Reflux condenser with or without SS scrubber

[Iulistoi]

Hello everyone. I need some advices from you.

I have a CCVM column with single coil reflux condenser. The condenser is 35 cm long and has a lot of empty space inside.

I thought that filling that space with something that increases condensing suface would be better. Copper mesh would be even more better because of better heat transfer than SS scrubber.

I tried runing the still without anything in the condenser's hole vs. filled with SS scrubber tight or loose.

The best control of the reflux ratio was when the RC run empty and the hardest to control when with the scrubbers tightly packed (even a few mm up or down would have a huge impact on RR).

Another aspect is I think that some scrubbers inside the hole will aid in dripping the reflux just on the middle of the column packing and prevents it from trikle on the inside wall but this is just an assumption.

So what do you think is better for most efficient and best RR control, with or without packing in the center of coil? The packing shoud be tight or loose?

[Demy]

Generally the scrubber in the coil is used for various things including increasing the contact surface, "braking" the steam at the top so that there are no "preferential ways" for the steam and giving the coil time to condense better, etc. essentially helps to create a non-airtight cap for the vapor. Generally, those who have problems with steam escaping from the top of the column adopt this method even if it cannot work miracles but it never hurts. The important thing is the efficiency of the coil and dose the heating power (the coil must keep pace with the amount of steam that rises along the column).

[Setsumi]

in a ccvm the best efficiency is where you have 100% reflux below take off. if you need to pack your condenser with wool it should not be more than what is below take off,.. if you must have 100% reflux. i am not certain packing the reflux coil with wool helps much. then again it is something that is historicly mentioned in forums

[Prairiepiss]

Seams to me you answered your own question. You stated that you had the best control with no packing. So would that not be the setup you would want to run?

By packing the coils you are actually directing Most of the vapor into the takeoff. With out an easy flow through the coils. The vapor will take the path of least resistance. Which counters the whole purpose of this still design. You need the easy flow past the takeoff into the condenser coils. For the magic to happen. When you put packing in there. You are blocking that flow.

If your reflux condenser can provide 100% reflux Positioned below the takeoff. There is no reason you need any packing in it. If it cannot provide 100% reflux positioned below the takeoff. Then you need to make a bigger better reflux condenser.

Now if you were working with a LM style still. Packing may help with a reflux condenser that may be borderline to small.

[kimbodious]

By all means weave SS scrubbers in and through the reflux condenser coil to maximise contact between it and the column walls. As far as other packing goes leave about a 6” gap between the top of the packing in the column and the lower edge of the outlet for the offtake.

[Tummydoc]

What's your column diameter, and what's your coil made of (ie 1/4 inch soft copper?)? If you can get 100% reflux with the coil advanced and are sure no vapor is escaping the top of the column the I don't see why you're fussing with adding scrubbers.

[Iulistoi]

What's your column diameter, and what's your coil made of (ie 1/4 inch soft copper?)? If you can get 100% reflux with the coil advanced and are sure no vapor is escaping the top of the column the I don't see why you're fussing with adding scrubbers.

The column's diameter is 54mm or 2.12 inch. The coil is 6mm (~1/4 inch) soft copper pipe. The total lenght of the pipe is 6 meters (19.7 ft). The length of the RC is 35cm or 13.8 inch.

Yes, I can run the column on full heating power with 100% reflux. But my obsession is that some vapor could escape through that hole. I always do the mirror test and I don't see or smell something suspect above the column. But the pure alcohol vapor doesn't fog the mirror. The upper half of the deflegmator is cool and slightly above the T zone is almost worm to hot but the top of the column never gets hot. The water exiting from RC is around 50-60 degrees Celsius (120-140° F).

However, don't you think that cooling efficiency could benefit from puting some wire or loose scrubber packing that would create some turbulences? On the other hand, I'm looking for a way of dripping the reflux just in the middle of the column packing without using centering ring that would lead to choking.

Thaks all of you for helping me with your ideas!

