MENTS IN EVAPORATING CANE JUICE AND OTHER LIQUIDS, AND IN APPARATUS FOR THAT PURPOSE."
Year: 1852

page_text: LETTERS PATENT to John Aspinall, of King William Street,' in
the City of London, Engineer, for the Invention of "IMPROVE
MENTS IN EVAPORATING CANE JUICE AND OTHER LIQUIDS, AND IN
APPARATUS FOR THAT PURPOSE."
F
PROVISIONAL SPECIFICATION left by the said John Aspinall at the"
Office of the Commissioners of Patents, with his Petition, on the
1st October 1852.
1027
I, JOHN ASPINALL, do hereby declare the nature of the said Inven-
tion for: "IMPROVEMENTS-IN EVAPORATING CANE JUICE AND OTHER LIQUIDS,
AND IN APPARATUS FOR THAT PURPOSE," to be as follows: -
I evaporate cane juice and other liquids by placing them in a close
vessel, and partially exhausting the air from above the surface of the
liquid, and then admitting cold or heated air at the lower part of the
vessel. By this means the evaporation may be conducted at a low
temperature, so as not to injure the cane juice or other liquid, and
without the necessity of exposing the vessel to the direct action of
the fire.

page_text: The apparatus for this purpose may be made in various forms. One
arrangement consists of a cylindrical vessel of considerable depth, with
a perforated false bottom and a close top connected to an air pump. A
series of small vertical pipes are placed by the side of the vessel and
connected to a chamber which communicates with the lower part of
the vessel. The pipes and vessel are partially immersed in a pan, or
surrounded by a casing into which steam, hot water, or hot air are
introduced. When the air pump is put in motion air is drawn down
the small vertical pipes, and through the perforated false bottom,
whence it rises through the cane juice or other liquid contained in the
vessel. The air becomes warmed in its passage through the pipes, and
produces evaporation in passing through the warm liquid in the vessel.
The entrance of the air is regulated by valves. Various other forms of
apparatus on the same principle may be constructed.
Another of my improved apparatus consists of a pan in which two
rollers are partially immersed, and an endless band of wire gauze,
canvas, or other suitable material is passed round the two rollers.
The rollers being set in motion raise a portion of the liquid on the
band, which passes through a box or casing above the surface of the
liquid, where it is exposed to a current of warm or cold air, produced
by an air pump or fan or other suitable means. This apparatus may
either act under the pressure of the atmosphere or the pan may be
covered over and the air withdrawn by an air pump as fast as it enters,
and thus a partial vacuum may be maintained in the pan. The
evaporation may thus be conducted by warm air acting in a partial
vacuum, as in the first described apparatus. The pan may be heated
by a steam jacket or otherwise to accelerate the process. It is suffi-
cient for one roller to dip into the liquid, or for the band to bag down
between the rollers and dip into the liquid, without the rollers them-
selves being actually immersed. A scraper is fixed to remove any solid
sugar or other matter from the band.

page_text: SPECIFICATION in pursuance of the condition of the Letters Patent,
filed by the said John Aspinall in the Great Seal Patent Office,
on the 31st March 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
JOHN ASPINALL, of King William Street, in the City of London,
Engineer, sent greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of October, in the year of
our Lord One thousand eight hundred and fifty-two, in the sixteenth
year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said John Aspinall, Her special licence that I,
the said John Aspinall, my executors, administrators, and assigns, or
such others as I, the said John Aspinall, 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 CANE
JUICE AND OTHER LIQUIDS, AND IN APPARATUS FOR THAT PURPOSE, upon the
condition (amongst others) that I, the said John Aspinall, 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 date of the said Letters Patent.
NOW KNOW YE, that I, the said John Aspinall, do hereby declare
the nature of the 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 accompanying
Drawing, and to the letters and figures marked thereon, that is to say:
My Invention relates to certain improved modes and apparatus for
evaporating cane juice and other liquids at temperatures below the
boiling points of such liquids, as herein-after described.
Figure 1, of the Drawing is a plan; and Figure 2, is a vertical section

