is increased with increasing circular liquid velocity up to 450 mW·m-2. High COD remove rate reached 93% after five days operation. Meanwhile, the effects of cathode area on the electrogenesis capacity of AFB MFC were also investigated.

Hydrodynamic Characteristics Of Liquid-Solid Fluidization Of Binary Mixtures In Tapered Beds, Sankarshana Talapuru Dr, J S N Murthy, S Nandana, Phani Kiran S V G R, V Ramesh

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

The problems associated with fluidization in cylindrical beds like entrainment of particles, limitation of operating velocity could be overcome by adopting tapered beds. There have been no systematic studies reported on fluidization behavior of binary mixtures wherein the effect of size ratio is considered on the hydrodynamic characteristics of liquid-solid fluidization in tapered beds. In the present work, an attempt has been made to study the fluidization behavior and hydrodynamic characteristics of liquid-solid fluidization of binary mixtures of size ratios ranging from 1.2 to 5.13 using sand of different sizes in tapered beds of apex angles 50, 100 and 150. …

Impact Behaviour Of Particles With Liquid Films: Energy Dissipation And Sticking Criteria, Sergiy Antonyuk, Stefan Heinrich, Stefan Palzer

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

The normal impact of spherical particles (elastic glass, elastic-plastic Al2O3) and non-spherical dominantly plastic agglomerates of amorphous maltodextrin on a wall with a liquid layer was studied. The objective was to investigate the effects of thickness (0.1-1 mm) and viscosity of the liquid layer (1-250 mPas) as well as of the impact velocity (1-3.0 m/s) of the granule on the restitution coefficient. The restitution coefficient was measured by using a free-fall apparatus. In the presence of a liquid layer, the higher the viscosity and thickness of the liquid layer the more the energy dissipated during impact and the smaller the …

Spinning Straw Into Gold: Turning Academic Papers Into Commercial Fluidized Bed Reactor Solutions, Charles O. Bolthrunis, Michael Hagan, Waheed A. Mukaddam

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

This paper presents an example of academic work that has been applied in industry. A case is presented of a solution to a serious operational problem involving fluidization phenomena threatening to cause structural damage to an operating chemical reactor. The process used to analyze the problem and arrive at a probable cause and design solutions are presented.

A Study On Denitrification In A Fluidized Bed Bioreactor, L. Prasanna Lakshmi, Y. Pydi Setty, K. Vimala

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

The work involves experimental investigation on biological denitrification in a fluidized bed reactor under anaerobic conditions using the microorganism Pseudomonas Stutzeri and plastic beads as fluidizing medium. The influence of various parameters like pH, initial nitrate concentration, Carbon/Nitrogen ratio, hydraulic retention time on nitrate-nitrogen removal rate from synthetic effluent prepared at the laboratory were studied in detail. The optimum operating conditions of pH, initial nitrate concentration, Carbon/Nitrogen ratio and flow rate obtained are 7.0–7.5, 15 mg/l, 1.5–2.0 and 4.41 x 10-5 m3/s respectively.

Chemical-Looping Steam Methane Reforming For Hydrogen Production In A Circulating Fluidized Bed Reactor, Sang Done Kim, Kang Seok Go, Young Wook Jeon, Chu Sik Park

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

Two-step steam methane reforming for hydrogen production using a chemical looping system is proposed to improve the conventional processes. The reaction characteristics with iron oxides as an oxygen carrier was determined in a circulating fluidized bed reactor. From this system, high concentrated hydrogen can be continuously produced without any post treatment.

The Hot Gas Desulfurization In A Compact Two Beds System Integrated With Coal Gasification And Fisher-Tropsch System, Young Cheol Park, Sung-Ho Jo, Seung-Yong Lee, Chang-Keun Yi

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

The hot gas desulfurization (HGD) technique is one of the elemental technologies of syngas purification having both thermal efficiency and very low emissions. The HGD is a novel method to efficiently remove H2S and COS in the syngas with regenerable sorbents at high temperature and high pressure condition. We propose a compact hot gas desulfurization system by which its operability is improved in stabilizing pressure balances among units. The proposed compact two beds system has two bubbling beds, solid injection nozzle, solid conveying line, and riser. The compact desulfurization system was located between coal gasifier and Fisher-Tropsch (F-T) reactor to …

A Novel Construction Of A Low-Pressure-Drop Air Nozzle Working With A 535mwe Cfb Boiler, Pawel Mirek, Wojciech Nowak, Marcin Klajny, Janusz Jabłoński

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

In the paper a novel construction of a low-pressure drop air-nozzle has been presented. It was designed in order to substitute the arrowhead nozzle working until now with a 535MWe CFB boiler. In comparison to the arrowhead nozzle the new construction has a lower pressure-drop and geometry, which is an effective barrier for backflow of a solid. In the paper numerical simulations as well as experimental studies of a new air nozzle have been presented. Laboratory tests have been conducted on a 3D test-stand equipped with six full scale air nozzles.

