Improvements in the Manufacture or Production of Raw or Refined Sugar, and Apparatus to be used therein
Year: 1890

page_text: Date of Application, 23rd Jan.,
1890
Complete Specification Left, 7th Feb., 1890-Accepted, 19th Apr.,
1890
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture or Production of Raw or Refined
Sugar, and Apparatus to be used therein.
I, ANDREW FAIRGRIEVE of 40 Marchmont Crescent in the City of Edinburgh,
North Britain, Sugar Expert and Analytical Chemist do hereby declare the nature of
this Invention to be as follows:-
"
My Invention has for its object the simplification of the system or process for
producing (A) sugar from the juice of the cane, the beetroot or other saccharifirous
plants and (B) refined from raw sugar, by substituting (1) a "flour sugar" for the
grainy" at present made; (2) a drying apparatus in lieu of the centrifugal
machines and the other accessories of that method of working and (3) by
converting the whole of the "sweets" contained in the "liquor" from the said
juices or in the "liquor" from the said raw sugar at one operation into dry sugar, so
greatly simplifying the processes of production largely increasing the yield from the
original or raw material and effecting a marked economy in the cost of production.
Ordinarily juice extracted from the cane, beetroot or other materials by diffusion or
pressage is after
proper clarification and subsidence or filtration concentrated in
an open "battery" or vacuum apparatus to a density of 22 to 30 degrees Beaumé.
At this stage the juice is known technically as "liquor" and according to the quality
of the sugar desired undergoes either a further purification or is at once ready for
the open or vacuum
"strike pan. In the refinery liquor (the solution of raw
sugar in water) is after having passed through the "charcoal" or purifying and
decolorising filtration, synonymous with and ready for the same operation as the
"liquor" of the manufactory.
as
"
In the
"
Dry sugar from the "liquor" of the manufactory or refinery in the ordinary
system or process of work, is obtained much after the following manner.
"strike" pan the "liquor" is gradually but quickly concentrated to the "proof"
point (verge of crystal formation) about 44 to 46 degrees Beaumé and the charge
("full of pan") is either completed in such state or at an early stage, minute crystals
are forced to form in a quantity of the concentrated "liquor" and "built" upon
until the pan is full. The contents of the "strike" pan are discharged into receivers
"smooth" or "grained" massecuite according to circumstances. The "smooth
is allowed to stand until crystallization is effected and the "grained" is either
allowed to stand for a short period to strengthen the crystals already formed or to
await the succeeding operation. Once matured and ready for treatment, both the
"smooth" and the "grain" boiled massé-cuite are carried to the centrifugal machines
in which the crystals are separated from their superabundant syrup or mother liquor.
Washed and dried in the centrifugal machines the crystals, as dry sugar, are next
cooled, mixed and filled into packages for the market. Returned to the "strike" pan
either after or without further treatment the syrup or mother liquor is again concen-
trated and so on until exhausted of "grain" when the residue is sent to the distillery
or into consumption as syrup or treacle. It is on an improved treatment of the
liquor and masse-cuite formed by its concentration, that my Invention is based.
Instead of proceeding as above described for the production of dry sugar from
the liquor of the manufactory or refinery, the system or process as hereinafter is
substituted.
Concentration of the "liquor" is effected in a closed pan, heated by steam of say
10 to 15 lbs. pressure per square inch under vacuum and in the speediest manner and
at the lowest temperature practically possible.
Having reached the "proof" point (verge of crystal formation) without however
allowing grain to form and the pan being full up to the practical working limit feeding

page_text: is discontinued and the vacuum then carried is quickly though gradually lowered to
zero in such manner as will keep the contents of the pan regularly about the consistency
arrived at before the lowering of the vacuum (i.e. the "proof" point). Great care and
attention requires to be exercised in carrying out this operation, although it is simple
and easily performed.
The increasing temperature due to the falling vacuum should never be permitted
to so thin the concentrated "liquor" as to heat it too highly or cause it to froth.
If frothing should occur it can be remedied by the admittance of a small jet of steam
or a little olive oil.
Neither should the liquor be allowed to become so thick as to force grain to
separate out. The vacuum having fallen to zero and the "proof" point or verge
of crystal formation at the natural boiling temperature of the concentrated "liquor"
having been attained (with proper attention both should close together) the masse-
cuite is ready for the drying apparatus. Before receiving any of the masse-cuite the
interior of this apparatus must be thoroughly heated.
