Improvements in and connected with Apparatus for Burning Fine Fuel.
Year: 1895

page_text: Date of Application, 10th Dec., 1895-Accepted, 15th Feb., 1896
COMPLETE SPECIFICATION.
Improvements in and connected with Apparatus for Burning
Fine Fuel.
We, WILLIAM MELVIN RUSSELL, of 2310 7th Avenue, Merchant, ROBERT
ELLISON LESTER, of 1763 Madison Avenue, Merchant, and WILLIAM MORRIS
ERNST, of 422 West 22nd Street, Merchant, all of New York City, County and
State of New York, United States of America, 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:-
This invention relates more particularly to means for burning pulverized fuel,
such as fine coal and coal dust, and it has for its object to reduce the fuel to as
finely divided a state as possible, while at the same time mixing such fine fuel
with a proper quantity of air, and then delivering such mixture of fuel and air
into a combustion chamber where said fuel and air mixture are ignited. To carry
out the invention there is provided a novel pulverizer for dividing fuel into a fine
condition, the operative parts of the pulverizer being so arranged as to draw in the
proper amount of air to mix it with the fuel being pulverized, the said operative.
parts of the pulverizer at the same time acting to force the mixture of fine fuel
and air into a combustion chamber. This pulverizer embraces a casing and a series
of rotative blades or bats within it, so arranged as to toss the fuel about within the
casing and to gradually pass the fuel along from the in-take end to the outlet,
the fuel meanwhile being in a state of suspension within the casing and gradually
becoming finer as it passes along from one set of blades to another.
The invention further embraces a novel construction of nozzle or outlet for the
mixture of fuel and air, said nozzle being so arranged as to spread the outgoing
fuel into a thin sheet or film. This nozzle is provided with novel means for
increasing and diminishing the size of its outlet or opening so as to regulate the
amount of fuel being fed in accordance with the desired amount of heat to be
produced.
The invention is shown as applied to a stationary boiler, wherein the nozzle
opens into the combustion chamber beneath the boiler, means being provided to supply
said chamber with the requisite amount of fresh air to support combustion through
the length of the chamber. In the brick-work of the boiler setting there is also
shown a heating chamber which serves to supply heated air to the pulverizer above
mentioned.
The invertion further consists in the novel details of improvement and the
combinations of parts that will be more fully hereinafter set forth and then pointed
out in the claims.
Reference is to be had to the accompanying drawings forming part hereof,
wherein,
Figure 1 is a central longitudinal section of a boiler setting, showing our improved
appliances for supplying fuel to the combustion chamber;
Figure 2 is a cross section on the line 2, 2, in Figure 1 ;
Figure 3 is a horizontal section of the pulverizer and mixer;
Figure 3 is a detail sectional plan view;
Figure 4 is a plan view of the nozzle for passing the fuel into the combustion
chamber;
Figure 5 is a longitudinal section on the line 5, 5, in Figure 4 ;

page_text: Figure 6 is an end view of the nozzle looking from the left in Figure 4, and
showing-means for regulating the size of the delivery end of said nozzle; and
Figure 7 is an end view of the nozzle looking from the right in Figure 4,
showing the outlet thereof.
In the accompanying drawings, in which similar numerals of reference indicate
corresponding parts in the several views, I indicates a boiler, which may be of
suitable or well known construction, and 2 is a boiler setting or brick-work enclosing
the same, which may also be suitably constructed. 3 is a combustion chamber
beneath the boiler, and having a vertical space 3*, at the back thereof, leading
to the flues of the boiler. 4 is a suitable bridge adapted to assist in supporting the
boiler, and 5 is a suitable support at the forward part of the boiler, arranged to
form a space 6, for the passage of the heated products of combustion from the
flues of the boiler, the space 6 being entirely separated from the combustion
chamber 3. The arrangement for this purpose can be changed from that shown
in any desired or suitable manner. The combustion chamber 3 is kept closed
during operation, and in order to supply the requisite quantity of air thereto to
properly support combustion pipes 7 are shown which extend longitudinally of
said chamber at its lower part, and on opposite sides, as in Figure 2, these pipes 7
leading from the back of the brick-work 2, where they are supplied with fresh
air. The pipes 7 have a series of apertures 7", through which air is delivered into
the combustion chamber 3, and said pipes are shown as partially buried in the
brick-work surrounding the combustion chamber, so as to keep them from being
injured by the heat within the combustion chamber. These apertures 7 preferably
extend the major portion of the length of the combustion chamber 3, from its
forward end backwardly. Suitable means may be provided at the forward end of
the combustion chamber to permit access thereto, as by a suitably closed door 3b,
as shown in dotted lines in Figure 1.
