Why You Can't Control Temperature

[Acrylic]

I understand what you meant now of course... overdriving the heat just as you explained which would make a mess of everything - being in a hurry etc. Thanks for clarifying for me much appreciated. It is a little intimidating with the equipment especially a home built rig and the learning curve is really deep.

[cayars]

Again sorry about that. It's really good you're reading a lot, learning and asking question when things don't make sense!

[Swedish Pride]

Man, i just caught this thread. So glad i didn't see this when I got going in this lark. Confusing as shit now, never mind if i didn't know my arse from elbow

[NZChris]

Man, i just caught this thread. So glad i didn't see this when I got going in this lark. Confusing as shit now, never mind if i didn't know my arse from elbow

The moderators could do newbies a favour by deleting the thread.

[Acrylic]

My two cents for what it's worth. As a newbie I've learned from this thread, including the dangers of falling into rabbit holes. I swore up and down I wasn't installing a thermometer on the still and I was going to learn this the way it's taught. So far so good! I am going to get good at this. I realize the finer points of all the chemistry and heat reactions may escape guys like me that aren't that clued in, however, I can appreciate that I can fully relate to what works in actual practice. Plus, there is absolutely nobody in my circles that is involved in anything like this. I agree this is a complicated thread, but it is also great reading for this newbie.
Just sayin
Thx

[cayars]

I just wish the title was different since temperature can obviously be controlled.

[Kareltje]

I just wish the title was different since temperature can obviously be controlled.

Of course: below boiling point by adding little or no heat, above boiling point by adding pressure.
But that is not what home distillers can easily do.

[cayars]

You add "pressure" to your still?
I manage heat (energy) to adjust temperature and vapor pressure.

[Swedish Pride]

you manage energy input, you get what ever heat that you get based on the mixture of the boiler at that point in time.

[cayars]

Well I technically manage heat (energy input) on the stove. The heat is there regardless if a boiler is sitting on it or not.
If you don't think the heat is there, I'd challenge you to hold your hand there for a bit.

If you change the word "heat" in your post to "temperature" then I'd agree with you, but it's only half the story as heat input (energy) also controls the amount of vapor produced.

[Acrylic]

Yes, however Swedish Pride explains it the way this newbie can understand it. All things being equal, the simplest answer is usually correct. Understanding everything written in this thread will never happen from my background. However, by applying a simple concept of heat to a boiler, managing cuts, and using some serious sense and awareness, an acceptable spirit can be produced. I don't have the education to grasp everything explained here, however I appreciate the higher concepts are presented. Cheers everyone!

[cayars]

As long as you understand it, that's all that matters.

[jonnys_spirit]

To be a little more specific we should use the term power - not energy - referring to the amount of power applied to the boiler. Whether it’s an electrical fired boiler where the power is measured in watts or a gas fired boiler where the power is measured in btu’s. “Energy” is not the correct term. Power is the correct term.

A fixed amount of alcohol(s) at a fixed resting temp (in a low wines solution ~ 60-80pf) will take a fixed amount of power to vaporize over a period of time. More power = less time and more smearing of the fractions. Less power = more time and less smearing of the fractions.

The temperature of the solution in the boiler (and the vapor produced) at any given point is a function of the compound being vaporized. More power does not raise the temperature. It just vaporizes the fractional alcohol compound quicker so that the next higher fraction can then vaporize once the previous fraction is gone and the temp then raises.

You can apply more power to vaporize the fractions quicker.

The underlying concept here is that the alcohol fractions present in the boiler control the temp of the liquid and the vapor while the power input controls the rate of vaporization and the amount of smearing of the fractions.

Cheers!
-jonny

[cayars]

Energy seems to be the correct term IMHO:

(some common definitions copied)
The British thermal unit (Btu or BTU) is a non-SI, traditional unit of heat; it is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.

In thermodynamics, heat means energy which is moved between two things when one of them is hotter than the other. ... That is, heat is defined as a spontaneous flow of energy (energy in transit) from one object to another, caused by a difference in temperature between two objects; so objects do not possess heat.

watt is the SI unit of power, equivalent to one joule per second, corresponding to the power in an electric circuit in which the potential difference is one volt and the current one ampere.

Joule is the SI unit of work or energy, equal to the work done by a force of one newton when its point of application moves one meter in the direction of action of the force, equivalent to one 3600th of a watt-hour.

[Acrylic]

Caught your post before leaving for work - thx for explaining the specifics - it resides in my collection of page snapshots for future reference - you've given me a bunch of stuff to mull over whilst I plow through the next ten hours
Cheers!

[jonnys_spirit]

Joules would be a measure of the amount of energy transferred into the liquid/copper/air. That complicates the understanding and discussion of what's happening unnecessarily with no real gain and no easy way to measure. Power is easily measurable and is a measure of the amount of energy applied to the boiler with a typical efficiency where we can assume a fairly typical energy transfer function from a gas fired boiler or an element fired copper or stainless steel boiler charged with a ~10%ABV wash/wort or 35%abv low wines.

More power into a fixed boiler load = Increased rate of vapor production.
Increased vapor volume from a fixed (steadily declining) load = more smearing of the fractional alcohols.

In any case, the amount of power applied doesn't control the temperature - Amount of power controls the rate at which the fractions are vaporized and thus the rate of temperature change over a period of time. The temperature at any given point in time is controlled by the makeup of the fractions in the boiler at that point in time.

KISS (and context) always applies unless there is a real need to increase complexity. We're talking about running a hobby still with water heater elements (1k25W up to say 5k5W) or a gas burner (10k-30k BTU) for probably 99% of the folks around here.

Cheers!
-jonny

[cayars]

Your trying to complicate a simple concept. Stop with your first 10 words "Joules would be a measure of the amount of energy"
BTU are also a measurement of heat/energy.

ENERGY being key to what is being measured.

People using gas, charcoal or wood don't add power (eg 4 more charcoal bricks of "power" or another 2 logs of "power") they add fuel used to create heat (energy).

Power is used to express methods or types such as electrical power, nuclear power, solar power, wind power or a time/rate measurement of work. You could say ENERGY is produced using mechanical power, electrical power, nuclear power, solar power, etc

[Saltbush Bill]

There is only one person who has turned an easily understood concept into a confusing and convoluted one Cayarse and that is you.
Anyone wishing to see a simpler and more easily understood version only need read the first post in the thread.

[Swedish Pride]

[Yummyrum]

The end