Improved Method and Apparatus for Burning Culm or Pulverised Coal
Year: 1889

page_text: Date of Application, 2nd July, 1889
Complete Specification Left, 29th Apr., 1890-Accepted, 31st May, 1890
PROVISIONAL SPECIFICATION.
Improved Method and Apparatus for Burning Culm or
Pulverised Coal.
A communication from abroad by ALLAN MASON, of Brooklyn, in the County of
Kings and State of New York, United States of America.
I, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both in
the County of Lancaster, and 323, High Holborn in the County of Middlesex
Civil Engineer, do hereby declare the nature of this invention to be as follows:-
The improved process of burning pulverised coal consists in a method of introducing
and supplying the same which enables the more effectual maintaining of the particles
in suspension and general distribution throughout the combustion chamber together
with the air for effecting the combustion so that the mixture and union of atoms is in
process of operation among and throughout the moving particles in all the space and
in far greater amount and intensity than as commonly injected into the furnace or as
burned in a mass or bed on the grate, with correspondingly more perfect and effectual
combustion and greater production and intensity of heat in a given space.
Whilst
it is proposed to use any approved efficient means of maintaining the suspension of the
atoms of coal a sufficient length of time to effect the mixture and union of atoms
which results in combustion while in suspension, as by showering the same from
the upper portion of the chamber slowly downward into or along with the air for
combustion, the means which it is preferable to use consist of air jets or blasts
introduced in such manner as to produce currents, counter currents, eddies and
cycles, calculated to bear up and distribute the coal till consumed, the coal being
preferably introduced along with and by said jets, but may be otherwise introduced
if preferred. The improved apparatus for burning culm pulverised coal, etcetera,
consists of contrivances for maintaining the particles in suspension and general
distribution throughout the combustion chamber together with the air for effecting
the combustion, so that the mixture and union of atoms is in process of operation
among and throughout the moving particles in all the space.
The apparatus is applied to the furnace of an ordinary return flue boiler (or other
furnace) having a combustion chamber provided with a fire door and with a flue back
of the bridge wall in the usual manner. In such furnace a pan shaped deflector is
provided in proximity to and below the fire door and similar deflectors in or about
the crown of the furnace one facing the bridge wall and the other the fire door or
other suitable arrangement. An air injector is applied to the furnace (at the rear
wall preferably) so that the air blown into the furnace shall be directed against the
pan shaped deflector. Between the air supply and the nozzle of the injector a device
is applied to feed coal dust to the air spout, say by a screw feeder, for example, or
other suitable means, so that the coal dust will be carried along by the air mixed
therewith and injected into the furnace and held in suspension for combustion in the
fire chamber. The blast coal dust laden air first impinges on the pan-shaped
deflector spreading more or less but leaving a comparatively still air space below
for the reception of the ashes, then it is turned up violently by the said deflector
diffusing itself in the upper spaces of the fire chamber where it is held in cycles or
whirls by the incoming jet below repeatedly coming in contact with the deflectors in
the crown of the furnace which turn it backward and downward into the incoming
blast which takes along with it any yet unconsumed particles and prevents them from
alling into the ash pit unconsumed.

page_text: The same process may be applied to the combustion chamber of a locomotive boiler
fire box. The injecting nozzle in this case entering near each side from under
the grate and being upwardly curved to form deflectors for projecting the coal dust
and air upward into opposite upper angles, and thereby deflected so as to meet over
the centre of the chamber and produce gyrating cycles, whirls, etcetera, by their
counter action and maintaining the suspension of the particles or atoms of coal until
consumed.
To begin with fire may be started in the coal grate to produce the heat necessary
for igniting the coal dust or a torch may be introduced through the fire door. For
the subsequent continuation of the fire the high temperature within the chamber is to
be depended on.
A further application of the invention consists in injecting the pulverised coal with
air as above described and for a time suspending it in the chamber by the force of the
air blast combined with the action of the deflectors and at the same time burning
lump coal or other similar fuel below the injected finely divided fuel in independent
separate burner below which the coal ashes are precipitated, the latter being used
mainly for the purpose of starting the fire and to insure the continuous burning of
the finely divided fuel by reigniting it in case of temporary extinguishment to which
it is liable from various causes.
