Improved Process for Burning Coal and Hydrocarbon Fuel, and Apparatus therefor.
Year: 1889

page_text: Date of Application, 2nd July, 1889
Complete Specification Left, 29th Apr., 1890-Accepted, 31st May, 1890
PROVISIONAL SPECIFICATION.
Improved Process for Burning Coal and Hydrocarbon Fuel, and
Apparatus therefor.
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, & 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 coal and hydrocarbon fuel in combination, consists
in burning the oil or oil vapours or gas in one or more suitable burners, located in the
furnace chamber, somewhat higher than the ash pit, with ample surrounding space
for the ashes to descend into the pit without clogging these burners, and at the same
time maintaining a fire of coal or similar fuel around and above the oil or vapour
burner or burners, with pulverised coal atoms in suspension and general distribution
throughout the chamber together with the requisite amount of air for the support of
combustion, so that the mixture and union of atoms are in process of operation
among and throughout the moving particles in all the space and in far greater
amount and intensity than when burnt in a mass or bed on the coal grate with corre-
spondingly more effective or perfect combustion and greater production and intensity
of heat in a given space.
A modification of the above process consists in injecting pulverised coal or similar
finely divided fuel into and about the frame of an injected oil fire, and keeping.
the coal in suspension so that the combustion of the coal is largely facilitated by
the oil fire and in such manner that the coal is consumed without coming in
contact with the oil that sustains the oil fire, which it is desirable to avoid because
when oil is projected on or comes in contact with the coal in the combustion
chamber it seems to extract suddenly from the coal the more volatile portions which
burn and are consumed readily and leave the residue hard and slaty, difficult to burn
and liable to choke the furnace.
While it is proposed to use any suitable means of maintaining the suspension of the
atoms of coal long enough to effect the mixture of the atoms, as by showering the
same from the upward portions of the chamber into which the fine coal may be
injected, along with air for combustion, the means that have been adopted consist of
air jets or blasts, injected into the fire chamber in such a manner as to produce
currents counter-currents, eddies, whirls and cycles calculated to bear up and
distribute the fine coal until consumed, the coal being preferably introduced along
with and by said jets or blasts, but may be otherwise introduced if desired; and
for supplying the oil or other hydrocarbon or gas fuel, sectional burners are
employed located in different sections of the lower portions of the furnace chamber,
with ample space between and below them for the precipitation of the ashes.
below them from the coal fire or injector burners such as steam jet burners,
etcetera.
The invention is applicable without material alteration to an ordinary return
flue boiler provided with the usual well known furnace consisting of a combustion
chamber provided with a fire door, an ash pit, bridge wall and flue back of the bridge
wall.
In such furnace deflectors are provided of refractory material one of which is
below the fire door and two facing each other in the crown sheet of the chamber, and
with an injector for air to be forced in, preferably but not necessarily, at the back of
the chamber by a fan or other means, and coal dust charged into the air spout by a

page_text: screw feeder or other suitable means to be carried along for feeding the furnace and
mixing and combining with the air and held in suspension for combustion in it. The
blast first traverses the chamber a little above the ash pit spreading more or less, then
being turned upward violently by the first deflector, and coming in contact with one
of the deflectors in the crown of the furnace is projected forward against the other
deflector by which it is turned downward into the incoming blast which takes
along with it any unconsumed particles and provents them from falling into the ash
pit unconsumed.
For adapting the above appliances to a locomotive fire box, the air and fuel
injecting tubes may have numerous branches with nozzles entering near each side
from below the side walls and projecting upward into the opposite angles so as to
meet over the centre of the chamber and produce gyrating cycles by their counter-
action, thereby being adapted to maintain the suspension of the coal atoms until
consumed.
