Best way to move cold EtOH from keg to keg?

Looking for the best way to move cold EtOH from keg to keg, any input/inspiration is very appreciated.

To be honest, Future’s Bucket tek upgrade is not 100% clear to me. I understand he uses pressure from a compressor to move the EtOH but don’t get the full setup/approach. Does it only work with raised barrels/kegs with drains in the bottom?

How cold?

If we’re talking down to -40/-50C a regular Ingersoll ARO or similar diaphragm pump powered by compressed air will get the job done. Below that you get into more specialized materials and higher costs in a diaphragm style pump. I’m leery to recommend compressed air to push the solvent around because the regulators tend to be way crappier quality on compressed air as well oxygen + flammable solvent is a recipe for a bomb. Nitrogen or CO2 are both far better options if you’re going to use a compressed gas to push. Should invest in a PRV if you’re going to use a compressed gas push, I see that lacking in a lot of labs that are posting keg pics on IG.

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Good question. Probably up to -72C as that seems to be what a dryice/ EtOH mix seems to be capable off. Not sure if I will be able to archive such a low temp in a regular, uninsulated keg though.

I hear u on the issue to use compressed air to push the solvent. Not the best option.

For now a pump would be my prefered option but I am here to learn.

Nitro only… Me and one the boss man here had this exact convo when I said I wanted reason just in case when I purchased my nitro for bho

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So u inject the Nitro in the headspace of the keg and have a lid with PRV and custom dip tube reaching all the way to the bottom of the keg to move the solvent?

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Thanks for posting that picture @Myrrdin

Curious, what would be the best diameter and style of tubing to pump from one keg to the next?

How would the perfect triclamp lid for a keg look like?

12" triclamp with 1/4" male NPT for 5psi PRV, port with dip tube (size/style?) and ‘feeding port’ (size/style?) I assume…

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Why would one use positive pressure as opposed to vacuum? To try and preserve terpenes?

No solvent losses to boiling

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But if the solvent is cold, it should not boil when u move it?

I actually thought the vacuum pump is ‘enhancing’ the flow rate, similar like when filtering with a Buchner funnel.

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Use a diaphragm pump on the suction side…

It’s like pushing with air bc it can positively displace the liquid. The temps won’t matter bc it won’t touch them and it won’t move as slow as a regular vacuum pump but it will in fact vacuum it out.

If it’s not already under blanket gas I’d imagine your oxidation risk is present and for what it is worth there is something called a bulldog which is used to create positive displacement in wine transfer or any barrels, spirits or ethanol related products. I have the more expensive version but they all work. Just different levels of fancy.

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http://www.bulldogmfg.com

Carlsen and assoc in Healdsburg, Ca.

Complete winemaker

All types of outfits sell them with VFDs and explosion proof Atech rating and continental hoses.

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You can still cold boil the solvent as well as create vapor lock in your circulation path under a vacuum.

Nitrogen tank with regulator, 10-30 PSI max depending on the MAWP of your solvent and collection tanks.

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You aren’t pulling much of a vacuum bc the other end is flowing, you are pulling a mild vacuum… and it’s terribly safe.

It’s used in the spirits industry all day, everyday.

Same business… 10000x bigger.

The one thing to watch for is opening up your tank to atmosphere or crush it like a soda can bc these pumps don’t take no for an answer.

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So just to confirm, use either the ‘bulldog’ or a diaphragm pump or in combination?

It works. Well.

AND you can inadvertently boil your solvent if there are restrictions, or a mismatch in pump cfm.

I have tended to use vac rather than N2, because a tank of N2 has the inconvenient habit of becoming empty when you most need it.

I’ve killed (and/or trained others to kill) a number of vac pumps. If your plan on -ve pressure, use a diaphragm pump. One rated for moving liquid at your process temp ideally.

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Most people are storing in kegs and beer glass carboys from what I can tell and the bull dogs are good for pushing.

The diaphragm punks are good for pulling. And depending on the wetted parts, they may work for cold temps but mag drive pumps are the best for cold

Explosion proof ones start around 1600$ and got up to the moon quickly.

Diaphragm pumps are very good at moving volume, so once you get past a small volume of say 60-100 gallons you’ll wanna step up to a diaphragm and pull vs using displaced air which may cost you a full tank of nitrogen.

There are tank calcs though for how many cubic feet the nitrogen tank will be to base your displacement volume.

Don’t dead head a diaphragm or it will blow the fitting off your receiving tank and crush the transfer tank. Oxidation for me, is less a concern in alcohol but to each their own.

If you are gonna worry about all that, then you’d wanna go a little further and blanket all your tanks first. Use a lighter to see if the tank is oxygen free. Unused and empty of course before your literal jerkies start talking shit bc your common sense brethren may cut themselves while running high with scissors blade exposed.

The lighter won’t light without oxygen so you know it’s displaced.

Often you can’t vacuum things like kegs and alcohol transfer items. It’s not like butane and pressure vessels… the cost is much lower for a reason.

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FWIW mag drive pumps are not self priming or positive displacement pumps.

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I am not so much worried about oxidation myself, only about moving the liquid.

So just to confirm, an explosion proof mag drive pump would be the best option to move the cold EToH from keg to keg?

Thats not totally true, you can use a plastic magnetic drive pump to move freezing cold ethanol as long as its not too cold (below -40 C). These pumps are like $50 max and they have decent flow rates at that price.