IMPROVEMENTS IN THE MANUFACTURE OF IRON & STEEL AND THE MEANS EMPLOYED THEREFOR
Year: 1878

page_text: LETTERS PATENT to John Hollway, of Jeffrey's Square, in the City of London,
for the Invention of " IMPROVEMENTS IN THE MANUFACTURE OF IRON & STEEL
AND THE MEANS EMPLOYED THEREFOR."
led the 29th April 1879, and dated the 30th October 1878.
PROVISIONAL SPECIFICATION left by the said John Hollway at the Office
of the Commissioners of Patents on the 30th October 1878.
"IMPROVEMENTS
JOHN HOLLWAY, of Jeffrey's Square, in the City of London.
IN THE MANUFACTURE OF IRON & STEEL AND THE MEANS EMPLOYED THEREFOR."
In the first place these improvements are for the production of crude iron with a
consumption of carbon more nearly approaching the theoretical quantity requisite
than is possible in the usual processes. I do this by blowing air through crude
molten iron in the presence of metallic coke or oxide of iron and carbon, and by
the utilization of the heat obtained from the combustion of the carbonic oxide thus
evolved. I add from time to time additional metallic coke or oxide of iron and
carbon, and an thus able to carry on a continuous operation. I employ a vessel
or furnace having tuyeres so arranged that while I am driving air upward through
the molten metal to oxidize the carbon and other metalloids contained therein, I
also drive air downward into the vessel, and thus burn the resulting carbonic oxide.
I utilize the heat from the escaping gases to heat the blasts of air, and I also
regulate the respective quantities which I introduce in order to produce the heat
requisite with the minimum consumption of fuel. The temperature I thus obtain
causes the molten iron rapidly to take up carbon to replace that oxidized, and not
only facilitates the reduction of the oxide of iron, which is in contact with carbon
or with the molten carbide of iron, but also fuses the iron as soon as it is reduced
from the oxide; therefore slag is only a necessity on account of the difficulty in
obtaining oxide of iron without admixture of foreign substances, and as I can
einploy oxide of iron in powder I can first free it as far as possible from impurities,
and when desired make it into metallic coke.

page_text: In the second place these improvements are for the reduction of iron from the
molten-ferriferous-slag-produced-from-pyrites-under my Letters Patent, No. 1131,
dated 21st March 1878.When I desire to produce steel I remove the sulphur
present in the slag by oxidation, either by blast of air or by the addition of oxide
of iron, taking care to keep the mass molten and at a sufficiently high temperature.
I employ a vessel or furnace having a basic or carbonaceous lining, into which I
introduce the molten ferriferous slag after the oxidation of the sulphur, adding
carbonaceous materials, also lime and other bases, and maintaining it fluid by the
combustion of gases above its surface. By these means the slag is kept basic, and
-the-oxide-of-iron-is.decomposed by the reducing substances introduced.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Hollway in the Great Seal Patent Office on the 30th April
1879.
JOHN HOLLWAY, of Jeffrey's Square, in the City of London. "IMPROVEMENTS
IN THE MANUFACTURE OF IRON AND STEEL AND THE MEANS EMPLOYED THEREFOR.",
In the first place these improvements are for the production of crude iron with a
consumption of carbon more nearly approaching the theoretical quantity requisite
than is possible in the usual processes. I do this by blowing air through crude
molten iron in the presence of metallic coke or oxide of iron and carbon, and by
the utilization of the heat obtained from the combustion of the carbonic oxide thus
evolved. I add from time to time additional metallic coke or oxide of iron and
carbon, and am thus able to carry on a continuous operation. I employ in
preference a basic lined vessel or furnace, having tuyeres so arranged that while I
am driving air upward through the molten metal to oxidize the carbon and other
metalloids contained therein I also drive air downward into the vessel, and thus
burn the resulting carbonic oxide. I utilize the heat from the escaping gases to
heat the blasts of air, and I also regulate the respective quantities which I intro-
duce in order to produce the heat requisite with the minimum consumption of fuel.
The temperature I thus obtain causes the molten iron rapidly to take up carbon
to replace that oxidized, and not only facilitates the reduction of the oxide of iron
which is in contact with carbon or with the molten carbide of iron, but also fuses
the iron as soon as it is reduced from the oxide; therefore slag is only a necessity
on account of the difficulty in obtaining oxide of iron without admixture of foreign
substances, and as I can employ oxide of iron in powder I can first free it as far as
possible from impurities, and when desired make it into metallic coke.
The theory of the process is as follows:-
Molten iron, rich in carbon, is run into the vessel, the blast in preference hot having
previously been turned on at both upper and lower tuyeres; iron ore, in preference
in powder, mixed with coke or other fuel, is now charged into the vessel, and
smelting sets in immediately. The ore introduced is thus subjected to a powerful
reducing action by the incandescent carbonic oxide which is burning above the
molten iron at a very elevated temperature. Carbide of iron is formed, which melts,
and continually introduces carbon into the mass of decarburizing iron. The iron
is never decarburized, because of the constant accession of combined carbon, brought
about by the presence of carbon and by the smelting of the crude materials intro-
duced, the silicious and earthy constituents of which form a slag, which accumu
lates at the surface of the molten iron, and from time to time is run off. The gases
which pass off will be mainly carbonic acid and nitrogen, which being at a high
temperature will be utilized to heat the blast. The product will be run out of the
furnace, or poured out at the mouth when occasion requires.
In the second place these improvements are for the reduction of iron from the
molten ferriferous slag produced from pyrites under my Letters Patent, No. 1131,
dated 21st day of March 1878. When I desire to produce steel or iron I remove the
sulphur present in the slag by oxidation, either by a blast of air or by the addition
of oxide of iron, taking care to keep the mass molten and at a sufficiently high
temperature. I employ a vessel or furnace having a basic or carbonaceous lining,
into which I introduce the molten ferriferous slag after the oxidization of the
sulphur, adding carbonaceous materials, either in the gaseous or solid form;
the necessary lime and or other bases, and maintaining it fluid and at a sufficiently
high temperature, either by the combustion of gases above its surface or by intro
ducing carbonic oxide at a sufficiently elevated temperature. By these means the
slag is kept sufficiently basic, and the oxide of iron is decomposed by the reducing
substances introduced.
also

page_text: I therefore claim as new and of my Invention the production of crude iron and
steel in the manner-herein-before-described.
In witness whereof, I, the said John Hollway, have hereunto set my hand
and seal, this Twenty-sixth day of April, in the year of our Lord One
thousand eight hundred and seventy-nine.
Signed & sealed in the
presence of
FRANCIS WILLIAM BARNES,
416, Strand, W.C.,
JOHN LONGMAID,
20, Victoria Grove,
Stoke Newington,
London.
JOHN HOLLWAY.
L.D.)