IMPROVEMENTS IN CRYSTALLIZING AND PURIFYING SUGAR
Year: 1843

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, -I, WILLIAM
RITTER, of 106, Fenchurch Street, in the City of London, Gentleman, send
greeting.
:
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Eleventh day of January, in the sixth year of the reign
of Her said Majesty, did, for Herself, Her heirs and successors, give
and grant unto me, the said William Ritter, Her especial licence that
I, the said William Ritter, my exors, admors, and assigns, or such others
as I, the said William Ritter, my exors, admors, and assigns, should at
any time agree with, and no others, from time to time and at all times
during the term of years therein expressed, should and lawfully might make,
use, exercise, and vend, within that part of the United Kingdom of Great
Britain and Ireland called England, Her Dominion of Wales, and Town of
Berwick-upon-Tweed, and also in all Her Majesty's Colonies and Plantations
abroad, an Invention of "IMPROVEMENTS IN CRYSTALLIZING AND PURIFYING
SUGAR," being a communication from a Foreigner residing abroad; in which
said Letters Patent there is contained a proviso that I, the said William
Ritter, should cause a particular description of the nature of the said Invention,
and in what manner the same is to be performed, to be enrolled in Her
Majesty's High Court of Chancery within six calendar months next and
immediately after the date of the said now reciting Letters Patent, as in and
by the same, reference being thereunto had, will more fully and at large
appear.

page_text: as follows:-
The object of this Invention is,
First, to supersede the use of all complicated, artificial, and expensive
apparatus hitherto employed in the evaporation and boiling of sugar or saccha-
rine liquids; and to obtain, by the employment of the ordinary coppers, even
the most simple fixed or swinging coppers over an open fire, the same or more
beneficial results than have been obtained by boiling sugar or saccharine
liquids in vacuo by means of exhausted coppers, but at the same time my
process is applicable to vacuum boilers.
Secondly, to avoid the expensive and repeated labour hitherto necessary to
bring sugar of a more or less. inferior quality to such a state of purity of colour
or strength as is required to produce either a perfectly pure and colourless
solution of sugar, or refined sugar of the finest quality, such as that called royal
sugar, and to perform at once and by one operation either the complete
separation of the syrup or molasses from the crystallized or crystallizable sugar,
or the purifying of raw sugar, whether colonial or any other kind, without the
necessity of dissolving or boiling it for that purpose, and without the employ-
ment of the usual mechanical or chemical process.
And, thirdly, to accellerate the manufacture and refining of sugar, parti-
cularly of raw or other sugar of a low quality, and to reduce the local space
hitherto required for refining a large quantity of sugar, and so materially to
diminish the expence of manufacture. These several advantages are attained
by the use of certain simple utensils called by me crystallizing and purifying
cases; or vessels, which are respectively herein-after described, and in the
Drawings hereto annexed, and by a new process or treatment used in conjunc-
tion with such cases or vessels, and founded on correct principles applicable to
the nature of crystallizable or crystallized sugar. Numerous experiments have
clearly proved that every solution of crystallized sugar more or less extended by
water, or all liquid containing crystallizable sugar, may be concentrated in boilers
over an open fire and under atmospheric pressure to a point at which the liquor
does not contain more than one part (in weight) of water for three parts (in
weight) of sugar without the crystallizable sugar undergoing the least altera-
tion by the concentration itself; and that if a partial alteration of the crystal-
lizable sugar takes place during the concentration, it must have been produced
by other means.. Other experiments, undertaken on a larger scale, and solely
for the purpose of ascertaining with certainty the causes of the alteration of a

