Improvements in the Manufacture of Iron and Steel.
Year: 1892

page_text: Date of Application, 29th Jan., 1892
Complete Specification Left, 22nd Oct., 1892-Accepted, 26th Nov., 1892
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Iron and Steel.
I, WILLIAM HUTCHINSON, of "The Ferns," Pennfields, Wolverhampton, in
the County of Stafford, Manager of Steel Works do hereby declare the nature of
this invention to be as follows:-
:-
In the manufacture of ingot iron and steel by the Bessemer process conducted
in vessels or converters having basic or neutral linings and also in the manufacture
of ingot iron and steel by the Siemens open hearth process conducted in furnaces
having basic or neutral linings the said processes are shortened and the yield of
iron or steel increased by the addition of oxide of iron to the molten iron under
treatment. The said oxide is decomposed its oxygen oxidising the impurities in
the iron. The oxidation products with the exception of the oxidised carbon pass
into the slag and the reduced iron increases the yield of the process.
In these processes, that is, the basic Bessemer and Siemens processes the quantity
of oxide of iron that can be advantageously employed depends upon the impurities
in the iron under treatment the reduction of the added oxide of iron being effected
solely by the impurities in iron capable of removal by oxidation.
My invention has for its object to increase the quantity of oxide of iron which
can be advantageously employed in the basic Bessemer and Siemens processes and
consists of the introduction of finely divided carbon or carbonaceous matter with
the air blast used in the Bessemer process and in the Siemens process the intro-
duction of finely divided carbon or carbonaceous matter with a blast of air or
preferably reducing gas. The carbon or carbonaceous matter which I preferably
employ is coke or charcoal or coal in fine powder. The said fine powder is intro-
duced into the tuyere or tuyeres by which the air or gas blast is delivered and is
carried by the said blast into the molten iron. The carbon becoming highly heated
acts as a powerful reducing agent combining with the oxygen of the added oxide
and liberating metallic iron which increases the yield of the
process.
By my invention the yield of the process is increased by the iron reduced by the
added carbon from the oxide in addition to the increase produced by the reduction.
of the oxide by the oxidisable impurities of the iron under treatment.
I sometimes treat oxide of iron alone in a suitable basic or neutral lined furnace
by injecting finely divided carbon or carbonaceous matter with air or preferably
reducing gas into the bath of molten oxide the object being to reduce the iron
from its oxide by the action of the carbon introduced.
Dated the 29th day of January 1892.
W. T. WHITEMAN,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Iron and Steel.
1 WILLIAM HUTCHINSON of "The Ferns" Pennfields, Wolverhampton in the
County of Stafford, Manager of Steel Works, do hereby declare the nature of my
invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
In the manufacture of ingot iron and steel by the Bessemer process conducted
in vessels or converters having basic or neutral linings and also in the manufacture
of ingot iron and steel by the Siemens open hearth process conducted in furnaces
having basic or neutral linings the said processes are shortened and the yield of
[Price 8d.1

page_text: iron or steel increased by the addition of oxide of iron to the molten iron under
treatment. The said oxide is decomposed, its oxygen oxidising the impurities in
the iron. The oxidation products with the exception of the oxidised carbon pass
into the slag and the reduced iron increases the yield of the process.
In these processes, that is, the basic Bessemer and Siemens processes, the quantity
of oxide of iron that can be advantageously employed depends upon the nature
and amount of the impurities in the iron under treatment, the reduction of the
added oxide of iron being effected solely by the impurities in the iron under
treatment capable of removal by oxidation.
My invention has for its object to increase the quantity of oxide of iron which
can be advantageously employed in the basic Bessemer and Siemens processes and
consists of the introduction of finely divided carbon or carbonaceous matter with
the air blast used in the Bessemer process; and in the Siemens process the intro-
duction of finely divided carbon or carbonaceous matter with a blast of air or
preferably reducing gas.
The carbon or carbonaceous matter which I preferably employ is coke or wood
charcoal or coal in fine powder.
The said fine powder is introduced into the tuyere or tuyeres by which the air or
gas blast is delivered and is carried by the said blast into the molten iron.
The carbon becoming highly heated acts as a powerful reducing agent combining
with the oxygen of the added oxide and liberating metallic iron which increases
the yield of the process.
By my invention the yield of the process is increased by the iron reduced by the
added carbon from the added oxide of iron in addition to the increase produced
by the reduction of the oxide of iron by the oxidisable impurities of the iron under
treatment.
I sometimes treat oxide, of iron alone in a Siemens basic or neutral lined furnace
by injecting finely divided carbon or carbonaceous matter with air or preferably
reducing gas into the bath of molten oxide the object being to reduce the iron from
its oxide by the action of the carbon introduced.
I will now proceed to describe with reference to the accompanying drawing the
manner of carrying my invention into effect.
The oxide of iron which I employ is preferably that obtained in the manufacture
of iron by the puddling process and known as puddler's tap cinder, but other oxides
of iron may be employed instead of or in conjunction with tap cinder such for
example as roll scale and tube scale or mill furnace cinder.
I do not however limit myself to the use of any particular oxide of iron, native
or artificial.
The carbon or carbonaceous matter which I prefer to employ, namely, coke or
wood charcoal or coal is reduced to a fine powder by crushing or grinding. The
powder is sieved by a sieve having about one thousand five hundred meshes to the
square inch and I employ the portion which has passed through the sieve. I do
not however limit myself to this particular degree of fineness. The powdered
carbon or carbonaceous matter may be introduced into the furnace by a blast of
atmospheric air or by a blast of reducing gas. I prefer a blast of reducing gas
such as is obtained in the apparatus commonly called a producer," the said
reducing gas being the result of the partial or imperfect combustion of coal or
coke effected by combustion in a partially closed chamber into which an insufficient
quantity of air to effect the complete combustion of the fuel is admitted.
The gas produced in the said "producer" consists essentially of carbonic oxide
and nitrogen and when heated has a powerful reducing and deoxidising tendency.
When it is inconvenient to employ a reducing gas, a blast of atmospheric air may
be employed, but in this case some of the powdered carbon or carbonaceous matter
is not utilised in the reduction of the oxide of iron but, is oxidised, the carbonic
oxide produced has however a reducing, action..
The quantity of powdered carbon, or carbonaceous, matter, I employ is in about
the ratio of one part by weight to three parts by weight of peroxide of iron..

page_text: Figure 1. of the accompanying drawing represents partly in elevation and partly
in vertical section an apparatus which may be employed for introducing the
powdered carbon or carbonaceous matter into the converter or furnace, and
Figure 2 represents the same partly in plan and partly in horizontal section.
a. is the blast pipe by which the blast of air or reducing gas is conveyed to the
perforated tuyere delivering it; b is a hopper containing the powdered carbon or
carbonaceous matter.
A horizontal passage c. connects the bottom of the hopper 6. with the blast
pipe a. In the said passage c. is an Archimedian screw or screw conveyor d. by
the rotation of which the powder is slowly transferred to the blast pipe a. On the
end of the prolonged axis of the screw d. a hand wheel e. is fixed by slowly turning
which the supply of the powder to the blast pipe a. is effected.
The iron to be treated together with the oxide of iron are introduced into a
Bessemer converter in the usual manner and the process of purification conducted
by turning first a blast of air without powdered carbon and after the carbon of the
iron has been removed as indicated by the setting in of the after blow, the finely
divided carbon or carbonaceous matter is introduced into the blast of air supplied
to the converter.
When I carry out my invention in the Siemens furnace I proceed in the ordinary
manner until most of the carbon of the pig iron has been oxydized. I then blow
into the metal by means of a blast of air or preferably reducing gas and the feeding
arrangement herein before described and illustrated, finely divided carbon or car-
bonaceous matter, tuyeres for carrying the blast below the surface of the metal
being arranged. I continue adding oxide of iron to the bath until a suitable
quantity of metal is obtained when the charge is tapped and cast in the usual
manner.
When I manufacture iron or steel by operating on oxide of iron alone, I reduce
the said oxide of iron by means of carbon or carbonaceous matter introduced, in
a finely divided state, into it by a blast of air or preferably reducing gas, the
said operation being conducted, preferably, in a Siemens furnace having a basic or
neutral lining.
Iron produced in either of the ways constituting my invention may be converted
into steel by the addition of the requisite amount of carbon preferably by the
employment of the alloys or compounds of manganese iron and carbon known as
spiegeleisen and ferro-manganese.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed, I declare that I claim
as my invention of "Improvements in the manufacture of iron and steel
"
First. The introduction of carbon or carbonaceous matter, in fine powder, into
the blast of atmospheric air or reducing gas, with which the mixture of pig or
cast iron and oxide of iron in the furnace is treated, the said carbon or carbonaceous
matter being introduced in the later stage of the process substantially in the
manner and for the purpose hereinbefore described.
Secondly, Treating molten oxide of iron alone with a blast of atmospheric air
or preferably reducing gas into which has been introduced carbon or carbonaceous
matter in fine powder substantially in the manner and for the purpose hereinbefore
described.
Dated the Twenty-first day of October 1802
WILLIAM HUTCHINSON.