Year: 1899

page_text: пиртомещение In Doner гигпасер.
I, JOHN COWAN, Managing Director of the Stirling Boiler Company, Limited,
of 2, St. Andrew's Square, Edinburgh, do hereby declare the nature of this inven-
tion to be as follows:-
My invention relates to improvements in boiler furnaces, and has for its object
to enable coal, coal dust, or the cane refuse known as megass, or wood to be used
at will for heating a boiler.
One part of my invention consists in providing a combined furnace one part of
which is suitable for burning megass or other similar fuel, and the other part
of which is suitable for burning coal, for heating a boiler, these two furnaces
being so combined that the change can be readily made from the use of the one
to the use of the other, and so arranged that they do not interfere the one with
the other.
A second part of my invention consists in providing a combined furnace, one
part of which is suitable for burning coal dust with air, and the other part of
which is suitable for burning coal in the ordinary way, these being so combined
that the change can be readily made from burning coal dust to burning ordinary
coal.
A third part of my invention consists in a special form of improved coal
furnace with inclined grate.
I will describe my present invention as applied to a water tube boiler of what
is known as the Stirling type, that is, in which certain upper drums containing
steam and water are connected to lower mud drums by banks of tubes among
which the furnace gases are made to pass in a direction mainly at right angles to
the length of the steam drums.
In carrying my invention into effect according to one modification in such a
boiler at what is usually the front end I provide an arrangement for burning
coal. At the opposite end, or the back of the boiler, I provide a furnace suitable
for burning the cane refuse known as megass.
This cane refuse furnace is con-
nected with the boiler tube space by a combustion chamber passing below the
main part of the boiler and entering the front combustion chamber just where the
flame from the coal fire would rise among the tubes, in the usual course.
The megass furnace is preferably of a special type, which is found to be very
satisfactory. In it a horizontal grate is provided in the lower part, two doors
being arranged-one to control the ingress of air below the grate, and the other
adapted to open for lighting the fire, or for cleaning the fire out above the grate.
Above the grate an inclined plate of fire-brick or other material is arranged at a
suitable angle and in such a position that, when the megass slides down it falls
off the inclined plate on to the grate, and piles up thereon in a heap of triangular
section. When the pile has reached to about the level of the bottom of the in-
clined slide, the inflow of megass is automatically stopped by this pile until the
pile falls by combustion. The slide is placed at the proper angle of repose, so that

page_text: this stoppage will take place when the pile has become high enough to act as a
stop. The slide is fed from an elbow, having its greatest section where it delivers
megass on to the slide, and having its least section where the megass is fed in
from the outside.
I may provide, in the side wall of the furnace, at the grate, doors, which can be
opened for the insertion of wood fuel. The roof of the furnace is provided also
with a depression, just to the rear of the fire grate, so that air coming in from
the megass feed will be deflected downwards on to the fuel burning on the grate.
The flame passes from the fire over a bridge just to the rear of the grate then
under the mud.drums of the boiler which are protected by a suitable fire-brick
arch. The flame and hot gases are then deflected upwards, and enter among the
first bank of tubes of the boiler. They then follow the usual course as deflected
by the fire-resisting baffle-plates. Just beyond the point where these burning
gases are deflected upwards among the tubes, the grate for coal burning is situ-
ated. This grate is arranged at an angle and a feeding elbow of a similar con-
struction to that for megass is provided to deliver coal on to the inclined grate.
The inclined grate lies at or near the angle of repose, and a narrow, horizontal grate
is provided at its lower end just against a vertical part of the brickwork. The
brickwork and this narrow fixed grate form a stop for the fuel, which, as it feeds
through the elbow on to the grate distributes itself in a layer of even thickness
over the grate. The inclined grate may be pivoted at one end, so as to allow of
its angular adjustment. I may also place this inclined grate on a slightly lower
level than the mouth of the delivering elbow. Between the end of the elbow
and the top end of the grate I may place a small door, joining the two, and this
door can be opened outwards for getting at the top of the grate for cleaning
purposes. I also provide a door or other suitable means for cleaning out below
the grate, and for regulating the supply of air below the grate.
may also provide means for the injection of steam or steam and air at the bend
of the elbow delivering coal on to the grate.
With this type of inclined grate all that requires to be done to use the megass
furnace is to close the coal and air inlet apertures, and start up the fire immediately
in the megass furnace. Similarly, if no megass is available all that is required
to enable the coal fire to be used is to close up the air and megass inlet to the
megass furnace.
In carrying out a further part of my invention I provide, instead of the megass
This coal dust
furnace, an arrangement adapted to burn coal dust with air.
burner I fit on to the back of the boiler, with suitable feeding arrangements,
the combustion chamber of this coal dust furnace is placed below the mud drums
of the boiler and suitable fire-brick arching is provided to protect these mud
drums. At what is normally the front part of the boiler I provide bearers for
supporting the usual fire-bars, and below these the necessary ash-tray supports.
When it is desired to use ordinary coal, the coal dust apparatus and its air inlet
are closed.
The fire-bars are then placed in position together with the ash-tray.
The boiler becomes then an ordinary boiler using coal, which is fed in by a
suitable door from the boiler front. The inclined grate and its coal feed herein-
before described may be arranged instead of this ordinary grate, and used in
connection with the coal dust burning furnace just described.
1
די
1000
MARKS & CLERK,
18. Southampton Buildings, London, W.C.,
13, Temple Street, Birmingham, and
25, Cross Street, Manchester,
Agents.