Development Of A Continuous Nanoparticle Coating With Electrospraying, N. Ellis, J. Ruud Van Ommen, C.U. Yurteri

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

Coating of micron-sized particles (host particles) with nanoparticles can result in modifying the surface properties of host particles leading to various applications. This work presents a novel concept of combining the electrospraying of nanoparticles onto the charged particles entrained out of the fluidized bed for developing a continuous coating process. By controlling the processes to effectively charge and contact particles using electric forces, we are able to fine-tune the properties of the obtained nano-coated particles.

Experimental And Computational Study On The Bubble Behavior In A 3-D Fluidized Bed With A Vertical-Axis, Rotating Distributor, Antonio Acosta Iborra, F. Hernández-Jiménez, C. Sobrino, M. De Vega

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

This work presents experimental measurements in a three-dimensional fluidized bed equipped with a novel vertical-axis, rotating distributor, together with two-fluid (Eulerian-Eulerian) CFD simulation results. The influence of the distributor rotation on the behavior of the bubbles in the experiments and in the CFD results is compared and critically analyzed.

Hydrodynamics On Chemical Looping Combustion Using Multiphase Cfd With Kinetic Theory Of Granular Flow, Jonghwun Jung, Isaac K. Gamwo

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

The fundamental knowledge of multiphase reactive hydrodynamics of the gassolid flow is essential for the design, optimization, and operation of industrial reactors. The multiphase computational fluid dynamics (CFD) model with the kinetic theory of granular flow, MFIX, developed earlier at the National Energy Technology Laboratory have been adapted to describe a fuel reactor of chemical looping combustion (CLC) processes. To understand hydrodynamics the chemical kinetics and mass transfer in the fuel reactor have been developed, where the reduction reaction is the first order of methane gas and the oxygen in metal oxygen carriers transfer to gas phase. The fuel conversion …

A Novel Chemical Looping Combustion Process: Pressure Drop And Solid Circulation Rate Modelling, Ali Hoteit, Yazdanpanah Mohammad-Mahdi, Forret Ann, Delebarre Arnaud, Gauthier Thierry

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

Experimental results from a cold flow unit of a novel chemical looping combustion configuration are presented in this paper. The system employs a non-mechanical lvalve to control solid flow rate and uses loop-seals to minimize gas leakage. A model was developed to predict solid flow rate and pressure variation in different elements of the system. The developed model was able to well predict solid flow rate within an error range of 10% for a wide solid flux range of 70 – 150 kg/m².s. Sensibility of the solid flow rate was analyzed for different operating parameters by aid of the model. …

Reaction Characteristics Of Two Water Gas Shift Catalysts In A Bubbling Fluidized Bed Reactor For Sewgs Process, Ho-Jung Ryu, Sung-Ho Jo, Young Cheol Park, Chang-Keun Yi

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

Reaction characteristics of two WGS catalysts for SEWGS process were investigated in a bubbling fluidized bed reactor. The commercial low temperature WGS catalyst produced by Süd-chemie and new catalyst produced by spray-drying method were used as bed materials. Reaction temperature, steam/CO ratio, and gas velocity were considered as experimental variables. Moreover, long-term operation results of two WGS catalysts were compared as well.

Decay Factor With Experimental Variables In Two Circulating Fluidized Bed (Cfb) Risers, Donghyun Lee, Hyun Suk Lee, Jong Hun Lim, Sang Soon Park, Ho Jeong Chae, Soon Yong Jeong

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

The effects of the riser inlet velocity, solid mass flux and particle size on the axial solid holdup profile and decay factor were investigated using two circulating fluidized beds (CFBs) with FCC (Geldart A) particles as the bed materials. Based on the experimental results from the two-CFBs, the axial solid holdup in the two CFBs were compared with the correlations of previous studies. Also, an empirical correlation was proposed for decay factor that exhibited a good agreement with experimental data.

Flow Behaviors In A High Solid Flux Circulating Fluidized Bed Composed Of A Riser, A Downer And A Bubbling Fluidized Bed, A. Tsutsumi, Guoqing Guan, Chihiro Fushimi, Masahiro Ikeda, Yu Nakamura, Toshiyuki Suda, Masanori Ishizuka, Hiroyuki Hatano, Satoru Matsuda, Yoshizo Suzuki

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

A circulating fluidized bed coal gasifier cold model which consists of an acrylic riser, a downer, and a bubbling fluidized bed were set up. Flow behaviors were investigated using silica sand with the solid mass flux up to 336 kg/m2•s. The effects of the solid inventory and the seals between the three reaction zones on the solid mass flux were investigated and discussed.