As
Together with the above process and apparatus for maintaining the fire of coal
atoms an auxiliary fire of hydrocarbon or gas fuel is combined in various ways.
an ordinary fire of uniform spread would not be practicable on account of its liability
to clog, sectional or separate burners with wide spaces between are employed, through
which the falling ashes from the upper fire may pass to the ash pit, said burners being
of such limited transverse extent that the ascending currents from them will turn
aside into the ash pit such matters as are liable to fall into them and deaden or choke
the fire and thus be self protecting so far as such falling substances from the upper
fire are concerned. These burners may consist of trough shaped drawers adapted to
slide in and out of the furnace through openings in one side, so that they can be
drawn out for cleaning and repair, if desired, to which troughs, oil may be supplied
by suitable feed pipes from any suitable source of supply. The trouglis should also
be perforated in the upper portions of the sides for the admission of air, and the
upper edges preferably flanged and the flanges perforated to admit air from below
for better admixture with the gases and vapours arising from the burners. The
troughs will also be covered with wire gauze and partially filled with a refractory or
refractory and absorbent material, as porous stone or asbestos or both, some portions
of which may form wicks projecting through the interstices of the wire gauze to take
up the oil and vapours.
By the modification of the above process and apparatus the pulverised coal or
other solid fuel is injected into the fire chamber, ignited and caused to gyrate,
circle or swirl in and about the chamber to ensure complete combustion of the
particles or atoms of the fuel, the same as above described, but the oil, gas or
vapour, or other hydrocarbon fuel is injected at the same time into the fire chamber
by compressed air or steam so as to receive the coal atoms in the oil flame, but
not in such juxtaposition as that the oil will mix with the coal prior to the combustion
of the oil.
The apparatus for operating this process is substantially the same as that above
described so far as relates to the construction of the furnace and the contrivances for
feeding and deflecting the atomised fuel. Together with such apparatus a stean
nozzle in an air induction tube and with an oil feeding pipe is employed, the steam
nozzle being placed inside the air tube, and the oil feeding pipe connecting with the
air tube. This apparatus is introduced in the fire door and discharges into the chamber
from the side opposite that from which the coal jet comes for more effectual
commingling of the oil flame and coal jets and the better maintenance of the cycles,
whirls, etcetera, for bearing up the finely divided coal. The oil pipe is arranged to
drop the oil onto the steam nozzle near the end of the latter for the mixing of the air
and oil around said nozzle, and drawing them together off the end of the nozzle into.
the steam. Said oil pipe will connect with a reservoir and the steam will have
suitable connection with the boiler for the supply of steam.
In practice preferably, but not necessarily, the coal will be used in much larger
proportion than the oil for economical results. Thus, together with the coal injected
into the furnace and held in suspension, oil is injected and the flame thus produced is

page_text: combined with the coal, which is thus maintained in suspension. The more intense
flame thereof (and of the gases resulting from the, decomposition of steam employed
to inject the oil) is so utilized for more intense combustion than the coal alone is
capable of, and thereby the complete combustion of the coal is insured, which if
burned alone is not as effective owing to considerable waste from precipitation of
unconsumed particles into the ash pit.
The oil flame is so projected in opposition to the coal jet that the coal atoms are
turned away and do not enter the oil flame far enough to reach the oil spray
before it is ignited and thus the coal is burned without coming in contact with
the oil.
It is to be understood that these appliances may be readily fitted to a common
boiler furnace already in use without material expense of fitting or alteration and may
be as readily removed.
+
COMPLETE SPECIFICATION.
Improved Process for Burning Coal and Hydrocarbon Fuel, and
Apparatus therefor.
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:-
These improvements in burning coal and hydrocarbon fuel in combination consists
in burning the oil or oil vapours or gas in one or more suitable burners therefor,
located in the furnace chamber'somewhat higher than the ash-pit with ample surround-
ing space for the ashes to descend into the pit without clogging these burners, and,
at the same time, maintaining a fire of coal or similar fuel around and above the oil
or vapour burner or burners with pulverised coal atoms in suspension and
general distribution throughout the chamber, together with the requisite amount
of air for the support of 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 coal grate, with correspondingly more effective or perfect combustion and
greater production and intensity of heat in a given space. While it is proposed to use
any efficient means of maintaining the suspension of the atoms of coal a sufficient
length of time to effect the mixture and union of atoms while in suspension, as by the
showering of the same from the upper portion of the chamber, where it may be
introduced by a fan 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 it may be otherwise introduced if desired; and for
supplying the oil or other hydrocarbon or gas fuel, sectional burners may be employed,
that is, burners located in different sections or localities of the lower portion of the
furnace chamber with ample space between and below them for the precipitation of
the ashes below them from the coal fire or injector-burners, such as steam jet
burners, all as hereinafter described, reference being had to the accompanying
drawing.
