Lowering the height of a vodka column but not reducing plates

[Blackheart]

I am running into a challenge with a new building upfit and thought I would throw this to the peanut gallery.

We planned for a roof penetration for our vodka column. The construction is underway. The city engineering revised the roof penetration needs substantially and the cost has now increased a bunch.  

The question becomes easier: spend a ton of money to do a roof penetration or modify equipment to deal with a lower ceiling?

Does anyone have thoughts on making a vodka column lower or dividing it in half?

 

Thanks and cheers! 

[meerkat]

I only have experience with one column where the tray spacing was deliberately made very tight. It was a very difficult column to operate and never achieved its design capacity.  Unless you have a very skilled designer with a proven track record I would stay away from tight tray spacing.

Split columns are common and there are many vendors who can offer you these.  I would be interested in reading how pumping the bottom liquid from the second column to the top of the first to provide its reflux compares with using a dephlegmator to provide the reflux on the first column.

[Blackheart]

Thanks Meerkat.  We live by your software, BTW.  Couldn't function without it.

Re: the 1st vs 2nd column condensate return, I was assuming I would run two deflegs and pump back column 2 into column one.  Seems like an easier challenge to solve than seeing if a simple pump back (sans a defleg on column one) will solve the challenge. 

 

[meerkat]

Pumping the bottoms from the second column to the top of the first is a closer match to a single tall column - but whether it is better or worse than the double defleg arrangement I do not know.

[Silk City Distillers]

Pumped reflux should be able to achieve higher rectification and better energy efficiency than twin dephlegs and dumping reflux from both columns back to the kettle - everything else equal of course.

Twin dephlegs may be more challenging to initial dial in, because you'll be managing temperature control across the two dephlegs independently.    However, if your end product is always neutral - once you've got it dialed in, you aren't necessarily fiddling each run.  This is probably true of either style.

Pumping reflux seems like it should be trivially easy - however there are complexities associated with it, and depending on your jurisdiction factors that can be very costly (explosion proof, etc).

Best advice is to work with someone who has already figured their system out, live and in-production somewhere.

[Southernhighlander]

Pumping the reflux from column 2 back to the top of column 1 gives you functionality equivalent to one vertical column with the same number of plates as the combined columns.  Not pumping the condensate from column 2 back to column 1 gives you around 75% of the plate functionality of 1 vertical column.  We have proven this time after time with testing.  There is no reason to not have a dephlegmator in column 1.  In fact if you plan on ever using column 1 and bypassing column 2 then you must have the dephlegmator in column 1.  Also sometimes just a little coolant flow in the column 1 dephlegmator while pumping back from column 2 will help balance the system and give you higher proof.  Also If you will have split vodka columns I strongly suggest a thermostatic valve to automate the condenser and dephlegmator cooling.  Also you will get much better functionality if you plumb the coolant in series from your final condenser to the last column in line then to the column before that and so on.  Of course if you plumb in series you will need bypasses at each dephlegmator.

It would make things really simple if you could just lower the base of the vodka column to the floor and simply add one of our condensate pump kits.  If you split the column you will need 2 condensate pump kits unless you have the base of column 1 high enough to gravity feed back into the pot.

We have over 50 stills out there using our condensate pump kits on lowered and split columns and they work wonderfully well.  paul@distillery-equipment.com  417-778-6908 ask for Paul.

 

[Blackheart]

Thanks Paul.  I tried to PM you but the system says I cant.  I sent an email offline. Cheers!

[Southernhighlander]

3 hours ago, Blackheart said:

Thanks Paul.  I tried to PM you but the system says I cant.  I sent an email offline. Cheers!

Sorry about the PM thing.  My inbox was full and I didn't realize it.  I deleted some messages so my PM works now.  It was nice talking to you on the phone.  If you purchase our pump kit let us know how well that it works on here, once you get it set up.

 

Thanks.

[whiskeytango]

How much to tall is it?  

If its just a little can you sink the still Into the floor? 

 

[FijiSpirits]

Based on my observations you would need either a return pump that could run dry Or have adjustable metering as return condensate can vary a great deal in two column system. How are you guys solving this Paul?

[Southernhighlander]

3 hours ago, FijiSpirits said:

Based on my observations you would need either a return pump that could run dry Or have adjustable metering as return condensate can vary a great deal in two column system. How are you guys solving this Paul?

Sorry, that's proprietary.  I would rather my competitor's have to do the work that I had to do to figure it out instead of me giving them the info for free.