CERTAIN IMPROVEMENTS IN THE MEANS OR APPARATUS FOR CONSUMING SMOKE AND ECONOMIZING FUEL IN FURNACES, WHICH IMPROVEMENTS ARE PARTICULARLY APPLICABLE TO FURNACES OF STEAM ENGINES EMPLOYED FOR NAVIGATION AND OTHER PURPOSES
Year: 1835

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
COAD, of Liverpool, in the County of Lancaster, Manufacturing Chemist, send
greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Royal Letters Patent under the Great Seal of Great Britain, bearing
date at Westminster, the Tenth day of July, in the year of our Lord One
thousand eight hundred and thirty-five, and in the sixth year of His reign;
did, for Himself, His heirs and successors, give and grant unto me, the said
Richard Coad, His especial licence, full power, sole privilege and authority, that
I, the said Richard Coad, my executors, administrators, and assigns, or such
others as I, the said Richard Coad, my executors, administrators, or assigns,
should at any time agree with, and no others, from time to time and at all times
during the term of years therein expressed, should and lawfully might make
use, exercise, and vend, within England, Wales, and the Town of Berwick-
upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS IN THE MEANS OR
APPARATUS FOR CONSUMING SMOKE AND ECONOMIZING FUEL IN FURNACES, WHICH
IMPROVEMENTS ARE PARTICULARLY APPLICABLE TO FURNACES OF STEAM ENGINES
EMPLOYED FOR NAVIGATION AND OTHER PURPOSES;" in which said Letters Patent is
contained a proviso, obliging me, the said Richard Coad, by an instrument in
writing under my hand and seal, to cause a particular description of the naturo
of my said Invention, and in what manner the same is to be performed, to be
inrolled in His Majesty's High Court of Chancery within six calendar nionths
next and immediately after the date of the said in part recited Letters Patent,
as in and by the same, reference being thereunto: had, will more fully and at-
large appear..

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Richard Coad, do hereby declare that the nature of my said Invention, and in
what manner the same is to be performed, is particularly described and ascer-
tained in and by the following description thereof, reference being had to the
Drawings, and to the letters and figures marked thereon (that is to say):-
My Invention of Certain Improvements in the Means or Apparatus for Con-
suming Smoke and Economizing Fuel in Furnaces, which Improvements are
particularly applicable to Furnaces of Steam Engines employed for Navigation
and other Purposes," has for its object a more perfect combustion of the
inflamable gases and unconsumed particles of carbon, which in the ordinary
construction of flues pass up the chimney in the form of smoke. This Invention
consists in arresting or regaining a portion of the heat from the vapours emitted
from the combustion of fuel in the furnace during their passage up the chimney,
by an apparatus placed in a part of the flues or chimney beyond the boiler, and
bringing back a portion of the heat (which would otherwise be wasted or lost),
by means of currents of fresh atmospheric air, and introducing the same below
the boiler at or near the bridge of the furnace, for the purpose of consuming
the smoke. The apparatus which I propose to employ consists of air pipes,
tubes, or an air chamber or chambers, placed in or beyond the flue or flues of
the boiler or in the chimney, in such a manner as not to interrupt or interfere
with the draught; or the said air pipes or tubes may be placed in a chamber
situated intermediately between the boiler and the chimney, the said air pipes
being open at one end to the atmosphere, for the admission of currents of
fresh air, such currents being induced either by natural or artificial means,
the other end thereof being open to the furnace at the bridge, as herein-before
mentioned. By these means the fresh air becomes heated in its passage through
the said pipes, tubes, or chambers by the heated vapours proceeding through the
said chamber, flues, or chimney from the fire-place. In order that my Inven-
tion may be better understood, I have hereunto annexed several Diagrams or
Drawings, by way of illustrating the same, and shewing how the said Invention
may be carried into effect; but it is obvious that the principle on which my
improvements are founded admits of considerable variation in the modifications
of apparatus capable of producing similar effects. I am aware that many
plans for consuming smoke and effecting the more perfect combustion of fuel,
and also for supplying heated air to furnaces, have been brought into operation;
for instance, currents of heated air have before been conducted to the bridge of
the furnace and directed upon the burning fucl or gases arising therefrom, but
such air has been heated in a chamber by a separate fire, or by the furnace or
flues of the boiler, by which means the boiler has been injuriously deprived of

