A NEW METHOD OF PURIFYING SOLUTIONS
Year: 1869

page_text: LETTERS PATENT to William Robert Lake, of the "International
Patent Office," No. 8, Southampton Buildings, London, Consulting
Engineer, for the Invention of "A NEW METHOD OF PURIFYING SOLUTIONS
Sealed the 1st March 1870, and dated the 22nd September 1869.
PROVISIONAL SPECIFICATION left by the said William Robert Lake
at the Office of the Commissioners of Patents, with his Petition,
on the 22nd September 1869.
I, WILLIAM ROBERT LAKE, of the "International Patent Office,"
No. 8, Southampton Buildings, London, Consulting Engineer, do hereby
declare the nature of the said Invention for "A NEW METHOD OF PURIFYING
SOLUTIONS OF SUGAR AND SYRUPS, AND IN APPARATUS THEREFOR," a communi-
cation, to be as follows:-
The application of sulphurous acid in a liquid or gaseous form or state
for bleaching juices has been tried, but it could not be carried into
practice upon a large scale because with the employment or application
[Price 8d.]

page_text: of sulphurous acid was connected the production of sugar of grapes; on
the other hand the bad taste of the sugar and of the syrup caused by
this process could not be avoided, they still contained free sulphurous
acid. I have ascertained that if juices are worked with a solution of
sulphurous acid in water, which solution contains no more that 1 or
1 per cent. of sulphurous acid, no sugar of grapes is produced, and
that after the water is evaporated there will remain no taste of
sulphurous acid, also if 100 parts of solution of sugar of from 36° to
42° B. are mixed with from 8 to 10 parts of a solution of 1 part
sulphurous acid and 100 parts of water, and the whole then thickened
to the consistency of syrup all the sulphurous acid is evaporated. The
sugar solution is dissolved and the taste of it is much better than when
large quantities of animal charcoal are used. The disagreeable taste of
beetroot in the beetroot sugar solutions is eliminated completely. In
the solutions of the beetroot sugar and of all coarse sugars which contain
lime and alkali the latter are neutralized and the noxious influence of
the alkalis upon the crystalization is avoided. The solution of
sulphurous acid can also be applied to diluted solutions of sugar. The
mixture of the sugar solution with one part of sulphurous acid in 100
parts of water is either made in a mixing vessel and the whole is then
evaporated in the vacuum pan or in the open air, or the solution is
drawn directly into the vacuum pan; after this is filled to % of its
ordinary contents with the sugar solution to be boiled and purifyied the
drawing in of the solution is then effected simultaneously with the
drawing in of the sugar solution to be evaporated.
A characteristic feature of my Invention consists in the apparatus,
which permits of the preparation from ordinary sulphur at all times of
a uniform solution containing one part of sulphurous acid and 100 parts
of water. The furnace for doing this consists of a burning chamber or
pan, a refrigerating tube and a vessel in which the sulphurous acid is
absorbed by water. The quantity of burned sulphur in a given time
under the influence of a given quantity of air is always the same so
long as the furnace, the time, and the air are the same. The stream of
air to the furnace is regulated by an injector and valves.
If at every
minute the same quantity of sulphur is burned it is only necessary to
lead a uniform stream of cold water into the absorbing vessel for getting
a uniform solution of sulphurous acid and water. This stream of cold
water is regulated by a suitable apparatus constructed for the purpose.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Robert Lake in the Great Seal Patent
Office on the 22nd March 1870. .
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROBERT LAKE, of the "International Patent Office," No. S, South-
ampton Buildings, London, Consulting Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-second day of September, in the
year of our Lord One thousand eight hundred and sixty-nine, in the
thirty-third year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said William Robert Lake, Her
special licence, that 1, the said William Robert Lake, my executors.
administrators, and assigns, or such others as 1, the said William
Robert Lake, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an In-
vention for "A NEW METHOD OF PURIFYING SOLUTIONS OF SUGAR AND SYRUPS,
AND IN APPARATUS THEREFOR," a communication to me from abroad by
August Seyferth, of the City of Brunswick, Germany, upon the condition
(amongst others) that I, the said William Robert Lake, my executors or
administrators, by an instrument in writing under my, or their, or one of
their hands and seals, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said William Robert Lake, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in
and by the following statement, reference being had to the accompanying
Drawing forming a part of this Specification:-
Sulphurous acid has often been applied in both a liquid and gaseous
condition to bleach juices of sugar, but it has never been introduced
directly in the vacuum pan and mixed in this apparatus with the
solution of sugar, treacle, or molasses to be boiled. By my Invention

