Distillation
When a liquid is heated
Its molecules react,
In fact they start to move around
And violently interact
Crashing into molecules
Which are not yet in motion
Until they gain such insane speeds
They break free of their potion
And so they make their great escape
In the form of vapor
Until they meet with something cold
And their adventure tapers
Losing kinetic energy
They start to coalesce
And become little liquid drops
Upon the cold surface
The process is not that unlike
A kettle boiling fast
The steam escapes the angry jug
And collects upon the glass
It also happens naturally
When the sun’s hot rays
Makes water to evaporate
Creating clouds of rain
In chemical technology
The procedure is done
With distilling apparatus
Or distillation column
Its purpose is to separate
Liquids that can steam
From ones that can’t evaporate
Or turn to gas it seems
The portion which evaporates
When heat is applied
Condenses as the distillate
Then comes out the other side
And the fluid left behind
The useless lump of goo
Has the honour of being called
The distillation residue…
The process of distilment is
Of very great import
For purifying substances
Of the volatile sort
And has been so for many years
Thousands so I’m told
The knowledge of its origin
Lost in days of old!
But how the practice has evolved
From then up to today!
The apparatus that is used
Varies in lots of ways
For example industry
Using chemicals
Requires such efficiency
The columns used are very tall
In fact in such an industry
The distillation columns
Can exceed 300 feet
From the top to bottom!
And so the apparatus can
Distill the mix inside
These columns oh so very tall
Can be up to sixteen feet wide!
Employed for making useful things
Like in the production
Of gases, fuels and oils
And of course petroleum
But of all the obvious
Distillation roles
Is the manufacturing
Of what we now call alcohol!
However it is limited
To the separation
Of substances whose boiling points
Differ in variation
Of at least zero point five
And to one degrees,
Celsius not Fahrenheit,
To distill with ease
Unless there is an additive
That can facilitate
The process for such substances
Outside the norm or common state
A process therefore that is called
By the designation,
When an additive is used,
“Extractive distillation”!
According to the principle
That is called Rault’s Law
Part of that which has the higher
Boiling point indeed will more
Or less be intermingled with
The vapor of the other
Of the lesser boiling point
So you will discover
That the latter substance will
Always have in it
Part of the other substance
Now contaminating it!
One way though to rectify
This unwelcome pollution
Is to take the distillate,
And try for a solution,
To return it once again
To the column’s start
And distill it yet again
To thin out the unwanted parts…
Every plant for distilling
Comprises of such things
As a source of heat of course
Essential for distilling!
And for the separation of
Volatile mixtures
A fractionating unit is
A necessary fixture
So that a distillation
Equilibrium
Is achieved depending on
The mixture’s composition
And when the distilling’s done
The final distillate
Is placed inside a cooler to
Cool down in its new state…
By Kerin Gedge
Copyright 2014
Based loosely on How Things Work: The Universal Encyclopedia of Machines, by Granada Publishing Limited, 1974 Edition
Click Below for
Words that begin with...
