23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
1
Fluid Bed Pellet Coating Process:
An Exercise in
Process Engineering Fundamentals
Darrell Staggs, P.E.
Associate Engineering Consultant
Process Engineering Center
Coated Pellet Formulation
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
3
Understanding the Process Technology
The pellets are spray-coated with layer
after layer of other materials, including
API, while being blown around inside
the MP10, a large stainless-steel vessel
that works something like a
giant hot-air corn popper,
said Nic Chornet, team leader for
manufacturing at IndyDry.
MQ News
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
4
Fluidized Bed Pellet Coating
The Basics
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
5
Define the Process
Critical Process Parameters
•Suspension
T, Mill Speed, Product T during Coating
Everything Else
•
•
•
•
•
•
•
•
Solution / Suspension Preparation
Air Preparation and Delivery
Solution / Suspension Delivery
Droplet Formation
Pellet Transport and Coating
Film Formation and Drying
Pellet Classification
… 70+ Variables
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
6
The Mass Balance
Solids Applied
Water Evaporation
Coating Efficiency
Pellet Potency
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
7
Pellet Coating Layers
A Consistent Quality Product
Sugar Core
API
Subcoat
Enteric
Color
Analysis of Spheres SEM and Image Analysis Eric Olson
6/30/03
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
8
Pellet Coating
Integrated Unit Operations
Suspension
Makeup
Baghouse
Pump Skid
Filter Skid
Coater
CIP System
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
9
DEFINE the Process
Process Thermodynamics - Air Preparation and Drying
0%
=4
RH
0.0320
RH
RH
=8
0.0340
=6
0%
0%
Psychrometric Chart
0.0280
0.0260
Exhaust
40 C 48% RH
h = 90 kJ/kg ⎯⎯→
0.0240
0.0220
0.0200
h = 70 kJ/kg ⎯⎯→
0.0180
30 C
60% RH
0.0160
0.0140
De
8 hu
C m
de id
w if y
pt
Humidity Ratio (kg H2O per kg dry air)
0.0300
RH = 20%
Dr
yin
g
h = 50 kJ/kg⎯⎯→
0.0120
0.0100
0.0080h = 30 kJ/kg ⎯⎯→
Heat
Inlet
80 C
0.0060
0.0040
0.0020
0.0000
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
Dry Bulb Temperature (C)
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
10
100
Process ThermodynamicsIncreased Inlet Air T
0%
=4
Exhaust
40 C 60% RH
0.0300
0.0280
0.0260
h = 90 kJ/kg ⎯⎯→
0.0240
0.0220
Dr
yin
g
0.0200
h = 70 kJ/kg ⎯⎯→
0.0180
30 C
60% RH
0.0160
0.0140
De
8 hu
C m
de id
w if y
pt
Humidity Ratio (kg H2O per kg dry air)
RH
0.0320
RH
RH
=8
0.0340
=6
0%
0%
Psychrometric Chart
RH = 20%
h = 50 kJ/kg⎯⎯→
0.0120
0.0100
0.0080h = 30 kJ/kg ⎯⎯→
Heat
0.0060
Inlet
95 C
0.0040
0.0020
0.0000
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
Dry Bulb Temperature (C)
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
11
100
Process Thermodynamics- Favorable
Coating Conditions vs. System Capacity
0%
=4
RH
0.0320
RH
RH
0.0340
=6
0%
=8
0%
Psychrometric Chart
0.0300
Humidity Ratio (kg H2O per kg dry air)
0.0280
0.0260
h = 90 kJ/kg ⎯⎯→
0.0240
AHU + Coating
95 Inlet, 8 D.P.
0.0220
0.0200
h = 70 kJ/kg ⎯⎯→
0.0180
RH = 20%
0.0160
0.0140
h = 50 kJ/kg⎯⎯→
0.0120
0.0100
0.0080h = 30 kJ/kg ⎯⎯→
0.0060
0.0040
0.0020
0.0000
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
Dry Bulb Temperature (C)
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
12
100
Process Thermodynamics: Conclusions
Evaporative Capacity
AND
Relative Humidity Environment
Increase with increasing Inlet Temperature
BUT,
That does NOT fully define the coating environment.
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
13
Sustain the Process
Equipment Qualification
How to QUALIFY a Precision Coater™?
