IMPROVEMENTS IN METALLURGICAL, FURNACES
Year: 1876

page_text: LETTERS PATENT to William Morgan-Brown, of the Firm of Brandon and
Morgan-Brown, Engineers and Patent Agents, of 38, Southampton Buildings,
London, and 13, Rue Gaillon, Paris, for the Invention of "IMPROVEMENTS IN
METALLURGICAL, FURNACES." A communication from abroad by Elliot Savage,
of West Meriden, County of New Haven, Connecticut, United States of
America.
Sealed the 14th July 1876, and dated the 24th January 1876.
PROVISIONAL SPECIFICATION left by the said William Morgan-Brown at
the Office of the Commissioners of Patents on the 24th January 1876.
WILLIAM MORGAN-BROWN, of the Firm of Brandon and Morgan-Brown, Engineers
and Patent Agents, of 38, Southampton Buildings, London, and 13, Rue Gaillon,
Paris. IMPROVEMENTS IN METALLURGICAL FURNACES."
This Invention of improvements in metallurgical furnaces has for its objects,
first, to prevent the oxidation of the metal in the smelting chamber when brought
to a high temperature by supplying said chamber with the reducing gases at the
requisite degree of heat to smelt the metal without producing complete combustion
in the chamber; and, second, to prevent the waste of fuel by supplying the reducing
gases after leaving the smelting chamber with a fresh supply of oxygen to produce
complete combustion, and utilize the heat thus produced to heat the reducing gases
to the proper temperature before entering the smelting chamber.
It is well known that in the ordinary process of combustion oxygen and carbon
can be made to combine in two definite proportions forming carbonic oxide (CO) or
carbonic acid (CO.), carbonic oxide being formed when carbon is burned in a limited
supply of oxygen, carbonic acid being the result of the perfect combustion of
carbon, carbonic oxide containing one atom of carbon and one atom of oxygen,
carbonic acid being composed of one atom of carbon and two atoms of oxygen.
When one pound of carbon is combined in the process of combustion with one and
one-third pound of oxygen the total amount of heat developed is 4400 British
thermal units, the product being two and two-thirds pounds of carbonic oxide,
which can be combined by combustion with one and one-third pound of oxygen,
and by so doing develope heat amounting to 10,100 thermal units.
When one
pound of carbon is combined in the same manner with two and two-thirds pounds
of oxygen, the amount of beat developed is 14,500 thermal units, and the product

page_text: •
of combustion is three and two-thirds pounds of carbonic acid (CO,). The burning
of carbon, as it takes place in the combustion chambers of ordinary furnaces, is
always complete at first, provided the layer of coal from which the carbon is
obtained is not so thick and the supply of air so small, but that oxygen in sufficient
quantity can get direct access to all the solid carbon, that is to say, one pound of
carbon combines with two and two-thirds pounds of oxygen, and makes, as stated
above, three and two-thirds pounds of carbonic acid, and thus carbon, which is solid
immediately before the combustion, passes during the combustion into the gaseous
state forming with the oxygen carbonic acid gas, and producing 14,500 thermal units
per pound of carbon consumed, and under these conditions the process terminates ;
but when part. of the solid carbon in the furnace is not supplied directly with
oxygen, being first heated and then dissolved into the gaseous state by the hot
carbonic acid gas, which has already been formed in it, the product is carbonic
oxide gas, three and two-thirds pounds of carbonic acid gas being capable of dis-
solving one pound of carbon, and thus making four and two-thirds pounds of carbonic
oxide gas.
The volatilizing of this second pound of carbon causes a loss of heat
amounting to 5,700 thermal units, which being taken from the 14,500 thermal units
produced by the perfect combustion of one pound of carbon, there remains 8,800
thermal units. Should the process stop here the waste of fuel is very great, but
if the four and two-thirds pounds of carbonic oxide gas is mixed with a sufficient
quantity of fresh air of proper temperature it will burn with a blue flame, and
the product will be seven and one-third pounds of carbonic acid gas, the amount of
heat developed in the process amounting to 20,200 thermal units. Adding to this
the 8,800 thermal units, above we have 29,000 thermal units as the result of the
perfect combustion of two pounds of carbon.
It is well known to metellurgists that carbonic oxide in its action upon metals
and metallic oxides is a reducing gas, and that metals are not readily oxidized, even
when exposed to it at a high temperature. It is also known that when metals
which have an affinity for oxygen are exposed to the action of carbonic acid
gas at a high temperature, they are rapidly oxidized, and thus burned up and
wasted.
In the furnaces in common use for manufacturing wrought iron the atmosphere
of the heating chamber is usually kept in such a state, as to prevent the oxidation
of the iron while it is being hented; this is accomplished by supplying the com-
bustion chamber of the furnace with a large amount of carbon, which of necessity
must be burnt in a limited supply of air which results in a large waste
of fuel.
The method by which this waste is prevented will be understood by the following
description of this improved metallurgical furnace :-The parts of the furnace
consist of a first combustion chamber or fire-box and ash-pit, and an uptake shaft,
a flue by which the air is conducted to the ash-pit, a flue for conducting air to a
second combustion chamber, a flue in which the reducing gases are heated on their
passage through to a smelting chamber. The coal is fed from a box with inclined
plane, down which the fuel passes into a coking chainber. There is a flue to convey
the gases from the smelting chamber to the second combustion chamber which
surrounds the fluc carrying the reducing gases, and in which flue gaining a fresh
supply of oxygen they are completely consumed. Fire being kindled in the first
combustion chamber, the box being filled with coal, air is forced in by the ash-pit
Alue up through the fire-bars of the fire-box. Complete combustion is produced
immediately above the grate bars.
The result of this complete combustion (CO₂) passing up through the incandescent
fuel receives from the fuel being coked on dead plate of coking chamber another
portion of carbon forming carbonic oxide. This reducing gas passing through flue
into smelting chamber, and there into the second combustion chamber, receiving a
fresh supply of oxygen as stated previously, the perfect combustion of the fuel is
accomplished. The heat thus generated is communicated to the walls of the
second combustion chamber and the flue, the gases then passing out to the uptake,