page_text: the juices of sugar are worked directly in the vacuum pan either with a
solution of sulphurous acid in water which does not contain more than
1 or 14% sulphurous acid or of the gas of sulphurous acid. I mix in
the vacuum pan 100 parts of a concentrated solution of sugar of 28 to
42° B. and 3 to 15 parts of a solution of sulphurous acid containing
100 parts of water of 1 to 1 part gaseous sulphurous acid. I then
thicken the mixture to the ordinary concentration of boiled sugar masses.
During the evaporation of the sulphurous acid is completely evaporated.
The juices are improved in taste in a way which cannot be obtained by
applying great quantities of animal charcoal. The disagreeable taste of
the beetroots is completely removed from solutions of beetroot sugar.
The alkalis of beetroot sugar solutions and salts of coarse sugar con-
taining alkalis are neutralized and their noxious influence on the
crystalization of the sugar is prevented. The solutions of sulphurous acid
can also be applied to diluted solutions of sugar. The solution of sulphurous
acid or the gas is introduced in the lower end of the vacuum pan Z,
(Figure 5) that it may be well mixed with the masses to be boiled before
it is evaporated and taken off by the air pump. The quantity of acid
wanted for a certain solution of sugar or molasses can be easily
ascertained by trial. The trials can be made on the vacuum pan. The
clear color of the boiling sugar masses shows with certainty whether the
solution has been worked sufliciently by acid or not.
A part of my Invention is the apparatus which allows the production
from coarse brimstone of a uniform solution of sulphurous acid in water.
The apparatus herein-after described can be modified essentially, but an
important feature of my Invention is the possibility of conducting a
uniform equal quantity of water into the condensing apparatus
corresponding to the quantity of brimstone burnt.
The apparatus for the combustion of the sulphur consists of a flat
cup A, Figure 1, which is fastened to the cap B, the latter has 3
openings, the one L is connected by screws with neck N fitted at O
with a stop-cock which regulates the entrance of the air. The door M
serves for introducing the sulphur; this door can be closed and made
air-tight by a set screw. The cooling apparatus C consists of a cast-
iron tube C, and the casing C in the intermediate space is the water
for cooling. At is a stump to which a tube can be fitted which carries
the warm water away; the cold water is conveyed through the tube I.
The condenser D, Figure 2, consists of a vessel of lead placed in a
wooden case. In the condenser is a large number of horizontal channels

page_text: of lead, over which the stream of sulphurous acid is conducted by vertical
partitions. The absorbing water flows in an opposite direction to the
sulphurous acid. In the lower part of the case space is allowed for
accumulating a larger quantity of liquid sulphurous acid. The U-shaped
tube is connected with this part of the case, and is fitted at its end
with an india-rubber tube which leads into a reservoir.
In the upper
bent portion of the tube S is an opening, which can be closed by a small
stopper of wood; this opening is not closed when the apparatus is at
work. The gases of combustion are discharged by a tube of lead of
about 2 inches diameter into a chimney. The velocity of the gases in
the furnace must not be too high, but the draught in the furnace must
be so strong that the combustion of sulphur is continuous.
It is
necessary to regulate either by a stop-cock or by a diaphragm the mote-
ment of the air in the apparatus. The supply of the water is regulated
through a regulator E'; this regulator consists of a separate vessel,
Figures 3 and 4, in which the water flows through the sieve c coming
from a water pipe. The vessel has at e, d, f, g, h, i, openings, one of
which is fitted permanently with an india-rubber tube which conducts
the overflowing water to the funnel; the others are closed by stoppers.
At each opening is indicated how many pounds of sulphur may be
burnt in the vessel A in 24 hours if the water level in the stream
regulator is regulated by this opening, so that a sufficient quantity of
water passes the apparatus. The water flows through the openings k in
the funnel m which fits in the inlet opening of the condensor. The
water coming out of the india-rubber tube of the stream regulator enters
through the tube I in the cooling apparatus C. The sulphurous acid
produced passes through the tube S and through an india-rubber tube
into a tank which may be a petroleum barrel, or a wooden case lined
with lead.
In commencing to work the apparatus a wood or coal fire is lighted
and brimstone is put in the vessel A; a stream of water is then drawn
through the regulator into the condenser corresponding to No. 40 on
the regulator. The burning of the sulphur is regulated in order that
the air stream will not be too violent but will be such that the products
of combustion are cooled sufficiently by means of the cooler and that
the liquid discharged at S has not a higher temperature than 28 to 30°
Celsius. Instead of a solution of sulphurous acid I may use sulphurous
acid gas which is produced by burning brimstone in a stove. The
vacuum apparatus is connected with the upper part of the stove and the
-

page_text: combustion gases are heated directly in the boiling sugar solution. The
gas can be washed in a tank by water, which can be renewed by a
regulator. Figure 5 shews this apparatus. R is the stove; S, the door
for the introduction of sulphur; T, a washing tank with pipe V for the
introduction of water, which is regulated by the regulator W; Y is the
pipe for conducting the gas to the vacuum pan Z; N is the pipe for the
introduction of the solution of acid or the gas into the vacuum pan.
Instead of sulphurous acid I can apply a solution of hydrosulphurous
acid which is produced by the action of zinc or other water decomposing
metal on a solution of sulphurous acid. This solution is prepared in a
barrel filled with pieces of zinc (or other water decomposing metal).
The solution of sulphurous acid is introduced in this barrel and rests on
the metal for from ten to fifteen minutes, then it is thrown directly into
the evaporating apparatus as above described. The solution of hydro-
sulphurous acid loses the decolorizing power if it remains longer on the
metal or if brought in contact with the oxygen of the atmosphere.
In witness whereof, I, the said William Robert Lake, have here-
unto set my hand and seal, this Twenty-second day of March,
in the year of our Lord One thousand eight hundred and
seventy.
WILLIAM ROBERT LAKE. (L.S.)
Witness,
HARRY WRAIGHT,
Clerk to Messrs. Haseltine, Lake, & Co.