IMPROVEMENTS IN THE MEANS AND APPARATUS FOR 'PRODUCING. OR MANUFACTURING IRON, STEEL, AND OTHER METALS
Year: 1875

page_text: LETTERS PATENT to William Alexander Lyttle, of Woodstock Lodge,
The Grove, Hammersmith, in the County of Middlesex, Civil
Engineer, for the Invention of "IMPROVEMENTS IN THE MEANS AND
APPARATUS FOR 'PRODUCING. OR MANUFACTURING IRON, STEEL, AND OTHER
METALS."
Sealed the 2nd April 1875, and dated the 12th January 1875.
PROVISIONAL SPECIFICATION left by the said William Alexander
Lyttle at the Office of the Commissioners of Patents, with his
Petition, on the 12th January 1875.
".
I, WILLIAM ALEXANDER LYTTLE, of Woodstock Lodge, The Grove,
Hammersmith, in the County of Middlesex, Civil Engineer, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE
MEANS AND APPARATUS FOR PRODUCING OR MANUFACTURING IRON, STEEL, AND
OTHER METALS," to be as follows:-
-
The primary feature of this process consists in the incorporation of
the metallic ore in a crushed, powdered, or earthy state with the
ingredients necessary for the reduction only or for the reduction and
melting commonly designated "smelting" of such powdered ore, the
ID
071

page_text: or plastic state, and the proportion of fuel incorporated in the compound
may contain in carbon either the exact chemical equivalent for the
oxygen of the ore, or any less or greater proportion, including if desired,
and especially when the consolidation depends upon the plasticity of
clay, the entire fuel needed both for the deoxidation of the ore and the
production of the entire heat of the smelting process.
In
When bituminous coal or raw wet peat is incorporated with the com-
pound as the smelting fuel it is not necessary to coke it, though it may
be done by coking the compound when made in any of the various ways
now pursued for the manufacture of coke, and when the compound
contains the full supply of both reducing and smelting fuel in the form
of bituminous coal or peat it may either be moulded or shaped in any
desired way before coking, or it may be coked in mass like coal.
either case the cohesion of the compound during and after coking is
owing in the first instance to the cohesiveness of the plastic clay and
next to the glueing action of the coked fuel. Any clay or mud will
answer as the consolidating material for the aforesaid compound, and
where the addition of a larger proportion of silica than the clay or other
earthy matters contains is required it can be added in the form of
sand.
The clay, peat, or other earthy matter used for consolidation, and the
other ingredients of the compound, should be mixed in the manner
adopted generally by brickmakers, who use mixed materials for the
manufacturers of builders' bricks, and they may when pugged into the
required consistency, with the addition of such water as may be desired,
be shaped or moulded by any suitable brick machine into lumps. The
pugged compound may also be made to pass at once in continuous
worms or cylinders of any desired diameter from the bottom of the
pugging machine direct into the truck, which shall convey them either
to the coking oven or to the blast furnace. In either case and in any
case the moulded compound lumps or worms are prevented sticking
together in the furnace when any chance of such a contingency is feared
by sifting over them when being shaped either fine sand or the dust of
any fuel..

page_text: desirable to have recourse to any transfer of the damp or soft material
from the trucks into which it was delivered from the pugging or brick
machine until the lumps or worms are discharged into the furnace. This
summary method of dealing with the compound is a source of great
economy, and is a special feature both of novelty and advantage in my
process as regards its application to iron.
When the escaping gases of the furnace are to be used as heating fuel
it will be necessary to provide an intermediate chamber or other con-
densing apparatus, such as is used for separating the liquid or vapourized
constituents of coal gas at gas works in order that the moisture expelled
at the furnace top may be condensed and separated from the escaping
gases. An arrangement identical with that of a shower bath will answer
well for this purpose, consisting of a tower with the shower bath tank
for its roof. The escaping gas of the furnace enters at the bottom of
the tower and passes off to a gas holder from the side of the tower near
the top, and meets on its way upwards through the tower the descending
shower of cold water which condenses the steam, and which also by
moistening the caustic lime dust carried with the escaping gases leads
to the removal by the lime dust of all the injurious carbonic anhydride
present in the escaping gases. The carbonic anhydride forms calcic
carbonate with the caustic lime dust when moistened. The condensed
water of this tower is drawn off by any convenient syphon or other
drainage arrangement, which will hold back the furnace gases, and an
air-tight door is provided at the bottom of the tower for the periodical
removal of the intercepted dusi.
When the carbonaceous matter incorporated with the compound does
not contain enough fuel for the production of the smelting heat the
latter can be furnished by a separate supply of fuel interstratified with
the strata of the compound in the same way as the fuel is now charged
into the common iron blast furnace alternately with the fluxing lump
minerals and lump iron ore.
By providing silica in excess of the quantity which would most readily
combine with the lime and alumina of the fluxing ingredients of the
compound this silica will be reduced at the highest temperature, and by
thus combining as silicon with the iron when that metal is treated will
fit the resulting pig for any purpose in which such silicon is now deemed
needful. Under ordinary circumstances however pig iron or other metal

page_text: The only difference between this second branch of my process for
manufacturing metals from their ores, and that herein-before described,
lies in the circumstance that the reduced metal, chiefly iron, is not sub-
jected to fusion for collection in a furnace hearth, and that there is
therefore no special provision for the production of a fusible slag. When
crushed ore is mixed with lime for the making of the compound under
this method the carbonaceous matter may, if desired, be wholly omitted
from the consolidated mass, the reduction of the metal being then left
entirely dependent upon the reducing action of the carbonic oxide, and
when carbonaceous matter is mixed with a pure ore the lime may be
wholly left out. In all other respects the preparation of the compound is
the same as already described, but no silica should be added to the plastic
clay unless in the special contingency herein-after mentioned, and the
proportion of the clay employed should always be so much less than that
of the lime present as to increase the resistance, of the compound to fusion
by any accidental increase of the heat above the temperature barely
required for the deoxidation of the ore.
The distinction between this process and those which have preceded it,
for the purpose of making iron in a pure malleable form direct from the
ore is this, that all previous plans deal with the intermixed but not con-
solidated ingredients of the aforesaid compound, and they have therefore
necessitated the employment either of reverberatory furnaces or exter-

page_text: nally heated retorts as the slow and wasteful means of applying the
reducing heat. In this my new process, on the contrary, the heat acts
precisely as in the common blast furnace, the smelting of the contents
only being omitted.
The furnace employed may be of any height found useful in the
ordinary process of smelting. It be made of brick or in any way
may
""
found to answer for the construction of iron blast furnaces, but the
conical taper which it should have internally widening downward should
not be broken by that contraction called the "boshes in an iron blast
furnace until the point is reached at which the reducing flame of carbonic
oxide has its lowest entrance into the furnace. This carbonic oxide
flame may be produced in an adjacent furnace by blowing hot or cold air
through a deep stratum of red-hot coke, with or without an admixture
of superheated steam with the blast of, air in any of the well known ways
with or without hydrogen as an assisting product.
The carbonic oxide flame may be admitted not only at the bottom of
the furnace, or that portion of the furnace structure devoted to the
reduction of the ore, but also at any other points in the sides of the
reducing furnace. If the compound employed is fusible at a high tem-
perature the heat of the carbonic oxide must be kept down so as to
prevent the fusion of the compound.
The reducing furnace above described should be continued downward
as a vertical receiver, preferably but not necessarily of iron, and this
receiving cylinder of any desired depth should be filled with coke or
other dry, hard, broken material when the furnace is first put into blast.
A door made air-tight in any usual way is secured at the bottom of the
receiver, and no free oxygen should be allowed to enter the furnace
through the receiver. The bottom of the receiver may, if desired, be set
in a hollow, and hermetically sealed by water, which can be run off when
it is deemed necessary.
•
The bottom of the reducing furnace had better be at or near the level
of the ground, and the receiver, when used in the reduction of iron ore,
should be carried to as great a depth as possible below that level on
which the reducing furnace stands. Access to the bottom of the receiver
may be obtained by an inclined plane cutting, a hoisting apparatus, or
in any other convenient way.

