Improvements in Processes and Apparatus for Reducing Metals from their Ores, and for Obtaining Carbides, Acetylene, Cyanogen, Cyanides, Nitrides, and for Fixing Nitrogen.
Year: 1896

page_text: Date of Application, 27th Jan., 1896
Complete Specification Left, 27th Nov., 1896-Accepted, 27th Feb., 1897
PROVISIONAL SPECIFICATION.
Improvements in Processes and Apparatus for Reducing Metals from
their Ores, and for Obtaining Carbides, Acetylene, Cyanogen,
Cyanides, Nitrides, and for Fixing Nitrogen.
I, HUDSON MAXIM, now temporarily residing at The Astor House, in and for the
City of New York, State of New York, United States of America, (Post Office
Box 2488) Chemist, do hereby declare the nature of this invention to be as
follows:-
The present invention relates generally to a process and apparatus for electro-
thermally treating materials, especially the reduction of metals from their oxides,
the production of carbides and the fixation of atmospheric nitrogen, all as hereinafter
explained. And it consists in subjecting the material or materials to be treated or
reduced to the action of a gaseous fluid heating medium deriving its heat,
preferably, from the combined action of the combustion of fuel in oxygen and
electrical heat energy.
In carrying out my invention for the production of calcium carbide, as an
illustration in a general way of the practical application of the improved process
and apparatus, and to the production of carbides in particular, I first charge an
electric furnace or electrical heater with some suitable refractory material and
preferably one not acted upon by the gaseous fluid medium passed therethrough,
which material becoming highly heated presents an extensive heating surface and
sufficiently retards the onward passage of the fluid medium being heated so that
it will be raised to the desired temperature. The material with which the electric
furnace is charged may be blocks of carbon, or particles of carbon such as coke,
charcoal, hard coal, and the like, fire-clay or magnesium or calcium oxide.
When the electrical furnace and its charge has reached the proper temperature, a
gaseous fluid medium is passed therethrough, such fluid having been preferably
previously heated to as bigh a temperature as can be practically reached by the beat.
obtained by the ordinary combustion of a suitable fuel such as carbon or a hydrocarbon
in atmospheric oxygen or by the combustion of hydrogen in oxygen. The gaseous
fluid thus being comparatively highly heated is passed into and through the aforesaid
electrical furnace or superheater, wherein the gaseous fluid is raised to an exceedingly
high temperature. It is thence conducted to a suitable receiver, chamber, or blast
furnace into which is charged calcium oxide and a suitable quantity of carbonaceous
matter or carbon and through which the said highly heated gaseous fluid is passed;
thereby, imparting a portion of its heat to the mixture fof carbon and calcium oxide
which is immediately raised to a very high temperature, at or about the temperature
of the heated fluid medium itself, which rapidly reduces the mixture to a molten mass
or reduces it to calcium carbide; that is to say, the very high temperature secured
in the manner described rapidly causes the carbon to combine with the calcium,
setting free the oxygen from the calcium oxide which combines the carbon present,
producing carbonic oxide and calcium carbide. The blast, furnace containing the
mixture of carbon and calcium oxide is preferably of considerable vertical height, and
is preferably constructed in a manner similar to the ordinary blast furnace; the
carbon and calcium oxide being either intermittently or continuously fed into the top

page_text: of the chamber as required, and the molten calcium carbide drawn or tapped off at
the hottom of the furnace intermittently, or allowed to escape freely and constantly
as fast as formed, or blown off as by an atomizer to form a pulverulent comminuted;
disseminated or flocculent product. As the gaseous fluid heating medium passes
through the blast furnace its temperature is lowered, its heat being imparted to the
mixture of carbon and calcium oxide, the liotter or lower portions of the said mixture
being first subjected to the hotter portions of the gaseous fluid and the cooler or upper
portions of the mixture being subjected to the fluid after it has given out a portion
of its heat to the lower strata or portions of the material in the furnace. The gaseous
fluid may be drawn off from the top of the charging chamber and be thence conducted
to a suitable receiver or gasometer from whence it may be utilized as a fuel or for
illuminating purposes according as desired, should the fluid be an illuminating gas
such as carbonic oxide, hydrogen, and acetylene.
