IMPROVED METHODS OR PROCESSES OF, AND APPARATUS FOR, TREATING ORES TO PURIFY AND PREPARE THE SAME FOR SMELTING
Year: 1883

page_text: LETTERS PATENT to William Robert Lake, of the firm of Haseltine, Lake &
"
Co, Patent Agents, Southampton Buildings, London for an Invention of
"IMPROVED METHODS OR PROCESSES OF, AND APPARATUS FOR, TREATING ORES
TO PURIFY AND PREPARE THE SAME FOR SMELTING communicated to him
from abroad by Cummings Cherry, Senior, of Chicago, Illinois, United States
of America, Chemist and Geologist
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 18th December 1883.
WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake, and Co, Patent Agents,
Southampton Buildings, London "IMPROVED METHODS OR PROCESSES OF, AND
APPARATUS FOR, TREATING ORES TO PURIFY AND PREPARE THE SAME FOR SMELTING
"
[A communication to him from abroad by Cummings Cherry, Senior, of Chicago,
Illinois, United States of America, Chemist and Geologist]
This invention relates to a process of, and apparatus for, treating ores, and has
for one of its objects to purify iron, gold, silver, copper and lead ores and prepare
them for smelting by freeing or expelling their impurities such as phosphorus,
sulphur, antimony, arsenic and other metalloids and the oxygen from the naturally
formed metallic oxides which may be combined with them chemically or otherwise
in their natural condition; and all other impurities susceptible of being removed
in a gaseous form.
Another object is to overcome difficulties heretofore existing in the preliminary
treatment of ores by providing suitable apparatus whereby an uniform temperature
is maintained about the retort so that as a result a more uniform product is
obtained.
The said invention comprises the improved process hereinafter described and
improvements in apparatus for carrying the said process into practice, the said
improvements consisting partly in providing the lower portion of the retort
employed, with a perforated pipe or bottom, or both, through which air, steam,
or gas may be admitted to the ores undergoing treatment for the purpose of

page_text: creating an upward current of the gases evolved from the ores so that the same
may be carried off at the top of the retort and conducted through pipes to a
condenser; partly in forming around the retort, and within the same, vertical
flues having fire brick arranged therein so as to leave spaces or interstices for the
passage of the heat and gases whereby the passage of such heat and gases is
retarded and an uniform temperature is created and maintained on the outer
surfaces of the retort for the treatment of the ores within the retort where they
are excluded from the influence of atmospheric air and other gases until desired to
admit the same; and partly in the construction and combination of parts herein-
after particularly described.
In carrying the said invention into practice the ores to be treated are broken up
or crushed into particles of suitable size, or may be pulverized. In case the ores
are in a refractory condition with silex and other impurities of like nature, a
mixture of chloride of lime, chloride of soda, and pulverized carbon, or either of
them, as the condition may require, is intimately mixed with the crushed ore. The
ores, or the ores and mixture, are then placed in a closed retort, muffle, or oven of
suitable form and construction to allow their being heated by an external fire.
The retort is air-tight with an outlet or escape pipe at the top which is arranged
with valves to be opened or closed at pleasure and also to maintain any pressure
required within the retort. The retort is also provided with a gas-supply pipe and
gas chamber at the bottom. The said pipe is arranged with valves for the
introduction, under perfect control, of gases, steam, and air.
When the retort is charged the valve in the supply pipe is regulated to prevent
the admission of atmospheric air, but permitting the gases and vapors within to
escape. The retort is then subjected to heat until the temperature of the ores has
reached 800 to 1000 degrees Fahrenheit, but preferably 500 to 700 degrees
Fahrenheit, or thereabouts. This condition is maintained until the water of
crystallization and of constitution of the ores and acid formations and all fugitive
gases and volatile substances thus expellable are vaporized and passed off through
the escape pipe, which has been regulated for that purpose during the treatment
to allow the freest escape of the gases compatible with complete exclusion of
atmospheric air.
This treatment constitutes the first part or step in this process and the time
occupied or required is about two hours. Under the said treatment the cohesion
of the ores is partially destroyed by evaporization of the water of crystallization
and all the acid combinations are broken up by the evaporation of their water of
constitution. The oxides are partially disintegrated by the expelling of the oxygen,
and the fugitive gases and volatile substances are vaporized and passed off and the
ores partially deoxidized. The ores and their remaining impurities are thus left
in a porous and spongy condition and are thus prepared or conditioned to act with
greater chemical energy and effect in forming the new combinations produced by
the second step in this process.