The combustion chamber 3 will be supplied with fuel in a finely divided state at
its forward end, through a suitable nozzle 8, which will be placed in the front wall
of the brick-work 2. This nozzle 8 is shown more clearly in Figures 5 and 7, and
presents a narrow elongated opening to the interior of the combustion chamber.
The construction of the nozzle 8 is as follows:-
9, 9, are horizontally arranged plates having inwardly extending webs 10, the
edges of which are placed together so as to form a space between the plates 9, 9,
as shown in Figure 5. These webs 10, 10, diverge outwardly as shown in Figure 4,
and at the inner ends of said webs the plates 9, have end-pieces 11, which meet
on their edges, as shown in Figure 6, an aperture 12 being formed between the
end pieces 11 for the entrance of fuel into the nozzle. The plates 9 are fastened
together as by bolts or screws 13. The space between the plates 9 is narrow and
wide, the wider end being the delivery end for the fuel, from which the fuel when
blown from the nozzle, will be delivered in a thin wide sheet or film, which
gradually spreads outwardly before it passes from the nozzle, in accordance with
the divergence of the walls or webs 10, forming the sides of the nozzle. In order
to decrease or increase the size of the outlet-opening of the nozzle on a line
passing through the centre of the nozzle, while at the same time preventing an
obstruction from being formed within the nozzle, we place within said nozzle two
plates 14, 14, which are oppositely disposed, one plate being pivotally carried by
the corresponding plate 9, as shown in Figure 5. For this purpose the plates 9
are recessed, forming a shoulder 9, extending across them to receive the inner
ends of the plates 14, the edges of the plates 14 diverging to correspond with the
divergence of the webs 10 (see Figure 4). Suitable means may be provided for
pivoting the plates 14 within the space bounded by the plates 9, 9, and webs 10, 10,
and for this purpose screws 15 are shown as entering pivotal sockets 16 in the
edges of the plates 14, (see Figure 4) the screws being close to the shoulders 9.
The shoulders 9" are preferably curved at 9, to meet the correspondingly curved
ends 14 of the plates 14, so as to sustain a tight joint at that part, the inner
portion of the plates 9 and the plates 14 thereby constituting a substantially

page_text: continuous wall for the passage of the fuel through the nozzle, and when said
plates 14 are turned on their pivots their forward ends will approach or separate
to decrease or increase the width of the opening at the end of the nozzle, the
delivery opening for the fuel thereby being formed by the plates 14. At the
forward ends the plates 14 have flanges or lips 17, which cover the ends of
the plates 9, (see Figure 5).
Any suitable means may be employed for moving the plates 14 toward and from
each other. Convenient means are shown for this purpose consisting of shafts 18
passing along the plates 9 and suitably journaled thereon, as by brackets 19, at
their forward ends, the inner ends of the shafts 18 being journaled in the end
pieces 11. On the shafts 18 are cranks 20, to which are pivoted links 21, which
pass through openings 22 in the plates 9, and are pivoted to the outer faces of the
plates 14, as by brackets 23, carried by said plates 14. By this means as the
shafts 18 are rocked, the plates 14 will be moved inwardly and outwardly. At
the outer ends of the shafts 18, contiguous to the inlet opening 12 of the nozzle
are crank armis 24, by which the shafts 18 can be operated. By preference the two
shafts 18 are operated simultaneously so that the plates 14 will be moved toward
each other simultaneously and likewise-separated at the same time, as the case may
be, to keep the centre of delivery on a horizontal line. Suitable means may be
provided for thus operating the crank arms 24 together for the purpose stated.