The means for heating the fluid beating medium before it passes through the
electrical superheator may consist of a primary heater the heat of which is produced
by the combustion under pressure and preferably under a forced draft, of a solid,
liquid or gaseons fuel with oxygen or atmospheric air. The fluid means is led from
2:source of supply such as a gasometer or reservoir and forced if needed by a
compressor through a conduit of large surface arranged within the primary heater so
as to be heated in its passage therethrough. Instead of employing a separate primary
heater, the fluid medium may pass through a passage heated by the radiated beat
from the electric superheater. A single structure may embrace the blast furnace,
electric superheater or superheaters (more than one may be employed) and primary
heater; or the blast furnace and primary heater may be separated a distance apart
with the electrical superheater arranged horizontally between them and forming the
conduit for the fluid medium from the heater to the furnace; and in this latter form
the electrical heater may be of rotary form.
When either carbonic oxide or water gas is employed, and which I prefor to
employ, as a fluid heating medium when making calcium carbide, a portion of the
carbonic oxide formed in the reaction is conducted from the above mentioned receiver
or gasometer and forced through the heating apparatus before mentioned and thenco
passed into and through an electric superheater, or zone of electrical beat-energy,
produced in any suitable manner, and thence into and through the blast furnace
containing the materials to be treated, such for instance as calcium oxide and carbon.
When I wish to produce a rich illuminating gas simultaneously with the production
of calcium carbide or other carbide, steam or hydrogen or a hydrocarbon is preferably
employed as the fluid heating medium which in its transit through the electric super-
heater containing carbon and through the carbide forming furnace, containing
preferably an excess of carbou, the oxygen of the steam, when steam is used as the
heating medium, is converted into carbonic oxide and the hydrogen of the steam is
made to combine with a portion of the carbon, through which it, is caused to pass at
a very high temperature, producing acetylene. Such gaseous products of reaction
in this case would consist mainly of carbonic oxide and acetylene, a very rich and
valuable illuminating and heating medium. The pressure necessary for circulating the
steam through the portions of the apparatus may be secured by the pressure of
the steam itself from an ordinary steam boiler, or by other well known means.
When carrying out my invention with a view to tho production of cyanogen as a
portion of the products of the reaction, 1 employ nitrogen for the heating fluid
medium, which at the very high temperatures through which it is made to pass, in
the presence of carbon, causes a partial or more or less mplete conversion of the
nitrogen and carbon into cyanogen. The gaseous products of the reaction are then
preferably passed through a solution of caustic potash or caustic baryta. The
cyanogen reacting with the caustic alkali produces cyanide of potash or barium as the
case may be. The excess of products of the reaction in this case are mainly
carbonic oxide, and may be utilized for heating or illuminating purposes, as for
example, the said gaseous products may be utilized in heating the fluid beating
medium before it enters the electric superbeater.

page_text: When employing the present process and' apparatus for the manufacture of nitrides,
the blast furnace before referred to is charged with the desired metal or other material,
as for example magnesium, or magnesium carbide, or boron. Nitrogen gas or air is
then caused to pass into and through a primary heating apparatus, such as that before
mentioned, thence into and through an electric superheater and thence into and
through the said. blast furnace containing the material or materials desired to be
converted into nitrides.
When it is desired to employ this process and apparatus for the manufacture of
cyanides the said, charging-chamber or blast furnace may be supplied with a suitable
mixture of carbon and a suitable caustic alkali such as caustic potash or caustic
barium, and nitrogen, employed as a heating mediuin, be then passed therethrough
as herein described. At the very high temperature of the nitrogen the carbon
displaces the oxygen in the caustic alkali and nitrogen combines therewith, that is,
with the calcium or barium, as the case may be.
When employed for the reducing of metals from their oros, the same may be
place in the blast furnace or charging chamber with a reducing agent, and a suitable
Buid heating medium passed therethrough and the ores reduced in much the same
manner as they are reduced in an ordinary smelting furnace except that 'a much
higher temperature may be had by this method and much more refractory metals
treated.
