An Improved Method of and Apparatus for Causing Complete. Combustion of Fuel in Furnaces for Heating Purposes, and also Effecting the Abatement of Smoke Nuisance.
Year: 1889

page_text: Date of Application, 27th Apr., 1889
Complete Specification Left, 12th Aug., 1889-Accepted, 14th Sept., 1889
PROVISIONAL SPECIFICATION.
An Improved Method of and Apparatus for Causing Complete.
Combustion of Fuel in Furnaces for Heating Purposes, and also
Effecting the Abatement of Smoke Nuisance.
.We ANDREW HARKNESS and WILLIAM THOMAS HARKNESS of William Street
Sunderland in the County of Durham Iron and Steel Merchants, do hereby declare
the nature of this invention to be as follows:-
Our invention relates to an improved method of combustion of fuel in all furnaces
for heating purposes, being equally applicable to furnaces for the following among
other purposes.
Marine boilers, Locomotive boilers Boilers for Stationary engines, Boilers for
Portable Engines. For Air furnaces for smelting Iron Steel and other metals, for
puddling furnaces for mill and forge furnaces, for heating furnaces as used by Ship-
builders, Engineers, Boiler builders and others.
The method of carrying out our Invention is as follows.
Air is conducted from the outside of the furnace or boiler to the combustion
chamber by means of pipes or conduits of Iron, Fire brick, Fire Clay or other suitable
material, so that in its passage this air may be heated to as high a temperature as
possible. This heated air is conducted to that part of the combustion chamber where
it will best mix with the furnace gases. This in most cases will be at the bridge
which for this purpose may be built or made hollow with numerous appertures for the
exit of the heated air. In certain cases the heated air may be allowed to mix with
the furnace gases further to the rear of the chamber or furnace so as to meet the
said gases.
The opening for admission of the air from outside the boiler or furnace will in
many cases be at the front, but in other cases it will be preferable to draw the air from
the region of the uptake or chimney so that in its passage towards the combustion
chamber, it will be benefitted by passing through pipes or conduits surrounded by
the waste heat. Whether the cold air be admitted at the front or in the rear its
passage into the combustion chamber may be materially assisted by a jet or jets of
steam drawn either from the boiler direct or from the waste steam pipe or from any
other convenient source.
The above indicates our method of causing complete combustion of fuel. Based
upon this complete combustion similar arrangements for the admission of heated air
will prevent the escape of smoke and noxious fumes into the atmosphere.
Dated this 26th day of April 1889.
ANDREW HARKNESS.
WILLIAM THOMAS HARKNESS.
COMPLETE SPECIFICATION.
An Improved Method of and Apparatus for Causing Complete
Combustion of Fuel in Furnaces for Heating Purposes, and also
Effecting the Abatement of Smoke Nuisance.
We, ANDREW HARKNESS and WILLIAM THOMAS HARKNESS of William Street
Sunderland in the County of Durham Iron and Steel Merchants 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 :-
Our invention relates to an improved method of combustion of fuel in all furnaces
for heating purposes, being equally applicable to furnaces for the following among

