IMPROVEMENTS IN APPARATUS FOR THE MANUFACTURE OF SULPHATE OF SODA AND SULPHATE OF POTASH
Year: 1874

page_text: LETTERS PATENT to William Hunt, of Castleford, near Normanton,
in the County of York, Manufacturing Chemist, for the Invention
of "IMPROVEMENTS IN APPARATUS FOR THE MANUFACTURE OF SULPHATE OF
SODA AND SULPHATE OF POTASH."
Sealed the 10th November 1875, and dated the 2nd September 1874.
PROVISIONAL SPECIFICATION left by the said William Hunt at the
Office of the Commissioners of Patents, with his Petition, on the
2nd September 1874.
I, WILLIAM HUNT, of Castleford, near Normanton, in the County of
6 York, Manufacturing Chemist, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN APPARATUS FOR THE MANUFACTURE OF SULPHATE
OF SODA AND SULPHATE OF POTASH," to be as follows:-.
My Invention has reference to that process of manufacturing sulphate
of soda and sulphate of potash, in which chloride of sodium or chloride
of potassium is placed in chambers and operated upon and decomposed
by a mixture of sulphurous acid gas, air, and steam passed through the

page_text: said chambers. The result of the decomposition is sulphate of soda or
sulphate of potash and hydrochloric acid gas.
In conducting the said process it is important that the apparatus and
materials should be kept at a high temperature, and in order that the
gaseous mixture should enter the chambers at the requisite high
temperature the pyrites' burners in which the sulphurous acid gas is
produced are usually placed as near as is convenient to the chambers.
The arrangements of the apparatus hitherto adopted have not however
prevented the loss of a large amount of the heat produced in the pyrites'
burners, and the object of my Invention is so to construct and arrange
the apparatus that the heat of the pyrites' burners shall be economized
to a much greater extent than heretofore.
My Invention consists in constructing and arranging the apparatus
for the said manufacture of sulphate of soda and sulphate of potash in
the following manner:-I erect the chambers in which the chloride of
sodium or potassium is to be decomposed immediately over the pyrites'
burners, two or three or other number of the said pyrites' burners being
situated under each of the said chambers. The hot gases from the said
burners pass out through the arches of the burners and travel under and
in contact with the floors of the chambers. The hot gases from the
burners, with the required admixture of air and steam, pass. into the
first chamber of the series at the bottom of the said chamber, rising up
the said chamber and passing out at its top and entering the top of the
second chamber, in which it descends, passing out at the bottom, and
entering the bottom of the third chamber ascends, and so on through
the series.
By my Invention the bottoms of the chambers are maintained at a
high temperature, which is communicated to the gaseous mixture as it
circulates through the chambers.
I construct the bottoms of the chambers either of iron plates or of
arches of brickwork built on the walls, by which the pyrites' burners are
separated from each other.
By the use of my Invention the heat produced by the burning of the
pyrites is ordinarily sufficient to maintain the required temperature
throughout the apparatus.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Hunt in the Great Seal Patent Office on
the 24th February 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
HUNT, of Castleford, near Normanton, in the County of York, Manu-
facturing Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Second day of September, in the year of our
Lord One thousand eight hundred and seventy-four, in the thirty-eighth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said William Hunt, Her special licence that I, the
said William Hunt, my executors, administrators, and assigns, or such
others as I, the said William Hunt, 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 Invention for "IMPROVEMENTS IN APPARATUS FOR THE
MANUFACTURE OF SULPHATE OF SODA AND SULPHATE OF POTASH," upon the
condition (amongst others) that I, the said William Hunt, mỹ
executors or administrators, by an instrument in writing under
my, or their, or one of their hands and scals, 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 Hunt, 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 thereof, that is to say:
1
My Invention has reference to that process of manufacturing sulphate
of soda and sulphate of potash, in which chloride of sodium or chloride
of potassium is placed in chambers and operated upon and decomposed
by a mixture of sulphurous acid gas, air, and steam passed through the
:

