BUCHI Nano Spray Dryer B-90 - Manual (Page 75)

6 Operation
75 B-90 Operation Manual, Version B
NOTE
Inert gas pressure above the values (see Inert Loop B-295 operation, step 5) will activate the safety
pressure relief valve, causing inert gas loss.
Aqueous solutions or mixtures of organic solutions and water may freeze in the heat exchanger of
the Inert Loop B-295. Therefore, when working with water or mixtures with organic solvents, the
cooling temperature must be set above +10 °C. The use of the adsorption unit is highly recom-
mended when working with water / organic solvent mixtures.
A leaking Aspirator can cause high O2 concentrations in ‘closed loop’. If the concentration is consid-
erably high, stop spray drying process and check Aspirator for leakages immediately.
6.9.2 Dehumidifier B-296 operation
The Dehumidifier B-296 can be used in ‘open loop’ or in ‘closed loop’ configuration in combination
with the Nano Spray Dryer B-90.
! Warning
Death or serious poisoning by contact or incorporation of condensed liquid.
• Dispose of condensate safely after use
• Wear safety gloves
System preconditions
All system items must be correctly installed according to the kind of set-up, see section 5 for more
information. Carry out a final installation check (see section 5.9) before every spray drying process!
Operate the Nano Spray Dryer B-90 Advanced in ‘closed loop’ as follows
1. Switch on the Nano Spray Dryer B-90 Advanced.
2. Only in ‘closed loop’ configuration, plug the dongle into the Nano Spray Dryer B-90 (see section
4.10; socket c).
3. Check the oxygen sensor with ambient air. The Ambient oxygen concentration should be around
21 %.
4. Select the inert gas mode (~4 % O
2
or ~1 % O
2
) in “submenu 1”. The instrument automatically
detects the connected dongle.
5. Turn on the inert gases N
2
and CO
2
. Set the CO
2
pressure to maximal 2 bar and the absolute N
2
pressure below 1.3 bar.
6. Switch on the Dehumidifier B-296.
7. Switch on the Aspirator.
8. Switch on the heater by pressing the “Heat” button and wait until the system has reached
stationary temperature conditions (typically after 5 to 10 min.).
9. Turn on the peristaltic pump to supply the spray head with a pure organic solvent test solution on
base of the target sample solution.
10. Press the “Spray” button, the system switches on the high voltage at the collecting electrode.
The inert gas flow starts working together with the spray head. As soon as the inert gas mixture
has reached optimal processing values, the spray LED starts blinking.