Used therewith, and in Utilising Solid and Gaseous Fuel therein.
Year: 1885

page_text: Used therewith, and in Utilising Solid and Gaseous Fuel
therein.
I JAMES THEODORE GRIFFIN of 36 Worship Street, Finsbury, London, Agricul-
tural Engineer (a communication from abroad by Jesse W. Hatch of North Water
Street Rochester, New York, U.S.A. Manufacturer) do hereby declare the nature of
the said invention to be as follows:-
This invention relates to fitting within or alongside a Furnace one or more
drums of segmental shape in which raw fuel can be coked by heat from the fire,
the gases and products of combustion arising from said raw fuel being free to pass
into the ashpit or other convenient space for entry into and through the fuel on
the furnace bars for utilization said raw fuel being by this means coked and
the drum or drums move round for discharging it or their contents onto the
furnace bars.
The drums are provided with end doors by which they can be charged with raw
fuel in a similar manner to retorts and be turned from the outside both to close
their segmental openings against the furnace proper or into it.

page_text: Improvements in and relating to Furnaces, in Apparatus to be
Used therewith, and in Utilising Solid and Gaseous Fuel
therein.
I JAMES THEODORE GRIFFIN of 36 Worship Street, Finsbury, London Agricul-
tural Engineer, do hereby declare the nature of this invention which has been
communicated to me from abroad by Jesse W. Hatch of Rochester, New York,
United States of America, and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement:—
This invention relates to fitting within or alongside a Furnace one or more
drums in which raw fuel can be coked by heat from the fire, the gases and products
of combustion arising from said raw fuel being free to pass into the ashpit or other
convenient space for entry into and through the fuel on the furnace bars for
utilization said raw fuel being by this means coked and the drum or drums move
round for discharging it or their contents onto the furnace bars. The drums are
provided with end doors by which they can be charged with raw fuel in a
similar manner to retorts and be turned from the outside both to close their
openings against the furnace proper or into it.
The main object of this invention, which will be understood by reference to the
annexed drawings, relating to furnaces is to ensure the more complete combustion
of fuel and afford a greater amount of heat from a given amount of fuel than has
been heretofore attained, the invention being especially applicable to furnaces using
bituminous coal or other fuel having a large proportion of volatile or gaseous
matter which by the ordinary methods is not usually completely consumed, but is
delivered from the furnace in the form of smoke or unconsumed gases, not only
wasting the heat which might be derived from the said smoke, if properly con-
.sumed, but also vitiating the surrounding atmosphere..
My invention is embodied in a furnace having, in addition to the usual fire-
chamber, in which the solid fuel burns on a suitable grate, combining with air
introduced through the said grate from below, auxiliary chambers, ovens or retorts
normally having no direct communication with the fire chamber above the grate,
but communicating with flues or passages leading to the space below the grate
where the air is introduced to combine with the fuel burning on the grate. These
ovens are provided with doors or openings, into which the solid fuel--such, for
example, as bituminous coal or wood-is introduced, and the ovens are exposed to
the heat of the fire so that the fuel contained therein is roasted and the more
volatile products, consisting of water or steam and various combustible gases, are
conveyed by the flues before mentioned to the space below the grate, where they
mingle with the air and pass through the grate, and are thus thoroughly consumed
in connection with the solid fuel, thereby greatly increasing the heat in the fire
chamber. Means are provided for placing the ovens or retorts in direct communi-
cation with the fire chambers, and after the volatile portions have been removed
from the fuel in the ovens and consumed, as previously described, communication
is established between the retorts and the fire-chamber, permitting the solid portion
of the fuel remaining in the retorts to be discharged therefrom into the fire chamber

