An Improved Apparatus for the Prevention and Consumption of. Smoke and more Complete Combustion of Fuel in Steam Boiler and other Furnaces.
Year: 1888

page_text: Date of Application, 24th Jan., 1888
Specification Accepted, 24th Feb.,
1888
An Improved Apparatus for the Prevention and Consumption of.
Smoke and more Complete Combustion of Fuel in Steam Boiler
and other Furnaces.
#
I ALFRED DON of No. 21 Cooper Street Redfern in the Colony of New South
Wales Engineer do hereby declare the nature of my invention for AN IMPROVED
APPARATUS FOR THE PREVENTION AND CONSUMPTION OF SMOKE AND MORE COMPLETE
COMBUSTION OF FUEL IN STEAM BOILER AND OTHER FURNACES, and in what manner
the same is to be performed, to be particularly described and ascertained in and by the
following statement :-
My invention consists of an improved and novel construction, and arrangement of
parts, of an apparatus for the prevention and consumption of smoke and more com-
plete combustion of fuel in steam boiler and other furnaces, by the aid of a steam
jet and an induced current of air, the same constituting an improved, simple and
most efficient apparatus, which can be applied with the greatest facility, and at a
nominal cost, to any steam boiler furnace, or other furnace to which the same may be
adapted without alteration in the structure thereof.
Numerous devices have heretofore been resorted to having for their object the
prevention or consumption of smoke in steam boiler and other furnaces, and the
increase of combustion of fuel therein, but the same have been for the most part
costly and complicated in themselves, or have required for their application and
operation a special construction, or an alteration of the furnace, and many of such
inventions, and others of a more economical character, have only been partially
effective.
The introduction into such furnaces of air, either cold or heated, or of steam and
air combined, and the use of steam jets, are known to aid in preventing or
diminishing smoke and increasing combustion, but the apparatus heretofore employed
for such purposes, and the methods of applying the same have either not ensured
complete success; or if successfully used the apparatus employed has not possessed
the cheapness, efficiency, and simplicity, with the facilities for the application and
operation thereof, which are incident to my invention.
In carrying out my said invention 1 construct a metal pipe, of particular dimensions

page_text: as hereinafter mentioned which is secured to the end of the furnace. The same is
formed with a bell shaped mouth at the top or upper end thereof, and is bent or
curved at the lower end so as to adapt it to enter the firebox at or immediately
above the furnace door. The lower extremity is formed with a bell shaped exit of
such length as to project slightly beyond the inner shell of the firebox, and the same
is constructed with a slight downward deflection. The faces of the said bell-shaped
exit are formed at such angles that lines produced therefrom will reach all the sides
or angles of the firebox opposite thereto, just above the level of the fuel therein, so
that jets of steam and induced currents of air, passing through the pipe, will by
means of such bell-shaped exit, constructed as aforesaid, be projected equally all over
the fuel.
A steam pipe of about half an inch in diameter is bent at its lower end, corre-
spondingly with the curved portion of the air pipe, and is passed into such pipe so
that its exit is just beyond the bend or curve of the latter pipe, and it is fixed within
the air pipe.
For application to a steam boiler furnace the said steam pipe is extended upwards
along and over the end of the furnace, to a connection with the steam chest, and it
is operated at or near such connection by a suitable steam cock or valve.
A valve or lid is fixed at the top of the air pipe to admit or exclude air from the
pipe as required.
The said apparatus is illustrated in the accompanying drawings in which Figure 1
represents a vertical sectional side elevation of the furnace of an ordinary locomotive
boiler, with the complete apparatus used by me affixed thereto.
Figure 2 the end elevation of the furnace showing how the upper part of the steam
pipe portion of the said apparatus clears the regulating valve.
Figure 3 is a side elevation of the principal portion of the said apparatus.
Figure 4 is a view thereof in section.
And Figure 5 is a plan shewing the mouth of the air pipe of the said apparatus
with valve fitted thereon.
Like letters indicate the same parts throughout the various views.
In the said drawing B. represents the furnace door, C the air pipe, the same being
secured to the furnace and entering the firebox as shown in Figure 1. D represents
the steam pipe fixed in the air pipe, and extending upwards to the steam chest.
E, the cock or valve to control the supply of steamı.
I construct the air pipe C preferably of cast iron, and the same is provided with
lugs or eyes at suitable distances along its stem to receive bolts or screws to secure it
to the end of the furnace.
The said pipe may be of any suitable contour, but I construct the samel preferably
of an oval shape. For application to the furnace of an ordinary locomotive boiler of
the dimensions of four feet five inches by three feet eight inches, I construct the said
pipe eighteen inches in length from the top or mouth of the pipe till the bend or
curve therein hereinafter mentioned (although that precise length is not very material)
and of a diameter of four inches by two and a half inches. Although the said
diameter may be slightly exceeded or diminished with approximately the same result
in operation, I have found in practice that for such furnace a pipe with a larger or
smaller area is not as effective as one of the area specified.
The said air pipe C is formed with a bell shaped mouth at the top or upper end
thereof. For application to the furnace of a locomotive boiler the lower part of the
said pipe is bent or curved at or nearly a right angle with its stem, as shewn in the
drawing, so as to adapt it to enter the firebox as hereinafter mentioned. For appli-
cation to the furnace of a marine boiler the lower part of the said pipe is formed in
like manner, but with a slight deflection. The lower extremity is formed with a
bell shaped exit. I construct the same for a pipe of the before mentioned dimensions
with an angle of deflection of about three fourths of an inch, and of the dimensions of
about six inches by three inches, and so that the curve or bend of the pipe allows the
said exit to extend about one and three quarter inches beyond the inner shell of the
firebox.