Where the fluxes and carbon have been used the
refractory condition has been broken up and the disintegration of the ores greatly
assisted.
In the second step the valve of the escape pipe is regulated to maintain a
pressure within the retort of not less than thirty pounds, and wet or superheated
steam is then introduced through the supply pipe and gas-chamber slowly and
continuously until it has attained a pressure of not less than thirty pounds,
preferably fifty to sixty pounds, fully permeating the mass. The temperature of
the ores in the retort is maintained at 700 to 1000 degrees Fahrenheit, during
which wet or superheated steam is forced under the said pressure in sufficient
volume to fully pass through the ores or mass and out through the escape pipe.
This treatment is continued until chemical combinations have been formed with
the phosphorus, sulphur, antimony, arsenic and metalloids or other impurities
existing in combination with the ores and have passed off or been forced through
the escape pipe in the form of sulphuretted hydrogen, phosphuretted hydrogen,
phosphine, antimonial and arsenical vapors & &; this condition can readily be

page_text: ascertained by the odour of the escaping vapors through the escape pipe. During
this operation the oxygen of the steam has combined with the metal in the ores
and a portion of the escaping metalloids, forming with phosphorus the red oxide
of phosphorous or amorphous phosphorus which remains in the retort. The ores
are now substantially free from sulphur and the other metalloids which may have
been combined with them the remaining impurities being in combination with
oxygen.
In the third step the same temperature is maintained but the steam is then
turned off, and superheated air is introduced through the supply pipe and gas
chamber until it has attained a pressure within the retort of not less than ten
pounds, preferably twenty to twenty five pounds. At this stage the valve of the
escape pipe is so regulated as to maintain the said pressure, and a current of super-
heated air is forced through the ores under such pressure in sufficient volume to
permeate the whole mass, and pass through and out at the escape pipe. This
treatment is continued until all the remaining phosphorus, sulphur, and other
metalloids are expelled and ores susceptible of reoxidation have become thoroughly
re-oxidized.uniformly throughout their whole mass, the time required being about
one hour.
The ore thus treated is ready for smelting and may be fed directly into the
smelting furnace in its heated condition.
If salts and silica have existed in excess in the ores to be treated, chlorine gas
is introduced under pressure in the same manner and under the same pressure as
the superheated air, and such treatment continued until the ores have become
thoroughly chloridized.
The treatment should be continuous in the order named excluding all contact
with atmospheric air except such as is introduced in the manner stated because
the chemical changes are thus under better control of the operator and take place
while the gases and elements are in their normal condition, thereby securing the
greatest chemical energy.
Ores treated in this manner will be found free from phosphorus, sulphur,
antimony arsenic and other metalloids, and such as are susceptible of reoxidation
will have become thoroughly and uniformly.reoxidized to protoxides and peroxides,
all producing, when smelted, an uniform quality of superior metal.
In constructing apparatus for carrying out the foregoing described process
I provide suitable masonry upon which the said apparatus is supported and by
which it is or may be surrounded. An interior chamber is formed in the masonry
in which is placed the retort which is of cast iron or other suitable material and
preferably tapers slightly from the top to the bottom. The said retort is provided
with an extension through the top of the masonry which extension is provided
with a cover, and from this extension an escape pipe provided with a safety valve
at its upper part and a controlling check valve at its lower part extends down to a
condensing chamber in which the said pipe is coiled and then passes out through
the same.
The retort has an interior flue which connects at its upper end by lateral flues
with the chamber which encircles the retort. The top of the said interior flue
above the lateral flues is provided with a cap, and the interior of the flue is filled
with fire bricks set one upon another so as to leave spaces or interstices of from
two to four inches between them. The interior flue is provided with a lower
extension which passes down through a gas chamber and connects with a lateral
flue which leads to a second chamber. The lower extension is filled with fire-brick
the same as the upper part of the flue and the whole of the bricks within the flue
are supported on a perforated bridge wall.