The furnace is constructed the same as that first described herein and the operation
of injecting the fuel and causing it to circle over in the fire chamber until complete
combustion is obtained is the same as described, in connection with said furnace.
But as a modification of the above instead of using the deflectors with the blast of
coal dust projected laterally a series of injectors may be distributed in the area of the
furnace chamber and adapted for projecting the fuel laden blast upwardly and directly
against the crown sheet or against the boiler as the case may be.
Together with these contrivances for burning the finely divided fuel an auxiliary
fire of lump coal or similar fuel may also be used, in the lower part of the fire chamber.
For this purpose it is preferable to employ sectional trough shaped burners arranged
in the fire box like ordinary grate bars with wide spaces between them through which
the ashes from the combustion of the injected fuel fall into the ash pit. As the fire
on the ordinary grate bars would be clogged by the falling ashes, the burners are
made of such limited transverse area that the ascending heat currents from them will
turn away into the ash pit such matters resulting from the combustion of the finer
fuel, as might tend to fall into them from the combustion above, and thus be self
protected against the dust and ashes from the upper fire. These trough shaped
burners may be adapted to slide in and out of the furnace through suitable
openings in one side wall so that the fuel may be introduced with the said
burners. The troughs should be perforated for the supply of air to support
combustion and for the escapeof the ashes and dust resulting therefrom. The upper
edges of the troughs are flanged outwardly to furnish bearings for the slide ways and
also for a useful effect in distributing the air in jets through the perforations in said
flanges, for admixture with the gases and vapours of combustion. The burners can
be separately withdrawn for replenishing with fuel, without interrupting the burning
of the fine fuel, care being taken to avoid withdrawing them entirely from the
openings, so that the part remaining in the opening practically closes the same. In
this arrangement of the burner a number of injectors for air and pulverised fuel may
be used and passed up through the ash pit and between the trough shaped burners
and arranged to inject the air and fuel angularly with respect to each other and to
the burners.
Dih:
T.1
1000
WM. P. THOMPSON & Co.,
Agents for the Applicant,

page_text: Improved Method and Apparatus for Burning Culm or
Pulverised Coal.
A communication from abroad by ALLAN MASON, of Brooklyn, in the County of Kings
and State of New York, United States of America.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign Patent
Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both in the
County of Lancaster, and 323, High Holborn, in the County of Middlesex, Civil
Engineer, 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:-
The improved method of burning pulverised coal consists of a method of
introducing and supplying the same, which enables more effectually maintaining
the particles in suspension and general distribution throughout the combustion
chamber together with the air for effecting the combustion, so that the mixture
and union of atoms is in process of operation among and throughout the moving
particles in all the space and in far greater amount and intensity than commonly
injected into the furnace or as burned in a mass or bed on the grate, with correspond-
ingly more effective or perfect combustion and greater production and intensity
of heat in a given space. While it is proposed to make use of any approved efficient
means of maintaining the suspension of the atoms of coal a sufficient length of time
to effect the mixture and union of atoms which results in combustion while in
suspension, as by the showering of the same from the upper portion of the chamber
slowly downward into or along with the air for combustion, the means which are
represented in this example consist of air jets or blasts, introduced in such manner as
to produce currents, counter-currents, eddies, and cycles calculated to bear up and
distribute the coal till consumed, the coal being preferably introduced along with and
by said jets, but may be otherwise introduced, if preferred, all as hereinafter
described, reference being made to the accompanying drawings, in which several
forms of jet apparatus are represented for the purpose, and also means for maintaining
an auxiliary fire of coal in the lower part of the combustion-chamber.
The improved apparatus for burning culm, pulverised coal, etcetera, consists of
contrivances for maintaining the particles in suspension and general distribution
throughout the combustion chamber, together with the air for effecting the combustion,
so that the mixture and union of atoms is in process of operation among and
throughout the moving particles in all the space and in far greater amount and
intensity than as burned in a mass or bed on the grate, with correspondingly more
effective or perfect combustion and greater production and intensity of heat in a
given space.