page_text: or upon the grate, the said fuel delivered from the ovens approaching more or less
the condition of coke.
The retorts or ovens are preferably cylindrical, and are capable of a rotary move-
ment, the fuel being introduced at the end of the cylinder, which has a lateral
passage or opening that may be placed in communication. with the flue for dis-
charging the volatile portion of the fuel or in communication with the fire chamber
for discharging the solid portions of the fuel on to the grate.
Figure 1 is a sectional elevation and Figure 2 a front elevation of a furnace
embodying this invention, shown as employed for the generation of steam in a
boiler and Figure 3 is a central longitudinal section thereof.
The main portion a of the furnace, and the fire chamber 6 therein, accessible by
doors c in the furnace front, and the grate.d and ash pit e below the same, and
doors affording access to the said ash pit, and admitting air to support com-
bustion of the fuel may be of any suitable or usual construction, the body of the
furnace being shown as of masonry and supporting a boiler or steam generator g
to be heated by the fire burning on the grated and the products of combustion
derived therefrom.
The furnace is provided with one or more chambers, ovens.or retorts, h, shown
as cylindrical in shape, and mounted on a shaft, i, the said chambers being acces-
sible from the front of the furnace by doors k through which the fuel is introduced
to the said chambers. These fuel chambers, ovens, or retorts are provided with
openings m which normally communicate with the flues or passages n in the
furnace leading to the space below the grate d and the said chambers are placed
within the fire chamber b and exposed to the heat of the fire burning on the
grate d so that the fuel introduced to the chamber his roasted, causing the more.
volatile portion, consisting largely of water and combustible gases, to be driven off
from the said fuel, the said volatile portions escaping through the openings m and
passing through the flue n into the space below the grate, and, passing through the
fuel on the grate, are consumed, thus adding to the heat derived from the said fuel
that is burning on the grate. After the fuel in the chamber h is exposed a sufficient
length of time to the heat of the fire to thus drive off and consume the greater
part of the volatile constituents of the fuel, reducing it more or less nearly
to the condition of coke, the said fuel is discharged into the fire chamber and
burns on the grate d in the usual manner. In order to thus discharge the fuel
from the chambers h into the grate, the said chambers are provided with handles p
by which they may be turned on their journals, so as to bring the openings m of
the said chambers into the chamber b in position to discharge the fuel from the
said chambers h which are shown as provided with flat partitions or floors r
extending to the edge of the opening m, from which floors the fuel will slide on
to the grate d. After the solid fuel has been thus discharged into the furnace from
the chambers the latter are restored to their normal position as will be under-
stood by reference to Figures 1 and 2 and fresh fuel is introduced through the
doors and permitted to roast and become heated as before described, before being
discharged into the fire chamber or furnace proper; and it will be seen that the
fuel is introduced to the furnace without opening a door or providing a direct
passage to the space above the grate, as usually occurs when fresh fuel in introduced
through the doors c as usually practiced.
When fresh fuel is thrown directly upon the fire already burning in a furnace,
as usually practiced, the fresh fuel cools that which is already burning, and before
becoming thoroughly ignited will have its volatile products roasted or driven out,
and such products being above the fire, and not being provided with sufficient
oxygen for proper combustion, will pass off through the chimney in the form of
smoke or vapor, thus not only wasting the heat which might be derived from
their combustion, but also vitiating the surrounding atmosphere to a needless
extent.
In the herein described furnace, on the other hand, the volatile portions of the
fuel before arriving at the chimney have to pass through the highly heated fuel

page_text: burning on the grate, in connection with sufficient air to ensure perfect combustion,
so that the maximum amount of heat is derived from the fuel passing through
the fire chamber without giving out smoke or unconsumed gases, and, furthermore,
the solid fuel, when finally discharged upon the grate, is highly heated, and will
thus become ignited at once without materially lowering the temperature of the
fuel that is already burning.
The invention is not limited to the particular construction of the ovens herein
shown nor to the means.provided for discharging the fuel from the said ovens into
the fire chamber the essential feature of this part of the invention being that
the ovens have no direct communication with the fire chamber while the fuel is
being introduced into the said ovens and roasted therein. If desired, the doors k
may be provided with openings or left open to admit air to the chamber h, which
air will mingle with the gases before they pass through the flues n to the fire
chamber or to the ash pit or air inlet chamber below the grate.
Figure 4 shows a modified arrangement of the invention applied to a boiler
having Galloway tubes. The chamber or drum h may be moved from the centre
with crank handles p' at the furnace front (indicated by dotted lines) or in any
convenient manner. Instead of a high bridge wall I prefer to use one the height
of two fire bricks and a slope from it to the rear end of the boiler as shown at
Figure 3.
Another leading feature of the invention is that the fuel may be introduced from
the fuel chambers into the fire chamber without establishing communication
between the fire chamber and the external air.
The furnace is hereinshown as provided with two fuel chambers, one at each side,
but it is obvious that it might have but one, if that were of sufficient capacity
to supply the fuel needed for the furnace.
It is not essential that the gases driven off from the fuel in the ovens should be
led to the fire chamber through the ash pit, as they might be introduced to the fire
chamber at some other point; but the said gases will be exposed to a fire in a
state of complete incandescence and will be introduced to the said fire in connection
with sufficient air to insure. the perfect combustion of the said gases.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what
I claim is
1. In a furnace provided with a fire-chamber for burning solid fuel, a rotary
fuel-chamber, oven, or retort exposed to the fire, and a flue leading from the said.
fuel-chamber to the fire chamber, the fuel chamber normally communicating with
the fire chamber only through the said flue substantially as described.
2. In a furnace provided with a fire chamber, a fuel chamber, oven or retort
capable of rotation upon a longitudinal axis, normally without direct communica-
tion with the fire chamber, and, having an opening or door to receive fuel from the
outside of the furnace, combined with a flue leading from the said fuel chamber to
the fire chamber, and means for discharging fuel from the fuel chamber into the
fire chamber substantially as described.
The 94th day of Santambor 190¢