Been using a cls to do positive pressure filtration. Way better than vacuum stuff. Just get silicone gaskets and pipe that chit through any filter with n2. Way faster. I’m sure y’all know a better way, how are you winterizing?
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get buna-n or filter plates and paper , silicone leeches into etoh. that’s how i used to do it…except i used 20 psi off the postitive pressure side of my diaphragm pump. i used a dewaxing column with dry ice , was too scared to use a slurry at the time. it works really well how quick is your nitro filtration? mine used to take around 3-4 hours
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Get one of those 12" tri clamp filter plate es for the bottom of your winterization column 
Or a sock filter
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Positive pressure with a sock filter works great
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Diesel fuel pump and a water filter system
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Buna-n is less compatible with ethanol than silicone. ptfe would be a more compatible gasket material for ethanol.
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Yup if you can secure a top on your filter setup head pressure is where it’s at. Pushes it through so much faster.
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I was told the other way around for buna-n vs silicone. I forgot about ptfe thank you for mentioning that. But PTFE Gasket filters are obviously the “expensive ghetto” way of filtering. I could never find low enough micron filters made with PTFE so I went with BUNA-N. Stainless filter plates/sintered filters and low micron filtration papers are obviously the best for filtration and the most expensive option but are THE BEST for filtration whether it’s etoh or hydrocarbons.
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Do you have to take any safety precautions when using positive pressure for filtering ethanol to stop it from going bang? Can you use a normal air compressor?
An air compressor works just fine, but will add some h2o… add an inline cheapo descicant chamber
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Cool thanks. Does the temperature of the ethol effect how safe this method is?
My ghetto positive pressure Honeypot filter…
Any tips on how I can make it better ? Running from keg with dip tube pushing with compressed air… Thanks
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Thats a small filter plate, whats your plan here? Filling most of the cone with celite/silica?
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Yup… was planning on filling with celite and alumina… was going to use for filtering after extraction and after winterization… how can I improve it? Bigger plate alone? Thanks
Use a pressure relief valve on all containers that will be pressurized.
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Without the proper filter/desiccant, one can also end up with compressor oil their crude. My suggestion is to use nitrogen if possible. Not fond of most compressors for this application.
Another thing to consider adding is a quarter turn valve at the inlet and a PRV on the housing itself, as @MagisterChemist suggested. It’s almost inevitable that at some point, you will likely experience blinding or fouling of your filter. Having the ability to stop flow and relieve pressure to examine and possibly fix the filter will be more handy than one would expect.
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lol, that is for sure. Funny that we ran into that situation ourselves today. This is why I recommend a way oversized filter for any initial particulate filtration because it bottlenecks everything after it.
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Please don’t do that. Murphy’s law dictates that a valve will be accidentally closed when the relief valve is actually needed. The better option is to hook an air compressor QC to the outlet of the PRV (male side) and run a line somewhere practical to vent the blow off. This allows you to connect it while I’m use and disconnect to clean/store.
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I’m sorry I wasn’t more clear in my response, as Murphy’s Law is one I regularly consider when building out my systems. Redundancy is always the key, and my system is never isolated in such a way as to encourage implosion or explosion.
Whatever vessel is being used to push said tincture should have an appropriate PRV installed as should the receiving vessel (which in the case of ethanol filtration, the receiving vessel can be left open to atmosphere). Any part of a system under pressure that can continue building pressure (or deepening vacuum), even when isolated, should be connected to a PRV, and when using more volitile solvents than ethanol, venting those PRVs appropriately should always be of concern. This particular system I have built out hundreds, if not thousands, of times feels pretty intrinsically safe.
@MagisterChemist got to see what I described in-person yesterday. Did you feel there would be a concern with installing the quarter turn valve where I suggested? I’m genuinely curious now. @cyclopath, thoughts? Would @SidViscous’s solution be superior?
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Not nitpicking your system, I should have been more clear. Just wanted to point out that making it so you can valve off a relief device is bad practice without proper design considerations. Certainly it is common practice to use a 3-way so that relief valves can be replaced or serviced in continuous service systems. Just didn’t want random readers to not consider the concern.
I’m sure we are on the same page mate
Also, as a quick clarification, if you do the vent tether thing I suggested, make sure considerations for the hose whipping are made especially if the vessel pressure is high. Nobody wants to get hit upside the head with their vent hose
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