The improvements further consist of a contrivance composed of an injecting

page_text: apparatus for introducing the pulverised coal into and about the flame of an injected
oil fire and keeping the coal in suspension so that the combustion of the coal is
largely facilitated by the oil fire, and in such manner that the coal is consumed
without coming in contact with the oil that sustains the oil fire, which it is desirable
to avoid, because, when oil is projected on or comes in contact with the coal in the
combustion chamber, it seems to extract suddenly from the coal the more volatile
portions which consume readily and leave the rest of the coal hard and slaty, so that
it does not burn readily and becomes a compact mass that chokes up. The coal in a
finely comminuted state, and air, are injected together into the furnace chamber
above a still air space for the reception of the ashes, and, by suitable appliances,
caused to deflect upwards, over and backward along the incoming jet, so that, for a
time, the coal is maintained in suspension by the forces of the said incoming jet for
more rapid and effective combustion, and so that the larger particles not yet consumed
and falling into the incoming jet will be continued in suspension by being again
taken along by said jet; and at the same time, the liquid hydrocarbon fuel is also
injected by compressed air or steam so as to receive the coal atoms in the oil flame,
but not in such juxtaposition as that the oil will mix with the coal prior to the
combustion of the oil, all as hereinafter fully described.
In the accompanying drawings:-
Figure 1 is a longitudinal sectional elevation of an ordinary boiler furnace with
apparatus for injecting and maintaining the suspension of the coal atoms, together
with apparatus for maintaining an auxiliary fire of hydrocarbon fuel in the lower
portion of the combustion chamber;
Figure 2, a transverse sectional elevation of a locomotive boiler furnace with
similar apparatus ;
Figure 3. a horizontal section of Figure 2;
Figure 4 represents a longitudinal sectional elevation of a boiler furnace with
apparatus for introducing pulverised coal into and about the flame of an injected oil
.fire illustrating the second part of the improvements.
In Figure 1, a represents an ordinary return-flue boiler, the combustion-chamber
of the furnace, d the fire-door, e the ash-pit and the flue back of the bridge-wall y.
In such a furnace are provided deflectors hij 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 com-
bustion by it.
It will be seen that the blast first traverses the chamber a little above the ash-pit,
spreading more or less. 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 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 method of consuming coal atoms in suspension to the
combustion-chamber b of a locomotive-boiler fire-box n, the injecting-nozzle may have
numerous branches entering near each side from below the side walls of the fire-box
and projecting upward into the opposite angles, 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. 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 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.
Together with the fire of coal atoms thus maintained throughout the chamber

page_text: generally, there is combined also an auxiliary fire of hydrocarbon or gas fuel in
various ways, as oil burners in the lower portion of the furnace at or about the
locality of the ordinary fire-bed, or one or more injector-burners 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 feed and other causes, and also of adding to the
capacity of the furnace for useful effect. As an ordinary 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 or separate burners p are employed with :
wide spaces between them, through which the falling ashes from the upper fire may
descend into the pit, said burners being of such limited transverse extent 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 matters of the upper
fire are concerned. These burners may consist of trough-shaped drawers, to which
troughs oil may be supplied by suitable feed-pipes s from any suitable source of
supply. The troughs will be perforated in the upper portions of the sides for the
supply of air, through which air will be distributed in jets from below for the better
admixture with the gases and vapours rising from the burners. The troughs will
also be charged with refractory or refractory and absorbent material, as porous
stone w¹ or asbestos, or both, some portions of which, particularly of the latter, may
extend up through holes in the wire gauze for wicks to take up the oil and vapours.
Instead of these burners, injector-burners-such as make use of a steam-jet for
injecting and distributing oil or gas-may be used.
