Oil palm Empty fruit bunch

For a comminution of such a sample, a cutting mill might be best. With the Cutting Mill PULVERISETTE 15, we received an output of 14 grams after 60 seconds of grinding. The openings of the sieve cassette use to remain free, but a lot of pre ground sample still remains in the grinding chamber.

Pre ground pieces of sample get compressed, mainly in front of the second fixed knife. We are guessing that about 70-80 g of sample might be fed to achieve an output of 50 grams as desired. Possibly, one cleaning step might be required to free fixed knives from residues.

It is possible feeding dry ice during grinding to improve the grinding result (when fat or moisture will be embrittled, sample will become less sticky to the knives).

As usual, fibrous materials can pass the sieve insert longitudinal, for this, even longer particles can be found after grinding.

A grinding with Universal Cutting Mill PULVERISETTE 19 is also possible. With fast openings for grinding chamber and a removing of cutting rotor and sieve insert without tools, cleaning and handling of the machine uses to be improved significantly.

For this, a Universal Cutting Mill PULVERISETTE 19 will be recommended for a daily grinding of samples.

With the harsh cutting sound of the coconut fibers, also a V-cutting rotor with fixed knives made of hardmetal tungsten carbide can be used for a longer durability.

With a little less of sample, we achieved and output of ~ 11,5 grams after 60 seconds until grinding sound got significantly reduced.

Sample did not stick that strong to the fixed knives, nor to the knives of the V-cutting rotor (possibly less oily seeds have been inside the second sample).

The openings of the sieve cassettes trapezoidal perforation are mainly free. A grinding of higher amounts might be possible too. Cleaning can be performed rapidly by vacuuming with a soft brush.

Optional, sample exhauster system with cyclone separator can be used to improve grinding speed.

About 7,7 grams of voluminous sample can be fed into a 250 ml grinding bowl. With the ruff surface of sintered corundum, organic fibers can be comminuted faster, compared to metal or smooth surfaced ceramic materials, but also higher abrasion on Al2O3 is expected to be found when longer grinding times will be prepared.

After 2 minutes of grinding, volume of sample collapsed. It shows that sample became compressed by the grinding balls, a typical comminution of fibrous materials has not been performed, probably rests of moisture, fat or oil content might be a reason for this.

To achieve a better fineness without a sticking of sample, probably a grinding in suspension might come into question.