page_text: part of the crystallizable sugar (that is to say), diminution of the quantity
of pure sugar contained in the raw sugar by the process of refining, have also
full proved that the concentration by means of the ebullition of the liquid
cannot be carried beyond the before-mentioned point, (namely, three parts
of sugar to one part of water,) without causing an alteration of a greater
or smaller quantity of the crystallizable sugar; and that this effect is in pro-
portion to the more or less intense and prolonged action of the heat on the
concentrated liquid, and the degree of. purity of the latter. The apparatus of
the boiler, exhausted of air, may diminish but cannot prevent the injurious
effects to the sugar of a concentration carried further. The true and only
cause of the alteration in the sugar consists in the contact of the liquid already
so concentrated with a metallic surface heated above the boiling point of water,
a contact which equally takes place in the exhausted boiler, although the whole
of the liquid taken together shews a lower temperature. The only infallible
means to prevent any alteration of the sugar by boiling is, not to carry the
concentration of the liquid to a point which leaves more. than one part of
water to three parts of sugar. But so weak a concentration or boiling must
induce serious inconvenience in the crystallization and purifying of sugar, and
would render impossible the formation of compact loaves, such as the public
require, if the boiled syrup were submitted to the usual treatment.
This
inconvenience I prevent with the greatest facility by a new mode of treatment,
which I shall presently describe, in combination with the use of my crystal-
lizing and purifying cases or vessels, herein-after also described, by which means
the sugar may be thoroughly purified without having carried the concentration
of the liquid to the weakest proof, nor even to that called candis proof, and
without the use of blood, charcoal, or solutions and strainings now in general
use. By the process hitherto employed it is impossible to give to ordinary or
very low sugars the purity and strength of good clayed sugar fit for the imme-
diate making of fine refined sugar except by repeated labour, which is very
expensive, requires a great length of time, and besides occasions a great altera-
tion or distinction of a considerable portion of the crystallizable sugar, the
consequence of which is, that sugars of a low quality are sold at a price dispro-
portionate to the quantity of pure sugar contained in them, and much lower
than the real value. In order, therefore, to reduce and simplify such a repeti-
tion of labour, and thus to effect a reduction of time and expense, and also to
avoid the alteration of a part of the crystallizable sugars, I employ the utensils
called purifying vessels, herein-after described and shewn in the Drawings
hereto annexed. By means of these utensils and their management, as herein-
after described, the whole of the syrup or molasses can be separated with the

page_text: .
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greatest ease from. the crystals, of the sugar, and the raw sugar, even of the
most inferior quality, can be thus purified by a single operation in the course
of a few days, at an inconsiderable expence. This purification is effected, as
will be hereafter shewn, without causing a boiling or solution of sugar, and-it
has the effect of bringing this inferior produce to the state of purity-and
strength of good clayed sugar, and to render it equally fit for the immediate
making of pure and colourless solution of sugar, or of the finest refined sugar:
According to the usual mode hitherto employed-for-whitening -sugar, it is
covered either with damp clay or with pure and colorless sugar. In both
cases the crystals are repeatedly washed with a solution of pure sugar.
This mode of washing or whitening the sugar necessarily causes a consider-
able quantity of pure sugar to be put into a state of solution; and the
quantity required is enormous, and out of all proportion in claying or purifying
sugars of a low quality. In order to diminish this inconvenience as much
as possible I employ a mode of treatment to which I have given the name
of "Clairçage Continu," or "continued purification," and which I shall here-
after describe. The effect of this continued purification is, to concentrate the
whole of the matters which soil the crystals of the sugar into the smallest
possible solution of sugar.
....
..:*
I will now describe my Improvements in Crystallizing and Purifying Sugar,
as effected by the use of my crystallizing and purifying cases or vessels.
My First Process.-I effect the purification of ordinary raw sugar, or even of
the very lowest description of sugar, in a few days, and almost without expence,
by the use of my purifying vessels or cases (herein-after described by Drawings
and explained by descriptions thereof), without the necessity of
any solution,
clarification, or boiling, but warmed to about twenty degrees of Fahrenheit
under the boiling point of water. I begin with mixing equal quantities of
raw sugar and sugar syrup, or even molasses, which must be mixed as equally
as possible, and then poured into the purifying vessels or cases, and the drain-
ing off of the syrup and molasses through the twisted wire on gauze frame
immediately commences; and even the smallest crystals of sugar remain in
the purifying vessels in the form of a spongy bulk, similar to sugar in the
bastard forms after draining off the syrup. These vessels are placed in the
purifying houses one above another in ranges, as I have shewn in the Drawing
No. 8, and having proper gutters and channels to convey the molasses and
syrup into tanks provided for their reception. When the molasses and syrup
have drained off, which will be in about twenty-four hours, I smooth the
upper surface of the sugar in these vessels, and submit it to my process of
(clairçage continu) or "repeated purification," which consists in pouring upon