Steam at a pressure of say 15 lbs. per square inch is let into the steam space and
mixing stirrers having been lowered into position the masse-cuite or concentrated
liquor is run direct from the pan into the space to a depth of say about 6 inches. The
arms carrying the mixing stirrers are then set in motion through a suitable shaft and
gearing at a speed preferably of about 40 to 50 revolutions per minute. By means
of this arrangement and the quick motion of the mixing stirrers, the masse-cuite in
the drying apparatus is rapidly and continuously turned over and over and exposed
to the action of the heat and the air. Almost immediately the thick viscous state in
which the masse-cuite entered the drying apparatus is changed to that of a dry free
sugar in a soft flaky and very fine state of division to the touch as fine as flour and in
the state best suited for its economical use in consumption.
Lumps formed in the course of the drying are broken up by rollers attached to each
alternate arm and behind the mixing stirrers carried by it. 20 to 30 minutes suffices
for the mixing and drying operation. The arms with the mixing stirrers are then
raised out of the dryer and the dry sugar is thereafter cleared away through
an opening. When discharged from the drying apparatus the dry sugar falls on to
a set of sieves placed underneath. These sieves stand the one directly beneath the
other, the widest meshes uppermost and with the motion of the one below contrary
to that immediately above."
Besides the usual back and forward action, these sieves should be so arranged as to
slightly oscillate and "dump" much after the manner of the self acting machine for
arranging wooden match sticks in the sets for heading. Residue or lumps left over
at the sieves are returned to the drying apparatus and worked up with succeeding
charges from the sieves the fine dry sugar is sent to a centrifugal or other cooler,
through which it passes into hoppers and thence into packages.
Comparison of the ordinary with my new system or process for the making of dry
sugar from the "liquor" of the manufactory or refinery demontrates the extreme
simplicity and economy of the latter over the former, effecting as it does, a great
saving in cost of required plant space fuel and hand labour. From the "strike" pan
to the filling into packages is one direct and continuous operation the only hand
labour necessary being the attendance to the machinery and the emptying of the dry
sugar from the drying apparatus. There is no reboiling of syrup or mother liquor
and no syrup residues, while the dry sugar produced is in the state best suited for
economical use.
Where my new system or process is adopted in order to secure the best results and
bring up the colour of the dry sugar to that of the washed sugar of the ordinary
centrifugal system or process, there must be a rational and scientific treatment of the
original or raw material. In the manufactory the juice must be carefully clarified,
freed from all solid impurities, and concentrated to the state of "liquor" as quickly
and at the lowest temperature practically possible. Then (and whether or no there
be after charcoal filtration) the "liquor" itself should be subjected to a purification
with some reagent such as superphosphate of lime and filtered previous to entering

page_text: the "strike" pan. And in the refinery the "liquor" in its raw state should be
clarified and partially decolorised by the use of superphosphate of lime, or other
reagent having a like effect, and then filtered. Passing through the charcoal the
system should be such as to secure the extraction of all colour practically possible
which is best arrived at by arranging the char filters for an automatic double or treble
filtration. So long as the "liquor" coming from the char filters first put in use is
colourless and bright, it is run to supply the "strike" pan but immediately it begins
to shew colour or dulness, it should be passed through another filtration, the fresh
charcoal of which will effect its proper purification. Running through the first filters
is continued until their action becomes decidedly sluggish, or they fail to extract say
50 per cent. of the colour of the raw "liquor." Then the raw "liquor" feed is shut
off them and the filters are drained and washed off with boiling water in the usual
way the washings, so long as it is sweet being sent over the succeeding filters put in
use. Following the foregoing system gives the most economical results from charcoal
which after use must be thoroughly and carefully washed before being sent to the
revivifying kilns.
As to the general quality of the dry sugar produced by my new system or process that
from the manufactory will never vary to any extent will accord almost entirely with
the nature and proper treatment of the juice extracted from the cane, beetroot or
other sacchariferous plants. But in the refinery different qualities of raw sugar can
be mixed for melting so as to turn out a product to meet the requirements of the
market.
D
30
1
r T
1000
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in the Manufacture or Production of Raw or Refined
Sugar, and Apparatus to be used therein.