26 is a lever or arm shown centrally pivoted and having a suitable handle 27 by
which it can be turned, the lever 26 being pivoted at its opposite ends to links 28,
which are also pivoted to the crank-arins 24 (see Figure 6), whereby, as the
lever 26 is turned in one direction the shafts 18 will be rotated to move the
plates 14 together to reduce the size of the outlet of the nozzle and when the lever 26
is turned in the opposite direction the motion of the plates 14 will be reversed so as
to increase the size of the nozzle outlet. The nozzle 8, thus constructed will be
located within the brick-work 2 around the furnace in line with the forward end of
the combustion chamber and the crank arms 24 will project through the forward
face of the wall of the brick work.
The nozzle 8 constructed and supported as above specified, is connected at its.
opening 12 with a pipe 30 which leads. to a pulverizer and blower 31, which is
adapted to receive the fuel in a coarse state, then pulverize and mix it with air
and deliver said mixture, under pressure, to the nozzle 8, from which it passes
into the combustion chamber 3 (see Figure 1). The pulverizer and blower is.
ai ranged as follows:-
32 is a casing, preferably cylindrical, having a hinged top 32", to permit access.
to the interior, the casing being supported by legs 33, or in any suitable manner.
The pipe 30 enters the casing 32 on its lower side at the forward or delivery end..
The opposite end of this casing 32 is connected with a hopper or spout 34, which
receives fuel from a suitable receptacle 35 and chute 36.
At the in-take end of
the casing 32 is an opening 37 for the entrance of air. The opening 37 is shown
connected by a pipe 38, with a hot-air chamber 39, in the brick-work 2 of the
boiler setting. The chamber 39 is shown located beneath the combustion.
chamber 3, so that the bricks that are heated by the fuel in said combustion
chamber will heat air in the chamber 39 to supply hot air to the pulverizer and
blower 31. The chamber 39 has an air inlet 40, shown in the form of a pipe
leading to the outer air, and provided with a suitable valve to permit air to enter
the chamber 39, and to prevent it from escaping therefrom through the pipe 40.
Within the casing 32 is a horizontal shaft 42 carried in suitable bearings and
having a pulley 43 by which it can be rotated by a belt from a suitable source.
Rigidly mounted upon the shaft 42 are a series of arms 44, 45. The arms 44
extend ontwardly nearly to the casing 32, while the arms 45 are shorter and are
located between the arms 44, all as in Figure 3. The arms 44, 45, are shown
carried by hubs or sleeves 46, 47, mounted on the shaft 42, and secured thereto by
screws, splines or other desired holding means. On the outer ends of the
arms 44, 45 are blades or bats 48, 49, which consist of flat plates suitably secured:

page_text: to said arms. The plates or blades 48, 49, are shown in rectangular form, and th
inner edges are placed at an angle to the shaft 42, so that they diverge outwardly
from a line parallel with the shaft 42 from the back or inlet end A of the casing 32
toward the delivery or front end B of said casing. The angles of divergence of
the blades or bats 48 are different, ranging from the back A to the front B of the
casing, that is to say, the angles of the blades gradually increasing, as shown in
Figure 3. The angles of divergence of the inner blades or bats 49 are the reverse
of the angles of the blades or bats 48, that is to say, they diverge outwardly from
the front B to the back A of the casing relatively to the shaft 42. The arms 44, 45,
and blades or bats 48, 49, are arranged in series radially around the shaft 42, there
being, for instance, six of said arms and blades in each series, and said arms and
blades or bats rotate together or in the same direction, and on account of their
peculiar inclinations they act to draw in air from the back A of the casing, and
to propel it forward through the casing and out of the front B thereof, with
considerable force or pressure, causing it to pass out through the pipe 30.
The operation of the pulverizer and blower is as follows:-The shaft 42 is
rotated and the fuel is fed into the casing 32, the fuel preferably consisting of fine
coal or dust. The fuel is met by the first series of blades 48 and is struck a sharp
blow by them, which tosses it against the next series of blades or bats 49, which
act to drive part of the fuel back against the blades 48, which again toss the fuel
forward. As a circulation of air is induced by the rotating blades or bats from the
back A toward the front B of the casing, the fuel will be gradually carried forward,
the air currents from the blades 48 being stronger than those from the blades 49.