page_text: the smoothed surface successive coats or coverings of a saturated solution of
sugar, increasing in purity as the sugar in the vessels becomes more and more
purified and cleansed. from molasses, colouring matter, &c. Thus the first
covering placed on these vessels is such liquor as has already been used four
times in-washing. other sugars; the second covering or purification placed on
these vessels is liquor which has been used three times. previously in washing
other sugars; the third covering placed on the sugar in these vessels, is liquor
which has been twice previously used in washing other sugars; the fourth
covering is liquor which has been used once in, washing other sugars; and the.
fifth and last purification or covering is a solution of pure, sugar,. which has
never been previously used for such process. The liquids resulting from these
washings are collected separately, and are thus employed in future operations.
The first runnings contain the largest portion of, impurity, and must be boiled
to prevent fermentation, and treated as herein-after described; the second
runnings form the first covering for the next quality, of sugar to be operated
on; the third runnings form, the second covering of this sugar; the fourth
runnings form. the third covering of this sugar.; and the fifth runnings are used
for the fourth covering of the second quantity of sugar operated on. And these'
successive operations proceed from day to day as fresh quantities of sugar are,
treated for purification, and the contents, of each vessel or 'case are only once.
covered with a solution of pure sugar, and the result is a complete purification,;
without any waste, of the purified sugar, thus added as the water in which it
was dissolved leaves.it and unites with the molasses, &c., and runs out at the
channel provided for that purpose: The room in which the purifying cases are
put should be constantly charged with damp to a sufficient degree to prevent
any drying of the syrup or the molasses, because that will very much retard
the draining off. If the raw sugar. used is not of a quality inferior to that
called in Paris "quatrième.ordinaire," I can obtain from it, in four or five-
days, seventy-five to eighty.per cent. of pure sugar, equal in quality to clayed
colonial sugar, after deducting the pure sugar used to effect the. " clairçage
continu." The ten or fifteen per cent. of pure sugar, in addition to this which
was contained in the raw sugar previous to this operation, is in a state of solu-
tion in the liquor called first:running, and may be taken from it by the process
hereafter described for obtaining sugar from the solutions. The purified sugar
remaining in these cases comes out crystallized in the form of raw sugar, that
is,, not adhering together, and is then about as dry as lump sugar when taken
out of the form, and can be dried in two days by being put in the air on a

