Hamp seeds

Hemp seeds use to have a huge fat content. For this, a grinding with Variable Speed Rotor Mill PULVERISETTE 14 and 0,75mm sieve ring (as desired) is even after embrittlement in liquid nitrogen impossible.

As expected, even with a low feeding speed, sample starts smearing directly and covers all openings of the used sieve ring. No further sample is able to pass the sieve ring after ~ 10g of sample has been fed.

With a low feed rate of embrittled sample, a grinding of higher amounts is possible. The used 1,0mm sieve ring use to be closed with sample only at the lower side there rotor is not having ribs and on the top side where the ribs.

A grinding of higher amounts should be possible.

Probably 1-2 cleaning steps could be necessary for a grinding of up to 1 kg of sample as desired. With bigger sieve openings (1,5mm), we are guessing that 1kg can be ground in one batch.

With the pin rotor and lid with pin inserts, oily and fatty samples use to get ground to differentsizes. The pins inside the lid and rotor use to crack the seeds to halfs, quarters and finer particles.

As we have seen after our trial with 50g of sample, the lids outline pins have been closed with sample.

It might be possible that new fed sample will push sticking sample to the outside, then up to 100g might get ground in one batch. If sample use to stick too strong, a cleaning step will be required at least after 70-80g of sample has been fed.

We are guessing that pieces which use to stick to the lids outer pin line use to be ground way finer as first pieces who got ground and could be found as half’s and quarters.

Sample can be ground for the first 3 minutes. Afterwards, so much fat or oil has been pressed out of the sample, that a sticking to the pestle occurred. Sample has been scraped off the mortar and guided to the pestle, between mortar and pestle, sticking sample has been pushed upwards, still sticking to the pestle and remained on the pestle.

After totally 5 minutes, grinding has been abborted; almost the complete sample use to stick to the pestle.

This effect can only be avoided by grinding in suspension.