Our extraction system and SOP has been designed around hemp flower but as far from last seasons harvest as we are and not yet to harvest for this grow season, the amount of flower thats available to extract seems to be dwindling and I don’t want to give up on working, and hopefully making some more $$$ until people start pulling plants down.
That said, there seems to be pelletized biomass available for the extractor who can run it at a descent efficiency, in some pretty descent quantities, but from running a few test batches and reading on this forum - specifically, this thread starting here about post 12:
I suspect this biomass was over-compacted in the pelletizing process, and from a few small test batches we let steep in alcohol, the pellets don’t come apart very easily even after steeping in 190 proof at room temps for 12+ hours. I’ll note here that per our SOP we’re extracting frozen biomass with cold solvent and if 12+ hours at room temp didn’t completely turn the pellets into mush, 12 hours at cryo temps probably won’t do it either. To say nothing of how badly that would kill the lbs/hr or lbs/day I’m able to process.
So we tried sending some through our hammer mill to size reduce and expose more surface area, with some trial and error getting compacted material cut down to no more than ~6MM max length but after sending a couple samples of the spent material at varying exposure/agitation times out for lab testing it still seems like we’re leaving a larger amount of cannabinoids in the spent biomass than I’d like, and not hitting the extraction efficiencies we would normally see with flower either by the delta in TAC between pre- and post-extraction material from a lab we use and trust, or by mass transfer on the amount of decarbed crude we have coming out after the tea has made it through the solvent recovery and decarb steps of our process.
I suspect that the finer we can shred the pellets, the better our extraction efficiency will be, with the caveat that we are unable to process dust and hammer milling, even with a drastically slowed down speed seems to be putting out a mixture of smaller pellets and very fine dust, even using extraction bags a considerable amount of dust seems to make it into the solvent which then clogs filters…needless to say I want to avoid that.
I think getting it cut down to approximately rice grain size would give me an acceptable compromise between maximizing extraction efficiency and maximizing surface area without creating something so small I can’t process.
I guess what it all boils down to, is there a way to do this without just hammer milling everything completely down to dust and then repelletizing to my desired size? I don’t know much about pellet mills, to be honest most of my mill interest has been with size reduction not compaction up until this point ¯_(ツ)_/¯
If that is indeed my only option, should I be worried about the repeated compaction of this biomass doing something to kill my extraction yields, even if more surface area is exposed?