IMPROVEMENTS IN FURNACES FOR TREATING METALS AND ORES
Year: 1878

page_text: LETTERS PATENT to Herbert John Haddan, of the Firm of Herbert and Com-
pany, Patent Agents, of 67, Strand, in the City of Westminster, Civil Engineer,
for the Invention of "IMPROVEMENTS IN FURNACES FOR TREATING METALS
AND ORES." A communication from abroad by Samuel Thomas Owens and
William McNair, both of Allegheny, State of Pennsylvania, United States of
America.
Sealed the 10th May 1878, and dated the 14th March 1878.
PROVISIONAL SPECIFICATION left by the said Herbert John Haddan at the
Office of the Commissioners of Patents on the 14th March 1878.
E
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Patent Agents,
of 67, Strand, in the City of Westminster, Civil Engineer. IMPROVEMENTS IN
FURNACES FOR TREATING METALS AND ORES." A communication from abroad by
Samuel Thomas Owens and William McNair, both of Allegheny, State of Pennsyl-
vania, United States of America.
The Invention consists in placing a shelf or hearth at back and above the fire-
box for the reception of the fuel when it is first fed into the furnace, and which hearth
is heated from underneath by the waste products of combustion, so as to decompose
the coal and generate gas and carbonic oxide, whereby the whole of the coal is used
as a fuel, and a greater amount of heat obtained from a smaller or the same quantity
of fuel, and a great saving effected.
The Invention further consists in the arrangement and combination of parts that
will be more fully described herein-after.
When the coal contains but a small portion of gas, and it is desired to convert a
larger portion of it into carbonic oxide before being fed upon the grate, suitable air
holes are made through the front or side of the walls above the hearth, so as to
admit any quantity of air that may be desired.

