IMPROVE- MENTS IN REFINING OR TREATING SUGAR AND MOLASSES
Year: 1860

page_text: LETTERS PATENT
to William Green, of Dod Street, Victoria Road,
Limehouse, in the County of Middlesex, for the Invention of "IMPROVE-
MENTS IN REFINING OR TREATING SUGAR AND MOLASSES."
Sealed the 12th March 1861, and dated the 29th September 1860.
PROVISIONAL SPECIFICATION left by the said William Green at tho
Office of the Commissioners of Patents, with his Petition, on the 29th
September 1860.
I, WILLIAM GREEN, of Dod Street, Victoria Road, Limehouse, in the
County of Middlesex, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN REFINING OR TREATING SUGAR AND MOLASSES." to be as
follows:-
One part of the present Invention consists in improvements in decolorizing
treacle or molasses and low syrups, and employing the same for "liquoring" or
whitening sugar; also economising the process of refining sugar by the use of
inferior sugars or syrups to those commonly employed in the manufacture or
preparation of "fine liquor" for the displacement of dark syrups from "titlers "
and other kinds of refined sugar.
In decolorizing syrups by means of animal charcoal they are not generally
allowed to remain stationary while in contact therewith, or if so only for a short
space of time, but are caused to percolate through the charcoal and run off in
a small continuous stream until the whole of the syrup to be operated upon by
[Price 8d.]

page_text: "
The chemical
in a cold or
vessels in a
a given quantity of charcoal has passed through. Now by the present inven-
tion I decolorize treacle or other saccharine fluids by keeping the same for a
much longer period in contact with the animal charcoal, the time prefered
being from about three weeks to a month. When treating "fine liquor' or
syrups the decolorizing process may be expedited and improved by the use of
two or more charcoal cisterns and passing such liquors or syrup successively
through and through each, either continuously or at intervals. The cistern
employed for completing the decolorizing in one operation should be used
before being refilled for the commencement of the operation in a succeeding
charge. In decolorizing treacle or syrups by passing them through a series of
cisterns it is well to employ separate tanks in connection therewith capable of
holding certain fixed but increasing quantities for receiving the first runnings
from each cistern. Instead of animal charcoal or in combination therewith, I
sometimes employ chemical bleaching agents for decolorizing treacle, those
prefered being the phosphate of soda and "Nash's finings."
decolorizing agents having been mixed with the treacle either
heated state it is well to let it stand for some time in shallow
warm atmosphere. After about a week it may be run gently off, and if
necessary, passed through animal charcoal. Perfumes of a harmless character,
as those extracted from various flowers, may also be mixed with the decolorized
treacle and liquors for preventing the unpleasant smell common to many
kinds of low sugar as "bastards" and "pieces" when first knocked out of
the mould. Whatever chemical agents be employed care must, however,
be taken that they be not of a nature deleterious to the sugar upon
which such treacle is to be used, or to the syrups which drain therefrom.
When the decolorized treacle or syrups are not sufficiently thick they may be
evaporated either in vacuo at a low temperature, or by exposure to warm air
either in shallow vessels or other suitable apparatus. A drum provided with
perforated moveable floats capable of rotating in the fluid and exposing thin
films to a current of warm air will answer this purpose. If evaporated in
vacuo the surface through which the heating media passes should be increased
either by an additional coil of pipes or other equivalent means, or the
treacle or syrup may be caused to pass over a series of inclined or other
suitably arranged surfaces, above or near to which but not in immediate con-
tact with the said treacle or syrup, is a heated surface or surfaces. In a
convenient part of such apparatus an air-pump or other exhausting contrivance
is to be placed for drawing currents of warm air over the fluid or producing a
vacuum or partial vacuum. Such arrangements for evaporating at a low tem-
perature are also applicable to ordinary liquors or syrups.