page_text: of one
of my improved apparatus. A, is a cylindrical vessel, placed
vertically, and having a perforated false bottom B, under which is a
chamber C. D, D, are a series of vertical tubes, connected at bottom
to the chamber C, and at top to another chamber E, on which is a
short pipe F, with a valve G. The whole of this apparatus is placed
in a pan H,. containing water or other fluid. The pan El, may be
covered over so as to form a jacket or casing round the apparatus.
The vessel A, is closed at. the top, and provided with a pipe I, which
conimunicates with an air pump or other exhausting apparatus.
In order to evaporate cane juice or other saccharine solution by this
apparatus the saccharine solution is introduced into the vessel A,
through the pipe F, or through a separate pipe or opening, until that
vessel and the tubes D, are partially filled by it. The pan H, is filled
with water and heated by a fire placed beneath it, or by blowing
steam into the water, or in any other convenient manner. Or, in lieu
of filling the pan or casing H, with water, it may have heated air
blown through it; but the temperature of such air is not to exceed
212 degrees of Fahrenheit's thermometer when operating upon cane
iuice or other saccharine solution. In whatever way it is heated,
therefore, the temperature of the heating medium is to be less than the
boiling point of the saccharine liquid to be evaporated, or less than is
sufficient to exercise an injurious: action upon the sugar. The air
pump is now set in 'niotion, and the air withdrawn from the upper part
of the vessel A.. Air then enters through the pipe F, valve G,
chamber E, tubes 'D, D, and chamber C," and passing through the
perforated bottom B, bubbles up through 'the saccharine solution" in
the vessel A: The air becomes warmed in its' passage through the
tubes D, D, and in passing through the saccharine solution it evapo-
rates and concentrates it. It is necessary that the vacuum in the
upper part of the vessel A, should be sufficient to cause the air to
overcome the pressure of the column of liquid in the vessel A, and
thus the evaporation is conducted in a partial vacuum.
The degree
of vacuum or diminution of pressure in the upper part of the
vessel A, may be increased by increasing the height of the column of
liquid in A, or by partially closing the valve G, so as to check or

page_text: .
throttle the ingress of the air. If the valve .be entirely closed the
ingress of the air. is stopped; and the evaporation proceeds as in the
ordinary vacuum pan. If the vessel A, be made sufficiently high to:
obtain the requisite vacuum by the column of liquid, the valve G
pipe F, and box E, may be dispensed with. On the other hand, if the.
vessel A, be shallow, the requisite vacuum may always be 'obtained by
the employment of the valve G, as first described. This may be a slidė;
valve or other valve adjusted by hand, or it may be made like the safety.
valve of a steam boiler, opening inwards, and loaded with a spring or
weight proportioned to the degree of vacuum required. The form of this
apparatus admits of some variation. Thus, the vessel A, may be made
square, or oblong, or spherical, or of any other form which may be found
convenient, and the tubes D, D, may be placed all round the vessel A,:
instead of at one side, or they may be carried horizontally through the
side of the casing H, in lieu of being placed in a vertical position..
The casing H, is filled with water, and being open to the atmosphere
the temperature of the water cannot rise above its boiling point, and it
is to be kept as much lower as may be found necessary, to prevent:
injury to the cane juice or other saccharine solution which is. being
evaporated. In lieu of the series of small tubes D, D, 'a single pipe
may be employed, and the air will then enter the chamber C, in a cold:
or nearly cold state, and the evaporation will consequently proceed.
with less rapidity than when the tubes D, D, are employed for warming
the air. It will, however, still be conducted in a partial vacuum,
with the assistance of air, and without bringing the saccharine solution
into contact with any surface or substance at a temperature so high
as that at which it boils under the pressure of the atmosphere.
Another of my improved evaporating apparatus is shewn in sec-
tion in Figure 3. A, and B, are two rollers, which are partially
immersed in cane juice or other liquid contained in a pan or vessel C.
which may or may not be inclosed in a casing or jacket for the pur-
pose of heating it. D, is an endless band of canvass, or Russia
duck, or wire gauze, or other suitable material, which is passed round
the two rollers A, and B, which revolve in the direction shewn by
the arrows. The pan is inclosed at the top, and a current of warm