In the drawings:
Figure 1 is a longitudinal sectional elevation of a boiler-furnace showing one
contrivance of apparatus that may be employed for maintaining the suspension and
distribution by the cycling currents produced in the furnace by an injecting blast of
air laden with atoms of coal.
Figure 2 is a transverse section of a locomotive-boiler furnace with a modified
arrangement of the injecting apparatus adapted for that kind of furnace.
In Figure 1 a represents an ordinary return-flue boiler; the combustion chamber
of the furnace, e the fire-grate, d the fire-door, e the ash-pit door, and the flue back
of the bridge-wall g. In such a furnace deflectors hij are provided of refractory
material, as shown, or in any approved arrangement, with an injector k for air to be
forced in, preferably, at the back of the chamber by a fan or other means, and coal-
dust charged into the air-spout by a screw-feeder m or other means, to be carried
along for feeding the furnace and for being mixed and combined with the air and
held in suspension for combustion by it.

page_text: '
It will be seen that the blast first traverses the chamber a little above the grate,
spreading more or less, but leaving a comparatively still air-space below for reception
of the ashes. Then it is turned upward violently by the deflector h, and, coming in
contact with deflector i, is then projected forward against j, which turns it downward
into the incoming blast, which takes along with it any yet unconsumed particles and
prevents them from falling on the grate or into the ash-pit.
It will also be seen that these appliances may be readily fitted to a common boiler-
furnace already in use without material expense of fitting, and may be as readily
removed.
For adaptation of the same invention to the combustion-chamber b of a locomotive-
boiler fire-box n the injecting-nozzle may have branches entering near each
side from below the grate and being suitably upwardly curved to constitute
deflectors for projecting the coal upward into the opposite, upper angles, and be
thereby deflected, so as to meet over the centre of the chamber, and produce gyrating
cycles by their counter action adapted to maintain the suspension of the coal atoms
until consumed. To begin with, fire may be started on the coal-grate to produce the
heat necessary for igniting the coal-dust, or a torch may be introduced through the
fire-door.
For the subsequent continuance of the fire, the high temperature within the
chamber is to be depended on for re-igniting the fine particles of coal in case of
any temporary suspension due to irregularity in the feeding of the coal; but it is
intended that the coal shall be so fine and shall feed with such regularity that when
properly adjusted no interruption will occur.
By this method all the combustible matters in the coal will be effectually consumed
with greater economy of fuel, and an especial advantage is gained in the total pre-
vention of clinker and slag. What ash is developed may fall in part into the
ash-pit through some localities where the eddies favour it, while some may be carried
over the bridge-wall and descend where the cycles have less suspending effect.
Together with the fire of coal atoms thus maintained throughout the chamber
generally it will be desirable to maintain an auxiliary fire of lump coal in the
lower portion of the furnace at or about the locality of the ordinary fire-bed,
mainly for the purpose of renewing the fire of coal-dust in cases of interruption, to
which it is liable by irregularity or clogging of the fuel and other causes, but also for
adding to the capacity of the furnace for useful effect. As an ordinary coal fire or
other fire of uniform spread over the area of the chamber would fail of this purpose
because it would soon be clogged with ashes from the fire above, sectional burners p
are employed which are fully described hereinafter in connection with Figures4 to 7.
Figure 3 is a longitudinal sectional elevation of a boiler-furnace, showing another
contrivance of apparatus that may be employed for maintaining the suspension and
distribution by the cycling currents produced in the furnace by an injecting blast of
air laden with the atoms of coal.
In this Figure a represents an ordinary return-flue boiler; b the combustion-
chamber of the furnace, d the fire-door, f the flue back of the bridge-walls g.
