73
New Brunswick Scientific
User’s Guide
C.
To protect hydrophobic filters from blockage, which would occur if condensation
were allowed to wet and block the filter surface;
D.
To protect susceptible vessel assembly components from steam damage.
The first objective is met by leaving at least one vessel port open, the second by
clamping shut flexible tubing attached to immersed penetrations, and the third by
wrapping filters with a protective cap of aluminum foil. Use protective caps on probes
and bearings to meet the fourth objective.
8.1
Initial Preparation for Autoclaving
To prepare the vessel for sterilization:
1.
Remove the motor from the top of the vessel and carefully put it aside.
2.
Lubricate the vinyl bearing housing cap with silicone grease to facilitate sliding the
cap securely onto the housing.
3.
Place the bearing housing cap on the top of the bearing housing.
4.
Disconnect the air and/or gas lines from the inlet filter on the sparger.
5.
Disconnect the water lines. Remove all PVC tubing.
6.
Clamp off the harvest tube, the sample tube and all other penetrations that are
immersed in the media.
7.
Remove the RTD from the thermowell.
8.
Disconnect all probes and sensors, and remove their cables.
9.
If you are using pH and DO probes, install each probe’s shorting cap (provided in
the probe kit).
10.
Before placing the vessel into the autoclave, loosen the glass sample bottle by ½
turn.
11.
Wrap all filters with aluminum foil to protect them from steam.
12.
Attach a piece of tubing, wrapped with some non-absorbent material (such as glass
wool or non-absorbent cotton) to each of the addition ports. Wrap foil around the
end of the tubing, shaped like a funnel, to allow the vessel to vent more easily
during autoclaving. Place a clamp on the tubing.
#
NOTE:
Be sure to leave one clamp open during autoclaving to equalize pressure.
If you have addition, foam trap or harvest bottles mounted at the base of the
vessel
, you can autoclave them with the vessel. Without detaching their tubing from
the headplate:
13.
Remove the bottle holder(s) and reinstall each on one of the headplate clamping
screws.
14.
Reinsert the bottle and turn the holder until the bottle and holder are positioned
over the headplate, rather than extended over the edge.
15.
Finger tighten the knurled nut.
16.
Clamp off the tubing, and, where appropriate, remove it from the pump.