page_text: air is introduced at the pipe E, and escapes at the pipe F, or it may
enter at F, and escape at E. The liquid is raised by the band D,
and evaporated by the current of warm air in passing from A, to B.
It is not necessary that the rollers should be immersed in the liquid,
as the band may be allowed to bag down between them, and so come
in contact with it. G, is a partition which separates the pan C, from
the compartment K. H, is a scraper which is fixed on the partition by
means of a hinge or joint, which allows it to rest against the band.
This, scraper removes the sugar and concentrated solution from the
upper surface of the band, and directs it into the compartment K. I, is
another scraper or bar which may be placed across the band for
scraping its under side; and L, is a gutter or trough for receiving the
scrapings, which are conveyed by it into the compartment K. i, is a
similar scraper which may be placed above the band in lieu of the
scraper H; and 7, is a gutter which receives the scrapings which are
pushed over the edges of the band by the scraper i, and conveys them to
tlic compartment K. The solution is evaporated or concentrated during
its passage from A, to B, and delivered by the scraper or scrapers into
the compartment K. A fresh portion of solution may be introduced
from time to time, or continuously, into the pan C, and in like manner
the concentrated solution may be drawn off from time to time from the
When a
compartment K, or allowed to flow out as fast as it enters.
quantity of solution has been thus concentrated, it may be again treated
in a similar manner in the same apparatus, or in another similar
apparatus, to concentrate it still further, or a series of these apparatus
may be arranged in succession, so that the solution may be gradually
concentrated and evaporated as it proceeds. Or a single band may be
used, as above described, and it may be made of sufficient length, or
its motion may be so slow that the solution may be concentrated to
the requisite degree by once passing along the band. An apparatus of
this construction would, liowever, occupy a considerable space, and
tlicrefore the arrangement shewn in Figures 4, and 5, may be found
preferable. Figure 4, is a side view, with the side of the casing
removed; and Figure 5, is a plan, with the top removed. In this
arrangement the endless bands D1, D2, D3, D4, D5, D6, and D', are

page_text: placed vertically instead of horizontally, and only one roller of each pair
is immersed in the liquid. A¹, to A, are the upper rollers, which are all
driven in the same direction, and cach of which is adapted for receiving
two bands D', to D, and d', to d, placed side by side. One end of
the spindle of each roller is carried through the side of the casing,
and a toothed wheel is fixed upon it. These toothed wheels do not
gear into one another, but into intermediate toothed wheels placed
between them, so that when motion is given to one of the rollers the
others all revolve in the same direction. Or the rollers may be driven
by bevil wheels or bands or other suitable means. The spindles of the
rollers are provided with stuffing boxes where they pass through the
side of the case M. These stuffing boxes are, however, not required
when the apparatus is employed under the ordinary pressure of the
atmosphere. B', to B', are the lower rollers, which correspond to the
upper ones, and whose spindles enter vertical grooves, by which they
are guided, although free to move up and down. The weight of the
lower rollers keeps the bands D', to D', extended. Each of the lower
rollers B', to B', works in a pan or trough C', to C', and each trough.
is furnished with a lip or scraper I', to H', for scraping off from the
bands the concentrated solution or solid matter, which falls into the.
next trough. The solution to be evaporated is introduced through the.
pipes P, P, and the perforated branch pipes p, p, by which it is thrown ;
in a shower upon the bands D', and d', or the solution may be allowed to.
flow into the pan or trough C'. The pans or troughs C', to C, are placed,
in a larger pan or cistern R, containing water, and which is heated by a
double bottom or jacket S, into which steam is admitted, or by blowing
steam into the water in R, or by placing a fire beneath it, or in any,
other suitable manner. F, is a flat pipe, carried horizontally between the
two sets of bands D', to D, and d', to d, and having horizontal branch
pipes fff placed between the endless bands, and perforated with
holes on each side. This pipe is for the introduction of air, which is
directed by it upon the endless bands. The air is withdrawn from the
case by a fan 0, or by an air pump, or other suitable means; or,
instead of being drawn out at O, it may be forced in through the
pipe F, or the air may be both forced in at F, and drawn out at O.

