IMPROVEMENTS IN THE TREATMENT AND PREPARATION OF SACCHARINE SUBSTANCES, AND IN THE MACHINERY OR APPARATUS CONNECTED THEREWITH
Year: 1853

page_text: LETTERS PATENT to William-Pidding, of the Strand, in the County
of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS
IN THE TREATMENT AND PREPARATION OF
SACCHARINE SUBSTANCES, AND
IN THE MACHINERY OR APPARATUS CONNECTED THEREWITH."
4
Sealed the 5th August 1853, and dated the 17th February 1853.
PROVISIONAL SPECIFICATION left by the said William Pidding
at the Office of the Commissioners of Patents, with his Peti-
tion, on the 17th February 1853.
I, WILLIAM PIDDING, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE TREATMENT AND PREPARATION OF
SACCHARINE SUBSTANCES, AND IN
THEREWITH," to be as follows:-
THE MACHINERY OR APPARATUS CONNECTED
My Invention relates to refining syrups or saccharine juices.
At present this process is effected by a mixture as follows;-
Hydrate of alumina or silica, or a mixture of the two, is thoroughly
[Price 8d.]

page_text: incorporated with a mixture or compound of any of the fatty acids
and resin. To this compound or mixture sometimes small portions
of either of the oxides of iron are added, instead of resin. I propose
to employ bituminous substances. The mixture is incorporated
with a small quantity of water, sufficient only to give it the
consistence of cream, and added by degrees to the syrup, juice, or
liquid, which is carefully heated and co-mixed until that, on taking
out a small quantity and allowing it to deposit, the color and all
impurities are found to be sufficiently removed. It is then placed
in the filter shewn on the Drawing, and evaporated until the syrup
has attained the proper and necessary degree of concentration. 1
also propose to employ, instead of the above-mentioned mixture or
compound, charcoal, whether animal, wood, or vegetable, or coke in
a granular state, or other artificially prepared mixtures containing
carbon, which have been previously saturated with oxygen,
sulphurous acid, hypochlorus acid, or other oxygenous compounds
of chlorine that are obtained in the gazeous state, or avail myself
of the action of both these processes by previously seperating onc
of the mixtures before the employment of the other. In cases of
syrups and aqueous solutions, I employ only carbonaceous compounds
and mixtures, which have been saturated with oxygen or sulphurous
acid. To saturate the carbonaceous substances with the gases is to
make the substances red hot, or nearly so, in a covered vessel; and
when they have cooled (in the case of oxygen) below the point at
which ignition would take place, put the carbonaceous compounds
into vessels filled with such gases as it is intended the substances
should be impregnated with. Mechanical pressure may also be
employed with advantage in some cases, for the purpose of foreing
the gas into the carbonaceous compound.
My filtering vessels are shewn in the accompanying Drawing,
which represents 4 seperate vertical sections of different portions
of my Invention. In Figure 1, A represents the vat or tank in
which is placed the expressed juice, dissolved sugar, or other sac-
charine liquid or matter; B, the first filter. It may be formed of
wood, charcoal, or some such material spread upon the perforated

page_text: floor of the vessel. In this vessel the juice should have but a
small proportion to the temper mixed with it, and should be blown
up by means of a steam pipe to a temperature of about 150
degrees The cloth is hooked at different points outside as shewn
in the Drawing, and in it collected the temper, which is thus
prevented from mixing with the charcoal lying along the portion
B².
When
As soon as this vessel is filled with the juice mixed with a
due proportion of temper, I exhaust the vacuum pan c, by turning
the tap of the pipe leading to the air pump F; I then open
the tap B3, which connects the filter B with the vacuum in C;
rapid filtration ensues. I then open the communication between
the steam boiler and the jacket C³, by opening the tap of the steam
pipe C, and thereby raise the. filtered juice as rapidly as it enters
the vacuum pan C, to the temperature of 150 degrees, by which
means time is saved, and the risk of fermentation prevented.
the vacuum pan C is duly and sufficiently charged, I add a proper
quantity of temper by turning the tap of the vessel C', which is
drawn in by atmospheric pressure outside. I append a small glass
tube and piston C², outside the vacuum pan C, by means of which
a portion of the juice may be brought up at any time to test its
color. As soon as the color appears to be removed, I let in the
atmospheric pressure by opening the tap C', and allow of the syrup
passing into the second filter D, by opening the tap Co.
The second
filter is composed of animal charcoal, and provided with a cloth, as
already described, to prevent the mixing of the temper with the
charcoal. I find it advisable to place a cloth on the perforated
floor of both filters, in order that the charcoal, &c. may be removed
rapidly, and also to prevent any portion of it from finding its way
into the pans below. These cloths should also be fastened or hooked
to the outside or top of the vessel. The hooking loops may be
brought together, and both the temper and charcoal removed
mechanically by a small crane or otherwise." I hasten the filtration
in D, by a similar process to that I have just described; viz., by
exhausting the pan E, by turning the tap F¹, in connexion with the

