Help needed. Not properly working boka with propane burner

[Pikey]

I've no doubt a heat shroud would help a bit - although he already has a partial one by virtue of the keg rim.

Please do let us know hoe it turns out

[Yummyrum]

I wonder if any of our members with propane apparatus would like to comment ?

I use a propane gas burner under all my stills ....LOL ...except the LM/VM 2" .I'm a scaredy cat and don't like flames near high ABV alc .
I have a three ring Banjo burner , it came with a standard Gas reg .I upgraded to an HP reg . See HERE ...picture tells a thousand words

I agree with pikey that the keg rim does act as a heat shroud , certainly at the power that you would want to stuck up this . I don't think the distance from the flame to the keg bottom is that much of a deal .The heat is pretty much contained in the keg rim .


But there is no point giving this still anymore power than it has already due to the flooding issues .
Which is my next question .
Why can't the fluid drain back to the boiler ? Is there a mesh or holder in the bottom of the column to hold the packing that is causing a flow issues ? If so , it doesn't need to be there .Scrubbers will hold themselves in place .

[00Speedy]

Hello I am the Owner of Boka,

But my English is unfortunately too bad to discuss here.
"der Wo" trying to help me .

[thecroweater]

One thing that does strike me as a small but significant design faut it the position of the take off valve and that blenky return line. I feel it would be far better to have the valve right against the column and remove that return line altogether. A diagram of the
Internal construction of the head would clear this up straight away

[Deerhunter]

In the first video why does the take-off appear to be spitting the liquid out. Shouldn't there be steady drops or at least a broken or steady pencil lead stream? Appears vapor is pushing liquid out??

[der wo]

I have a three ring Banjo burner , it came with a standard Gas reg .I upgraded to an HP reg . See HERE ...picture tells a thousand words Thanks for the effort.
I agree with pikey that the keg rim does act as a heat shroud , certainly at the power that you would want to stuck up this . I don't think the distance from the flame to the keg bottom is that much of a deal .The heat is pretty much contained in the keg rim .
I don't think he wants to saw the rim off as long there are other causes possible. And generally a longer distance helps against scorching (but will need a shroud or he looses too much propane).
But there is no point giving this still anymore power than it has already due to the flooding issues . Yes
Which is my next question .
Why can't the fluid drain back to the boiler ? Is there a mesh or holder in the bottom of the column to hold the packing that is causing a flow issues ? If so , it doesn't need to be there .Scrubbers will hold themselves in place .

I thought, the packing is too tight in the middle of the column and I gave him instructions to pack it for his next trial. But now I think, perhaps you get the Sherlock Holmes award. He wrote me yesterday he uses this for retaining the scrubbies:

https://www.stilldragon.eu/de/filtersch ... heibe.html
I wouldn't use it for this application. It looks like the holes are too small to allow both vapor up and reflux down. But it's a stilldragon product for example for gin baskets. I think a gin basket should work in reflux mode too. What do you think?

[der wo]

One thing that does strike me as a small but significant design faut it the position of the take off valve and that blenky return line. I feel it would be far better to have the valve right against the column and remove that return line altogether. A diagram of the Internal construction of the head would clear this up straight away

A picture of the return system is in the middle of page 1. He is not the first one using a external return, but perhaps the first one using a pigtail at the end of the return. But for next trials he will remove the return to fix the other problems (mainly flooding) first.

Edit: BTW he wrote me the distance between the plates is 1.5 or 2cm. This is ok I think. The overlapping is 6mm. Perhaps this is not much, but as long there isn't any unwanted reflux over the plates, it works I think.

[Swedish Pride]

2-zoll-filterscheibe.jpg

https://www.stilldragon.eu/de/filtersch ... heibe.html
I wouldn't use it for this application. It looks like the holes are too small to allow both vapor up and reflux down. But it's a stilldragon product for example for gin baskets. I think a gin basket should work in reflux mode too. What do you think?

A lad on the Swedish forums use the 3" version as perfplates and they hold the liquid at bay alright, vapour can come up but he uses a 1/2 downcommer to get return to the keg.

[der wo]

2-zoll-filterscheibe.jpg

https://www.stilldragon.eu/de/filtersch ... heibe.html
I wouldn't use it for this application. It looks like the holes are too small to allow both vapor up and reflux down. But it's a stilldragon product for example for gin baskets. I think a gin basket should work in reflux mode too. What do you think?

A lad on the Swedish forums use the 3" version as perfplates and they hold the liquid at bay alright, vapour can come up but he uses a 1/2 downcommer to get return to the keg.

Thanks a lot. So perhaps he should saw a few larger holes in it and perhaps at least the flooding problem is solved.