The Effects Of Distributor Design On The Solids Distribution In A Cfb Riser, Jesse Zhu, Jing Xu, Botao Peng, Chao Zhang

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

The influence of gas distributor design on the gas-solids flow structure was investigated in a rectangular CFB riser. The gas distributor was altered five different ways. The results show that the distributor design had significant effects on the solids distribution. The changed flow structure was maintained from the entrance to the riser top. Altering the gas distributor was an effective and practical method to change the flow structure. This study may be beneficial to CFB design and operation.

Co-Combustion Of Korean Anthracite With Various Fuels In A Commercial Circulating Fluidized Bed Boiler, Jong-Min Lee, Dong-Won Kim, Pyeong-Ki Seon, Jae-Sung Kim

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

The effect of co-combustion of various fuels such as bituminous coal, imported anthracite, RDF and wood pellet with Korean anthracite on the combustion and environmental performance was observed in the commercial CFB boiler. The temperatures in the furnace and cyclones exits decreased with increasing the cocombustion ratio of the bituminous coal, which could achieve more stable operation of the CFB boiler. During Co-combustion of the RDF and wood pellets, the temperature of the furnace exit increased slightly with due to volatiles re-combustion which could restrict to increase the co-combustion ratio of the RDF and wood pellets in the CFB boiler. …

The Influence Of Particle Attrition On Sorbent Inventory And Particle Size Distribution In Air-Blown Circulating Fluidized Bed Combustors, Piero Salatino, Fabio Montagnaro, Fabrizio Scala, Massimo Urciuolo

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

This paper presents a population balance model aiming at the prediction of sorbent inventory and particle size distribution establishing at steady state in the bed of an air-blown circulating fluidized bed combustor fuelled with a sulphur-bearing solid fuel. The core of the model is represented by population balance equations on sorbent particles which embody terms expressing the extent/rate of sorbent attrition/fragmentation. The effect of the progress of sulphation on attrition and fragmentation is taken into account by selection of appropriate constitutive equations. Model results are presented and discussed with the aim of clarifying the influence of particle attrition/fragmentation on sorbent …

Gas-Solid Fluidization In A Microfluidic Channel, Fei Wang, L S Fan

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

Experimental studies using a high speed digital camera are conducted to examine gas-solid fluidization in microfluidic channels (3mmX3mm and 2mmX3mm). The experimental results indicate the significant channel wall effects on the hydrodynamic properties including bed expansion and regime transition velocities. These properties are analyzed and discussed in the context of correlation equations reported for large fluidized beds.

Characterization Of Turbulent Regime Behavior In The Dilute Zone Of A Circulating Fluidized Bed Riser, Abdelghafour Zaabout, Hervé Bournot, René Occelli, Bousselham Kharbouch

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

This study consists in characterizing the solid phase behavior in the dilute region of a circulating fluidized bed riser (CFB) for the turbulent regime (i.e. for superficial gas velocities Uc

Effect Of Distributor Design On Solids Circulation And Gas Bypass In An Internal Circulating Fluidized Bed Reactor, Xiaotao T. Bi, Terris T. Yang

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

The effect of the distributor design on the gas bypass and solids circulation was investigated for the flat, cylindrical and conical gas distributors in a cold model internal circulating fluidized bed to provide design and operating criteria for the future application of ICFB deNOx reactor. A high gas bypass ratio from the annulus to draft tube and low from the draft tube to annulus were identified for all tested distributors. The solids circulation rates increased with the increase of both annulus and draft tube gas velocities, where the conical distributor exhibited a more flexible and stable operation. The particle size …

Aeration And Mixing Behaviours Of Binary Mixtures Of Nano-Sized Powders Under Sound Vibration, Paola Ammendola, R. Chirone

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

The aeration behaviour of three different nano-sized powders, Al2O3, Fe2O3 and CuO, fluidized under the application of acoustic fields of different intensities (125-150 dB) and frequencies (50-300 Hz) has been characterized. The characterization of the fluidization of binary mixtures of Al2O3 and Fe2O3 has been also investigated under the application of acoustic fields of 120 Hz and of two different intensities, 130 and 135 dB, and varying the relative amount of two powders from 17 to 50 %wt of Fe2O3. The addition of Fe2O3 has a beneficial effect on fluidization quality of Al2O3 even for the lowest amount of Fe2O3. …