blending down to bottle proof

[daveflintstone]

When adding water to get your neutral down to 80 proof vodka, what are you using to do the mixing?

I guess it would be the same process with rum.

I have these 1600 gallon tanks (oversized, I plan to put no more than 1200 gallons in them) and don't know if I need a costly tank mixer to mount on the side, or if there's another way.

[rich phillips]

When adding water to get your neutral down to 80 proof vodka, what are you using to do the mixing?

I guess it would be the same process with rum.

I have these 1600 gallon tanks (oversized, I plan to put no more than 1200 gallons in them) and don't know if I need a costly tank mixer to mount on the side, or if there's another way.

We just use a pump to recirculate it for awhile and then let it rest overnight.

[wineslinger]

We just use a pump to recirculate it for awhile and then let it rest overnight.

I'm with Rich. Just clean your hoses well and hook a pump to your bottom most valve and "pump over" the top of the tank for a half an hour or so. Take readings from the top and bottom of the tank to check your mixture. Done.

[daveflintstone]

I'm with Rich. Just clean your hoses well and hook a pump to your bottom most valve and "pump over" the top of the tank for a half an hour or so. Take readings from the top and bottom of the tank to check your mixture. Done.

This seems to be the consensus, makes sense, and thank you muchly.

[Beauport Bob]

Dave, with that volume and about 20% headroom, and only because it has not been mentioned, you may want to do a "step down" series of dilutions. One and one sometimes does not equal two. One dilution to get close, then another to get finer. There may be another thread on this subject. Any comments out there?

[coop]

Dave, with that volume and about 20% headroom, and only because it has not been mentioned, you may want to do a "step down" series of dilutions. One and one sometimes does not equal two. One dilution to get close, then another to get finer. There may be another thread on this subject. Any comments out there?

I call it sneaking up to proof. I get my correct proof by diluting short at least three times. Each time you add water everything changes mainly temperature. I add water, mix, let set for an hour or so. Then take another set of readings, make temperature adjustment to get proof at 60F. Re calculate, add more water and so on. Coop

[daveflintstone]

Wow, that is something I never thought or considered. I assumed if I blended by weight using the correct formulas (I've got Payton's alcohol blending software) that would be that. I don't understand how diluting in multiple steps will give different component weights. I thought weight is independent of temperature?

[daveflintstone]

I found a device called a mixing eductor, which is basically a nozzle that increases the flow rate of a pump by 3-5 times. By mounting this in the mixing tank, a small pump can mix with the capacity of a much larger one. My 40gpm pump becomes a 200gpm mixer, turning over a full 1600 gallon tank every 8 minutes. It is brilliant, and inexpensive. I've ordered one and I'll report back with the results.

[Charles@AEppelTreow]

Weight/mass is independent of temperature. Apparent proof is not. Alcohol and water don't form an 'ideal' solution - which shows up in two ways: 1) the simple solution equations don't match experimental data perfectly and 2) mixing is exothermic - it warms up. That's the simplest sign that your equations aren't going to be perfect - the temperature changes.

If your equations are good enough (possible - it's a very well studied system) and your measurements are good enough (only maybe), you might be able to do it in one shot. But it's easy to drive close in and then putt the last little bit.

[DrewKulsveen]

All of our tanks have air spargers in them. We only need to agitate for a minute or two. As far as dilution goes, we use a pretty simple formula. Here's an example. The volume needs to be corrected for temperature variance by referencing table 7 in the gauging manual prior to reduction.

Pre-diluted spirit proof=130. Wine gallons=500. To get down to 80 proof multiply your wine gallons by your proof (500x130%). This is your total proof gallons(650). Divide your total proof gallons by your desired bottling proof (650/80%). This will give you your total volume (812.5). Subtract the total volume by your original volume (812.5-500). This is the total volume of water that needs to be added in order to achieve your desired bottling strength (312.5). Our tanks have flow meters on the water lines which totalize the water added and volumetric gauges on the side walls. We always set our tanks a tenth or two high since we use a vacuum filler and we lose a couple of tenths proof when filling.

[daveflintstone]

Pre-diluted spirit proof=130. Wine gallons=500. To get down to 80 proof multiply your wine gallons by your proof (500x130%). This is your total proof gallons(650). Divide your total proof gallons by your desired bottling proof (650/80%). This will give you your total volume (812.5). Subtract the total volume by your original volume (812.5-500). This is the total volume of water that needs to be added in order to achieve your desired bottling strength (312.5).

Drew, I believe this calculation is not taking into account the contraction of the ethanol/water mixture. Are you not going to need more water than that? My calculation is 322.33 gallons, not 312.5. Am I missing something (which would not be unusual)?

btw, anyone know of a source for a small air sparger/bubble mixer, like 500 gallon size?

[Denver Distiller]

Our tanks have flow meters on the water lines which totalize the water added and volumetric gauges on the side walls. We always set our tanks a tenth or two high since we use a vacuum filler and we lose a couple of tenths proof when filling.

I'm curious as to your choice of vacuum fillers, though. Why vacuum? Speed? Have you changed fillers? Or are you using equipment from the 80's?

Cheers.

[H-D]

I found a device called a mixing eductor...

...I've ordered one and I'll report back with the results.

So how did it work out? I'm finding alcohol and water don't mix as easily as you'd think. We're using a pump to recirculate top to bottom, but still sometimes find samples at top are higher than samples at the bottom (like a 0.5 proof difference) if it's not recirculated long enough. Maybe an eductor can create even more agitation to help with the process?