IMPROVEMENTS IN THE MANUFACTURE OF SUGAR AND IN APPARATUS THEREFOR
Year: 1885

page_text: COMPLETE SPECIFICATION.
I, WILLIAM ROBERT LAKE of the firm of Haseltine, Lake and Co Patent Agents,
Southampton Buildings, in the county of Middlesex do hereby declare the nature
of my invention for "IMPROVEMENTS IN THE MANUFACTURE OF SUGAR AND IN
APPARATUS THEREFOR" and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement
-
This invention comprises an improved process of manufacturing hard sugar from
soft sugars or granulated sugars or mixtures thereof, and convenient apparatus for
employment in carrying out the said process
The process, by which hard white sugar is obtained in blocks or bodies having
marked crystalline surfaces, is especially valuable as a means of transforming into
hard sugar the so-called "A" coffee sugars and granulated sugars, which can be
produced by a single refining operation from sugars of comparatively low grades
The first part of the invention consists in causing soft sugars or granulated
sugars, or mixtures of such sugars, as the case may be, to absorb or be charged with
a more or less highly concentrated hot pure sugar solution, or so-called white
liquor, which is then permitted to cool off, whereby a portion of the sugar of which
the white liquor is composed, and which is incapable of being held in solution at
the lower temperature, crystallizes throughout the mass of soft sugar, firmly
cementing the particles of soft sugar to each other, and producing a body of hard
Bugar having the peculiar glistening appearance due to the presence of crystals not
only upon its exterior, but also upon its planes of cleavage, when broken
the crystallization has ceased, the excess of white liquor is drained off by any of the
usual methods, and the resultant product of hard sugar, after being dried, may then
be broken or cut into blocks or pieces of the desired size and shape
After
The charging operation may be performed by introducing the white liquor
directly into a mould or box of any desired form and size, in which the soft sugar
or granulated sugar is deposited, or the soft sugar or granulated sugar may be first
formed into prisms, tablets or cakes of any required size, and these cakes may then
be charged with white liquor

page_text: Thus in the production of block sugar it is convenient to form the soft or
granulated sugar into tablets or cakes of say five-eighths of an inch thick, twelve
inches long, and eight inches wide This may easily be done by depositing the soft
sugar or granulated sugar in moulds of the desired size, and lightly compacting it
therein by shaking on by slight pressure administered either by a plunger, or by a
roller moved lightly across the surface, after the sugir has been uniformly
distributed in the moulds
In forming granulated sugu into cakes, it may be desirable to slightly moisten
the granulated sugar in order to make its particles more adherent
The moulds containing the sugar are then deposited in a drying oven having a
temperature of say from 130° to 140° Fahrenheit
A few hours subjection to this temperature dries the soft sugar or the moistened
granulated sugar, or the mixture of soft sugar and granulated sugar as the case
may be, so that the particles of sugar adhere to each other sufficiently to permit the
cakes to be removed from the moulds without breaking apart
The cakes are now ready to be charged with the hot sugar liquor This may be
effected by gradually immersing the cakes in a bath of more or less highly con-
centrated hot white liquor contained in an open vessel, or more rapidly by placing
the cakes in a tank or box having an air tight cover, and exhausting the air, and
then introducing into the box or tank a sufficient quantity of concentrated hot
white liquor to completely cover the cakes of sugar deposited therein
After a sufficient quantity of liquor has been introduced into the tank to
completely cover all the cakes of sugar, air may be admitted into the upper part of
the tank above the surfice of the white liquor, and thus atmospheric pressure may
be brought into action to force the white liquor into the cakes
The cooling of the white liquor may be hastened in various ways, as for example
by forcing chilled air into the upper part of the tank, or by removing the tank and
placing it in a bath of cold water, or by removing the cakes of sugar from the
tank, and immersing them in a concentrated cold white liquor, which may be
contained in a tank which is kept surrounded by cold water in order to keep
it cool
As the temperature falls, a portion of the white liquor crystallizes, and this
crystallization may be permitted to go on until the cakes are cooled to atmospheric
temperature
The temperature of the white liquor with which the cakes are charged may be
as high as 220° Fahrenheit or even higher, and the white liquor may, if desired, be
rendered more fluid by being heated above the temperature at which it 18
concentrated
The hotter the white liquor the more sugar it will hold in solution Hence a
concentrated solution of comparatively high temperature will hold in solution a
quantity of sugar largely in excess of the quantity capable of being held in solution
at the lower temperature to which the charged cakes of sugar are reduced before
being drained.