In such a furnace a pan-shaped deflector is provided, and when required, others i j
of refractory material, as shown, or in any approved arrangement with an injector k
for air to be forced in, preferably, at the back of the chamber by a fan or other
means, and coal-dust charged into the air-spout by a screw feeder m, or other means
to be carried along for feeding the furnace and for being mixed and combined with
the air and held in suspension for combustion by it. It will be seen that the blast
first impinges on the pan h, located a little above the ash-pit spreading more or less,
but leaving a comparatively still air-space below for reception of the ashes. Then it
is turned upward violently by the deflector / diffusing in the upper space, where it is
held up in cycles by the incoming jet below, repeatedly coming in contact with
deflectors i and j, which turn it downward into the incoming blast, which takes along
with it any yet unconsumed particles and prevents them from falling onto pan or
over its edge into the ash-pit, said pan being narrower and shorter than the width and
length of the chamber. It will also be seen that these appliances may be readily

page_text: fitted to a common boiler furnace already in use without material expense of fitting
and may be readily removed..
A further application of the invention consists in ejecting the pulverised coal with
air as above described and for a time suspending it in the chamber by the force of the
air blast combined with the action of the deffectors and at the same time burning
lump coal or other similar fuel below the injected finely divided fuel in independent
separate burners below which the coal ashes are precipitated, the latter being used
mainly for the purpose of starting the fire and to insure the continuous burning of
the finely divided fuel by re-igniting it in case of temporary extinguishment to
which it is liable from various causes.
The apparatus for carrying out the above is illustrated in Figures 4 to 7, Figure 4
being a longitudinal section of a boiler furnace provided with apparatus for carrying
out the invention,
Figure 5 a transverse section of the same,
Figure 6 a perspective view of one of the burners for lump coal; and
Figure 7 a horizontal section of the furnace.
In Figure 4 a represents an ordinary turn-flue boiler, 6 the combustion-chamber of
the furnace, d the fire-door, e the ash-pit door, the bridge-wall, and g the flue back
of the bridge-wall. In such a furnace, or any other suitable therefor, deflecting-
surfaces hij are provided of refractory material, as shown, or in any approved
arrangement, with an injector & for air to be forced in, preferably at the back of the
chamber, by a fan 1, or other means, and coal-dust charged into the air-spout by a
screw feeder m, or other means, to be carried, along for feeding the furnace and for
being mixed and combined with the air and held in suspension for combustion by it.
It will be seen that the blast first impinges on the pan h, located a little above the
ash-pit, spreading more or less. Then it is turned upward violently by the deflecting-
surface h, diffusing in the upper space, where it is held up in cycles by the incoming
jet below, repeatedly coming in contact with deflecting-surfaces i and j, whereby it is
turned downward into the incoming blast, which takes along with it any yet uncon-
sumed particles, and prevents them from falling into the ash-pit, and retains them
in the vortex of combustion until consumed, the resulting smoke and gases of com-
bustion being at the same time urged along the flue g; but instead of using the
deflecting-surfaces with the blast of coal-dust projected laterally, a series of injectors k
may be distributed in the area of the furnace-chamber and adapted for projecting the
blasts upwardly from the lower space directly against the crown-sheet of the furnace
or fire-box, or against the boiler, as represented in Figure 7 with practically the same
effects in maintaining the suspension of the fine fuel during the period of combustion.
Together with such contrivances for the combustion of the fine fuel, means are also
provided for an auxiliary fire of lump-coal in the lower portion of the furnace
chamber at or about the locality of the ordinary fire-bed, mainly for the purpose of
starting the fire of coal-dust in the first place and of renewing the same from time
to time in cases of interruption, to which it is liable by irregularity or clogging of the
feed and other causes, but also for adding to the capacity of the furnace for useful
effect, for which means sectional burners p with wide spaces between them are
employed, through which the falling ashes from the upper fire may fall into the pit,
because an ordinary coal or other fire of uniform spread over the area of the chamber
would fail of this purpose by being clogged with ashes from the fire above, said
burners being of such limited transverse extent as that the ascending currents from
them will turn away into the pit such matters as might tend to fall into them, and
thus be self-protecting so far as the falling matter of the upper fire is concerned.
