Advances in GasLiquidSolid Fluidization

1
Advances in Gas-Liquid-Solid Fluidization

• By
• L.-S. Fan
• Department of Chemical Engineering
• The Ohio State University

2
Acknowledgements

• PhD students
• D. Arters, F. Bavarian, L. Beaver, S.H. Chern, Z.
  Cui, Y. Ge, S.J. Hwang, R.H. Jean, P.J. Jiang, B.
  E. Kreischer, S. Kumar, R. Lau, E. Lee, S.C.
  Liang, T.J. Lin, X. Luo, A. Park, J. Reese, G.H.
  Song, W.T. Tang, K. Tsuchiya, J.W. Tzeng, L.
  Velazquez, K. Wisecarver, G.Q. Yang, J.P. Zhang
• Post Doctoral Associates
• F. Bavarian, R.-C. Chen, X. Chen, Y.M. Chen, G.
  Evans, K. Fujie, T. Hong, R.H. Jean, P.J. Jiang,
  T. Kawamura, K. Kitano, R. Lau, Y. P. Lee, T.R.
  Long, A. Matsuura, T. Miyahara, H. Moritomi, R.
  Mudde, K. Muroyama, K. Tsuchiya, A. Tsutsumi,
  J.W. Tzeng, W. Watsito, L. Yong, J.P. Zhang, J.
  Zhang
• Sponsors
• Air Product, Amoco, BP, Conoco, Chevron, DuPont,
  ENI-Snamprogetti, Exxon, HRI, IFP, Sasol, Shell,
  Statoil, Texaco, DOE, NSF

3
(No Transcript)
4
(No Transcript)
5
Scopes

• Industrial applications and challenges
• Fundamental characteristics (particle-particle,
  particle-bubble and particle-droplet
  interactions, bubble wake, turbulence and flow
  structure)
• Pressure effects
• Discrete Computation of Gas-Liquid-Solid
  Fluidization
• Other topics (magnetic and acoustic field effect
  and particle charges)

6
Industrial Applications

• Physical Processing dust collection, air
  flotation, air humidification, three-phase flow,
  etc.
• Chemical, Petrochemical or Electrochemical
  Processing hydrogen peroxide production,
  hydrotreating and conversion of petroleum resids,
  heavy oils and synthetic crudes from coal, oil
  shales and tar sands, flue gas desulfurization,
  electrodes, etc.
• Biochemical Processing wastewater treatment,
  antibiotics production, etc.

7

• Major commercial technology developments using
  three-phase fluidization (TF) reactor systems in
  next five years would directly be associated with
  those involving natural gas conversion to
  liquid-phase products such as paraffin and olefin

Couvaras, Petroleum Economist 2003
8
A Chemical and Petrochemical Application
Production of Methanol and Dimethyl Ether

• CO 2H2 ? CH3OH (1)
• 2CH3OH ? CH3OCH3 H2O (2)
• CO H2O ? CO2 H2 (3)
• Overall 3CO 3 H2 ? CH3OCH3 CO2 (4)

Catalyst 1
Catalyst 2
Catalyst 1

• Overall reaction is controlled by reaction (1)
  and the operating strategy depends on the H2/CO
  ratio (0.5-3) in the feedstock from coal
  gasification or natural gas reforming
• The gas stream needs to minimize the presence of
  CO2 to promote reaction (3)
• The CO-rich feedstock yields good synergistic
  effect in terms of dehydration reaction in
  reaction (3)
• The Catalyst activity and deactivation effect are
  important to overall kinetics based on the type
  of feedstock

9

• Reactions are exothermic. The TF reactor systems
  provide good liquid mixing, and heat transfer
  effects that allow the reactions to take place
  under the CO-rich condition, thereby enhancing
  the reactant conversions. The TF could readily
  accommodate a varied feedstock with respect to
  the H2/CO ratio with tailored quantity of
  catalysts to be used for the reactor.

10

• Issues on reactor operation
• Weeping in distributor and distributor design

Slurry bubble column
Capacitance Number
11
Orifice size and liquid property effects on
weeping velocity
Pressure effects on weeping velocity
12
Moving Packed Bed Phenomenon in Commercial
Reactors
Saberian-Broudjenni et al, 1984 first reported a
similar phenomenon in an ambient system. Bavarian
and Fan, 1991 explained this phenomenon
13

• Scale up issues (for Fischer-Tropsch Synthesis)
• Scale up from 5 m ID to 10 m ID
• Complex scale up slurry reactor (small particles)
  compared to fluidized bed reactor (large
  particles)
• Configuration and mechanical arrangement of heat
  exchangers
• L/D ratio (2-5) and its effect on hydrodynamics
• Comparison with gas-solid fluidized bed system
• Advantage of producing large molecular weight
  products using slurry reactor over gas-solid
  turbulent or circulating fluidized bed reactor