Therefore the quantity of sugar caused to be added to the cakes by the
crystallization of the white liquor with which they are permeated may be varied by
concentrating the white liquor at various temperatures, and also, if desired, by,
varying the time during which crystallization is permitted to go on
If a very hard and heavy product is desired, a white liquor concentrated at high
temperature is employed, and crystallization permitted to go on until the charged
cakes are reduced to atmospheric temperature If however it be desired to effect
the cementation of the constituent particles of the cakes to each other with
only a small addition to the weight of the cake, a white liquor concentrated at
comparatively low temperature is employed or the cakes are removed from the
solution and drained before being fully cooled
After cooling sufficiently to have brought about, the desired crystallization of
white liquor in the cakes, they are drained by introduction into a centrifugal
machine, or by any other convenient method,

page_text: The cakes are then dried at a comparatively low temperature, and will be found
to be more or less hard and to look like loaf sugar, presenting a bright, glistening,
crystalline appearance, not only upon their surfaces, but upon their planes of
cleavage when cut or cracked into blocks.
33
As by this method soft sugars or granulated sugars, or mixtures of such sugars,
are transformed into cakes or bodies of hard sugar by a process of cementation by
crystallization, the product of the process is designated "double crystallized sugar
If it be desired to produce hard sugar in the form of the ordinary sugar loaf, the
ordinary conical mould is employed
The baking of soft sugar or moistened granulated sugar in the moulds is practised
as a matter of convenience when the cakes are to be removed from the moulds
before being charged with white liquor The baking may, if desired, be omitted
if the white liquor is to be introduced directly into the moulds containing the soft
sugar or granulated sugar, as it may be convenient to do, for example, in manu-
facturing hard sugar in the form of loaves In the latter case, if granulated sugar
18 employed, it will not require to be moistened, but may be perfectly dry when
deposited in the mould, and the mould may be provided with an aperture in the
bottom through which the hot white liquor can be introduced
It may be expedient, in some cases, to heat the cakes of soft sugar or the
granulated sugar, prior to the charging with the white liquor, in order to prevent
the too sudden chilling of the white liquor at the instant of its first contact with
the sugar which is to be charged
Simple forms of apparatus adapted for employment in carrying out the process
are illustrated in the accompanying diawings which exhibit appliances for
moulding the soft sugar or granulated sugar into flat cakes of the desired size, and
for conveniently charging the sugar operated upon with hot white liquor, by
depositing them in tanks or boxes of small dimensions from which the air is
exhausted preparatory to the introduction of the hot white liquor, and also
apparatus for manufacturing the soft sugars or granulated sugars into hard sugar
loaves of the usual form
Figure 1 is an isometrical perspective view of apparatus which may be con-
veniently employed for moulding the sugar into cakes
This apparatus consists of a light metallic plate A, upon which is a removable
rectangular frame, composed of the end pieces B, B¹ and the side pieces C, C¹
divided into sections of uniform size by the intermediate transverse birs b b and
the intermediate longitudinal bars c, c
The frame and bars are made five-eighths of an inch thick, and of such
dimensions that the open sections of the frame are say twelve inches by eight
Thus, when the mould frame is placed upon the plate A, there is provided a series
of cavities d, d, each five eighths of an inch deep, and twelve inches long and eight
inches wide The soft sugar or granulated sugar, or a mixture thereof, as the case
may be, is sifted or otherwise distributed equally in these cavities, and is slightly
compacted therein either by passing a roller lightly over the surface of the sugar,
or by light pressure with a plate or plunger, or by shaking the plate
The dislodgement of the mould frame from the plate in the act of shaking is
prevented by the clamping buttons, a, a, a, a, which are pivotted to the plate A
and are adapted to be turned over the end or side pieces of the mould frame
The plate A, supporting the mould frame and the sugar which has been deposited
therein, is next placed in a drying oven and kept at a moderate temperature until
the sugar has become dry The plate A is then removed from the drying oven
and the mould frame is lifted therefrom, thus leaving the cakes of sugar deposited
upon the plate, from which they are easily removed preparatory to being charged
with the hot white liquor
For charging the cakes with the hot white liquor, there may be used numerous
boxes the dimensions of which are regulated
desired number of cakes placed side by side
inches high in the clear inside, will contain
with reference to containing any
Thus a box a foot square, and nine
nineteen cakes twelve inches long!