page_text: heat by such operation. There have also been plans proposed for abstracting
the waste heat from the exit vapours during their passage up the chimney by
means of currents of fresh atmospheric air proceeding along pipes placed within
the chimney; but the air so heated and abstracted has been employed or
intended to be employed exclusively for supporting the combustion of the fuel.
in the surface by introducing it into an enclosed ash pit, and passing it upward
into the furnace through or between the fire bars ; whereas my-Invention
consists in abstracting the waste heat or caloric from the vapours escaping up.
the flues or chimney, by means of currents of fresh atmospheric air, made to
pass through pipes or chambers placed in or in connection with such flues or
chimnics, and directing the said fresh atmospheric air so heated and obtained
on to the uninflamed smoke or gases arising from the combustion of the fuel at or
near the situation of the bridge of the furnace, for the purpose of promoting a
more perfect combustion of the smoke and inflamable vapours at that point of
its egress. Figure 1 is a vertical section of a furnace, boiler, and flues, taken
longitudinally, for the purpose of shewing a method of carrying my said Inven-
tion into effect by means of coiled pipes placed in the chimney, which pipes are
open at one end to the atmosphere, and at the other end to the interior of the
furnace, at or near the top of the bridge. A is the boiler; B, the fire-place or
furnace; C, the fire bars; D, the bridge; E, E, the flues; F, the chimney; G, G,
a series of pipes or tubes, of iron or other suitable metal, the outer extremities of
which pipes or tubes are passed through the side of the chimney, and are open to
the atmosphere. These said pipes should in every case have such a number of
coils given to them, and present such a surface to the action of the heated air
and gasses passing up the chimney, as would render them capable of absorbing
the available heat. The lower extremities of the said pipes lead into a larger
tube H, H, which forms a passage to the bridge D, and there terminates in a
long narrow slot or opening, or a series of small openings, at or near the top of
the bridge, so as to direct a current of fresh air upon the uninflamed smoke,
where, by means of this current of fresh heated air, a more perfect combustion of
the smoko is effected. In cases where the draught of the chimney is not suffi-
ciently strong to induce the required current of atmospheric air to pass through
the said pipes, so as to enable the smoke to be effectually consumed, I employ a
wind fan or other mechanical means for forcing a proper quantity of air through.
the said pipes. Figuro 2 shews another method of carrying my said Invention
into effect, in which a series of bent pipes G, G, are placed nearly vertically
in the chimney, instead of in coils, as represented in Figure 1. The outer
ends of the pipes G, in this instance, are open to a chamber I, I, under the
ash pit, where, the air will receive a partial warmth before it enters the pipes G.
"

page_text: The same letters of reference being marked on the corresponding parts in this
and the following Figures, as also in Figure 1, no further description will be
necessary. Figure 3 shews another mode of effecting the same object by a
series of short tubes G, G, placed horizontally across an enlargement of the
chimney at its lower part, one end of each of the said tubes communicating
with the chamber K, which said chamber is open to the atmosphere by the
short pipe L; the other ends of the said short pipes terminate in the chamber
M, from which the pipe II descends and passes to the bridge. In the said
Figure 3, I have represented the manner of employing a wind fan, which is
shewn at N. In adapting my said Invention to the furnaces of steam boilers
of marine or locomotive engines, I prefer using a hot air chamber at the lower
end of the chimney, as shewn in a sectional elevation at Figure 4, and in a
horizontal section at Figure 5, with tubular flues passing through the hot air
chamber. F, F, is the chimney or funnel; D, D, a cylindrical chamber
introduced into the chimney, resting on brackets; P, P, represent a number of
vertical pipes or tubular flues carried through the cylindrical chamber for the
passage of the hot vapours and gases from the furnace to the chimney;
Q, Q, are short pipes for the admission of atmospheric air into the chamber D,
which air, after having become heated by its passage between the pipes P, P, P,
within the chamber, proceeds through the larger tube R, which is connected by
a cone and socket to the pipe H, and is discharged at the bridge of the
furnace for the purpose of inflaming the smoke, as herein-before mentioned.
In witness whereof, I, the said Richard Coad, have hereunto set my
hand and seal, this Twenty-third day of December, in the year of our