IMPROVEMENTS IN EVAPORATING OR IN EXTRACTING MOISTURE FROM LIQUIDS, AND FROM SUBSTANCES IN A LIQUID
Year: 1858

page_text: LETTERS PATENT to James John Field, of Paddington, in the County of
Middlesex, Chemist, for the Invention of "IMPROVEMENTS IN EVAPORATING
OR IN EXTRACTING MOISTURE FROM LIQUIDS, AND FROM SUBSTANCES IN A LIQUID
Sealed the 5th November 1858, and dated the 7th May 1858.
PROVISIONAL SPECIFICATION left by the said James John Field at the
Office of the Commissioners of Patents, with his Petition, on the 7th
May 1858.
I, JAMES JOHN FIELD, of Paddington, in the County of Middlesex, Chemist,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
EVAPORATING OR IN EXTRACTING MOISTURE FROM LIQUIDS, AND FROM SUBSTANCES
IN A LIQUID STATE, AND IN APPARATUS TO BE EMPLOYED THEREIN," to be as
follows:-
My Invention consists in the employment for the purpose of evaporation of
gases or vapors of such nature as to prevent the oxidation of the matters
acted upon (where it is desirable to prevent oxidation therein), which gases or
vapors have been previously more or less perfectly dried. I either drive or
force such dried vapors or gases through the liquids or substances divided into
numerous small streams, or sheets, or jets; or I pass such dried vapors or
gases over the liquid or substance to be evaporated, whereby the gases will
carry off a portion of the moisture therefrom; I then cause the moist vapors

page_text: or gases to pass through or over sulphuric acid, or other chemical agent having
a great affinity for water or liquid, whereby they will be deprived of a part
of their moisture, and are thus rendered fit to be used as before; or they
may be passed into a drying chamber in addition to or in substitution for the
chemical drying.
My Invention also consists in subdividing the liquids to be deprived of
moisture into numerous small streams or jets, so as to expose a large surface
to the action of the vapor or gas employed to deprive them of their moisture.
The apparatus consists of a pipe leading from the chemical or mechanical
drying chamber into a series of pipes which conduct the dried gases or vapors
into a chamber, wherein the liquid or other substance to be operated upon,
divided into numerous small streams, sheets, or jets, by perforated spreaders,
or other like mechanical agents, is presented to their action. The gases or
vapors pass through another series of pipes into a second chamber containing
sulphuric acid or other chemical agent as aforesaid, or into a mechanical
drying chamber or apparatus, from whence they are conducted to be used over
again. After the substances fall in the liquid chamber I raise them by pump
or otherwise, to be again divided into small streams as before named. By
repeating this operation the substances acted upon may be reduced down to
any desired degree of fluidity. The process will be particularly applicable to
the obtaining of chemical extracts, and to the evaporation of sugar. Instead
of the pipes for the passage of the gases and vapors, the sides of the chambers
may be perforated, the object being to divide the gases or vapors into numerous
jets or streams.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James John Field in the Great Seal Patent Office, on the
6th November 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
JOHN FIELD, of Paddington, in the County of Middlesex, Chemist, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventh day of May, in the year of our Lord One
thousand eight hundred and fifty-eight, in the twenty-first year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
James John Field, Her special licence that I, the said James John Field,
my, executors, administrators, and assigns, or such others as I, the said James

page_text: John Field, 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 make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN EVAPORATING OR
IN EXTRACTING MOISTURE FROM LIQUIDS, AND FROM SUBSTANCES IN A LIQUID STATE,
AND IN APPARATUS TO BE EMPLOYED THEREIN," upon the condition (amongst
others) that I, the said James John Field, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands and seals,
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 date of the said Letters Patent.
NOW KNOW YE, that I, the said James John Field, 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 thereof, reference being had to the Drawings hereunto annexed, that
is to say:-
My Invention consists in the employment for the purpose of evaporation
of gases or vapours of such nature as to prevent the oxidation of the matters
acted upon (where it is desirable to prevent oxidation therein), which gases or
vapours have been previously more or less perfectly dried. I either drive or
force such dried vapours or gases through the liquids or substances, divided
into numerous small streams, or sheets, or jets; or I pass such dried vapours
or gases over the liquid or substance to be acted upon, whereby the gases.
or vapours carry off a portion of the moisture therefrom; I then cause the
moist vapours or gases to pass through or over chloride of calcium or other
chemical agent having a great affinity for water or liquid, whereby they are
deprived of their moisture and rendered fit to be used as before; or they
may be passed into a mechanical drying chamber in addition to or in substitu-
tion for the chemical drying.
My Invention also consists in subdividing the liquids to be deprived of
moisture into numerous small streams, or sheets, or jets, so as to expose a
larger surface to the action of the agent employed to deprive them of their
moisture.
The apparatus consists of a pipe leading from the chemical or mechanical
drying chamber into a reservoir, having one of its sides perforated with
numerous small holes or narrow slits, through which perforations the dried
gases or vapours pass into a chamber wherein the liquid or other substance.to

