6.6 Grinding with external cooling
For certain source materials, using coolants before milling can be benefi-
cial for comminution. For instance, soft organic materials or special plas-
tics can be made brittle by briefly immersing them in liquid nitrogen or
storing them in a freezer before grinding. Protect the source material
against condensation – e.g. a plastic bag could keep the source material
dry during cooling until grinding.
For highly temperature-sensitive source material, we recommend
cooling the source material with liquid nitrogen before milling and then
feeding the material into the funnel in very small quantities, e.g. with a
spoon spatula.
CAUTION!
Wear safety goggles and suitable safety gloves when using
liquid nitrogen!
When milling larger amounts (> 20 g) with external cooling,
always use the conversion kit.
Dry ice (solid carbon dioxide) can also be used for cooling. Keep in mind
that the surface of dry ice often contains frozen condensate, which can
potentially clog or contaminate the sieve ring.
6.6.1 External cooling
It is possible to exchange the lower ventilation grate on the rear panel
against a cover plate (order no. 14.4214.00) with a connector for a
vacuum cleaner (order no. 43.9070.00). This will provide faster airflow,
thus cooling the system!
Using the device
- 30 -