StillSmart

After 4 years of using my air still I finally had my first puke. it was massive. Emptied all of the still bar about 500ml. It occurred 1 hour into the run just as it was reaching temperature.

I was powering the head from a separate power lead which allowed the head to surf the surge all the way up (about 3 foot into the air). With it not being plugged into the base it had nothing to hold it down. This may be a blessing as most of the liquid was allowed to rise vertically whereas it may have been thrust horizontally when it hit the resistance of a tethered lid

I had the ceramic discs in but no conditioner or veg oil as it was a second run using a 30% mix.

It's left a bit of a mess, but nothing is damaged and nobody got hurt.

My main reason for posting is thus... I was sitting at my desk about 5 foot away. Had I been within 3 foot of the still I would have been collateral damage! Although most of it went directly upwards some sprayed outwards and landed a couple of feet from my position.

I've been doing my second run using a plug in dimmer switch to dial down the wattage to prevent runs. However I've been starting the boil at full wattage then dialling it down to 160 watts when it reaches temperature & starts dripping. This has been working fine until now. I think Ill start with it at 160 watts from now on.

as long as you're fine and no real damage the mess can always be cleaned up. did you add the conditioner and boil enhancers ?

I had boil enhancers in but no conditioner as it was a second run.

Yep no real harm done and all cleaned up now.

I think I'll get some copper boil enhancers and start using conditioner in my second runs.

Good news you are OK.

Although more dramatic than mine, I think this is similar to what I had.

l replaced the seal. It had got quite loose, but I hadn't noticed. Also went over to using 1p pieces in the bottom. They rattle really well. So far so good.

this happened to me when I was doing a spirit run with my airstill but luckly I spotted the top
trying to lift of from boiler. so now I use a strap and rachet from poundland

I had a similar thing happen but I had nothing in the still to prevent it (forgot to put in the copper bits and pieces of granite that I use). Do NOT NOT NOT toss them in if you ever forget this. Wait for it to cool or it will instantly surge boil. I was drunk after breathing in the fumes while cleaning up. Good thing there was no ignition source!

Chuck

Magnu420 wrote: ...so now I use a strap and rachet from poundland

IMO you are making a surge INTO A BOMB

If a surge is the only means of escape of energy - do not try to contain it - resolve the issue causing it. Please please please do not use a strap.

+ 1 what Mashy said. Using a strap is not good cause if pressure builds up, such as during a surge boil, the pressure will find a way out and if that means blowing the head apart the damage, and injuries, could be catastrophic, Not to mention the awkward questions from the local constabulary as to why all your windows suddenly blew out at the same time

Be safe out there

AM

Shall we get real here?
The air still may be the only still in common use on this forum that does NOT have its head routinely fixed down,most of us bolt our stills together,one way or another.
The air still also has possibly the smallest volume condenser.
Any surge that doesn't lift the lid will blow out through the spout.
It may indeed force the air still over.
Bomb?
I think not.

Robert.

Yes, unless the spout was plugged with something more resistant to moving than the metal top or side of the still. That seems unlikely.

Chuck

Chill. Agree unlikley.
However the diameter of the spout is not of a sufficient diameter top deal with the surge. Else we would never have had documented cases of this surge or puke in the first place.

Larger stills, used by some here, are open to the atmosphere through a 2"-6" wide riser and a column that usually extends 1 metre to 2 metres above the boiler. In addition, a surge boil in a 50 lt still will result in no more than a couple of litres bubbling up a wide column and being cooled and depleted as it rises with very little actually emerging through the condenser. In this size of still a surge boil does not have the power or pressure to spew the contents of the boiler into the local atmosphere.

The Airstill on the other hand, can, when a surge boil happens, chuck it's entire contents several feet into the air in a micro second, because the pressures are sufficient to do so and the resistance too little to prevent it.

The small internal opening, hardly 10mm wide, is the start of the Airstill's condenser. During a surge boil or puke, where 4 litres of heaving, bubbling liquid is trying to leave with great urgency this opening would probably be unable to handle the volume and velocity of liquid looking for a way out.

You can run an Airstill for years and never have a puke but when it happens it takes us all by surprise and can cause serious injury. In Makum101's post he said ".....I was sitting at my desk about 5 foot away. Had I been within 3 foot of the still I would have been collateral damage!" In fact, had he been checking his Airstill at the time the surge happened, we might be hearing about his horrific burn injuries on the TV.

Distilling is no place for complacency. It is a brilliant and fascinating hobby but don't forget what we're dealing with. If something dangerous is possible in your setup take reasonable steps to prevent it. Extreme solutions can produce extreme and unforeseen and sometimes catastrophic consequences - why take the chance when there are more reasonable solutions possible.

The proper approach to Surge Boiling is to prevent it in the first place.

Using boil enhancers is a no brainier, conditioner is also a must, on stripping runs in particular. However, even those steps only reduce the probability not the possibility.

The additional step that I know from experience reduces the probability of puking in an Airstill to a non consideration, is a clean and clear wash.

Getting the wash crystal clear is not a necessary step but it will, based on my long experience, effectively prevent puking and it takes very little to achieve.

AM

Thanks for all the advice.

Been out and bought some 'still spirits copper boil enhancers' (£8.99!) and a bag of new ceramic enhancers to replace my 4 year old ones. Two bottles of distillers conditioner. I've also checked that there is no blockage in the coil / spout - there wasn't. Going to do another spirit run over the weekend.

Oh and yes I did feel slightly tipsy while cleaning up, and that was with the windows open! lol.

Do I use the copper AND the ceramic boil enhancers together or just one or the other?

The shocking part is I've regularly been doing my stripping runs using a timer timed to commence at 4AM. Could have been nasty! I will always make sure I'm present from now on.

Prevent the cause rather than try and keep the lid on !
100% with AM on this
Might be a wee bit of kit but not to be messed with

There are two different things being spoken of here,a surge and a puke.
They may both force a boil over,but for different reasons.
It should be easy to cause a puke intentionally,much harder to cause a surge boil.
In fact,I wouldn't know how to try,apart from leaving out boil pieces,which should prevent it.
If I was not away from home for the next couple of weeks I may have been tempted to strap the Smartstill together,with a really dirty wash inside,place it outside and view the results.
I'll put on the ever growing list of things to do when I get back.

Robert.