page_text: My Second Process.-In order to draw pure sugar from solutions of sugar,
or from weak and impure syrups so as to form refined sugar, the solutions
of sugar, or the syrups resulting from the process of manufacture which are
not too much exhausted, and which still contain at least one third of crystal-
lizable sugar, should be subjected to concentration by boiling either in vacuo
or in the atmosphere, which, however, should cease when the liquid contains
no more than one equal part of water to three equal parts of sugar and other
matter, a point of concentration which may be easily ascertained by the usual
methods. The weak boiling which is required by my mode of treatment
(never higher than two hundred and thirty-two degrees Fahrenheit) is effected
without turning the syrup brown; in any other manner than by concentration
of the coloring matter already existing in the syrup, and even in boilers, over
an open fire, no torrefaction, or candying, or alteration of the sugar can take
place. The boiling being effected as above, the syrup is treated in the usual
way as to its being cooled (or heated, if boiled in vacuo,) in the cooler, and
then it is stirred up until it becomes a jelly, of the temperature of about one
hundred and ninety degrees Fahrenheit. The ordinary forms or moulds would,
however, be unavailable for filling up with this bulk so weakly boiled, and it
must therefore be filled into my improved crystallizing cases or vessels, the form
and construction of which are herein-after described and explained by Draw-
ings. The filling up into the crystallizing cases being thus finished, the bulk
(by which term "bulk" is meant the boiled crystallized liquor and syrup) is
stirred from time to time with a wooden spatula, of the shape of a large
knife, until it acquires a temperature of 145° Fahrenheit, and it is then left
to crystallize, which generally takes place in twenty-four hours.
When crys-
tallized the cases are taken into the purifying house and arranged and placed
one upon the other, exactly similar to the plan pursued with the purifying
cases, as before stated and shewn in Drawing No. 3. The cases being
arranged the stoppers are taken out and the syrup allowed to drain off as
before, and when drained the crust on the upper surface is to be broken, the
surface smoothed and subjected to the same process of continued purification
as I have described in the previous process when treating raw sugar until the
last running comes out quite pure. The sugar being now purified is turned
out of the boxes by pressing the case at the bottom, and the somewhat moist
and inferior-coloured surface is taken off with a trowel and used for covering,
or put into the case at a future filling to complete its purification. The sugar
when taken out is in the form of a square cake, and will require drying as
before. The sugars produced by these processes are perfectly pure and ready

page_text: for the market in the crushed or disintegrated state, but require a further
process when made into loaves, and in quality is somewhat dependant on the
sugar from which it was manufactured.
From the two processes now described a syrup will result, too much charged
with impurity to be available for the purification of another portion of sugar by
covering, and it must then be boiled without delay so as to prevent fermentation.
Similar syrups, and in general all syrups too much exhausted and too weak to
afford a sufficiently strong crystallization, must be boiled to the candis proof in
order to exhaust them as much as possible of the crystallizable sugar. It would
be absolutely useless, and even prejudicial, to boil such syrups any further, as
they are much more liable to alteration by the action of heat than those
syrups which are most pure and rich in crystallizable sugar. After boiling
these syrups are poured into large impermeable reservoirs of convenient
shape, made of wood or brickwork, or lined with metal, and it is important to
prevent as much as possible the bulk from cooling rapidly, for I have found
that by keeping a temperature of 100° Fahrenheit for a long time, the
formation of strong crystals is much favoured. The crystallization being
finished, the whole bulk, which now forms a mixture of crystals of sugar and
molasses, is put into my purifying cases or vessels, and treated as in the first
process, when the whole of the molasses, &c., percolates through the wire
gauze and is entirely exhausted of its crystallizable sugar, and may be sold.
any
My Third Process.-It now remains to convert the disintegrated sugar pro-
duced by the first or second processes into loaves, which is performed in
manner following:-For forming loaves I dissolve the greater portion of the
pure sugar in pure water, and filter and clarify if necessary, and boil it at the
aforesaid temperature of not exceeding 232° Fahrenheit under atmospheric
pressure, beyond which it must not proceed, and its density is to consist of not
more than three parts of sugar to one part of water. This point of boiling
having been attained, a proper quantity of perfectly pure sugar is added by
small portions to the boiling bulk which is in the boiler, so as to bring it up to
proof by addition of sugar instead of evaporation of the water, stirring it con-
tinually to give the bulk the necessary strength and consistency to form
compact loaves for crystallization. During this process the fire or the steam
should act but slightly on the bulk, but, the mixture being made, it must be
again heated to the point when the first movement of an ebullition begins, and
when it (the bulk) has attained the required strength or consistency the fire
must be put out or the steamcock closed, and the boiler emptied of its
contents into the cooler, and there heated or cooled according to its having
been boiled in open or vacuum boilers, and the usual mode of treating the