I ANDREW FAIRGRIEVE of 40 Marchmont Crescent in the City of Edinburgh
North Britain Sugar Expert and Analytical Chemist do bereby declare the nature of
this 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 has for its object the simplification of the system or process of
producing (A) sugar from the juice of the cane, the beetroot, or other sacchariferous
plants and (B) refined from raw sugar by substituting (1) a "Flour sugar" for the
"grainy" at present made (2) a drying apparatus in lieu of the centrifugal machines
and the other accessories of that method of working; and (3) by converting, the
whole of the "sweets" contained in the "liquor" from the said juice or in the "liquor"
from the said raw sugar at one operation, into dry sugar, so greatly simplifying the
processes of production; largely increasing the yield from the original or raw
material; and effecting a marked economy in the cost of production. Ordinarily
juice extracted from the cane, beetroot or other sugar yielding plants by diffussion or
pressage is, after proper clarification and subsidence or filtration, concentrated, in an
open "battery" or vacuum multiple effect apparatus, to a density of from say 22 to
30 degrees Beaumé. At this stage the juice is known technically as "heavy juice"
or "liquor," and, according to the quality of the sugar desired, undergoes either a
further purification, or, is at once ready for the open or vacuum "strike" pan. In
the refinery, liquor (the solution of raw sugar in water) is, after having passed
through the "charcoal" or purifying and decolorising filtration, synonymous with,
and ready for the same operation as the "liquor" of the manufactory.
Dry sugar from the "liquor" of the manufactory or refinery, in the ordinary
system or process of work, is obtained much after the following manner. In the
strike"
pan the "liquor" is gradually but quickly concentrated to the "proof"
point—(verge of crystal formation)—about 44 to 46 degrees Beaumé, and the charge

page_text: "
("full of pan") is either completed in such state, or, at an early stage, minute
crystals are forced to form in a quantity of the concentrated "liquor," and "built
upon until the pan is full. The contents of the "strike" pan are discharged into
receivers as
T'he
smooth" or "graine!" misseruite, according to circumstances.
"smooth" has to stand until crystallization is effected and the "grained" is either
allowed to stand for a short period to strength in the crystals already formed, or to
await the succeeding operation. Once matured and ready for treatment, both the
"smooth" and the "grain" boiled masse-cuite are carried to the centrifugal machines,
in which the grain or crystals are separated from their superabundant "syrup" or
"mother liquor." Washed and dried in the centrifugal machines the grain or
crystals, as dry sugar, are next cooled, mixed, and filled into packages for the market.
Returned to the "strike" pan, either after or without further treatment, the "syrup'
mother liquor" is again concentrated and so on until exhausted of "grain
crystals when the residuo is sent to the distillery or into consumption as syrup or
treacle.
or
**
"
"
or
It is on an improved treatment of the liquor" and masse-cuite formed by its
concentration that my invention is based. Instead of proceeding as above described
for the production of dry sugar from the "liquor" of the manufactory or refinery,
the system or process as hereinafter is substituted.
"
Concentration of the "liquor" is effected in a closed pan, heated by steam of
say 10 to 15 lbs. pressure per square inch, under vacuuin, and in the speediest
manner, and at the lowest temperature practically possible. Having reached the
proof" point (verge of crystal formation) without however allowing grain to form,
the pan having been filled to the practical working limit, feeding is discontinued and
the vacuum then carried is quickly though gradually lowered to zero, in such
manner as will keep the contents of the pan regularly about the consistency arrived
at before the lowering of the vacuum (i.e. the "proof" point). Great care and
attention require to be exercised in carrying out this operation. The increasing
temperature due to the falling vacuum should never be permitted to so thin the
concentrated liquor as to cause it to froth. (if frothing should occur it can be
remedied by the admittance of a small jet of steam or a little olive oil.) Neither
should the liquor" be allowed to become so thick as to force grain or crystals to
separate out.
$6
ני
:
Having reduced the vacuum to zero, and the "proof" point or verge of crystal
formation at the natural boiling temperature of the concentrated liquor" having
been attained (with proper attention both should close together) the prepared masse-
cuite is ready for the drying apparatus. I do not limit myself to the use of any
particular construction of such apparatus but in the accompanying Drawing I
bave illustrated an arrangement which I have invented specially adapted for the
purpose.
Figure 1 is a sectional elevation and Figure 2 is a half plan of the apparatus.
1 is a pan (which if of iron should have its interior enamelled) into which the
prepared masse-cuite is permitted to run. 2 is an outer casing to the pan 1 and 3 is
a space between the two into which steam or other heating agent such as hot air is
admitted by the pipe 4 fitted with the valve 5 for regulating the admission of the
heating agent. Attached to the pan 1 is a sheet metal guard 6 carried round it to
prevent the contents of the pan 1 from being spilt over its edge.
The outside of the casing 2 is provided with a coating of non-conducting material
kept in place by open wire work or other convenient means as at 7 for the purpose
of preventing as far as possible loss of heat by radiation and thus minimising the
waste of steam due to the occurrence of condensation in the space 3. The floor of
the casing 2 is inclined as shown so that water of condensation may pass into the
pocket 8 and be conducted away by the drain pipe 9.