When reducing ores or in making calcium carbide, instead of mixing the ores or
the oxide with a reducing agent, I may nse a hydrocarbon heating fluid, which will
itself serve as a reducing agent.
When employing carbonic oxide as a fluid heating medium I prefer to line the
electric furnace or electric superheater and the conduits through which the fluid
heating medium passes to and from the electric superheater or furnace, with carbon
or a carbon compound which will not be acted upon by the carbonic oxide at the high
temperature imparted thereto.
When employing nitrogen or other gas as the fluid heating medium I likewise
construct the said electric furnace wall and conduit walls' of or line them with a
substance unaffected by the respective gases at the high temperatures employed.
It will thus be seen that by means of the improved process and apparatus for
raising the temperature of a fluid heating medium an intensely heated gaseous mediam
is produced capable of treating or reducing the most refractory materials and enabling
the production on a practical scule of substances or compounds heretofore only
obtainable at great expense, in limited quantities and by complicated methods.
The improved process also makes it possible to use so intensely heated fluid medium
that it alone may serve as the reducing agent, so that there need be no combustion
take place in the blast furnace. Gaseous fluids may also be employed which will
not be open to the objections to the use of oxygen as is sometimes the case.
When making calcium carbide I may use ordinary limestone instead of the oxide
of calcium bereinbefore referred to; and when in making an illuminating gas in
connection with the manufacture of the carbide, a sufficient excess of carbon would
be mixed with the limestone not only to reduce it to a carbide but to reduce the
carbonic acid set free from the limestone to carbonic oxide.
.
The electrical rotary furnace herein before referred to may be lined with a material
like calcium carbide unacted upon by carbonic oxide or other suitable neutral gas.
The carbide becoming fused would form within the rotary furnace a molten or fluid
wall which would by centrifugal force be held in position."
Duted this 27th day of Jonname 1806
HASELTINE, LAKE & Co.,
45 Southampton Buildings, W.C., Agents for the Applicant.

page_text: Improvements in Processes and Apparatus for Reducing Metals from
their Ores, and for Obtaining Carbides, Acetylene, Cyanogen;
Cyanides, Nitrides, and for Fixing Nitrogen.
I, HUDSON MAXIM, formerly temporarily residing at The Astor House, in and for
the City of New York, State of New York, United States of America (Post Office
Box 2488) but now residing at Thurlow Lodge, 377 Norwood Road, London, S.E.,
Chemist, do hereby declare the nature of this invention and in what manner the same
is to be performed, to be particularly described and ascertained in and by the following
statement-
The present invention relates generally to a process and apparatus for what I may
term electro-thermally treating materials, and relates especially to the reduction of
metals from their oxides, the production of carbides and the fixation of atmospheric
nitrogen, all as hereinafter explained. And my invention consists mainly in subjecting
the material or materials to be treated or reduced to the action of a gaseous fluid
heating medium deriving its heat from the combined action of the combustion of
fuel in air or oxygen and of electrical heat energy.
According to my invention and for the production of calcium carbide, I employ
an electric furnace or electrical heater charged with some suitable refractory material
which will not be acted upon by the gaseous heating medium passed therethrough.
This material by becoming highly heated, prosents an extensive heating surface to the
gaseous heating medium and sufficiently retards the onward passage of the said heating
medium admitted to the furnace, to ensure its being raised to the desired high
temperature. The material with. which the electric heater is charged may consist of
blocks of carbon, or particles of carbon such as coke, charcoal, hard coal, and the
like, or instead of carbon I may use fire-clay, magnesiuin or calcium oxide.
