IMPROVEMENTS IN FURNACES FOR BURNING CANE TRASH AND OTHER FUEL
Year: 1881

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for an Invention of "IMPROVEMENTS
IN FURNACES FOR BURNING CANE TRASH AND OTHER FUEL." A communi-
cation from abroad by Marie Jean Léon Marie, of Saint Pierre, Martinique.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark
at the Office of the Commissioners of Patents on the 9th March 1881.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "IMPROVEMENTS IN FURNACES FOR BURNING CANE
TRASH AND OTHER FUEL." [A communication from abroad by Marie Jean Léon
Marie, of Saint Pierre, Martinique.]*
This Invention relates to an improved furnace for burning bagasse or cane trash,
shavings, or other fuel, so constructed that the fuel, which is generally very moist,
is dried before being burned by the radiant heat from the walls of the furnace,
thereby ensuring perfect combustion. The furnace is exterior to the boiler, and the
boiler furnace thus merely receives the gases of combustion from the bagasse
furnace which is complete in itself, has a natural draft, and is capable of being
readily connected to any boiler by one or more flues in the sides or crown of the
furnace, and of standing in any position with regard to the boiler, as circumstances
may require.
This improved bagasse furnace is constructed preferably of cast iron encased in
brickwork, and consists of a rectangular chamber formed of cast iron plates bolted
together by flanges, and stiffened by ribs. The bagasse furnace has a pyramidal
shaped crown surmounted by a hopper through which fuel is fed into the furnace,
the said hopper being furnished with a self acting balance door or valve so arranged
that it only permits a quantity of bagasse or other fuel corresponding to the balance
weight (which is adjustable) to fall into the furnace at one time. The furnace is
furnished at the lower part with a grate inclined downwards from front to back,
which extends at the lower part through an opening in the rear wall of the furnace,
the fire bars being supported at their lower ends by a bridge or plate bolted to
cheek plates or extensions of the side walls of the furnace. The said opening and
bridge are made as wide as possible, and are situated just below the boiler furnace,
Drice 971

page_text: to which the bagasse furnace is connected by a flange surrounding the said opening,
and fitting in the doorway of the boiler furnace, the interval between the two being
built up with firebricks and fire clay, and all communication between the boiler
furnace and the exterior air being prevented. The bagasse furnace is furnished
with double doors at the front, on a level with the upper end of the fire grate, with
double doors which permit the examination of the fire upon the bars, and the
introduction of the quantity of coal necessary for initiating and maintaining the
combustion of the bagasse. The cast iron sides of the bagasse furnace may be lined
with fire brick or fire clay at the parts just above the grate bars most exposed to
the heat, or the whole interior may be so lined to enable the furnace to withstand
the greater heat given out by coal which might be burnt when the supply of
bagasse runs short.
Although exterior to the boiler, this improved bagasse furnace has greater
heating power than an internal furnace, as bagasse coming wet from the mill
requires to be dried to render it fit for fuel, and this preliminary drying it receives
in this improved furnace. A coal fire having been first lighted in the furnace, its
walls become highly heated; the wet cane trash is then fed in through the hopper,
whose balance door opens to give passage to and spread the trash uniformly upon
the grate, the door closing again immediately to re-establish the natural draft
through the grate. The flame of the fire immediately envelops the fresh fuel, and
owing to the high temperature in the furnace the gases at once begin to be
distilled. As the surfaces of internal furnaces do not exceed the relatively low
temperature of the surrounding water, a great part of the gases is carried off
unconsumed, and becomes partly condensed on the cooler surfaces, and partly
passes away unconsumed in the form of smoke, whereas in this improved furnace
the heat which in the former case would go to heat the water is stored up in the
walls of the furnace, which quickly become hot enough to almost instantly dry the
bagasse, and render it eminently fit for burning. As all the gases are compelled to
pass through the contracted aperture leading to the boiler furnace, the combustion
of any as yet unconsumed products is ensured. Owing to the perfect combustion
thus obtained, there is little or none of the usual deposit in the boiler flues.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Great Seal Patent Office on the
9th September 1881.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "IMPROVEMENTS IN FURNACES FOR BURNING CANE
TRASH AND OTHER FUEL." A communication from abroad by Marie Jean Léon
Marie, of Saint Pierre, Martinique.
This Invention relates to an improved furnace for burning bagasse or cane trash,
shavings, or other fuel, so constructed that the fuel, which is generally very moist,
is dried by the radiant heat of the furnace before being burned, whereby perfect
combustion is ensured. This bagasse furnace is exterior to the boiler or other
furnace to which it is connected, and which merely receives the gases of combustion
from the bagasse furnace. The latter is complete in itself, has a natural draft, and
is capable of being readily connected with any boiler by one or more apertures in
the sides or crown of the bagasse furnace, and of standing in any position with
regard to the boiler as circumstances may require.
This improved bagasse furnace is constructed either of cast iron, wrought iron,
or other metal, but preferably of cast iron encased in brickwork. It consists of a
rectangular chamber having a pyramidal shaped crown surmounted by a hopper,
through which fuel is fed into the bagasse furnace, the said hopper being furnished
with a self acting balance door or valve so arranged that it only permits a quantity
of bagasse or other fuel corresponding to the balance weight (which is adjustable)
to fall into the furnace at one time. The furnace has a grate inclined downwards
from front to back, and extending at the lower part through a mouth or opening
equal to the whole or nearly the whole width of the rear wall of the furnace, the
fire bars being supported at their lower ends by a bridge or plate bolted to cheek
plates or extensions of the side walls of the furnace. In applying the bagasse
furnace to a stationary boiler of the locomotive pattern, for example, the said
mouth or opening and bridge would be situated just below the fire box of the
boiler, from which the fire bars would be removed. A flange surrounds the upper
part of the said mouth or opening, and may fit in the doorway of the fire box.
The bagasse furnace is furnished with double doors at the front, on a level with
the upper end of the fire grate, to permit the examination of the fire upon the bars,
and the introduction of the quantity of coal necessary for initiating and maintaining
the combustion of the bagasse. The cast iron sides of the bagasse furnace may be
lined with fire brick or fire clay at the parts just above the grate bars most
exposed to the heat, or the whole interior may be so lined, to enable the furnace to
withstand the greater heat given out by coal, which might be burnt when the
supply of bagasse runs short,
In order that the Invention may be more readily understood, I will proceed to
describe it with refereuce to the annexed Drawings, in which Figure 1 represents
a front elevation; Figure 2, a longitudinal vertical section; Figure 3, a rear
elevation; and Figure 4, a horizontal section of the bagasse furnace. Figure 5
represents by way of example the furnace as applied to the fire box of a boiler of
the locomotive pattern. The same letters of reference indicate the same parts in
all the Figures.
A is the furnace chamber constructed preferably of cast iron plates a stiffened by
ribs a', and bolted together by flanges a². B is the pyramidal shaped crown of the
furnace chamber, also constructed of cast iron plates bolted upon chamber A, and
surmounted by the hopper C in which the bagasse is dried, and through which it is
fed to the furnace. D is the self acting balance door or valve placed within the
hopper in the inclined position shown. It works on pivots at d supported in the
sides of the hopper, one of them having a lever arm d¹ fixed to it outside the
hopper, upon which is placed a counterweight D', adjustable along the arm d¹, to