page_text: There is nothing at all peculiar in the construction of this furnace and
receiver, which together, simply form a flue down which the compound is
passed whilst the carbonic oxide is passed upward. The only function
of the receiver is to admit of the periodical removal of the fixed products
of the receiving furnace in a cold state, and without the admission of
free oxygen to the reducing furnace. I do not therefore provide any
Drawings, because the foregoing description of the simple and well
known kind of apparatus required will amply suffice for the guidance of
any person skilled in the construction of iron furnaces. The reducing
furnace may in short be regarded as the common iron blast furnace
with all its parts cut off below where the belly ends and the boshes
begin.
In the case of metals which undergo volatilization on reduction to the
metallic state, like zinc, it is necessary to provide another receiving
chamber in air-tight connexion with the top of the furnace into which
the distilled metal shall pass with the waste gases and be condensed.
There are various receivers already in use for this purpose, particularly
in the manufacture of mercury, which if worked with the exclusion of
free oxygen and water in the case of highly oxidizable metals will answer
well for my purpose in connexion with the reducing furnace.
A settling chamber like that described in this Specification for the
separation of the watery vapour from the escaping gases of the smelting
furnace will answer well when mercury is the metal dealt with, and the
same arrangement with the substitution of heavy coal or other mineral
oil for the water of the shower bath will answer for the condensation of
the vapours of zinc or any other oxidizable metal. When the ores of
such metals are reduced under this process the compound containing
such ores must be perfectly dried when passed into the furnace under,
either the smelting or the direct method. The compound in such cases
had better always be baked and used when hot from the baking
oven.
The foregoing arrangement of receiving chamber for the condensation
of the vapours of distilled metals can also be fitted to the ordinary,
smelting furnace herein-before described when it is deemed desirable to
get rid of the earthy impurities of the ore by fusion into a slag. In
that case the reduction and volatilization of the metal in the lumps of
compound will take place at the upper part of the smelting furnace

page_text: whilst the lower part will be devoted to the production of carbonic oxide
and the fusion of the slag.
When the direct method is used for the reduction of the ores of metals
which volatilize the receiver descending from the bottom of the reducing
furnace will not be required for cooling reduced metal as when iron or
copper ores are so reduced, and it need not therefore be deeper than will
suffice for the removal of the waste materials of the furnace charge
without admission upward of free oxygen.
As regards the application of heat for the reduction of the compound
under this direct method, I do not confine myself solely to the internal
heat communicated to the lumps of compound by the upward current of
carbonic oxide, though this mode of applying the heat with carbonic
oxide is an essential feature of the direct method. External heat may
also be applied to the reducing furnace by making it as an iron shell
cased outside with brickwork, and having an intervening space, into
which the escaping carbonic oxide of the furnace may be conducted
down to any desired points, and burned between the iron shell above
mentioned and its surrounding casing of brickwork. This iron shell may
also be heated externally in any other desired way.
The receiver may also with much advantage be constructed of iron as
a cylinder descending from the furnace bottom, so as to accelerate by
radiation the cooling of the reduced metal when iron is dealt with, and
if the current of air forced or drawn by the usual pneumatic apparatus
for the production of the carbonic oxide is made to circulate on its way
to the fire through which it has to pass around the iron receiver such
air will become hot by absorbing heat from and cooling the contents of
the receiver.
When the proportions of lime and clay used in making the compound
for this direct method are those used in making common hydraulic
cement, namely, about two or three parts caustic lime to one part clay
thoroughly incorporated the reduced compound when withdrawn from
the bottom of the receiver will consist of metallic iron or other metal,
us sponge or powder, any excess of carbon which may have been used in
making the compound, and a powder possessing much of the character
of hydraulic or Portland cement.
If these powders are separated like chaff from grain by a winnowing
machine the reduced metal will be readily and perfectly separated from

page_text: the earthy and carbonaceous matter, and the latter can again be used as
the means of making a further supply of compound as a concrete in
precisely the same way as builders' concrete is made with hydraulic
cement and sand.
A woven screen should be provided, through which alone the blast of
the winnowing apparatus can pass, and this will stop all the light dusty
powder whilst letting out the blast. A similar arrangement is in use in
flour mills in connexion with the use of an exhausting fan for removing
the dust of the grain or flour without allowing it to escape with the
exhausted air.
A magnetic separator or arrangement of magnets like that used for
separating iron from brass filings may be employed to separate iron
when that metal is reduced in admixture with any other, as will occur
generally when this process is applied to the reduction of copper ores.
Calcined cupreous pyrites when smelted by this direct method gives
metallic iron and metallic copper in a powdered or spongy state. Under
any circumstances it is desirable to pass the reduced compound through
a mill or disintegrator, so as to break it to powder and thus facilitate the
separation of its component parts as described above.
Washing with a stream of water, as tin and other mineral ores are
separated from earthy or silicious matters by miners, will also answer to
separate the reduced metal from the non-metallic residue of the reduced
compound. When however the per-centage of earthy matter or gangue
in the ore is not very large it will not be indispensably necessary to
effect any separation of the metal, but in that case the compound must
be made with such a proportion of fluxes that the resulting reduced
product can be melted in any desired way after removal from the.
receiver. In that case a melting temperature calculated to agglomerate
the compound in the reducing furnace must be avoided. On the other
hand fusibility or fluxing character may not be imparted to the
compound until after its removal in a reduced state, when the requisite
addition of silicious or other suitable fluxing ingredients may be
incorporated with the reduced compound for the purpose of melting with
and covering the reduced metal when being subsequently melted or
otherwise heated for agglomeration into masses in a reverberatory or
other suitable furnace.