page_text: For larger furnaces such as those of marine boilers and others to which the said
apparatus may be adapted the pipe must have a larger diameter in the like proportion
to the size of the furnace and the bend of the pipe as well as the deflection of the exit
will be varied to accommodate the apparatus to such larger furnaces.
The faces of the said bell shaped exit are formed at such angles that lines produced
therefrom will reach all the sides or angles of the firebox opposite thereto just above
the level of the fuel therein, so that jets of steam and induced currents of air passing
through the pipe will by means of such bell shaped exit constructed as aforesaid be
projected equally all over the fuel.
The steam pipe D is constructed preferably of copper and about half an inch in
diameter. It is bent at its lower end correspondingly with the bent or curved portion
of the air pipe Cand is passed into such pipe so that its exit is just beyond the bend
or curve of the latter pipe, and it is fixed within the said pipe either in the centre
thereof by suitable stays or brackets as shewn in Figure 4, or fixed in any other part
of the pipe in any other way.
The said steam pipe D is extended upwards along and over the end of the furnace
as far as possible so as to ensure the dryness of the steam it is to convey to a connec-
tion with the steam chest, as appearing in Figures 1 and 2, and is controlled at or
near such connection by a suitable steam cock or valve E. The same is shewn in the
drawings as fixed on an Adams safety valve.
A steam trap of any approved form may be fitted at any part of the steam pipe
between the steam cock E and the mouth of the air pipe 1) to aid in securing dry
steam.
A valve or lid as shewn in Figure 5, or of any other suitable and preferred con-
struction, is provided for the mouth of the air pipe C to admit and exclude air from
the pipe as required.
In the furnace door of a locomotive furnace, centrally of its upper edge, I cut or
form an opening suited to admit the passage of the lower curved portion of the
air pipe C so that when the door is closed an approximately tight joint is formed
between it and the said pipe. In other steam boiler furnaces I provide such opening
in the dead plate immediately above and in the centre of the door.
The air pipe C is placed against the end of the furnace so that its curved portion
projects within the firebox, and it is secured in place by bolts and screws passed
through the lugs or eyes, or the latter may be dispensed with and any other proper
means be adopted to hold the pipe in place.
When it is desired to avoid any smoke from the furnace before steam is got up, or
if it is desired to hasten the making of steam, the apparatus may be employed by the
use of steam from another source with the necessary appliances for the purpose.
The said apparatus can be readily applied to any steam boiler furnace, and other
furnaces to which may be applicable, at a nominal cost, and without alteration
therein except the aperture made in or at the top of the furnace door.
By opening the lid or valve of the air pipe and then turning on the steam, a jet of
steam in the pipe D and a current of air induced thereby in the pipe C passing into
the firebox will have the effect with careful stoking of almost immediately dispersing
any smoke and of preventing smoke being generated by fresh fuel and also within a
few minutes of rendering the fuel incandescent, when the steam can be turned off.
I have found in practice that with careful and proper stoking the use of the steam
jet as mentioned after or at the time of adding fuel will generally have the effect
within a few seconds of time of dispersing any smoke and of preventing further smoke
being generated, and within a few minutes, varying from two to five minutes, of
rendering the fuel incandescent. In cases where the fuel added is bulky of itself or
is introduced in greater quantity a longer time may be required for the latter
purpose.
The operation of the said apparatus as before mentioned is attended with the
further result of securing a great economy in the consumption of fuel.
I attribute the effect resulting from the use of the said apparatus adjusted as