page_text: In a former Patent granted to me, and bearing date May 30th, 1859, I
claimed the use of decolorized treacle for "liquoring" inferior sugars generally
termed "bastards" and "low pieces"; I now propose by the present Invention
to employ decolorized treacle or low syrups decolorized as herein-before de-
scribed for liquoring superior kinds of sugar. The drippings from sugars so
treated may be mixed with "tips" and other syrups in the usual way, and made
into sugar, but I prefer to decolorize them as herein-before described previous to
boiling & to mix them with the syrups which otherwise would have been used
for "liquoring "such said "pieces."
In liquoring "bastards" with decolorized treacle the sugar should first be
allowed to drain for a day or two. The tops or crust on the surface of each
mould is then to be loosened and levelled and about a quart of the said treacle
poured thereon. When this has entered, fresh portions may be successively
applied until each mould has received the quantity intended to be used
thereon. From six quarts to two gallons is generally found sufficient for
ordinary moulds. While the decolorized treacle is being applied to "bastards"
or "pieces" it is well to keep the room in which they drain at a lower tempe-
rature than usual, from 80° to 90° Fahrenheit being sufficient. When the
whole of the liquor has entered below the surface the temperature may be
raised or the moulds removed to a warmer room. It being important that only
a given quantity of decolorized treacle or syrup be employed on each mould
and that it be gently applied, it may in some cases be advisable to use for the
purpose a measure, one with a double bottom, the uppermost one being pro-
vided with a cock and the lower one perforated being prefered.
In some cases, but especially so when working with a centrifugal machine,
the treacle having been decolorized is to be mixed in certain given quantities
with the liquor or syrup before being boiled, or with the "skippings" after
boiling. Thus, supposing that seven per cent. be the average yield of treacle,
a like per centage of decolorized treacle is to be added to the syrup or sugar
as before mentioned. When to be mixed with the "skip" in the heater I
prefer that it be first concentrated at a lower temperature to about 48° Beaume.
In some cases a portion may be thus mixed, and the remaining portion applied
to the sugar while in the centrifugal machine; or if superior kinds of raw sugar
have been used the whole of the decolorized treacle may be applied to the
sugar while in the centrifugal machine.
In order to obtain a "liquor" sufficiently bright and free from color for
"titlers" and other kinds of white sugar it is customary to dissolve refined
sugar, and after "blowing up" the liquor made therefrom to pass the same
through animal charcoal. By the present Invention I make "fine liquor"

page_text: from inferior syrups or brown sugar by first "blowing up" and filtering the
same, and then decolorizing them as herein-before described, thus permitting
of the "lumps, tips and scrapings being ".stoved" or crushed and sold as
refined sugar.
In decolorizing treacle or making "fine liquor" according to this Invention
the charcoal cisterns should be of greater diameter or width than height and
kept in a warm atmosphere from 90° to 110° Fah. being prefered.
Instead of the gutters now employed for conveying the "skip" from the
pan to the "heater" or other receiving vessel, I propose to employ one divided
into a series of narrow compartments, between the alternate spaces of which
steam or other heating media is free to circulate.
SPECIFICATION in pursuance of the condition of the Letters Patent, filed
by the said William Green in the Great Seal Patent Office on the 28th
March 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
GREEN, of Dod Street, Victoria Road, Limehouse, in the County of Middlesex,
send greeting.
WHEREAS
•
Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the 29th day of September, in the year of our
Lord One thousand eight hundred and sixty, in the twenty-fourth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said William Green, Her special licence that I, the said William
Green, my executors, administrators, and assigns, or such others as I,
the said William Green, 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 "IMPROVE-
MENTS IN REFINING OR TREATING SUGAR AND MOLASSES,' upon the condition
(amongst others) that I, the said William Green, my executors or administra-
tors, 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.