page_text: will be recovered
Under this direct method it is possible to produce iron impregnated
with carbon in any desired degree from that of steel to that of gray pig
iron or even spiegel eisen. This is easily accomplished by so com-
pounding the ingredients of the compound that they shall not be liable
to flux at a white heat, and by incorporating an excess of carbonaceous
matter with the iron ore. The compound thus prepared for this special
purpose must be reduced at a much more elevated temperature than
when malleable iron is required, the object of the increased heat as well
as of the excess of carbon in the compound being to promote the
immediate combination of the finely divided carbon with the nascent
iron in its sensitive spongy or finely powdered state.
As no free oxygen
will pass through the furnace the excess of carbon
when separated as already described from the iron in the reduced
compound, and the larger the quantity of carbon employed within
reasonable limits of bulk the less trouble will there be through the
fusion together of the particles of the reduced iron and the difficulty
thus presented to the separation of the metal from the earthy matter
when it is desired to do so. An excess of lime is an advantage in
carrying out this modification when ore is employed, which would be
likely to flux in its own gangue or earthy constituents. It is however
much more easy to consolidate the ore and carbon so that the compound
shall not flux, than it is to secure a mixture of ingredients in the
compound prepared for the aforesaid smelting method, which shall
always flux in a satisfactory manner. According to the heat employed
this mode of impregnating the reduced iron with carbon will produce a
metal which on being melted will be either pig iron or cast steel. By
limiting the proportion of carbon in the compound to that amount which
may be found on trial to be best suited for the purpose, steel only will
be the direct result of the reduction of the iron ore when a sufficiently
high temperature is employed.
Any desired proportions of lime and clay may be employed in the
direct method, the essential objects to be kept in view in addition to
those herein-before specified being the consolidation of the ore and
carbonaceous matter so as to admit of the passage of the carbonic oxide
blast through the contents of the furnace, and also the removal of the
sulphur present in the ore or fuel by the intermixed lime.
All the lime used in my process may with advantage be employed in
the caustic state for both the smelting and direct methods.

page_text: By charging the reduced iron made by the direct method without
impregnation by carbon into a molten bath of pig iron made by my
smelting method, with or without the admixture of spiegel eisen there-
with, any desired per-centage of carbon may be ensured in the fused
mixture from that per-centage, constituting a good common wrought
iron to any desired quality of steel.
""
The pure reduced iron may also be heated in a reverberatory furnace
and worked into a "E
bloom in the usual way, and will then furnish a
pure metal of great toughness.
When zinc, copper, antimony, or other metal is to be reduced to the
metallic state by means of this process the crushed ore, with or without
calcination, may also be incorporated advantageously with powdered
iron ore or ferric oxide in any desired proportion if iron is not naturally
combined with the zinc ore. By this means the iron of the ore which
becomes reduced at a low temperature in the compound acts as a
powerful auxiliary in the reduction of the zinc ore. For instance,
when a mixture of roasted iron ore or ferric oxide is made in the
compound with crushed zincic sulphide the iron when reduced takes
away the sulphur from the zinc by reason of its superior affinity for
the sulphur, and forms ferric sulphide. If lime is present in the com-
pound it also co-operates with the iron by desulphurizing that metal as
well as the zinc.
Instead of mixing ferric oxide with the zinc or other metallic oxide
or ore in making the compound for the smelting of zinc or other metal
by the direct method, reduced iron powder prepared under the direct
method may be used, and it is not necessary that such reduced iron
should be separated from the other mineral powders with which it is
mixed on removal from the bottom of the receiver herein-before
described.
Reduced iron powder with or without the admixture of carbonaceous
matter may also be employed, as above described, for the reduction of
the ores of copper, tin, and other metals having a weaker affinity for
oxygen or sulphur than the reduced iron made under this process.
When copper, tin, zinc, or lead ores containing sulphides of the metals
are to be respectively smelted under this process either by the smelting
or the direct method without previous calcination or roasting it is

page_text: desirable to mix with the powdered ore of each in making the compound
as much lime as will be suflicient to combine with and so remove the
whole of the sulphur which the ore may contain.
REFINEMENT BY OXIDATION OF SMELTED Metals.
When iron, copper, or antimony are smelted by the aforesaid smelting
method it will be necessary in most instances to complete their manu-
facture into the condition of refined metal so as to be fitted for
immediate further manufacturing applications. I propose therefore to
substitute for this purpose one uniform treatment of the above three
metals in lieu of the three or more distinct methods of refining by oxida-
tion of the crude metal now employed.
This aerater con-
My proposed arrangement for effecting this object consists merely in
a convenient and easily worked plan of burning out the impurities of
the molten metal by means of a blast of air forced downward into the
bath of crude metal through the following aerater.
sists of a metal tube the lower end of which is an inverted rectangular
box, hemisphere, or cone, intended to distribute the blast like the bell
of a trumpet, but two diametrically opposite sides of the rim of this
bell or box should be of unequal depths, each side being less in depth
than the remainder of same rim in order that when the blast is turned
on a rapid circulation of the molten metal may take place, as described
below.
The aerater should be protected by a covering of ganister or other
refractory material, and may with advantage be made with a water tube
casing like the water twyere of a blast furnace. The hearth of an
ordinary iron puddling furnace will answer as the receptacle of the
molten metal to be refined by this plan, because it will only be necessary
to make an opening in the roof of the furnace over the centre of the
hearth for the insertion and vertical play of the above-mentioned aerater.
An useful form for the bottom of this aerater is that of an inverted
rectangular box with the vertical blast tube rising from the centre of its
upturned bottom. The four sides of this box I shall designate A, B,
C, D, for the sake of description. The opposite sides A and C should
be of the same depth, but the other sides B and D should both be less
in depth than A and C. Moreover one of these two sides B and D, say
B, should be less in depth than the other D. The action of the blast

page_text: when this box is forced down into the molten metal will then be to drive
the metal out violently from the edge of the side B whilst other metal
must at the same time run in beneath the box in accordance with well
known hydrostatic principles underneath the side D. The larger this
box aerater is made the more speedy and efficient will be the refinement,
because the whole of the surface of molten metal underneath the box
will be subject to oxidation by contact with air, the pressure of which
will be exactly proportional, when the blast is strong enough, to the
depth to which the box is forced down into the bath of molten metal.
If the side B of the box is slightly indented on its lower edge of
ganister the ebullition of the metal caused by the escaping blast will be
the more broken and efficient, and by this extremely simple appendage
the common iron puddling furnace will acquire all the oxidating and
refining capacity of a special Bessemer converter. The vertical pipe
through which the blast is conveyed down to the metal below the
aerater may be sustained and moved in any desired ordinary way, the
only and easily realized conditions being that in its motions upwards or
downwards by rack and pinion gear, screw, or otherwise, it shall be
under control, and that a flexible or jointed air-tight tube connection be
provided to convey the air from any ordinary blowing apparatus into
the vertical tube of the aerater.
When the aerater is raised to the roof of or out of the puddling
furnace the metal can be melted by the flame of that furnace as at pre-
sent, if not tapped in from another furnace in a molten state, and the
melting flame of the puddling furnace may be continued, if desired,
whilst the aerating blast is at work.
In the case of iron the colour of the flame under the action of the
blast will indicate the degree of refinement, as in the Bessemer steel
process, and the complete Bessemer process of making steel can be
carried out by the use of this aerater as a substitute for the Bessemer
converter.
An economical plan of employing this aerating arrangement for the
manufacture of steel by the combined use of smelted or pig and reduced
iron made by the foregoing smelting and direct methods is to charge
the puddling furnace with pig iron, and when the temperature of this
molten pig has become very high under the joint action of the furnace
flame and the combustion of the carbon of the pig metal add powdered