page_text: Improvements in Boiler Furnaces.
I, JOHN COWAN, Managing Director of The Stirling Boiler Company, Limited,
of.2, St. Andrew's Square, Edinburgh, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following stateinent:-
My invention relates to improvements in boiler furnaces, and has for its object
to enable coal, coal dust, or the cane refuse known as megass, or wood to be used
at will for heating a boiler.
One part of my invention consists in providing a combined furnace one part of
which is suitable for burning megass or other similar fuel, and the other part of
of which is suitable for burning coal, for heating a boiler, these two furnaces
being so combined that the change can be readily made from the use of one
to the use of the other, and so arranged that they do not interfere the one with
the other.
A second part of my invention consists in providing a combined furnace, one
part of which is suitable for burning coal dust with air and the other part of
which is suitable for burning coal in the ordinary way, these being so combined
that the change can be readily made from burning coal dust to burning ordinary
coal.
A third part of my invention consists in a special form of my improved coal
furnace with inclined grate.
I will describe my present invention as applied to a water tube boiler of what
is known as the Stirling type, that is, in which certain upper drums containing
steam and water are connected to lower mud-drums by banks of tubes among
which the furnace gases are made to pass in a direction mainly at right angles to
the length of the steam drums.
In the accompanying drawings which illustrate my invention:-
Figure 1 is a sectional elevation of a Stirling boiler with furnaces constructed
and arranged according to one modification of my invention.
.
Figure 2 is a sectional plan of the same on the line A A of Figure 1.
Figure 3 is a front elevation of the same.
Figure 4 is a back elevation of the same.
Figure 5 is a sectional elevation of a Stirling boiler with furnaces constructed
and arranged according to a second modification of my invention.
Figure 6 is a sectional elevation of a Stirling boiler with furnaces constructed
and arranged according to a third modification of my invention.
Figure 7 is a front elevation of the same, and
Figure 8 is a back elevation of the same.
Referring firstly to Figures 1, 2, 3 and 4, a, b, c, d and e are the drums of the
Stirling boiler and f, g, h and k the banks of tubes forming the principal heating
surface of the boiler. At what is usually the front end of the boiler I provide a
furnace for burning coal, and, at the opposite end, I provide a furnace m suit-
able for burning the cane refuse known as megass. The megass furnace m is
connected with the boiler tube space by a combustion chamber n passing below
the main part of the boiler and entering the front combustion chamber o just
where the flame from the coal fire would rise among the tubes if the coal fur-
nace were in use.
The megass furnace is preferably of a special type which is found to be very
satisfactory. In it a horizontal grate p is provided in the lower part and also
two sets of doors q. q and r,r. The doors 9.9 are used to control the ingress of

page_text: air below the grate and the doors rr are adapted to open for lighting the fire or
for cleaning the fire out above the grate. Doors ; may also be provided for gain-
ing access to the combustion chamber n., An inclined slide s of firebrick or other
suitable material is arranged above the grate at a suitable angle and in such a
position that, when the megass slides down it falls off the inclined slide on to
the grate and piles up thereon in a heap of triangular section. When the pile
has reached to, about the level of the bottom of the inclined slide, the inflow of
megass is automatically stopped, by the pile until the latter falls by combustion.
The slide is placed at the proper angle of repose so that this stoppage will take
place when the pile has become high enough to form an obstruction. The slide
is fed by an elbow having its greatest section where it delivers megass on to the
slide and having its least section where the megass is fed in from the outside.
I may provide in each side wall of the megass furnace m a door u which can
be opened for the insertion of wood fuel.
The roof of the megass furnace m is provided with a depression situated over
the innermost part of the fire grate p so that air coming in from the megass feed
will be deflected downwards on to the fuel burning on the grate. The flame
passes from the fire 'over a bridge i just beyond the grate and then along the com-
bustion chamber which passes under the mud drums d and e of the boiler, being
separated from the drums by a suitable firebrick arch w. The flame and hot
gases are then deflected upwards and enter among the first bank of tubes f of the
boiler, being thereafter guided among the other tubes of the boiler by suitable
baffle plates in a usual manner. Just in front of where these hot gases are
deflected upwards among the tubes f is situated the grate for burning coal.
Above the grate the doors z, 2, 2, are provided for the insertion of coal fuel, while
ash pit doors 2, 2, 2, or other suitable means are provided below the grate to facili-
tate the cleaning of the grate and to regulate the supply of air below it.
I may also provide doors y, y, for the insertion of wood fuel.
}
.
Referring now to Figure 5 which shows another modification of my invention,
the coal grate 3 is here arranged at an angle and a feeding elbow 4 of a similar
construction to the elbow t, just described, is provided to deliver coal on to the
inclined grate 3. The inclination of this grate is at or near to the angle of repose
and a narrow horizontal grate 5 is provided at the lower end of the inclined grate
just against a vertical part of the brickwork 6. This piece of brickwork and the
horizontal grate 5 form a stop for the fuel which as it feeds through the elbow
on to the inclined 'grate,' distributes itself in a layer of even thickness over the
grate.
....
The inclined grate 3 may be pivoted at either end so as to allow of angular
adjustment. I may also place this' inclined grate on a slightly lower level than
the mouth of the delivery elbow 4 and between the bottom end of the elbow and
the top end of the inclined grate I may place a small door 7. to be used for get-
ting at the top of the grate for cleaning purposes. I may also provide a pipe 8
and a cock 9 for the purpose of injecting steam or air and steam at the bend of
the elbow 4.
i
....
With these two types of combined coal and mégass furnaces, all that requires
to be done to use the megass furnace is to close the coal and adjoining air inlet
apertures and start up the fire in the megass furnace. Similarly, if no megass is
available, all that is required to enable the coal fire to be used is to close up the
air and megass inlets to the megass furnace:
1
Referring now to Figures 6, 7;' and 8, I provide instead of the megass furnace.
an arrangement adapted to burn coal dust with air. I fit the coal dust burner 18
which is of any usual type at the back of the boiler and provide it with suitable
feeding arrangements. The combustion chamber 10 of this coal dust furnace is
placed below the mud drums d and e and is separated from these drums by the
firebrick arch 11. At what is normally the front part of the boiler is situated
an ordinary coal furnace 16. provided with bearers 12, 12 supporting the usual
firebars 13 and below these the bearers 14; 14 supporting the movable ash tray 15.

page_text: This ash tray acts as a damper to cut off communication between the coal dust
combustion chamber 10 and the ordinary coal furnace 16.
When it is desired to use ordinary coal, the coal dust apparatus and its air inlet
are closed. The fire-bars 13 are then placed in position together with the ash
tray 15. The boiler then becomes an ordinary boiler using coal which is fed in
through suitable doors 17, 17 in the boiler front.
The inclined grate with its coal feed hereinbefore described may be arranged
instead of the ordinary grate, and used in connection with the coal dust furnace
just described.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, declare that what
I claim is
1. In an externally fired boiler, the combination of a furnace for burning me-
gass with a furnace for burning coal, the two furnaces being at opposite ends of
the boiler and the megass furnace having a combustion chamber underneath the
boiler which conducts the hot gases to the other end of the boiler, substantially
as described.
2. In an externally fired boiler, the combination of a furnace for burning me-
gass with a furnace for burning coal the two furnaces being at opposite ends of
the boiler, the megass furnace having a combustion chamber underneath the
boiler which conducts the hot gases to the other end of the boiler, and the coal
furnace having an inclined and a horizontal grate, substantially as and for the
purpose described.
3. In an externally fired boiler, the combination of a furnace for burning coal-
dust with air with a furnace for burning coal, the two furnaces being at opposite
ends of the boiler and the coal dust furnace having a combustion chamber under-
neath the boiler which conducts the hot gases to the other end of the boiler sub-
stantially as described.
4. In an externally fired boiler, the combination of a furnace for burning coal-
dust with air with a furnace for burning coal, the two furnaces being at opposite
ends of the boiler, the coal-dust furnace having a combustion chamber underneath
the boiler which conducts the hot gases to the other end of the boiler, and the
coal furnace having an inclined and a horizontal grate, substantially as and for
the purpose described.
5. In an externally fired boiler, the addition to the combination as claimed in
Claim 3 of a removable ashpan serving as a damper, substantially as and for the
purpose described.
Dated this 5th day of January 1900
Dated this 5th day of anuary 1900
MARKS & CLERK,
18, Southampton Buildings, London, W.C.,
13, Temple Street, Birmingham, and
25, Cross Street, Manchester, Agents.
ary 1900
MARKS & CLERK,
18, Southampton Buildings, London, W.C.,
13, Temple Street, Birmingham, and
25, Cross Street, Manchester, Agents.