a
The gaseous fluid heating medium prior to its passage through the electric furnace
is preferably passed through a primary heater to raise it to as high a temperature
as can be practically reached by the heat obtained by the ordinary combustion of
a suitable fuel, such as carbon or a hydrocarbon in atmospheric oxygen, or by the
combustion of hydrogen in oxygen. The gaseous fluid heating medium having thus
been comparatively highly heated, is passed into and through the aforesaid electric
furnace or superheater, wherein it is raised to an exceedingly high temperature. It
is thence conducted to a suitable receiver, chamber or blast furnace which is charged,
with calcium oxide and a suitable quantity of carbonaceous matter or carbon, through
which the said gaseous fluid now in a highly heated condition is passed. The said
gaseous fluid imparts portion of its heat to the mixture of carbon and calcium
oxide, which is immediately raised to a very high temperature, at or about tho
temperature of the gaseous fluid itself, which temperature rapidly reduces the mixture
to a molten mass or reduces it to calcium carbide; that is to say, the very high
temperature thus obtained rapidly causes the carbon to combine with the calcium,
setting free the oxygen from the calcium oxide, which combines with the carbon
present, thereby producing carbonie oxide and calcium carbide. The molten calcium
carbide can be drawn or tapped off at the bottom of the blast furnace intermittently,
or allowed to escape freely and constantly as fast as formed, or be blown off by
an atomizer to form a pulverulent, comminuted, disseminated or flocculent product.
The gaseous fluid may be drawn off from the top of the blast furnace and be thenre
conducted to a suitable receiver or gasometer, from which it may be taken to be
utilized as a fuel, or, if the gaseous fluid be an illuminating gas such as carbonic oxide,
hydrogen, or acetylene, it may be utilized for illuminating purposes.
In some cases I arrange the electrical superheater so that it is capable of rotation.

page_text: into effect I will proceed to describe the same more fully with reference to the
accompanying drawings, in which
Figure 1 is a sectional elevation of the improved apparatus.
Figure 2 is a sectional elevation of certain adjuncts to the said apparatus.
Figure 3 is a horizontal section showing a modified arrangement of the main parts
of the apparatus illustrated in Figure 1.
Figure is a sectional elevation of a modified construction of the apparatus
illustrated in Figure 1.
Figure 5 is an enlarged sectional detail of a portion of the apparatus shown in
Figure 4.
Figure 6 is a sectional elevation of another modified form of the apparatus shewn
in Figure 1.
Like letters of reference indicate similar parts in all the figures.
Referring more particularly to Figure 1, A is the primary heater provided with a
series of conduits or tubes B through which the gaseous fluid heating medium is
passed to receive its preliminary heating prior to entering the electrical superheater.
This superheater consists of two chambers CD through which the preliminary heated
gaseous heating medium passes in order that its temperature may be raised' sufficiently to
render it suitable for effective use in tho blast furnace E. The primary heater has a
fuel feeder A¹ and is also provided with suitable means for producing and heating a
blast therefor. E' is a feeder for the material supplied to the blast furnace; and Fis
a reservoir or gasometer to receive and store the gaseous products coming from the
blast furnace after the gaseous heating medium has acted upon the material in the
said furnace.
The several chambers forming the primary heater, electrical' superheater and blast
furnace are preferably contained by a single closed and gas proof structure S to
prevent undue radiation of heat and enable the operations to be carried on under.
pressure without escape of the gases.
The primary heater A has an ordinary grate a for the combustion of any suitable
form of fuel such as coal or other carbonaceous matter, and such as may be fed thereto
through a feed passage a from the feeder A'. This feeder consists of a vortical
hopper a² communicating with a horizontal conduit a having therein a feed screw a
that is rotated by power applied to a belt pulley a keyed fast on the shaft of the feed
screw. By these means the fuel fed into the conduit a is gradually supplied to tho
grate of the primary heater to replace the fuel thereon as fast as it is consumed.
To prevent the undue escape of the gases under pressure from the heater A in
feeding the fuel thereinto, the hopper a² or other part of the feeder is provided with a
pair of valves a a' of piston form operated by a single stem a. When the lower
valve as is closed, as shewn, a quantity of fuel may be supplied to the space above
the valve, the stem and valves may then be moved downwardly so that the upper
valve a' closes the hopper while the lower valve is moved into the enlarged space
just above the opening to the horizontal conduit and allows the supply of fuel to pass
by gravity into said conduit to be taken by the feed screw.
