IMPROVEMENTS IN THE MANUFACTURE OF SULPHATES OF SODA
Year: 1870

page_text: LETTERS PATENT to James Hargreaves, of Appleton-within-Widues,
in the County of Lancaster, Analytical Chemist, and Thomas
Robinson, of Widnes, in the same County, Ironfounder, for the
Invention of
"
DA "
IMPROVEMENTS IN THE MANUFACTURE OF SULPHATES OF SODA
Scaled the 19th May 1871, and dated the 21st November 1870.
PROVISIONAL SPECIFICATION left by the said James Hargreaves
and Thomas Robinson at the Office of the Commissioners of Patents,
with their Petition, on the 21st November 1870.
We, JAMES HARGREAVES, of Appleton-within-Widnes, in the County
of Lancaster, Analytical Chemist, and THOMAS ROBINSON, of Widnes, in
in the same County, Ironfounder, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF SULPHATES OF SODA
AND POTASSA," to be as follows:-
Our Invention relates to improvements in or upon that method or
process of manufacturing sulphate of soda and sulphate of potassa by
passing currents of mixed sulphurous acid, air, and water vapour, prefer-

page_text: ably heated, through or amongst heated chloride of sodium and chloride
of potassium for which we obtained Royal Letters Patent bearing the
serial number 46 of the year 1870, and consists,-
First. As means for obtaining increased effect in the production of
sulphates from a given quantity of sulphurous acid gas mixed with air
and water vapour we employ the said sulphurous acid gas, air, and
water vapour in about the following proportions, to every two volumes
of sulphurous acid gas we add two volumes of water vapour and air in
sufficient quantity to furnish one volume of free oxygen.
Second. As means for providing an increased surface of chloride of
sodium or chloride of potassium for the action of the mixed sulphurous
acid gas, air, and water vapour thereon when in the chambers or vessels,
and at the same time leaving free passages for the currents of mixed
sulphurous acid gas, air, and water vapour we use the said chloride of
sodium or chloride of potassium in pieces containing preferably cach
about three-quarters of a cubic inches. We form the pieces by breaking
rock salt, or by moistening, pressing, drying, and breaking salt which is
in powder or small crystals, or we use bay salt with crystals of the size
mentioned. When chloride of potassium has to be prepared the
treatment just mentioned for chloride of sodium is followed.
Third. As means for causing the currents of sulphurous acid gas,
air, and water vapour to act uniformly on the mass of chloride of sodium
or chloride of potassium in the chambers, and for preventing the said
currents from passing rapidly up the sides of the chambers we place
the pieces of smaller size at and near to the sides of the chambers.
Fourth. As means for fully utilizing the sulphurous acid gas in the
mixture of the same with air and water vapour, and at the same time
converting the whole of the chlorides into sulphates, we pass the mixture
of sulphurous acid gas, air, and water vapour together with any hydro-
chloric acid given off in succession through two or more vessels or
chambers containing the chloride of sodium or chloride of potassium.
Mifth. As means for rendering the production of sulphate of soda or
sulphate of potassium continuous, we use a scries preferring not less
than four chambers. When four chambers are used the gas is admitted
into No. 1 and passes through Nos. 2, 3, and 4, escaping at the latter.
When the formation of sulphate is completed in No. 1 the mixture of
sulphurous acid gas, air, and water vapour is admitted first to No. 2 and
then to Nos. 3 and 4, afterwards when No. 1 is recharged also to and

