Question Regarding 3'' VM Output

[Uisge_a_Ghlinne]

Good day, I have a question for the learned heads that occupy this forum.

I have built a stainless 3'' VM, height from barrel to bottom of take off 190cm, height from top of take off 30cm. Connection to barrel is a 3 to 2'' reducer connected by triclover clamps. Packing is stainless steel wool with two reflux centring collars; one one third up from bottom, one about two thirds up. The take off is a 2'' equal tee,with the pipe above also two inch. The takeoff reduces from 2'' to 1'', goes into a 1'' ball valve and reduces to 15mm after a 90 degree bend. Heating is by gas, the burner is rated at 33.000 BTU.

I have ran this beast twice, both times producing 95% without problem. However, no matter what I tried I could only produce at 2Lt an hour. My question; am I being unrealistic to expect more from this beast and if she is capable, what am I doing wrong?

[rubber duck]

2l per hour would be about right for a 3" VM the way you have it set up. You could get better speed with some centering rings, Maybe you could get 2.5l. some vapor turbulence at the take off T could help also.

If you want to go fast look into ARC, pretty interesting stuff but it's a little over my head.

[Uisge_a_Ghlinne]

A quick update on this question. Having tinkered with centring rings and restrictions before the reflux condenser with varying results, I have now managed to achieve 4.74Lt an hour from a 26Lt wash at 40%. This was achieved by fitting a restriction collar of approximately 20mm five cm above the top of the takeoff. I am absolutely delighted with the result.

So, now maybe a flute

[Samohon]

I added 2 centering rings to my 2" VM a few months back, one above the branch and one further down in the packing, it gave me another 550ml per hour and I was well chuffed...
Drastically reduced those 8 - 9 hour runs...
Thats great output from your 3" mate, are you still hitting +90% on the take off..?

As for the flute: Go on, you know you want to...

[aqua vitae]

A quick update on this question. Having tinkered with centring rings and restrictions before the reflux condenser with varying results, I have now managed to achieve 4.74Lt an hour from a 26Lt wash at 40%. This was achieved by fitting a restriction collar of approximately 20mm five cm above the top of the takeoff. I am absolutely delighted with the result.

So, now maybe a flute

I'd say lets go forward from here not backwards ( ), next step would be Automatic Reflux Control
But that's for neutral only.

[Uisge_a_Ghlinne]

Ah, this game is all about choice and beauty. OD, the product is at 95%. I could probably drive her a little harder but she was starting to growl.
The flute is on.Stainless due to cost of the 4'' pipe. One of the first threads I read on this forum threatened that once you built one you would not stop; how true.

[astronomical]

A quick update on this question. Having tinkered with centring rings and restrictions before the reflux condenser with varying results, I have now managed to achieve 4.74Lt an hour from a 26Lt wash at 40%. This was achieved by fitting a restriction collar of approximately 20mm five cm above the top of the takeoff. I am absolutely delighted with the result.

So, now maybe a flute

Has anyone else tried adding restriction above your takeoff port?

He said he went from 2l/h to 4.7l/h @ 95%.... Thoughts? Does anyone else get close to 5L an hour at 95% off a 3" VM.

He states it again in another thread

" I started playing around with centring rings to try and improve output. A centring ring below takeoff (any distance from 2cm to 10cm) made no real difference. Takeoff was slightly up at just over 2lt an hour. The centring rings at one third and two thirds down the column appeared to make no difference. However, when I added a centring ring with a 30mm orifice 5cm above takeoff my output rose to just under 3 litres an hour. With a tightening of the orifice to 25mm I am now pulling over 3 liters an hour at 95%. I need to do another few runs just to validate the quantities, however, the initial conclusion is that a further restriction above takeoff has a marked affect on take off quantity without affecting quality."

I'm all ears. I'm not doubting him, I'm just excited to try this and I wonder if it would work it my restricted LMVM setup.