The exterior of the retort is protected by a fire-clay or "ganister" covering, and
a flue surrounding the retort is filled with fire-brick placed therein the same as in
the interior flue and supported on a perforated arched bottom.
The retort has a perforated bottom the front portion of which is adapted to be
moved by a rod extending through the masonry, the opening through which it

page_text: passes being made steam and air tight. Within the retort just above its perforated
bottom, there is placed a pipe having perforations so as to direct currents of air,
gases, or steam into the bottom of the retort. This pipe has one end connected
with a branch of the main from which it receives its supply of air gas or steam and
the other end opens outside the furnace without having any connection but is
provided with a valve. The main is supplied with air, gas, or steam through a
pipe which leads from the superheating troughs and pipes located in a third
chamber. The pipes and troughs in this chamber are surrounded by fire-brick
built up the same as in the interior and exterior flues and resting upon the arch
above the second chamber, which arch has flues therein. The air or steam for the
said superheaters is received from a steam-generator or air-compressor through a
main which supplies the several troughs and through branches each of which is
provided with a valve so that the steam or air may be cut off from any one or
more of the said troughs and the main is provided with a valve by means of
which all of said branches may be cut off from the supply.
The third chamber communicates with an escape flue through a series of openings
and with the exterior flue through a flue which is provided with a damper.
The furnace is provided with a grate which is somewhat lower than the top of
the gas chamber but the furnace extends up above the gas chamber and is provided
with doors for the introduction of the fuel, and communicates with the second
chamber through a flue which has a damper operated in a similar manner to all
the other dampers by rods which extend outside of the masonry. The second
chamber is also provided with a grate so that if the heat received from an outside
blast furnace through a pipe is not sufficient, a fire may be made in the chamber
for more heat. The chamber is also provided with doors for the introduction of
the fuel and the withdrawal of the ashes from the pit.
The gas-chamber is also provided with a grate which inclines downwardly to a
chute which is provided with a door, and below the grate there is a door to the
chamber.
A pipe leads from a branch of the main into the gas-chamber and is used to
introduce steam, hot air, and other gases to the chamber, under pressure.
In this plant there may be as many retorts as desired, with their appropriate
connections.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Robert Lake in the Patent Office on the 17th June
1884.
WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake, and Co Patent Agents.
Southampton Buildings. London, "IMPROVED METHODS OR PROCESSES OF, AND
APPARATUS FOB, TREATING ORES TO PURIFY AND PREPARE THE SAME FOR SMELTING."
A communication to me from abroad by Cummings Cherry Senior, of Chicago,
Illinois, United States of America, Chemist and Geologist.
This invention relates to a process of and apparatus for treating ores and has for
one of its objects to purify iron, gold, silver, copper and lead ores and prepare them
for smelting by freeing or expelling their impurities such as phosphorus, sulphur,
antimony, arsenic and other metalloids, and the oxygen from the naturally formed
metallic oxides which may be combined with them chemically or otherwise, in
their natural condition; and all other impurities susceptible of being removed in a
gaseous form.
Another object is to overcome difficulties heretofore existing in the preliminary
treatment of ores, by providing suitable apparatus whereby an uniform temperature
is maintained about the retort so that as a result a more uniform product is
obtained.
The said invention comprises the improved process hereinafter described and
improvements in apparatus for carrying the said process into practise the said
improvements consisting partly in providing the lower portion of the retort
employed with a perforated pipe or bottom, or both, through which air, steam, or
gas may be admitted to the ores undergoing treatment, for the purpose of creating
an upward current of the gases evolved from the ores so that the same may be
carried off at the top of the retort and conducted through pipes to a condenser. It
also partly consists in forming around the retort and within the same, vertical flues
having fire brick arranged therein so as to leave spaces or interstices for the
passage of the heat and gases, whereby the passage of such heat and gases is
retarded and an uniform temperature is created and maintained on the outer
surfaces of the retort for the treatment of the ores within the retort where they are
excluded from the influence of atmospheric air and other gases until desired to
admit the same; and partly in the construction and combination of parts hereinafter
particularly described and specifically defined by the claims.
