Year: 1886

page_text: Date of Application, 19th May, 1886
Complete Left, 21st Feb., 1887.
Complete Accepted, 22nd Mar., 1887.
[Communicated from abroad by LA SOCIÉTÉ ANONYME DES PRODUITS CHIMIQUES
DE ST. DENIS, of 52, Rue Taitbout, Paris, France, represented by ACHILLE
SÉNEZE, administrateur Délégué.]
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of this Invention to be as follows:-
This Invention has for its object the reduction and fusion of the ashes of pyrites
and other pulverulent iron ores, after having eliminated any objectionable elements
they may contain, without mixing them with other ores and by treating them
separately in their pulverulent form.
The Invention consists essentially in effecting a thorough preliminary purification
of the ore, and then intimately mixing it in a finely divided condition with coal, and
operating the reduction and fusion in a single apparatus without any admixture of
other ores. If it is desired to obtain a finished product of superior quality in a single
operation, it is absolutely indispensable that the sulphur should be first entirely
eliminated. Although, in effecting the reduction of an intimate mixture of ashes of
pyrites and coal, sulphide of carbon is formed at the reducing temperature and a
portion of the sulphur is thus eliminated, but when the roasting has been imperfect
and the proportion of sulphur left is consequently considerable i.e. from one to two
per cent., this elimination is insufficient and it is necessary to effect a preliminary
purification by a rapid roasting at a high temperature so directed as to ensure the
elimination of the whole of the sulphur. In effecting a complete roasting, it is also
easy to extract the copper from the pyrites containing that metal and which are also
employed in the manufacture of sulphuric acid without having recourse to the process
of chloridizing thus, the sulphur, having more affinity for the copper than the iron,
retains the former in the state of sulphide but if the roasting is carried sufficiently far
to drive off the whole of the sulphur the copper will then be in the state of oxide. By

page_text: substituting for the chloridizing process, sulphatation by means of dilute sulphuric
acid oxides of iron may be obtained from cupreous pyrites, from which both the
sulphur and the copper have been eliminated.
According to this Invention, the reduction is effected by intimately mixing the ore
with the pulverized coal or by a current of reducing gases by causing this mixture to
gradually traverse a regenerative steel furnace until it falls in the state of iron dust.
From the foregoing it will be seen that it is unnecessary to mix the ore with the
reducing agent at the commencement of the operation, and that a single operation
suffices to eliminate the whole of the sulphur as well as to effect the reduction and
melting of the purified ore in such manner that the charge of pulverulent ore is
delivered in the form of steel without undergoing any manipulation or cooling. The
complete desulphurization and reduction of the ore may be effected by various
mechanical means, and the apparatus, hereinafter described with reference to the
accompanying drawings, which is given merely by way of example, is based on the
principle of continuous mechanical agitation with a circulation of the matters in
the reverse direction to that of the gases.
Figure 1, is a vertical section, and figure 2 a horizontal section of the furnace.
The furnace is of the vertical kind with any suitable number of superposed hearths B
upon each of which works a cast or wrought iron rake keyed on a vertical shaft C
through which water is made to circulate, the water being introduced through the
box D at bottom and passing out through the box E at top. The matters to be
treated fed by the hopper F, pass down the inclined shoot G on to the first hearth B
and thence downwards from one to another of the several hearths through the series
of apertures H which are inclined so as to conduct the matters as near the centre as
possible. From the bottom hearth the reduced matters pass down into a melting
furnace I (represented on a larger scale in figures 3 and 4). Doors J are provided
on a level with each hearth to afford access thereto for repairs etc., these doors being
luted during the operation, and openings K K similarly luted are made in the outer
walls to facilitate the clearing of the communicating passages in the event of any
obstruction. It will be observed that the discharge apertures are placed alternately
at diametrically opposite points so that the matters are caused to circulate in a zig-zag
direction through the furnace while being at same time stirred and projected from the
centre towards the circumference. The gases are caused to circulate in the reverse
direction, whether for reducing or desulphurizing, in the following manner; The
reducing gases from the generator are introduced at L. and, after having traversed
from end to end of the hearth, pass upwards through flues formed in the walls (see
figure 2) to the hearth next above, and after having traversed the same pass through
flues at the opposite end to the next hearth, and so on in succession until they reach
the desulphurizing zone, at which point hot-air from the regenerator is introduced
at N whereby the reducing gases are burnt and the mixture, having become oxidizing,
