5.2.2
Recirculate Cleaning Solution
Figure 28
System Setup for Circulating Cleaning Solution
Return the retentate line to the feed tank.
1. Open the retentate valve and close the permeate valve completely. Adjust the
pump speed to give a retentate flow rate in the range of 1 to 1.5 times the
recommended process CFF rate in Table 3.
Caution: Do not exceed a feed pressure of 2.8 barg (40 psig).
2. Run 45 to 60 minutes for cleaning.
If the cleaning solution looks dirty after only a few minutes, stop cleaning and drain
the cleaning solution. Follow steps 5.1.1 and 5.1.2 to flush with water through the
retentate then the permeate. Add fresh cleaning solution to the feed tank and follow
the steps in Section 5.2.1.
5.3
Flush Cleaning Agent from Cassettes and Assembly
Flush the cassette and hardware assembly with either:
1. WFI at 25 to 45 °C, or
2. 0.2 µm filtered DI water at 25 to 45 °C
Volume Required:
40 L/m
2
(4 L/ft
2
) minimum
To establish required flushing volumes for a specific application, test the pH and/or conductivity
of water from the retentate to determine when acceptable conditions have been reached. If the
product will be in the permeate, test the pH and conductivity of the permeate.
www.pall.com/biopharm
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Retentate
Permeate
Feed
Tank
Feed
Pump
Rp
Pp
Fp
