advice please?

[devotus]

I've finally found 99.9% of what I need to build my vm and am basicall going off the design in the Compleat distiller, however I have a couple of questions...with pics.



This is basically a copy of the one in the Cd but with valves instead of blanking plates, the worry I have with this is the thermometer position: If it's directly under the reflux coil will it not get refluxed on and therefore be a bit skewed with readings?

IF so then what are your thoughts on something like this ....




both will be built with 42mm pipe at 1m-1m 20cm high, a single coil refux and a 20mm/13mm Liebig.

I am building with 42mm as 2" pipe and fittings are far too expensive for a column that I will be only using for 6-8 months. Also the small difference in diameter only effects the speed of operation and as I will only be using a 10 litre boiler it doesn't bother me that much..I think. :?

Any thoughts would be appreciated

[R-sole]

You need to loose the second valve in each design. The system should be designed so it's open to the atmosphere, otherwise it's a bomb.

You only need a valve on the product outlet.

Second design will work except there is no way to centre the reflux simply.
First design will work fine with the thermo sticking into the branch of the tee just before the valve...

Like this..

50mmsinglewound1.jpg

[devotus]

Thanks heaps 5Star, If the first design works without temp reading problems then I'll stick with that.

I put the second valve in as a control measure with one always open, eg when running in total reflux then the valve under the reflux coil is full open and the valve before the liebig full closed, when I reach equilibrium then open liebig valve a fraction and close reflux valve a fraction to try and achieve 90%/10% ratio. Is that incorrect thinking?

[devotus]

Maybe I should make that thinking a bit clearer,

I assume that the vapour would travel the path of least resistance therefore when the valve under the reflux coil is wide open (or non existent) then the vapour would travel preferentially in that direction. I continued assuming that even if I opened the valve before the liebig a fraction then the resistance from a tapering outlet would lead to the vapour still travelling up toward the reflux coil with an open end.

Also as a another thought path was that toward the end of the run I could shut the reflux coil valve completely and open the liebig valve full open and just for finish run it as a plain reflux still and direct all I can to my out take.

This is just my thinking and I'm not educated in physics so I'm probably not entirely correct.

[R-sole]

It's an accident waiting to happen as it's drawn. Even if you never fuck it up and forget to open one of the valves, you've already said it'll be sold to someone else who just may :?

Reflux ratio is controlled by the single valve, you don't need to fix something that works.