page_text: NOW KNOW YE, that I, the said William Green, 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, that is to say:-
One part of the present Invention consists in improvements in decolorizing
treacle or molasses and low syrups, and employing the same for "liquoring" or
whitening sugar. The low syrups are obtained by boiling or otherwise, con-
centrating the waters used for washing animal charcoal after it has been
employed for decolorizing syrups. Usually such wash waters, until they reach
about 2° Beaume, are boiled up with the "bastards," after which they are
allowed to run to waste. I have found, however, that notwithstanding such
waters at the above density possess. no sweetness perceptible to the taste; they
nevertheless contain a certain quantity of low syrup or saccharine in icilage
which may be profitably extracted. Such low syrups though deficient in
sweetness for many of the purposes to which treacle is applied is nevertheless
sufficiently rich to serve as a decolorizing agent, and for various other purposes,
as the flavouring or coloring of malt or other liquors and spirits, the manu-
facture of blacking, etc.
By this Invention I also purpose to economize the process of refining by
the use of inferior sugars or syrups to those now employed for the manufac
ture of "fine liquors;" such sugars or syrups to be decolorized, as herein-after
described. In order to obtain good white sugar it is necessary that the "fine
liquors "used thereon for displacing coloring matter be bright and colorless,
hence, either "lumps or raw sugar of a superior quality are generally used
in its manufacture.
"2
In decolorizing syrups by means of animal charcoal they are not generally
allowed to remain stationery while in contact therewith, or if so, only for a
comparatively short space of time, but are permitted to pass through the
charcoal and run off in a small continuous steam, until the whole of the syrup
to be operated upon by a given quantity of charcoal has passed through. Now,
by the present Invention, I decolorize treacle or other saccharine fluids by
keeping, the same for a much longer period in contact with the animal char-
coal; the time preferred for treacle or "fine liquor" being from three weeks
to a month. When treating fine liquor' or syrups,. the decolorizing process
may be expedited and improved by employing two or more charcoal cisterns,
and passing such liquors or syrups successively through and through each,
either continuously or at intervals. The cistern employed for completing the
operation in one charge should be employed before being refilled for the
commencement of the operation in a subsequent charge. Thus, supposing

page_text: that ten tons of sugar reduced to a liquid state is to be converted into fine
liquor,' five cisterns, each capable of holding two tons of animal charcoal,
should be used. The whole of the ten tons of liquor is then to be passed
through the first cistern and conveyed into seperate tanks, by preference, five
in number; No. 1 to contain the first runnings, and that most free from color.
The whole of the ten tons of liquor is then to be passed through the second
cistern, that from tank No. 1 passing first. The first runnings from the second
cistern may now be conveyed to a seperate tank for use, as may also the first
runnings from each of the other cisterns. Thus, in proportion, as the last
cisterns of the series have to act upon darker syrups, so in proportion will the
quantity upon which they will have to operate diminish. The quantity of
animal charcoal to be employed will, of course, depend upon the quality of the
syrups to be decolorized. If very low sugars be used it is in some cases
.necessary to keep the syrup in contact with about its own weight of charcoal
for several days, and then pass them through a series of cisterns, as before
described.
Instead of animal charcoal, or in combination therewith, I sometimes employ
chemical bleaching agents for decolorizing treacle, those preferred being
'Nash's finings,' or the phosphate of soda. The chemical decolorizing agents
having been mixed with the treacle it is well to let it stand for some time in
shallow vessels kept in a warm room. After about a week (more or less,
according to the depth of the vessels) a scum and a precipitate will have
formed, and the clear decolorized treacle may then be run gently off. What-
ever decolorizing agents be employed care must be taken that they be not of
a nature deletrious to the sugar upon which such treacle is to be used, or to
the syrups which shall drain therefrom. When the treacle or low syrup are
decolorized, if not sufficiently thick, they are to be concentrated either in
vaccuo at a low temperature or by exposure to warm air, either in shallow
vessels or other suitable apparatus.
Several arrangements suitable for this purpose, but which are also applicable
for concentrating other syrups or liquors, are shewn in the accompanying Sheet
of Drawings.
Figs. 1 and 2 represent an apparatus, in which the evaporation is carried
on in a large shallow vessel fitted on to and forming part of a tubular boiler.
Fig. 1 is a longitudinal elevation, partly in section; and Fig. 2, a sectional
end elevation. The letters in the respective views relate to the same parts.
A is the boiler, which, by preference, is made upon the tubular principle,
and of any approved plan. It has a flat top, which serves also as the bottom
of the evaporating vessel B, and extends beyond the boiler and over the flue.