page_text: malleable or pure reduced iron red hot so long as the fluidity of the
molten bath is not impaired thereby. By this means the reduced iron
is easily brought into a solid and homogeneous state, and by adding
either the required proportion of spiegel eisen to this bath, as in the
Bessemer process, or as much of the highly carbided reduced iron of
the foregoing direct method as may be found suitable, the result will
be the production of an iron or steel of any required degree of hardness.
When copper or antimony is refined by means of this aerating arrange-
ment the attainment of the required degree of. oxidation of impurities
is ascertained by the occasional withdrawal of samples for examination
as the aerating of the metal progresses.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Alexander Lyttle in the Great Seal Patent
Office on the 24th June 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ALEXANDER LYTTLE, of Woodstock Lodge, The Grove, Hammersmith,
in the County of Middlesex, Civil Engineer and Fellow of the Chemical
Society, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of January in the year
of our Lord One thousand eight hundred and seventy-five, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Alexander Lyttle, Her
special licence that I, the said William Alexander Lyttle, my
executors, administrators, and assigns, or such others as I, the said
William Alexander Lyttle, my executors, administrators, and assigns,
should at any time agree with, and no. others, from time to time and
at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle
of Man, an Invention for "IMPROVEMENTS IN THE MEANS AND APPARATUS
FOR PRODUCING OR MANUFACTURINg Iron, Steel, and Other Metals,” upon the
condition (amongst others) that I, the said William Alexander Lyttle,
my executors and administrators, by an instrument in writing under
"

page_text: my, or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the
Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Alexander Lyttle, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement:-
My Invention relates to processes and apparatus for producing iron
and other metals from their ores, either in a molten condition or in a
spongy or pulverulent condition, or, in the case of the more volatile
metals, in the state of vapour; also to the treatment of the spongy iron
so produced for the manufacture therefrom of malleable iron and steel,
and to the refinement by aeration of molten metals thus produced.
In the following description I shall divide the processes into two
sections, one of which I shall designate the smelting process, and the
other the reducing or direct process.
"
The former process applies to all metals which are produced in a
melted, otherwise called smelted state, whilst the latter relates to
the production of metals in a pulverulent condition without having
recourse to any preliminary stage of smelting or fusion.
Both the pro-
cesses can be made to apply to the manufacture of volatile metals like
zinc.
SMELTING PROCESS.
In this process I employ ore in a plastic or pulverulent condition, or
I crush the ore to a sandy consistency, and in order to facilitate such
grinding of the ore in some cases I heat or roast the ore, and plunge it
while hot into water, so that it becomes partially disintegrated by the
shock. I mix the plastic or crushed ore with any plastic earthy material,
such as clay, mud, peat, or sediment of sewage as a consolidating
medium, adding in some cases lime, partly to increase cohesion and
partly as a flux, also with such silicious or other materials as may be
found necessary to yield the requisite flux, and with powdered car-
bonaceous matter or fuel. This carbonaceous matter may be coal, coke,
peat, peat charcoal, or wood charcoal, and I prefer to select such matter,
as is comparatively free from phosphorus.

page_text: When the smelting heat and flame are not to be supplied from a
separate combustion chamber or carbonic oxide gas furnace, as hereafter
described, the quantity of carbonaceous matter incorporated with the
ore may be such as to suffice for the reduction of the ore, and also to
furnish by combustion the heat necessary for its reduction and fusion.
The fluxing materials are selected according to the nature of the ore
treated, so as to form with its non-metallic products a fusible slag, and
their quantity will depend also on the nature of the ore and on
the quantity, as well as chemical composition of the clay employed to
agglutinate the mixture. These ingredients are thoroughly mingled
together by any known method of pugging, so as to form a cohesive com-
pound like bricks in their moist condition, and the compound may be
moulded into bricks, or may be simply extruded in lumps of irregular
form and size from die holes in the bottom of the pug mill.
The bricks
or lumps of compound may be dried, but this is not necessary when they
are to be treated in a furnace such as I will presently describe; also
when bituminous coal or raw peat is employed as the carbonaceous
material the compound or the lumps thereof may be coked by heat like
ordinary coal, but this is also unnecessary. By dispensing with the dry-
ing or coking of the compound a large economy of time and of heating
power is effected.
⋅
The bricks or lumps of compound, prepared as above described, are
charged into a vertical furnace or cupola fed at the top, so that the hot
gases rising from the lower part of the furnace serve to dry and coke
the upper layers of compound before they reach the hot zone of the
furnace below.
The form of furnace which I prefer for smelting, according to this
process, is represented partly in section and partly in elevation at
Figure 1 of the accompanying Drawings, a sectional plan of the same
being shewn in the plane of the blast nozzles or tuyères at Figure 2.
This furnace is arranged for the purpose of keeping the fuel out of con-
tact with the material under treatment, the latter being exposed only
to the action of the gaseous products of combustion.
The central portion A, B, is the cupola or blast furnace in which the
smelting is effected. On each side of it at (and D is a chamber con-
taining the fuel, made to taper outwards towards the base, so that the
fuel may descend freely, and constructed of such height that the

page_text: adhesion of caked fuel to the lower part when' bituminous coal is used
may be overcome by the weight of the superincumbent mass of fuel.
These chambers are provided with covers F at the top, which are .
removed from time to time for charging with fuel, and replaced so as to
leave no opening for the escape of products of combustion at the top of
the fuel chamber.
Blasts of air are directed into the lower part of the fuel chambers, as
indicated by the arrows O, P, Q, R, in Figure 2, and the action of these
blasts is distributed uniformly over the mass of fuel at the bottom of the
chamber by means of a ring channel I of trough form in section, into
which the several tuyères are led. These blasts may be heated, but I
prefer generally to employ cold blasts.
The products of combustion from the mass of fuel burning at the
bottom of the chamber finding no escape upwards pass by the
passage K, L, into the cupola A, B, and the heat at the base of the
cupola may be intensified when required by additional blasts, as indi-
cated by the arrows diverging from A and B, Figure 2. The bottom of
each fuel chamber of this furnace may be carried down as a blind well
below the level of the plane of combustion in which the tuyères of the
blast are placed, and by providing this well with a side door and a
smooth floor inclined downwards towards the door at such an angle as
shall cause the contents to press in that direction the fuel contained
therein mixed with ash and clinkers may easily be periodically removed.
Not much of the contents of the well should be removed at one time,
otherwise the subsidence of the fuel in the chamber above may interfere
with the combustion in the circle of the blasts. The withdrawn fuel
can be picked and screened for future use. If the diameter of the well
is large two or more clearing doors at convenient points around its
bottom may be provided, together with a corresponding number of
inclined planes of flooring for shooting the contents to the several doors.
It is obvious that an arrangement or furnace, such as I have described,
may be employed for smelting or metal melting purposes generally, pre-
senting the advantage of keeping the fuel separate from the material
under treatment.
When an ordinary cupola or blast furnace is employed for treating, the
lumns on brinks and which Thav

