I have noticed over the past week or so there are a few folks inquring about valved refulx. I am one of them! So, because I am building one and am still quite unclear as well as all the diff things come up. Let's, whor are interested do our research and share our understanding. We have established that the condensor to the vr does in fact not have a cap on the condensor. I am coming from a pot man. Now I am reading comments on here about reflux (I assume internal) and folks are talking about the need to control the temp to the tower with water. The plans I have mention nothin about water to the colume of a VR set up. Did I miss something in my plans or does a VR not require water to the column to control this temp you'al are referring to? Any advice?

Do not confuse control with efficiency. The valved reflux gives you the most control, but that does not make it more efficient. And, it also does not come without its own drawbacks.

Hi fatboylo,



I'm compelled to throw in my two cents on this one ... only because I actually tried it and did not find it to be the panacea claimed by so many who never actually tried it. Apparently this is a very sensitive subject for some folks ... but I'll continue with my heretical statements anyway.

I insulated the column on several spirit runs (PS2 HC). In each run I used identical charges -- same abv, same volume, same recipe (low wines from a Birdwatcher's sugar wash). Each time my abv was 2 - 4 points lower. To make matters worse, the heads were clearly smeared into my hearts.

In order for a column to separate fractions you need to have different temperatures along its length -- the hot end at the boiler and cooler end near the column condenser. This difference in temperature (the temperature differential) is what leads to separation. When in full reflux, the vapor travels up the column until it reaches a temperature where it condenses, then it drips back down. As it travels back down it reaches a temperature where if flashes off again and begins its trip back up the column ... and the cycle continues -- reflux. Fortunately for us, the different components have different boiling points, so the more volatile components (esters) will accumulate at the top of the column where it is cooler, and the less volatile components (fusel alcohols) will accumulate at the bottom -- and we get our separation.

Energy loss is the reason we get different temperatures along the length of the column. A still is just a system of heat exchangers. Fire/hotplate -> boiler -> wash -> vapor -> product condenser. The column itself is like a length of a baseboard heating pipe ... it gives off heat to the surrounding air. So the further you travel away from the heat source, the more energy you loose (temperature decreases) -- and we get our temperature differential. If the cost of energy, materials, labor and space was zero, and we had an unlimited source of heat we could just build these huge columns and get outstanding results -- with each component cleanly separated along the huge length of the column. But we all live in the real world where our columns are typically less than three or four feet.

Now enter insulation. By definition, it's a material that prevents energy transfer (whether electric, thermal, whatever). When you insulate the column you are preventing the energy from escaping along its length. This means the temperature doesn't drop much. If it was an ideal (perfect) insulator, zero energy would escape -- the temperature at the bottom of the column would be the same as the temperature at the top -- and the column would loose its ability to separate. It's like the length of the column was shortened.

Now I can imagine situations where _some_ insulation would be useful. For example, if you're running your rig in a windy area ... or in an unheated shed during the winter. Basically in situations where the column is truly loosing too much energy.

So all that said, my recommendation is don't use any insulation unless you really need it.

Regards,
--JB

Hear hear..well said. Same way as BH Rick splained it last winter when I was trying to figger out if all the exspurts recommending insulating the column actually knew sheet from shineola. Believe the words Rick used was.."Insulating the column makes the reflux mechanism work harder." Or something highly similar to that.

Thanks very informative. Is there any way on a typical designed home built valved refluxer...operated in a standard manner..that the purity of output could be ranked say in comparison to a pot still with a thumper..or maybe twice through a pot still etc? Thinking the true test of its efficiency would be the ABV of the finished product. The weaker the more impurity perhaps? And thusly more flavor? Wonder if anybody knows where they top out on the ABV levels? If this aint right kindly correct my thinking. What changes could be made to turn it into a VM? Or maybe it is already a VM. Who knows?

Sure..my old chum from Whiskeyta Falls and some of his pals built one eggxactly as according to the blueprint. He say it spit out Everclear all day long. This was after all his kin who have Phd's and over good stuff in chemistry and Inuneering had gave a thumbs up to the design. Trick seems to be finding some way to get the collection jar up close to the spout where the good stuff comes out. Ladder be the simplest method. You figger a tall column sitting on a turkey burner and beer keg puts it at tree top level..lol. I got a pic of some them trying to reach it. Looked like Rube Goldberg contration..a short step ladder..4 ice chests..and a potted plant or something like that. Might be good to pickle some copper tubing and bring it back down to earth. Also..highly suggest a remote bbq temp checker gauge in hand before starting work on the metal. I would not like to climb up 12 feet to read a steenken gauge..lol. I have a phobia about high places. Thats why when riding on an airplane I have to be real drunk. Never know when the wing is going to come off and stuff like that. PS: Blush blush..had must of forget you was going electric on the keg. That should cut it down to size and make it about a thousand times safer I think. Insulate the keg..including the bottom Its called Reflextic or similar..lol.