In carrying the said invention into practice the ores to be treated are broken
up or crushed into particles of suitable size, or may be pulverized. In case the
ores are in a refractory condition, with silex and other impurities of like nature,
a mixture of chloride of lime, chloride of soda, and pulverized carbon, or either of
them, as the condition may require, is intimately mixed with the crushed
The ores, or the ores and mixture, are then placed in a closed retort, muffle,
or oven of suitable form and construction to allow their being heated by an
external fire.
ore.
The retort is air tight with an outlet or escape pipe at the top, which is arranged
with valves to be opened or closed at pleasure and also to maintain any pressure
required within the retort. The retort is also provided with a gas supply pipe
and gas chamber at the bottom. The said pipe is arranged with valves for the
introduction under perfect control of gases, steam and air.
When the retort is charged the valve in the supply pipe is regulated to prevent
the admission of atmospheric air, but permitting the gases and vapors within to
escape. The retort is then subjected to heat until the temperature of the ores

page_text: has reached 800 to 1000 degrees Fahrenheit, but preferably 500 or 700 degrees
Fahrenheit or thereabouts. This condition is maintained until the water of
crystallization and of constitution of the ores and acid formations, and all fugitive
gases and volatile substances thus expellable are vaporized and passed off through
the escape pipe, which has been regulated for that purpose during the treatment
to allow the freest escape of the gases compatible with complete exclusion of
atmospheric air.
This treatment constitutes the first part or step in this process and the time
occupied or required is about two hours. Under the said treatment the cohesion
of the ores is partially destroyed by evaporization of the water of crystallization,
and all the acid combinations are broken up by the evaporation of their water of
constitution. The oxides are partially disintegrated by the expelling of the
oxygen, and the fugitive gases and volatile substances are vaporized and passed
off and the ores partially deoxidized. The ores and their remaining impurities are
thus left in a porous and spongy condition and are thus prepared or conditioned
to act with greater chemical energy and effect in forming the new combinations
produced by the second step in this process. Where the fluxes and carbon have
been used, the refractory condition has been broken up and the disintegration of
the ores greatly assisted.
In the second step the valve of the escape pipe is regulated to maintain a
pressure within the retort, of not less than thirty pounds and wet or superheated
steam is then introduced through the supply pipe and gas chamber slowly and
continuously until it has attained a pressure of not less than thirty pounds,
preferably fifty to sixty pounds, fully permeating the mass. The temperature of
the ores in the retort is maintained at 700 to 1000 degrees Fahrenheit, during
which wet or superheated steam is forced under said pressure in sufficient volume
to fully pass through the ores or mass and out through the escape pipe. This
treatment is continued until chemical combinations have been formed with the
phosphorous, sulphur, antimony, arsenic and metalloids or other impurities existing
in combination with the ores and have passed off or been passed through the
escape pipe in the form of sulphuretted hydrogen, phosphuretted bydrogen,
phosphine, antimonial and arsenical vapors, &°, &; This condition can readily
be ascertained by the odour of the escaping vapors through the escape pipe.
During this operation the oxygen of the steam has combined with the metal in the
ores and a portion of the escaping metalloids, forming with phosphorus the red
oxide of phosphorus or amorphous phosphorus which remains in the retort. The
ores are now substantially free from sulphur and the other metalloids which may
have been combined with them, the remaining impurities being in combination
with oxygen
In the third step the same temperature as before is maintained, but the steam is
turned off and superheated air is introduced through the supply pipe and gas
chamber until it has attained a pressure within the retort of not less than ten
pounds, preferably twenty to twenty-five pounds. At this stage the valve of the
escape pipe is so regulated as to maintain the said pressure, and a current of
superheated air is forced through the ores under such pressure in sufficient volume
to permeate the whole mass, and pass through and out at the escape pipe. This
treatment is continued until all the remaining phosphorus, sulphur and other
metalloids are expelled, and the ores susceptible of reoxidation have become
thoroughly re-oxidized uniformly throughout their whole mass, the time required
being about one hour.
The ore thus treated is ready for smelting and may be fed directly into the
smelting furnace in its heated condition
If salts and silica have existed in excess in the ores to be treated, chlorine gas
is introduced under pressure in the same manner and under the same pressure as
the superheated air and such treatment contained until the ores have become
thoroughly chloridized.