page_text: through it. The chambers therefore alternately become the first, inter-
mediate, and last of the series; the mixed sulphurous acid gas, air, and
water vapour it will thus be obvious pass first into the chamber in which
the material is most nearly converted into sulphate, and the hydrochloric
acid formed together with any other gases passes away from the chamber
last charged with chloride to the condensing towers.
Sixth. As an alternative method of rendering the production of
sulphates continuous we employ a tower or chamber of considerable
height to contain chloride of sodium or chloride of potassium, and we
pass the current of mixed sulphurous acid gas, air, and water, upwards
through the mass. When the lower portion of the chloride is converted
into sulphate it is withdrawn and fresh chloride added at the top.
•
Application is made simultaneously with this for Provisional Pro-
tection for the apparatus alluded to herein, and to be employed in the
manufacture above described by us No. 3047, and bearing date
November 21, 1870.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Hargreaves and Thomas Robinson in the
Great Seal Patent Office on the 20th May 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JAMES
HARGREAVES, of Appleton-within-Widnes, in the County of Lancaster,
Analytical Chemist, and THOMAS ROBINSON, of Widnes, in the same
County, Ironfounder, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of November, in the
year of our Lord One thousand eight hundred and seventy, in the
thirty-fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said James Hargreaves and Thomas
Robinson, Her special license that we, the said James Hargreaves and
Thomas Robinson, our exccutors, administrators, and assigns, or such
others as we, the said James Hargreaves, and Thomas Robinson, our
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
:

page_text: Ireland, the Channel Islands, and Isle of Man, an Invention for "IM-
PROVEMENTS IN THE MANUFACTURE OF SULPHATES OF SODA AND POTASSA," upon
the condition (amongst others) that we, the said James Hargreaves and
Thomas Robinson, our executors or administrators, by an instrument
in writing under our, or their, or one of our or 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 Scal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that we, the said James Hargreaves and Thomas
Robinson, do hereby declare the nature of our 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:-
Our Invention relates to improvements in or upon that method or
process of manufacturing sulphate of soda and sulphate of potassa by
passing currents of mixed sulphurous acid, air, and water vapour, pre-
ferably heated through or amongst heated chloride of sodium and chloride
of potassium for which we obtained Royal Letters Patent bearing the
serial number 46 of the year 1870, and consists,―
First. As means for obtaining increased effect in the production of
sulphates from a given quantity of sulphurous acid gas mixed with air
and water vapour, we employ the said sulphurous acid gas, air, and
water vapour in about the following proportions, to every two volumes
of sulphurous acid gas we add two volumes of water vapour and air in
sufficient quantity to furnish one volume of free oxygen.
In practice we find that the air which passes through ordinary pyrites,
or sulphur burners with the sulphurous acid gas, contains sufficient
free oxygen to combine with the sulphurous acid and form sulphuric
acid.
Second. As means for providing an increased surface of chloride of
sodium or chloride of potassium, for the action of the mixed sulphurous
acid gas, air, and water vapour thereon when in the chambers or vessels, and
at the same time leaving free passages for the currents of mixed sulphurous
acid gas, air, and water vapour. We use the said chloride of sodium or
chloride of potassium in pieces, containing each about three-quarters
of a cubic inch. We form the pieces by breaking rock salt, or by
moistening, pressing, drying, and breaking salt, which is in powder

