Iron for the Manufacture of Iron and Steel.
Year: 1885

page_text: Iron for the Manufacture of Iron and Steel.
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 a communication to me
from abroad by Charles Cholat (Metallurgist) of 6 Place de l'Hôtel de Ville, Saint
Etienne, and François Mercier (Metallurgist) of the Hauts Fourneaux de Châsse, of
Châsse (Isère) both in France to be as follows:-
This invention relates to processes and apparatus for refining crude cast iron as
it comes from the blast furnace, the hot blast of which is utilised, for dephosphorizing
and desulphurizing the cast iron and converting it into iron or steel.
The cast iron is run from the blast furnace into an oscillating or fixed apparatus
lined with ore or other basic material, and provided at one side with tuyeres so
placed as to give the blast an upwardly inclined direction. The quantity of cast
iron introduced into the apparatus depends on the available pressure and amount
of the blast. The apparatus having been previously heated, a mixture of rich
hammer scale lime, calcareous ore and fluor spar in the proportion of about 5 per
cent of the weight of cast iron, is introduced therein, in a pulverized condition.
Any other mixture of pulverized or fluid oxidizing and basic materials may how-
ever be substituted. On the cast iron being run in, it is raised by the action of
the blast to one side into a highly oxidizing atmosphere and falls again onto the
basic material; under the action of hot air in presence of the bases, the silicon,
sulphur and phosphorus are converted into silicates, sulphates and phosphates,
while the manganese and carbon also dissappear.
The combustion of the carbon produces but little carbonic oxide which in any case
does not act as a reducing agent upon the phosphates and sulphates formed; as being
formed above the slag it does not pass through it. The slag becomes rapidly
liquified and very fluid. It has been found by experiment that in about 7 or
8 minutes, the silicon and manganese entirely disappear and the phosphorus and
sulphur are reduced by three fourths and the carbon by one half. A refined iron
CD 071

page_text: is thus obtained which is still sufficiently fluid to be cast for use without further
treatment.
If it is desired to obtain steel, the iron is run onto a basic hearth and the Martin
process rapidly completes the purification. The absence of silicon tends greatly in
this case to preserve the basic lining.
To produce malleable iron, the blowing operation is continued for twelve or
thirteen minutes when iron, which forms into pasty lumps, and is of absolute
purity, is obtained. By moderating the blast and imparting an oscillatory motion
to the apparatus, the iron may be obtained in the form of a ball or several balls if
the sole be divided into compartments by low division walls of basic bricks. After
the liquid slag has been tapped off the balls are removed, shingled and if necessary
rolled. In carrying out the invention in practice, it is preferred to employ the
apparatus represented in the accompanying drawing. This apparatus is mounted
on trunnions M and provided with a tuyere box N to which the blast is conveyed
through the trunnions M as in the Bessemer converter. A second set of tuyeres
may be placed at the same or a different side to the first but at a higher level, for
the purpose of increasing the oxidizing power of the atmosphere into which the cast
iron is projected. O is the tapping hole and PQ a removable cover which can
either be lifted off or rocked on point P.
L is the chimney shaft and T the tuyeres. When the operation is terminated
and after balling, the cover P Q is removed, the slag which is still liquid is run off
and the apparatus turned in the direction of the arrow until the balls drop into a
carriage placed in a trench beneath the apparatus for the purpose of being con-
veyed to the hammer or the press. The blooms produced may be rolled with or
without being reheated or treated in the Martin furnace.
With the apparatus above described the cold blast may also be used and cast
iron which has been remelted in the cupola may be treated, the operation being
performed in the same way and the reactions being similar.
All the above described operations may be performed in the Bessemer converter
provided the position of the tuyeres be altered.