The treatment should be continuous in the order named, excluding all contact

page_text: with atmospheric air except such as is introduced in the manner stated, because
the chemical changes are thus under better control of the operator and take place
while the gases and elements are in their nascent condition, thereby securing the
greatest chemical energy.
Ores treated in this manner, will be found to be free from phosphorus, sulphur,
antimony, arsenic and other metalloids, and such as are susceptible of reoxidation
will have become thoroughly and uniformly reoxidized to protoxides and peroxides,
all producing when smelted an uniform quality of superior metal.
I do not claim broadly the roasting or treatment of ores by heat in closed retorts
for the purpose of purification, except as in connection with the process described.
nor do I claim herein the roasting or treatment of ores by steam in closed retorts,
excluding the atmospheric air, except as in connection with the process described,
and except as under pressure of not less than thirty pounds.
The treatment of ores by superheated steam is not new. it has been applied in
close retorts to heated and melted ore. But I am not aware that it has been.
applied so as to maintain a pressure within the retort Prior to this invention
ores have been subjected to the action of heated air, the air being introduced into
the closed receptacles under pressure without external heat applied to the receptacle
containing it. In such treatment the ores were not previously treated and the
purpose was for desulphurizing them. In my process the ores have a preliminary
treatment which frees them from sulphur. The treatement by superheated air then
produces a different result viz, expelling the remaining phosphorus and reoxidizing
ores capable of reoxidation. Another essential difference is that under my treatment
or process a current of superheated air under pressure is forced through the ores
heated by external fire from 700 to 1000 degrees Fahrenheit forcing a chemical
action not otherwise attainable.
Suitable apparatus for carrying out the process hereinbefore described is,
illustrated in the accompanying drawing, in which
Figure 1 is a central vertical sectional elevation through the furnace
Figure 2 is a plan view showing one of the furnaces in section on the line x x
Figure 1.
A indicates the masonry upon which the said apparatus is supported and by
which it is or may be surrounded.
An interior chamber B is formed in the masonry in which is placed the retort C
of cast iron or other suitable material and preferably slightly tapering from the
top to the bottom. The said retort is provided with an extension D, through the
top of the masonry which extension is provided with a cover F, and from this
extension an escape pipe G, provided with a safety valve at its upper part and a
controlling check valve at its lower part extends down to a condensing chamber H,
in which the said pipe is coiled, and then passes out through the same.
The retort has an interior flue J, which connects at its upper end by lateral
flues K, with the chamber B encircling the retort. The top of the flue J, above
the lateral flues, is provided with a cap M, and the interior of the flue is filled with
fire brick N, set one upon another so as to leave spaces or interstices of from two
to four inches between them. The flue J is provided with a lower extension J',:
which passes down through a gas chamber O, and connects with a lateral flue P
leading to a chamber Q. The lower extension J' is filled with fire-brick, the same
as the upper part of the flue and the whole of the bricks within the flue are
supported on the perforated bridge wall a.
The exterior of the retort is protected by a fire-clay or "ganister" covering I,
and a flue R, surrounding the retort, is filled with fire brick U, placed therein the
same as in the flue J, and supported on a perforated arched bottoin c to the flue.
The retort has a perforated bottom S the front portion of which is adapted to be
moved by a rod d extending through the masonry, the opening through which it
passes being made steam and air tight. Within the retort just above its perforated
bottom there is placed a pipe T having perforations so as to direct currents of air,.
gases or steam into the bottom of the retort. This pipe has one end connected

page_text: with a branch of the main U', from which it receives its supply of air, gas or
steam, and the other end opens outside the furnace without having any connection
but provided with a valve. The main is supplied with air, gas or steam through
a pipe f, which leads from the super-heating troughs V, and pipes V₁, located in the
chamber W. The pipes and troughs in this chamber are surrounded by fire
bricks N built up the same as in the flues J and R, and resting upon the arch x
above the chamber Q, which arch has flues g therein. The air or steam for the said
superheaters is received from a steam generator or air compressor (not shown)
through a main Y, which supplies the several troughs through branches h, each of
which is provided with a valve so that the steam or air may be cut off from any
one or more of said troughs; and the main is provided with a valve i, by means of
which all of said branches may be cut off from the supply.
The chamber W communicates with the escape flue Z, through a series of
openings, and with the flue R, through a flue k, which is provided with a
damper l'.