page_text: of compound are charged in the usual way in alternate layers, when
the lumps are compounded with only the quantity of carbonaceous
matter necessary for reduction. If however they are compounded with
enough of such matter, not only for reduction, but also for furnishing
the fuel necessary for fusion, the layers of fuel may be dispensed with,
and in that case the lower part of the furnace is charged in the first
instance with fuel of an open character, such as coke, the combustion of
which serves to get up the heat and to dry the lumps of compound fed
in above, after which the combustion of the fuel contained in the red-hot
lower lumps suffices for the continuous working of the furnace without
the addition of separate supplies of fuel.
In the above description I have referred to cupolas or furnaces open at
the top, whence a large quantity of combustible gas will escape mixed
with steam, nitrogen, carbonic anhydride, and other gaseous products.
When it is desired to utilize for heating purposes the combustible gases
so escaping it is of advantage to separate from them the watery vapour
and carbonic anhydride, as well as to cleanse them from solid particles
suspended in them.
For this purpose I provide the top of the furnace
with any of the well-known arrangements, such as that designated the
“cup-and-cone" valve, by which it may be closed when charged; and I
fit the shaft immediately beneath this valve with the usual arrangement
of apertures connected with the main pipe, through which the escaping
furnace gases are now collected. This main pipe communicates with
the lower part of a tall chamber, in which a shower of cold water is
kept falling. The water condenses the steam and throws down the solid
impurities, and as a large portion of these consists of lime in a caustic
state a considerable proportion of the carbonic anhydride is absorbed by
combination with the wetted lime dust to form calcic carbonate. The
gaseous products thus to a large extent purified are conducted from the
upper part of the purifying chamber to be utilized for heating purposes.
There is a loss of sensible heat resulting from the cooling of the gases by
water, but this is more than counterbalanced by the important increase
in the calorific value of the gas due to the removal of carbonic anhydride,
and the use of this arrangement will be a gain, even when used with
an old blast furnace under the old smelting process. If the water
used is made milky with quicklime its efficiency in effecting the perfect
removal of the injurious carbonic anhydride is greatly increased, and as
all the lime taken up by the water in any way may be recovered as

page_text: sediment from the water which passes off from the bottom of the purify-
ing tower there is but little loss in the lime for this purpose.
Figure 3 represents a vertical section of a purifying chamber suitable
for operating as I have described. It consists of a tall chamber
surmounted by a cistern A from which water issues by nozzles or
perforated pipes S, T, V, arranged so as to spread it into a diffused
shower. The products of combustion from the furnace enter this
chamber by the lower pipe F and ascend in a direction opposite to that
of the descending streams of water, being finally conducted away by the
pipe E, H, K. A grating B, C, is with advantage placed in the chamber
to break up and distribute more completely the descending streams; and
by making this grating of double rows of bars so placed that the bars of
one row shall overlie the spaces between the bars of the lower row the
ascending gaseous currents are brought into more intimate contact with
the descending liquid. The water with the solid matter carried down
by it to the bottom of the chamber may filter away through a gravel
bed at the bottom or floor, a door C being provided for the removal from
time to time of the solid matter which is retained. Or the bottom of
this chamber may be made as a well and kept always filled with water,
which communicates by a short wholly submerged culvert of large
diameter from the bottom of the well to an adjacent pond. If the
culvert is well inclined downwards as it passes outward from the bottom
of the purifying tower to the bottom of the pond there will be no
obstruction by the intercepted dust of the furnace, which on drifting
down the culvert will form a sediment that can be dredged out of the
pond for further use. By having a number of ponds for the escaping
water of this purifying tower some can serve as coolers, whilst that
which has had its water most perfectly cooled is being made to supply
the water tank at the top of the tower. When this pond is thus emptied
its sediment of lime, ore, and carbon can be removed and used in making
the aforesaid compound. By this means very little water will be required
in working under my process, because the greater part of that used in
mixing and pugging the compound will be recovered as condensed steam
in the purifying tower, and the water of the cooling ponds will therefore
be of great value for steam boilers on account of its freedom from the
dissolved calcic carbonate, which injures such boilers by incrustation.
In dealing with the ores of volatile metals, such as zinc, either by the
smelting or the direct process, I adopt a like arrangement for the

page_text: purpose of condensing the metallic vapour that escapes with the gaseous
products of combustion from the furnace top, but in that case, although
water may sometimes be used as the condensing agent, it may be replaced
by a shower of heavy coal oil or other mineral oil so as to avoid oxidation
of the volatilized metal. For the same reason in treating such metals
I generally employ the before described lumps or bricks of compound
in a dried or baked condition before they are charged into the furnace
so as to generate as little vapour of water as possible. It tends to con-
dense the sublimed metal inside the furnace top.
REDUCING OR DIRECT PROCESS.
"
"
In the foregoing statement I have described the process for
smelting"
or obtaining metals from their ores in a molten condition, with separation
of their earthy impurities or gangue" as a fused slag, and also the
method of condensing the vapour of a volatile metal when produced by
the smelting process.
I will now describe the process by which I obtain metals from their
ores in a spongy or pulverulent condition without smelting or fusjon,
and also volatile metals in a state of vapour or sublimate with the least
amount of loss in the ore used.
The smelting and reducing processes are both applicable to iron, but
the former process only will produce that pig or fusible iron which alone
can be employed in the vast ironfounders' trade. On the other hand the
reducing process is better adapted than any other for the cheap pro-
duction of malleable iron and steel direct from ore
without any
intervening stages of smelting, refining, and puddling.
the means of obtaining metallic copper in a pure pulverulent state in one
single operation from its ore.
It also furnishes
In compounding the bricks or lumps for this purpose, as no fusible
slag is to be produced, the fluxes necessary for that purpose are not only
wholly omitted but avoided, and when lime is employed in the com-
pound the carbonaceous matter can also be omitted, the reduction of the
ore being effected, as I shall presently describe, wholly by the agency
of hot carbonic oxide gas.
Again, when carbonaceous matter is mixed with a metallic oxide or a
pure ore, that is, one free from sulphur and phosphorus, the lime may be
dispensed with, and when clay is employed as the agglutinating medium

page_text: for consolidating the compound care must be taken that if lime is
present it shall not be in such proportion as to form a fusible slag with
the silica and alumina of the clay and ore.
When compound is consolidated or agglutinated by means of clay
either for the smelting or reducing process there is a great waste of
labour if the clay and other ingredients of the compound are at once
pugged together with enough water to impart the requisite plasticity,
and I have discovered that this difficulty is completely solved by adding
the stiff unbroken lumps of natural clay to the dry powdered or crushed
ingredients of the compound so as to cause the complete disintegration
of the clay in the pug mill. The moisture of the clay is rapidly absorbed
by the dry ingredients as the mill works, and the clay becoming thus
reduced to powder is perfectly incorporated with the other ingredients
of the mill's charge. A perfectly homogeneous mixture is thus secured
with a considerable saving of power.
In order to secure uniformity of character in the compound all the
dry powdered materials should be proportioned and mixed in the same
way as is pursued in compounding the ingredients of the well known
London bricks used by builders, and then to add in the pug mill to a
given measure of this powdered mixture the required proportion of lump
clay.
The bricks or lumps of compound as already described, without any.
drying being required, are charged into a cupola or vertical blast furnace
of ordinary construction provided with a deep cooling receptacle at the
bottom, and without the usual contraction in its lower part called the
"boshes."
By several flues blasts of hot carbonic oxide mixed withi
nitrogen are forced into the bottom of this furnace at two or more of its
opposite sides, and this mixture of red hot gases or flame passes up
through the charge of lumps of compound in the furnace in the same
manner as described in the smelting process. These blasts of flame are
produced in adjacent combustion chambers or gas producers in whichi
there is a deep pile of coke or other suitable fuel. Air, hot or cold, is
blown in at the bottom of each such pile to support combustion, and the
products of this combustion rising through the pile of fuel issue from
its top in a highly heated state when they enter the bottom of the blast
furnace as above described.
Figure 4 represents partly a vertical section and partly an elevation of
a furnace suitable for the operation above described with gas or flame