page_text: Iron for the Manufacture of Iron and Steel.
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 (a communication to me
from abroad by Charles Cholat (Metallurgist) of 6 Place de l'Hotel de Ville, Saint
Etienne, and François Mercier (Metallurgist) of the Hauts Fourneaux de Châsse,
of Chasse (Isère) both in France, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement :-
This Invention relates to processes and apparatus for refining crude cast
iron as it comes from the blast furnace, the hot blast of which is utilized, and
for dephosphorizing and desulphurizing the cast iron and converting it into iron
or steel.
The cast iron is run from the blast furnace into an oscillating or fixed apparatus
lined with ore or other basic material, and provided at one side with tuyeres so
placed as to give the blast an upwardly inclined direction. The depth of the iron
above the tuyeres depends on the available pressure and amount of the blast. The
apparatus having been previously heated, a mixture of rich hammer scale, lime,
calcareous ore and fluor spar in the proportion of about 5 per cent of the weight of
cast iron, is introduced therein, in a pulverized condition. Any other mixture of
pulverized or fluid oxidizing and basic materials may however be substituted. On
the cast iron being run in, it is raised by the action of the blast to one side into a
highly oxidizing atmosphere and falls again onto the basic materials, under the
action of hot air; in presence of the bases, the silicon, sulphur and phosphorus are
converted into silicates, sulphates and phosphates, while the manganese, and carbon
also disappear.
The combustion of the carbon produces but little carbonic oxide which in any
case does not act as a reducing agent upon the phosphates and sulphates formed;
as being formed above the slag, it does not pass through it. The slag becomes
rapidly liquified and very fluid. It has been found by experiment that in about
7 or 8 minutes, the silicon and manganese entirely disappear and the phosphorus
and sulphur are reduced by three fourths and the carbon by one half A refined
iron is thus obtained which is still sufficiently fluid to be cast for use without
further treatment.
If it is desired to obtain steel, the iron is run onto a basic hearth and the Martin
process rapidly completes the purification. The absence of silicon tends greatly in
this case to preserve the basic lining.
To produce malleable iron, the blowing operation is continued for twelve or
thirteen minutes when iron, which forms into pasty lumps and is of absolute
purity, is obtained. By moderating the blast and imparting an oscillatory motion
to the apparatus, the iron may be obtained in the form of a ball or several balls if
the sole be divided into compartments by low division walls of basic bricks.
After the liquid slag has been tapped off, the balls are removed, shingled and if
necessary rolled.

page_text: By prolonging the blowing operation, instead of obtaining iron in lumps, fluid
steel may be produced in which case cast iron would be employed, containing a
certain proportion of silicon and phosphorus, that is to say, combustible matters
capable of devoloping sufficient heat to maintain the bath in a fluid condition.
In carrying out the Invention in practice it is preferred to employ the apparatus
represented in the accompanying drawing in which Figure 1 represents an elevation
and Figure 2 a horizontal section of the apparatus taken on line 1—2.
Figure 3 is a part section of the apparatus taken on line 3, 4.
Figure 4 is a vertical section taken on line 5. 6 of Figure 5, which is a half plan
of the apparatus.
Figure 6 is a top view of the tuyere box.
The same letters of reference, indicate the same parts in all the figures.
The apparatus is mounted on trunnions M and provided with tuyere box N to
which the blast is conveyed through the trunnion M as in the Bessemer converter.
A second set of tuyeres may be placed at the same or a different side to the first,
but at a higher level and above the bath, for the purpose of increasing the
oxidizing power of the atmosphere into which the cast iron is projected.
I am aware that several rows of tuyeres have before been employed but these
always directed the blast into the midst of the bath.
The blast from tuyeres S is introduced by pipes U branched upon the trunnion M.
O is the mouth of converter and P, a removable cover which can be quickly lifted
off by means of the handles Q, R opening in cover for charging the apparatus with
cast iron. T tuyeres.
When the operation is terminated and after balling, the cover P is removed, the
slag which is still liquid is run off and the apparatus oscillated about 180° degrees
in the direction of the arrow until the balls drop into a carriage placed in a trench
beneath the apparatus for the purpose of being conveyed to the hammer or the
press. The blooms produced may be rolled with or without being re-heated or
treated in the Martin furnace.
With the apparatus above described the cold blast may also be used and cast iron
which has been re-melted in the cupola, may be treated, the operation being per-
formed in the same way and the re-actions being similar.
All the above described operations may be performed in the Bessemer converter,
provided the position of the tuyeres be altered.)
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 apparatus for refining dephosphorizing and desulphurizing
crude cast iron as it comes from the blast furnace or for effecting any one of said
operations in the manner herein before specified, said apparatus being provided
with a double set of tuyeres, the lower set being directed upwards and situated at
the opposite side to the mouth and the upper set being situate above the level of
the bath as described.
2nd The employment for the purposes of this improved process, of the Bessemer
converter by modifying the arrangement of the tuyeres, by which the blast is
injected into as well as above the bath of metal as herein before specified.
3rd The herein described method of running the refined cast iron onto a basic
hearth for the purpose of converting it into steel by known means, as specified.
D
8011 1
T
1000