First run using LPG - a question

[Glyn]

Tomorrow will be my first run using LPG. Until now I've been an internal electric element (2kW) but am wanting more control for my spirit runs.
My pot is a 50L stainless keg.

Tomorrows run will be a stripping run with my pot still head. Planning on having a play around to get used to the gas...

My question comes when it's time to do a spirit run.

How do you know how much heat you're pumping in?
Obviously I can see the flame if I bend down, i can see it getting bigger and smaller as I turn the gas up and down.

But what does a 1kW flame look like?
What about a 750W flame? and a 1.5kW flame?

I could measure output from the still and calculate heat input from there (presuming I knew the reflux ratio) to get a gauge for things. Is this how everyone else has done it?

Cheers

[blanikdog]

Certainly not how I do it. I gauge the heat by the sound of the boil chips rattling and the outflow from the condenser and have no idea whether it's a one kw flame or 50,000 kw. What is important is the product coming out of the condenser, nothing else matters, but then I only single runs.

I've never thought about it mainly as I think what we do is an art/craft, not a science. I'll be interested myself to see how others judge a flame.

[Kentucky shinner]

If I were you i would start with the burner about 1/2 throttle when it get hot and starts to boil you may want to turn it down to just a simmer. It just takes a little OJT as you go.. after one run you will have a better idea of how to adjust your flame..
KS

[blanikdog]

This is where the boil chips help. You can hear the rattle and learn about how YOUR still works. They're all different.

Stay Safe

[Braz]

What KS said.

With my reflux I start with a medium flame and once it comes up to temp I back the flame way down to a simmer. That is still enough heat to keep things running till the very end.

For stripping runs with the pot I don't back it down quite as far and run a bit hot and fast.

But each one is different.

[Pooyan]

Until now I've been an internal electric element (2kW) but am wanting more control for my spirit runs.

Hi Glyn,

Have you considered using a powercontroller to control the output to your electric element?
You can buy one or build it yourself for a lot less $$$, see the schematics in the Related Hardware and Appurtenances section...

Pooyan

[dag_nabberit]

On a pot still I gauge the flame by the outflow from the condenser, like Blanikdog said, its more of an art than a science at that point. Adjust for the flow you want by the amount of heat applied. On a spirit run, slow and easy works for me. I don't need to know specific numbers.

[ozone39]

I have a temperature gauge that measures wash temperature (14" needle gauge). Specifically meant for start up, after that (boiling) it's useless.....

[blind drunk]

I could measure output from the still and calculate heat input from there (presuming I knew the reflux ratio) to get a gauge for things. Is this how everyone else has done it?

I use the heads portion of the run to figure out the flame and the flow rate. You got a little bit of time. I sometimes measure the volume by measuring the time it takes to fill a 700 ml bottle. Then I either turn it up or down, depending on what I think I'm tasting and smelling. By the time I get to the heart of the matter, I shot for that thin pencil lead stream that blanik's talked about in another post. Also like others have said, the rattling copper chips is another element of the whole picture. Taste, smell, feel (I don't get this part), look, measure, listen. Good luck, bd.

[Ayay]

With a pot still -
Strippin is full blast up to the limits of the condenser.
A spirit run is directly controlled by the heat input. (As Dag and others have said). Full-blast to heat up, then adjust heat to get the desired output. First drips are best very slow with the heat turned very low, say 1 drip/sec to get the foreshots and early heads out. After that you are the chef! There's not much else you can adjust other than the heat and there are no set numbers to go by, but fine heat control is essential.

[Glyn]

Thanks for the replies guys. it helped alot.

Pooyan - I did consider a power controller, but after the 7.1 mag earthquake we has a couple weeks back I decided I needed some gas to cook on if power went out again. This kills two birds with one stone. A power controller still isn't out of the question.

[Mr.Spooky]

here lately,, and for the most part, i only do a single run. ill crank that mother up to where it sounds like a jet airplain. i run about 12 gals or so, so it usually takess about 30 min to get the stream flowing. as soon as it starts the steady flow, ill back the heat way down to where you can bairley hear the flame. after about 5 min, it might start on drips, and at that point i just finness the heat to get it where i want it. all of this hapens before i get to the first 300 mls.. then i toss that 300mls and start collecting (i wont touch the heat again until i get to tails then i crank it back up and pull tails.)
each time i adjust the flame,, ill give it about 4 or5 minuets before touching it again,, just to give it time to do what its gonna do.
spooky

[heynonny]

I use a welding gas regulator as they seem to have a finer adjustment (for fine-tuning). Max output for this reg is 20+- psi, which heats 12-13 gallons in about 30-35 minutes. When the thermometer temp starts to 'run', I turn down the (regulator) heat and "then" open the valve (a tapered plug valve) to the 0-5 psi gauge and use that for fine temp control. I dont know exactly what the pressure is, but for me, reading about 1 to 1.25 psi works with the pot still and reading about 0.75 psi with my column works fine. The copper 'schrapnel' rattles gently in the boiler at these settings. One good thing about this setup is that (especially in winter/cold weather), as propane is used, the temp in the tank drops along with propane pressure, and the low gauge reacts quickly. I must chase the temp for 10 minutes or so till things stablize, then maybe every 15-20 minutes a small adjustment, cold weather maybe every 10-15 min. to maintain a steady output. (And for the "A K's" out there, yes I checked for leaks, more than once) -hey-