10 is a cock communicating with the space 3 for the purpose of permitting
the exit of any air which may be in the space 3 when steam is first admitted
thereto.
11 are bearers which rest on the floor 12 and support the outer casing 2 at points

page_text: around its bottom circumference, similar bearers 13 being placed between the pan
and casing 2 in the steam space 3 and above the bearers 11 for the purpose of
supporting the outer circumference of the pan 1. The ring 14 to which the floors
of the pan 1 and casing 2 are connected by their respective flanges 15, 16, rests
on the floor 12 and forms a support for the central portion of the apparatus and an
exit passage for the sugar which is delivered into the funnel 17 and forms also a
support for the footstep bearing 18 of the operating shaft 19 the bearing being
formed with arms 20 which rest upon lugs 21 on the inside of the ring 14 as shewn.
The bearing 18 and its arms 20 are prevented from rotating by lugs 22 between
which the ends of the arms 20 are inserted.
A dome or cover 23 surrounds the exit opening of the ring 14 and prevents the
exit of the masse-cuite. Rings 24 and 25 are secured to the bottom edge of the dome
to strengthen it and form a tight joint with the floor of the pan I, and the upper
edge of the ring 14.
To permit the exit of the contents of the pan the dome 23 is lifted as hereinafter
described.
The operating shaft 19 is rotated from above by bevel gearing or by any other
convenient means. Upon it is fixed a rectangular collar 26 and immediately above
the said collar the shaft is made square (or other non-circular shape) in cross section
for a short distance vertically as shown at 27. Around this squared portion of the
shaft and resting upon the collar 26 is a loose collar 28 with flat sides and having
in it a hole which fits the squared or equivalently formed portion 27 of the shaft 19.
The said loose collar 28 is free to slide vertically upon the shaft, and has rivetted to
its flat sides the four arms 29 stayed together by the ring 30 and bars 31 and
carrying the stirring attachments. Each of these arms 29 is fitted with an eye
bolt 32 with which engage the hooks of suitable lifting gear (not shown in the
drawing) by means of which the arms 29 (with all their attachments) and the
collar 28 can readily be raised out of or lowered into the pan 1. The dome 23
may be lifted or lowered with the arms 29 when the latter are raised or lowered.
For this purpose the two chains 33 are attached to the arms 29 and ring bolts 34
are provided on the dome, with which the hooks of these chains are engaged, when
necessary, so that the dome and arms may be raised and lowered together.
The collar 28 and its arms 29 and their attachments are shewn in readiness to
commence stirring and when the shaft 19 is rotated the squared portion 27 thereof
causes the loose collar 28 and the arms 29 and their attachments to rotate
therewith.
Arms 35 attached to each of the arms 29 carry bars 36 having ploughs 37 formed
upon or fixed to them, the ploughs upon two of the bars are alternate in position
being so placed that the ploughs of each of the other two arms traverse the material
which escapes the ploughs of the arm preceding it.
Removable scrapers 38 are attached to the outer ends of two of the arms 29 and
scrapers 39 are attached to the inner ends of all the said arms for the purpose of
keeping the wall of the pan and the side of the dome free from incrustation, and
two of the arms 29 carry a removable scraper 40 which is fixed to the plough bars
and precedes the ploughs for the purpose of keeping the floor of the pan 1 clean
and preventing any of its contents from escaping the operation of the ploughs.
For the purpose of breaking up lumps I may employ rollers 41 attached to and
travelling with the arms 29, the frames 42 of the rollers being so formed that they
may be readily engaged with or disengaged from the hooks 43 upon the arms.
Each pair of rollers is so arranged that the rollers travel over different portions
of the roller paths.
Before receiving any of the prepared masse-cuite the interior of this apparatas
must be thoroughly heated. Steam at a pressure of say 15 lbs. per square inch
is let into the steam space, and the mixing stirrers having been lowered into
position the prepared masse-cuite or concentrated "liquor" is run direct from the
pan into the drying apparatus to a depth of say about six inches. The arms
carrying the mixing stirrers are then set in motion at a speed preferably of about

page_text: 40 to 50 revolutions per minute. By means of this arrangement and the quick
motion of the mixing stirrers, the prepared masse-cuite in the drying apparatus
ir rapidly and continuously turned over and over and exposed to the action of the
heat and the air. Almost immediately the thick viscous state in which the
prepared masse-cuite entered the drying apparatus is changed to that of a dry
free sugar in a soft flaky and very fine state of division; to the touch as fine as
flour and in the state best suited for its economical use in consumption.