Sasols 5m Slurry Phase Reactor in Sasolburg for
gas conversion to liquid
14
Biochemical Applications

• Generally applied for processing of large liquid
  throughflows (wastewater treatment), for
  continuous cultures, or for mass production of
  usually lower value products
• Solids carrier for cell immobilization
• Physiology and functions of immobilized cells
  under aerobic and anaerobic conditions
• Bubble agitation and fluid shear effect on cell
  immobilization methods and biofilm development
• Substrate and/or oxygen mass transfer limitation
  on immobilized cell particles

Ebaras commercial three-phase bioreactor for
paper pulp wastewater treatment 4m (w) X 7m (l)
X 9m (h) X 3 cells
15
Fundamental Characteristics

• Particle-particle collision
• Particle-bubble collision
• Particle-liquid droplet collision
• Bubble wake
• Turbulence
• Flow structure
• Discrete Simulation

16
Particle-particle collision
Microlayer Model

• Continuity

• Momentum

• The pressure distribution in the microlayer

• If Reh ltlt 1, the equation above can be written as

?1220 kg/m3 µ0.053 kg/ms dp1.27 cm
?p2180 kg/m3
This is the well known result from the
lubrication theory
17
Experimental Data
Hard sphere model without approaching interaction
Hard sphere model with approaching interaction

Complete collision model with compression and
rebound
Pressure contour
Comparison between Simulated and Experimental
Results
18
Particle-Bubble Collision
19
Deformed doughnut-shape bubble upon particle
collision
20
Modes of Droplet-Particle Collision in the Nozzle
Injection
21
Temperature field
Water droplet collision with moving particle with
temperature of 400C.  dp 3mm, initial velocity
of particle 25cm/s, We 15, Ddrop 2.4mm,
initial velocity of drop 25cm/s, obliquity
0.5mm.
Water droplet impact on the quartz surface with
462 oC. We (?u2D/?) 68, droplet diameter (D)
4.7 mm (experimental images from Groendes and
Mesler, 1982).
22
(No Transcript)
23
Bubble Wake
Fan and Tsuchiya Bubble Wake Dynamics in Liquids
and Liquid Solid Suspensions, Butterworths,
1990.
Bed Contraction

• Massimilla et al. (1959) first reported this
  phenomenon.
• Bhatia and Epstein (1974) generalized wake model
  quantifies this phenomenon

24
History of single bubble event particle
traveling with bubble in primary wake
25
(No Transcript)
26
(No Transcript)
27
Estimation of apparent effective viscosity of
water-sand particle bubble size based on (a) 3-D
and (b) 2-D data.
Shear-thinning behavior of water-sand particle
fluidized bed.
28
(No Transcript)
29
Flow structure in the vortical-spiral flow regime
in 3-D gas-liquid bubble column (Franz et al.,
1984)
Radial vs. axial displacement for descending
radioactive particle (Larachi et al. 1996)
Flow structure in the vortical-spiral flow regim
in a 3-D gas-liquid bubble column and
gas-liquid-solid fluidization system (Chen et
al., 1994)
Liquid flow field at the plane of 0.75 radius in
a gas-liquid bubble column system (Chen et al.,
1994)
30
Particle Image Velocimetry (Chen and Fan, 1992)
Advance Diagnostic Techniques
Computer-automated radioactive particle tracking
(CARPT) (Luo et al, 2003)
Computer Tomography (CT) (Chaouki et al., 1997
Ultrasonic computed tomography (Warsito et al.,
1999)
Gamma-Densitometry Tomography and
Electrical-Impetence Tomography (George et al.,
2001)
31
Hopfield Network
Image reconstruction Cq(f) Image
32
ECT Studies on a 12" turbulent fluidized bed
3-D Reconstruction of Model Sphere and Gas-Solid
Turbulent Fluidized Bed at Ug 1m/s
33
Flow structures and gas holdup distributions in
G-L-S system
Z 20 cm
Gas concentration
34
Flow structures and gas and solid holdup
distributions in G-L and G-L-S systems
Z 20 cm
Ug 15 cm/s
35
Principle of 3-D Bubble Image Velocimetry
3-D Cross-correlation
V 3-D interrogation domain V0 interrogation
volume
Correlation function
36
Bubble plume central position fluctuations and
time-averaged bubble plume central position in
G-L-S fluidized bed
Gas air Liquid Norpar Solid 200?m
glass beads
37
Bubble Induced Turbulence
u
tb10ms
Measurement volume
v
Bubble
LDV results of a single bubble chain db 6 mm
Db, ub
PIV result
ltuw gt ub
Wake
ltugt gtgt ltvgt
uw uw - ltuwgt
u ltugt u
v ltvgt v
ltuugtw
vw ? vw
Subscript w wake
Diagram of bubble wake turbulence measurements
38
1- Energy containing range 2- Inertial range
3- Energy containing range for shear-induced
turbulence 4-Inertial range for shear-induced
turbulence 5- Energy containing range for
bubble-induced turbulence 6- Inertial range for
bubble-induced turbulence.
4
2
Measurement Points
3
1
1
Slope -5/3
Gas
6
5
Power spectra in the liquid phase in the central
and wall regions in a bubble column h 5 cm
39
Shear induced energy containing range
Bubble induced energy containing range
Bubble induced inertial range
Measurement Points
Measurement Points
Gas
Gas
H 3 cm, 2-orifice distributor
Liquid phase turbulence power spectra Ug 2.25
cm/s, h 5 cm, single nozzle used
Contribution of bubble-induced and shear-induced
turbulence in gas-liquid system
40
Power Spectra in Gas-Liquid-Solid Systems
-5/3
Measurement Points
Gas
Power spectra in gas, liquid and solid phases
with single nozzle used Ug 7.5 cm/s, h 5 cm
41
Left Schematic diagram of the flow
system Upper-Right 4 ID high pressure (22MPa)
and high temperature (200oC) flow visualization
column Lower-Right High pressure gas cylinder
trailer
42
(No Transcript)
43
Liquid Paratherm NF Heat Transfer Fluid Solid
Glass Beads (dp 2.1 mm, ?p2513 kg/m3
Experimental data Chitester et al. (1984) Grace
(1982) Richardson (1971) Wen and Yu (1966) Inst.
Gas Tech. (1978)
T 60oC
umf103 (m/s)
T 32.5oC
Pressure (MPa)