From the primary heater rises a stack A' the opening from the heater thereto
being governed by a weighted valve h to maintain the desired pressure within the
heater and allow any excess of gaseous pressure to blow off automatically and pass
upward through the stack.
The combustion of the fuel in the primary heater is intensified by the use of a
forced draft or blast which reaches the heater by nozzles i projecting upward from
a blast pipe connected with any source of pressure supply. This blast, however,
is preferably beated by conducting the pressure supply through a pipe which
extends into a coil within the stack A2 and thence leads by a brunch into a
chamber formed in the walls of the furnace structure immediately above and
around the upper portion of the primary heater and a portion of the stack. The blast
pipe communicates with this chamber i, said pipe being controlled by a valve i³.
The conduit B for the gaseous fluid heating medium is closed with respect to the

page_text: interior of the primary heater and is arranged therein so that the gaseous fluid
heating medium shall have a sufficiently long travel to ensure that it shall be raised
to a temperature as high as the combustion of ordinary fuel can impart to it. This
conduit is formed by a number of tubes or tiers of tubes extending horizontally across
the heater from top to bottom thereof, with their ends communicating with closed
alternating passages 6 forined in the walls of the structure around the primary
heater, the wliole forming a circuitous conduit extending from the upper portion of
the heater down toward its grate. The upper or inlet end of the conduit communi-
cates with a gaseous fluid heating medium supply pipe leading from any suitable
source of supply, and the lower or exit end of the conduit communicates with an
interior passage 6 leading the primarily heated gaseous fluid heating medium to the
electrical superheater. Of course other modes of preliminarily heating the, gaseous
fluid heating medium may be adopted.
Instead of using a solid carbonaceous fuel for heating the primary heater A, a
gaseous fuel may be employed. Thus when the gaseous fluid heating medium, fod
through the conduit B, is a combustible fluid such as water gas, a portion or excess
thereof may be burned in the heater A. For this purpose, a pipe (shown in dotted
lines in Figure 1) is led from the feed pipe 61 to the grate or lower portion of the
heater A and terminates in a suitable burner to burn the combustible with a proper
supply of air or oxygen admitted to said heater in any appropriate manner. This
pipe has a valve b7 by which the supply of the combustible can be shut off or other-
wise controlled.
The chambers C, D, forming the electrical superheater, are vertically arranged, and
the passage b communicates with the bottom of the chamber C. The two chambers
communicate at their upper ends by a short passage 63 and the lower end of the
chamber D communicates with a passage & leading directly to the lower portion of
the blast furnace E.
The chamber C is provided with two or more terminals, or electrodes c, c', connected
in circuit with an electric generator c. These electrodes are supported in any
suitable manner, preferably at the bottom and top of the chamber respectively by
insulating plugs securely fastened in place by bolts levers or other suitable means.
These plugs serve also to close the opposite ends of the said chamber; by removing
them, ready access can be had to the interior of the chamber. This chamber Cis
preferably filled with blocks of carbon or other refractory material which under
the beat of the electric current passing between the aforesaid electrodes become very
highly heated and raised to incandescence, thereby providing an extended and intense
heat zone through which the preliminarily heated gaseous fluid is conducted to raise
it to a very high temperature.
The other chamber. D of the electrical super heater has its upper and lower ends
closed by removable plugs d securely fastened in position, and is provided with
numerous terminals, or electrodes d preferably arranged in the form of a spiral
extending from end to end of the chamber and connected, in series or multiple arc,
with an electric generator d. This chamber is preferably filled with some highly
refractory material such as blocks of fire clay D' which, under the heat of the electric
current passing. between the electrodes, become incandescent, thereby providing an
additional large heating surface for the already highly heated gaseous fluid to pass
over, thereby ensuring that its temperature shall be raised to the desired extent to
be capable of performing efficient work in the blast furnace E to which it is then
ready to pass.
