IMPROVED MEANS OF OBTAINING SALTS OF AMMONIA FROM COMBUSTIBLE GASES
Year: 1883

page_text: LETTERS PATENT to John Addie of Glasgow in the County of Lanark,
Ironmaster for an Invention of "IMPROVED MEANS OF OBTAINING SALTS OF
AMMONIA FROM COMBUSTIBLE GASES" partly his own invention and partly a
communication to him from James Addio presently residing at Bilbao in the
Kingdom of Spain
PROVISIONAL SPECIFICATION left by the said John Addie at the Office
of the Commissioners of Patents on the 30th June 1883.
"IMPROVED
MEANS OF OBTAINING SALTS OF AMMONIA FROM COMBUSTIBLE GASES;" partly my
own Invention and partly a communication to me from James Addie presently
residing at Bilbao, in the Kingdom of Spain;
JOHN ADDIE, of Glasgow, in the County of Lanark, Ironmaster,
This Invention is a development of the means or process of recovering ammonia
from furnace gases described in the Specification of Letters Patent N° 4758 Dated
6th October 1882.
According to the present Invention the ammonia which is contained in
combustible gases, such as the gases obtained from blast furnaces, coking ovens, and
gas producers is directly converted and recovered as sulphato of ammonia by a
continuous process consisting of the following stages, vis: (1) The combustible
gases are charged or intermixed with sulphurous acid gas in sufficient quantity to
combine with and fix the ammonia contained in them. (2) The gases are submitted
to the action of a scrubber or to equivalent action to dissolve the sulphite formed,
and (3) The solution of sulphite of ammonia is oxidised by forcing or injecting air
thereinto.
The first two stages of the process may be carried out in the manner and by
means of apparatus such as is described in the Specification above referred to, as
adapted for the production of sulphite of ammonia from furnace gases, and tho
completing stage of oxidising the solution of sulphite to convert it into sulphate of
ammonia inny be effected by means of apparatus of the kind employed for aerating
or oxidising other liquid solutions, such apparatus being devised to agitate or

page_text: atomise the liquid while bringing air into intimate admixture with it. Hydrated
oxide of manganese or similar carrying agents may be added to the solution to
facilitate the oxidation of the sulphite.
To prevent the formation of hyposulphite of ammonia in the first part of the
process, the stream of sulphurous acid gas is passed through a water trap or
similar device to eliminate uncombined sulphur, before being mixed with the
combustible gases.
According to a modification of the process referred to, whereby sulphite of
ammonia is the product directly obtained, the sulphurous acid gas, which is
employed to combine with and fix the ammonia in the combustible gases, is
generated by adding sulphur or sulphurous shale or other substances containing
sulphur to the coal or carbonaceous matter in the gas producer or similar apparatus
from which the combustible gases are obtained; and the sulphite formed by the
union of the ammonia in the gases, with the sulphurous acid gas thus generated
is recovered in solution by passing the gases through a scrubber in which water is
caused to circulate.
According to a further modification of the Invention, the ammonia contained in
combustible gases is directly recovered as sulphite by passing the gases (without
admixture with sulphurous acid gas) through a scrubber or similar apparatus
within which is circulated a solution of sulphurous acid.
The sulphite obtained by either of the variations of the process last described
may be directly converted into sulphate by oxidation or it may be otherwise
utilised.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Addie in the Great Seal Patent Office on the 29th December
1883.
"
JOHN ADDIE, of Glasgow, in the County of Lanark, Iron Master IMPROVED
MEANS OF OBTAINING SALTS OF AMMONIA FROM COMBUSTIBLE GASES;" partly my
own Invention and partly a communication to me from James Addie presently
residing at Bilbao in the Kingdom of Spain.
This Invention is a development of the means or process of recovering ammonia
from furnace gases described in the Specification of Letters Patent N° 4758, Datod
6th October, 1882.
According to the present Invention the ammonia which is contained in
combustible gases, such as the gases obtained from blast furnaces, coking ovens, and
gas producers is directly converted and recovered as sulphate of ammonia by a
continuous process consisting of the following stages, vist (1) The combustible gases
are charged or intermixed with sulphurous acid gas in sufficient quantity to
combine with and fix the ammonia contained in them. (2) The gases are
submitted to the action of a scrubber or to equivalent action to dissolve the
sulpbite formed; and (3) The solution of sulphite of ammonia is oxidised by forcing
or injecting air thereinto.
The first two stages of the process may be carried out in the manner and by
means of apparatus such as is described in the specification abovo referred to, as
adapted for the production of sulphite of ammonia from furnace gases; and the
completing stage of oxidising the solution of sulphite to convert it into sulphate
of ammonia may be effected by means of apparatus of the kind employed for
aerating or oxidising other liquid solutions, such apparatus being devised to agitate
or atomise the liquid while bringing air into intimate admixture with it. Hydrated
oxide of manganese or similar carrying agents may be added to the solution to
facilitate the oxidation of the sulphite.
To prevent the formation of hyposulphite of ammonia in the first part of the
process the stream of sulphurous acid gas is passed through a water trap or
sulphur burner or similar device to eliminate uncombined sulphur before being
mixed with the combustible gases.
According to a modification of the process referred to, whereby sulphito of
ammonia is the product directly obtained, the sulphurous acid gas which is
employed to combine with and fix the ammonia in the combustiblo gases is
generated by adding sulphur or sulphurous shale or other substances containing
sulphur to the coal or carbonaceous matter in the gas producer or similar
apparatus from which the combustible gases are obtained; and the sulphite formed
by the union of the ammonia in the gases with the sulphurous acid gas thus
generated is recovered in solution by passing the gases through a scrubber in
which water is caused to circulato.
The sulphite obtained by this process may be directly converted into sulphate
by oxidation, or it may be otherwise utilised.
Having thus particularly described the said Invention, and the manner in which
the same is to be performed, I declare that what I claim is ;-
First. The herein described process of obtaining sulphate of ammonia from
combustible gases, which consists in mixing sulphurous acid with such gases, to fix
the ammonia contained therein, then condensing or dissolving in water the sulphite
of aminonia thus formed, and finally oxidising the solution by forcing or injecting
air thereinto, all substantially as herein set forth.

page_text: Second. The herein described process of obtaining salts of ammonia from
combustible gases, which consists in mixing sulphur or sulphur compounds with
the fuel in the gas generators, to fix the ammonia formed therein, and then
subjecting the gases to the action of scrubbers or to equivalent action for the
purpose of dissolving or condensing and recovering from the gases the sulphite or
other salts of ammonia they contain, substantially as herein set forth.
In Witness Whereof, I the said John Addie, have hereunto set my hand and
seal this Twenty sixth day of December, in the year of our Lord one thousand
eight hundred and eighty threc.
Witness
WALLACE FAIRWEATHER C.E.
Fel. Inst. Patent Agents
96 Buchanan Street
Glasgow,
JOHN ADDIE (L.S.)