page_text: or small crystals; or we use bay salt with crystals of the size mentioned.
When chloride of potassium has to be prepared, the treatment just
mentioned for chloride of sodium is followed.
We would have it understood that we do not claim the forming and
breaking of the pieces, as this part of our Invention consists only
in the use of the chlorides in pieces of about the size named.
Third. As means for causing the currents of sulphurous acid gas, air,
and water vapour, to act uniformly on the mass of chloride of sodium
or chloride of potassium in the chambers, and for preventing the said
currents from passing rapidly up the sides of the chambers, we place the
pieces of smaller size at or near to the sides of the chambers.
A convenient method of obtaining chlorides in picces of small size,
in admixture with a mass of pieces of about the size mentioned under
the above second part, consists in breaking large blocks of rock, stove
dried, or other salt by stampers or other appliances, and a convenient
method of causing the small pieces to pack or remain at the sides or
inner surfaces of the chambers consists in pouring or filling the chlorides
into the chambers from the top at or near the sides or inner surfaces;
in this way the smaller pieces remain at the sides, whilst the larger pieces
roll towards or pack in the middle.
Fourth. As means for fully utilizing the sulphurous acid gas in the
mixture of the same with air and water vapour, and at the same time
converting the whole of the chlorides into sulphates, we pass the mixture
of sulphurous acid gas, air, and water vapour together with any hydro-
chloric acid given off in succession through two or more chambers
containing the chloride of sodium or chloride of potassium, that is to say,
through the mass of chloride contained in one chamber, thence through
the chloride contained in a second chamber, or a larger number than two
may be used.
Fifth. As means for rendering the production of sulphate of soda or
sulphate of potassa continuous, we use a series, preferring not less than
four, of chambers. When four chambers are used the gas is admitted
into No. 1, and passes through Nos. 2, 3, and 4, escaping at the latter.
When the formation of sulphate is completed in No. 1, the mixture of
sulphurous acid gas, air, and water vapour is then admitted first to No. 2;
and then to Nos. 3 and 4; afterwards when No. 1 is recharged also to
and through it. The chambers therefore alternately become the first,

page_text: intermediate, and last of the series. The mixed sulphurous acid gas, air,
and water vapour it will thus be obvious pass in ordinary working first
into the chamber in which the material is most nearly converted into
sulphate, and the hydrochloric acid formed, together with any other
gases, passes away from the chamber last charged with chloride to the
condensing towers. This part of our Invention can be advantageously
carried into effect in the apparatus described in the Specification of an
Invention, for which we have obtained Letters Patent, bearing. even date
herewith.
Sixth. As an alternative method of rendering the production of
sulphates continuous, we employ a tower or chamber of considerabló
height to contain chloride of sodium of chloride of potassium, and we
pass the current of mixed sulphurous acid gas, air, and water upwards
through the mass. When the lower portion of the chloride is converted
into sulphate, it is withdrawn and fresh chloride added at the top. The
tower or chamber is in height at least three times its diameter or width.
This part of our Invention can only be beneficially employed when the
mass of chloride of sodium or chloride of potassium is packed in the
tower in the manner described under the above third head, and we
only claim the sixth part when the mass of chloride is so packed.
Having now described the nature of our said Invention, and par-
ticularized the same in such manner that others will be enabled to
beneficially carry the several improvements into effect, we claim,-
Under the first head. The employment of mixed sulphurous acid gas,
air, and water vapour, in the proportions mentioned or thereabouts, for
the purposes set forth.
Under the second head. The employment of chloride of sodium and
chloride of potassium, in pieces of the size named or thereabouts for the
purposes set forth.
Under the third head. Placing the pieces of chloride of sodium or
chloride of potassium of smaller size near the sides or inner surfaces
of the chambers, for the purposes set forth.
Under the fourth head. Passing the mixed sulphurous acid gas, air,
and water vapour in succession through the mass of chloride of sodium
or chloride of potassium contained in two or more chambers, for the
purposes set forth.

page_text: Under the fifth head. Rendering the production of sulphate of soda
and sulphate of potassa continuous, by passing the mixed sulphurous
acid gas, air, and water vapour through the mass of chloride of sodium
or chloride of potassium, contained in a series of two or more chambers,
each of which become in their turn the first, intermediate, and last of
the series, substantially as set forth.
Under the sixth head. Rendering the production of sulphate of soda
and sulphate of potassa continuous, by passing the mixed sulphurous
acid gas, air and water vapour through chloride of sodium or chloride of
potassium contained in a high tower or chamber, when the said chlorides
or cither of them are or is packed in the manner described under the
above third head, substantially as set forth.
In witness whereof, I, the said James Hargreaves, have hereunto
set my hand and scal, this Eighteenth day of May, in the year
of our Lord One thousand eight hundred and seventy-one.
In the presence of,
J. T. KING,
Patent Agent,
Liverpool.
JAMES HARGREAVES. (L.S.)