Parry water boiler

[Donnydarko]

Opinions on this Parry water boiler as a start to making a still, boils up water just fine but it's the shape of the lid and the inability to secure it down i have concerns about!

[NZChris]

It isn't copper.

It has a huge diameter to seal.

It has a plastic spigot.

Apart from that, it looks really good for something.

[rubelstrudel]

Try googling "Expanded PTFE" sealing band. You might find something that could be used to line the lid.

[NZChris]

Try googling "Expanded PTFE" sealing band. You might find something that could be used to line the lid.

Expanded PTFE has very little memory, so is unlikely to seal well on a lid that isn't permanently clamped.

[Yummyrum]

Also need to get bypass the thermostat and preferably add a power controller .

[Donnydarko]

Re thermostat, is it bad to have on/off temp control on boiler? 3kw heater, i understand being able to control the element temp would be good but what effect would current control have on the boil? I have a way of sealing the lid, just sorting some fittings for the column and condenser.

[NZChris]

It seems you have some common beginner assumptions about distillation. On/off heat control is not good for distilling and you can't control the temperature a wash boils at any more than you can control the temperature that water boils at.

[LWTCS]

Flower paste works just fine.

As for thermostatically controlling heat input,,,,not optimal,,at all.
Think of an actual live flame. The input is constant. Either a little flame or a big flame,,but always a flame.
No flame, no pressure to hold vapor in suspension and drive it toward your product condenser.

Every time thermostat cycles off, all of your vapor/product will stop flowing. That behavior will produce less than your best effort every single time.

Also, you can't control your kettle temperature as it is the quantity of alcohol in the kettle that determines the boiling point. Since you'll be rendering out the alcohol,,the boiling point will never remain the same. The liquid temps have no choice but to increase as the run progresses. That too is why thermostatically controlling your kettle will almost always leave alcohol in the kettle. You could just set your thermostat to "full blast". But then your quality of separation will suffer as well.

[MtRainier]

If you can really seal the lid like you say, then you could buy the heater controller kit from Still Dragon for a few dollars and install it to the middle of an extension cord after locking the thermostat on that boiler full on. The controller will regulate the current to it and as a result, the power.

[Donnydarko]

Thank you, i can control the power with a eurotherm controller we use at work and adjust the output to the element, i understand the boiling point of the liquid will change as the alcohol diminishes, i need to read up on the boiling process, and good tips or lonks for newbie reading. Still getting rig together at the moment. Thanks again all, much appreciated

[Donnydarko]

Links.....not lonks!

[still_stirrin]

... is it bad to have on/off temp control on boiler?

On-off control is great for emergencies...when you absolutely have to kill the power asap.

... i understand being able to control the element temp would be good

Controlling the element temperature is immaterial. Even a thermostatic control won’t manage the temperature of the element, only the cycling on and off of the heater.

...but what effect would current control have on the boil?

The heater element is a resistive element. Power through it and the corresponding heat it produces is proportional to the power consumed. And power is equal to the square of the current x the resistance (I x I x R = P). So, managing the current manages the power exponentially.

And since the boil rate in kg/s is a function of the heat input (power), you control the vapor production by heat input while the temperature will vary according to the constituents in the wash. As the boil progresses, the temperature of the boil will rise as the higher volatile components are liberated. The rate of vapor production, however will remain proportional to the heat input irrespective of the temperature of the boil.

This is “distilling 101” and if you don’t understand it, you should take some time to read more about it and the physics involved.
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[Donnydarko]

Thanks, could you point me to some reading material/links?

[still_stirrin]

Thanks, could you point me to some reading material/links?

A start: https://homedistiller.org/theory" onclick="window.open(this.href);return false;" rel="nofollow

[Bushman]

I use this for a gasket on my antique milk can boiler on my essential oil still.
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