Yearbook 2013/2014 - ehedg

22 The importance of hygienic design: A process facility case study and checklist
2. Piping and instrumentation diagram (P&ID). This
involves one significant hygienic design principle:
d. Hygienic design principle 2:
Cleanability. During the definition of the P&ID for the
processing line, the following aspects should be considered
and included:
• Identify all of the different equipment that are part of
the process.
• Establish cleaning methods (i.e., CIP, manual, etc.)
and cleaning regimes.
• Evaluate restrictions inw the process and determine
alternative solutions to ensure that effective cleaning is
achieved.
In the cream cheese facility during the P&ID definition phase,
it was determined that for the CIP cleaning of the scraped
surface heat exchangers (SSHE), a reinforcement was
needed to ensure effective cleaning of the system (Figure
7). The red arrows represent the product flow and the pink
ones CIP reinforcement.
During the CIP cleaning additionally to the main route (red
arrows) there is a flip that makes a closed loop with the
SSHE, supported by a centrifugal pump.
Figure 7. CIP cleaning route for the scraped surface heat exchangers (SSHE).
3. Specifications for different suppliers. Once the P&ID is
completed, the next step is to define the detailed function of
the line (FDS), as well as the specifications for the quality of
the materials to be used. Once all this information is compiled
the specifications can be sent to the different suppliers in
order to get an estimated quotation for the installation.
Some hygienic design principles that are important to be
considered when defining the specifications are:
e. Hygienic design principle 2:
Cleanability.
• Identify the method of cleaning (e.g., CIP, clean-out-ofplace
[COP], foam, manual cleaning).
• Assess the capability of the equipment to handle
frequent CIP temperature exposure.
• Determine whether all of the equipment components,
such as valves, are designed to be cleaned in place.
• Ensure that the process connections of all the
measurement devices are hygienically designed.
• Decide how many process connections are needed.
f. Hygienic design principle 3:
Compatible materials. All materials that may come into
contact with food should not be able to make the food unfit
for consumption (e.g. toxic). As such, all materials used in
the composition of food manufacturing equipment should be:
• highly resistant to corrosion;
• nonporous with smooth surfaces;
• highly resistant to thermal variations;