44
Comparison of Gas Holdup Data
Nitrogen-Paratherm-Alumina 90mm 0.1016m ID
Gas Holdup
Nitrogen-Paratherm-Alumina (90mm) 0.1016m ID
Gas Holdup
Tarmy et al., 1984
45

• Maximum Stable Bubble Size (Internal Circulation
  Model)

Model considers a large ellipsoidal bubble
rising in a stagnant liquid/slurry, at the
absence of stresses in the liquid/slurry
phase. Bubble surface
Internal circulation described by Hills vortex
(1894)
rc - component
z - component
Aspect ratio of bubble, a
46

• Maximum Stable Size (continued)

Centrifugal force in x direction rate of change
of momentum in the x direction across the surface
S.
Surface tension force
Bubble breakup criterion centrifugal force
overcomes suffice tension force.
Maximum stable bubble size
47
Internal circulation model - Experimental
confirmation of breakup mechanism
Bubble breakup sequence (P 3.5 MPa)
0 ms 17 ms 34 ms 51 ms 68 ms
Maximum bubble size
48
Delnoij et al., 1997
Two/Three-Fluid Model Computation for
Gas-Liquid/Gas-Liquid-Solid Fluidized Bed
Reactors (e.g., Delnoij et al., 1997
Mitra-Majumdar et al., 1998 Sokolichin and
Eigenberger, 1999 Pan et al., 1999 Lapin et
al., 2001 Pfleger and Becker, 2001 Buwa and
Ranade, 2002 Matonis et al, 2003)
Pan et al., 1999
Buwa and Ranade, 2002
49
Discrete Computation Key Equations

• Continuous Phase

• Inter-Phase Forces

Bubble-fluid surface tension force
(Brackbill et al,1992)
Volumetric particle-fluid interaction force

