Buchi Nano B-90, Operation Manual

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6 Operation
71
B-90 Operation Manual, Version B
6.6 Optimizing parameters
The relevant parameters for the spray drying process depend on each other.
List of spray drying parameters
• drying gas flow rate
• relative inside pressure
• inlet temperature
• feed rate
The properties of the spray dried solution determines the maximum process temperature. The
maximum thermal load of the solid particles is caused by the spray head temperature or by the
maximum inlet drying gas temperature. To reduce the thermal load on the feed, the sample vessel
maybe cooled.
The achievable droplet sizes depend on the installed spray cap. Mean values for water applications
are shown in the following table.
Table 6-1: Spray nuts
Spray cap
(hole size)
Mean water
droplet size (D
4,3
)
Approx. water
throughput
Span
( )
D
90
- D
10
D
50
4.0 µm 8 µm 20 mL/h < 1.4
5.5 µm 15 µm 60 mL/h < 1.6
7.0 µm 21 µm 150 mL/h < 1.6
Application information
To give an overview of the parameter settings best suited for a specific process, special training
papers can be downloaded directly from our webpage (www.buchi.com). For special applications
please contact us.