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CIP Cleaning in place
• The circulation of non foaming cleaners without dismantling
the equipment.
• An automatic and systematic cleaning of the inner
surfaces of tanks, heat exchangers, pumps, valves
and pipes.
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CIP properties
• Strong and hot solutions can be used. The heat, the chemistry and the mechanics can be sustained long.
• The solutions can be reused.
• Can be automated and reproducibility is good.
• Investment in equipment is high.
• The mechanics are not always sufficient
JohnsonDiversey
JohnsonDiversey
Flow Rate vs. Flow Velocity
∏=
..3600
.4
2d
Qv
Where,v = flow velocity meters per secondQ = flow rate m3 per hourπ = pi (3.1415,…) dimensionlessd = inside pipe diameter meters
second 1secondper volume
diameter inside
JohnsonDiversey
Velocity vs flow
1.5 m/s velocity 2.0 m/s velocityPipe size ID mm
Litres / sec Litres / sec
DN 50 47 2.6 3.5
DN 80 77 6.9 9.3
DN 100 97 11.1 14.8
DN150 147 25.5 33.9
JohnsonDiversey
Vertical vessel flow requirements - sprayballs
� Vertical vessels
� For most vessels, the sprayball delivers a uniform
quantity of solution to the upper circumference of the
vessel
� Based on soil level, deliver a given quantity of solution
to a unit length of circumference - called liquid loading:
� Don’t forget about flow OUT of vessels
JohnsonDiversey
Sprayball Placement
Θ⋅+=2
-180tan D Height Dome Sprayball ofDepth
Where,θ = angle of coverage, degreesD = diameter of vessel, metersDome height meters
NOTE: This is valid for simplevessels without obstructions.Additional sprayballs may berequired.
Depth of Sprayball
Dome WeldSprayball
Dome Height
140º
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example
15’
100 gpm
6” dia.
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Sprayball pressure
� Sprayball pressure is critical
� Generally in the range (1.0) 1.5 - 2.5 (3.0) bar
� Too little pressure and the vessel walls are not reached
� Too much and the spray atomises reducing mechanical
action
� Larger sprayballs with larger hole diameters can operate
at higher pressures without atomising.
� All sprayballs have specified flow / pressure curves
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JohnsonDiversey
Vertical vessel flow requirements - sprayballs
� Flow as a function of diameter and soil
� QR = required flow rate liters per minute
� DT = vessel diameter meters
� p = pi (3.1415,…) dimensionless
� FS = soil factor liters/(meter-minute)
� FS = 27 for light soil conditions
� FS = 30 for medium soil conditions
� FS = 32 for heavy soil conditions
SFTDRQ ⋅⋅= π
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JohnsonDiversey
JohnsonDiversey
High pressure rotary sprayheads
� Add impingement to the mechanical action
� Generally consume a little less water
� Have specific times to wet surfaces and impinge on them dependent
on pressure and gearing
� Not very effective on larger vessels under 5 bar pressure
� Use similar data to specify as sprayballs
� Use manufacturers recommendations
� Toftejorg have a computer simulation
program called TRAX - use it
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CIP Optimizing
� CIP optimizing is the process of minimizing the cost inputs of CIP
cleaning
� water
� effluent
� energy
�chemical
�electrical
�heat� CO2
� production time
JohnsonDiversey
Optimizing drivers
� CIP system design
� clean circuits - no dead legs, no flow splits
� accurate and non competing instrumentation - conductivity
monitoring
� no leaks
� CIP program
� correct CIP program philosophy
� CIP preparation sequence - correct conductivity starting point
� tidy CIP fluids interface management - always in lines never in
tanks
� correct valve sequencing on monitor signals
� defined terminators each CIP step
JohnsonDiversey
CIP optimizing - circuit volume
� To predict CIP losses and costs we must know the CIP circuit volume.
� This has nothing to do with the size of the CIP tanks.
� It is the amount of liquid held up in the CIP headers and the vessel or line being
cleaned.
� To calculate the circuit volume for a line clean we need to know the diameters of
the lines and the length of each line size.
� To calculate the circuit volume of a vessel clean we need to know the line
information and the dimensions of the vessel being cleaned.
� If there is other processing plant in the CIP circuit, we need to know it’s volume
too.
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Vessel Hold-up Volume
� Assume a 2 millimeter film thickness
(0.002 m)
� Assume a completely wetted surface
� Determine internal surface area
� Dome
� Cylinder
� Cone
Dome
Cylinder
Cone
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Vessel Hold-up Volume
� Area of Dome:
� Area of Cylinder:
� Area of Coneh2
h1
D
2DomeArea rπ=
2CylinderArea hDπ=
( )2121
2
4ConeArea hDD +=π
Dr2
1:NOTE =
JohnsonDiversey
CIP optimizing - chemical loss management
� Liquid loss for an efficient vessel CIP system is about 10% of circuit volume.
� Line cleans can be run more efficiently than vessel cleans - as low as 5% loss.
� Effective loss management depends on:
� Effective Flow meter or conductivity interface detection.
� Managing liquid interfaces into pipes not vessels.
� When managing liquid changes in vessels the program must be stepped.
� New liquid to sprayball chasing old liquid into vessel.
� Over scavenge old liquid from vessel into return line.
� New liquid into vessel chasing old along return line to interface
detector.
� First step should be volumetric and set for each vessel.
JohnsonDiversey
CIP optimizing - chemical loss management
� measured as % of concentrate detergent lost compared to the concentrate
detergent in the CIP circuit volume
� concentrate detergent lost is calculated by CIP tank, volume and
concentration, before and after CIP
� concentrate detergent in circuit volume calculated as the volume of solution
held in the CIP circuit excluding the CIP tank at the starting concentration
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The CIP flow is best circulated bypassing the CIP tankswith theheating and chemical dosing in line