The second series of blades 48 also act to toss the fuel forward, the corresponding
series of blades 49 tossing some of it backwards, and so on as the blades encounter
the fuel, gradually carrying it toward the front B of the casing, the blades 49
particularly serving to strike the larger particles of fuel as they drop inwardly to
drive them back against the blades 48. This continued tossing of the fuel from one
blade or bat to and against the next gradually pulverizes the fuel until it issues
from the casing in a finely divided state, the attrition of the blades on the fuel, as
well as one particle of fuel against another, serving to crush or divide it. The
cross currents of air within the casing also serve to toss the fuel back and forth
with such rapidity as to thoroughly disintegrate it. The farther the fuel passes
from the back A to the front B of the casing, the finer it becomes, and therefore
the more readily the current of air in the casing can carry the fuel along to deliver
it. The whirling of the fuel within the casing and the current of air passing there-
through together with the moving blades cause the fuel to remain in suspension so
that it will at all times be in a position to be struck by the blades or bats as well as
to grind one particle against another. On account of the outward and forward
divergence of the blades or bats 48 the lighter fuel is continually thrown forward
until when it reaches the front of the casing it is forced through the pipe 30, or the
outlet, and this will not occur until it is in the desired finely divided state. This
whirling of the fuel also intimately mixes it with the air in the casing, so that
when it passes through the pipe or outlet 30 it is properly mixed with the air to
permit of its ready ignition in the combustion chamber 3. The increasing angles of
the blades or bats 48 also act to create a strong outward current of air at the
delivery end of the casing so that by the time the fuel reaches the outlet end of the
casing the last series of blades create such a current of air as will force the mixture
of air and fuel from the casing. Thus the blades or bats serve the several purposes
of pulverizing the fuel, mixing it with air and forcing it from the casing when it
has arrived at the proper degree of fineness, for until then the fuel is held in
suspension and whirled around in the casing so that if it is not in the proper
condition for ready and quick ignition it will not be delivered from the casing. By
this means the proper pulverization of the fuel is assured whereby complete
combustion can be effected.
If desired the blades or bats 49 could be omitted and only the blades or bats 48
used. On the inner surface of the casing are also, by preference, placed ribs 50.

page_text: against which the fuel can strike as it is propelled through the casing, but these
ribs do not form chambers in which the blades rotate as they are outside of the
ends of said blades.
The complete operation is as follows:-
If the boiler 1 is used to supply steam for rotating the shaft 42, and there is no
steam in the boiler, a suitable fire can be made in the chamber 3 until the
requisite amount of steam is produced, or the shaft 42 can be temporarily rotated
by any suitable means to supply the pulverized fuel to the combustion chamber
until the required amount of steam is generated to keep said shaft rotating. But if
there is steam left in the boiler it can be used to rotate the shaft 42.
In either case-
the required amount of fuel is fed from the receptacle 35 to the pulverizer and
blower 32, the rotating blades or bats of which pulverize the fuel as before
explained. These rotating blades also act to draw hot air from the air chamber 39.
into the casing 32 and to thoroughly mix it with the fuel being pulverized. The
rotating blades thereupon blow or force the mixture of air and fuel into and
through the nozzle 8, and thence into the combustion chamber 3, where it is.
ignited. (To first ignite the fuel in said chamber, a small wood fire can be kindled
therein.) The mixture of air and fuel thus passing into the chamber 3, under.
pressure, and issuing through the narrow elongated outlet of the nozzle, spreads
out in the combustion chamber in a long thin film or sheet, and the particles of fuel
mixing with the air in the chamber 3 quickly ignite and burn with an intense heat..
By forcing the mixture of fuel and air into the combustion chamber under sufficient
pressure, it will be carried back on a horizontal plane, the full length of the boiler,.
the flame, in fact, passing up into the space 3 at the back of the boiler and
entering the flues thereof. As heated air is delivered into the combustion.
chamber 3 with the fuel, and as other heated air is delivered to said chamber by
the pipe 7 (when the latter is used) quick and perfect combustion of the fuel is
caused and about all the combustible portions of the fuel and air are instantly
ignited and burned. The mixture of pulverized fuel and air burns like a gas
flame, creating an intense heat. The proper proportion of air and fuel to be
mixed is regulated as the rotation of the blades 48, 49, propels an amount of air
and fuel commensurate with their rate of rotation and with the feeding of the fuel..