page_text: regulate the quantity of bagasse admitted each time the door opens. E are the
fire bars at the lower part of the furnace A. They are inclined as shown, and their
lower ends extend through on opening F, and are supported by an inclined bridge G
bolted to extensions as of the side walls of the furnace. The upper part of this
opening is surrounded by a flange g which may fit in the doorway or beneath the
fire box of the boiler, the form and dimensions of said flanged opening or throat
being varied as circumstances may require. H are doors just above the fire bars
for giving access to the furnace.
As shown in Figure 5, the chamber A and crown B would be encased externally
in brickwork, and the sides a or the most exposed parts thereof would be lined
internally with firebrick or fire clay; the walls O which support the boiler may
also be faced with firebricks. The bagasse furnace is here shown as supported on
feet I at front, and at back upon a wrought iron girder K, whose ends are built
into the walls that support the fire box of the boiler. The lower part of the boiler
fire box is completely closed by brickwork L supported on girders built into the
same side walls, and the interval between the bagasse furnace and the fire box
being also built up the whole of the air to support combustion must come in
through the fire bars E.
Although exterior to the boiler, this improved bagasse furnace has greater heating
power than an internal furnace, as bagasse coming wet from the mill requires to be
dried to render it fit for fuel, and this preliminary drying it receives in this
improved furnace. A coal fire having been first lighted in the furnace A, its walls
become higbly heated; the wet cane trash is then fed in through the hopper C,
whose balance door D opens to give passage to and spread the trash uniformly
upon the grate E, the door D closing again immediately to re-establish the natural
draft through the grate E. The flame of the fire immediately envelops the fresh
fuel, and owing to the high temperature in the furnace the gases at once begin to
be distilled. As the surfaces of internal boiler furnaces do not exceed the relatively
low temperature of the surrounding water, a great part of the gases is carried off
unconsumed, and becomes partly condensed on the cooler surfaces, and partly passes
away in the form of dense smoke, whereas in this improved furnace, the heat which
in the former case would go to heat the water is stored up in the walls of the
furnace, which quickly become hot enough to almost instantly dry the bagasse,
and render it eminently fit for burning. As all the gases are compelled to pass
through the mouth or aperture leading to the boiler furnace, perfect combustion is
ensured, and there is little or none of the usual deposit in the boiler tubes.
Having described the nature of the said Invention, and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
hereinbefore in part recited Letters Patent is,-
1st. The construction, combination, and arrangement of parts of the bagasse
furnace, substantially as herein shown and described.
2nd. A bagasse furnace constructed as herein described to adapt it for connection
and use with a boiler or other furnace, substantially as shown and described.
3rd. The combination with the fire box of a boiler of an external furnace, con-
structed and arranged as herein described for burning bagasse or other moist fuel,
the boiler furnace receiving the products of combustion from the bagasse furnace as
described.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set