Post Cold EtOH Extraction Filtration

Ok so, I’m working through filtration possibilities post ethanol extraction. It seems like it would be advantageous to filter out particulate asap, like right after bulk solid removal (ie post centrifuge) inline, while transferring into the next batch of biomass as a way to minimize any undesirable plant compounds from being picked up. Obviously if it’s possible to maintain temps through the system, filtration could wait until a given batch of EtOH is transferred to a holding tank.

Is filtering between batches of biomass overkill? Would this be as simple as using a bank of sanitary screen/ filters inline while transferring/ recirculating into the next batch of biomass? After the EtOH has been saturated and particulate removed, is it necessary to pass the tincture through silica/ carbon/ or ?? inline while transferring to a holding tank? Also, is it better to push or pull through inline filter media?

Last puzzle, let say that we’ve lost control of our temps and picked up some chlorophyll, proteins, waxes, etc. Filtration then winterization?

I’ve used a standard 10" x 4" 30um filter in front of one of these 30" sanitary filters with a 0.5um element and it worked great. A 20" would work fine but they’re an odd size to get cartridges for and I wanted bigger than a 10". They’re about 1/3rd of the cost of a lenticular filter. I would prefer a centrifugal pump over the peristaltic I was using.


There is a lot of good info on the forums here if you dig around. Search for the degumming thread and ethanol winterization thread. There is alot of talk of filter medias. The housings are pretty straight forward as you seem to understand.

Post extraction, the less contact the solvent has with the biomass , the better. Filtration at this point only serves to prevent continued extraction of non-target compounds.
A properly designed extraction arrangement will have very little carry over of particulate in the solvent.
Batch filtering every batch is a massive PITA compared to eliminating the requirement, at least until the initial winterization filtration. Batch timing is also a factor to be considered. If the solvent has to sit around for a while before winterization, I would be inclined to filter (20u) before storage.