Help Needed with Nixon Stone Head operation - Finicky

[varocketry]

All:

I am running my first actual spirit run on the Nixon Stone head tonight, so I thought I'd check-in with you on operating procedures. Pic1 shows the head as completed.

Pic 2 shows the stabilization period at 174 degrees about 24 minutes in.

I picked 175deg as I saw this temp used in a Youtube video demo of a Nixon Stone head.
Bizarre! I collected a little more than a1/2 half pint of FORES as I was typing my email.
I switched over to a larger collection jar and almost immediately the drip stream seemed to virtually stop, just a few drops a second. I look at the temperature and its 202 degreesF.

I was running at 10Amps or about 2400 watts through the stabilization period at a steady 175 degrees.
Anything above virtually off causes the temp to spike up again. The stream was still low. Very finicky and at this rate would take hours to work through the 11 gal charge.

So I decided to stop, to run it with the POT STILL tomorrow, as I understand how to operate the pot still. I don't yet understand the NS head operation and how to manage it. Any tips you might provide would be Most helpful. Would anyone care to mentor me on learning this NS Head operation?

VARocketry

PS 1) The 3/8" needle valve has a very small orifice, it seems like it substantially constrict flow even in wide open position.
2) the double coil in the head is made with 1/4 tubing. The Coolant flow is not great through it. The outflow water is warm to touch so its doing some knockdown, no doubt.

3) What are the operating inputs to using this design? What should I be trying to manage and how?

[skow69]

Are you sure you didn't have a leak? The only good reason I can see for the temp to go to 202 is if the charge ran out of alcohol. A temperature spike for me is jumping from 172.2 to 172.5. I never collect anything over ~178, that's just the rank tails at the end of a run.

How big was your charge and what was the ABV?

[still_stirrin]

A Nixon-Stone is a LM reflux head (similar to the Bokakob). So, the needle valve is used to regulate the reflux ratio by the liquid take off rate. Close the valve (zero liquid take off), and your reflux ratio goes (theoretically) infinite, since all of the vapor going up the column is being condensed and returned to the packed column.

You didn't say what your boiler charge was, but I assume it was NOT low wines. A LM head should be fine to get you 170-180 proof from a normal wash (around 10% ABV). You'll be able to easily pull 190 proof from a low wines charge as well.

I believe your problem is that you're trying to use your thermometer to tell you how to set the valves. If your reflux condenser can handle your heat input, you should be able to sit there with the liquid valve closed and the still will run in full reflux. As you open the liquid valve, you'll get a steady stream of liquid out. You set the stream size to keep the reflux up, yet take off some of the liquid.

It may help turning the heat up a little when the valve is cracked and see if you start to get a (steady) stream out. But your limiting factor will probably be the reflux condenser.

You said you were pushing 2kW (or more) into the boiler. How big is your column? What is the packing? I rarely need a full 2kW for my 2" x 1 meter glass marble packed column and LM to get azeo (from low wines). But, that is close to the desired power for a 2" (39" tall) column according to the calculator on the parent site. So, you've got to be close.

I suspect that much, if not most of your liquid is returning to the column via the liquid return line. So, try increasing heat and reflux cooling power and then open the LM valve a bit until you get the pencil lead size stream out. And don't fret so much about your thermometer readings.
ss

[varocketry]

skow69 - Please explain how you set, achieve, and maintain 172F? Are you changing power input to do that? What's your starting and stopping temps? What temp do you stabilize at? Do you change power input during the takeoff?

Still_stirrin - thank for your thoughts. Here's the answers.

My boiler charge was ~11 gallons of all grain fermented wash. My Ph pen broke but the grain calculation was for an Expected-OG of 1.07.
It finished at 1.04 and wouldnt go lower (hydrometer measurement floating in the wash).

This was my first charge run. I was using the thermometer to regulate the column temperature to stabilize for 40 minutes as I saw in a YOUTUBE video by Olympic Distillers
https://www.youtube.com/watch?v=rpZdQrvLYCw" onclick="window.open(this.href);return false;" rel="nofollow
at 3:56

I do not yet understand what temperature(s) I should be working with - starting , finishing, etc. I haven't been able to find a guide on this topic.

Column height: My packed column is 39" in length. In the picture its the black insulated section below the triclamp.

There's about nine inches of unpacked column above that in the head.
The packing is tightly rolled copper mesh. I could blow through it and water pours through it readily (cleaning).

I am using a double coil condenser coil in the offset head made from 1/4 tubing. That tubing size substantially restricts the water flow; in being much more than out. The output water is warm to touch.
When I open the needle valve, I get a very small sputtering stream.