page_text: As the fuel is consumed, and the carbonic oxide formed rises up over the bridge,
it receives another equivalent of air, and is then converted into flame in a converting
chamber, where the perfect combustion takes place.
One great advantage in thus decomposing the fuel is, that all the sulphur in the
coal is driven off in a gaseous space, and this sulphurous acid mingling with the air
over the bridge is at once driven off, before it can attack the metal or ore in the
chamber. By thus protecting the metal from the action of the sulphur, a finer and
better grade of iron, etc., is produced in every way, both in tensile strength and
fibre, and for making steel and fine sheet iron.
The hearth of the chamber may be made to conform to the use to which the
chamber is applied.
The waste products of combustion pass down the flue forward through two
flues, one on each side of the central air flue, up under the hearth, and then up the
stack.
The air passes through an inlet forward through the flue towards the front
of the furnace, across into a second flue back towards the rear end, down
through another flue and towards the front end of the furnace through a central
flue.
From the front end of the flue the heated air. rises through the flues up into
the chamber, from which chamber it escapes through the small perforations over
the top of the grate bars and reducing chamber.
It is intended that after the air once passes through the inlet, it shall move
constantly forward through one flue after another until it reaches the chamber,
which chamber and flues are all heated to such a degree as to raise the air to a very
high temperature.
By suitable arrangement of the flues, the air is constantly increased in tempera-
ture until it escapes into the fire, instead of being allowed to cool in places, as in
many other furnaces.
The perforations through which the air escapes from the chamber are to be made
quite small, so as to break the air up into minute particles, and thus prevent the
air from descending upon the fire in volumes. When the air is thus broken up, it
mingles thoroughly and completely with the products of combustion, and this causes
a more perfect combustion to take place than would otherwise occur.
In working a furnace with the above improvements when an oxidizing or reducing
flame is needed, the air is allowed to pass through the flues to mingle with the
products of combustion, and thereby cause an excess of oxygen in the reducing
chamber.
When it is desired to use a deoxidizing flame, all air is shut off from the flues, and
then there will be an excess of carbon in the products of combustion in the reducing
chamber, and the iron will be carbonized thereby.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Herbert John Haddan in the Great Seal Patent Office on the
6th September 1878. -
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Patent Agents,
of 67, Strand, in the City of Westminster, Civil Engineer.
"IMPROVEMENTS IN
FURNACES FOR TREATING METALS AND ORES." A communication from abroad by
Samuel Thomas Owens and William MoNair, both of Allegheny, State of Pennsyl-
vania, United States of America.
The Invention consists-in placing a shelf or hearth at back and above the fire-
box for the reception of fuel when it is first fed into the furnace, and which
hearth is heated from underneath by the waste products of combustion, so as to be
decompose the coal and generate gas and carbonic oxide, whereby the whole of the
coal is used as fuel, and a greater amount of heat obtained from a smaller or
saine quantity of fuel, and a greater saving effected.
The Invention further consists in the arrangement and combination of parts that
will be more fully described herein-after.
In the accompanying Drawing the letter a represents the fire-box; b, the bridge;
and c, the reducing chamber arranged and constructed in the usual manner.
...In-the-front end of the fire-box, above and at back of the bars, is the hearth d
upon which the coal is thrown so as to be heated and converted into gas or carbonic.
oxide, before it is fed forward upon the grate.
Where the coal contains but a small portion of gas, and it is desired to con-
vert a large portion of it into carbonic oxide before being fed upon the grate,
suitable air holes are made through the front or side of the walls above the hearth,
so as to admit any quantity of air that may be desired.
The hearth being heated from underneath by the waste products of combustion,
as shown, the fuel is decomposed so as to throw off its volatile matter, and then as
the solid carbon that is left behind is fed forward upon the grate, it is converted
into carbonic oxide.
As the fuel is consumed, and the carbonic oxide formed rises up over the bridge,
it receives another equivalent of air and is then converted into flame in a con-
verting chamber where the proper combustion takes place.
One great advantage in thus decomposing the fuel, is that all of the sulphur
in the coal is driven off in a gaseous space, and this sulphurous acid mingling
with the air over the bridge, is at once driven off before it can attack the metal or
ore in the chamber c. By thus protecting the metal from the action of the
sulphur a finer and better grade of iron, etc., is produced in every way, both in
tensile strength and fibre, and for making steel and fine sheet iron.
The hearth of the chamber c may be made to conform to the use to which the
chamber is applied.
The waste products of combustion pass down the flue y forward, two flues x, one
on each side of the central air flue m, up under the hearth, and then up the stack.
The air passes through the inlet i forward through the flue j towards the front of
the furnace, across into the second flue n, back towards the rear end, down through
the flue o and towards the front end of the furnace through the central flue m.
From the front end of the flue m the heated air rises through the flues q up into
the chamber p, from which chamber it escapes through the small perforations over
the top of the grate bars and reducing chamber.
P,
It is intended that after the air once passes through the inlet i, it shall move
constantly forward through one flue after another, until it reaches the chamber
which chamber and flues are all heated to such a degree as to raise the air to a very
igh temperature.
By suitable arrangement of the flues here shown, the air is constantly increased
n temperature until its escape into the fire, instead of being allowed to cool in
laces, as in many other furnaces.

page_text: The perforations through which the air escapes from the chamber p are made
quite small so as to break the air up into minute particles, and thus prevent the
air from descending upon the fire in volumes. When the air is thus broken up, it
aningles thoroughly and completely with the products of combustion, and this causes
a more perfect combustion to take place than would otherwise occur.
In working a furnace with the above improvements when an oxidizing or reducing
flame is needed, the, air is allowed to pass through the flues to mingle with the
products of combustion, and thereby cause an excess of oxygen in reducing
chamber.
When it is desired to use a deoxidizing flame, all air is shut off from the flues,
and then there will be an excess of carbon in the products of combustion in the
reducing chamber, and the iron will be carbonized thereby.
Having thus described the Invention, I claim,-
1st. In combination with a heating and puddling furnace, the hearth d placed
in a line with the waste products of combustion, and upon which the fuel is first
thrown, so as to be heated from underneath by said products as they escape up
the stack, substantially as shown and described.
2nd. The combination of the flues j, n, o, m, arranged so as to be heated by the
products of combustion, and to continuously raise the temperature of the air passing
through them, substantially as set forth.
3rd. The combination of the flues j, n, o, m, and chamber p, substantially as
specified.
In witness whereof, I, the said Herbert John Haddan, have hereunto set my
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