[Swedish Pride]

only one way to find out

[der wo]

Here flooding problem with one of the stilldragon filter disks:
https://www.stilldragon.org/discussion/ ... ed-section" onclick="window.open(this.href);return false;" rel="nofollow
Perhaps this is, what Swedish Pride is writing about.

[Yummyrum]

I wouldn't use it for this application. It looks like the holes are too small to allow both vapor up and reflux down. But it's a stilldragon product for example for gin baskets. I think a gin basket should work in reflux mode too. What do you think?

I agree ....It's totally not necessary to hold scrubbers in a column , If they are stuffed in good enough to work well , they hold them selves in place . .......can't comment on that screens use for Gin , never been there , only thing I can think of, is that up the top of a still where the gin basket might be , the ABV will be higher and the "surface tension " will be lower and allow passage through that screen where as at the boiler end , its all low AVB stuff and the surface tension would be higher and restrict easy passage through it ...if that makes sense

Anyways ,.....it looks like we may be one step closer to nailing this bastard

But now I think, perhaps you get the Sherlock Holmes award. He wrote me yesterday he uses this for retaining the scrubbies:

2-zoll-filterscheibe.jpg

https://www.stilldragon.eu/de/filtersch ... heibe.html

Thanks for the Sherlock Holmes award ...all I need now is a chest to pin it to

[00Speedy]

The flooding Problem is solved, i drilled Holes in the Filter Disk .
Thx Yummyrum

[der wo]

Now fixing the unsteady output:
My "easy to fix"-suggestions are:
- 45° angel of the liebig (better division of distillate and air)
- hole in the liebig nearby the valve (the tube has to be angled for this I think)
- hole at the top of the pig tail or removing it

[thecroweater]

hole is the Liebig

[der wo]

hole is the Liebig

Pintoshines idea, here: http://homedistiller.org/forum/viewtopi ... =17&t=6865
This doesn't effect all causes of the problem. But it gives air another easy entrance and exit, the air doesn't have to get pushed through the whole liebig. The distillate will be able to flow faster through the liebig. Perhaps this is enough to fix it.

[00Speedy]

Ok "Wo",

I'll try the following things first:

- hole in the liebig nearby the valve (the tube has to be angled for this I think)
- hole at the top of the pig tail or removing it

You have pretty Names for my Works... Pig Tail .
Yummyrum sayed its a Bastard

[der wo]

Ok "Wo", even German members don't know if I am wo or der or der wo...

I'll try the following things first:

- hole in the liebig nearby the valve (the tube has to be angled for this I think)
- hole at the top of the pig tail or removing it

Don't forget, you will need to have the liebig angled!
You have pretty Names for my Works... Pig Tail . This seems to be a special problem with Germans here. Look at the comments about my still http://homedistiller.org/forum/viewtopi ... 27&t=56682
Yummyrum sayed its a Bastard I am sorry, but he said, you are the bastard, not your still.

[still_stirrin]

...it gives air another easy entrance and exit, the air doesn't have to get pushed through the whole liebig. The distillate will be able to flow faster through the liebig. Perhaps this is enough to fix it.

I think you're on to something here, der wo. Since the liquid outlet (from the valve and plates) is lower than the liquid level in the plates, it will "pull" a suction when the valve is opened. The liquid return line to the column is larger than the opening of the valve, so the liquid will tend to flow into the return more likely than down the long path of the Liebig.

As the condensate "tries" to flow down the Liebig tube, it needs an air relief vent to break the partial vacuum pulled as the liquid flows. Currently, air must suck up through the Liebig to relieve that partial vacuum, and that trades a steady liquid flow down the Liebig's liquid tube for the pulsing flow of liquid and relief air suction.

If the Liebig's liquid (condensate) line had a larger bore, perhaps even as large as the liquid takeoff from the plates, then the competition for flow crossectional area may not be so compromised. But angling the Liebig from vertical may also help solve this as well.

And, if you can get a pressure relief vent above the Liebig such that it doesn't try to flow condensate, then that solution might also solve the stability of liquid flow dilema.

This place is great...where experience and innovation join to solve problems. Perhaps we can solve "world hunger"...or thirst similarly.
ss

[der wo]

The liquid return line to the column is larger than the opening of the valve, so the liquid will tend to flow into the return more likely than down the long path of the Liebig. Only if the return was vertical too. But it's horizontal here. As long there is no sucking from the side, all the distillate will flow down to the valve.

As the condensate "tries" to flow down the Liebig tube, it needs an air relief vent to break the partial vacuum pulled as the liquid flows. Currently, air must suck up through the Liebig to relieve that partial vacuum, and that trades a steady liquid flow down the Liebig's liquid tube for the pulsing flow of liquid and relief air suction.

