Vapour management still plan

[Hari]

a VM does generally stop production ( pending efficiency % varies ) which is one off their strengths, - Yes I agree, however when the boiler vapour temp is 80C, ie wash has alcohol in it, there is no reason for product rate to stop or take off.

Could your column be flooding - liquid climbs to VM branch then syphon down condenser increasing flow ??

I doubt it- have spent some time and over 40 runs per year varying power levels etc.

How tight is the packing. ? Last year I removed all the ss packing as it was compacted and holding pressure in the boiler. (not good) . I removed half the packing and found that efficiency was slightly reduced.
During the last run I can obtain 95% @ 20C at 300-330 mL per hour.

Back to your initial comment regarding the horizontal length ie 3x the column diameter, ie 6 inches or 150mm. Mine is 4.5x ie 9 inches.

[Meatheadinc]

the problems you describe shouldn't be related to the horizontal length - that length should operate fine

PM answered

[Hari]

Thanks Meatheadinc, I am now proposing a visit to see Mac to purchase copper packing instead of the SS pot scrubbers, at least then I will have a consistently packed column.

regarding power, I have a 3000 W element and a Sutronics controller. I dont have a way of measuring the power level, however I can measure the amount of output at WOT (wide open throttle).

[Hari]

I purchasing the copper packing, cleaning it and running some heads through the packed column to ensure cleanliness. As my mass of packing went from 300g to 750g, the reaction time is slower understandably.

I had a copper cone placed just under the reflux condenser (RC) to direct reflux back to the centre of the packing. This I removed due to forum advise.

Set up the boiler with 40% spirit and after pre heat 3000W, backed off the power to obtain about 12mL per minute reflux and let reflux all night. Then removed heads and then ran it at wide open throttle (WOT) with 60mL / min column rate.
To explain, with my Sutronics controller, I have set three positions. Lets call them low, medium and high. To give me 12,30 and 60ml/min rate, I stopped off the RC and ran at WOT. These were the collection rates.
I then replaced the RC and ran again at WOT on high position, ie 60mL/min. The output was 15mL/min.
What is the reflux ratio? is it 4:1, ie 60/15? I thought it was the area ratio of column area versus valve area, which in my case is 14:1.

I let the still run for another hour and when I came back the output rate was nearly zero, even though the boiler temperature was still 80C with plenty of alcohol.
A quick suck on the outlet hose dramatically increased the output and after 15min was running at 15mL/min.

Any suggestions why this happens?
regards
Hari.

[MacStill]

Have you got the packing about 50mm below your take off arm ?

I could probably call up on saturday arvo and check things over for you, it'd be great to catch up for a chat anyway :handgestures-thumbupleft:

Cheers,

Mac.

[Hari]

Mac,
Packing is about 100mm below outlet. see picture from Mon Jan 26, 2015 6:37 pm. Packing is up to the bottom joint.

Saturday afternoon would be fine. My peak of cellar door visitors is usually at 3pm, but after 4pm is quieter. OK.
Hari.

[MacStill]

Mac,
Packing is about 100mm below outlet. see picture from Mon Jan 26, 2015 6:37 pm. Packing is up to the bottom joint.

Saturday afternoon would be fine. My peak of cellar door visitors is usually at 3pm, but after 4pm is quieter. OK.
Hari.

We dont close our shop until 2.30 on saturday anyway so 4pm would be fine, or I could call up during the week if that suits better, I have to go out to Midland in the next couple of days anyway so let me know if that suits better.

We could probably take this to private message so as not to clutter the thread any further too, but I'm sure If I can see the still I'll be able to nut it out for you :handgestures-thumbupleft:

Cheers,

Mac.

[Geeps]

I purchasing the copper packing, cleaning it and running some heads through the packed column to ensure cleanliness. As my mass of packing went from 300g to 750g, the reaction time is slower understandably.

I had a copper cone placed just under the reflux condenser (RC) to direct reflux back to the centre of the packing. This I removed due to forum advise.

Set up the boiler with 40% spirit and after pre heat 3000W, backed off the power to obtain about 12mL per minute reflux and let reflux all night. Then removed heads and then ran it at wide open throttle (WOT) with 60mL / min column rate.
To explain, with my Sutronics controller, I have set three positions. Lets call them low, medium and high. To give me 12,30 and 60ml/min rate, I stopped off the RC and ran at WOT. These were the collection rates.
I then replaced the RC and ran again at WOT on high position, ie 60mL/min. The output was 15mL/min.
What is the reflux ratio? is it 4:1, ie 60/15? I thought it was the area ratio of column area versus valve area, which in my case is 14:1.

I let the still run for another hour and when I came back the output rate was nearly zero, even though the boiler temperature was still 80C with plenty of alcohol.
A quick suck on the outlet hose dramatically increased the output and after 15min was running at 15mL/min.

Any suggestions why this happens?
regards
Hari.

:naughty: :naughty:

[Hari]

Hi All, I spoke to Mac.
He suggested I remove the 6mm tube from the end of the PC and replace it with a funnel to let the PC "breath"; answer, no more syphoning.

Thanks Mac.

[Hari]

Further developments.
I purchased some copper packing to give a constant density of column packing. I cut 900mm strips and rolled them to fit inside the 2" column tube. There were 16 of them and they weighed 50-52g each. Yes I could blow through the column.

I visited Mac; he could not find any reason why I was only getting 92-93% on the 1.6m column.

Yesterday I removed 10 pieces of packing and replaced then with 200g of stainless scrubbers, filling a metre of column.
The percentage increased with the maximum obtained of 94.9% at a low rate of 200mL per hour.

Today I will try with gate valve open further.

Has anyone experimented with the amount of copper packing in a 2" column? If you are getting 95+% at 1L per hour, what length of copper mesh do you have per roll?
Any suggestion are warmly welcomed.
Hari.