page_text: sugar must now be pursued in everything relating to the formation of the
grain by stirring, cooling, and filling up the conical moulds; but the subse-
quent bleaching of the sugar in moulds, if required, must be performed by my
mode of continued purification, and never by the process of claying, and the
liquors or runnings therefrom must be used direct for making refined sugar, or
as covering for sugar in process of purification, according as its quality is clear
or coloured. The liquor having. drained from the loaves, they are, cleaned,
dried, and packed for the market as usual.
The following is a description of the purifying and crystallizing cases, and of
their arrangement in the purifying room herein referred to, and an explana-
tion of the Drawings thereof attached :-
'
Plate No. 1.-The Figures 1 and 2 represent the plan or top view and the
front view of my purifying vessels or cases. Figure 3 represents. a longi-
tudinal section through the line G, G, of Figure 1. Figure 4 represents a
transverse section of Figure 1 through the line H, H. Figure 5. represents
the metallic or other. web, made in this instance of wire. gauze, used for retain-
ing the crystals, and allowing the transmission of molasses and liquors. The
letters in each Figure refer to the same part in every instance; and are
explained as follows:-A is the bottom of the purifying case or vessel, and is
made of wood about three fourths of an inch in thickness, and is covered with
a lining of sheet zine (a), and, which also turns up the sides to the depth of
about one and a half inches. B, B, are the sides of the box, having a slight
inclination, the size of the box being about seventeen and a half inches
square at top, and sixteen and a half inches at the bottom; inside these
are eight inches deep, and five eighths of an inch thick. C, C, are strengthen-
ing fillets of wood, three quarters by two inches, running round the bottom.
of the cases, which also afford facility for putting the cases one on another.
D shews a lip or gutter formed in the zinc lining to carry the syrup to the
funnel E, which receives the same, and discharges it into a gutter or channel,
as shewn in Plate 3. e is a strip of iron rivetted into the funnel E, and
retains the funnel in its position by means of an iron strap f, which is nailed
into the bottom of the box. G, G, shews the handles by which the frames are
moved about; they are attached to the sides by brackets g, g.. I, I, are iron
wire, supports, fixed near the bottom of the purifying case; and over which. the
sieve is laid. K is the metallic web, wire, gauze, or other sieve placed or
streched on the supports I, I, and shewn enlarged in Figure 5,. and which
I prefer to be woven, as shewn in this Drawing. L, L, are iron corner pieces
to strengthen the case; the whole may be painted white. The raw. Muscovado
sugar or molasses is put into this case and supported by the wire gauze K

page_text: which retains the crystal of sugar from leaving the vessel, and allows the
exhausted molasses or sugar syrup to run freely away by the channel D and
funnel E into the gutter or channel shewn in Plate 3, and the syrups used
for washing the sugar in the cases are placed over the smoothed surface of
sugar, and allowed to percolate through, as before described.
Plate No. 2.-The Figure No. 1 represents plan or top view of my crystal-
lizing cases. Figure 2 represents an end view, and No. 3 a side view thereof.
line G; G, and Figure 5
The letters refer to the
Figure 4 shews a section of Figure 1 through the
shews a section of Figure 1 through the line H, H.
same parts in each Figure: The crystallizing vessels I prefer to be of painted
or tinned sheet iron, about No. 14 wire guage in thickness, about seventeen
inches square at bottom, and eighteen inches at top, and having a bottom
slightly inclined from back to front, say half an inch. The depth of these
vessels I prefer to be about eight inches; a band of sheet iron, one-eighth of
an inch thick, is riveted round the top, and frequently round the bottom, also
to increase their durability. The bottom of the front is pierced with about
seven holes, one inch diameter, to allow the syrup to run off, which holes are
marked A, A. These holes are stopped by seven wooden stoppers lettered B, B,
running from front to back of the case across the bottom, tapering from one
inch to half an inch in diameter, and supported at their small ends by a
retain them properly
in a parallel position. The large ends of the plugs project beyond the point
of the case two or three inches, and are finished square to permit being turned
round by a key to loosen them from the crystallized sugar, and allow of
removal. D shews the inclined bottom of case, having a lip E running along
under the holes in the front of the box to collect the syrup, and permit its
dripping into the channel I without the danger of flowing over the bottom
of the case. K shews an iron or wire frame clasping over the top of case,
and suspending the channel or gutter I. G, G, shew the handles of wood,
and g, g, the brackets for securing them to the case, and they are used for
removing the cases. The liquor, after partial concentration and cooling or
heating, as the case may be, is filled into these crystallizing cases, with the
wooden plugs in their places, and when crystallized they are removed from
the boiling to the purifying or draining house, and treated as herein-before
described, by removing the stoppers B, B, to permit drainage, and the sub-
sequent coverings of syrup to complete purification, the syrup from which
runs out at the holes A, A, into the gutter, and is conveyed, as shewn in
Plate 3, to proper réservoirs..
frame C at the back of the case, having small holes c, c, to
Plate No. 3 represents the arrangement of the purifying and crystallization