page_text: said chambers. The result of the decomposition is sulphate of soda or
sulphate of potash and hydrochloric acid gas.
In conducting the said process it is important that the apparatus and
materials should be kept at a high temperature, and in order that the
gaseous mixture should enter the chambers at the requisite high
temperature the pyrites' burners in which the sulphurous acid gas is
produced are usually placed as near as is convenient to the chambers.
The arrangements of the apparatus hitherto adopted have not however
prevented the loss of a large amount of the heat produced in the pyrites'
burners, and the object of my Invention is so to construct and arrange
the apparatus that the heat of the pyrites' burners shall be economized
to a much greater extent than hicretofore.
My Invention consists in constructing and arranging the apparatus
for the said manufacture of sulphate of soda and sulphate of potash in
the following manner :-I erect the chambers in which the chloride of
sodium or potassium is to be decomposed immediately over the pyrites'
burners, two or three or other number of the said pyrites' burners being
situated under cach of the said chambers. The hot gases from the said
chambers pass out through the arches of the burners and travel under
and in contact with the floors of the chambers. The hot gases from the
burners, with the required admixture of air and steam, pass into the
first chamber of the series at the bottom of the said chamber, rising up
the said chamber and passing out at its top and entering the top of the
second chamber, in which it descends, passing out at the bottom, and
entering the bottom of the third chamber ascends, and so on through
the series.

page_text: Figure 1 of the accompanying Drawings represents in vertical section
an apparatus constructed according to my Invention. Figure 2 also
represents a vertical section of the same. Figures 3 and 4 represent
side elevations of the same, and Figure 5 represents a plan of the same.
The section, Figure 1, is taken on the line A, B, Figure 5: The section,
Figure 2, is taken on the line C, D, Figure 5. The elevation, Figure 3,
is taken at the side E, Figure 5; and the elevation, Figure 4, is taken
at the sido F, Figure 5. The same letters of reference indicate the same
parts.
a, a, are the pyrites' burners, situated, as represented, under the
chambers d, d, containing the chloride to be operated upon. The
sulphurous acid gas produced in the burners a, a, passes through openings
a², a, in the arched tops of the said burners a, a, into the channels c,
which run underneath the whole series of chambers d, d. The top c² of
the channels c is made of plates of cast iron or other good conductor of
heat; d² is the perforated or reticulated bottom of the chamber d, on
which bottom the chloride to be operated upon rests. The said perforated
bottom d is supported on columns or supports not represented in the
Drawing, which supports rest upon the cast-iron plates c². The cast-iron
plates become strongly heated by the gases as they issue from the
burners a, and as the gaseous current passes into or out of the chambers d
by the perforated bottoms d² the said gaseous current becomes strongly
heated by contact with the cast-iron plates c².
In order to supplement the heat of the pyrites' burners independent
fire-places may be placed underneath the chambers and beside a group or
series of pyrites' burners in the manner illustrated in Figures 3 and 5
in which Figures the independent fire-places are marked f.
I have not thought it necessary to describe and represent the direction
in which the gaseous current passes through the chambers d, d, nor do I
think it necessary to describe the manner in which the several chambers
are charged and discharged, as these things constitute no part of my
present Invention.
Having now described the nature of my Invention, and the manner
in which the same is to be performed, I wish it to be understood that I
do not limit myself to the precise details herein described and illustrated,
as the same may be varied without departing from the nature of my
Invention; but I claim as my Invention the improvements in apparatus

page_text: to be employed in the manufacture of sulphate of soda and sulphate of
potash; herein-before described and illustrated in the accompanying
Drawings, that is to say, constructing or arranging the chambers in
which the decomposition of the chloride of sodium or potassium is
effected immediately over the pyrites' burners in which the sulphurous
acid gas is produced, substantially as described and illustrated, whereby
the heat of the said burners is economized in the most effectual manner
for maintaining the necessary high temperature of the gaseous current
passing through the decomposing chambers, whether the heat of the said
pyrites burners is or is not supplemented by the heat of independent
fires or furnaces.
In witness whereof, I, the said William Hunt, have hereunto
set my hand and seal, this Nineteenth day of February, in the
year of our Lord One thousand eight hundred and seventy-
five.
Witness,
THO. H. GORLE,
Castleford,
near Normanton.
WILLIAM HUNT. (L.S.)