page_text: When a sufficiently high temperature has been attained for the purpose desired
the combustion can be retarded by regulating the supply of air through the air
passages conducting air to the ash-pit or to the second combustion chamber, thus a
great saving of fuel is accomplished, and a strictly reducing gas introduced into
and maintained in the smelting chamber, while the oxidizing flame is confined
entirely to the second combustion chamber.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Morgan-Brown in the Great Seal Patent Office on the 17th
July 1876.
WILLIAM MORGAN-BROWN, of the Firm of Brandon and Morgan-Brown, Engineers
and Patent Agents, of 38, Southampton Buildings, London, and 13, Rue Gaillon,
Paris. "IMPROVEMENTS IN METALLURGICAL FURNACES." A communication to me
from abroad by Elliot Savage, of West Meriden, County of New Haven, Con-
necticut, United States of America.
The objects of this Invention are, first, to prevent the oxidation of the metal in
the smelting chamber when brought to a high temperature by supplying said
chamber with the reducing gases at the requisite degree of heat to smelt the metal
without producing complete combustion in the chamber; and, second, to prevent
the waste of fuel by supplying the reducing gases after leaving the smelting
chamber with a fresh supply of oxygen to produce complete combustion, and utilize
the heat thus produced to heat the reducing gases to the proper temperature before
entering the smelting chamber.
It is well known that in the ordinary process of combustion oxygen and carbon
can be made to combine in two definite proportions forming carbonic oxide (CO) or
carbonic acid (CO2), carbonic oxide being formed when carbon is burned in a limited
supply of oxygen, carbonic acid being the result of the perfect combustion of
carbon, carbonic oxide containing one atom of carbon and one atom of oxygen,
carbonic acid being composed of one atom of carbon and two atoms of oxygen.
When one pound of carbon is combined in the process of combustion with one and
one-third pound of oxygen the total amount of heat developed is four thousand four
hundred British thermal units, the product being two and two-thirds pounds of
carbonic oxide, which can be combined by combustion with one and one-third
pound of oxygen, and by so doing develope heat amounting to ten thousand
and one hundred thermal units. When one pound of carbon is combined in the
same manner with two and two-thirds pounds of oxygen the amount of heat
devoloped is fourteen thousand and five hundred thermal units, and the product of
combustion is three and two-thirds pounds of carbonic acid (CO). The burning of
carbon, as it takes place in the combustion chambers of ordinary furnaces, is always
complete at first, provided the layer of coal from which the carbon is obtained is
not so thick and the supply of air so small, but that oxygen in sufficient quantity
can get direct access to all the solid carbon, that is to say, one pound of carbon
combines with two and two-thirds pounds of oxygen, and makes, as stated above,
three and two-thirds pounds of carbonic acid, and thus carbon, which is solid
immediately before the combustion, passes during the combustion into the gaseous
state, formning with the oxygen carbonic acid gas, and producing fourteen thousand
and five hundred thermal units per pound of carbon consumed, and under these
conditions the process terminates; but when part of the solid carbon in the furnace
is not supplied directly with oxygen, being first heated and then dissolved into the
gaseous state by the hot carbonic acid gas, which has already been formed in it,
the product is carbonic oxide gas, three and two-thirds pounds of carbonic acid gas
being capable of dissolving one pound of carbon, and thus making four and two-
thirds pounds of carbonic oxide gas. The volatilizing of this second pound of
carbon causes a loss of heat amounting to five thousand and seven hundred thermal