page_text: producers, shewn at one side thereof, a set of similar producers being
provided at the opposite side, and also other sets at any other points
around the circumference of the furnace if such should be found
needful. The gas producers consist of two tall chambers or shafts H J,
and FG, the former provided with a hollow ring D E L, like that already
described in reference to Figure 1, with tuyères set in the hollow ring
through which blasts are forced into the chamber and diffused by the
ring channel around the bottom of the column of fuel which the chamber
contains. Both the chambers F G and H J are filled with fuel, that
used in the chamber F G being always coke, anthracite, or charcoal, and
that contained in H J being ignited at the bottom and subjected to the
blast. These chambers being closed at the top the products of com-
bustion from the fuel burning in H J are forced by the pressure of the
blast through the passages C, C', into the reducing furnace A B, which
is charged with the lumps or bricks of compound.
These gaseous pro-
ducts in passing through the coke or charcoal at the bottom of F G, at
a high temperature, have the carbonic anhydride which they contain
converted into carbonic oxide, which along with the nitrogen of the blast
enters the chamber A B as the deoxidizing vehicle, by means of which
the reducing heat is directly imparted to the charge of compounded
lumps. The bottom of the furnace A B is extended downwards,
terminating in an iron cylinder or well R K, where the contents of the
furnace undergo cooling as they descend below the flame passages C, T.
For the purpose of more effectually cooling this well and at the same
time utilizing a portion of the heat given off by it, I prefer to enclose it
in an outer casing which may be of brickwork or masonry, as shewn in
the Drawing, and in the cylindrical space surrounding the well or iron
cylinder inside the brickwork casing I fit a helical partition or screw. I
force a blast of air into the lower convolution of the helical passage thus
formed, and the air whilst it passes upward round the cylinder cools it
and becomes itself increasingly heated, finally passing by a pipe W to
the furnaces for producing the carbonic oxide, which furnaces it then
enters through the tuyères D, E, as a hot blast.
The hot carbonic oxide entering the furnace A B, acts both by its heat
and by its reducing qualities on the ore in the compound, which becomes
reduced and descends in a spongy or pulverulent condition when not
volatile along with the other ingredients of the compound into the
cylinder R K, where the whole becomes cooled without access of air.

page_text: Portions of the cooled matter are removed from time to time through a
door Z which is thereupon tightly closed.
For the treatment of ores which become reduced at moderate tem-
peratures, the heat of the flame or carbonic oxide blast should be kept
proportionally low, and generally except in the case of volatile metals it
must be below the fusing point of the metal under treatment.
When the carbonaceous matter mixed with the compounded ore
contains slightly more than the proportion of carbon, chemically
equivalent to the work of removing the whole of the oxygen, combined
with the metal of the ore, it is no longer necessary to provide a flame
rich in carbonic oxide, the only conditions of the flame then being that
it shall contain no free oxygen, and that its temperature shall be
sufficient as well as its volume for the required reducing heat.
By this
means a very much smaller quantity of fuel will have to be consumed
in the side furnaces, and one fuel chamber constructed and worked in
precisely the same manner as the chamber D, Figure 1, described in
the foregoing smelting process, will answer as a perfect substitute for
the two shafts FG, H J, Figure 4.
By a suitable regulation of the blasts under this modification as
already described, the flame may be made the vehicle for imparting
directly to the compounded lumps in a sensible form almost the whole
of the heat generated by the fuel consumed, and the reducing work will
fall wholly on the intermixed carbon of the compounded lumps. The
proportions of carbonaceous matter in the compound and of carbonic
oxide in the flame, may be varied in any degree with relation to each
other, and when the compound contains a moderately pure ore with
caustic lime intermixed, the carbonaceous matter may, as already stated,
be wholly supplanted by using a flame rich in carbonic oxide.
When
the ores. of volatile metals are thus treated, or of metals like copper
which are not highly sensitive to oxygen at a moderate heat when in the
freshy reduced pulverulent state, the cooling apparatus may be greatly
reduced in size as compared with that needed for the treatment of iron
ore, or it may, with volatile metals, be wholly dispensed with.
Instead of extending the cooling cylinder R K of the reducing
furnace downwards to a considerable depth, as shewn in Figure 4, it
may be constructed, as shewn in Figure 5, with a bottom tapering to a
small-outlet governed by a throttle, or preferably a slide valve, at E.

page_text: The flues for admitting the flame are shewn at the sides of B, Figure 5,
and the taper or contraction of the bottom is made to commence at some
distance lower down in order to protect from the direct action of the
flame an arrangement of rotary crushing fire-bars C, D. These fire-
bars are intended to bear not only the superincumbent dead weight of
the contents of the furnace, and so prevent the jamming or choking of
the tapering outlet, but also to serve as crushing rollers when rotated,
so as to break the remaining lumps for gradual discharge through the
valve E. These fire-bars C, D, have the shape of a cross in their trans-
verse section, as shewn more clearly in Figure 6, or they may carry pro-
jecting ribs, but as fine crushing is not needed, it is not desirable that
the ribs should touch as the bars revolve, and this condition is met by
means of the spur wheel gearing B', Figure 6, by which the bars are
made to revolve together without contact. This spur wheel gearing is
fitted upon the ends of the fire-bars, the latter being carried through a
horizontal opening in one side of the furnace for the purpose, and an
air-tight casing is provided outside to contain the wheel gearing and
perfectly exclude the air from the opening through which the fire-bars
project. Through this casing one driving shaft enters by a gland
packed to exclude air, and is made to propel the spur wheel gearing
slowly when required for discharging the contents. The fragments or
powder issuing from the passage E are received in trucks or vessels that
can be tightly closed, and removed successively to a position where they
are allowed to cool. In order to prevent oxidation of the reduced metal
by air when this transfer into trucks or vessels is taking place it is
desirable that the man in charge of the work should be provided with
an injecting syringe or oil can filled with cheap coal oil or petroleum,
and squirt a small quantity into the opening in the top of the receiving
vessel or truck which fits to the passage E. He should do this not
only before the discharging from E commences, but also whenever he
observes that the ignited vapour of the oil is not keeping the junction
between E and the mouth of the vessel encircled with a ring of flame.
The red hot contents falling on the oil in the receiving vessel causes it
to flash into gas, which expels the whole of the air.
"
39
The cooled matter removed from the reducing furnace consists of the
earthy impurities or gangue of the ore, redundant carbon, with
burned clay and any lime which may have been added, together with
the reduced metal, when not volatile, interspersed throughout the mass.