These burners p may consist of trough-shaped drawers adapted to slide in and out of
the furnace through suitable openings p₁ of the side wall of the furnace for receiving
and introducing the coal. The troughs will be perforated in the sides and bottom
for the supply of air for supporting the combustion of the coal in them and for the
escape of the ashes through the bottom. The upper edges of the troughs are flanged
over horizontally and outwardly at t for bearings in the slideways in the openings p²,

page_text: and also for a useful effect in distributing the air through perforations in jets from
below for admixture with the gases and vapors rising from the burners, said flanges
being suitably perforated for the purpose.
It will be noted that these burners can be withdrawn individually for replenishing
them with coal without interrupting the burning of the fine fuel, as would be the
case on opening the fire-door and replenishing the fire in the usual way, care being
taken not to draw them entirely out of the openings, so that the part remaining in
the opening constitutes a practicable closure thereto.
By this invention, all the combustible matters in the coal will be effectually con-
sumed with greater economy of fuel, and an especial advantage is gained in the total
prevention of clinker and slag. What ash is developed may fall in part into the
ash-pit through some localities where the eddies favour it, while some may be carried
over the bridge-wall and descend where the cycles have less suspending effect.
Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed, as communicated to me by my
foreign correspondent, I declare that what I claim is:-
1. The method of burning culm or fine coal which consists of injecting it into the
furnace-chamber and deflecting the injected stream backward over and into the
incoming jet or jets in continuous suspension during combustion over a still air
space in which the ashes collect separately from the burning coal and maintaining
therewith an igniting and renewing fire, substantially as described.
2. The method of burning culm or pulverised coal and lump coal in combination
by injecting the pulverised coal into and for a time maintaining it in suspension in
the furnace-chamber by the injecting forces and at the same time burning the lump
coal below the injected fine fuel in independent or separate burners between which
the coal-ashes are precipitated, substantially as described.
3. The combination, with a furnace-chamber, of one or more air and pulverised-
coal injectors and deflecting-surfaces for injecting and for a time maintaining the
coal in suspension in the furnace-chamber by the injecting forces, and independent
or separate burners below the injected fine fuel between which the coal-ashes are
precipitated, substantially as described.
4. The combination, with a furnace-chamber, of one or more air and pulverised-
coal injectors and deflecting surfaces for injecting and for a time maintaining the
coal in suspension in the furnace-chamber by the injecting forces, and independent or
separate burners below the injected fine fuel, between which the coal-ashes are
precipitated, and consisting of trough-shaped drawers adapted for being inserted
and withdrawn through the side wall of the furnace and being charged with fuel
independently, substantially as described.
5. The combination, with a furnace-chamber, of the improved burner consisting of
a fuel-holding trough having perforated sides and top flanges and fitted in a slideway
through the furnace-wall, substantially as described.
6. The combination, with a furnace-chamber, of an air and pulverised-coal injector
upwardly projecting the injected coal into the chambers provided with deflecting-
.surfaces, as shown, thereby maintaining the coal in suspension during combustion
above a still air-space in the lower part of the furnace-chamber for reception of the
ashes, substantially as described.
7. The combination, with a furnace-chamber, of an air and pulverised-coal injector
and deflectors in the chamber upwardly projecting and maintaining the coal in suspen-
.sion during combustion above a still air-space in the lower part of the furnace-chamber
for reception of the ashes, substantially as described.
8. The combination, with a furnace-chamber, of an air and pulverised coal injector
and a concave-pan deflector in the lower space, on which the impinging jet is diffused
upwardly and backward over the incoming jet, substantially as described.
9. The combination, with a furnace-chamber, of an air and pulverised-coal injector
that injects the coal and air, the deflector h, located above a comparatively still air-

page_text: space below for reception of the ashes, in the lower space whereon the incoming jet
impinges and one or more deflectors in the upper space that direct, diffuse, and, with
the current of injected air, maintain the coal in suspension during combustion, sub-
stantially as described.
acil
1900
WM. P. THOMPSON & Co.,
Agents for the Applicant.