1. Fouling & Cleaning Science: Direct Detection
of Biofilms and CIP-Related Problems in
Liquid Process Systems
Mark Fornalik
Industrial Biofouling Science, LLC
www.industrialbiofouling.com
2. Introduction:
Process Cleaning Science
There is a science around determining if your industrial process is truly clean,
and the tools for this determination include microscopy as well as FTIR. Both
are complimentary to the traditional microbiology methods.
This talk introduces fouling cell technology and how to understand the
sequence, chemistry and kinetics of fouling events on the interior surfaces of
pipes, tanks and liquid-handling processes.
2
3. Process Contamination:
Impact to The Bottom Line
• Poor product quality
• Random quality incidents
• Time spent sorting good product from bad
• Wasted materials (raw and finished)
• Sub-optimized process cleaning = process
downtime
• Erosion of customer base
3
4. Cost of Process Contamination
• In a Fortune 500 chemicals company, the fouling
cell approach:
– Found and eliminated the root causes for $20M in
product waste (note: most of this was biofilm related)
– Identified manufacturing sites with best cleaning
practices
– Reduced the cost of commercialization, by identifying
cleaning problems – and proper cleaning procedures
- in the product development cycle
– Enabled more robust process health
4
5. Transfer Line Contamination
Manufacturing Problems:
• Cross contamination between
product types
• Physical waste – spots,
streaks, particles, filter
plugging, viscosity changes
• Chemical waste – chemical
contamination of final product
• Increased brand change time
• Loss of product flow
• Increased production runs to
allow for waste
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6. Insoluble Wall Fouling
• Fouling: The unwanted formation of insoluble
residues on engineering materials in contact with
flowing solutions
• Fouling is what is left on wall surface after even a
proper water flush clean
• Chemical cleaning must be designed to address
water-insoluble wall fouling
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7. Insoluble Wall Fouling Types*
• Organic
• Inorganic
• Biological (bacteria, fungi, algae - BIOFILMS)
• Particulate (corrosion)
• Crystallization/Scale (boilers, heat exchangers)
• Combination (any two or more of the above)
* T.R. Bott, Fouling of Heat Exchangers, Elsevier (1995)
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8. Fouling Rate
steady state
fouling mass
physical
problems
chemical
problems secondary fouling
induction period
time
The goal of cleaning is to return the system to the induction period
level of fouling
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9. Fouling Cell Technology: Direct
Detection of Biofilms & CIP Efficacy
Fouling Cell Technology:
• Analyze fouling film while in place on substrate
• FTIR for non-destructive chemical characterization (organics)
• Epifluorescence microscopy determines if organics are biofilm
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10. Process Cleaning: A Structured
Approach
Biofilm Control
Chemical Clean Optimization
Water Flush Optimization
System Design
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11. Water Flush Cleaning
Water Flush Cleaning: A Two-Step Process
1. Product displacement – governed by hydrodynamics
2. Wall cleaning – governed by kinetics
1000
100
Old process water
flush end point
Percent of Dye in the Flush Solution
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1
Water flush M a g e n ta
Y e llo w
C yan
0 .1
“plateau “
0 .0 1
0 .0 0 1
0 .0 0 0 1
0 5 10 15 20 25 30 35
T im e ( m in u te s )
Insufficient water flush leaves product behind in pipe;
optimized water flush reaches “plateau” more quickly for
faster cleaning times 11
12. Powerflush (Two-Phase Flow)
Cleaning
Efficient flow ratio Water-rich flow ratio
Cleaning efficiency varies as a function of the ratio of air flow to
water flow
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13. Direct Measure of Powerflush
0.0080
Cleaning Efficiency
0.0075
0.0070
0.0065
0.0060
Before powerflush
0.0055
0.0050
0.0045
Absorbance
0.0040
After powerflush
0.0035
0.0030
0.0025
0.0020
0.0015
0.0010
0.0005
0.0000
-0.0005
-0.0010
3500 3000 2500 2000 1500 1000
Wavenumbers (cm-1)
Peak height data correlate to effectiveness of cleaning: the smaller
the peak, the more effective the cleaning
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18. Case Study: Comparing Cleaning
in Two Winery Product Lines
Fermentation cellar line
Cellar & bottling lines
cleaned daily with hot water
& iodophor before & after
each use Bottling line
Fouling cells
Filler line cleaned daily with
140F water, caustic/bleach,
peracetic acid, 190F water
Filler lines
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19. Winery Line A 10 Weeks
Fermentation
cellar line
Bottling line
Filler line 19
20. Winery Line B 10 Weeks
Fermentation
cellar line
Bottling line
Filler line 20
21. Winery Line A 10 Weeks Cellar A
cellar
carbohydrate
protein
2000 1000
bottling
surge
2000 1000 tank
filler
2000 1000
bottling A
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22. Winery Line B 10 Weeks
Cellar B
cellar
protein
2000 1000
bottling
surge
2000 1000
tank
filler
2000 1000
22
bottling B
23. Winery FTIR Peak Height
Comparison
Line A 82 Line/Line 4
Line B Cribari Line/Line 5
0.5 0.5
0.45 0.45
0.4 0.4
0.35 0.35
0.3 0.3
peak height
peak height
amide amide
0.25 0.25
carbo carbo
0.2 0.2
0.15 0.15
0.1 0.1
0.05 0.05
0 0
cellar bottling filler 1st cellar bottling filler A side filler B side
fouling cell location fouling cell location
Conclusions:
• Fillers from both lines were clean
• Both lines A and B exhibit biofilms in cellar and bottling lines
• Line A has thicker fouling layer
• Line A exopolymer is carbohydrate & protein; Line B exopolymer is protein
• Both biofilms resist daily chemical cleaning: hot water, caustic, peracetic acid, iodophore
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24. Case Study: Mapping Process
Cleaning in Bioproducts Plant
Fermentation
reactor
Centrifuge
Fouling cells
Process
filters
Recovery 24
25. Fermentation Fouling Cells
2-day exposure
before CIP
2-day exposure after
CIP
CIP: 5%
NaOH,
65°C, 30 4-week exposure
min daily after CIP
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26. Recovery Fouling Cells
2-day exposure
before CIP
2-day exposure after
CIP
CIP: 5%
NaOH,
65°C, 30 4-week exposure
min daily after CIP
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28. Conclusions
• Microscopy provides a valuable tool in industrial biofilm detection
and characterization
• Fouling cells provide an ideal way to acquire biofilms in full-scale
manufacturing processes
• Fouling cell technology is complimentary to existing microbiology
methods for biofilm analysis, enabling analysis of exopolymer and
biofilm morphology while still in place on the fouled surface
• FTIR analysis targets exopolymer and residual chemicals fouling
from product
• This approach can be used to “map” the cleaning effectiveness
within a process or compare cleanliness over different production
lines or sites, and determine whether product fouling or biofilms are
the root cause of process and product contamination issues
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29. Food Gelatin
Winery dye
Brewery
AgNO3
Bioproducts
Industrial salt system
Food dye
Ultrapure water 29
30. With Thanks to Kodak’s
Former Systems Cleaning
Group
M. Giang, M. Grannas,
D. Gruszczynski, J. Hunt,
D. Irwin, Y. Lerat, C. Puccini,
R. Schmanke, J. Steegstra, M. Wallace,
M. Wilcox, G. Wilson,
K. Brockler, J. Fornalik
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