Improvements in and relating to a Process of and Apparatus for Producing Steel Direct from the Ore.
Year: 1889

page_text: Date of Application, 4th June, 1889-Accepted, 7th Dec., 1889
COMPLETE SPECIFICATION.
Improvements in and relating to a Process of and Apparatus for
Producing Steel Direct from the Ore.
We, WILLIAM FITZ-CHARLES MASON MCCARTY, Engineer, residing at Number 501,
Seventh Street, North West, WILLIAM HENRY ASHTON, Gentleman, residing at
Number 3432 P Street, North West, and HERNAN DUDLEY WALBRIDGE, Gentleman,
residing at Number 902 Fourteenth Street, North West, all in the City and County
of Washington, District of Columbia, United States of America, do hereby declare
the nature of this invention and in what manner the same is to be performed, to be
particularly described and ascertained, in and by the following statement:-
Our invention consists in the process of and apparatus for producing steel direct
from the ore, and to obtain a full understanding of the process it should be stated
that heretofore it has been impossible to produce steel direct from the ore for many.
reasons, the principle one of which has been to keep the mass of ore and fuel separate
while being acted upon by the calorific energy of the burning fuel.
To carry out our process we have designed the apparatus as shown in the
accompanying drawings, in which:
Figure 1, is a transverse section of a blast furnace showing one manner of con-
structing the stack in which the bosh thereof is shown in spherical form, and connected
with the converter through a narrow passage way.
Figure 2, is a similar section of another manner of constructing the stack and
converter, showing the vacuum chamber also in section, and the preferred relation of
the air and gas heaters to the stack.
Figure 3, is a horizontal section through the line, X, X, Figure 2.
The stack may be of any usual or convenient constructior, provided at some distance
from the lower end with an annular offset, to support the charge of fuel and ore
introduced through the opening, D, near the top.
Below the offset is what we term the bosh, B, of the stack which communicates
through a central opening with the converter, A, below.
In Figure 1, the bosh is made in spherical form, and communicates with the con-
verter through a contracted passage-way, d, while in Figure 2. said bosh is made
in tapering cylindrical form, with its lower portion contracted to form the passage-
way between it and the converter.
The upper end of the stack has an outlet, a, for the gases and, products of combustion,
and has a side flue, P, controlled by a damper, , which can direct the products of
combustion either out at the tops, or into the side flue, P. the latter communicating
with the down-comer flue or pipe, 1, leading to the air heater or hot blast
producer, L.
On the opposite side of the stack is shown a heater, M, for heating the gases to be
used in working the charge.
The converter below the bosh of the stack communicates through a valve-pipe, m,
with a second converter or gas extractor, J, this pipe opening into the converter, A. at
some distance from the bottom, in order that the molten metal at the upper part
of the converter, A, may flow out as it is treated, into the gas extractor or
converter, J.
The gas extractor. J. communicates through a suitable opening. j. with a vacuum
chamber, K, or some equivalent device for producing a vacuum.
At different heights in the stack we provide suitable tuyeres for the introduction
into the charge at different zones of gas or gases, or combined air and gas, as
hereinafter described. The uppermost set, E. of tuyeres we prefer to arrange at
such a point that the gases introduced thereby may pass directly into the upper part
Dr