My correspondent is aware that coal and oil have been burned or attempted to be:
burned by injecting oil upon the coal-bed in the furnace chamber, which, it is to be
noted, is the reverse of the improved process which is claimed-that is, injecting the
(pulverised) coal into, upon or above the oil fire. When oil is projected on a coal
fire to be consumed, it seems to suddenly extract from the coal the more volatile
portions, which consume readily and leave it hard and slaty, which residue does not
burn readily, but soon dies out, and has been found impracticable and so ineffective
as to be too expensive as compared with coal alone in the usual methods.
In the furnace, Figure 4, or any other approved or suitable furnace, there is pro-.
vided, for injecting and maintaining the fine coal in suspension, the fan-blower 1,
nozzle k and a feed-ho per 1, said hopper being connected with and discharging a
continuous streak:n of the fine coal into the discharge pipe m of the fan, so as to be
injected into the furnace through nozzle k along with the last of air from the fan and
to be projected upward, backward and along the incoming jet, as by the pan-
deflector n, on which the incoming jet first impinges and is turned upward, deflector o
in the upper part of the chamber projecting it backward over the incoming jet and
deflector p projecting the unconsumed particles downward again into the same, thus
maintaining continuous cycles of the coal until wholly consumed while in suspension
and together with the coal thus injected and held in suspension. Oil is also injected
and thus the flame thereof is produced and combined with the coal while being thus
maintained in suspension to utilise the more intense flame thereof and of the gases
resulting from the decomposition of steam employed to inject the oil for more intense
combustion than the coal is capable of alone, and thereby insure the complete com-
bustion of the coal which, if burned alone, is not as effective, owing to considerable
waste through the precipitation of a considerable percentage of unconsumed particles
into the ash-pit. For this purpose, there is employed a steam nozzle q in an air-
induction tube 8, with an oil feeding pipe t introduced at the fire-door and discharging
into the coal jet from the side of the furnace opposite to that from which the coal-jet
comes for the more effectual commingling of the oil-flame and coal-jet and the better
maintenance of the cycles for bearing up the coal. The oil-pipe is arranged to drip
on the steam nozzle near the end of the latter, for the mixing of the air and the oil
around said nozzle and drawing them together off the end of the nozzle into the
steam. Said pipe will be connected with a reservoir, and the steam nozzle will have
suitable connection with the boiler for the supply of the stean.
In practice the coal will be used in much larger proportions than the oil for the
.

page_text: most economical results; but my correspondent does not limit himself in the matter
of proportions.
The ashes will settle down in the eddies at the sides of the coal-injector to the ash-
pit or in the space behind the bridge-wall.
The oil flame is so projected in opposition to the coal-jet that the coal atoms are
turned away, so that they do not enter the oil fire far enough to reach the oil-spray
before the oil is ignited, and thus the coal is burned without coming in contact with
the oil.
It is to be understood that these appliances may be readily fitted to a common boiler
furnace already in use without material expense of fitting or alteration and may be as
readily removed.
Having now particularly described and ascertained the nature of the said inven-
tion, 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 coal and oil in combination, which consists in main-
taining independently-supplied separate and locally distributed oil-fires in the lower
portion of the furnace chamber, producing an essential portion of the heat generated,
and at the same time separately injecting fine coal into the furnace above the oil-fires,
and for a time maintaining it in suspension over and about the oil-fires, substantially
as described.
2. The method of burning coal and liquid bydro-carbon fuel 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 liquid hydro-
carbon fuel below the injected fine fuel in independent or separate burners, between
which the coal-ashes are precipitated, substantially as described.
3. In a boiler furnace, the combination, with the fire-box provided with an upwardly
curved deflecting-plate located about midway of the fire-box, a pulverised fuel injector
communicating with the rear portion of the fire-box opposite the deflecting plate, and
an oil, steam, and air injector communicating with the front of the fire-box on a
different plane from that of the pulverised fuel injector, substantially as described.
4. In a boiler-furnace, the combination, with the fire-box having an arched roof
terminating in a depending deflecting-plate located in front of the rear of the fire-box
and an upwardly curved deflecting plate located about midway of the fire-box, a
pulverised fuel injector communicating with the rear portion of the fire-box opposite
the deflecting plate, and an oil, steam, and air injector communicating with the front
of the fire-box on a different plane from that of the pulverised fuel injector, sub-
stantially as described.
Dated this 26th day of Amil 1000