page_text: air pump F²; I turn on the steam tap E, immediately after the com-
mencement of the filtration; I boil the syrup in this pan to the
consistence necessary for loafing, which I test by a test stick, as shewn
in the Drawing. I then cause the steam with a small quantity of
sugar to be absorbed into a condensor, in which the sugar is saved
and collected by means of the air pump F'. Both the up and down
strokes of the piston may be rendered. available by turning the tap
F', and a more rapid rate of exhaustion thereby effected.
In large
works I recommend the adoption of a double range of filters and
pans, as shewn in Figure 4, by which means the juice can be worked
as rapidly as it is produced by the mill. Figure
Figure 2, represents a
vertical and longitudinal section, and Figure 3, a vertical and trans-
verse section of the loafing apparatus.. In it the loaf moulds are
shewn screwed into their lower frame B, and made air tight by
collars of vulcanized india-rubber B2. The frame B consists of a
pipe of a triangular cross section, and communicating at one end
with the air from within the spaces of the moulds.
This pipe also
a reservoir in
conducts the sugar drained from the loaves into
connexion with the pipe B³. The upper end of the moulds fit into
a trough C, which have a circle of vulcanized india-rubber round the
apertures to prevent the syrup falling through, and I use a pressure of
one or more atmospheres to facilitate the operation of the vacuum.
The moulds with sugar and syrup allowing the latter to be drawn
into the pipe B', and from thence into the reservoir in connexion
with B³, I keep adding syrup in the trough, till such time as the
sugar has all coloured syrup removed from it.
SPECIFICATION in pursuance of the conditions of the Letters
Patent, filed by the said William Pidding in the Great Seal
Patent Office on the 16th August 1853.
. TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
WILLIAM PIDDING, of the Strand, in the County of Middlesex,
Gentleman, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent, bearing date the Seventeenth day of February,
One thousand eight hundred and fifty-three, in the sixteenth year
of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said William Pidding, Her especial license that I,
the said William Pidding, my executors, administrators, and assigns,
or such others as I, the said William Pidding, 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, my Invention of
"IMPROVEMENTS IN THE TREATMENT AND PREPARATION OF SACCHARINE
SUBSTANCES, AND IN THE MACHINERY OR APPARATUS CONNECTED THEREWITH,"
upon the condition (amongst others) that I, the said William Pidding,.
by an instrument in writing under my hand and seal, should
particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the
same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said William Pidding, 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):
I will first allude to the articles and commixture of articles or
substances I use in my improvements, and afterwards describe the
apparatus used in effecting or carrying out my Invention.
I take a quantity of hydrate of alumina prepared from the
sulphate, or by any other convenient process, and having well
washed and drained it, so that it shall be quite stiff, I mix with it
a quantity of powdered black rosin, or resin, or colophony, (prepared
as herein-after described,) in the proportion of the quantity of dry
alumina which is contained in the hydrate (that is, about eighteen

page_text: per cent.); mix the rosin and hydrate of alumina intimately together,
and bring them to the consistence of cream by the means or addition
of water. I have found that precipitated silica will answer the pur-
pose of hydrate of alumina; but I do not confine myself to either of the
above substances, as I use animal or vegetable pitch or tar, the re-
sins commonly called gum resins (prepared as herein-after described)
mixed in the proportion above stated with hydrate of alumina or selica.
I have also found that a mixture of margaric acid, oleic acid,
stearine, spermacetti, or wax, mixed in the proportion above stated,
and prepared in the manner herein-after described, with hydrate of
alumina or silica, answer the purpose equally well. I have also
sometimes found it advisable, when I have required to reduce the
melting point of rosin, which is 140°, to mix a small quantity of
lard or other grease, margaric or oleic acid, or wax, (prepared as
herein-after described,) with the rosin, which reduces its melting
point to about 110°. In some cases advantage is derived from
mixing a slight quantity of hydrated oxide of iron to the alumina
and rosin, or other substance, as in some instances some of the
coloring matters contained in sugar arise from a small portion of
tannin. I have also found the addition of a little acetic acid useful,
after the use of any of the former substances, though in general the
use of free acids is objectionable.
I will now proceed to describe the method of defication, and the
apparatus for so doing. The sugar having been brought up to the
temperature of 120°-130°, in the first pan C, I.add the alumina and
resin (or any of the other substances before described) in the con-
sistence of a thin cream. The temper should be introduced low
down in the pan by a pipe for that purpose; the sugar should be
kept stirred during the addition of the temper. When the stirring
has been kept up for a sufficient time, which the color of the sugar
will show, the temper must be allowed to rise to the top, when it
will be found the sugar has lost most of its color.
If the process
be conducted with care, the solution of sugar will be of a very pale
sherry color. The quantity of the temper to be used depends on