page_text: other purposes, Marine Boilers, Locomotive Boilers, Boilers for Stationary Engines,
Boilers for Portable Engines; Air Furnaces, for smelting Iron Steel and other metals,
Puddling furnaces, Mill and Forge furnaces, Heating furnaces as used by Shipbuilders,
Engineers, Boilerbuilders, and others.
We will at once illustrate the invention by reference to the drawings: similar
letters indicate similar parts in all the figures.
Fig. 1 is a sectional elevation of a furnace having an opening A for admission of
cold air, a pipe B beneath the fire bars, a bend or siphon C, a return pipe D above
the fire bars and a bend or mouthpiece É near the front of the furnace for discharging
the heated air. The mouthpiece E points backwards either directly or obliquely over
the surface of the fire.
Fig. 2 is a sectional elevation of a furnace with parts A. B. D as in Fig. 1. G is
a hollow bridge with apertures for the admission of the rear ends of pipes B and D,
the front end of the pipe D. entering into or jointed with a hollow dead or dumb
plate F. and from another aperture in the dead or dumb plate F. a mouthpiece E
discharges the heated air over the fire as mentioned above, the upper pipe D in this
case being on a line with the fire bars.
Fig. 3 is a sectional elevation of a furnace with parts A. B. C. D. as above, but
instead of the mouthpiece E at the front of the furnace there is a third length of pipe
returning the air to the hollow bridge G which has apertures for the discharge of the
heated air.
These apertures may be at the front or at the top or at the rear of the
hollow bridge, or instead of numerous apertures in the hollow bridge the mouthpiece E
may be used for discharging the heated air over the fire towards the front of the
furnace directly or obliquely. The three lengths of pipe shown in Fig. 3 may be
two in the ash-pit and one in the furnace or two in the furnace and one in the
ash-pit.
In the three types above described the numbers of lengths of pipe may be increased,
and may be arranged in any convenient way with regard to the fire bars. Any or all
of these pipes may have numerous apertures for the discharge of the heated air above
or beneath the fire.
Figs. 4. 5 and 6 are front elevations partly sectional, of Figs. 1 2 and 3 respectively
showing in each case two sets of pipes one at each side of the furnace.
The method of using the apparatus above described is as follows:-When the
fire in the furnace is lighted, the draught of the chimney or funnel causes the cold
air to enter at A into the pipe in its passage along which it becomes so greatly heated
that when it is discharged from the mouthpiece E or from apertures in the pipe or
bridge the oxygen of the air combines eagerly with the gaseous hydro-carbons of the
fuel, causing intense heat in the furnace or boiler and preventing the escape of free
carbon in the form of smoke. The greater the heat in the furnace the stronger the
draught in the chimney and the greater the quantity of cold air drawn into the pipe;
the greater the quantity of air admitted the more complete the combustion and the
greater the heat generated.
The pipes, the dead plate, and the hollow bridge may be made of Iron, Steel, Fire
brick Fire Clay, Crucible Clay, or any other suitable metal or material, and may be
coated over with any suitable composition for further resisting the intense heat of the
furnace.
In the description of Fig. 3 the apertures in the bollow bridge may discharge the
heated air towards the front of the furnace to mix with the gases as they are formed,
or upwards towards the crown of the furnace, or backwards towards the combustion
chamber so as to mix with the gases in their passage towards the chimney.
Instead of the cold air being admitted at the front of the furnace as shown in the
drawings it will, in certain cases, be preferable to admit it in the region of the uptake
or chimney, so that in its passage along the pipes, towards the bridge, its temperature
may be raised by the waste heat. Whether the cold air be admitted at the front or
in the rear or other convenient part of the furnace or boiler, its discharge may be
greatly assisted by a jet or jets of steam drawn either from the boiler direct, or from
the waste steam pipe or from any other convenient source.

page_text: We do not restrict ourselves to the exact details and arrangements herein shown
and described, as the same may be varied and the apparatus modified in various ways
according to circumstances without departing from our invention.
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. In our method of causing complete combustion and abatement of smoke nuisance,
the use of a hollow bridge constructed either of Iron, Steel Fire brick, Fire Clay,
Crucible Clay, or of any other suitable metal or material and having apertures for the
passage of the heated air.
2. The use of a hollow dead plate or dumb plate having apertures for the passage
of heated air.
3. The employment of pipes constructed of Iron Steel, Fire brick, Fire clay,
Crucible Clay, or any other suitable metal or material, within the furnace for heating
the air.
4. The employment of pipes within the furnace for discharging the heated air.
5. The employment of pipes within the ash-pit for heating the air.
6. The employment of pipes within the ash-pit for discharging the heated air.
7. The employment of pipes within the combustion chamber behind the bridge for
heating the air.
8. The employment of pipes within the combustion chamber behind the bridge for
discharging the heated air.
9. The employment of pipes within the uptake or chimney for heating the air.
10. The combination of claim 1 with any of the claims 2 to 9.
11. The combination of claim 2 with any of the claims 3 to 9.
12. The method of discharging the heated air over the burning fuel from pipes
within the furnace, the openings of the said pipes, pointing backwards either directly
or obliquely.
13. The method of discharging the heated air over the burning fuel from
perforations in the hollow bridge or from pipes near the bridge pointing towards the
front of the furnace directly or obliquely.
14. The method of discharging the heated air over the burning fuel sideways either
directly or obliquely from apertures or perforations in the pipes at the side of the
furnace.
15. The method of discharging the heated air from perforations in the hollow bridge
or from apertures in the pipes, so that it may intimately mix with the furnace gases
in the combustion chamber.
16. The employment of a jet or jets of steam to assist the discharge of the
heated air.
17. The combination of any or all the methods 12 to 16 to discharge the heated air,
and mix with the furnace gases.
18. The combination of claim 10 or claim 11 with claim 17.
Dated this 9th dow of Angust 1889