What happens if.....

[Patching246]

Let's say, for hypothetical reasons, I left my takeoff valve partially open during heat up on a boka, allowing vapour to pour out for 4 mins before I spotted the problem. After a full hour of waiting, I still collected and discarded fores, but - aside from the fact I nearly killed myself - what is this mistake likely to do to my cuts?

Can I expect fewer heads/tails, or will it be the same as if I had reached equilibrium?

[Monkeyman88]

There would just be less heads. As the fores would already be gone. Just like in a pot still. The fores will still be the first stuff out.

[gemcutter]

During heat up you should have no vapor coming out of a boka...or any time after that if you have sufficient cooling of the vapor stream.....get a nice comfortable chair and some form of entertainment and SIT RIGHT BY YOUR STILL. Feel your column and keep feeling it as the vapor climbs the column......you can usually predict the first drops coming out of the collection tube with in ten seconds plus or minus and NEVER have vapor at all. If you do you either have insufficient cooling,and/or too much heat input.You want to concentrate heads and fores and to do so as the vapor climbs and heats the outside of the column you are getting reflux from you previously cool packing.once past the packing your thermometer should spike quickly from 70-90 degrees to 170 or so....you need to reduce the heat before it get to the thermometer to allow the vapor to rise gently within the column and then past the plates to your cooling coil.The water to your coil should have been on already ,long before any vapor hits it.....too much heat after you are getting vapor traveling up your column isn't good for two reasons...you lose the reflux from the cool packing and you risk puling into the packing if the boiler fills the column with liquid.Both of which reduce the effectiveness of the boka at eliminating heads and fores like they are designed to do.


If you don't understand what i'm saying shut down running this still and read for a few months.They weren't kidding.

[still_stirrin]

You just pushed the lighter volatiles through. However, without reflux compression there was a little goodness with the throw away. But no major problem other than the explosive vapor leak. Once identified and corrected, you set things back in order.

So obviously, don't intentionally run it like that next time. OK?
ss

[Patching246]

So obviously, don't intentionally run it like that next time. OK?
ss

Haha, no. It was an oversight and lesson learnt! I never let the still out of my sight - it was just I didn't notice it until the smell hit me. It was ultimately a really good run, I just collected less product than I was expecting and so was wondering/hoping that the hearts might start sooner. Currently resting so I will know soon enough...

Thanks