Collection Rate Drop-off

[Taco]

Hello,
I'm running a SS keg pot still with a trashcan as my double boiler. When I start collecting on my stripping run it comes out at about 1L/hr but somewhere between hour 1-3 it drops down to about 1ooML/hr. The ABV stays pretty steady between 45%-50%. What am I doing wrong? At this rate I figure it will take me about 36 hours to collect the rest of what I need.

[rubber duck]

Hello taco,

A little more info would be helpfull in diagnoseing you problem.

What is your still capacity, condecer output tube diameter, the kind of wash, aprox abv of the wash, heat source, and how fast are you trying to run the still? Double boilers take a lot of heat that might be your problem but more info would be good.

[Taco]

Hi,
-Capacity is 15.5 Gal it's got about 6.5 gal in it
-Condencer is 3/8"
-Plum Wash
-Heat Source is Propane
-As fast as it will go

It's got about 10Gal of water in the can and 6.5 in the pot. My collection rate is at about 1 drip every 5 seconds now.

I'm distilling on the fruit. Last time I did this without the water bath I did some pretty nasty scorching. If I go the Sans-waterbath route what is the best way to avoid scorching?

Thank you

[noobsauce]

Thugh i use electric....perhaps what you could do is what i do to buffer the cycling of an electric element. i use a steel plate i got made that is 1/2" thick and the diameter of the element. Perhaps if you run without the double boiler and use a plate between the flame and your still, and the flame on low (or whatever works) it might get rid of the scorching problem. I open my suggestion to others more knowledgable for answers.

[rad14701]

I'd say you're not getting enough heat to the wash... It can be difficult to get efficient heat transfer using water in an open double boiler... Just a hunch...

[kiwistiller]

that makes sense, rad, as the still would need more energy to retail the boil as the alcohol content drops... is the double boiler insulated? you could use something other than water entirely...

[rubber duck]

Im thinking that your not getting enough heat, thats a lot liquid. You might need to run some kind of food grade anti-freeze in your boiling pot. Whats happening is that your water is evaporating as it boils and all the energy (heat) is being wasted.

What I would do is run a simple sugar or rum wash without the double boiler, that will give you a good base line on how you still runs.

If that works well and you realy want a double boiler a big banjo berner might get you up to temp and would be more strait forward the messing around with a bunch of expensive cemicals. Even if the burner doesn't work there realy nice to have so you probly won't regret the 70 dollar investment.

[Dnderhead]

not going to do it,, unless it is closed,, as water boils at 212f (100c) no mater what you do.
it will be long and slow----------------to git above that you need pressur , or add somthing to rise boiling point.

[Hack]

On my rig it's normal for the collection rate to drop as the run progresses. I see it as a good sign. I've always assumed that as the run progresses there is less alcohol in the wash so there will be less vapor coming off towards the end. I've got a fifteen gallon keg boiler with a self filling thumper. The self filling thumper is in a water bath that is heated by the incoming vapor before it enters the thumper. However, my collection rate starts at over a gallon an hour and drops from there.

You might not be getting enough heat. If you want to use a water jacket, it should be kept as small as possible or it will sink too much heat. My water jacket is buffering a spirit run on my thumper, which is good, but that's not so desireable on a stripping run.

Another thing to look at if you want a better collection rate is the diameter of the most restricted part of your vapor path. Increasing that will increase your take off rate. Also starting with a larger column and lyne arm that gradually steps down or tapers to the smaller size makes a difference too.

[blanikdog]

... Another thing to look at if you want a better collection rate is the diameter of the most restricted part of your vapor path. Increasing that will increase your take off rate. Also starting with a larger column and lyne arm that gradually steps down or tapers to the smaller size makes a difference too.

What Hack says here is true beyond belief. My original inherited still was a ball tearer with 3/8" diameter column and lyne arm running into a 3/8" coil in a bucket condenser. It took me something like eight to nine hours to run a 25litre wash. I never posted a pic as it was embarressing after seeing some of the other pics in here.

I rebuilt the bugger and it now has a 2" column tapering down to 3/4" into a 3/4" coil in a bucket. My output is now less than half that time, and I suspect produces a better likker!!!

I may even polish it up one day and put a pic up, except I would rather make likker that waste time polishing copper.

blanik