page_text: The flames and heated air having passed through the two bottom rows of tubes
and returned through the upper two rows, pass into the flue C, where they
heat the bottom of the evaporating vessel, and also the steam pipe D; thus,
to a certain extent superheating the steam before it enters the pipes E, E, con-
tained in the evaporating pan. It will thus be seen that the whole effective
power of the heat produced will be rendered available before leaving the
apparatus, an important consideration where a great quantity of water is to
be evaporated economically, as in the case of wash waters, or where fuel is
scarce, as in most sugar-producing countries. In some cases the fluid to be
concentrated may, in the first place, be pumped into the boiler for the genera-
tion of steam instead of water; but in such cases the outlets for the steam
should either be kept partly open, or, if closed, care must be taken that steam
only of a limited pressure be formed. When desired, the fluid may be con-.
veyed to the evaporating vessel above the boiler through the pipe F. This
may be done by simply closing the steam outlet, thus permitting a sufficient
pressure to act upon the fluid to cause it to rise.
Fig. 3 represents a vacuum pan, partly in section, with improvements in the
method of applying steam thereto. The primary object of this arrangement
is to obtain a larger amount of heating surface than is now employed, so as to
facilitate the boiling operation, and permit of steam of very low temperature
being used. The novelty of this arrangement will be seen in the construction
of the tubes A, A, which are made of much greater depth than width. The
flat tubes or recesses may be arranged either in coils or in seperate rings, and
placed at a short distance from the bottom of the pans; or they may be made
to form a part of the bottom, as shewn in the Drawing. In the latter case
spaces B, B, must be provided beneath the recesses, in order to permit of the
circulation of the sugar in the pan; and small air pipes should be provided to
prevent the accumulation of air in the said recesses. When pans are made
upon this principle I prefer to cast the bottom in loam in one piece, whereby
the expense of the pan will be greatly lessened, at the same time that its
efficiency is increased.
Another arrangement for concentrating syrups at a low temperature is
shewn in Fig. 4; this is a modification of the pan invented and patented by
Mr. A. W. Gadesden, and known as the Gadesden pan. Instead of forming
the drum of a series of bars or rods, as is usual, I form them with one or more
series of moveable floats A, A, around their circumference. These floats I
prefer to have made in the form of combs, so that as the drum revolves in the
fluid contained in the pan B they take up upon their surface thin films
thereof, and expose the same to the action of a current of hot air. The air is

page_text: heated in its passage through the pipes C, C, by the same are as heats the
fluid in the pan, and is forced through the several pipes on to the syrup
through the slotted tubes D, D, by means of a fan or other suitable contrivance.
The apparatus represented Fig. 5 is another arrangement for evaporating
at a low temperature. It consists of a series of inclined planes, by preference,
with corrugated bottoms, and provided with jackets for the circulation of
steam or other heating media. A, A, are the inclines; B, B, are flat
These
tubes attached thereto and communicating with the liquor tank C.
tubes are provided with regulators for adjusting the flow of the syrup from the
tank to the inclines. The apparatus should be placed in a room kept at a
high degree of temperature, and may either be connected with a chimney shaft,
as shewn in the Drawing, or with any other convenient exhausting apparatus.
Its action is as follows:-The syrup to be concentrated having been run into the
tank C the regulators are opened, and a series of thin streams permitted to
flow on to the inclines, from which they will run into the tank D, and from
thence be pumped into the tank C, the circulation of the syrup continuing
until sufficiently concentrated. The air of the room in which the apparatus is
placed being warm, a continuous current thereof will be drawn over the syrup
as it flows, and thus a rapid evaporation at a low temperature will be effected.
The bottoms of the inclines should be of corrugated metal, as shewn in Fig. 7,
& provided with a steam jacket. Or, instead of the above arrangement, the
inclined planes may be arranged in the form of a screw, & the syrup caused to
pass slowly over the same until sufficiently concentrated.
The flat
Another arrangement more particularly suited to the construction of low
syrup from wash waters, is shewn in Fig. 6. This consists of a shallow vessel
provided with a flat coil, or a series of coils, of much greater depth than width
for the passage of steam, boiling water, or other heating media.
coils are made, by preference, of corrugated metal, in order to obtain sufficient
strength with lightness. In making flat coils for this purpose a long band of
metal is attached to a roller of the pattern of the intended corrugations. In
contact with the pattern roller, and regulated by springs and weighted levers,
is either a die or another corresponding roller. Upon the pattern roller being
turned the metal band attached thereto will be drawn under the other roller
or die, and so receive the intended corrugations, together with laps or selvages
Instead of allowing the
for facilitating the union of two pieces together.
metal band to pass through the machine, it is permitted to coil round and
round the pattern roller, thereby forming one part of a continuous coil. The
two pieces may be united either by rivetting or any other convenient means.
In this way evaporating pans having a large amount of heating surface may