page_text: In order to separate the metallic dust I grind the fragments of com-
pound in any convenient way, and pass the mixed dust through a
winnowing apparatus precisely like that used for cleaning grain from
its chaff. Under this treatment the lighter particles of carbon are
carried to the greatest distance by the force of the blast, whilst the
other materials fall at distances inversely proportional to their, specific
gravities, and the metal is found by itself in a heap close to the winnow-
ing machine.
In order to prevent the waste of the lighter particles the chamber in
which the winnowing is conducted is provided with a woven screen at
the end furthest from the machine or blast, and this screen whilst giving
free egress to the air intercepts the fine dust.
Washing in a running stream of water, as is practised in cleansing the
ore of tin, will also answer as the means of separating the reduced
metal, but is not so economical, and is not so suitable to metals like
pulverulent reduced iron, which is highly susceptible to oxidation by air
and moisture.
When an ore of zinc, copper, or other metal containing sulphur is to
be treated in accordance with this reducing process, it is advantageous to
intermix iron ore in powder with the crushed ore of the metal required,
and to use such a proportion of the iron ore in making the compound,
as already described, that more than enough metallic iron shall be pre-
sent to form ferric sulphide with the whole of the sulphur of the other
intermixed ore. The iron is reduced at such a low temperature that
the powdered iron asserts its superior affinity for sulphur, and thus
greatly accelerates the reduction of the other metal in a pure state.
Pulverulent iron reduced, as before stated, after or without being
cleansed by the winnowing blast, may also be substituted for iron ore in
removing the sulphur contained in the ores of other metals; and such
iron powder may also be employed in making the compound to assist
or wholly replace carbonaceous matter as the means of deoxidizing and
desulphurizing other metals whose affinities for oxygen or sulphur are
less than that of iron.
I take a further advantage of this powerful affinity which iron has for
sulphur at a red heat in order to obtain metals from their chlorides by
either the smelting or the reducing process; but in this case, as I am
about to describe, the iron acts only through its reduction of the sulphide

page_text: of an intermediate or third metal, which must be intermixed with the
compound. In this further application of the same principle the chloride
of the required metal which has to be brought to the metallic state is
powdered finely and intermixed in making the aforesaid compounded
lumps with carbonaceous matter, iron ore, or pulverulent reduced iron,
and sulphide of calcium or sodium, the latter salt being employed in
such proportion that the calcium or sodium present may be something
more than sufficient to combine with all the chlorine contained in the
chloride of the required metal. The iron ore or iron in a reduced state
must also be intermixed in such combining proportion that it shall
amply suffice for the complete removal of the sulphur combined with the
calcium or sodium employed; but if this reaction is to take place under
my smelting process an excess of iron must be avoided in order to ensure
the fusibility of the ferric sulphide as the work proceeds. In the
reducing process however it is better to allow an excess of iron in order
to produce a less fusible or powdered sulphide of that metal. The
carbonaceous matter intermixed is for the same purpose as when iron
ore alone is treated for the production of that metal, and it may be
used in any quantity, or wholly replaced by carbonic oxide, as already
described.
Under this threefold reaction the iron at a red heat asserts its power-
ful affinity for the sulphur, and thus so far relaxes the bond of chemical
union between the sulphur and the sodium or the calcium that the latter
metals are free to exert upon the chloride of the required metal their
intense affinity for chlorine. I am assuming of course that in all cases
the required metal has, as usual, a much more feeble affinity for chlorine
than that element has for sodium or calcium. The result of the reaction
. will be the required metal in a pulverulent or sublimed state, and a
sulphide of iron, with chloride of sodium or calcium absorbed by fusion
in the mass.
A double chloride of the required metal, with sodium, or
with any other suitable metal for making such a double chloride, may
also be employed, as is now done in producing magnesium and
aluminium. When however the chloride of the required metal is con-
veniently volatile the compound may be made for this threefold reaction
as last described, but without the admixture of the chloride of such
required metal, and the latter may be introduced near the bottom of the
reducing or smelting furnace shaft by means of a hopper, or as a
sublimed vapour admitted through an aperture from an adjacent retort

page_text: "
"
or producer. This vapour, of chloride penetrates the compounded lumps,
and the above reactions follow. When chloride of aluminum is thus
sublimed with carbonic oxide flame through compounded lumps of the
above composition, to which a copper oxide or reduced copper is super-
added, the well known aluminum bronze is, with greater or less success,
the result, according to the care taken with the heat and proportions
under well known chemical rules. When ores of iron are treated
according to the reducing process the product is pure iron in a
pulverulent or spongy condition, which can be "balled " in a
reverberatory furnace to produce malleable iron, or fused in a bath of
molten pig iron to produce steel. If however such ores be compounded
with an excess of carbonaceous matter, and the exposure to a red hent
in the furnace be prolonged, the iron produced in the lumps by deoxida-
tion, as described, will undergo a process of " cementation," absorbing
carbon, so as to pass into the same condition as malleable iron which has
been converted by like cementation with charcoal into "blister steel."
In like manner spongy or pulverulent iron, no matter by what means or
process it may be produced, can thus be converted into steel by making
it up into lumps with carbonaceous matter, and exposing the lumps to
the direct action of the deoxidizing gases or flame, as above described.
When the lumps so exposed to flame are removed from the reducing
furnace, and have the metal thoroughly separated from all redundant
carbon by washing or winnowing, the powdered metal so separated is
made up into lumps with plastic fluxing materials, as already described
in the foregoing smelting process, but without carbon, and subjected to
an intense heat in a vertical blast furnace, or in a reverberatory or
other furnace in which the heat of fusion is so applied that no solid
carbonaceous matter can come into contact with the metal of the lumps.
The powdered metal thus fused as cast steel, which can be run into ingot
or other moulds in the usual way.
In compounding the powdered blister steel, or cementation steel and
plastic fluxes without carbon for this final operation of melting into cast
steel the fluxes should be so proportioned that their fusible point is
slightly above that of the powdered steel.
The furnace described in reference to Figures 1 and 2 is suitable for
such steel melting, as it provides the heat without contact of the fuel.
As already stated with reference to the reduction of zinc, a mixture

page_text: of ferric oxide or iron ore or pulverulent metallic iron may be used with
the sulphide of any other metal as a means of removing the whole of
the sulphur from such other metal when the compound containing these
materials is subjected to heat. The result of the reduction of this
mixture when the metal sought is not volatile is that the required metal
is freed from its combined sulphur, but is not yet available for separation
from the intermixed iron which now exists as ferric sulphide. In order
to effect this separation the mixture is next subjected to calcination in
the manner now well known for expelling and recovering the sulphur
contained in cupreous pyrites, and the resulting oxides of iron and the
required metal under treatment being again compounded into lumps with
carbonaceous matter is again subjected to reduction, as already
described. The product of this reduction is metallic iron and the other
required metal in a pulverulent state, and these metals, when the iron
alone is magnetic, can easily be separated by means of any of the well-
known magnetic separators which are used for separating the brass
from the iron filings of workshops.
The calcination of ferric sulphide in admixture as above with any
required metal for the purpose of subsequently reducing together in
this way the oxides of both metals may be conducted on a large and
continuous scale by compounding the mixture, without carbon, into
Jumps with the smallest possible quantity of agglutinating clay, charg-
ing the lumps into a furnace like that described in reference to Figure
4, and subjecting them in their descent to a flame of a highly oxidizing
character produced by excess of blast. The gases escaping from the
top of this furnace will be available for the manufacture of sulphuric
acid or sodic sulphate by direct action on chloride of sodium, and the
calcined contents are withdrawn from the furnace bottom, no cooling
receiver being in that case needed.
REFINING THE MOLTEN METALS.
"
When a bath of molten copper is exposed to the air in the course of
manufacture it absorbs oxygen, and becomes what is called dry"
metal. In order to render this "dry" copper tough, and therefore fit
for sale, it is subjected to the reducing action of the gases evolved by
a branch of green wood with which it is stirred until the required tough-
ness has been attained. I accomplish this same deoxidizing result by
means of any hydrocarbon gas or vapour injected into the molten copper
by means of the aerator described below, and the same aerator without