page_text: aforesaid in part to the current of air induced in the air pipe by carrying the steam
pipe down the full length thereof just beyond the bend or curve therein; in part to
the temperature of the atmosphere entering the furnace through the said means, being
that suited for the desired object, not too hot to diminish materially the supply of
oxygen and sufficiently warm to obviate the disadvantages incident to the introduction
of cold air into a furnace ; in part to the quantity of air introduced into the furnace
within the time the apparatus is used the same being that suited for the required
purpose it being found in practice that the introduction of a lesser or greater quantity
of air is not attended with the same result; and in part to the bell-shaped exit of the
air pipe constructed and adjusted as before mentioned.
The said apparatus is of course available for such furnaces other than steam boiler
furnaces as are of a construction to admit of the same being adapted thereto.
The said apparatus might be varied in form by the use of an air induction pipe
without bend or curve at its lower end or of an air induction pipe wholly curved, or
in any other form, so long as the area of the pipe constructed with such diameter as
aforesaid is of the dimensions hereinbefore stated, or approximately so, for application
to the furnace of a locomotive boiler of the size before mentioned, and for application
to larger furnaces with a diameter in like proportion to the size and fuel capacity of
the furnace, with the adoption of any suitable contrivance whereby the same may be
applied to a furnace, so as to discharge a jet of steam and an induced current of air
over the whole surface of the fuel, so long as there is a corelative prolongation of the
steam pipe. If the air pipe used should be straight the prolongation of the steam
pipe for about two-thirds of its length would suffice. If the air pipe should be curved
it would be necessary to carry the steam pipe beyond the extreme bend or curve
thereof so that the outlet of the steam pipe should be within the precise line of the
outlet of the air pipe. I have, however, found that my invention is most efficiently
and conveniently carried out by the use of a pipe bent or curved at the lower end
thereof as hereinbefore described.
The said apparatus might also be varied by carrying the steam pipe along the
outside of the air pipe bent or curved at the lower end and constructed as herein-
before described and then inserting the steam pipe, or by otherwise inserting a steam
pipe otherwise adjusted into the lower portion of such air pipe with approximately the
same result so long as the steam pipe is carried just beyond the bend or curve in the
air pipe and constructed so that its outlet is in the same line as the outlet of the air
pipe. And if an air pipe of any other shape were used and applied to a furnace by
suitable means the insertion of the steam pipe into the air pipe at the point to which
the steam pipe would be carried if placed within the air pipe with the like construction
of the outlet of the steam pipe the effect would be the same. I have found, however,
that my invention is most conveniently and efficiently carried out by carrying the
steam pipe through the air pipe.
Having thus described the nature of my said invention and how the same is carried
into effect I have to state that I make no claim to the use of an air induction pipe
either straight or bent or curved at its lower end to adapt it to enter a furnace nor to
the combination of an air induction pipe with a steam supply pipe, nor to the
connection of such steam supply pipe with the steam chest of a locomotive boiler, but
what I claim is
1. The combination with an air induction pipe having a bell shaped mouth fitted
with a lid or valve, and its lower portion bent or curved to project within the fire box
of a steam boiler furnace, or other furnace to which the same may be adapted, of the
bell shaped exit thereto deflected downwardly, and constructed substantially as
described to discharge air and steam over the whole surface of the fuel, and of a
steam pipe, carried or fixed just beyond the bend or curve of the lower portion of the
said air pipe substantially as described and for the purposes set forth.
2. The construction of an air induction pipe (with or without its lower portion ben
or curved to project within the firebox of a steam boiler' furnace, or other furnac

page_text: to which the same may be applicable) with a bell-shaped exit thereto deflected
downwardly and constructed substantially as described so as to discharge air and
steam over the whole surface of the fuel for the purposes set forth.
3. In the combination as part of a smoke consuming apparatus of an air induction
pipe with a steam supply pipe, the prolongation of the steam pipe (if passing into
the mouth of the air pipe) just beyond the bend or curve of the air pipe, if bent or
curved at its lower end, or for about two-thirds of the length of the air pipe if
straight in form, or beyond the extreme bend or curve of the air pipe if curved in
form, substantially as described; or if the steam pipe should not pass into the
mouth of the air pipe, the insertion thereof into the air pipe at the point to which
it would be carried as before stated if placed within the air pipe and constructed so
that the outlet thereof is within the precise line of the outlet of the air pipe
substantially as described and for the purposes set forth.
Haseltine, Lake & Co.,
A. DON.
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.