page_text: be very cheaply made. In some cases also a similar arrangement to that
described in connection with vacuum pans, may be used as open pans for con-
centrating wash waters and syrups.
In a former Patent granted to me and bearing date May 30th, 1859, I
claimed the use of decolorized treacle for "liquoring" inferior sugars,
generally termed "bastards" or "low pieces." I now propose by the present
Invention to employ decolorized treacle, or low syrups decolorized, as herein-
before described, for 'liquoring' superior kinds of sugar. The drippings
from sugar so treated may, if so desired, be mixed with the 'tips' and other
kinds of syrup, and be converted into sugar in the same manner as when
ordinary liquor or syrups are employed for 'liquoring.' It is better, however,
that such drips be decolorized, as herein-before described, and mixed with the
syrups, which otherwise would have been employed for liquoring' such said
pieces. In liquoring bastards with decolorized treacle, the sugar should
first be allowed to drain for a day or two. The top or crust upon the surface
of each mould is then to be levelled, and about a quart of the said treacle
poured thereon. When this has entered, fresh portions may be successively
applied until each mould has received the quantity intended to be used
thereon. From six quarts to two gallons being generally sufficient for
ordinary bastard moulds. While the decolorized treacle is being applied it is
well to keep the room in which they drain at a lower temperature than usual,
from 80° to 90° Fahrenheit being sufficient. When the whole of the liquor
has been used the temperature may be raised, or the moulds removed to a
warmer room. It being important that only a given quantity of the de-
colorized treacle be applied each time, it may in some cases be adviseable to
use a measure, one with a double bottom, the uppermost one being provided
with a cock, & the lower one perforated, being preferred.
In some cases, but especially so when working with the centrifugal machine,
the treacle having been decolorized is to be mixed in certain given quantities with
the liquor or syrup before being boiled, or with the skippings' after boiling.
Thus, supposing that nine per cent. be the average yield of treacle, a like per-cent-
age of decolorized treacle is to be added to the syrup or sugar, as before men-
tioned. Notwithstanding, however, that the said decolorizing process greatly
promotes crystallization, exposure to a high temperature rapidly injures the
treacle so treated. I, therefore, prefer to concentrate the said treacle to a
greater density at a low temperature before mixing it with the 'liquor or 'skip.'
Or, a portion of such nine per cent. of treacle may be mixed, as before men-
tioned, and the remaining portions applied to the sugar while in the centrifugal
machine. In some cases also, as when the raw sugar used is good, the whole of

page_text: the decolorized treacle may be applied to the sugar while in the centrifugal
machine.
Instead of the gutters commonly used for conveying the skip' from the
pan into the heater' or other receiving vessel, I propose to make them with
a series of narrow compartments, between the alternate spaces of which steam
is free to circulate.
WILLIAM GREEN. (L.S.)