The blast furnace E may be of the usual form of such furnaces, the passage b* for
the highly superheated gaseous fluid heating medium ontering near the lower end or
breast thereof. The extreme lower end of the furnace communicates with the
hearth e whereon the fluid material from the furnace can accumulate and be run off
or otherwise disposed of. Instead of this form of hearth the fluid material may be
tapped off in a manner usual in blast furnaces. The upper end of the furnace com-
municates with a pipe e for conducting, to some place of storage, the spent gaseous
fluid heating medium together with such other gases as may be formed by the reaction

page_text: occurring in the furnace. The blast furnace is intermittently or continuously charge 1
with the material or materials to be reduced or otherwise treated, from a hopper e
on the feeder E', which is provided with a feed screw e rotated by power applied to
a belt pulley e on the shaft of the feed screw.
In some instances it may be desirable or necessary to forcibly discharge the fluid
material from the bottom or lower portion of the blast furnace in order to form a
comminuted or flocculent product of the molten or fluid mass. For this purpose the
blast pipe is extended and terminates in a nozzle e adjacent to the discharge
opening of the blast furnace; so that a blust of high pressure and if necessary of
high temperature can be directed against the outward flowing molten mass to
disseminate it and form a product either of considerable porosity or of a flocculent
nature. Where the temperature of this blast is required, to be very high an
interior passage e (shewn by dotted lines in Figure 1) may be formed in the walls
of the structure, such passage leading from the passage downward, alongside of
the superheater chamber C, to the nozzle c. In such case the blast pipe is.
preferably not extended to the said nozzle, but is employed solely to conduct the
blast to the primary heater A.
In Figure 2 there are shown continuations of the pipes, e, and ; the blast..
pipe leading from a suitable blower or compressor G; the fluid medium supply
pipe leading from a blower or compressor H.; and the pipe e being connected'
to an exhaust apparatus I which in turn forces the gases through a pipe into the.
receiver or gasometer F for storage or further use. Instead of passing the gases
directly to the gasometer they may pass through'a cooler, separator or scrubber, or
other receptaele J (shown in dotted lines) and thence to the gasometer. The gaseous.
fluid heating medium supplied by the compressor H may take its supply from the-
gasometer F by a pipe h, or from some other source of supply or place of storage.
In Figure 3. a slightly different arrangement of the several chambers in the
apparatus, is shown, such arrangement requiring somewhat less space than the
structure shown in Figure 1. The primary heater A. with its conduit B is brought
closer to the blast furnace E, while the electrical superheating, chambers C, D, are-
separated laterally from one another; otherwise the construction is similar to that.
previously described. The entire structure may be rendered gas tight by any suitable
means, as by an iron or steel shell S¹; and when employing carbonic oxide as the
gaseous fluid heating medium the conduits through which such fluid passos, and the-
electric furnace, will be lined with carbon or a carbon compound S which will not.
be acted upon by the carbonic oxide at its high temperature. The blast furnace E
may likewise be lined with a highly refractory material S which in some cases may
be formed of a carbonaceous material. And when using such gas as nitrogen or
other gases that when highly heated, are likely to affect the wills of the conduits,
or chambers, there will be employed a lining that will remain unaffected by such
guses.
In the modified construction shown in Figures 4 and 5 the superlieater is in the
form of a horizontal structure C2 interposed between the heater A and the blast.
furnace E and constitutes as before a continuation of the conduit B. This horizontal
electric superheater is preferably a rotary one and for this purpose is mounted to
rotate on rollers k, and receives its motion from any suitable source of power through
a belt . The construction of the superheater and the manner of mounting.its.
ends are shown in Figure 5, wherein is the metallic outer shell of the superheater,.
having enlarged ends fitting upon an extension 3 which extends into a chamber 4
communicating with the passage leading to the blast furnace. The outer shell
and its extension are electrically insulated from each other by an interposed
packing . This shell is furnished with a lining of some refractory material.
such as a carbide capable of melting under the heat of the superheater and thus.