traversing the upper hearths in succession as before, and escapes at N' into a chamber
in which the dust is deposited. The powdered coal is introduced at S in regulated
quantities in order to effect the desired degree of carburization. The construction of
the rakes is shown on a larger scale in figures 5. 6. and 7. They are composed of iron
bars provided with teeth R. and passing through guides O in the hollow shaft C of
such form as to allow of their ready insertion and fixing. The melting furnace is
shown in figures 3 and 4 and presents some novel features. The communication
between it and furnace A is so arranged as to enable it to be readily replaced. The
reduced iron falls through the two throats N N of refractory material which can be
easily replaced in case of repairs being needed. Moreover, as it is essential to protect
the pyrophoric iron from the action of air and from the draught, the reduced iron is
made to fall into a space enclosed by graphite, magnesia, or other composition capable
of withstanding the high temperature and of not being acted on by the silicon and
iron, said space being in communication with the metallic bath by means of
orifices 0 and a vertical slit P. Further, with a view to obtain a reducing or
neutral flame, the flame on penetrating into the furnace meets a diaphragin Q formed
of refractory material with a number of perforations upon which rests a screen of wood

page_text: charcoal supplied by the hopper R. The furnace is heated in the following manner;
the combustible gases are supplied by the gas-producer S and introduced at pipe T
while the hot-air from the regenerator U passes through flue V into chamber X
mixing with the combustible gases at the orifices YY which thus form a sort of
blow-pipe, the gases after passing through the furnace being returned to the regenerator
by the Blue Z.
When the ore is cupreous, and requires to be purified before conversion into metal
the desulphurization should be effected in a separate apparatus, such as represented in
figure 8 which being a simplified arrangement of the preceding apparatus needs but a
short description. The furnace A is divided into three or more compartments and is
supported upon columns. The matters to be treated are supplied to the upper
compartment by a hopper D and pass from thence downwards into the second and
third compartments. The matters are kept constantly stirred by a series of spiral
arms which conduct the matters gradually along the hearth and supply them to the
hearth next below while air is caused to circulate in the reverse direction. These
arms are keyed on hollow shafts through which water is made to circulate. The
matters are discharged from the lowest compartment completely desulphurized and
the copper is then extracted by means of sulphuric acid as before mentioned, after
which the reduction is effected either in a similar furnace or in the vertical furnace
before described:
In order to obtain ashes of pyrites entirely free from sulphur and copper it is
necessary that they should be reduced to impalpable powder. After completely
roasting the copper will be in the form of oxide and can be readily separated by
washing with acidulated water, and afterwards with pure water, to remove all trace of
acid or of soluble salts. It has been found that in this condition the oxide of iron has
a marked tendency to adhere together and agglomerate, and that by the addition of a
very small quantity of some material capable of cementing the particles an artificial
ore is obtainable which, after moulding, drying, and baking, like ordinary bricks,
becomes hard and resistant. The agglutinative material may eitherbe an alkaline
earth in suspension, certain clays, and alkaline silicates. The operation is very simple,
it being only essential that the materials should be intimately mixed together. The
bricks thus obtained containing neither sulphur nor copper, it is only necessary to
regulate the quantity of carbon and obtain a very high temperature in order to
produce cast steel.
Instead of charging the matters in layers alternately with the fuel, the furnace is
heated by a double blowing apparatus, one supplying hot air and the other gas from
the producer which is introduced at the same pressure as the hot air. The air furnace
thus constitutes a regenerative gas furnace. It differs in form from that of an ordinary
blast-furnace in that the proportion of gangue being but very small, the reduction is
very easily effected, the charges pass very quickly through the furnace, and the gases
pass off at a high temperature.
A. M. CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane, London,
Patent Agents.

page_text: Process and Apparatus for the Treatment of Iron Ores for the
Manufacture of Steel.
1, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of this Invention (a communication to me from
abroad by La Société Anonyme des Produits Chimiques de St. Denis of 52 Rue Taitbout,
Paris, France, represented by Achille Senèze, Administrateur Delégué), and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement:-
This Invention has for its object the reduction and fusion of the ashes of pyrites and
other pulverulent iron ores, after having eliminated any objectionable elements they
may contain, without mixing them with other ores, and by treating them separately
in their pulverulent form.