page_text: units, which being taken from the fourteen thousand and five hundred thermal
units produced by the perfect combustion of one pound of carbon, there remain
eight thousand and eight hundred thermal units. Should the process stop hero the
waste of fuel is very great, but if the four and two-thirds pounds of carbonic oxide
gas is mixed with a sufficient quantity of fresh air of proper temperature it will
burn with a blue flame, and the product will be seven and one-third pounds of
carbonic acid gas, the amount of heat developed in the process amounting to twenty
thousand and two hundred thermal units. Adding to this the eight thousand and
eight hundred thermal units above we have twenty-nine thousand thermal units as
the result of the perfect combustion of two pounds of carbon.
It is well known to metallurgists that carbonic oxide in its action upon metals
and metallic oxides is a reducing gas, and that metals are not readily oxidized, even
when exposed to it at a high temperature. It is also known that when metals
which have an affinity for oxygen are exposed to the action of carbonic acid
gas at a high temperature they are rapidly oxidized, and thus burned up and
wasted.
In the furnaces in common use for manufacturing wrought iron the atmosphere
of the heating chamber is usually kept in such a state as to prevent the oxidation
of the iron while it is being heated; this is accomplished by supplying the com-
bustion chamber of the furnace with a large amount of carbon, which of necessity
must be burned in a limited supply of air, which results in a large waste
of fuel.
The method by which this waste is prevented will be understood by the following
description of this improved metallurgical furnace :-In the several Figures of the
Drawings A represents the first combustion chamber of fire-box; B, the ash-pit;
C, the uptake; D, the flue through which air is conducted to the ash-pit; E, the
flue for conducting air to the second combustion chamber; F, the flue in which tho
reducing gases are heated on their passage through it to the smelting chamber G;
I represents the coking chamber; H, the fuel chamber or coal box having an
inclined plate, down which the fuel passes into the coking chamber I; J, a fluo for
conducting the gases from the smelting chamber G to the second combustion
chamber L; K, the door of the smelting chamber; L represents the second com-
bustion chamber (surrounding the flue F), in which the gases after leaving the
smelting chamber G passing through flue J, and receiving a fresh supply of oxygen
through the passage leading from flue E, are completely consumed...
The mode of operation is as follows:-Fire being kindled in first combustion
chamber and box H being filled with coal, air is forced through flue D into ash-
pit B, and up through the grate bars. Complete combustion is produced immediately
above the grate bars.
The result of this completo combustion (CO₂) passing up through the incandescent
fuel receives from the fuel being coked on dead plate of coking chamber I another
portion of carbon forming carbonic oxide; this reducing gas passing the flue F
into smelting chamber G, and from there into chamber L through flue J receiving
after leaving chamber G and flue J a fresh supply of air through the passage
leading from flue E, the perfect combustion of the fuel is accomplished. The heat
thus generated by this second combustion is communicated to the walls of
chamber L and the flue F, the gases then passing out into the air through the
uptake C.
When a sufficiently high temperature has been attained for the purpose desired
the combustion can be retarded by regulating the supply of air through the air
passages E and D, and thus a great saving of fuel accomplished, and a strictly
reducing gas introduced into and maintained in the smelting chamber, while the
oxidizing flame is confined entirely to the chamber L.
For the purpose of completely preventing any air entering the flue J the passage
from said fluc made smaller than the entering passage to it, thus causing and
maintaining an outward pressure in the chamber.
Having now described and particularly set forth the nature of the said Invention,

page_text: and the manner of carrying the same into effect, I would have it understood that I
claim,
First. The combination, substantially as herein-before set forth, of the flue for
conducting the heated gases from the first combustion chamber to the smelting
chamber and the second combustion chamber for heating said flue.
Second. The combination, substantially as herein-before set forth, of the flue for
conducting the heated gases from the first combustion chamber, the second com-
bustion chamber for heating said flue, and the smelting chamber intervening said
flue and second combustion chamber.
Third. The combination, substantially as herein-before set forth, of the flue for
conducting the heated gases from the first combustion chamber into the smelting
chamber and the second combustion chamber for heating said flue with a flue for
admitting air into said second combustion chamber.
In witness whereof, I, the said William Morgan-Brown, have hereunto set my
hand and seal, this Seventeenth day of July, in the year of our Lord One
thousand eight hundred and seventy-six.
WILLIAM MORGAN-BROWN. (L.S.)