page_text: eight inches wide and five-eighths of an inch thick placed side by side, and leave
a space of one inch above the cakes so that the box will contain a sufficient
quantity of white liquor to admit of the cakes being wholly immersed therein
An apparatus for charging the cakes of sugar deposited in these boxes is
illustrated in Figures 2, 3, 4 and 5, Figure 2 being a front elevation, Figure 3 a
transverse section on the line y y Figure 2, Figure 4 a vertical section on the
line zz Figure 3, and Figure 5 a view of the underside of the cover of the box,
This apparatus consists of a substantial frame composed of the standards g g¹
firmly united at the bottom to the bed G, and at the top to the horizontal
cross-bar G¹
A stationary vertical screw bolt H is firmly secured at its lower end to the bed G
midway between the standards g g¹ The stationary bolt H engages the suitably
elongated elevating-nut H³, provided with the hand-wheel H2 by means of which
it can be conveniently turned
The upper end of the elevating-nut contains the conical plug h, provided with
the conical head h¹ which is seated in the conical recess & formed in the vertically-
movable table I.
The table I is provided with the laterally projecting tongues 11 1ª which are
seated in the vertical grooves g³ g³ formed in the inner sides of the standards g g¹
The table I supports the box J, and is provided upon its upper surface with the
rectangular ribs,,,, for the purpose of centralising the box relatively to the
stationary cover K which is firmly secured to the underside of the cross-bar G¹.
The under side of the cover K is provided, near its edges, with a strip of elastic
material k, which serves as a packing against which the upper edges of the vertical
walls of the box J are compressed by elevating the table I upon which the box
19 supported The underside of the cover K may also be provided with the
ribs K, K projecting downward a distance of say three quarters of an inch, so
as to bear upon the upper edges of the cakes contained in the box and hold them
down
A pet cock K³ 18 inserted in the cover K to provide for letting air into the upper
part of the box J after the sugar has been charged with the white liquor An air
exhaust pipe 6, inserted through the stationary cover K and provided with a
valve e is connected with an air pump or with a vacuum chamber from which
the air has been previously exhausted Another pipe F, likewise inserted through
the cover K and provided with the valve f, 18 connected with the reservoir
containing the supply of concentrated hot white liquor
The box J is provided upon its front and rear sides, respectively with the
handles J and J* for convenience of moving it
In operation, the box J having been filled with cakes of sugar, is placed upon
the table I which is then elevated by turning the elevating nut H, compressing
the upper end of the box firmly against the packing strip on the under side of the
The valve e¹ being then opened, a partial vacuum is at once established
in the box The valve e¹ being then closed, the valve fis opened for admitting
into the box a proper quantity of the concentrated hot white liquor
cover K
The depth of the box is greater than the width of the cakes consequently the
cakes of sugar will be completely covered by the hot white liquor The valve fis
then closed, and the pet cock K' opened to admit air into the upper part of the
box J, the table I is then lowered sufficiently to clear the upper edge of the box
from the cover
The box may then be removed from the table to a cooling apartment of the
desired temperature, where it may be allowed to cool until the desired crystallization
has taken place, after which the excess of white liquor remaining in the box 19
poured off, and the box is placed in the basket of a centrifugal machine adapted to
receive a number of such boxes The centrifugal machine having been set in
motion the small quantity of white liquor remaining in the cakes 18 expelled
therefrom in the usual manner
.

