Vapor management take off rates question

[copperlover1]

Hello all. I am looking to see what I need to change to increase my take off rate. Currently running 2" VM . 2' packed with ss scrubies. 1" take off to 1" gate valve reduced to 1/2 condenser. 15 gallon keg on propane burner. Run time. 15 gallon gerber wash fermented to very dry wine. 1 hour heat up to temp. Reduce heat to 1/4 open gas valve.15 minutes stabilize.take off fore shots. Close and 15 minutes stabilize. Open gate valve all the way. Collect about 7/8 qt per hour at 95%. Collect about 6-1/2 qts at 95% and temp never changes once. Temp goes up proof goes down end of run. So what can I change to get a better take off rate?

[Bushman]

Diameter equals speed, height purity. I ran a 2" VM for years and a typical 11-12 gallon charge would take between 12-17 hours depending on how I ran it. I went to a 4" CM and my runs are 3-5 hours with the same charge.

[DAD300]

The closer your takeoff dia gets to the column dia will allow for higher takeoff.

You are currently operating at approx 4:1, reflux: takeoff, max.

A 2" column with a 2" takeoff will allow approx 1:1 reflux:takeoff.

[skow69]

when the vapor gets to the tee the stream splits in proportion to the size of the pipes. You are giving it a choice of a 1" to product takeoff or a 2" to the reflx condenser.
1" cross section = 0.79sq.in.
2" cross section = 3.14sq.in.
So 80% of your vapor is going up to the RC and back down the column. 20% is going out the takeoff.
So you can
1) increase the takeoff cross section,
2) restrict the path to the RC, or
3) create some turbulance and hope for the best.

Frankly, I think your 7 - 8 qts. per hour estimate is pretty optimistic.

[copperlover1]

That's a fraction 7/8 ths of a quart per hour. Sorry. I am really just looking to hit maybe 1-1/2 qts per hr. I would like to start after I eat breakfast and finish before I eat dinner.

[skow69]

Oh, in that case it's just depressing.

Sorry, but your options are still the same. You're just not taking off much product. Bumping up to a 2" takeoff valve would probably better than double your output.

[skow69]

Or you could probably get almost the same improvement and save a few bucks by replacing your 2x2x1 tee with a 1x1x1 and two 2x1 reducers. Know what I mean?

[DAD300]

Oh, in that case it's just depressing.

You made me laugh...sorry...

If you had the 2" takeoff, you would get close to 2 quarts an hour.

Dumping the valve and it's restriction would help a little, but would require you rework the top to CCVM.

[bearriver]

Or you could probably get almost the same improvement and save a few bucks by replacing your 2x2x1 tee with a 1x1x1 and two 2x1 reducers. Know what I mean?

I would go with this design. Hookline has pictures of it in his pdf file "Some still drawings", for the visual learners.

7/8 of a quart per hour is very slow, but the reasons for that have been explained well. Address those design changes and see where that gets you. If it's still not enough then start fresh and build a larger diameter column.

Experimenting with different packing arrangements would be a good thing also. Rad gets impressive takeoff rates from a tiny column using marbles.

[still_stirrin]

The closer your takeoff dia gets to the column dia will allow for higher takeoff.

You are currently operating at approx 4:1, reflux: takeoff, max.

A 2" column with a 2" takeoff will allow approx 1:1 reflux:takeoff.

Hey, I'm thinking that area is pi x R squared. So the minimum reflux ratio from 2" to 1/2" is 1/(1/4)squared = 16:1 (I think, if my math is correct).

My 2" to 1" has a minimum RR of 1/(1/2)^2 = 4:1.

No wonder your take off is so slow.
ss

[copperlover1]

Just want to say thanks. To everyone who replyed with all the great info. I am thinking CCVM. No valve to buy and I have lots of 2" copper to work with. Will I have to make my take off condenser bigger?

[hellbilly007]

Your 1" take off valve is being choked down by your 3/4" over 1/2" liebeg. If you increase the diameter of your condensor to 1" it will increase your take off. By the time you buy the fittings to build a larger condensor you could build a CCVM for less and have even faster take off.

[copperlover1]

Won't I need a bigger Liebig on my take off with a CCVM?

[still_stirrin]

Won't I need a bigger Liebig on my take off with a CCVM?

Possibly, if you're trying to minimize the reflux ratio.

My VM runs 2" column to 1 1/2" takeoff then reduces to 1" through the control valve. From there it's 1" to the 7 x 3/8" shotgun. I can run it at 1 pint every 12 minutes with a 2kW input.

