Apparatus therefor.
Year: 1887

page_text: Date of Application, 21st July, 1887
Complete Left, 19th May, 1888
Complete Accepted, 22nd June. 1888
Apparatus therefor.
We, H. C. BULL & COMPANY, Limited and HENRY CLAY BULL, Engineer, both of
31 Poultry, London do hereby declare the nature of the said invention to be as
follows:-
This Invention relates to the manufacture or production of metals from their ores,
such ores being in the form of oxides and capable of being reduced and smelted by
carbonic oxide and hydrogen. For instance it relates to the manufacture of iron and
steel copper and other metals from their ores and has for its object to effect their
production direct from the ore, that is, to produce iron and steel and other metals in a
form ready for use as a manufactured article by a single process and in one apparatus.
According to this Invention we employ a combined central reducing shaft and open
hearth furnaces, calcining ovens, air heating stoves and gas producers. These are
preferably of the type described in the Specifications accompanying the applications
for Letters Patent numbered 10203, 10204 and 10205 respectively, but the essential
feature connected with the gas producing apparatus and hot air stoves is that they
shall be capable of producing water gas of a high temperature and air of high
temperature respectively, these being important requisitions for rapidity and efficiency
of production. To secure these desiderata they are supplied with hot air when being
heated up, or revived, such hot air being supplied from the said hot air stoves.
The central shaft is filled with ore, coal and lime, the coal being preferably in the
form of brickets. The lime is provided in nearly sufficient quantities to neutralize
the silica of the ore and the coal may be provided at about five hundred weights to
the ton of metal in the ore. The charge is heated by hot gas and air which are drawn
through it by exhausting apparatus from suitably arranged air and gas mains. The gas
and air first pass through the open hearth furnaces and then through the charge of ore,
coal and lime in the shaft; the gas being in excess. These gases with the excess of gas
before mentioned reduce the ore to a metallic state; while the intense heat at the
bottom of the shaft melts the metal and the slag which run down into one of the
open hearth furnaces. Here additional lime, or other basic material is supplied to

page_text: make the slag thoroughly basic. If necessary iron ore may be added to further
oxidize any carbon, or phosphorous that may be in the metal. When the metal has
been treated for a certain time in the open hearth furnace and test pieces taken from
it show the required fracture spiegel, or ferro-manganese is added in order to produce
the kind of metal required. The charge is then tapped out and cast into ingots in
the ordinary way.
The working and tapping out will be conducted alternately in one,
or other of the open hearth furnaces. For a short time previously to adding the ferro-
manganese the flow of metal to the hearth will be stopped.. This may be effected by
the introduction of a dam of ganister, or fire clay into the duct between the shaft and
the open hearth furnace. The dam is preferably placed in position through a door
near the shaft. The degree of exhaustion is arranged to be sufficient to carry off the
waste gases and the gas and air are sent into the open hearth furnace at a sufficient
pressure to secure a slight outflow of them through the door apertures when they are
uncovered.
The lime is introduced into the open hearth furnaces in an intensely hot state and
fresh from a lime calcining oven; two of which are arranged conveniently for each
open hearth furnace. One of each set is kept out of service during which time any
necessary repairs connected with it may be effected. Before the ore and the lime are
charged into the reducing shaft they are calcined in a suitable calcining furnace placed
at the top of the shaft; and they are introduced into the shaft through an ordinary
cup and bell device-in a highly heated state. During the time the charge is being
introduced communication between the exhausting apparatus and the shaft is cut off.
This may be done by a suitable valve and by it immunity from explosions is secured.
A suitable arrangement and construction of apparatus for effecting the production
of metal as above specified consists as follows:-The reducing shaft is similar to an
ordinary blast furnace and is provided with a cup and bell for charging and an exhauster
for removing the waste gases. The internal shape may be of any approved kind. At
the bottom of the shaft two open hearthed furnaces are arranged preferably and for
convenience about thirty degrees in front of the centre line of the shaft. The open
hearth furnaces are provided with the usual doors on each side and the roof and
hearth are made removeable being built in separate metallic framework for this
purpose. The roof is provided with an opening through which lime, or other basic
material may be conveniently introduced. The hearth is made of basic material such
as lime, magnesia, or the like. The furnace may be supported by a hollow framework
on columns through which water is kept circulating. The furnace is provided with
hydraulic casting crane, which in addition to manipulating the casting ladle is arranged
and constructed for the purpose of removing, or replacing the top, or hearth of the
furnace when either need renewing, or repairing. The crane before mentioned swings
the ladle over the ingot moulds which are arranged in the casting pit. Hydraulic
cranes as usual in the Bessemer process are provided for moving the steel ingots to
trucks.
The above described elements form a harmonious whole consisting of a casting pit
provided with hydraulic cranes and ladle; open hearth furnaces entering into and
discharging their waste gases into a reducing shaft; a reducing shaft filled with coal,
ore and limestone, the coal converting the carbonic acid and vapour of water into
carbonic oxide and hydrogen, the ore being reduced by the gases, the limestone to
nearly neutralize the silica of the ore; a cup and bell and a valve to cut off com-
munication to the exhauster during charging and the exhauster to remove waste gases
and deliver a portion of same to the air heating stoves; and calcining ovens and
steam generators. By these means the work necessary to be done within the
reducing shaft is diminished and thereby the quantity of metal produced in a furnace
of a given size is largely increased. The coal used in the furnace is by preference in
the form of brickets by which the saving of the cost of making coke is effected and
the volatile gases which escape increase the waste gases in strength and volume. The
gases are therefore more suitable for the calcining oven the air heating stoves and
steam boilers. The air heating stoves through being supplied with hot dry gases
containing the maximum of combustible with the minimum of carbonic acid, due to