• Smagorinsky Sub-Grid Stress Model

Added mass force
Drag force

• Level-set method for bubble interface tracking

• Particle Motion Equation

and
50
Liquid density (kg/m3) 1000 Liquid
viscosity (Pa?s) 0.01 Surface tension (N/m)
0.0728 Gas density (kg/m3) 1.1 Diameter
of bubble (cm) 0.8 Grid size (cm)
0.05
51
Level Set Simulation Air bubble formation
in water
Liquid density (kg/m3) 1000 Liquid
viscosity (Pa?s) 0.01 Surface tension
(N/m) 0.0728 Gas density (kg/m3)
1.1 Diameter of nozzle (cm) 0.4 Grid
size (cm) 0.025 Nozzle gas
velocity (cm/s) 10.0
52
Multi-Nozzle Simulation Air-NF
Liquid density (kg/m3) 868 Liquid viscosity
(Pa?s) 0.2673 Surface tension (N/m)
0.0292 Gas density (kg/m3) 1.1 Diameter of
nozzle (cm) 4X0.4 Nozzle gas velocity
(cm/s) 10.0 Grid size (cm) 0.2
53
Gas-Liquid-Solid Fluidization
Liquid density (kg/m3) 868 Liquid
viscosity (Pa?s) 0.2673 Surface tension
(N/m) 0.0292 Gas density (kg/m3)
1.1 Particle density (kg/m3) 2500 Diameter
of particle (cm) 0.08/2000 Diameter of nozzle
(cm) 0.4 Liquid velocity (cm/s)
4.0 Grid size (cm) 0.2
54
Gas-Liquid-Solid Fluidization
Liquid density (kg/m3) 868 Liquid viscosity
(Pa?s) 0.02673 Surface tension (N/m)
0.0292 Gas density (kg/m3) 1.1 Particle
density (kg/m3) 2500 Diameter of particle (cm)
0.06/4000 Diameter of nozzle (cm) 0.4 Liquid
velocity (cm/s) 2.0 Nozzle gas velocity (cm/s)
10
55
Other Topics
Magnetically Three-Phase Fluidized Bed (van
Willigen and Brugghenstraat, 2001)
Magnetic field gradient can create sufficient
magnetic force acting upon the ferromagnetic
particles to replace or supplement the
gravitational force. Therefore, the ferromagnetic
granular media can be fluidized in either
microgravity or hypogravity.

• Radial distribution is comparable to a fixed bed,
  while the axial gas mixing is reduced
  considerably compared to a non-magnetized
  fluidized bed.

56
Electrostatics in Multi-phase Systems

• Dielectric constants of materials
• Glass beads (3.1), Air (1), Norpar (2.5, m
• 1.3 mPas), Paratherm (2.17, m 30 mPas),
• Water (88) (www.assiinstr.com/dc1.html)
• 150 mm glass beads in different fluids
• After 30 sec. Agitation (wall material glass)
• Multi-layer formation in glass beads-Air
• Mono-layer formation in glass beads-Norpar system
• No static generation in Paratherm (low energy
  impact between
• particles due to high m) and Water (fast
  dissipation of static)

Close-up of the Liquid-Solid Magnetically
Assisted Fluidized Bed showing particle chain
formation at high magnetic field
(Pinto-Espinoza, 2003)
Particle chain formation
Liquid
57
Acoustic Three-Phase Fluidized Bed
node
antinode
Pressure standing wave
Computational results of acoustic standing wave
effects on bubble rise velocity 16 kHz, ?9.4cm
Schematic diagram of acoustic gas-liquid-solid
fluidized bed
58
Gas-liquid mass transfer in a gas-liquid-solid
fluidized bed (Oxygen desorption method) UN2
0.5 cm/s, UH2O 0.5 cm/s, D 10 cm 1.74 mm
Activated Carbon, 5 by weight 16 kHz, 200W
Acoustic, ?9.4 cm
Acoustic standing wave effects on gas bubble and
particles 16 kHz, 200W Acoustic, ?9.4cm 1.74 mm
Activated Carbon
59
Concluding Remarks

• Industrial applications of three-phase
  fluidization reactor systems focus mostly on
  small or slurry particles in which reactor
  scale-up posts challenges under high gas flow
  conditions.
• Understanding bubble wake dynamics and
  bubble-bubble interactions is key to fundamental
  characterization of transport properties of the
  system and to ultimate success in the employment
  of computational fluid dynamics method.

60

• Issues on reactor operation
• Weeping in distributor and distributor design

recirculating liquid
entrained liquid plume by gas
gas layer
gas sparger
Liquid layer
Three-phase fluidized bed
Slurry bubble column
61
SINGLE BUBBLE FORMATION

• Initial Bubble Size Pressure Effect

Bubble columns Slurry bubble columns
62
(No Transcript)
63
(No Transcript)
64
(No Transcript)
65
3-D bubble plume velocity fluctuations and bubble
flux in G-L-S fluidized bed
66
Electrostatics in Multi-phase Systems

• Dielectric constants of materials
• Glass beads (3.1), Air (1), Norpar (2.5, m 1.3
  mPas),
• Paratherm (2.17, m 30 mPas), Water (88)
• (www.assiinstr.com/dc1.html)
• 150 mm glass beads in different fluids After 30
  sec. agitation
• Multi-layer formation in glass beads-Air system
• Mono-layer formation in
• glass beads-Norpar system

• No static generation in Paratherm (low energy
  impact between particles due to high viscosity)
  and Water (fast dissipation of static)

Wall material glass
67
Electrostatics in Multi-phase Systems
Particle chain formation

• Close-up of the Liquid-Solid Magnetically
  Assisted Fluidized Bed showing particle chain
  formation at high magnetic field (Pinto-Espinoza,
  2003)

Liquid