16
Start up of cassettes
5.6 Thermal Sterilization of Filter Cassettes
Check steamability with ”Specifications“[
Æ
During in-line steam sterilization the entire system, including stainless
steel piping and cassette filter holder, will attain > 121°C. Exercise due
caution when working around hot equipment.
Please note that steaming in place (SIP), due to high thermal and mechanical
stress, may impact the physical properties of a membrane in terms of flow
performance and rejection. Therefore multiple use is limited.
During in-line steam sterilization, hot steam exits from the feed inlet and the
permeate outlets. Keep a safe distance away from these outlets.
Before thermal sterilization, exchange the operating torque nuts to the torque
nuts for pressure compensation.
This special compensation tool is designed to maintain constant clamp force during
thermal sterilization. If the pressure compensation tool is not used, the torque will
increase beyond the maximum allowable value as temperature increases. This may
cause irreversible damage to the filter cassettes.
Thermal sterilization should only be performed on clean filter cassettes.
Contaminants will be irreversibly fixed by thermal sterilization.
The Stabilizing pressure inlet air should be sterile filtered.
Make sure that the steam you will be using is of pharmaceutical quality, free of
rust and other particles and does not contain any hydrazine.
Prior to thermal sterilization check the filter cassettes for residual traces of
chlorine or disulfide. To denature chlorine, flush with 1% sodium thiosulfate
solution followed by flushing with purified water.
Handling safety is increased if you attach thermal condensate run-off valves to
the retentate outlet and to the permeate outlets.
5.6.1 In-Line Steam Sterilization of Sartocon
®
Microfilter Cassettes
Stabilizing pressure inlet
Cassette
Permeate
Permeate
Feed Line
V
2
V
5
P
P
2
P
3
P
1
P
4
V
1
V
4
V
3
Steam
generator
Fig. 3: Diagram of the system for in-line steam sterilization of
Microfilter cassettes. V
1
–V
5
: valves; P
1
–P
4
: pressure gauge, P: pump