forming under the action of centrifugal force, due to the rotation of the superheater,
an interior fluid wall or protective lining therefor. The interior space of the heater
may be filled with blocks of carbon C which become heated to incandescence formu
an extensive beating surface with which the gaseous fluid heating medium comes

page_text: into contact on its way to the blast furnace. The joint between the end of the
superheater and the chamber is made gas tight by a packing annulus ke, the
larger end of which is exposed to the pressure of the highly heated gases on their
way to the blast furnace. The said annulus and the extension are held in a non-
rotating block supported by an annular bracket secured to the stationary
walls of the chamber. The electrodes or terminals in this caso consist of a tubular
or perforated block e located at each end of the superheator and connected in
circuit with an electric generator c³ as before.
In the further modified construction shown in Figure 6, the electrical super-
heater and blast furnace E, are intimately combined in a single structure S. In
this case the gaseous fluid heating medium instead of passing through a primary
heater of the kind shewn in Figure 1, is led through a spirally arranged passage. A³
surrounding the superheater and heated by the heat of radiation therefrom. The
gaseous fluid heating medium is led to the bottom of the passage A3 and by passing.
upward therein enters the superheater at its upper end, and by passing downward
in the superbeater reaches the blast furnace by the passage *.
When, as I prefer, either carbonic oxide or water gas is. employed to serve as the
gaseous fluid heating medium, a portion of the carbonic oxide formed in the reaction
is conducted froin the above mentioned receiver or gasometer F and forced through
the primary heater and through the electric superheater, or zone of electrical heat
energy, and thence into and through the blast furnace containing the materials to
be treated, such for instance as calcium oxide and carbon.
When I wish to produce a rich illuminating gas simultaneously with the production
of calcium carbide or other carbide, steam or hydrogen or a hydrocarbon is preferably
employed as the gaseous fluid heating medium. The oxygen of the steam, when
steam is used, is converted into carbonic oxide and the hydrogen of the steam is
made to combine with a portion of the carbon through which it is caused to pass
at a very high temperature thereby producing acetylene. Such gaseous products of
reaction in this case would consist inainly of carbonic oxide and acetylone, a very
rich and valuable illuminating and heating medium. The pressure necessary for
circulating the steam through the apparatus may be secured by the pressure of the
steam itself from an ordinary steam boiler, or by other well known means.
When applying my invention to the production of cyanogen as a portion of the
products of the reaction, I employ nitrogen for the gaseous fluid heating medium,
which at the very high temperatures to which it is subjected in the presence of carbon
in the blast furnace, causes a partial or more or less complete conversion of the
nitrogen and carbon into cyanogen. The gaseous products of the reaction are then
preferably passed by a pipe e to the receiver J containing a solution of caustic potash
or caustic barium. The cyanogen reacting with the caustic alkali produces cyanide
of potash or barium as the case may be. The excess of products of the reaction
in this case is mainly cartonic oxide, and may be utilized for heating or
illuminating purposes; for example, the said gaseous products may be utilized in
heating the gaseous fluid heating medium before it enters the electrical
superlieater.
When employing my process and apparatus for the manufacture of nitrides, the
blast furnace E is charged with the desired metal or other material, as for
example magnesium, or magnesium carbide, or boron, and nitrogen gas or air as
the feating medium is then caused, to pass through the apparatus whereby the
materials in the blast furnace are convert d' into nitrides.
When it is desired to employ this process and apparatus for the manufacture of
cyanides the blast furnace E may be supplied with a mixture of carbon and a suitable
caustic alkali such as caustic potash or caustic barium, through which mixture
nitrogen, employed as a heating medium, is then passed as herein described. At the
very high teinperature of the nitrogen the carbon displaces the oxygen in the caustic
alkali and nitrogen combines therewith, that is, with the calcium or barium, as the
case may be.
When my process and apparatus.are employed for reducing metals from their ores,

page_text: the ores are placed in the blast furnace with a reducing agent, and a suitable gaseous
fluid heating medium passed therethrough as above explained; the ores are then
reduced in much the same manner as they are reduced in an ordinary smelting
furnace except that a much higher temperature is obtained by this method and ores of
a much more refractory nature can be treated thereby..
