IMPROVEMENTS IN TREATING IRON ORES AND IN THE FURNACES OR OVENS EMPLOYED FOR SUCH PURPOSE
Year: 1870

page_text: LETTERS PATENT to Alexandre Le Brun-Virloy, of Paris, No. 23,
Boulevard de Strasbourg, Civil Engineer, for the Invention of.
"IMPROVEMENTS IN TREATING IRON ORES AND IN THE FURNACES OR OVENS
EMPLOYED FOR SUCH PURPOSE."
Sealed the 19th July 1870, and dated the 4th February 1870.
PROVISIONAL SPECIFICATION left by the said Alexandre Le Brun-
Virloy at the Office of the Commissioners of Patents, with his
Petition, on the 4th February 1870.
I, ALEXANDRE LE BRUN-VIRLOY, of Paris, No. 23, Boulevard de
Strasbourg, Civil Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN TREATING IRON ORES AND IN THE FURNACES
OR OVENS EMPLOYED FOR SUCH PURPOSE," to be as follows:-
The object of my Invention is a system of furnace so arranged as
to permit the realization for iron ores with the employment of flame
conditions of treatment similar to those produced in blast or high
furnaces. In the upper part of the vertical trough of ordinary blast
furnaces the minerals are first submitted to a sufficient temperature to

page_text: reduce and carburate them, but not high enough to scorify them.
Then by the descent of the charge progressively approaching the tuyeres,
that is to say, the part where the maximum of heat is developed, it
arrives at the temperature of fusion, when it is reduced and carburetted.
This gradual increase of temperature and succession of operations are
indispensable for the success of the treatment in high furnaces where in
solid combustibles placed in contact with the mineral are employed.
It is evident that they are equally indispensible with the employment
of combustible gases and flame. The gas furnace and arrangements
which I proceed to describe produce the same results as the blast
furnace. These furnaces may be either inclined, horizontal, or even
vertical.
The furnace is formed of three parts, 1st, the melting hearth into
which the combustible gases and air that has been previously heated
arrive separately; 2ndly, the melting furnace; and 3rdly, the reducing
and carburetting furnace.
The temperature of the reducing and carburetting furnace ought to be
much less elevated than that of the melting furnace. Therefore, at the end
of the latter and on either side an escape, orifice is made for the flames,
which are led away by two escape, chimneys (chominées d'appel) after
having been utilized either for heating the air and gases, or the pro-
duction of steam, or for other purposes. Only that amount of flame
necessary to maintain the desired temperature is permitted to enter
the reducing furnace. The progress of the furnace is regulated by
dampers which are near the escapements and obturating plates which
more or less. cover the charging orifice at the end of the reducing.
furnace whereby the flames finally escape, after having passed through
the said furnaces.
The iron ores or ferrugineous scorice should before entering the above
<lescribed furnace receive a preparation which consists in reducing them
into very small fragments or even into powder, in mixing them with
the quantity of carbon necessary in order to produce their reduction
and carburation, and with a couvenient quantity of lime or clay, either
to serve as a flux for the gangue (fondant à la gangue) or to closely
unite the different matters, and lastly, in forming them by ordinary :
means into bricks or blocks of any convenient shape. With inclined.
furnaces, the object of which is, to facilitate the progressivo movement
of the ore from the charging orifice to the melting hearth, it is preferred;

