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CIP System Components and Configurations 99
The small heavy lined circuit in Figure 2illustrates the rinse to drain flow
path. All rinsing involve supply of water of the required quality to the break tank,
delivery to and return from the connected circuit, and discharge to drain. If gravity
return is applied, the static head must be sufficient to allow the CIP pump to operate
at less than 8to10in. vacuum during recirculation. If areturn pump is utilized, it
should be sized and controlled to stuff the CIP pump at 1to3psig (7–20 kPa).
The wash recycle will begin with a system fill step with the drain and
return valves closed, using the meter to control the delivery of sufficient water to
fill the CIPS and CIPR piping and create aminimal puddle of 3to5gal (12–20 L)
in the vessel being cleaned. Aflat plate vortex breaker will be required to operate
at this desirable low level. Following the system fill, the TOV will close and the
return valve will open. The unique operation of this system when washing
tanks (or atank in combination with aline) eliminates the problem of “balancing”
flow produced by CIPS and return pumps, and also the problem of “airlocked”
pumps that frequently occurs in the application of multi-tank systems, as
an air bubble in the return pump will be drawn through by the supply pump,
and an air bubble in the supply pump will be pushed through by the return
pump. Recirculation at the set point flow and pressure isachieved with great
reliability. Following confirmation of recycle by flow and pressure sensors,
heating will be initiated and chemicals will be introduced. Cleaning cycle
timing will begin following confirmation of return flow temperature and
conductivity.
Chemical
loop
AB
FE
FCV
Steam
Chemical
loop
Water
tank
block
PS
COND
HXR
RTD T LS
Restrictor
COND
CIP
Supply pump
(VFD)
SG
AWFI
TOV
Tank
recycle
Return
RTD
Drain
Ret
probe
Samp
Chemical
loop
Res
probe
Wash recycle Rinse to drain
T
Water
tank
CIP supply
CIP return
CIP supply
AWFI
CIP return
FIGURE 3 The addition of one valve to the CIPR line will allow single-tank bypass or recycle
operation for cleaning piping circuits.