Bag Filters for Ethanol Extraction

Does anyone have a lot of experience using bag filters post centrifuge? We are running -40c in centrifuge and solvent tank so hoping lipids won’t pull at that temp. Just trying to get majority of particles out before the 12" Lenticular AC filter. We have two #4 bag filter housings, I was thinking 10um and 1um?

I like to start at 25um and then stage down to 10um. I have had good luck. We also utilize pre injection coils to make sure we are staying -40c. If you think you lose a few degrees wouldnt hurt to put like a 5um filter at the end. You may run into it filitering slowly at the 1um. We also run massive amounts so we swap our filters out alot. 10um to 1um is a really good start to see if it works for your system. You are on the right track!.

I found lining the fuge with 1um felt made secondary filtration essentially superfluous…depends on your scale how applicable that is.

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Hmm that’s interesting…
Lining the outside of the inner basket or the inner of the surrounding drum? Are you talking about a bag? How would you attach this lining. TBH I love the idea of secondary filtration being superfluous.

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A lining on the inside of the drum. If u cut the right size and stitch it together, it should hold in place with centrifugal force. Once u run it a couple of times, it will almost glue to your drum. Only need to replace it when flow starts to slow down.

I setup a stacked system, so 50 micon felt closest to the bio and ended up with a 1 micron felt closest to the drum. There was 50,25,10,5 and 1 in there. Alittle overkill but i ran it for about half a year b4 having to replace it. Just took the 50 and 25 micron out periodically to rinse it (inside out).

After setting up the “prefilter” in the centrifuge, i think we only replaced our secondary filter skid once or twice per year.

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You still have stuff that misses the bag, and every now and then bags let go.