page_text: If necessary, each of the boxes J may be provided at the bottom with a small
cock J, which may be opened to admit air into the bottom of the box during the
draining operation in the centrifugal machine
The boxes are next taken from the centrifugal machine, and the cakes are
removed from them and separated from each other and deposited in a drying
apartment, where they are kept until they are suitably dry to be cut or split into
blocks
Instead of employing a vertically adjustable table to press the upper edges of the
boxes against a stationary cover, the cover may be made movable and may be
connected by means of flexible tubes with the reservoir of hot liquor, and also with
the pump or vacuum chamber, as illustrated in Figure 6 In the latter case the
cover O may be deposited upon a shelf O¹ in convenient proximity to the table O'
upon which the box O³ containing the cakes of sugar rests, and may be lifted by
hand and placed upon the top of the box and removed therefrom and replaced upon
the shelf after the charging operation has been completed
The cover O may be provided with the downwardly projecting ribs 04, 04,
extending along two of its sides just inside of the packing strip, so that the
ends and exterior sides of the ribs 04, 04, respectively, will serve as guides for
centralizing the cover when it is lowered upon the box thus bringing the parking
strip fairly down upon the upper edges of the walls of the box The mere weight
of the cover will be sufficient to make joint between the top of the box and the
packing strip air tight, especially as atmospheric pressure will hold the cover
closely down upon the top of the box as soon as the air is exhausted therefrom
When the cooling process is to be effected by immersing the charged cakes in a
cold concentrated white liquor, it will be found convenient to deposit the cakes in
a frame which fits into the box in which they are placed in order to be charged,
and for this purpose a charging box is provided say eleven inches high, in the
clear, inside The frame for this purpose is illustrated in isometrical perspective
in Figure 7 It consists of a horizontal bottom-plate J* and two upright plates J³
and J united by the central horizontal bar J', which serves as a handle by means
of which the frame may be lifted
The cakes of sugar to be charged are deposited side by side, edgewise, upon the
bottom plate J' and the frame is then lowered into the box J³, as represented in
isometrical perspective in Figure 8, in which, as will be seen the increased height
of the box enables it to contain the frame without having the horizontal bar J'
interfere with the cover which 18 to be placed upon the box preparatory to the
charging operation This modification renders unnecessary the use of numerous
charging boxes, and also the moving of the charging box from the table upon which
it is supported
In this case, when the charging operation is completed, all that 18 required is to
remove the cover from the box J and lift out the frame by means of the handle J',
and then immerse the frame, and the sugar deposited in it, in a concentrated cold
white liquor contained in a tank of any desired dimensions, which is kept cold
in any convenient way, as for example, by the circulation of cold water around its
exterior sides
The cold white liquor, being a concentrated solution, does not dissolve any of the
sugar from the charged cakes immersed in it, and hence may be usefully and
effectually employed to cool the charged cakes
In manufacturing loaf sugar by this process, the baking may be practised if
desired, but it is not necessary, because the soft sugar or granulated sugar, or
mixtures thereof, can be charged with the hot white liquor without being removed
from the moulds in which it is deposited
Figures 9 and 10 illustrate apparatus for charging with hot white liquor granu-
lated sugar or soft sugar contained in a conical mould, Figure 9 being a vertical
section through the mould and the charging apparatus, and Figure 10 being another
vertical section, on the line z, z Figure 9 In this case a moveable cover P 19
employed which, instead of being lifted and placed upon the top of the mould by

page_text: hand is raised and lowered by a screw nut The mould S is placed in a position
slightly inclined from the perpendicular, with its perforated small end seated in the
bell mouth T of the slightly inclined pipe T', provided with the valve T and con-
'nected with the hot white liquor reservoir The interior of the bell mouth of the
pipe T¹ is provided with the rubber gasket T³, in order that a tight joint may be
made with the lower end of the mould
The side of the mould S is supported in a notch T' formed in a cross bar T of
the frame which supports the mechanism for raising and lowering the cover P
This mechanism consists, essentially, of the actuating nut Q, which is confined
between the horizontal cross bais q and q¹ and engages a screw thread formed
upon the exterior of the bolt P¹, the lower end of which is affixed to the cover P
The object of inclining the mould S is to make it retain its position by its own
gravity, so that in handling it the small end can be seated in the bell mouth T and
the mould tipped back into the notch T and thus be brought into proper allign-
ment with the axis of the bolt P¹, which as shown in Figure 10, is so inclined from
the perpendicular that its axis is in allignment with the axis of the mould when
the latter is in position
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim 18
First The herein-described process of transforming soft sugar or granulated
sugai, or mixtures thereof, into hard sugar, by cementation of the particles of soft
sugar or granulated sugar to each other, produced by the crystallization of sugar
from white liquor which has been introduced, in the form of a more or less highly
concentrated hot solution, into the interstices between the particles of soft sugar or
granulated sugar, and then allowed to cool
Second The herein-described method of cooling cakes of sugar charged with
more or less highly concentrated hot white liquor the same consisting in immersing
such cakes in a concentrated cold white liquor, substantially as, and for the purpose,
set forth
Third Apparatus for charging soft sugar or granulated sugar with hot white
liquor, substantially such as herein described, the same consisting essentially of a
box or receptacle for said soft sugar or granulated sugar, and a removeable cover
adapted to bear upon and make a tight joint with the open top or end of such box
or receptacle, and connections, by means of pipes provided with suitable valves,
respectively with an air pump or vacuum chamber and a reservoir for supplying
the hot white liquor