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[Prairiepiss]

So you are just worried about something you don’t need to be. If the top of your still is cool to the touch. There isn’t any vapors going to be coming out of it. Stop overthinking it.

As far as redirecting the reflux to the center. You would have to use some sort of mechanical device added to the condenser coils to direct it where you want it. Again impeding good flow and not helping on that end of things.

I personally have found the easiest way to direct the flow through the column is by manipulating the packing so that it directs it towards the center.

But again worried about things you really don’t need to be worried about. If your still is running good and is controllable. There is no reason to mess around with petty things. As long as you have a decent length column. That reflux will move all over that column as it makes its way back down. The need for centering rings and the like. Is mostly for columns that are too short to begin with. Or in pore design to begin with. As in the many badly designed available for purchase from the interwebs.

[StillerBoy]

The need for centering rings and the like. Is mostly for columns that are too short to begin with. Or in pore design to begin with. As in the many badly designed available for purchase from the interwebs.

10-4 on centering rings.. totally useless on small column..

Mars

[Iulistoi]

So you are just worried about something you don’t need to be. If the top of your still is cool to the touch. There isn’t any vapors going to be coming out of it. Stop overthinking it.

As far as redirecting the reflux to the center. You would have to use some sort of mechanical device added to the condenser coils to direct it where you want it. Again impeding good flow and not helping on that end of things.

I personally have found the easiest way to direct the flow through the column is by manipulating the packing so that it directs it towards the center.

But again worried about things you really don’t need to be worried about. If your still is running good and is controllable. There is no reason to mess around with petty things. As long as you have a decent length column. That reflux will move all over that column as it makes its way back down. The need for centering rings and the like. Is mostly for columns that are too short to begin with. Or in pore design to begin with. As in the many badly designed available for purchase from the interwebs.

You gave me a lot more confidence.
Yes I have a decent packing length, 120cm (47 inch) filled with 435 g (15.3 oz) SS scrubbers and the total length is about 177cm (70 inch), so enough height I think.

I thought there always may be more improvements to make but the things seem to work well.

[Prairiepiss]

Don’t fix it if it ain’t broke. Or you end up fixing it till it’s broke.

That’s plenty of column.

I use the Round copper scrubbers. I kinda roll them into themselves. Kinda turn it into a bowl. And I insert them so the bowl is up to catch the dripins from the one above. I try not to smash them together. So they kinda act as a centering ring themselves. You can do the same thing with the rolled stuff. If you roll it so the center comes out on one end and forms a bowl n the other end. You can place it the same way.

No mater what you do. There will always be reflux running down the walls. In all actuality there is reflux running back down throughout all of it.

Stop worrying about it and think about that next batch you want to make.

[Iulistoi]

Now I have 160 liters (42 galons) of sugar mash fermenting.
I put 32 kg sugar, 4 kg boiled lentils, 3 kg smashed tomatoes, 1 kg wheat bran, 2 kg fresh bakers yeast and a few pills of simethicone for preventing the foam formation. Usualy, it ferments dry within a week at 20°C. Maybe I will distill it this weekend or next week.

I find out that if I add some oil with flour paste it seals better and is easier to clean the still between runnings.

The last time when I run the column I put scrubbers tightly packed in the RC and was hard to control the RR with tendency to drip too fast and drop the abv to 91-93% witch is not satisfying to me.

Two times ago I used a smaller takeoff port, looser packed scrubbers in RC and there was too much reflux and too little collecting speed even with the RC raised high. For me, everything is beyond 95% abv is useless because of very high RR and small collecting speed. I think the optimum is 94-95% abv and a speed of around 1-1.2 liters per hour for my column diameter and heat power.

So I think I should find a balance between the two. Next time I will try the larger takeoff port and put nothing in the RC. Seems that simple ways work best.

[Iulistoi]

I made a new double-helix RC for my CCVM column.
I used 10 meters pipe. The coil is 40 cm long and fits loosely in the 54 mm column.

Do you think that filling the center hole with some copper scrubbers would add some benefits?