Is there any data on flowrate with pressure vs width of filter?

Hash and Stuff Extraction
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Hey!

So I’m just investing into a filter stack. And it seems like a good rule of thumb in any pressure vessel, is there’s a correlation between width and pressure capabilities in a tube style filter. Your clamps and gaskets need to get upgraded significantly, the wider you go.

I’m curious if there’s a “sweet spot” with costing, and filtering speeds, while correlating pressure and width.

Are you better off at 60psi at 3" rather than 20psi at 6"?

Does anyone have some experience? I’ve read the threads about never going over 15-20psi on 6"+

Has anyone found that sweet spot with average off the shelf stuff?

Should I invest in 4+" instead of 3"?

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bags or magic dirt?

I suggest we use your itty bitty fuge instead :wink:

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Dirt, and charcoal.

I’m coming over to the t5 charcoal camp from what @Akoyeh has been touting.

I definitely think the fuge is a potentially good solution though… Just keep adding charcoal until the color is right. Seems almost foolproof.

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I’m also got a lenticular filter housing and just found a 130psi gear pump for $100.

So… My shits gonna get the charcoal… We just need to figure out which charcoaling is the best charcoaling

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All I know for sure, is this thing at 30psi sucks nuts (not in any kind of good way)

I have like 200sqft of 1 Micron bag here, and a wife that sews

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yeah no. that is not the way to play that trick.

might be damn useful for some other things I’ve got to get sorted :shushing_face:

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I’ll tell ya 60 psi in a 4” ain’t much better. I think surface area is a better measure for how fast you can filter rather than how hard you can push.

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that is certainly my take on filtration.

although I’ve resorted to sucking and blowing on the same filter to get the job done. along with back-flushing with n2 so as to rebuild the bed.

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I’ve also seen some serious deformation of steel at less than 75psi. Make sure when pushing the limits of pressure on your system that there are emergency PRVs and maybe a blast shield. Haha. At least keep a @cyclopath in the corner to call for help or peel you off the wall with a mop handle…

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Seems like giving it the old spinaroo is way more surface area

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If you can keep the magic dirt in the right place and prevent tincture from going anywhere but through the media.

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I’m reminded of aquarium filters. The cheap carbon-filled versions, but the concept.

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The fluids calcs are fairly simple, but the overly simplified gist of it is that your flowrate through your pipe/filter is most heavily influenced by the pressure differential you can achieve (i.e. pump discharge = 30psi, outlet at 0psi, means a total differential of 30psi). The kicker is that every pipe and fitting and filter in the line causes it’s own resistance and corresponding pressure losses so your real delta P might be much less than 30psi.

The trade-off here is that smaller diameter piping can generally withstand greater pressure, but also offers an exponentially greater resistance to flow, requiring a greater pressure in the first place. The opposite is true of larger diameter piping.

It’s difficult to give exact numbers because most of the fluids characteristics that exist are all experimentally derived and noone has done any experiments on the fluid properties of crude cannabis resin diluted in Ethanol. If you’re diluting at the standard 10:1 or so, you could probably get by just assuming pure Ethanol for the fluids properties.

The other big question specifically related to filtering is that the filtered material creates it’s own resistance to flow as it builds up a cake on the filter.

This is all fresh in my mind because my current pet project is developing a pressurized filter column for winterization so that I can stop spending half my day dumping buckets into vacuum filter funnels…:crazy_face:

Edit: to directly answer your original question, the cross sectional area of flow exponentially increases as radius increases meaning your flow resistance also exponentially decreases. Increased diameter pipe will exponentially increase your flowrate as long as everything else stays the same. The trick is keeping everything else the same in a bigger housing (not to mention bigger fittings get exponentially more expensive too).

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I destroyed a sintered disk at only 24psi. $300 piece of steel warped like contact lenses

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To be honest… my absolute favorite filtration was when I had a stack of panda liners filled to the brim with steel wool, lid off and slowly poured in methanol… it was really scary though.

Someone needs to make a panda clone that’s all SS and explosion resistant, with a locking lid that has a triclamp fitting on top.

I now use a keg that’s been fitted with a vacuum takeoff, mouth fit to a hemispherical reducer, 8” sintered disk, with a 24” spool on top

Build filter cake, top with wet alumina, and a mountain of stainless steel wool.

Starts to slow after about 7gal but with methanol it’s not a huge issue

Gwhat if there was some sort of device that could be used to spray a mist of slurry onto a spinning micron filter and allow one to build up a cake on the inside of a filter bag evenly as the fuge spins, then you fill it with SS wool to diffuse the liquid stream via shower head into the scrubbies?

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These tables show high pressure bolted clamps ratings vs the hinge clamps- both look heckin higher than what you were told? Or maybe I’m confused

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Usually those pressure rating tables are not based on any actual destructive pressure testing. I don’t remember the exact terminology but most of the non coded SS vessels and fittings have standardized pressure ratings because of some hand-waving saying “we welded this using good fabrication standards that are already tested so we don’t have to test”. This is how you can have the exact same SS vessel (normally 150psi rated) in 300psi propane service, because someone paid to do a pressure test.

Also, just because the table says the hinge won’t explode or shear off at 1500psi doesn’t mean the seals or the main body can handle 1500psi. you’ve already discovered this firsthand with your sintered disk…

The system is only as strong as the weakest link.

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