Lumps formed in the course of the drying are broken up by the rollers attached
to the arms whilst the sugar is all kept from too long contact with the heating
surface by the scrapers in front of and at the end of the stirrers. 20 to 30
minutes suffices for the mixing and drying operation. The rollers are lifted out
and the arms with the mixing stirrers are then raised out of the dryer, and the
dry sugar is thereafter cleared away through the opening at bottom. When
discharged from the drying apparatus, the dry sugar should be caused to fall on
to a set of fine sieves placed underneath. These sieves should stand the one
directly beneath the other, the widest meshes uppermost, and with the motion of
the one below contrary to that immediately above. Besides the usual back and
forward action, these sieves should be so arranged as to slightly oscillate and
dump," much after the manner of the automatic machine for arranging wooden
match sticks in the sets for heading. Residue or lumps left over at the sieves are
returned to the drying apparatus and worked up with succeeding charges. From
the sieves the fine dry sugar is sent by elevators or other automatic means to a
centrifugal or other cooler, through which it passes into hoppers, and thence into
packages. Comparison of the ordinary with my new system or process for the
making of dry sugar from the " liquor of the manufactory or refinery,
demonstrates the extreme simplicity and economy of the latter over the former,
effecting, as it does, a great saving in cost of required plant, space, fuel and hand
labour. From the "strike" pan to the filling into packages is one direct and
continuous operation, the only band labour necessary being the usual attendance
to the machinery and the emptying of the dry sugar from the drying apparatus.
There is no reboiling of " syrup or "mother liquor," and no syrup residues,
while the dry sugar produced is in the state best suited for economical use.
"
"
Where my new system or process is adopted, in order to secure the best results, and
bring up the colour and bloom of the dry sugar to that of the washed sugar of the
ordinary centrifugal system or process, there must be a rational and scientific treat-
ment of the original or raw material.
In the manufactory the juice must be carefully clarified, freed from all solid
impurities, and concentrated to the state of "liquor" as quickly and at the lowest
temperature practically possible. Then (and whether or no there be after "charcoal'
filtration) the liquor" itself should be subjected to a purification with some reagent
such as superphosphate of lime and filtered previous to entering the "strike" pan.
And in the refinery the "liquer" in its raw state should be clarified and partially
decolorized by the use of superphosphate of lime or other reagent having a like effect
and then filtered. Passing through the "charcoal" the system should be such as to
secure the extraction of all colour practically possible which is best arrived at by
arranging the charfilters for an automatic double or treble filtration.
So long as the "liquor" coming from the charfilters first put in use is colourless
and bright it is run to supply the "strike" pan but immediately it begins to shew
colour or dulness it should be passed through another filtration the fresh charcoal of
which will effect its proper purification. Running through the first filters should be
continued until their action becomes decidedly sluggish or they fail to extract a
sufficient proportion of the colour of the raw "liquor." Then the raw "liquor" feed
is shut off them and the filters are drained and washed off with boiling water in the
usual way, the washings, so long as they contain "sweets," being sent over the
succeeding filters put in use. Following the foregoing system, gives the most
economical results from charcoal, which, after use, must be thoroughly and carefully
washed before being sent to the revivifying kilns.

page_text: As to the general quality of the dry sugar produced by my new system or process,
that from the manufactory will seldom vary to any great extent as it will accord almost
entirely with the nature and proper treatment of the juice extracted from the cane,
beetroot, or other sacchariferous plants. But, in the refinery, different qualities of
raw sugar can be mixed for melting so as to turn out a product to meet the require-
ments of the market.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In the manufacture or production of raw or refined sugar the treatment of the
concentrated "liquor" or masse-cuite in the vacuum pan in the improved manner
herein before described for producing or turning out the whole of the "sweets" at one
operation in the form of a dry product.
«
2. The manufacture or production of raw or refined sugar by treating the concen-
trated liquor" or masse-cuite in the vacuum pan in the improved manner herein-
before described and thereafter submitting it to the action of heat and air
substantially as hereinbefore described.
دو
3. The manufacture or production of raw or refined sugar by treating the concen-
trated "liquor or masse-cuite in the vacuum pan in the improved manner herein-
before described and thereafter submitting it to the action of stirrers or agitators in a
container or pan heated by steam or other heating medium substantially as hereinbefore
described.
,
4. The general arrangement and combination of parts constituting the apparatus
for submitting the prepared concentrated "liquor or masse-cuite to a heating and
agitating process substantially as hereinbefore described and illustrated in the
accompanying drawings.
5. As a new article or product of manufacture, sugar in a floury form such as is
produced by treatment in the manner hereinbefore described.
Dated this 4th day of February 1890.
A. FAIRGRIEVE.