page_text: to employ cylindrical blocks, and these may sometimes be made hollow,
which will be found to favour the operation. The furnace is always
kept full of blocks of the ores. In proportion as those nearest to the
fire bridge become melted, the others behind them are pushed forward
and the place of the latter is filled through the charging orifice. Side
openings are arranged in the walls of the furnace at the right and left,
some at the level of the sole plate and others above the blocks of ore
so as to permit of their advance being regulated. These openings when
not required are closed by plugs or shutters of refractory earth or by
other means. The melting ore falls into the melting hearth through
holes made in the fire bridge. The slag passes away through one of the
doors of the melting hearth, and when the latter is full the melted metal
flows through a tap-hole arranged at the bottom.
It is preferred that the carburetting gases should enter the furnaces
through the lower of the two orifices leading into the melting furnace
with a certain pressure in order to avoid the entrance of the air through
the different openings. The air arrives above through the upper of the
orifices, and is directed against the roof of the furnace, the gases
arriving about 4 inches (10 centimetres) below in order that the ores
may be as much as possible in a non-oxydizing medium.
The form, arrangement, and action of the horizontal furnaces are the
same as those of the inclined furnaces. The vertical furnaces differ,
inasmuch that the melting furnace and the reducing and carburetting
furnace, which is always at the back, are the same, and rise vertically
to about 30 inches (80 contimetres) above the fire bridge. At a height
of about 8 feet (2m. 50c.), that is to say, above the vertical lower part
which serves for the melting furnace, are placed two escapements for
the carburetting gases, the same as in the inclined and horizontal
furnaces. The withdrawal by these escapes ought to be sufficiently
active to leave in the upper part of the vertical portion of the furnaco
only the quantity of flame necessary to maintain the temperature for
reduction and carburation. The charging orifice is also stopped by one
or several obturators which permit more or less flame to pass through.
The blocks of ore, which are preferably of a hollow cylindrical form, aro
so charged as to leave between themselves and the walls of the
furnace a sufficient passage for the carburetting gases. These blocks
are preferred to be about 15 inches (10 centimetres) in length and 7
inches (20 centimetres) in diameter, and are arranged horizontally in

page_text: crossed ranks one upon another in the furnace, forming a square column
having much space between its four faces and the circular walls of the
furnace. Side openings and doors are arranged in these walls as in the
inclined and horizontal furnaces in order that the descent of the blocks
may be directed as regularly as possible in proportion as they become
fused.
The reducing and carburetting furnace could be isolated from the
melting furnace, but this would be somewhat to the detriment of
economy.
I can employ all sorts of combustibles and every kind of generator :
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexandre Le Brun-Virloy in the Great Seal
Patent Office on the 1st August 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDRE ]
LE BRUN-VIRLOY, of Paris, No. 23, Boulevard de Strasbourg, Civil
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourth day of February, in the year
of our Lord One thousand eight hundred and seventy, in the thirty- 2
third year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Alexandre Le Brun-Virloy, Her special
licence that I, the said Alexandre Le Brun-Virloy, my executors, admi-
nistrators, and assigns, or such others as I, the said Alexandre Le Brun-
Virloy, my executors, administrators, and assigns, should at any time 2
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 “Ix-
PROVEMENTS IN TREATING IRON ORES AND IN THE FURNACES OR OVENS EMPLOYED
FOR SUCH PURPOSE," upon the condition (amongst others) that I, the
said Alexandre Le Brun-Virloy, 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 3

page_text: 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 Alexandre Le Brun-Virloy, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement thereof, reference being had
to tho accompanying Drawings, and to- the letters and figures marked
thereon, that is to say
17
.
The object of my Invention is a system of furnace so arranged as to
permit the realization for iron ores with the employment, of flame; of
conditions of treatment similar to those produced, in blast or high.
furnaces. In the upper part of, the vertical trough of ordinary blast,
furnaces the minerals are first submitted to a sufficient temperature to.
reduce and carburate them, but not high enough to scorify them. Then,
by: the descent of the charge progressively approaching the tuyeres, that
is to say, the part where the maximum of heat is developed,. it arrives at
the temperature of fusion when it is. reduced and carburetted., This
gradual increase of temperature and succession of operations are indis-
pensable for the success of the treatment in high furnaces wherein solid
combustibles placed in contact with the mineral are employed. It is.
evident that they are equally indispensable with the employment of
combustible gases and flame. The gas furnaces. and arrangements.
which I proceed to describe produce the same results as the blast
furnace. These furnaces may be either inclined, horizontal, or even
vertical.
.
i
I will first take an inclined furnace by way of example, which will be
seen on reference to Figures 1 and 2 of the accompanying Drawings..
The furnace is formed of three parts; first; the melting heartli 'A' into
which the combustible gases and air that has been previously heated
arrive separately; second, the melting furnace B; and, thirdly, the
reducing and carburetting furnace C.
The temperature of the reducing and carburetting furnace ought to
be much less elevated than that of the melting furnace. Therefore at.
the end of the latter and on either side an escape orifice a, a¹, is made.
for the flames which are led away by two escape chimneys K, (cheminées.
d'appel) after having been utilized either-for-heating-the-air-and-gases,-