The Invention consists essentially in effecting a thorough preliminary purification
of the ore, and then intimately mixing it in a finely divided condition with wood
charcoal and operating the reduction and fusion in a single apparatus without any
admixture of other ores. If it is desired to obtain a finished product of superior
quality in a single operation, it is absolutely indispensable that the sulphur should be
first entirely eliminated. Although, in effecting the reduction of an intimate mixture
of ashes of pyrites and charcoal sulphide of carbon is formed at the reducing
temperature and a portion of the sulphur is thus eliminated, yet, when the roasting
has been imperfect and the proportion of sulphur left is consequently considerable,
i.e. from one to two per cent., this elimination is insufficient and it is necessary to
effect a preliminary purification by a rapid roasting at a high temperature so directed
as to ensure the elimination of the whole of the sulphur.
In effecting a complete roasting, it is also easy to extract the copper from the
pyrites containing that metal and which are also employed in the manufacture of
sulphuric acid without having recourse to the process of chloridizing, thus, the sulphur,
having more affinity for the copper than the iron, retains the former in the state of
sulphide, but if the roasting is carried sufficiently far to drive off the whole of the
sulphur, the copper will then be in the state of oxide. By substituting, for the
chloridizing process, sulphatation by means of dilute sulphuric acid, oxides of iron
may be obtained from cupreous pyrites from which both the sulphur and the copper
have been eliminated.
According to this Invention, the reduction is effected by intimately mixing the ore
with the pulverized charcoal or by a current of reducing gases by causing this mixture
to gradually traverse a regenerative steel furnace until it falls in the state of iron dust.
From the foregoing it will be seen that it is unnecessary to mix the ore with the
reducing agent at the commencement of the operation and that a single operation
suffices to eliminate the whole of the sulphur as well as to effect the reduction and
melting of the purified ore in such a manner that the charge of pulverulent ore is
delivered in the form of steel without undergoing any manipulation or cooling.
This complete desulphurization and reduction of the ore may be effected by various
mechanical means, and the apparatus, hereinafter described with reference to the

page_text: accompanying drawings, which is given merely by way of example, is based on the
principle of continuous mechanical agitation with a circulation of the matters in
the reverse direction to that of the gases.
Figure 1 is a vertical section, and figure 2 a horizontal section of the furnace. The
furnace A is of the vertical kind with any suitable number of superposed hearths B
upon each of which works a cast or wrought iron rake keyed on a vertical shaft C
through which water is made to circulate, the water being introduced through the
box D at bottom and passing out through the box E at top. The matters to be
treated, fed by the hopper F, pass down the inclined shoot G on to the first hearth B
and thence downwards from one to another of the several hearths through the series of
apertures H which are inclined so as to conduct the matters as near the centre as
possible. From the bottom hearth the reduced matters pass down into a melting
furnace I (represented on a larger scale in figures 3 and 4). Doors J are provided
on a level with each hearth, to afford access thereto for repairs, etc., these doors being
luted during the operation, and openings K. K similarly futed are made in the outer
walls to facilitate the clearing of the communicating passages in the event of any
obstruction. It will be observed that the discharge apertures are placed alternately
at diametrically opposite points, so that the matters are caused to circulate in a zig-zag
direction through the furnace while being at same time stirred and projected from the
centre towards the circumference.
The gases are caused to circulate in the reverse direction, whether for reducing or
desulphurizing in the following manner-The reducing gases from the generator are
introduced at L and, after having traversed from end to end of the hearth, pass
upwards through flues formed in the walls (see figure 2) to the hearth next above
and, after having traversed the same pass through flues at the opposite end to the next
hearth and so on in succession, until they reach the desulphurizing zone at which point
hot-air from the regenerator is introduced at N whereby the reducing gases are burnt,
and the mixture, having become oxidizing, traverses the upper hearths in succession as
before, and escapes at N into a chamber in which the dust is deposited. The powdered
charcoal is introduced at S, in regulated quantities in order to effect the desired degree
of carburization. The construction of the rakes is shewn, on a larger scale, in
figures 5, 6, and 7. They are composed of iron bars P provided with teeth R, and
passing through guides O in the hollow shaft C, of such form as to allow of their ready
insertion and fixing. The melting furnace is shewn in Figures 3 and 4 and presents
some novel features. The communication between it and furnace A is so arranged as
to enable it to be readily replaced. The reduced iron falls through the two
throats N, N, of refractory material which can be easily replaced in case of repairs
being needed. Moreover, as it is essential to protect the pyrophoric iron from the
action of air and from the draught, the reduced iron is made to fall into a space
enclosed by graphite, magnesia, or other composition capable of withstanding the high
temperature and of not being acted on by the silicon and iron, said space being in
communication with the metallic bath by means of orifices 00 and a vertical slit P.