page_text: of the charge of ore, while the next lower set of tuyeres, 'F, is at some distance
above the offset,
.
A third set of tuyeres, G, are introduced just below the offset, e, and another set, H,
into the bosh of the stack, and a final set into the converter, A.
Formed in the interual wall of the stack and projecting therefrom, are a series of
shelves inclining.inward with their inner edges overhanging the ones next below, as
shown in Figure 2, or the stack is provided with a central wall, having shelves
projecting therefrom alternating with those projecting from the wall of the stack, the
edges of each overlapping the others, for a purpose hereinafter referred to.
In carrying out our process after the ore has been sorted, it is cracked up in sizes
suitable for the crusher, and after being crushed it is passed to the ore-mill to be
reduced to powder, when a proper charge thereof with sufficient flux and coke or
other fuel to start the operation is introduced into the stack through the charging
opening. D, and falls upon the shelving. Atmospheric air with carbonic oxide and
hydrogen are then introduced through the tuyeres, E, and ignited to start the fire.
Hydrogen and carbonic oxide are next introduced through the fuyeres, F. into the
body of the charge and also at H, if desired, until the mass is in a state of combustion.
we then introduce into the upper part of the charge through the tuyeres, E, pure
hydrogen gas to thoroughly deoxydize and reduce the ore by the removal of oxygen
and sulphur contained therein, leaving the iron in a free metallic state or spongy
.mass.
Although we have said that carbonic oxide should be introduced through the
intermediate tuyeres, F, G, H, with the hydrogen, we wish it to be understood that
the necessary carbon may be there introduced with the hydrogen by other means, for
instance, powdered carbon or liquid hydro carbon oil or carbonic oxide may be
introduced with the hydrogen, but we prefer carbonic oxide.
The relative proportions of hydrogen and carbon introduced through the intermediate
tuyeres will vary to some extent with the character of the ores under treatment.
As soon as the metal begins to fuse under the intense heat produced by the
introduction of the gases and air at different zones, as above described, the molien
metal will commence to fall down through the bosh into the converter, A. when the
pure hydrogen, and super-heated air are turned on through tuyeres. I, to decarbonize
and purify the molten metal, which has been partly acted upon by gases introduced
through the fuyeres, H, in its descent through the bosh, B, of the furnace.
The oxygen of the air and the hydrogen introduced into the molten metal in the
converter, A. produce an intense heat, and removes the silica and other impurities,
and a large portion of the carbon in the metal, and by regulating these gases
according to the nature of the ores under treatment, a pure homogeneous steel will be
produced.
In some instances, where it is found that the molten metal in the converier, A, has
not received sufficient carbon in its descent through the furnace, the proper proportion
of carbon in the form of finely divided graphite spiegeleisen with cyanogen and
air may be introduced through the inyeres. I.
When it is determined that the steel is of the desired quality the valve in the outlet
pipes, m. is opened and the overflow of the metal takes place into the second
receiver, J. When this chamber has been filled with sufficient metal for the run the
valve in the pipe, m, is closed and connection with the vacuum chamber is opened.
This will insure the withdrawal from the molten mass of any gases which may have
remained therein, homogeneous steel is then produced, free from the usual defects,
such as blow-holes. honey-combs, or other faults.
The operation, as will be readily seen, can be made continuous by connecting the
pipes, D. with a hopper which can be so arranged as to govern the supply so that a
continuous fusion is going on automatically, the metal falling in the form of ore and
flux minutely mixed from shelf to shelf of its own gravity, the shelves being arranged
on a proper incline, and the material falling in a continuous manner from shelf to
shelf while being heated by the gaseous fuel.

page_text: Having now particularly described and ascertained the nature of our said inveu-
tion and in what manner the same is to be performed we declare that what we
claim is
1. The process which consists in introducing into a highly heated charge of iron
ore and flux, hydrogen gas, and subsequently at different points into the charge
hydrogen and carbonaceous matter in a state of combustion, in order to melt and
subsequently carbonize the metal, substantially as set forth.
2. The process consisting in introducing into the highly heated charge of iron ore
and flux, hydrogen gas to reduce the ore, subsequently introducing hydrogen and
carbonaceous matter with air at different points into the same charge to melt the metal,
and finally introducing hydrogen and atmospheric air with or without carbon into the
molien metal to convert it into steel, substantially as set forth.
3. The process herein described of producing steel direct from the ore, said process
consisting in first reducing the ore by introducing pure hydrogen into the charge of
ore highly heated and flux, then introducing bydrogen and carbonaceous matter with
air or gas, to melt the metal, and subjecting the molten metal in its passage from the
stack to the converter, to the action of hydrogen and carbonaceous matter substantially
as described.
4. The herein described continuous process of producing steel direct from the ore.
said process consisting in first introducing hydrogen in the charge of highly heated
ore and flux to reduce the ore, then subjecting the charge to the action of hydrogen
and carbonaceous material with air, to melt the metal, then subjecting the molten
metal to the action of purifying gases and air, and finally subjecting the molten steel
thus produced to the action of a vacuum, substantially as set forth.
5. In an apparatus for producing steel direct from the
ore,
the combination with
the stack, having a series of tuyeres leading to different zones or belts thereof, and a
converter located below the bosh and connected therewith by a narrow passage,
whereby the molten metal may be withdrawn into the converter to be subsequently
treated. substantially as specified.
6. In an apparatus for producing steel direct from the ore, the combination with
the stack and converter, and the fuyeres for the introduction of the hydrogen and the
carbonaceous matter, of a second converter communicating with the first, and a vacuum
chamber communicating with the second converter, substantially as and for the
purpose specified.
7. In an apparatus for producing steel direct from the ore, the stack provided with
the inclined shelves or supports, with their inner edges overhanging the ones next
below, and the tuyeres for the introduction of the gaseous fluid, in the different zones
or belts of the stack, substantially as described. whereby the metal is caused to fall
from shelf to shelf while under the calorific energy of the gaseous fuel introduced
through the fuyeres, as set forth.
8. In an apparatus for producing steel direct from the ore, the stack and the con-
verter and the bosh located between the same, of flues communicating with the
converter and stack, substantially as and for the purpose set forth.
Dated this 4th day of June 1889
JENSEN & SON.
77, Chancery Lane, London, W.C., Patent Agents.