Buchi Nano B-90, Operation Manual

Page: 53 / 104

5 Putting into operation
53
B-90 Operation Manual, Version B
5.6.2 ‘closed loop’ gas supply configuration
The Nano Spray Dryer B-90 Advanced has been designed to be used in ‘closed loop’. This mode is
universal and can be used to spray dry aqueous as well as solvent mixtures with air or inert gas under
safe conditions. To ensure the optimal drying gas performance in this operation mode the supplied
gas has to be dry and free of impurities.
a
b
c
The drying gas connections are located on the right
side of the instrument (see section 4.10 for details).
The connections are made via Polypress and Solaflex
tubing in combination with clamp fittings and via quick
coupling connection. The kind of connection depends
on the type socket and the transported gases. The
output gas is recycled by an Inert Loop B-295/Dehu-
midifier B-296. In ‘closed loop’ mode, the Aspirator
works as a recirculating pump to establish a constant
gas flow.
a
GAS OUT (Polypress with clamp fitting)
b
N
2
(quick coupling)
c
AIR (CO
2
) (quick coupling)
d
GAS IN (Polypress with clamp fitting)
5.6.3 Outlet filter installation/replacement
The Nano Spray Dryer B-90 is equipped with a safety outlet filter. This particle filter (order no. 051656)
has an efficiency of 99.9 % for particles < 1 µm.
The filter should be replaced when clogged. This is
indicated by a strong pressure drop (see also the error messages in chapter 8.1). Switch off the instru-
ment, remove the power cord before installation work and depressurize the system and all supply
tubes.
! Danger
Death or serious poisoning by gases or particles at O
2
– sensor or filter malfunction
• Exchange defective O
2
– sensor immediately
• Exchange O
2
– sensor regularly within the specified maintenance intervals
• Exchange clogged filters immediately
• Exchange filters regularly within the specified maintenance intervals
• Safely dispose filter immediately
Notice
Risk of instrument damage by internal overpressure.
• External supply pressure must meet the system specifications
• Exchange clogged filters immediately
• Safely dispose filter immediately