A suitable device may be provided to cause the right amount of fuel to be fed to
the pulverizer in accordance with the rate of rotation of the blades, so that if a
small amount of heat is desired, the blades can rotate at the proper speed and be
supplied with less fuel and thus propel the proper quantity of air with the fuel, and
if great heat is required the blades can be rotated faster and thereby secure more.
fuel and propel more air. By this means the amount of steam to be produced
can be easily regulated by the rotation of the blades of the pulverizer and
blower.
Also, when a small quantity of fuel is fed the outlet of the nozzle is reduced in
size by adjusting the plates 14, 14, toward each other, and as it is desired to
increase the heat the height of said opening is increased, by which means the
thickness of the sheet or film of fuel passed into the chamber 3 is regulated in
accordance with the amount of fuel passing. By this means also proper combustion
of the fuel is regulated because the thickness of the film of fuel is regulated in
accordance with the heat to be produced and the ability of all particles of fuel to
be consumed that may be issuing from the nozzle. If the outlet of the nozzle were-
always of one size it would occur that if a small quantity of fuel were issuing it
would not be projected with sufficient force to properly spread it into a sheet or
film of the proper dimensions to quickly cause ignition and thereby part of the fuel
would be wasted. Our improved nozzle is therefore of importance in regulating
the conditions of the sheet of issuing fuel, and is specially useful in connection with
the improved pulverizer and blower, which has the three functions of pulverizing the
fuel, mixing it with air and forcing it from the nozzle so that as the delivery of fuel
from the casing 32 is regulated by the rate of rotation of the blades, the size of the-

page_text: reginated by the size of the outlet
thereof.
It will be understood that the outlet of the nozzle will remain on a line drawn
through its centre by moving both plates 14, 14, toward and from each other equally
and together. By this means the fuel will issue on a horizontal plane at all times,
and not be directed upwardly against the boiler or downwardly against the bottom
of the combustion chamber.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be, performed, we declare that what
we claim is:
1. The combination of a pulverizer and a pipe leading thereto from an air heating
chamber, means to deliver fuel to said pulverizer to cause said fuel to be pulverized
by the mechanism of said pulverizer, said mechanism being arranged to mix said fuel
with air while pulverizing it and to force said mixture from said pulverizer, and
means for delivering said mixture of hot air and pulverized fuel together to a
combustion chamber, substantially as set forth.
2. The combination of a casing, an inlet at one end for conducting air into said
casing, a pipe or hopper leading into said casing at the same end as the inlet to
deliver fuel thereto, mechanism within said casing arranged to pulverize fuel while
at the same time mixing it with the air entering said casing, the said devices which
pulverize the fuel being arranged to create a current of air to force the fuel from
the entering end of the casing out through the opposite end thereof, and means for
conducting the mixture of air and fuel from said casing to a combustion chamber,
substantially as described.
3. The combination of a boiler and a setting therefor, having a combustion
chamber for said boiler and a hot air chamber within said setting beneath said
combustion chamber, and an inlet for air into said hot air chamber whereby air will
be heated by radiation from said setting, with a combined pulverizer and blower
having one end connected with said hot air chamber by a suitable pipe the opposite
end being connected by a suitable pipe with said combustion chamber, said
pulverizer and blower containing blades or bats which are arranged to pulverize
fuel and mix it with hot air from said hot air chamber, the said blades which
pulverize the fuel being arranged to create a current of air within said pulverizer
to force the said mixture of fuel and hot air into said combustion chamber,
substantially as described.
4. The combination of a boiler and a setting therefor having a combustion
chamber, a hot air chamber within said setting and means to permit entrance of
air into said hot air chamber, and to prevent its exit through said entrance, with
means for pulverizing and blowing fuel into said combustion chamber, and a
leading from said hot air chamber to conduct hot air to the means for blowing the
pipe
fuel into said combustion chamber, substantially as described.
5. The combination of a boiler and a combustion chamber therefor, with a
nozzle opening into said combustion chamber, said nozzle having means. for
contracting and enlarging its outlet in equal degrees from a normally central line
through said nozzle, meaus for holding the delivery end of the nozzle in any
position to which it may be adjusted, means for supplying pulverized fuel to said
nozzle and for forcing it from said nozzle into said combustion chamber,
substantially as described.