page_text: be operated upon (divided into numerous small streams, or sheets, or jets by
perforated spreaders or other like mechanical agents) is presented to their
action; the gases or vapours then pass through another series of perforations
into a chemical drying chamber, containing chloride of calcium or other
chemical agent, as aforesaid, or into a mechanical drying chamber or appa-
ratus, from whence they are conducted to be used over again. After the
fluids fall in the liquid chamber I raise them by pump or otherwise, to be
again divided into small streams, as before named, & so continue until the
desired degree of consistency has been attained.
The process is particularly applicable to the obtaining of pharmaceutical
extracts and to the evaporation of sugar, gelatine, and all substances liable to
detrimental change through heat or oxidation.
It will be seen that my method of evaporation secures in combination two
primary conditions, first, the employment of a low temperature; and, second,
the use of an atmosphere of such a nature as to be capable of. rapidly
abstracting moisture from the substances treated, without at the same time
inducing the oxidation of these substances, or, in fact, causing any change in
their constitution beyond that of partial or total desiccation.
I proceed to refer to the annexed Drawings, in order to shew the manner
in which my process (which I name the normal process on account of its
capability of furnishing medicinal and other products in an unchanged or
normal state) may be carried into effect.
Figure 1 is a side elevation of the apparatus I employ. A is a metal or
other vessel, the form of which I prefer to be that of an oblong or flattened
cylinder, so as to give a greater length from side to side than from front to s
back into the upper part of this cylinder a second vessel B fits air-tight, but
is easily removable whenever occasion requires. The bottom of this vessel is
perforated with numerous small holes, so as to divide any fluid flowing out
of it into small streams; it is connected at the upper part by means of a
pipe F with the pump or other agent used for supplying it with fluid; the
bottom of the cylinder A also communicates through another pipe F' with
the same pump, in order that any fluid falling through the perforated bottom
of the vessel B may be drawn (on reaching the bottom of the cylinder A)
through the pipe F, and again returned through the upper pipe F to the
vessel B; thus a circulation of fluid is constantly going on within the cylinder A
in the direction of its longer axis. C, C, are two reservoirs, securely attached
to each side of the cylinder A, communicating externally with the pipes G, G",
by means of a single orifice on each side, and communicating internally with
the cylinder A on each side through perforated plates or wire gauze, or

page_text: through the medium of a number of perforations made in the sides of the
cylinder A, as seen in the detached side view, Figure 2. The perforations are
limited to the areas covered by the reservoirs, and are designed to divide
the gases into numerous streams in the same way that the fluid in the vessel B
is divided. D, D, is a vessel containing a solid desiccating agent (this part
of the apparatus requires modification when a fluid desiccator is employed);
a tube descends from the bottom of this vessel to convey the water (abstracted
from the moist gases by the drying agent, as hereafter explained,) into a
graduated vessel H, by means of which the amount of fluid evaporated in and
withdrawn from the cylinder A may be correctly estimated. G¹ is a tube
leading from the desiccating vessel to a force pump; the exit valve of this
pump is in communication with the pipe G"; thus a second circulation is
established at right angles to the former, the one being a circulation of fluid
to be deprived of moisture, the other a circulation of gas or vapour to carry
off such moisture.
In order to set the apparatus in action the different parts have to be carefully
fitted together and all the joints air-tight. By means of two tubes fitted with
stop-cocks (not shewn in the Drawings) carbonic acid or some other gas fit
for the purpose is passed through the system of vessels until the atmospheric
air has been entirely expelled, the stop-cocks are then turned off, and the
vessel B is ready for its charge of fluid, which is pumped in through a feed
pipe K; the stop-cock K¹ on this pipe is then turned off, and the stop-cock f
being opened the fluid immediately begins-descending in a shower through
the perforated bottom of the vessel B; the pumps are then set in action,
whereupon a perpetual series of minute descending streams is established in
the cylinder A, which streams are traversed laterally by the continuous play
of the dried gases through the perforated sides of this cylinder; the gases thus
become saturated with moisture, of which they are deprived during their
passage through the vessel D, after which they are again pumped into the
cylinder as before, to transfer a fresh charge of moisture from the cylinder
into the vessel D, and so on.
A single supply of the gas becomes thus capable by repeated circulation of
depriving a solution of organic matter, however diluted, of nearly all its
moisture, the only limit being when the fluid becomes too thick to flow
Extracts may
or be forced through the perforated bottom of the vessel B.
thus be reduced to the consistency of molasses, in which state of concentration
they contain comparatively but a small per-centage of water. In those few
cases where absolute desiccation is required, even this may be effected, though
more slowly, by placing the cylinder A horizontally instead of vertically, and

page_text: continuing the operation as before, with the exception of using the fluid pump;
the back of the cylinder should in such case be hollowed out to prevent the
extract choking the perforations through which the gas passes. As the chloride
of calcium combines with the moisture of the gas passing over it, this sub-
stance liquefies and flows as a saturated solution into the graduated vessel H;
it thus becomes an index (without taking the apparatus to pieces) of the
degree to which the operation has been carried, and furnishes the necessary
data as to the time of its completion.
And having now described the nature of my said Invention, and in what
manner the same may be performed, I declare that I claim,-
First, the method herein-before described of evaporating or extracting
moisture from liquids and from substances in a liquid state, whether performed
in the apparatus shewn and described or in any other apparatus suited to the
operation.
And, second, I claim the particular arrangement and method of action of
the apparatus herein-before described, and represented in the Drawings
annexed, for the extracting of moisture from liquids and substances in a
liquid state.
In witness whereof, I, the said James John Field, have hereunto set my
hand and seal, this Third day of November, One thousand eight
hundred and fifty-eight.
JAMES JOHN FIELD. (L.S.)