Improvements in the Processes of Distillation and Rectification:
Year: 1886

page_text: Improvements in the Processes of Distillation and Rectification:
I JAMES WRIGHT of 84 Lombard Street in the City of London Civil Engineer,
do hereby declare the nature of my said invention and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement:―
Liquids and semi-liquids are subjected to the process of distillation and
rectification for the purpose of liberating and separating one or more of the most
desirable ingredients of the distillate from the others.
It is known that a certain amount of heat imparted to the distillate will induce
the vapourization of the special ingredient to take place, and in this state of
vapour it rises from the residue, and passing through the neck of the still into a
series of pipes, and the heat being again abstracted, it is recondensed and received
into a vessel or safe in the liquid state, the other ingredients of the distillate
remaining in the still are then drawn off into another vessel.
My invention relates particularly to the distillation and rectification of Spirits,
where the great object is to liberate and separate the vapourization of the Alcohol
or Alcoholic compounds from the other ingredients and impurities of the wash
within the still.
In all processes of distillation now practised; the vapourization and liberation of
the Alcohol is carried on in such a way, that the distillate is always subjected to the
external pressure of the atmosphere and the elastic force of the vapour in the still.
The effect of this pressure upon the distillate is such as to hinder the rapidity of
the distillation, and at the same time necessitates the application of a much greater
temperature to induce vapourization, but the most important objection to this
pressure, is that the temperature of the distillate can not be kept at a lower
temperature than the heating medium applied to produce vapourization, so that if
a certain steady fixed temperature is desired in the distillate, to vapourize a
special ingredient, it can only be done by regulating the heating medium to the
temperature necessary to vapourize the special ingredient required-This is much
too slow and unprofitable a process.
To obviate these, and to enable distillation to be carried on more rapidly and
effectively and at much reduced temperatures, I propose to create and maintain
within the distilling or rectifying apparatus, as complete a vacuum as can be
obtained by efficient air pumps, or other well known means in order to reduce
D

page_text: the external pressure upon the distillate during the process of distillation and
rectification. By.these means I am enabled to carry on the processes of distillation
and rectification at much lower temperatures than heretofore, and hence to much
more accurately adjust the exact amount of heat required to produce the desired
vapourization temperature and to maintain the temperature of the distillate at any
fixed point necessary to vapourize the special ingredient required, and to vapourize
all that ingredient pure, without mixing or contaminating it with any of the other
ingredients of the distillate-This is effected by my process without any accurate
regulation of the heating medium and although the heating medium be applied at
a temperature greatly in excess of the required vapourization temperature, the
temperature of the distillate will remain constant and steady until the required
ingredient is vapourized.
The requisite beat may be imparted to the still and to the distillate by any of
the ordinary methods-say by the direct action of incandescent heat on the
exterior of the Wash Boiler or Still. But as I require for inducing the requisite
vapourization a much lower temperature, owing to the existence of the partial
vacuum, I prefer for many reasons to make use of an enclosing steam or water
jacket round the exterior of the Still, and by an introduction of steam or hot
water I can raise the beat of the distillate up to the known vapourizing
temperature required, and maintain it steadily at that point until the special
ingredient is vapourized.
I propose also to make use of a coil or coils of steam pipe, introduced into the
interior of the still, so that I can use the jacket when needed alone, or the coil
when needed alone, or a combination of both, to induce the constant even
temperature of vapourization of the Alcohol.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what I
claim is :-
The use of a partial vacuum or reduced external pressure within the Still during
the process of distillation and rectification: and as resulting from the said vacuumi
during the said process I further claim
The process of distillation and rectification at much lower temperatures than
can now be effected and the important advantage of controlling and regulating the
temperature of the liquid to be distilled, and maintaining it at any desired fixed
point, and at the same time carrying on a rapid vapourization of the ingredient
required.