page_text: vessels when ranged in the draining room; they are shewn placed one above
another, and supported on a wood framework, and having gutters A, A,
running along the front of each set to collect the syrup from the funnels B, B,
of the said cases, and convey it into reserviors C, C, of any convenient size,
from which the syrup is removed and employed according to its purity for
covering other sugars, as before described; but I do not bind myself to
dimensions or materials of manufacture, or to any specific number of coverings
or washings, but I treat the sugar more or less frequently according to its
quality. I therefore claim as the said Invention,-
First, the particular apparatus consisting of my purifying and crystallizing
vessels, as shewn in the Drawings and explained in the description, by means
of which I effect the several processes before described of draining, crystal-
lizing, and purifying sugar.
Secondly, the manual and mechanical process of claircage continue, or
continued purification, by means of washing the sugar contained in the above-
mentioned cases or vessels combined with a metallic other web in the
purifying cases, or in conical forms, with or by continued applications or
coverings of sugar syrup of rather superior quality in each operation to the
sugar under treatment, whereby the most impure sugar is washed consecutively
with better and better coverings or syrup until a solution of pure sugar is used
in the last washing only to complete the process.
Thirdly, the collection of crystalls of sugar from exhausted syrups by
boiling or mixing them with impure sugar so as to bring about a further
crystallization of the sugar remaining in them, and also by boiling very weak
syrups at a very low temperature, and allowing them to stand in large
reservoirs until crystallization has taken place, in combination with the sub-
sequent use of my purifying vessels, whereby the crystals are afterwards
separated and purified by the claircage continue.
Fourthly, the concentration of solution of pure sugar when heated to about
two hundred and thirty Fahrenheit by the addition of a proper quantity of
pure sugar instead of evaporating away the water to produce the said concen-
tration for removing into the water or cooler, as the case may be, and being
then conveyed into the conical moulds in the usual manner.
And such my said Invention being, to the best of my knowledge and belief,
entirely new, and never before used within that part of Her Majesty's United
Kingdom of Great Britain and Ireland called England, Her Dominion of
Wales, and Town of Berwick-upon-Tweed, I do hereby declare this to be my
Specification of the same, and that I do verily believe this my said Specifi-
cation doth comply in all respects, fully and without reserve or disguise, with

page_text: the proviso in the herein-before recited Letters Patent contained; wherefore
I claim to maintain exclusive right and privilege to the said Invention.
In witness whereof, I, the said William Ritter, have hereunto set my
hand and seal, this Tenth day of July, One thousand eight hundred
and forty-three.
AND BE IT REMEMBERED, that on the Tenth day of July, in the year
of our Lord 1843, the aforesaid William Ritter came before our said Lady
the Queen in Her Chancery, and acknowledged the Specification aforesaid,
and all and every thing therein contained and specified, in form above written.
And also the Specification aforesaid was stamped according to the tenor of
the Statute made for that purpose.
Enrolled the Tenth day of July, in the year of our Lord One thousand
eight hundred and forty-three.