BUCHI Inert Loop B-295 - Manual (Page 23)

4 Description of function
23 B-290 Operation Manual, Version I
The nozzle cap has an inserted ruby stone with a precise opening and sharp edges to guaran tee a
precise and reproducible spray cone.
The smaller nozzle cap of 1.4 mm diameter leads to a lower consumption of spray gas, as the
concentric ring around the nozzle is smaller. This nozzle is recommended when nitrogen is used to
minimize operating costs. The larger nozzle cap opening of 1.5 mm is typically used when air serves
as spraying gas, as this design is more robust regarding concentric alignment to form a vertical and
uniform spray cone.
Optional nozzle sets with 1.4 mm or 2.0 mm nozzle tip diameter are available to increase the droplet
size and/or to spray more viscous samples or dispersions.
4 .3 Outlet filter
The outlet filter, consisting of a polyester textile, prevents environmental pollution and the possible
corrosion of the aspirator by very fine particles which cannot be separated in the cyclone. It can be
washed by hand or machine. All needed connections are included.
The second filter included is made of a PTFE membrane. By counter-pulsing the filter with pressurised
air, some of the collected particles can be reco vered resulting in a higher yield (see chapter 6.6.
The manometer indicates the system pressure in front of the filter. With a clean filter, the corresponding
pressure drop is marked.
4 .4 Inert Loop B-295
N
2
5
7
1
3 4
2
6
Mini Spray Dryer B-290
Advanced
Inert Loop B-295
a Feed
b Product
c Exhaust gas
d Solvent e Preheat exchanger
f Condensation
g Cooling unit
Fig. 4.3: Combined system of the Mini Spray Dryer B-290 and Inert Loop B-295
The Inert Loop B-295 is an accessory to enable the safe use of organic solvent in a closed loo.
The inert gas is loaded with solvent from the spray drying process. After precooling in a preheat
exchanger, the solvent is condensed in a refrigerator and collected in a closed bottle. The cleaned
gas stream is preheated in the preheat exchanger and flows back to the Mini Spray Dryer B-290
Advanced.