page_text: or for the production of steam or for other purposes. Only that amount
of flame necessary to maintain the desired temperature is permitted to
enter the reducing furnace. The progress of the furnace is regulated
by dampers b, b', which are near the escapements and obturating plates
d, d², d², which more or less cover the charging orifice D at the end of
the reducing furnace, whereby the flames finally escape after having
passed through the said furnace.
The iron ores or ferruginous scoric should before entering the above-
described furnace receive a preparation which consists in reducing them
into very small fragments, or even into powder, in mixing them with the
quantity of carbon necessary in order to produce their reduction and
carburation, and with a convenient quantity of lime or clay, cither to
serve as a flux for the gangue (fondant à la gangue) or to closely unite
the different matters, and lastly in forming them by ordinary means
into bricks or blocks of any convenient shape. With inclined furnaces:
such as that shown at Figure 1, the object of which is to facilitate the
progressive movement of the ore from the charging orifice D to tho
melting hearth A, it is preferred to employ cylindrical blocks J, and
these may sometimes be made hollow as shown in the Drawings, which
will be found to favor the operation. The progress of the operation
will be immediately understood by reference to Figures 1 and 2. The
furnace is always kept full of blocks of the ores. In proportion as those
nearest to the fire bridge E become melted the others behind them are
pushed forward, and the place of the latter is filled through the charging
orifice. Side openings L are arranged in the walls of the furnace at
the right and left, some at the level of the sole plate, and others above
the blocks of ore so as to permit of their advance being regulated.
These openings when not required are closed by plugs or shutters of
refractory carth or by other means. The melting ore falls into tho
melting hearth A through holes made in the fire bridge E. The slag:
passes away through one of the doors G of the melting hearth, and
when the latter is full tho melted metal flows through a tap-hole F
arranged at the bottom.
It is preferred that the carburetting gases should enter the furnaces
through the lower II of the two orifices leading into the melting furnace
with a certain pressure in order to avoid the entrance of the air through
the different openings. The air arrives above through the upper one I
of the orifices, and is directed against the roof of the furnaces, the gases

page_text: arriving about 4 inches (10 centimetres) below, in order that the ores.
may be as much as possible in a non-oxidizing medium.
The form, arrangement, and action of the horizontal furnaces aro
the same as those of the inclined furnaces. The vertical furnaces,
one of which is represented in three views in Figures 3, 4, and 5,
differ inasmuch as that the melting furnace B and the reducing
and carburetting furnace O which is always at the back are of
similar section so as practically to be the same and riso vertically to
about 30 inches (80 centimetres) above the fire bridge at a height of
about 8 feet (2m. 50c.), that is to say, above the vertical lower part
which serves for the melting furnace are placed two escapements a, a',
for the carburetting gases, the same as in the inclined and horizontal
furnaces. The withdrawal by these escapes ought to be sufficiently
active to leave in the upper part of the vertical portion of the furnace
only the quantity of flame necessary to maintain the temperature for
reduction and carburation. The charging orifice D is also stopped by
one or several obturators & which permit more or less flame to pass
through. The blocks of ore J, which are preferably of a hollow
cylindrical form, as seen in Figure 3, are so charged as to leave between
themselves and the walls of the furnace a sufficient passage for the
carburetting gases. These blocks are preferred to be about 15 inches
(40 centimetres) in length and 7 inches (20 centimetres) in diameter,
and are arranged horizontally in crossed ranks one upon another in the
furnace, forming a squaro column leaving plenty of space between its
four faces and the circular walls of the furnace. Side openings and doors
are arranged in these walls as in the inclined and horizontal furnaces in
order that the descent of the blocks may be directed as regularly as
possible in proportion as they becomo fused.
The reducing and carburetting furnace could be isolated from tho
melting furnace, but this would be somewhat to the detriment of
economy.
I can employ all sorts of combustibles and every kind of generator
for the production of the combustible gases.
And having now described the nature of my said Invention, and in
what manner the same is to be performed, I declare that I claim,—
Firstly. Treating iron ores substantially as above described and illus.
trated in the accompanying Drawings.

page_text: And, secondly. The construction and arrangements of furnaces sub-
stantially as above described and shewn in the accompanying Drawings,
whereby conditions similar to those of blast furnaces are produced for
the treatment of iron ores.
In witness whereof, I, the said Alexandre Lo Brun-Virloy, have 5
hereunto set my hand and seal, this Twelfth day of July, in the
year of our Lord One thousand eight hundred and seventy.
.Witness,
C. LAFOND,
Civil Engineer,
A. LE BRUN VIRLOY. (L.S.)
23, Boulevart de Strasbourg,
Paris.