The furnace B¹ is provided with a grate m, which is somewhat lower than the
top of the gas chamber, but the furnace extends up above the gas chamber and is
provided with doors n for the introduction of the fuel and communicates with
chamber through a flue o, which has a damper p operated in a similar manner
like the other dampers by rods which extend outside of the masonry.
The
chamber is also provided with a grate q, so that if the heat received from an
outside blast furnace through a pipe r, is not sufficient, a fire may be made in the
chamber for more heat. The chamber is also provided with doors for the introduc-
tion of the fuel and the withdrawal of the ashes from the pit.
The gas chamber is provided with a grates which inclines downwardly to the
chute t, which is provided with a door u, and below the grate there is a door v, to
the chamber.
A pipe w leads from a branch of the main U, into the gas chamber O, and is
used to introduce steam, hot air and other gases to the chamber under pressure.
In this plant there may be as many retorts, as desired, with their appropriate
connections although in the drawing I have illustrated only two with their
connections. In operation the retort is filled through the extension D with the
ore to be treated, after which the extension is closed by the cap or cover F
which is luted as usual in such cases. The ore is now subjected to heat passing
through the chamber around the retort and through the central flue, the heat being
received from the furnace B¹, and if necessary also from the chamber Q through
the flue o. The heat passes upward through the chamber B, its passage being
impeded by the bricks set up therein, and then it passes through the lateral flues K,
into the flue J, and then down through the same between the bricks set up therein
into the flue P, at the bottom thereof, and then into the chamber Q, from whence
it may pass upward through flues g, into the chamber W, and there aid in super-
heating the troughs and pipes, its passage through the said chamber being impeded
by the bricks set up therein, so that the full capacity of the heat will be utilized
before being allowed to escape. When the temperature within the retort has been
raised from say 700° to 1000 Fabrenheit, steam is admitted to the retort through
the perforated pipe T, so as to maintain the required pressure within the retort
and permeate the mass, and pass upward through the ore therein until the phos-
phorus, sulphur, antimony, arsenic and other metalloids have formed chemical
union with the hydrogen and oxygen of the steam and have passed through the
escape pipe G, after which the steam is shut off and the hot air or gases admitted
through the same pipe. If desired the hot air or gases or steam may be admitted
through the pipe w. into the gas chamber O, instead of passing it through the
perforated pipe in the retort, or at the same time therewith, the air, gases or steam
then passing upward through the perforated bottom S, into the retort and causing
an upward current so as to overcome the vacuum in the gas chamber and thereby
prevent a downward current through the retort from being formed. The steam
and gases or air are introduced into the chamber under pressure sufficient to.

page_text: permeate the entire mass of ore and maintain the required pressure in the retorts,
and the matters expelled from the ores after collecting in the extension D, pass
therefrom through pipe G, into the condenser H from whence, the condensed
products are delivered into any suitable receptacle, not shown.
The length of time required for treating different charges of ore will vary as
the ores vary and when the ores are discharged they are prepared for introduc-
tion into the smelting furnace and may be fed directly into it in their heated
condition.
After the ore has been sufficiently treated the sliding portion of the perforated
bottom S, is drawn out so as to let the ore fall onto the grate 8, so much thereof as
is small enough passing through the grate into the lower part of the chamber from
whence it is withdrawn through door v, while what is not small enough is with-
drawn through the door of the chute t. When necessary air can be passed into the
pipe T, for the purpose of clearing the pipe from any residuum that may have
settled thereon, the air or a greater portion thereof passing through the pipe and
out therefrom through the other end into the open air, the valve y therein being
opened to allow the escape of the air. Whenever desirable the heating medium or
a portion thereof instead of being allowed to pass into the flue J, may be directed
into the chamber W, through the flue k. Cocks, valves or dampers are provided
for the several pipes as shown in the drawing
By forming the central flue within the retort so that the heating medium may
pass through it as well as through the chamber surrounding the retort a more
uniform heating of the ore is obtained; and by providing the flue and chambers
with the bricks set up with spaces or interstices between them the heating medium
is impeded in its passage through the chambers so that the heat is more fully
utilized before being allowed to escape; and by providing the fire clay or ganister
covering to the retort the sides thereof are protected from the destroying influences
of the intense heat as it passes upward into the chamber from the combustion
chambers
Having thus fully described the said invention as communicated to me by my
foreign correspondent and the manner of performing the same I wish it understood
that I claim
First The process herein described of purifying ores previous to smelting,
consisting in heating the ores or the ores and fluxes in closed retorts, muffles or
ovens, then subjecting the charge thus treated to the action of steam under a
pressure of not less than thirty pounds, and finally subjecting the mass to the action
of superheated air for the purpose of oxidizing to peroxides, in the manner,
substantially as described.