When reducing ores or making calcium carbide, instead of mixing the ores or the
calcium oxide with a reducing agent, I may use a hydrocarbon heating fluid, which
will itself serve as a reducing agent.
It will thus be seen that by means of my invention I can produce a gaseous heating
medium which is so intensely heated that it is capable of treating or reducing the
most refractory materials and of enabling the production on a practical scale of
substances or compounds heretofore only obtainable at great expense, in limited
quantities and by complicated methods.
The improved process also makes it possible to use a gaseous heating medium
so intensely heated that it alone may serve as the reducing agent, so that no
combustion need take place in the blast furnace. I may also einploy gaseous
fluids which will not be open to the objections that sometimes arise, to the use of
oxygen.
When making calcium carbide I may use ordinary limestone instead of the oxide
of calcium hereinbefore referred to, and when making an illuminating gas in connection
with the manufacture of the carbide, a sufficient excess of carbon would be mixed
with the limestone, not only to reduce it to a carbide but to reduce the carbonic acid,
set free from the limestone, to carbonic oxide.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the saine is, to be performed, I declare that what I
claim is :-
1. In a process for reducing metals from their oros, or for obtaining carbides,
acetylene, cyanogen, cyanides or nitrides, or for fixing nitrogen, the employment of
a gaseous fluid heating medium which is, or is not, according to the kind of substances
or materials treated, of a nature to chemically react on the said substances or materials
and which is heated to the requisite high temperature by electricity substantially as
described.
2. The manner of producing a highly heated gaseous heating medium by subjecting
such medium to the action of heat due to electricity either alone or in addition to the
action of heat of combustion, substantially as described and for the purposes
specified.
3. The manner of heating a gaseous fluid heating medium for the purposes specified.
by passing it over carbon or other heating surfaces which have no affinity for the
heating medium, and which have been heated to the requisite temperature by
electricity substantially as described.
4. The utilization of carbonic oxide as a heating medium substantially as described
and for the purposes specified.
5. The production of a carbide by means of carbonic oxide which is used as a
gaseous heating medium substantially as described.
6. The production of calcium carbide by passing a highly heated hydrocarbon
through a calcium compound substantially as described.
7. The production of acetylene by passing highly heated hydrogen or a gaseous
fluid containing hydrogen through carbon substantially as described.
8. The fixation of nitrogen by subjecting it to electrical heat energy and then
combining with it another body substantially as described.
9. The production of cyanogen by subjecting carbon to a current of heated nitrogen
substantially as described.
10. The production of a cyanide by subjecting an alkali to a current of nitrogen
heated substantially as described.
11. The production of cyanogen simultaneously with calcium carbide by passing
heated nitrogen through a calcium compound in the presence of carbon and then
в

page_text: separating the cyanogen from the carbonic oxide or other products of the reaction
substantially as described.
12. The production of an illuminating gas by superheating steam substantially'as
described and then subjecting carbonaceous matter to the action of the steam so
superheated.
13. The production of carbide in a comminuted or flocculent condition by forming
the carbide into a more or less molten condition and then subjecting it to the blast of
a highly heated gaseous medium substantially as described.
14. Apparatus for use in the various processes herein before set forth, consisting of
a furnace, a conduit for conducting a gaseous fluid heating medium to the furnace,
means for preliminarily heating the gaseous fluid passing through said conduit and an
electrical superheating chamber or electrical superheating chambers in communication
with the said conduit, substantially as described.
15. The arrangement of the aforesaid electrical superheating chamber in a rotary
form substantially as described and for the purpose specified.
16. A rotary electrical furnace having a molten or flaid wall or lining maintained
in position by the action of contrifugal force, for the purposes specified...
17. The apparatus substantially as described with reference to one or other of
the arrangements illustrated in the accompanying drawings and for the purposes
specified.
D1:: 0741 1.
1000
Haseltine, Lake & Co.,
HUDSON MAXIM.
45 Southampton Buildings, London, W.C., Agents for the Applicant.