page_text: the calcining of ore and limestone, and being supplied with hot air which has been
previously heated in the neighbouring stoves, are capable of supplying air at a much
higher temperature than has been heretofore possible. The advantages of this intensely
heated air are firstly its use in the gas producers for the purpose of obtaining a liquid
cinder by which means it can be easily removed, thus ensuring continuous and satis-
factory working, the principal difficulty heretofore in this type of producers having
been their choking up in the bottom with cinder. The second advantage of this
intensely heated air is that we are enabled to maintain a steel melting heat in the open
hearth furnaces by only burning a portion of the gas introduced therein, the gas being
intensely hot owing to the producer being supplied with heated air.
Dated this 20th day of July 1887.

page_text: An Improved Process for Extracting Metals from their Ores and
Apparatus therefor.
We, H. C. BULL AND COMPANY, Limited, and HENRY CLAY BULL, Engineer, both
of 31 Poultry, London, do hereby declare the nature of the said invention 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 the manufacture or production of metals from their ores
such ores being in the form of oxides and capable of being reduced and smelted by
carbonic oxide and hydrogen. For instance it relates to the manufacture of iron and
steel, copper and other metals from their ores, and has for its object to effect their
production direct from the ore, that is to produce iron and steel and other metals, in a
form ready for use as a manufactured article-by a single process and in one apparatus.
But for the sake of simplicity the description of this Invention hereinafter given will
refer simply to the manufacture of Iron and Steel.
According to the Invention we employ a combined central reducing shaft and open
hearth furnaces, calcining ovens, air heating stoves and gas producers. These are
preferably of the type described in the Specifications accompanying the application for
Letters Patent No. 1020387 Calcining ovens, No. 10204 Air heating Stove, No. 1020587
Gas Producer respectively but the essential feature connected with the gas producing
apparatus and hot air stoves is that they shall be capable of producing water gas of a
high temperature and air of a high temperature respectively, these being important
To secure these
requisitions for rapidity and efficiency of production of metal.
desiderata they are supplied with hot air when being heated up or revived, such hot
air being supplied from the said hot air stoves.
gas
The central shaft is filled with ore, coal, and lime, the coal being preferably in the
form of brickets. The lime is provided in nearly sufficient quantities to neutralize the
silica of the ore and the coal may be provided at about five hundred weights to the ton
of metal in the ore. The charge is heated by hot gas and air which are drawn through
it by exhausting apparatus from suitably arranged air and mains. The gas and
air first pass through the open hearth furnaces and then through the charge of ore
coal and lime in the shaft, the gas being in excess. These gases with the excess of
gas just mentioned reduce the ore to a metallic state; while the intense heat at the
bottom of the shaft melts the metal and the slag which run down into one of the open
hearth furnaces. Here addition of lime or other basic material is supplied to make
the slag thoroughly basic. If necessary iron ore may be added to further oxidize any
carbon, or phosphorous that may be in the metal. When the metal has been treated
for a certain time in the open hearth furnace and test pieces taken from it show the
required fracture, spiegel eisen, or ferro-manganese or ferro-aluminium is added in
order to produce the kind of material required. The charge is then tapped and cast
into ingots in the ordinary way. The working and tapping out will be conducted

