IMPROVEMENTS IN CONSUMING GASEOUS PRODUCTS OF COMBUSTION PRODUCED IN FURNACES AND FIRE-GRATES GENERALLY, AND IN THE MEANS OR PROVISIONAL SPECIFICATION
Year: 1874

page_text: LETTERS PATENT to John Stirling and Thomas Peacock, both of
Coatbridge, in the County of Lanark, North Britain, for the In-
vention of "IMPROVEMENTS IN CONSUMING GASEOUS PRODUCTS OF COMBUSTION
PRODUCED IN FURNACES AND FIRE-GRATES GENERALLY, AND IN THE MEANS OR
PROVISIONAL SPECIFICATION left by the said John Stirling and
Thomas Peacock at the Office of the Commissioners of Patents,
with their Petition, on the 6th October 1874.
We, JOHN STIRLING and THOMAS PEACOCK, both of Coatbridge, in
the County of Lanark, North Britain, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN CONSUMING GASEOUS PRODUCTS OF
COMBUSTION PRODUCED IN FURNACES AND FIRE-GRATES GENERALLY, AND IN THE
MEANS OR APPARATUS EMPLOYED THEREFOR," to be as follows, that is to
say:-
This Invention which relates to improvements in consuming smoke or
gaseous products of combustion generated or produced in furnaces or
fire-grates employed in raising steam in steam boilers, in the manufacture
of iron and steel, and for other purposes for which fire heat is required

page_text: consists in discharging on the gases either whilst in the furnace wherein
the fuel is consumed, or whilst the gases are passing over the fire
bridge a current of highly heated atmospheric air, which mixing with
the said gases consumes them.
In employing this Invention in conjunction with reverberatory,
puddling, reheating, or other similar furnaces used in the manufacture
of iron, the air is heated by being conducted through a pipe or pipes
extending throughout the flue or flues of one or more steam boilers, at
one end of which the said pipe or pipes are open to the atmosphere or
connected to any suitable air forcing apparatus, whilst at the opposite
end of the boiler or boilers the pipe or pipes communicate with a flue or
with flues extending along the roof or top of the chamber wherein the
conversion of the iron is effected. In passing through the flue or flues
the air is additionally or superheated by radiation from the said chamber.
Dampers or valves are provided to regulate the passage of air through
the pipe or pipes herein-before referred to. From the flue or flues the
heated air passes through ports into the interior or to the fire bridge of
the furnace or fire-grate wherein the fuel is placed, where meeting with
the gases it inflames them, the flame being conducted through the
operating chamber of the puddling or other furnace. After passing
through the said chamber the heated waste products of combustion pass
through the flue or flues of the boiler or boilers in which the air pipe or
pipes are situate, as herein-before described, whereby the air is heated
and steam is generated in the said boiler or boilers.
Under another arrangement of this Invention steam may be raised in
steam boilers by placing the furnace or fire-grate at the end thereof
opposite to that at which the air enters into the heating pipe or pipes,
and discharging the heated air on the gases arising from the fuel in the
said furnace before the said gases are allowed to pass into or through
the boiler flues.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Stirling and Thomas Peacock in the Great
Seal Patent Office on the 6th April 1875.

page_text: Drawings at the end of the boiler C, but it may be placed at the side of
or apart from the boiler. Heated air is supplied to the puddling furnace
through the pipe or passage G which passes through the boiler flue H,
and is hung or supported therein partly by the brickwork and partly by
stirrups I attached to the interior of the flue H. One end of the pipe G
is open to the atmosphere, or it may be placed in communication with
an air forcing apparatus, and at that end a valve or damper J is placed
by which the supply of air passing through the pipe or passage G is
regulated. At the end opposite from the valve or damper J the pipe G
is placed in communication with a covered passage or flue K which
passes along the roof or crown of the puddling chamber L, and at the
end.of which another flue or chamber M is situated in communication
with any number of ports N situated above the fire-bridge O, and
through which the heated air passes into the furnace. The smoke and
5 gases arising from the fuel in the furnace or fire-grate B become imme-
diately ignited upon coming into contact with the currents of hot air
issuing from the ports N, and the flame thus generated passes into the
puddling chamber L free from smoke and other gaseous impurities.
From the chamber L the flame and heated waste products of com-
bustion pass through the boiler flue H, heating in their passage the
current of air in the pipe G, and thereafter having circulated round the
boiler Othrough the flues D and E escape to the atmosphere by the
chimney stalk F. The current of air in the pipe G is further heated
during its passage through the flue K by the heat radiated from the roof
5 or crown of the puddling chamber L.
•
Figure 4 is a cross vertical section of the boiler O shewing more par-
ticularly the position of the pipe G in the boiler flue H.
It is to be understood that although we have described our said In-
vention in conjunction with one puddling furnace and one single
) flued boiler it may be applied to any greater number of puddling,
reverberatory, reheating, and other similar furnaces, and in conjunction
with one or more single or double flued boilers, or to furnaces without
boilers attached, and to boilers of classes other than those shewn in the
annexed Drawings, such for example as are of the locomotive or marine
5 type; also instead of employing a single air pipe or passage, as herein-
before described, two or any greater number may be employed, while the
passage or flue K (Figure 3) may be made the full breadth of the
furnace crown so as to utilize all the heat radiated therefrom,

page_text: Figures 5 and 6 are illustrations of our Invention as applied to ordinary
flued boilers. Figure 5 represents the hot air pipe A as introduced
through the furnace door. The heat evolved from the fuel in the
furnace B is imparted to the air passing through the pipe A, so that
when it is discharged upon the smoke and gases as they pass over the 5
fire-bridge O the gases are ignited, in which state they pass along the
flue D, but we prefer to introduce the air pipe from the other end of
the boiler, as shewn at Figure 6, where the air pipe A is brought from
the back of the boiler, and the hot air discharged either into the furnace
or above the fire-bridge. By the latter arrangement a greater length of 1
heating surface of the air pipe is exposed and to a more intense heat.
In lieu however of suspending the air pipe above the fire-bridge it may
also be led through the fire-bridge and the hot air blown into or above
the fuel on the fire-bars.
"
Having now described and particularly ascertained the nature of our 1
said Invention, and the system, mode, or manner in or under which the
same is or may be used or practically carried into effect, we would
observe in conclusion that what we consider to be novel and original and
therefore claim as the Invention secured to us by the herein-before in
part recited Letters Patent is, the arrangements whereby air is heated 2
by passing through pipes or flues exposed to the waste heat of com-
bustion and discharged in the heated state into a furnace for uniting
with and burning the gaseous products of combustion in furnaces
generally, as herein-before described.
In witness whereof, I, the said John Stirling, on behalf of myself 2
and the said Thomas Peacock, have hereunto set my hand and
seal, this Second day of April One thousand eight hundred and
seventy-five.