[bluefish_dist]

1.04 is really high for a finished gravity. I would guess it had not really finished and was stuck due to temp or Ph crash. Most of my runs will finish under 1.00 if I do my part on keeping the yeast happy.
I run a lm takeoff and have never seen a temp jump like that. my head temp at full reflux will run between 163 and 164 depending on the day (6000ft). If it even goes up 1 deg I am well into the tails. I do run by temp as it is a pretty direct relation to abv, But it does change depending on atmospheric pressure, so high pressures will raise the temp and lows will lower it. Also temp (.1 resolution) is not accurate enough to show 191 proof vs 190 proof. for reference, 170 proof is 170 deg for me. So 20 proof change is 6 or 7 deg F change.

[varocketry]

@bluefish - agreed, I think I had a Ph crash. My Ph Pen crapped out and I had no way to determine the actual Ph. Ive since replaced it with another bought off EBAY. And I bought some Chinese Ph Paper that measures 1-10. It read 4 when I tested some of the mash.

Can you take a moment to explain how you get to 163 F? How you operate your LM rig? What you're doing or monitoring? Do you stabilize at some temp in full reflux for some time? My measured temps seem totally dependent on power input --- more power makes the column temp go up., less power makes it go down. I don't have any feel, yet, for the proper operating steps.

Have you picked 163F for some reason? Is that your expected temp for alcohol vapors to appear to be condensed?

Thanks, bluefish, in advance for your time.

[skow69]

Var, so you were running a wash about 4% ABV. That probably explains the crazy high temperature. The way the temp varies with the power input makes me suspect that you are not heating enough to keep a steady boil going. That would also explain why you can only get a drippy output.

99% of all discussions about LM operation are based on charging the boiler with low wines at 25% - 40%. We mostly strip the wash so we can run low wines. You won't find any guides for running a 4% wash, all heat settings, temps, and outputs will be different.

I start with maximum power (2625 watts). Once up to temp I reduce power to a safe level, around 1800 w. Typically, the temp will rise to somewhere around 175, then slowly come down a little. The exact numbers aren't critical. Bluefish gets 163, the still in your video stabilized between 180 and 185. We are using the thermometer to monitor changes. The thermometer will always reflect the boiling point of the vapor mixture at that location. More alcohol rich = lower temp. So if my temperature increases, that means that my takeoff is less pure.

I increase the power gradually through the run. I like to keep as much power as possible going in.

I think you could use a refresher course in Home Distillation 101. Read through this a few times and things should start to click for you.
http://homedistiller.org/theory

[bluefish_dist]

First when I say 163 deg for azeo, that is due to my altitude. I run at just over 6000 ft. At 7300 it was in the 161 range. When running lm on my 4" with my big still, I heat up at full power 8kw, then reduce power to about 4kw as I start to boil and send vapor up the column. Small still is 4K to heat and 2k to stabilize even on the 4". I let it stabilize for 30 min to an hour at full reflux depending on how quick the temp settles in. As I stated above temperature varies depending on atmospheric pressure. Usually it will stabilize.3 to .5 deg lower than it will run, so high 162 to low 163. As I start take off I will bring the power input back up about 1 amp every 10 min or so until I get power up to 3500 on the little still and 6000 or so on the big still. I think the big still needs more power since it dissipates more heat to the atmosphere. I run the same still head on both stills.
I adjust the output to hold temp. If temp starts to climb then I reduce output. I know about how much I can turn (1/4 turn open) the valve and hold temp, so that is my starting point. Once I have taken off my fores/heads ~1 gallon or an hour, I switch to the vm side and use the same method to adjust reflux/takeoff. If I am running vodka I also check proof since it has to be over 190. If the proof drops or temp climbs, then I increase reflux. I have found that temp is not accurate enough to tell between 190 and 191. You can get either and still read the same temp. With a more accurate gauge I might be able to run by temp alone. Until then I will also check proof. I don't run a parrot. Thermometer is at the top of the column in the t where it splits to lm or vm.

When running 3 plates I set a temp for the abv I want to hold and adjust reflux when it hits that temp. Depending on the valve I can adjust 1/4 or 1/2 turn each time I hit max temp and then it will drop a deg or less for the next hour until I adjust again. At the end take off slows and temps will no longer hold. Usually I find takeoff drops to 1qt/hr from 1gal/hr and then I stop. There is still some alcohol left, but I have never used the last jar after cuts, so no need to waste the energy to get the alcohol. While I can do all this on the lm side, I find that the vm side is more robust and easier to run.

[varocketry]

Skow69 - thanks, I'll do my homework and read through it several times.

[kimbodious]

really good clear description there bluefish