If the Liebig's liquid (condensate) line had a larger bore, perhaps even as large as the liquid takeoff from the plates, then the competition for flow crossectional area may not be so compromised. But a needle valve with such a large bore diameter would not allow to control the product as fine as we want. But angling the Liebig from vertical may also help solve this as well. I want him to angle the liebig mainly that no distillate will drip out the hole.

And, if you can get a pressure relief vent above the Liebig such that it doesn't try to flow condensate, then that solution might also solve the stability of liquid flow dilema.

This place is great...where experience and innovation join to solve problems. Perhaps we can solve "world hunger"...or thirst similarly.
ss Ah no, this is boring. I currently play with a valve, a few copper tubes and fittings and hot glue in my bathtub to find out more details about this issues of LMs. Much more fun than saving the wales or something.

[Yummyrum]

Yummyrum sayed its a Bastard I am sorry, but he said, you are the bastard, not your still.

Don't listen to him 00Speedy , he is trying to use your insecurities in English compehension to get me in trouble
But you are right , that still is a Bastard

If you drill a hole in the top of the vertical Liebig you can solder a quarter of a pig tail over the hole facing up so no liquid falls out

[thecroweater]

OK you had me confused with hole in the liebig, you are meaning a vent at the valve I guess in which case that return for sure has to go. Makes me wonder why the liebig at all if its to run in pot mode forget the vent. My old reflux still had a vent straight after the take off valve
http://homedistiller.org/forum/viewtopi ... 6#p7017750

[still_stirrin]

Ah no, this is boring. I currently play with a valve, a few copper tubes and fittings and hot glue in my bathtub to find out more details about this issues of LMs. Much more fun than saving the wales or something.

HaHa der wo....you're a comedian.
Prost.

[der wo]

OK you had me confused with hole in the liebig, you are meaning a vent at the valve I guess in which case that return for sure has to go. Makes me wonder why the liebig at all if its to run in pot mode forget the vent. My old reflux still had a vent straight after the take off valve
http://homedistiller.org/forum/viewtopi ... 6#p7017750

Long time since I stumbled randomly to this thread. But now saw for the first time, that on the picture is a "sulfide gas venting hole" just where Pintoshine has the hole/vent at his LM path against siphoning. Do you have a link with the theory of this sulfide vent? Did you once try out, what happens when you block this vent (other than a burn blister on your thump)?

[Pikey]

The liquid return line to the column is larger than the opening of the valve, so the liquid will tend to flow into the return more likely than down the long path of the Liebig. Only if the return was vertical too. But it's horizontal here. As long there is no sucking from the side, all the distillate will flow down to the valve.

Agreed - I think the pressure would be positive from the column, but what is to stop the rising gasses from entering the tube and creating a back pressure against the condensate flowing down ? Possibly even re-evaporating the condensate in the normal reflux way ? and leaving through the hole at the slant plate, where the pressure would likely be less ?

[der wo]

You can see in his videos the reflux out the return starting and stopping again and again. Probably because the distillate at the pig tail is flushed back and forth and back and forth. And of course when there is somewhere space not filled with distillate, it will be filled with vapor. Creating a vacuum is not possible with such a apparatus like a boka. At a moment when the distillate at the pig tail flows in direction to the column, it sucks vapor (or perhaps in some cases air from the liebig) from the Tee in direction to the pig tail. Perhaps this flushes also distillate into the pigtail and then back into the column. -> not 100% potstill mode.
The pig tail hinders vapor from the column entering the return. But honestly I don't know, why it is so badly if a bit vapor enters it this way. The vapor would be there 3 sec later anyway (via reflux condenser, slanted plates, product tube).
Those are my two arguments against the pig tail:
- it establishes "huffing" in the system.
- I don't know any benefit it has.

[Yummyrum]

I agree that the pigtail is not the right type of fluid lock for the job .
My LM / VM has an external reflux tube but instead of a pigtail I have a 3/4" end cap similar to what the Plated stills use on downcomers.
It works fine.

I agree also that siphoning in that small pigtail is possibly contributing to the erratic reflux flow .....before cutting it off and sticking on a cup , you could try putting a hole at the top of the loop .......Think der wo suggested this early in the piece

[der wo]

Great pics and great still yummyrum.

Whats the diameter of the tubes?
Is there any siphoning visible? Either at the return when valve is closed or at the product tube, when the valve is full open?
2" or 3"?
Wattage?

[Yummyrum]

Thanks der wo
2" column
3/8" return line
2200 -2400 watts
Absolutely no sign of siphoning . The reflux pours off smooth as a babies bum .
Never stripped with it though .... always used my pot for that

[der wo]

The cap on the return, is it a modification? Did you ever run it without?
I want to know, if it is really beneficial also in practice.