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Seiberling
provided, generally on the skid. Some designers provide a separate supply
reservoir for each flush, wash, and rinse solution required by the CIP program.
Presented in Figure 1isacomposite design of all the components required to
configure aone-tank or two-tank skid to operate in three different manners. The
circled numbers 1–20 arereferenced in parentheses in the following paragraphs that
explain each component’s function.
Major Components
ACIP recirc tank, sometimes used also as the only water tank, is apart of all CIP
skids (1).The combination of aconical (or dish) bottom tank and outlet leg provides
adequate net positive suction head (NPSH) for the CIP pump with aminimal
volume of water in the tank. Atank outlet valve (TOV) (2) controls supply to the CIP
pump (3). Acasing drain on this pump is at the lowest point on the skid and will
fully drain the complete skid at the end of the program. Ashell and tube heat
exchanger (4) is shown vertically mounted for space considerations and drainability
is provided by installation of atangentially drilled restrictor between the inlet and
outlet tees. Heat exchangers may also be mounted horizontally,apreferred practice
for large units. Steam supply and temperature controlisdiscussed in Chapter 7. The
CIPS piping on the skid includes the conductivity sensor,pump discharge pressure
sensor,and CIPS temperature sensor,all near (5), and the flow continues to the flow
element (generally avortex meter, mass flow meter, orturbine meter) and aflow
control valve (6). The choice of athrottling-type valve or apump with avariable
frequency drive for flow rate control inturn based on the meter analog output is
described in Chapter 7. The two close coupled valves (7) are optional and will be
discussed as part of three differentconfiguration scenarios. The CIPS then continues
to the process and the circuits.
ACIPR manifold on the skid is the general location for areturn-flow probe
(discrete), return-temperature probe, and resistivity probe, all (8). Areturn flow
hold-back valve (HBV) (9) is optional. The means of establishing recirculation
through the tank or around the tank will be discussed as part of the
configuration scenarios.
Single- or Multi-Tank Variation
Asingle-tank skid would require the provision of the water supply to the CIP
recirc tank. Asingle ambient water for injection (AWFI) source is shown via valve
(14) to aspray device (12). Two waters of different quality, ortemperature, are
commonly used, and both are supplied through individual spray devices.
A multi-tank CIP skid may be fitted with one or more water tanks to
accommodate the different water qualities or temperatures. The hot water for
injection (HWFI) TANK (16) is shown as an American Society of Mechanical
Engineers (ASME) vessel equipped with a rupture disc and is supplied with
HWFI by valve (18) through aspray to flush the tank head and sidewalls, under
control of alevel probe. Avent filter is shown and atemperaturesensor and sample
valve are indicated (19). If this tank is intended to be SIP’d it would be insulated.
Chemical supply to the skid is shown by means of achemical loop that
originates at optional valve (20), with arestrictor adjacent downstream to control
flow through the loop (see Chapter 8). The return connection for this chemical loop
is optional and will vary with the operating scenario.