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Commissioning and Qualification 333
acircuit. The skid sequence typically has little variation from circuit to circuit (other
than set points and time). There may be some variation between CIP cycles;
however, the circulated wash steps are very similar to each other (as are the
once-through rinses).
Design Basis
The NDS and ABS design and determination of some of the critical operating
parameter values require the engineering and commissioning function to be
somewhat iterative. The NDS and ABS and associated times are typically
determined using adesign basis from rules of thumb (or designer experience)
and assumed flow rates.
Flow rates are initially estimated during the design phase. Flow rates for
cleaning via spray balls (and the spray ball design) are usually initially determined
based on the tank geometry. Minimum flow rate requirements for pipe filling and
cleaning can be calculated by engineering during design based on achieving
appropriate velocity (generally aminimum of 5ft/sec). Sequence time for line
cleaning is typically based on volume turnovers.
Sequence times for flow through spray balls are based on the number of
circuit volume turnovers as well as a minimum tank contact time. The total
number of NDS sequence iterations planned per cycle is based on the anticipated
needed contact time for the alkaline and acid cycles and on the anticipated
number of volume turnovers needed for the rinses. Adjustments are made as
data is acquired via functional testing (such as actual process transfer line flow
rates).
It is important to understand and document the basis for design so that
adjustments made during functional testing are within the capabilities of the
design. Flow rates and times affect virtually all aspects of the CIP design. Affected
areas include:
1. CIP tank sizing
2. Feed water flow requirements
3. CIP tank vent sizing
4. CIP circuit supply and return pump sizing
5. Circuit supply and return piping sizes
6. Heat exchanger sizing and associated utility needs
IQ AND FACTORY COMMISSIONING ACTIVITIES
Equipment is purchased and systems are fabricated and installed from the design
documents. The functional testing portion of commissioning is typically performed
on site after acompleted and verified installation. Functional testing does not
usually proceed until IQ activities have been completed for the CIP skid, supply
and return piping, and all of the process equipment system components used for (or
immediately adjacent to) the CIP circuits. Prior to starting the functional testing on
site it is prudent to ensure that all components associated with the CIP circuit
operations are per specification and are installed and working properly to
avoid rework.