6. A nozzle consisting of a hollow casing having outwardly diverging walls and
means for contracting and expanding the delivery end of said nozzle equally on
a line passing centrally through said nozzle, whereby a sheet or film of fuel can be
forced through said nozzle on a horizontal plane so as to spread out laterally after
leaving the nozzle, substantially as described.
7. A nozzle consisting of a hollow casing having outwardly diverging side walls
and two plates within said casing having correspondingly diverging edges, and

page_text: means for moving the outer ends of said plates toward and from each other, so
that fuel passing from the nozzle can be delivered in a sheet or film which spreads.
out laterally as it issues from the nozzle, substantially as described.
8. A nozzle consisting of a hollow casing having oppositely disposed shoulders 9b
and two plates respectively abutting against said shoulders to afford a smooth
surface within said casing, and means for moving the outer ends of said plates
toward and from each other at the delivery end of the nozzle, substantially as
described.
9. A nozzle consisting of two plates, side walls or webs adapted to be brought
together on their edges to form a space within said nozzle, rear walls carried by
said plates adapted to close the back of said nozzle, said walls forming an inlet
opening, and two plates carried within said first-mentioned plates and means for
moving said plates equally toward and from each other at their outer ends,
substantially as
described.
10. A nozzle consisting of two plates and means for holding them at a distance
apart to form a space between them, two plates pivotally carried within the space
formed by said first mentioned plates, rock shafts journaled on the first mentioned
plates and having cranks and links connected, with the movable plates for operating
the latter, and means for rocking said shafts to move the inner plates toward and
from each other, substantially as described.
11. A nozzle consisting of two plates and means for holding them at a distance
apart to form a space between them, two plates pivotally carried within the space
formed by said first mentioned plates, rock shafts journaled on the first mentioned
plates and having cranks and links connected with the movable plates for
operating the latter said rock shafts having crank arms 24 and means connected
with said crank arms for moving them conjointly so as to move the outer ends of
said movable plates toward and from each other equally and simultaneously to
contract and increase the distance between the outer ends of said movable plates
equally, substantially as described.
12. A nozzle consisting of two plates 9, webs 10, 10, carried by said plates and
adapted to register on their edges whereby a space is formed between said plates
and webs, means for clamping said plates together, walls at one end of said plates
forming an inlet opening two plates 14 within said nozzle and respectively pivotally
connected at their inner ends with said plates 9, and means for rocking said
plates 14 on their pivots to move their outer ends toward and from each other,
substantially as described.
13. A nozzle consisting of a hollow casing and plates 14 therein, said plates 14
having pivots at their inner ends so arranged that said plates when turned on their
pivots will always present a smooth inner surface within the nozzle casing while
their outer ends move toward and from each other, substantially as described.
14. A pulverizer consisting of a casing, a shaft therein, and blades or bats
carried by said shaft and placed at angles laterally to the axis of said shaft, the
angles of said blades or bats gradually increasing from one end of the shaft toward
the other, and other blades or bats carried by said shaft and placed at reverse
angles to said first mentioned blades or bats, substantially as described.
15. A pulverizer consisting of a casing and a shaft therein, and blades or bats
carried by said shaft, and placed at gradually increasing angles relatively to the
axis of said shaft, the angles of said blades or bats increasing from the inlet end
of said casing to its outlet, combined with a series of annular ribs within the cusing
the inner surfaces of said ribs lying outside of the outer edges of the blades to
1orm a space between the ribs and blades for the passage of material, said ribs
acting to retard the flow of the material, substantially as described.
16. A pulverizer consisting of a casing having a rotative shaft and two sets of
blades or bats carried thereby, one set of said blades or bats being placed at
angles to the longitudinal axis of said shaft, the angles of divergence of said blades
or bats gradually increasing from one end of the shaft to the other, the other set
of blades or bats being placed at angles to the longitudinal axis of said shaft

page_text: and on the opposite side thereof, the angles of divergence of said blades or bats
gradually increasing from one end of the shaft to the other, substantially as
<described.
Dated this 10th day of December 1895.
ALLISON BROS.,
Agents for the Applicants.