# cip cleaning in place - predict cip losses and costs we must know the cip circuit volume. this has...

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• JohnsonDiversey

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

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• JohnsonDiversey

Flow Rate vs. Flow Velocity

=

..3600

.4

2d

Qv

Where,v = flow velocity meters per secondQ = flow rate m3 per hour = pi (3.1415,) dimensionlessd = inside pipe diameter meters

second 1secondper volume

diameter inside

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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

Dont forget about flow OUT of vessels

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Sprayball Placement

+=2

-180tan D Height Dome Sprayball ofDepth

Where, = 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

140

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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 =

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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

• JohnsonDiversey

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 its volume

too.

• JohnsonDiversey

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

• JohnsonDiversey

Vessel Hold-up Volume

Area of Dome:

Area of Cylinder:

Area of Coneh2

h1

D

2DomeArea r=

2CylinderArea hD=

( )212124ConeArea hDD +=

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.

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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

• JohnsonDiversey

The CIP flow is best circulated bypassing the CIP tanks with theheating and chemical dosing in line

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