page_text: any alteration answers for the refining of pig iron and antimony by
oxidation, atmospheric air instead of hydrocarbon gas being injected
by the aerator into the molten metal. The same apparatus can also be
employed for the refinement of metals generally in the manner herein
described, no matter by what process such metals may have been
produced.
The aerating apparatus to which I refer is shewn in vertical section at
Figure 7. It consists of a pipe T cased with refractory material or a
water jacketing like that used in water tuyères, and widened out rectan-
gularly at the mouth so as to present four lips or sides B, C, D, one of
which B is shorter than that which is opposite to it D; the two other
sides C, which are opposite each other, being of equal depth, and both
deeper than D. This rectangular mouth-piece or inverted box is
immersed vertically into a bath of molten metal so that its lips are all
below the surface 'M, P, of the metal, and either a blast of air or of a
hydrocarbon gas or vapour. is forced at any desired degree of pressure
down the pipe T. The gaseous fluid thus blown down upon the metal
bubbles through it under the lip B, and thus causes a rapid circulation of
the metal by establishing a current, as indicated by the arrows, into the
aerator underneath D and out at B. This action is in accordance with
a well-known hydrostatic law, and by its means the metal is not only
subjected to the action of the gas blown through it at any desired
pressure, but is speedily as well as equally treated owing to the rapid
circulation thus induced.
The mouth-piece of the aerator may be of any desired shapė, rectan-
gular, hemispherical, or oval, so long as the same provision of two
unequal opposite sides is made for the above purpose, and the larger its
area is so much the greater is its efficiency, in consequence of the greater
surface of metal exposed to the blast or gas, the pressure of which is
proportional to the depth of the aerator's immersion in the metal. It is
obvious that this aerating apparatus can-be applied to the bath of metal
in the hearth of a reverberatory or common old puddling furnace, as
when the metal is fused therein the aerator can be lowered down from or
through the roof of the furnace into the molten metal, and that the
aeration of pig iron can thus be effected for the manufacture of steel
therefrom under the Bessemer process without the use of those costly
separate appliances for that purpose-known-as-"Bessemer converters."
A similar mode of applying the aerator can be followed in refining
antimony and copper, the air blast in the latter case being replaced by
33.

page_text: hydrocarbon gas or vapour, or by the gas produced by the burning of
carbonaceous matter in which the whole of the oxygen present is in
combination with carbon as carbonic oxide. If found needful the heat
of the bath of molten metal may be augmented by exposing its free
surface to the action of the reverberatory flame whilst the aerator is
immersed and in action.
Reserving to myself the right of modifying the details of the several
processes and apparatus which I have described, I claim as my
Invention,-
Firstly. The method substantially as herein-before described of smelt-
ing metals from their ores by compounding the ores along with suitable
fluxes and carbonaceous ingredients into bricks or lumps, and charging
these into a vertical cupola or blast furnace, where they are subjected
to the heat necessary for smelting.
Secondly. The smelting furnace for other metals as well as pig iron,
substantially as described in reference to Figures 1 and 2, consisting of
a central cupola charged with the ore or metal compound and lateral
fuel chambers where the combustion of the fuel is effected without its
admixture with the materials under treatment.
Thirdly. The method substantially as herein described of reducing
metallic ores without fusing or smelting the metal, by exposing bricks
or lumps compounded of crushed, earthy, or sandy ore, carbonaceous
matter and clay, or other agglutinating material, as specified, to the
action of a non-oxidizing or of a deoxidizing flame, and cooling the
lumps so treated before exposure to the atmosphere when the ore thus
reduced is not that of a volatile metal.
Fourthly. The method of reducing metallic ores last claimed, with
this modification, that carbonaceous matter is wholly omitted from the
compound when crushed ore is used, the reduction being effected entirely
by a flame rich in carbonic oxide, also the reduction of calcined
uncrushed natural lump ore in this way by carbonic oxide flame, when
and so long as such reduction is effected in conjunction with the use of
the method of separating the mineral impurities of the ore by winnow-
ing, as herein-before specified and hereafter claimed.

page_text: Fifthly. The reducing furnace, substantially as described in reference
to Figures 4, 5, and 6, consisting of a reducing chamber with lateral
fuel chambers for the production of the reducing gases.
Sixthly. The method substantially as herein described of separating
reduced metal in a spongy or pulverulent.condition from the earthy and
other non-metallic matter of the aforesaid lumps after their reduction
by pulverising the product of the reducing furnace and winnowing the
same.
Seventhly. The method substantially as herein described of producing
steel direct from iron ore, or from spongy or pulverulent iron, by exposing
the compound of ore or iron and carbonaceous matter to cementation in
the reducing furnace, or in any vertical blast furnace in which the heat
is not obliged to act upon the metal and carbon by radiation through
the sides of the furnace, but is imparted by the direct permeation of a
non-oxidizing flame blown upwards through the charge of compounded
lumps. Also compounding the powdered steel thus produced into lumps
with fluxing ingredients only, as described, and fusing the same into
cast steel in a blast furnace without contact of carbonaceous solid fuel.
Eighthly. The aerating apparatus as described in reference to Figure 7
for refining fused metal by causing a blast or oxidizing or deoxidizing
gas to press upon the metal, and to bubble through the same in such a
manner as to create a current of the molten metal across the mouth of
the aerating apparatus, substantially as herein-before specified.
Ninethly. The method substantially as herein described of freeing the
escaping gases of any blast furnace from carbonic anhydride by means
of a shower of water, used as specified in reference to Figure 3, with or
without an admixture of the milk of caustic lime, such water leading to
the absorption and removal of the carbonic anhydride either by its con-
tained milk of lime or by moistening and intercepting the lime dust
escaping with the gases of the furnace.
Tenthly. The method substantially as herein described of disinte-
grating stiff natural lump clay by pugging it with the dry crushed ore
and any other powdered matter required in making the compound, the
needful plasticity being then subsequently imparted by adding water to
the thoroughly intermixed mass.
Eleventhly. The method substantially. as herein described of exclud-
ing air from the receiving vessels, into which are transferred the red

page_text: hot contents of the furnace under my reducing process by means of
hydrocarbon oil introduced in such vessels.
Twelfthly. The method substantially as herein described of manu-
facturing zinc, copper, and other metals under my reducing process by
incorporating iron ore or pulverulent reduced iron with the ore of the
required metal to be reduced, in order to facilitate the reduction of such
required metal in a pure state; also by adding to this iron ore or reduced
iron as an additional auxiliary element of the compound powdered
sulphide of sodium or calcium when the required metal is to be reduced
from its chloride in an intermixed or sublimed condition, as herein-before
specified.
In witness whereof, I, the said William Alexander Lyttle, have
W. A. LYTTLE. (L.s.)