Further, with a view to obtain a reducing or neutral flame, the flame, on penetrating
into the furnace meets a diaphragm Q formed of refractory material with a number of
perforations upon which rests a screen of wood-charcoal, supplied by the hopper R.
The furnace is heated in the following manner;-The combustible gases are
supplied by the gas-producer S and introduced at pipe T, while the hot air from the.
regenerator U passes through flue V into chamber X mixing with the combustible
gases at the orifices Y Y which thus form a sort of blow-pipe, the gases, after passing
through the furnace, being returned to the regenerator by the flue Z.
When the ore is cupreous and requires to be purified before conversion into metal,
the desulphurization should be effected in a separate apparatus, such as represented
in figure 8, which, being a simplified arrangement of the preceding apparatus, needs
but a short description. The furnace A is divided into three or more compartments
and is supported upon columns. The matters to be treated are supplied to the upper
compartment by a hopper D and pass from thence downwards into the second and
third compartments. The matters are kept constantly stirred by a series of spiral

page_text: arms which conduct the matters gradually along the hearth and supply them to the
hearth next below while air is caused to circulate in the reverse direction. These arms
are keyed on hollow shafts through which water is made to circulate. The matters
are discharged from the lowest compartment completely desulphurized and the copper
is then extracted by means of sulphuric acid, as before mentioned, after which the
reduction is effected either in a similar furnace, or in the vertical furnace before
described.
In order to obtain ashes of pyrites entirely free from sulphur, and copper, it is
necessary that they should be reduced to impalpable powder. After completely
roasting, the copper will be in the form of oxide, and can be readily separated by
washing with acidulated water, and afterwards with pure water, to remove all trace of
acid, or of soluble salts. It has been found that, in this condition, the oxide of iron
has a marked tendency to adhere together and agglomerate, and that, by the addition
of a very small quantity of some material capable of cementing the particles, an
artificial ore is obtainable which, after moulding, drying, and baking, like ordinary
bricks, becomes hard and resistant. The agglutinative material may either be an
alkaline carth in suspension, certain clays, and alkaline silicates. The operation is
very simple, it being only essential that the materials should be intimately mixed
together. The bricks thus obtained, containing neither sulphur nor copper, it is only
necessary to regulate the quantity of carbon and obtain a very high temperature in
order to produce cast steel.
Instead of charging the matters in layers alternately with the fuel, the furnace is
heated by a double blowing apparatus, one supplying hot air, and the other gas from
the producer, which is introduced at the same pressure as the hot air. The air furnace
thus constitutes a regenerative gas furnace. It differs in form from that of an ordinary
blast furnace, in that, the proportion of gangue being but very small, the reduction is
very easily effected, the charges pass very quickly through the furnace, and the gases
pass off at a high temperature.
Having now particularly described and ascertained the nature of the said Invention,
and in what manner the same is to be performed, I declare that what I claim is
:-
1st. The herein described process for the direct extraction of steel from ashes of
iron pyrites, which consists in reducing the pulverized ore, either by means of
charcoal in admixture therewith, or by means of reducing gases from a generator,
and fusing the reduced metal in a regenerative steel furnace, the whole of the sulphur,
copper, and other impurities being eliminated, as specified.
2nd. The apparatus for effecting the complete desulphurization and reduction of
non cupreous ore by means of charcoal or reducing gases, and the fusion of the metal
in one continuous operation as herein before described and illustrated in the drawings.
3rd. The apparatus for effecting the preliminary desulphurization of cupreous iron
pyrites by oxidizing the copper, and afterwards extracting it by means of sulphuric
acid, as hereinbefore described and illustrated in the drawings.
4th. The employment, in said apparatus, of hollow shafts in which water is caused
to circulate for the purpose of preventing their destruction by the high temperature,
as described.
A. MELVILLE CLARK.
By A. M. & Wm. Clark,.
53, Chancery Lane, London
Patent Agents.