page_text: The air is not to be heated above 212 degrees of Fahrenheit's thermo-
meter, and may be employed at a much lower temperature. Cold'air
may be employed, but the operation is then slower. When it is
required to conduct the evaporation in a partial vacuum, an airpump
is connected to the casing at O, and the entrance of the air is checked
by partially closing the pipe F, by means of a valve; which is not
shewn in the Drawing. Orthis valve may be entirely closed, wlien it
is required to conduct the evaporation in a partial vacuum, and-with-
out the access of air. Tlie solution 'is' carried on by the action of the
bands and 'scrapers until it arrives at the last bands D', and d. K, isɛ
a small, trough or pan, which receives the concentrated cane juice ör
other saccharine solution from the last bands D, and d; and from
this trough it passes over a steam pipe. Q, into the pan or compart-
ment K, 'whence it is drawn off for the purpose of being crystalized or
otherwise treated. By proceeding in the manner above described the.
cane juice or other saccharine solution is rapidly concentrated, without
the "necessity of exposing it to a temperature so high as its boiling
point, or as the boiling point of water. Although I consider it preferable
to employ several bands in succession, as above described, yet the whole
operation may be performed with a single band, such as D', by intro-
ducing the saccharine solution at once into the pan C. I have described
the Invention chiefly with regard to the evaporation of cane juice and
other saccharine solutions, but it is obvious that other liquids may be
evaporated in a similar manner and by the same apparatus.
Having now described the nature of my Invention, and in what
manner the same is to be performed, I wish it to be understood that I
do not claim as my Invention the evaporating of liquids by means of
warm air, nor do I claim generally the application of endless bands for
that purpose; but what I claim is,--
Firstly, the mode or modes herein-before described of evaporating
cane juice and other liquids in a partial vacuum, and at a temperature
not exceeding 212 degrees of Fahrenheit's thermometer, by means of
currents of air applied in apparatus constructed as herein-before
described in reference to Figures 1, and 2.
Secondly, the mode or modes herein-before described of evaporating

page_text: cane juice and other liquids by means of currents of air at a tempera-
ture not exceeding 212 degrees of Fahrenheit's thermometer, acting in
conjunction with endless bands and scrapers, in manner herein-before
described.
Thirdly, the mode or modes of constructing apparatus for evaporating
cane juice and other liquids, consisting of an evaporating vessel with a
perforated false bottom, connected by a chamber with a series of tubes,
and the whole immersed or contained in a pan or casing, which has no
communication with the interior of the apparatus, but which is adapted
to contain the heating medium, as herein-before described in reference
to Figures 1, and 2.
Fourthly, the mode or modes of constructing apparatus for evapo-
rating cane juice and other liquids, consisting of an endless band
partially immersed in the liquid and partially exposed to a current of
air, and acting in connection with a scraper, whereby the solid and
liquid matters, or a portion of them, are removed from the band, and
prevented from returning into the vessel from which they have been
raised by the band, in manner herein-before described. And I claim
such apparatus, whether constructed with a single band and scraper
or with several bands and scrapers arranged in succession, as herein-
before described.
In witness whereof, I, the said John Aspinall, have hereunto set
my hand and seal, this Thirty-first day of March, in the year of
our Lord One thousand eight hundred and fifty-three.
Witness,
CHARLES COWPER,
20, Southampton Buildings.
Chancery Lane,
London.
JOHN ASPINALL. (L.S.)