Improvements relating to the Generation of Heat by the Combustion of Fuel, and to Apparatus therefor.
Year: 1893

page_text: Date of Application, 6th June, 1893-Accepted, 29th July, 1893
COMPLETE SPECIFICATION.
Improvements relating to the Generation of Heat by the Combustion
of Fuel, and to Apparatus therefor.
We, WILLIAM LUTHER TETER, Inventor, of 214 North Twelfth Street,
Philadelphia, in the County of Philadelphia, State of Pennsylvania, United States
of America, and HENRY LAMARTINE WEBSTER, Commercial Traveller, of 52
Cayuga Street, Seneca Falls, County of Seneca, and State of New York, United
States of America, 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:-
Our invention relates to the generation of heat by the combustion of fuel, and
consists in the new method employed, and in certain novel features in the
construction and arrangement of the furnace or apparatus specially adapted for
carrying out this new method.
The object of the invention is to produce increased heating effects from the
combustion of fuel with economy in the quantity of fuel consumed.
In carrying out our invention we employ ordinary fuel such as coal, and burn
therewith a fuel gas generated by the combustion of the fuel itself and introduced
from below the body of incandescent fuel, by which it has been previously generated,
in such a way as to become intimately mixed therewith and consumed, producing
also a perfect combustion of the coal or solid fuel.
The gas employed is composed of a mixture of hydrocarbon and steam which is
first superheated by the products of combustion of the coal or other fuel so as to be
transformed into a gaseous or partly gaseous condition. While this mixture is being
thus transformed into a gaseous state it is kept from direct contact with the
burning fuel so as not to be consumed thereby. This gas or partly gaseous mixture
is then introduced from immediately below the body of burning fuel and over
substantially the entire area thereof so as to become intimately mixed therewith
throughout its body, and passes up into the burning fuel where it is consumed.
Such ungasified elements as may remain with the mixture when it is introduced
from below the incandescent body in passing up through the same, become by
contact with the hot fuel transformed into a gaseous state and are burned above
the body of the fuel.
This method may be most advantageously employed for the generation of steam
in a boiler. In connection with the oil and steam, superheated air may also be
employed in the formation of the gas.
We shall now refer to the drawings and describe in connection therewith our
improved apparatus designed for carrying out our method of generating heat by
the combustion of fuel, as well as the method itself.
In these drawings:
Fig. 1 is a side elevation with part in vertical section of a furnace and steam
boiler adapted for carrying out our method applied to the generation of steam;
Fig. 2 is a plan view of the burners;
Fig. 3 is a longitudinal vertical sectional view of a portion of a furnace
embodying our invention and illustrating a modification of the construction of some
of the parts; and
Fig. 4 is a sectional plan view of the same on the line x-x of Fig. 3.
We shall first refer particularly to the construction shown in Figs. 1 and 2.
A is the combustion chamber of the furnace. B is the fire grate upon which the
coal or other solid fuel is supported.
C is a boiler.
Disa amoke outlet or staale
the hurnar lanated under the cerato B and

