Fastest way to filter after cryo ethanol extraction?

Currently doing bucket tek with -80C ethanol. I’ve been using 5 gal buckets but about to switch to doing the extraction in a 30 or 55 gal barrel. I use 5 gal 220 micron bags to hold the biomass, pull them out of ethanol and spin them in a panda. I have a 3 stage water filter set up which filters into rotovap with 50, 10, 1 micron filters. The housing is PP so the ethanol has to warm up before it can go thru the filter. Problem is when I let the solution warm up to -10C or higher the color goes from gold to green pretty quickly. So I’ve been using the 5 gal refinement filter from BVV to filter while still cold. It works ok, but is kinda slow.

What I want to do is this:

Biomass soak in ethanol in a barrel
Pull bags of biomass and spin in panda
Transfer spun out ethanol back to barrel and filter thru a stainless steel filter housing using negative pressure and 100L stainless solvent tank.

For the housing I’m thinking something like this:

With a 50 micron filter.

Does anyone do something like this? My concern is that the filter would need to be changed out in them middle of the run which seems problematic.

Any other cheap ways to filter the fine sediment you can recommend?


Put a 1micron liner in your panda.

Spin bags out, pass test of tincture from barrel through panda.


The liner doesn’t have to be a bag, but it will help getting the filtered biomass back out of your panda.

Caveat: in my experience, pandas can get pretty pissy when feed too much liquid at full speed.

So securing them is recommended. I’ve seen a variety of methods, most use ratchet straps, I tend to use discarded inner tubes :shushing_face:

If your panda has a half speed mode, I recommend you filter there, and turn it up at the end to dry your cake


I stacked multiple layers of micron felt material in the panda and did not need to sew it- just fcut to fit and unroll inside.

Easy as heck, filtered 1gal/1min


I found some 250 micron bags a while ago. You have any examples/links of a viable options?

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Way too big.

Get micron felt material from Duda diesel and cut to fit- it’s found on eBay and amazon as well


I uses a 25micron, in a 160 micron, slipped into the panda. Scoop, fill, hold, turn on, then off, tip. Repeat

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Yeah when I first got the panda, I thought it was stable so I walked away for a second only to come back to see it spilling ethanol all over the floor b/c it walked away from my collection pan. Lesson learned.

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how many spots should a “panda rack” have?

I’ve seen a number of implementations, but none that strike me as the solution. do we need a “strapping down a panda” thread?


This does the trick for me… acouple 2x4 and a hook.

Also 5 gallon paint strainers are 100 micron. Doesn’t quite get all the plant matter but most of it. I use nutmilk bags @ 40 microns to get the rest, but there small and harder to work with


A super simple and cheap filter bag is a 5 gallon all mesh bubble bag. I think I pay 5.00 or so. I have bags going on 3 yrs.


That looks brand new

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