page_text: the color of the sugar in the first instance, and must be re-
gulated as experience shall shew. The cock of the upper pan
may now be opened, and the sugar passed into the filter D,
the bottom of which is strewed or piled with animal charcoal
resting on perforated iron plates (a 1); the temper is prevented
mixing with the charcoal by means of a coarse cloth. As soon as
the bottom of the filter is covered with the sugar, the cock
D', connecting the filter with the vacuum pan must be opened,
and the pressure of the air caused by the vacuum pressing on
the solution will cause it rapidly to pass through the bed of
charcoal; care must be taken that, on opening the cock between the
upper pan and the filter, the rush of syrup does not displace the
charcoal; if well managed, the temper cloth will prevent that
accident. The syrup is then to be boiled in the vacuum pan in the
usual way.
The arrangement of the filter and vacuum pan may be
varied as experience shall dictate. By the above process time is
saved, and consequently the chance of decomposition of the sugar.
Another part of my Invention consists in the treatment of the
sugar after it is crystalized, and before it is removed into the loaf
moulds. Immediately the sugar has arrived at the proper state of
crystelization, the slide (a) is removed, and a jet of steam intro-
duced at the end of the pipe (b), as is well understood. A vacuum
is formed, which hastens the removal of the residual syrup in the
crystalized mass in the pan; a little clean syrup should be added
at the top of the pan, and allowed to be sucked through the mass
by the vacuum caused by the jet. An air pump or large pan is
equally applicable for this purpose. When the crystaline mass is
drained, it may be placed in moulds (A, B 2); the moulds being
also acted upon by vacuum, caused by a steam jet or air pump, to
facilitate the removal of the residual syrup.
Another portion of my Invention consists in the treatment of the
temper after it has been used for deficating purposes.
The temper
is first placed in a trough provided with stirrers; it is then well
heated and washed by means of water kept hot by steam jets, the

page_text: stirrers keeping the temper constantly in motion. When sufficiently
washed, it is to be removed, dried in a steam pan, and melted by
steam heated by passing through hot pipes, then left to cool, and
powdered. In this state, it is very useful to mix with fresh temper
for the purposes before described. In some cases I have found it
useful to use a little sulphurous or acetic acid in the water in which
it is washed, in order to remove all taste and odour. The rosin,
animal or vegetable tar or pitch, margaric or oleic acid, wax,
stearine, spermaceti, or grease, must be placed in an iron vessel,
and kept boiling by means of steam jets; clear hot water should be
constantly. kept flowing into the vessel, and the waste water carried
off. The water must be kept in motion during the operation; the
process should be continued as long as any odour or taste is imparted
by the substances to the water. The substances are then dried and
carefully melted, when desirable or necessary, powdered, and are
then fit for use.
Having now described the nature of my Invention, and the means
by which the same may be carried into practical effect for the
purpose of defication of sugar or sacharine matters generally, I
claim for such purposes,-
Firstly, the use of bituminous substances (that is to say),
animal or vegetable tar or pitch, margaric, oleic, or fat acids, wax,
stearine, spermacitti, and greases prepared in the manner described;
the resins usually called gum resin, rosin, or colophony, when
combined with the hydrate of alumina, precipitated silica, or oxide
of iron.
Secondly, the combination of margarric acid, wax, and grease,
prepared as herein-before described with rosin, previous to its ad-
mixture with hydrate of alumina, silica, or oxide of iron, for the
foregoing purposes.
Thirdly, the combination of the vacuum pan and the filter, as
shewn (in the annexed Drawing), by means of which much labor
and loss of time is saved.
Fourthly, the treatment, as herein-before described, of sugar after

page_text: crystalization, by drawing off the residual syrup by means of
vacuum, both before and after it is placed in moulds.
In witness whereof, I, the said William Pidding, have hereunto
set my hand and seal, this Sixteenth day of August, in the
year of our Lord One thousand eight hundred and fifty-
three.
Witness,
JAMES PIDDING,
3, Crown Court,
Threadneedle Street.
W. PIDDING. (L..S.)