page_text: consisting of a series of perforated pipes connected with a main F. The perforated
pipes of the burner E extend over substantially the entire area of the grate B, so as
to supply gas equally throughout the extent of the body of fuel thereon.
G is a superheating and mixing chamber in which the gas is generated. This
superheating chamber is located above the grate and preferably in the rear thereof
so as to be in the path of the products of combustion therefrom and to leave the grate
unobstructed for the reception of the fuel.
The chamber G is connected with the burner through a pipe f
I is a pipe leading from an injector J to the chamber G by which the mixture of
steam and oil is conducted to the chamber G.
K is a steam pipe for conveying steam to the injector J. This pipe K
connects with the exhaust pipe I, through the valved pipe M. It may also connect
with the boiler C to supply live steam to the injector J through a valved steam
pipe K' as shown.
N is a blower for forcing air into the pipe O which connects with the steam
pipe K preferably below the point of junction of the pipe K and exhaust pipe M.
The pipe O may pass through the smoke outlet or stack adjacent to the outer
end of the boiler in the form of a coil whereby the air therein may be heated before
it is mixed with the steam in the pipe K.
o is a valve in the pipe O.
P is an oil reservoir, the upper portion of which may be connected with the
injector J through a valved pipe Q.
The steam pipe K₁ is connected with the bottom of the reservoir P to supply
steam thereto to force out the oil from the reservoir into the pipe Q. The
water of condensation from the steam in the bottom of the reservoir holds the
oil at the top.
p is an outlet for the water of condensation.
R is a supply tank for supplying oil to the reservoir P.
S is the hot water heater of the engine exhaust pipe. L'; and s is the usual back
pressure valve.
•
We shall now describe the operation of this apparatus in carrying out our new
method.
The coal or other fuel is placed upon the grate B and is ignited in the usual
manner. Steam, which may be either exhaust steam from the exhaust pipe L', or
live steam from the boiler, or a mixture of both, enters the injector and draws
with it a quantity of oil from the reservoir P.
This mixture of steam and oil enters the chamber G and therein becomes
thoroughly mixed and transformed into a gaseous condition by the heat of the
chamber from the combustion of the fuel on the grate. The oil is thus transformed
into volatile hydrocarbon and reacting with the decomposed steam forms hydrogen,
carbon monoxide and other combustible gases and these gases pass through the
pipe to the burners E, and emerging therefrom, below the body of incandescent
fuel upon the grate, are evenly distributed throughout the area thereof and are
burned with the fuel producing a more complete combustion thereof and great
heating effects.
In practice a portion of the steam is usually not decomposed, and these
undecomposed portions of the steam emerging from the pipes E pass up through the
body of the incandescent fuel and by contact therewith are converted into hydro-
carbon and carbon monoxide and together with some of the hydrocarbon gases pass
through the body of the fuel and are consumed in the space immediately above
the same.
If desired the oil and steam may be introduced separately into the chamber G.
Hot air may also be introduced with the steam and oil. The supply of fuel upon
the grate B should be maintained by the addition of more fuel as may be required.
It is to be understood that our invention is in no way limited to the particular
arrangement of pipes and devices for supplying the hydrocarbon, and steam or air
to the generator G, nor to any particular construction of generator G, as these and

page_text: other details of construction may be varied in many ways without departing from
the invention.
In Figs. 3 and 4 we have shown a modification of the generator employed.
Instead of the box or receiver G, we there employ a coil of pipes G¹ which may be
supported upon the bridge wall of the furnace in the rear of the grate. The oil
and steam or air is supplied to the coil G¹ by the pipe I as in the construction
previously described and the generated gases or volatilized products are conducted
to the supply pipes E by the pipe f. The bends of the coil G¹ we prefer to support
upon bars G resting upon the bridge wall and to cover the bends with fire brick or
fire clay, so that they may not be subjected to the excessive heat. The intermediate
portions of the coil G¹ between the bends we prefer to envelope in cast metal
jackets G³, cast upon the pipes G so as to increase their power to resist injury from
the heat. It will be observed that by this construction of generator the heat from
the grate may circulate freely about and between the pipes so that the hydrocarbon
and steam or air within them is more highly heated and gasified and volatilized.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
First. The method of generating heat by the combustion of fuel described
herein, which consists in burning a body of solid fuel such as coal upon a grate,
mixing oil and steam (and air if desired) together and subjecting them when mixed
to the products of combustion of the solid fuel but out of direct contact therewith,
and thereby converting them into combustible gases, leading the combustible gases
thus generated to a point below the body of incandescent solid fuel and allowing
them to escape up into said incandescent body and be consumed therewith.
Second. The method herein before described when air is employed instead of
steam.
Third. The apparatus substantially as hereinbefore described consisting of a
fuel supporting grate, a generator above the grate and at the rear thereof so as to
be subjected to the products of combustion of the fuel on the grate, means to supply
oil and steam or air to the generator, a supply pipe or pipes located under the
grate, and a connecting pipe between the generator and supply pipe or pipes under
the grate.
Fourth. The generator for the purpose described consisting of the coil of pipes G
having the jackets G³ cast upon them.
Fifth. The combination with a furnace grate and generator located above it and
at the rear, of the series of perforated pipes E under the grate, the main F
connecting with the pipes E, and a connecting pipe between the generator and
main F.
Dated this 17th day of May 1893.
WILLIAM LUTHER TETER.
HENRY LAMARTINE WEBSTER.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicants.