Improvements in Obtaining More Perfect Combustion in Steam Boilers or other Furnaces, and in Apparatus therefor.
Year: 1894

page_text: Date of Application, 28th May, 1894
Complete Specification Left, 28th Feb., 1895-Accepted, 30th Mar., 1895
PROVISIONAL SPECIFICATION.
Improvements in Obtaining More Perfect Combustion in Steam
Boilers or other Furnaces, and in Apparatus therefor.
I, HUGH IORWERTH ROBERTS, of 44 Breeze Hill, Bootle in the County of
Lancaster, Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to obtaining more complete combustion of fuel and the
gases generated therefrom in any kind of furnace. It is well known that coal or
other combustible material employed in furnaces, flues or the like, does not undergo
complete combustion by reason of the insufficiency of the supply of oxygen which
is necessary for such combustion, and hence smoke is given off, the amount of air
usually supplied being entirely insufficient to provide the amount of oxygen which
is essential to consume the smoke and gases.
In carrying my invention into effect as applied to steam boiler furnaces, the plan
I prefer is to build up the furnace bridge to the top of the furnace to prevent the
passage of any unconsumed gases or smoke into the chimney and to form the fire
bars with a dip near this bridge so as to leave an opening under it through which
consumed gases only can pass from the hottest part of the fire on their way to the
chimney flues. These chimney flues have preferably their entrance near the fire
bars where the fire is hottest and where the hot consumed gases are drawn off.
In conjunction with the furnace, I provide a smoke flue or flues for collecting the
smoke and unconsumed gases generated from the fire and which cannot be
discharged at the bridge by reason of its being built up to the top, also an injector
for supplying an artificial current of air to the furnace and for sucking in the
smoke and gases from the smoke flue. The injector is so constructed that one end
is open to the outside air and the other open to the fire bars, and it has a further
opening in its centre which opens to the smoke flue. The opening for air may be
either direct as described or through a perforated fire door and front plate. The
injectors are of sufficient size and number to give an ample supply of air to the fire
and also to draw in the gases and smoke from the smoke flues.
The mode of action is as follows-
The unconsumed gases in the form of smoke etcetera are collected by the smoke
flue or flues and conducted to the injector, where the draught produced by the heat
of the fire, causes a rush of air. The air, therefore, passing through the injectors.
sucks in the smoke and gases from the smoke flues and mixes therewith at a high
temperature. This mixture of air, gas and unconsumed coal in the form of smoke
beirg delivered under or near the furnace and having to pass through, and be
exposed to the hottest part of the fire where the fuel is incandescent, all the smoke
and combustible gases will be consumed, together with the particles of carbon
suspended therein, and only the vitiated air and consumed gases are carried up the
chimney flue. The injector in drawing the smoke and gases from the smoke flue
relieves the pressure there and causes the fire to burn up through the material in
the course of combustion. Should a forced draught be required to accelerate the
combustion, a steam jet may be fixed in the air injector or air forced in by means
of a fan or blower. Instead of bringing the smoke and unconsumed gases down
through the smoke flues, I may conduct them to the air injectors in any other
suitable manner, for instance, by means of a pipe discharging its contents into the

page_text: injectors or into a chamber through which the injectors pass in which they have
openings for sucking in smoke.
It is obvious that the invention can be applied to plate furnaces, incinerators or
any other kind of furnace and the fuel employed may be coal, refuse, street
sweepings, wood, straw, or in fact any description of inflammable material. In
plate furnaces and incinerators, where the construction of the furnace is different
from steam boiler furnaces or where there is no fire bridge, the flue opening is
placed low down near the furnace bars.
Dated this 25th day of May 1894.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
Improvements in Obtaining More Perfect Combustion in Steam
Boilers or other Furnaces, and in Apparatus therefor.
1, HUGH IORWERTH ROBERTS of 44 Breeze Hill, Bootle in the County of
Lancaster, 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 :-
This invention relates to obtaining more complete combustion of fuel and the
gases generated therefrom in any kind of furnace. My object more especially is
to provide a furnace consuming its own smoke which is specially adapted for
burning refuse, street sweepings, coal, wood, straw, or any other description of
inflammable material, and which may either be applied for use as an incinerator or
refuse destructor, or for generating steam, heating or the like.
Referring to the drawings-
Figure 1 is a sectional elevation of a single cell incinerator or refuse destructor;
Figure 2, a longitudinal section of a boiler fitted with a single injector;
Figure 3 a longitudinal section of a double tube boiler fitted with air injectors
for forced draught;
Figure 4, a sectional plan of the same showing the position of injectors;
Figure 5 a section of a twin incinerator or refuse destructor; and
Figure 6, another longitudinal section of a boiler, showing how my invention
may be applied when space is limited.
In these figures
.
A is the furnace which is built in such a way as to prevent the passage of any
unconsumed gases or smoke into the chimney, this being accomplished by closing
the usual opening for the escape of smoke above the fire and by substituting
therefor an opening or openings B near the fire bars where the fire is brightest,
these openings being in some cases just over the bars, as in Figures 1, 5 and 6,
and in others partly under or partly over the bars as in Figure 2, where only
the consumed gases can be drawn off. C are the fire bars, preferably with large
air spaces between them, E the chimney flues. In conjunction with the furnace,
I provide a smoke flue or flues G for collecting the smoke and unconsumed gases
generated from the fire, and which cannot be discharged into the chimney flue E
by reason of the usual exits being built up. H is the injector for supplying an
artificial current of air to the furnace, and for sucking in smoke and gases from
the smoke flue G. The injector is so constructed that one end is open to the
outside air and the other open to the fire bars C, while it has a further opening
in its centre which opens to the smoke flue G. The opening for air may be
either direct or through a perforated fire door and front plate.
The injectors
are of sufficient size and number to give an ample supply of air to the fire,

page_text: and also to draw in the gases or smoke from the smoke flues G. They may also
be provided with a regulator, so that the quantity of air and unconsumed gas
injected can be regulated for instance, by closing the supply of air to the
injector and the air and gases in the furnace made to circulate through and
through the material in course of combustion, and by opening the air inlet to
injector and closing the flue G only fresh air would be admitted to the fire,
which would pass through the chimney. By this means the furnace can be
regulated for burning any material. The furnace shown in Figure 1 is provided
with an opening I for filling (with close fitting door or cover), door J for cleaning
out the chimney flue E, this door having air holes to admit an extra supply of air
when required, soot doors K, L, M, for cleaning chimneys, ash-pit, and smoke flues,
N is the fire door in all the figures.
The mode of action is as follows-
The unconsumed gases in the form of smoke, etcetera, in the furnace, collect in
the smoke flue or flues G, and are conducted into the injector H where the draught
produced by the heat of the fire causes a rush of air; the air therefore passing
through the injector, sucks in the smoke and gases from the furnace and smoke
flues G and mixes therewith at a high temperture. This mixture of air, gas, and
unconsumed fuel in the form of smoke is blown or delivered under or near the
grate or fire bars C and having to pass through and be exposed to the hottest part
of the fire where the fuel is incandescent, all the smoke and combustible gases will
be consumed together with particles of carbon suspended therein, and only the
vitiated air and consumed gases are carried up the chimney flue E. Injector H in
drawing the smoke and gases from the smoke flue G relieves the pressure there
and causes the fire to burn up through the material in course of combustion.
Should a forced draught be required to accelerate the combustion a steam jet O,
Figures 3 and 4, may be applied to the air injector H, or air forced in by means of
a fan or blower.
In Lancashire, Cornish, and like boilers, to ensure the complete consumption of
smoke, the fire bridge P is built up to the top of the furnace and furthermore,
I construct the fire bars so that at the end farthest from the injector there will be
a dip in them as shown in Figure 2, clear spaces being left between these bars so
that the consumed gases can pass through to the chimney flue E. The fire at this
portion being lower than the rest, and filled with incandescent fuel will be hottest
and brightest, and will wholly consume the smoke borne along by the air, or where
space does not permit the same object can be attained by building the bridge P
and the bars as shown in Figure 6, thus leaving a space immediately over the bars
under the bridge through which only consumed gases can be drawn off. Instead
of bringing smoke and unconsumed gases down through the smoke flue G, I may
conduct them to the air injectors in any other suitable manner, for instance, by
means of a pipe discharging its contents into the injector or into a chamber through
which the injectors pass, and only having openings for sucking in smoke. By my
arrangement the fuel is burnt and has no tendency to deposit soot, and moreover
the economical value of the coal is greatly increased.
÷
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what 1
claim is :-
:-
1. A furnace having the usual opening to the chimney for the escape of smoke,
above the fire, completely closed, and an opening or openings near the fire bars,
where the fire is brightest, substituted instead, these openings being so placed in
relation to the fire that the products of combustion must pass through the
incandescent fuel before they can be discharged into the chimney flue, substantially
as and for the purpose described.
2. The use in combination with a furnace, of a flue or flues or their equivalent
such as G for collecting the smoke from the fire, and an injector, the latter so
arranged as to suck in the unconsumed gases from the said flues and deliver them

page_text: with a fresh supply of air for combustion under the grate or into the incandescent
layer of fuel, substantially as and for the purpose described.
3. In steam boiler or other furnaces, forming the fire bars with a dip or
depression near the bridge in which the incandescent fuel can collect substantially
as described and for the purpose set forth.
4. The general construction or arrangement of furnaces applicable for generating
steam, burning refuse or other purposes substantially as herein described.
Dated this 27th day of February 1895.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Birmingham, and London, Patent Agents.