Improvements in Boiler and Metallurgical Furnaces, and in the Method of Heating the same.
Year: 1895

page_text: Date of Application, 15th Jan., 1895-Accepted, 16th Feb., 1895
COMPLETE SPECIFICATION.
Improvements in Boiler and Metallurgical Furnaces, and in the
Method of Heating the same.
I JAMES WILLIAM MCGEANAHAN, of 258 West 29th Street, New York City,
United States of America, Mason 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 :-
My invention relates to furnaces for heating boilers, reverberatory and open
hearth furnaces and similar structures. According to my invention the fire is
burned on a grate situated at some distance from where the heat is to be applied.
Such grate may be of the ordinary type of step grate or of the kind used in
Siemens' furnaces, the object being to provide a quantity of incompletely burned
and therefore combustible gases. The stream of gas produced in the grate is led
through flues to the fire box of the boilers, or to the bed of the furnace or other
place where the heat is desired to be generated. Thus, beneath the boilers or in
the furnace I maintain a clear gas fire, all ashes and dirt of every description
being far removed therefrom. If now, air were supplied directly to the fire
chamber from the outside there would be a great waste of heat owing to the
inevitable cooling of the gases from the fire on their way through the flues to the
fire chamber. To avoid such loss of heat I conduct the air required for the com-
bustion of the gases through flues or heaters contiguous to the smoke or gas flues,
the walls of which air flues or heaters become highly heated by the gas.
heats the air, and supplies for the combustion of the gas in the fire chamber, a
stream of highly heated air.
This
My invention consists of certain features of construction and combinations of
parts that will be hereinafter described and claimed.
Reference is to be had to the accompanying drawings forming a part of this
Specification, in which similar letters of reference indicate corresponding parts in
all the figures.
Figure 1 is a horizontal partly sectional view of my improved furnace ;
Figure 2 is a vertical and longitudinal, partly sectional view of the same;
Figure 3 is a vertical cross section showing the arrangement of air and gas flues
in what I term the reheating portion of my device; and
Figure 4 is a cross section showing the perforated bridge wall.
The section of Figure 1 follows the dotted line 1-1 of Figure 2. The section
of Figure 2 follows the dotted line 2-2 of Figure 1. The section of Figure 3
follows the dotted line 3-3 of Figure 2. The section of Figure 4 follows the
dotted line 44 of Figure 2.
A, is the grate fed with coal through the fire doors by regular process. From
the grate the combustible gases go through the flues B, B, following the course of
the arrows and reaching the furnace by the centrally disposed flue C in which the
several gas flues unite. The air enters by flue openings D, D, and in the
reheaters E, E, follows as forced to by the diaphragms and walls, a sinuous course
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page_text: up and down through the heaters and finally by the flues F, F, reaches the
perforated bridge wall G, where it is admitted to the fire chamber.
The gases to be delivered to the fire chamber enter it by a flue or upcast H,
reaching up through its floor. The air for the combustion of the gases reaches
the fire chamber through a similar. flue perforated to permit the outflow of the air,
and so arranged as to constitute a bridge wall. As the hot gases rush into the
chamber through the up-cast H they are met by a stream of air from the flue or
perforated bridge wall F. Combustion takes place, its intensity being greatly
increased by the heating of the air. The result is a very pure flame absolutely
void of all ashes and solid matter. The draft of air may be accelerated if desired,
by the use of a blower, or a chimney of the ordinary construction may be used to
maintain the necessary current through the heater and connecting flues. The
ordinary devices may be used to admit extra or cold air to the fire chamber of the
boiler by adjustable ports or dampers on its front or sides, the use of such, however,
forming no part of this invention.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what 1
claim is,-
1. The combination of the grate A, the side and central gas flues B, and air
heaters E located between said gas flues, substantially as shown and described.
2. In a gas generating apparatus, the combination of smoke and gas flues, with
independent and separate air flues, adjacent thereto, so arranged that the heat of
the gas heats the walls of the air flues substantially as described and illustrated.
3. The method of heating a boiler or furnace, which consists in supplying
combustible gases from a fire, and burning such gases in a separate combustion
chamber or fire-box, and in causing such gases on their passage to such combustion
chamber to heat the air on its way thereto substantially as described and illustrated.
4. The combination with the fire-place, of a plurality of parallel gas flues
arranged in the rear of the fire-place, and separate air chambers extending longi-
tudinally of the gas flues and arranged between each two gas flues, said chambers
being provided with vertical alternately overlapping diaphragms to produce
sinuous channels for the air to compel it to travel alternately up and down while it
proceeds from one end of each chamber to the other end thereof, substantially as
described.
5. The combination, with the fire-place of a plurality of gas flues arranged in
the rear of the fire-place, air chambers extending longitudinally between the said
gas flues and provided with diaphragms to produce sinuous channels for the air, a
gas flue into which discharge the aforesaid gas flues, a combustion chamber into
which discharges the said gas flue, a perforated bridge wall located in the said
combustion chamber, and air flues connecting the air chambers with the said bridge
wall, substantially as described.
Dated this 15th day of January 1895.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.