page_text: one of the open hearth furnaces in section.
Figure 2 is a plan half in full and half in cross section of the shaft and open hearth
furnace at Y Y Figure 1.
Figure 3 shows an open hearth furnace in transverse section through the line. X X
Figure 1 looking towards the shaft.
Figure 4 is a plan of an arrangement or disposition of the several parts of the
apparatus or plant.
Figure 5 is an end view of the arrangement of plant, and
Figure 6 is a front elevation of same.
The above Drawings are marked with figures and letters of reference corresponding
with those used in the following description like figures and letters being used to
denote like parts throughout the views.
The Drawings form a part of this Specification and together with the description
herein contained of this Invention are sufficient to enable others skilled in the art to
which it belongs to put the same into practice.
With reference to the Drawings, A is the reducing shaft, the main construction of
which is of known type, and is provided with a cup and bell charging device a³. An
annular bracket a supported upon columns a¹ is provided at the boshes to take the weight
of the upper part of the shaft this bracket is hollow and water is allowed to circulate
through it. a is the hollow water casing.
The two open hearth furnaces B are arranged as shown at about 30 degrees on each
side of the centre line of the shaft A. Communication is had between the shaft A and
the furnaces B by covered brick lined ducts or passages b. At the end of each duct
there is provided a door b' and an aperture 2 by which the dam of ganister or fire clay
above specified is inserted or removed as required.
The open hearth furnaces consist mainly of three portions; these are the moveable
cover c the body c¹ and the removable bottom c². The joint of the cover c and the
body c¹ is at c. Between the body c¹ and the bottom there is a water casing d;
this is provided to separate the body from the lining of the bottom which is
of basic material, such as lime, or magnesia. The bottoms of the hearths are
supported in position by screw jacks e. designates the usual furnace doors and g is

page_text: the door through the aperature g¹ of which the lime is introduced into the furnace ; or
this lime may be introduced in a regular stream by any known form of continuous
feeder. denotes the tapping spout and hole of the furnaces, and i and kare
respectively the hot air and hot gas mains (from the gas producers and air stoves D)
froin which alternate passages and ¹ (see Figure 2) for gas and air are led into the
furnaces. Suitable valves of a known type are used on each main to control the supply
of air and gas. The positions of these are shown in Figure 2 and designated and k³
and the handles for working them being also shown.
The pressure of the gas and air within the furnace B is maintained just above that of
the atmosphere so as to cause a slight outflow of the gases from the passages and
apertures of the doors when open and a tendency to do so at all times. By this means
no air other than the proper supply is drawn into the furnace at any time.
This regulation of pressure is effected by the controlling valves and of the air
and gas mains which are opened, or closed more or less. The only necessary conditions
are that the pressure kept in the air and gas mains shall be greater than the exhaustion
at the bottom of the reducing shaft, namely the passages b. The valves and k² are
also used to put the two furnaces B in and out of operation alternately as required.
This is done by closing or opening either one or the other of the two sets.
F represents a hydraulic casting crane of any known suitable kind, which in
addition to manipulating the casting ladle is so placed and arranged that it may serve
to remove or replace the cover c of the furnaces B when either need renewing, or
repairing. The crane F is arranged to swing the ladles f¹ over the ingot moulds
arranged in a casting pit in the ordinary way, and hydraulic cranes are provided to
move the steel ingots into trucks in the manner usual in the Besseiner process.
The lime required to be added to the metal and slag in the furnaces B is made from
limestone in calcining ovens G. Grouped with these ovens are other furnaces N
which are provided to smelt the spiegel eisen or other ferro metals specified required
for use in the open hearth furnaces B.
The gas producers C are arranged in two batteries one on either side of the plant,
and between these batteries are placed the air heating stoves D. The air stoves Dare
preferably of the type set forth in the Specification of our application for Patent
No. 1020487, but any equivalent stoves in which the air used to heat the stoves is
a portion of the hot air produced by the stoves may be used; and the gas producers C
are preferably of the type set forth in the Specification of our application for Patent
No. 102058, but any equivalent producers in which water gas from coal is made and
which hot air is used for reviving the producers may be used. Suitable mains, or
culverts communicate between the gas producers (, by which the hot air is led
to them, and culverts are also provided to lead hot air and gas to the open hearth
furnaces B from the hot air stoves and the gas producers: one of each of such air and
gas culverts are shown in Figure 1 and marked respectively i and k.
The cold air is supplied to the stoves D by an air pipe d from the blowing engines
stationed in the shed "H; the pressure of this air being only sufficient to pass through
the gas producers and air stoves and their passages.
The waste gases from the shaft A are led by a pipe partly to the air heating
stoves for use therein, partly to the calcining ovens E for use therein and partly
to the battery of steam generators J.
The gas and air as previously stated are drawn through the burden of the ore, fuel
and lime in the reducing shaft A and delivered to the steam generators J, air heating
stoves D and calcining ovens E by suitable exhausting engines, say of the "Root'
type shown and marked in Figure 5.
Between the shaft A and the exhauster A³ a valve is provided, and this valve
is closed during the charging of the shaft A with ore, coal and limestone as specified.
The waste gases from the steam generators J and air stoves and gas producers are led
to the chimney L.
In figures 5 and 6 the calcining ovens E are shown: these are two in number and
are worked alternately to prepare the ore and limestone before it is charged into the
ahaft A

page_text: The construction of these ovens is preferably that described in the Specification of
application for Patent for our Invention No. 10203/87 but it may be of any suitable
type.
The gas used in the calcining ovens is supplied from the waste gases from the
reducing shaft A.
The above described arrangement of apparatus forms a harmonious whole consisting
of a casting pit, provided with hydraulic cranes having ladles f₁, open hearth
furnaces B entering into and discharging their waste gases into a reducing shaft A
filled with coal, ore, and limestone, wherein the carbonic acid and vapour of water are
converted by the coal into carbonic oxide and hydrogen and the ore is reduced by the
gases, the silica of the ore being reduced by the limestone; a cup and bell charging
device a³ and a valve to cut off communication to the exhauster during charging, and
the exhauster to draw the gases through the furnace B and the charge in the shaft A
and to remove the waste gases and deliver a portion of same to the air heating
stoves D, calcining ovens E and steam generators J. By these means the work
necessary to be done within the reducing shaft is diminished and thereby the quantity
of metal produced in a furnace of a given size is largely increased.
The coal used in the furnace is by preference in the form of brickets by which the
saving of the cost of making coke and the volatile gases which escape, increase the
waste gases in strength and volume. The gases are therefore more suitable for
the calcining oven, the air heating stoves and steam generators. The air heating
stoves supplied with hot dry gases containing the maximum of combustible with
the minimum of carbonic acid, due to the calcination of ore and limestone, and being
supplied with hot air which has been previously heated in the neighbouring stoves,
are capable of supplying air at a higher temperature than has been heretofore
possible.
:
The advantages of this intensely heated air are firstly its use in the gas producers
for the purpose of obtaining a liquid cinder, by which it can be easily removed thus
ensuring continuous and satisfactory working the principal difficulty heretofore
in this type of producers having been their choking up in the bottom with cinder.
The second advantage of this intensely heated air is that we are enabled to maintain a
steel melting heat in the open hearth furnaces by only burning a portion of the gas
introduced therein, the gas being intensely hot owing to the producer being supplied
with heated air.
Having now particularly described and ascertained the nature of this Invention,
what we claim is :
1. The process herein described of extracting metals from their ores consisting
as a whole of the use in combination of the sub-processes, as follows that is to say :-
(1) Useing some of the air produced by the air heating stoves in heating up other of
such stoves and in revivifying, or heating up the gas producers whereby gas and air of
a high temperature are produced, (2) passing the air thus produced together with the
gas thus produced through an open hearth furnace or furnaces and an ore reducing
shaft in which coal is employed, and (3) using gas made in, or coming from the
reducing shaft to heat up the heating stoves and to heat and calcine the ore and
limestone used in such reducing shaft; all, as, or substantially as and for the purposes
set forth.
2. In processes of the type herein described of extracting metals from their ores, the
combined methods herein specified of controlling and working the gases of combustion
in the open hearth furnaces, and effecting the passage of the said gases through the
charge in the reducing shaft; which methods consist in maintaining and working the
air and gas in the air and gas mains (i and k) under pressure, and controlling and
maintaining the gases of combustion in the open hearth furnaces by valves (such as ??
and ) under a pressure slightly above that of the atmosphere, and causing the said
gases to pass through the reducing shaft by maintaining an exhaustion above the
charge in the reducing shaft by an exhausting engine (such as described), substantially
as and for the purposes set forth.

page_text: 3. In processes of the type herein described of extracting metals from their ores, in
which a basic slag is produced, the method herein specified of rendering the slag
thoroughly basic, which consists in adding lime to the metal and slag when in the
open hearth furnace, substantially as set forth.
4. The particular arrangement and combination of reducing shaft A and open
hearth furnaces herein specified and set forth with reference to the Drawings.
gas
The reducing shaft A, open hearth furnaces B, passages b, and air and
mains and with their accessory doors and other parts, constructed in combination
as set forth particularly with reference to Figures 1. 2 and 3 of the Drawings.
6. The open hearth furnace herein described consisting of the combination of a
moveable bottom c², a fixed body c¹ and a moveable top or roof c, arranged in
connection with the shaft A constructed and operating, substantially as and for the
purposes set forth.
7. The apparatus consisting essentially of the reducing shaft A, furnaces B, and
calcining ovens E, ladle crane F, air heating stoves D, and gas producer batteries C, C,
arranged as set forth with reference to Figures 4. 5 and 6 of the Drawings for the
purposes specified.