All Columns performing
equally
Air Flow Distribution
• Atomization Air Control
• Spray Rate Control
• Temperature Response
•
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
14
Temperature Mapping a Precision Coater™
100
95
Column Inlet T
vs. Inlet Air T
vs. Set Point
vs. Time
90
TC1
TC2
TC3
TC4
TC5
TC6
TC7
TC8
TC9
TC10
Setpoint
Inlet Temp
85
75
70
65
60
96
55
95.5
50
9:10:05
9:38:53
10:07:41
10:36:29
11:05:17
11:34:05
TC2
94.5
12:02:53
TC3
94
TC4
Time
Column Inlet T
Variability
TC1
95
Temp, C
Temp, C
80
TC5
93.5
TC6
93
TC7
92.5
TC8
92
TC9
TC10
91.5
Setpoint
91
TT5209B
90.5
90
13:14:53 13:17:46 13:20:38 13:23:31 13:26:24 13:29:17 13:32:10 13:35:02 13:37:55
Time
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
15
23-Sep-2010
D. W. Staggs
8RD04
8RD05
8RD30
8RF93
8RF94
8RF95
8RF96
8RF98
8RF99
8RH26
8RH28
8RF97
8RH29
8RH30
8RH31
8RJ82
8RL13
8RL14
8RL15
8RL53
8RL54
8RL55
CT506492
CT507303
DTS23810
DTS23818
CT507304
CT508801
7RA52
7RA53
7RA54
7RH05
7SG37
7RH06
7SG28
7SG29
7SG30
7SG31
7SG32
7SG33
7SG34
7SG35
7SG36
7SG38
8RD01
8RD02
Oversize Pellets, kg
Improve the Process - Secondary Loop
The Problem: Pellet Agglomeration
Coating=Active
Control Chart
Individual Measurement of Oversize Pellets, kg
160
150
140
130
120
110
100
90
80
70
60
50
UCL=56.54
40
30
20
10
Avg=16.82
0
Lot
ISPE - Pellet Coating Process
16
Duloxetine
Pellet Coating Process
Pellet AGGLOMERATION
Wet Pellets
Inadequate
Drying
Diffusion Limiting
Drying Curve
API
(compare to talc)
Air Flow
Air distribution
Bed vs. Column
Poor Spray
Large Droplets
High Relative
Humidity
Environment
High Spray
Rate
Low Exhaust
Temperature
Air flow maldistribution
Spray Nozzle
Atomization Air
Low Pressue
Slurry Properties
Delivery System
Water Leak
Solids
Concentration
variability
Condensation
Viscosity
Mis-Alignment
Nozzle Tip Wear
Data:
UofC Spray tests
Insert size
Free Moisture
Plate pluggage
HPMC?
control valve
clearance / shear
API solids prop's
API solids prop's
Outside Air Leak
Cold Surface
Low Flow
Pellet
Distribution
column loading
Aeration
Low Pellet
Circulation
Fouled nozzle
Low Energy
Input
Tank/ Agitator
design / operation
API solids prop's
Solids
"Flooded" Column
UC spray data
Air flow rate
Particle Size
Distribution
Inlet Temperature
Aspect Ratio
Low initial
temperature
Crystal Habit and
Morphology
DWS
1-Sep-2004
Agglomeration Mechanisms rev-3.vsd
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
17
Spray Nozzle Testing
Spray Using MP-10 Nozzle for API Solution
Studies On The Spray Pattern of Nozzles Used In Niro MP-10 And MP-1 Precision Coaters
November 12, 2004 J. Zhou Process Engineering Center
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
18
Improve the Process
Pellet Agglomeration
Fundamental
Process Changes:
Atomization
Air P
Coating=Active
Control Chart
• Initial Inlet airIndividual
T Measurement of Oversize Pellets, kg
• Initial Air Flow
•
160
150
140
130
120
Oversize Pellets, kg
110
100
90
80
70
60
UCL=56.54
50
40
30
20
Avg=16.82
10
8RD04
8RD05
8RD30
8RF93
8RF94
8RF95
8RF96
8RF98
8RF99
8RH26
8RH28
8RF97
8RH29
8RH30
8RH31
8RJ82
8RL13
8RL14
8RL15
8RL53
8RL54
8RL55
CT506492
CT507303
DTS23810
DTS23818
CT507304
CT508801
7RA52
7RA53
7RA54
7RH05
7SG37
7RH06
7SG28
7SG29
7SG30
7SG31
7SG32
7SG33
7SG34
7SG35
7SG36
7SG38
8RD01
8RD02
0
Lot
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
19
Process Engineering Fundamentals
“There is no result in nature without a cause;
understand the cause and you will have no need of the
experiment. “
“Therefore O students study mathematics and to not
build without foundations.”
“He who thinks little makes many mistakes.”
Leonardo Da Vinci
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
20
The Fluid Bed Pellet Coating Process
Questions?
23-Sep-2010
D. W. Staggs
ISPE - Pellet Coating Process
21