How can I fix this reflux rig? Expected 94% got 87%.

[jbrew9999]

My new reflux still didn't perform as I had hoped and I would like to know what can be done to tune it up.
Here are the specs from bottom to top:

Boiler: 8Gal ss pot with lid set on and sealed with flour dough.

Heat: 1500W water heater element inside pot.

Minimum water level to cover element: 5.5L

Column: height: 1.5m (60") Diameter: 2" ID (50mm) Insulated with foam pipe insulation

Column Packing: real copper mesh rolled into plugs, wrapped with a ring of copper wire to keep them from unrolling then stuffed into column. 11 5" long plugs for 55" total packing height.

Head: Bokakob based EL (eliptical disk) head with take off valve.

condenser: 16ft of 1/4OD copper in double helix coil stuffed with copper mesh resting in top of head fed by hose water.

The whole thing looks identical to "One Fiesty Old Lady"s new setup shown here -> http://www.photochicken.com/ims/pic/48VLcT7/4468.jpg" onclick="window.open(this.href);return false;" rel="nofollow

From those specs, and the theory and design sections of homedistiller.org, I was expecting to get 95% purity if I ran it slow enough. I didn't want to have to use carbon filtering to clean up the spirits.

The best I got out, at any rate was 87%.

The wash was a sugar wash with 10-12% Aclohol. After 95 minutes to reach boil, I fired up the condenser and let it sit in full reflux for 30 minutes. The temp at the top of the packing stayed at 80C the whole time. I broke my hydrometer just before my first reading so I had to rely on the temp to maintain the quality. I collected 60ml in a double shot glass and then 150 ml in jar 1 and set those asside. Then I started collecting the main body of the run I collected 1.5L slowly adjusting the flowrate to keep the vapor temp at 80C (the same temp as 30 minutes of full reflux) After that, the flow had been turned down to pretty slow so I bumped it up a little and let the temp rise to 88C for another 1.25L before opening the valve a little more and running the last 400ml out at between 88 and 94C. I was never collecting faster than 40min per Liter and usually slower than that. (note that I was closely watching the vapor temp just above the packing) the whole run took about 6 hours total-- 1.5 to heat up and set up, 3.5 - 4 to collect and 1 - 1.5 to clean up.


Everything was clear except the last jar that came out at up to 94C. That one was a little cloudy. There were distinct differences in smell between the first (shot glass), second (150 ml jar), the 3 at 80C, the 3 at 88C, and the last at upto 94C. I played with samples of each in my hands, on a spoon, with fire, diluted with water, and by smell and color and was pretty proud of my self.
It wasn't until a week later when I got a replacement hydrometer that I found out it didn't go as well as I hoped. I measured all the fractions, and adjusted for temperature and then compared to the readings from 2 different store-bought drinks (my hydrometer was reading 4% lower than actual). Then I diluted down one of the 80C pints into a liter of 40% vodka and tested it. It does taste like vodka and doesn't have a cardboard smell but it is much sharper than the other vodka I have. Next, I made up a pint of Liquor quik amaretto and found it to be rougher than I would have liked.


I'm not satisfied with my results. I want to be able to make smooth neutral spirits and my still design *should* be able to do it. What do you guys think?

I know the condenser is working fine, everything that should be sealed is sealed correctly, the valves work, and I can hear reflux overflowing in the head.

My analysis makes me think that my problem(s) HAVE to be with the column and not my process or takeoff rate since I drew off most of the spirit at the lowest temp I could achieve even in full reflux. Looking at the charts on homedistiller I am only getting 2 theoretical plates when my design should have closer to 10.

My reflux return overflow doesn't have a built in drip spout-- it doesnt drip the reflux into the center of the packing (I screwed that up when I installed it) Instead I fit a wire hanging off the center of the lower disk and suspended in the center of the head. I ran water through this and it seemed to work fine-- the water that flowed through the head (as if it was reflux) ran right down my wire and dripped out in the center of the column. That shouldn't have been my problem unless the wire moved out of its place.

My column also doesn't sit perfectly plumb, I had it shimmed to be pretty close to plumb though. Do you think this could be a problem that wastes 8 theoretical plates?

A couple times during the run, I bumped the column and it rocked back and forth quite a bit (becasue of the shims I mentioned above) and everytime I played with the valve, it would rock a little.

So far that is all I have got-- a possible problem with the reflux not flowing evenly down the packing. Can anyone think of anything else? Any other comments on my setup or process?