Second The process of desulphurizing ores, the same consisting in heating the
ores to about 700 to 1000 degrees Fahrenheit in closed retorts, muffles or ovens by
external fire and subjecting them to the action of superheated steam under a
pressure within the retort of not less than thirty pounds, in the manner
substantially as specified
Third The process of reoxidizing ores and eliminating phosphorus therefrom, the
same consisting in subjecting the ores at a temperature of about 700 to 1000
degrees Fahrenheit in closed retorts, muffles or ovens heated by external fire, to the
action of superheated air under a pressure within the retort of not less than ten
pounds, in the manner substantially as specified.
Fourth The process of purifying ores previous to smelting, consisting in heating
the ores or the ores and fluxes in closed retorts, muffles or ovens by external fire to
about 500 to 700 degrees Fahrenheit, then subjecting the charge thus treated at a
temperature of 700 to 1000 degrees Fahrenheit, to the action of steam under a
pressure within the retort of not less than thirty pounds, and finally by subjecting
the charge thus treated at a temperature of 700 to 1000 degrees Fahrenheit to the
action of superheated air under a pressure of not less than ten pounds, in the
manner substantially as specified
Fifth. The combination of the closed retort, the heating chambers around the

page_text: same, and the heating flues within the retort communicating with the said chambers,
substantially as described.
Sixth. The combination of the closed retort, the heating chamber around the
same, the heating flue within the retort communicating with the said chamber and
the filling of the chamber and retort having interstices for the passage of the
heating medium, substantially as described.
Seventh. The combination of the closed retort, the gas chamber below the same,
the chamber around the retort, the vertical flue within the retort communicating
with the chamber around the retort and extending into the gas chamber, and the
lateral flue connecting the lower end of the vertical flue with a heating medium
chamber, substantially as described
Eighth The combination of the closed retort, the gas chamber below the same,
the chamber around the retort, the vertical flue within the retort communicating
with the chamber around the retort and extending into the gas chamber, the
lateral flue communicating with the lower end of the vertical flue, the heating
medium chamber connecting with the lateral flue and the chamber containing the
superheaters in combination with the heating medium chamber, substantially as
described
Ninth. The superheating troughs and pipes, in combination with the chamber
containing the filling provided with interstices for the passage of the heating
medium and surrounding the pipe, substantially as described.
Tenth. The combination of the closed retort, the protecting covering thereto, the
chamber surrounding the same, and the flue within the retort communicating with
the chamber around the retort, substantially as described.
Eleventh. The combination of the closed retort, the perforated pipe in the lower
portion thereof, and means for supplying steam, hot air or other gases thereto,
substantially as described.
Twelfth. The combination of the closed retort, the perforated pipe in the lower
portion thereof, the perforated bottom to the retort, the gas chamber below the
retort, the pipe leading into the gas chamber, and means for supplying steam, hot
air and other gases to the perforated pipe within the retort and the pipe opening
into the gas chamber, substantially as described.
Thirteenth. The combination of the closed retort provided with a perforated
bottom, the gas chamber below the retort, the perforated pipe in the lower portion
of the retort, the pipe leading into the gas chamber, the main connecting by
branches with the pipe leading into the gas chamber and the said perforated pipe,
and means for supplying steam, hot air or other gases to the said main,
substantially as described.
Fourteenth. The combination with the closed retort, of the perforated pipe in
the lower portion thereof having both ends extending outside thereof, and
means for supplying air to one end of said pipe and a valve to control its escape at
the other end, substantially as described.
In witness whereof I the said William Robert Lake have hereunto set my hand
and seal this fourth day of June in the year of Our Lord One thousand eight
hundred and eighty four.