So you may need a faster (larger diameter) product condenser input, if you want to run faster. Size matters! (in this case).
ss

[hellbilly007]

Yes, you'll need a larger diameter condensor. I forgot to mention that earlier. A 2" shotgun condensor would be ideal.

If you're not looking to get too involved, a larger diameter liebeg with copper scrubbie stuffed inside would a quick fix for running faster.

[T-Pee]

Don't forget some kind of turbulator inside the external jacket and a bit of scrubbie inside the takeoff line.

tp

[DAD300]

No you don't need to increase the dia of your liebig. However if your takeoff increases to something your PC can't condense, you may need to increase the length.

Keep the inside dia of the takeoff 2" from "T" to 90 deg elbow...once you make the drop from 2" elbow the dia becomes of little importance. Keep the horizontal out of the "T" as short as possible.

As the vapor cools and collapses to liquid it actually helps evacuate it through the Product Condenser and the size is less relevant.

I have used the same condenser(s) on 2", 3" and 4". The condenser is not a restriction.

My 4" CCVM is 4" from column to 90 deg elbow down. 4"-2" reducer to Product condenser and 1/2" out of product condenser. Nothing past the downward bend will slow the vapor or liquid.

[rad14701]

VM branch sizing is only critical before the product condenser... If the product condenser is efficient enough for the amount of heat remaining in the take off branch then size is irrelevant... But if the path to the condenser is restricted for any reason, that is the contributing factor when it comes to the maximum output... So if you can get enough vapor to the 3/4" over 1/2" product liebig it will knock it down efficiently, just like they do when running stripping runs with a pot still ...

[hellbilly007]

My apologies Copperlover1, I stand corrected. Thanks DAD and Rad for chiming in. I didn't consider the vapor collapsing.

[copperlover1]

No problem. Going to mill out a 2" hole where my 1" hole is. Solder in 2" pipe. Than reduce down to my Liebig. Than remove the reflux condenser and replace with just an extension pipe that I will put in a wound up condenser that I can slide up and down. Big question. I have been looking and can see where to put the thermometer. Do I need 2. One on the take off and one in the column ? Will do a drawing first.

[bellybuster]

I'm incredibly impressed you get 95% from 2' of column. You speed things up I bet you'll lose those impressive numbers

[copperlover1]

I couldn't believe it either. But that what my alcohlometer read. The hearts were super clean too. It's awesome when you go to smell in the jar and you bump you lips to it. Alchol Feels like is walking across them it so lite an clean

[copperlover1]

Ok going to try this first. Mill the 2" hole in the side of my tee . 2" to 1" valve than Liebig . Thermometer in takeoff section. Marbles in column instead of ss scrubies.

[Bushman]

I'm incredibly impressed you get 95% from 2' of column. You speed things up I bet you'll lose those impressive numbers

True about speeding things up. I have a 2" VM and getting 95% is pretty typical when running it properly, much easier than my 4" CM.

[DAD300]

Your new drawing is an improvement, but not much.

1-to get the greatest benefit from the 2" takeoff, you need to make the downward turn in 2".
2-if the valve is lower, after the bend, it will pool some amount of liquid when closed.
3-switching to marbles will require longer equilizing/refluxing to maintain the high ABV, thus again slowing your takeoff. Basically you'll be closing the valve down to offset the reduce column resolution.

[skow69]

+1.
You're still at 4:1 reflux ratio. Hence no improvement.

It wouldn't be hard to chuck the valve and make a slideable coil. Stay 2" to the elbow. Probably get 1/2 gallon per hour.

[rad14701]

Marbles may or may not work well in your modified column but nothing venture, nothing gained... Marbles are fairly inexpensive and can be used for decoration when no in use... My extras are in a fancy wire basket on the entertainment center in the living room...

[copperlover1]

Going with the 2" take off. 2" elbow. Easy flange to my old condenser. I will have to get some ss gas line to make the adjustable condenser.

[hellbilly007]

Damn you move quick, lol. That's a nice shotgun condenser, If you wish, you can use a 2" to 1/2" as opposed to the 2" to 1" you mention in your pic, it will make the output stream easier to direct. If you already have the reducer you've mentioned disregard that last sentence. Your ambition is making me feel like a major slacker here.

[copperlover1]

All soldered up and ready for the next step. Reflux condenser. Going with ss flex gas line.