AN IMPROVED METHOD OF EVAPORATING LIQUIDS
Year: 1853

page_text: LETTERS PATENT to John Ambrose Coffey, of Providence Row,
Finsbury, in the County of Middlesex, Pharmaceutical Engineer,
for the Invention of "AN IMPROVED METHOD OF EVAPORATING
LIQUIDS."
Sealed the 9th June 1854, and dated the 14th December 1858.
PROVISIONAL SPECIFICATION left by the said John Ambrose
Coffey at the Office of the Commissioners of Patents, with his
Petition, on the 14th December 1853.
I, JOHN AMBROSE COFFEY, do hereby declare the nature of the said
Invention for "AN IMPROVED METHOD OF EVAPORATING LIQUIDS" to be as
follows, viz:-
My Invention consists in causing atmospheric air or other gases
to pass through the liquid to be evaporated, the air or gas used being
in such a state when introduced into the liquid that the vapour of the
liquid shall become diffused into it, and thus be carried off' or eva-
porated.
Thus I put the liquid to be operated upon into a vessel, and force

page_text: the air or other gases through it by an air pump or any equivalent
mechanical means.
If the air or gases be in a sufficiently dry state when introduced
into the liquid, the evaporation may be effected at the common tem-
perature of the atmosphere; but in order to ensure more rapid
evaporation, the air or gases or the liquid, or both, should be kept at
a more or less elevated temperature. The evaporation may also be
promoted by depriving the air or gases of hygrometric water before
passing them into the liquid, and this may be done by bringing them
into contact with chloride of calcium or oil of vitriol, or other sub-
stance having a powerful affinity for water. It is sometimes found
desirable to avoid bringing free oxygen into contact with the liquid to
be evaporated, in which case some gas may be used which does not
contain free oxygen, such for instance as atmospheric air, the oxygen
of which has been made to combine with carbon by bringing it into
contact with ignited charcoal.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Ambrose Coffey in the Great Seal Patent
Office on the 14th June 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
JOHN AMBROSE COFFEY, of Providence Row, Finsbury, in the County
of Middlesex, Pharmaceutical Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of December, in the
year of our Lord One thousand eight hundred and fifty-three, in the
seventeenth year of Her reign, did, for Herself, Her heirs and succes-
sors, give and grant unto me, the said John Ambroso Coffey, Ifer
special licence that I, the said John Ambrose Coffey, my executors,
administrators, and assigns, or such others as I, the said John
Ambrose Coffey, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might

page_text: make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Inven-
tion for "AN IMPROVED METHOD OF EVAPORATING LIQUIDS," upon the con-
dition (amongst others) that I, the said John Ambrose Coffey, by an
instrument in writing under my hand and seal, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and
immediately after the late of the said Letters Patent.
NOW KNOW YE, that the said John Ambrose Coffey, 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 :--
My Invention consists in causing atmospheric air or other gases to
pass through the liquid to be evaporated, the air or gas used being in
such a state, when introduced into the liquid, that the vapour of the
liquid shall become diffused into it, and thus be carried off. In order
to effect this object I put the liquid to be operated upon into a vessel,
which I call the evaporator, and which is represented at F in the
annexed Drawing, and I force air or other gases through it by a bellows
or air pump, or any equivalent mechanical means. The apparatus I
prefer to employ for thus forcing the air through the liquid I call the
blower; it is represented at C in the annexed Drawing. If the air
or gases be in a sufficiently dry state when introduced into the liquid,
the evaporation may be effected at the common temperature of the
atmosphere; but in order to produce more rapid evaporation, the air
or gases or the liquid, or both, should be heated before bringing them
into contact. The apparatus marked E in the Drawing, which I call
the calorifier, serves for raising the temperature of the air or gases.
It consists of a cylinder filled with steam, through which passes a
number of tubes conveying the air or gas from the blower to the
evaporater. The temperature of the evaporating liquid may be raised
by having a steam jacket attached to the evaporater, as shown at æ.
The evaporation may also be promoted by depriving the air or gases of
hygrometric water before passing them into the liquid, and this may

page_text: be done by bringing them into contact with chloride of calcium or oil
of vitriol, or other substance having a strong affinity for water. I
prefer to use oil of vitriol for this purpose, and apply it in a vessel A,
which I call the air desiccater. This vessel may be made of earthen-
ware or of lead. When the blower is in action, the air or gas enters
the desiccater by the tube 9, and through the perforated diaphragm
h, h, from whence it rises in bubbles through the oil of vitriol. The
desiccater is furnished with a liquor gauge k, to show the quantity of
liquid contained in it and a funnel and stop cock 1, for introducing
fresh acid. When the oil of vitriol has abstracted so much water
from the air or gas passing through it, that it ceases to produce the
desired effect, it should be replaced by fresh acid. The air passes
from the desiccater through the tube i into a vessel B, which I call the
air purifier. This vessel is filled with lumps of chalk, placed in such
a manner that the air passing between them and rubbing against
them, may be purified from any acid which it may have carried,
mechanically or otherwise, from the desiccater. In order to equalize
the compression of the air after it has passed from the blower, I find
it advantageous to employ an apparatus D, which I call the pressure
equalizer. This consists of an air-receiver made like a bellows, with
weights placed upon it so as to produce the amount of pressure re-
quired for forcing the air or gas through the liquid to be operated
upon, and having a valve which opens when this pressure is exceeded.
By means of this pressure-equalizer the air or gas is forced with a
uniform pressure through the tube m into the calorifier, and from
thence through the tubes n and o, to the bottom of the evaporater,
whero it passes through a perforated diaphragm p, p, and rises in bubbles
through the liquid to be evaporated.
It may sometimes be found desirable to avoid bringing free oxygen
into contact with the liquid to be evaporated, in which case some
gas may be used which does not contain free oxygen, such for instance
as atmospheric air, the oxygen of which has been made to combine
with carbon by bringing it into contact with ignited charcoal. An
apparatus of the same character and construction as the well-known
Joyco's stove, may be used for this purpose. The air after being in

page_text: contact with the ignited charcoal may be conveyed through tubes,
surrounded with cold air or water to cool it, and through a vessel
similar to the air desiccater, but containing a concentrated solution of
chloride of calcium in the place of oil of vitriol for the purpose of
washing the gas, and of arresting any particles of solid matter which
may have been carried from the charcoal fire.
I have herein-before described and fully explained certain means
by which I prefer to carry into effect my Invention of an Improved
Method of Evaporating Liquids, but I do not confine myself to the
employment of the exact means herein described, as these may be
varied without deviating from the nature of my Invention; what I
claim as my Invention being, the method of ovaporating liquids by
causing atmospheric air or other gases to pass through them, the air
or gas used being in such a state when introduced into the liquid, that
the vapour of the liquid shall become diffused into it, and thus be
carried off. But I do not claim the passing of streams of air through
hot saline solutions for the purpose of cooling the same, and causing
evaporation of water therefrom; this mode of operating for such
special purpose having been claimed by Mr. William Gossage in a
Patent dated the Fifteenth of June, One thousand eight hundred and
fifty-three, and the Specification of which was filed on the Fifteenth of
December, One thousand eight hundred and fifty-three.
In witness whereof, I, the said John Ambrose Coffey, have here-
unto set my hand and seal, this Fourteenth day of June, One
thousand eight hundred and fifty-four.
Signed and sealed in my presence,
F. W. CAMPIN,
Patent Agent,
JOHN A. COFFEY. (L.B.)
156, Strand.