Improvements in or connected with Steam Boiler Furnaces.
Year: 1897

page_text: Date of Application, 11th Feb., 1897
PROVISIONAL SPECIFICATION.
Improvements in or connected with Steam Boiler Furnaces.
I, WILLIAM BROTHERS, of Higher Clewes Chemical Works, Rawtenstall, in the
County of Lancaster, Manufacturing Chemist, do hereby declare the nature of this,
invention to be as follows:-
This invention is designed to provide for the more complete combustion of fuel
in connection with steam and other boilers, the increase of heat duty obtainable
from the fuel, the prevention or almost entire abatement of smoke at the chimney
in the raising of steam and other operations along with the entire or nearly entire
absence of the noxious carbonic oxide gas at the exit of the boiler flues.
In carrying out the invention so far as steam and other boilers are concerned I
construct a furnace or furnaces of fire bricks or tiles or other suitable materials
outside a steam or other boiler without restricting myself otherwise to the position
of such furnace or furnaces, and I construct a combustion chamber or chambers
of fire bricks or tiles or other suitable materials preferably between said furnace or
furnaces and the steam or other boiler.
Around the whole or part of the sides and upper part of said furnace or furnaces,
I build an air chamber or chambers of suitable size and dimensions composed of
fire bricks or tiles or other suitable material, and I heat said air chamber or
chambers by means of the heat from said furnace or furnaces.
I construct openings or ports of suitable size preferably in the side or sides of
the furnace or furnaces, without however restricting myself to any specific place or
places for such openings or ports, and I cause these openings or ports to lead into
or communicate with the said air chamber or chambers.
All the gases generated in said furnace or furnaces are allowed to pass through
said openings or ports into the air chamber or chambers in which the combustion
continues, the furnace or furnaces having preferably with the exception of these
openings or ports and the charging door or doors of, and the fire bars underneath,
the furnace or furnaces no other outlet or inlet.
Upon the top or tops, or at the side or sides, or at the front of the air chamber
or chambers or other convenient position, I place inlets provided with regulators
for the admission of air into said air chamber or chambers.
The regulators of the inlets to the air chamber or chambers are opened from
time to time if, or as such as may be required, to admit air to aid combustion of the .
gases when the furnace door or doors are closed.
To provide against an inrush of air into the furnace or furnaces when the furnace
door or doors are opened for whatever purpose, the regulators of the inlets for the
admission of air to the air chamber or chambers are preferably connected by a
mechanical or other contrivance to the furnace door or doors or otherwise so
arranged or adjusted as to be opened. as much.as necessary when the furnace door
or doors are opened. Dampers may also be provided for the ports or openings

page_text: leading from the furnace to the air chambers to regulate the draught or the passage
of gases therethrough.
I cause the said air chamber or chambers to communicate with the combustion
chamber or chambers, and the combustion chamber or chambers to communicate
with the boiler flue or flues.
In addition to the inlets provided with regulators for the admission of air to
the air chamber or chambers I place one or more apertures in the combustion
chamber or chambers, and provide such apertures with regulators for the admission
of air when and as required direct into the combustion chamber or chambers.
The main principle of my invention consists in obtaining by means of my furnace
in conjunction with the air chamber and combustion chamber as described and the
duly regulated supply of air thereto by means of the inlets and apertures mentioned
(when once the fuel in the furnace has become sufficiently heated and the air chamber
has become fully heated) not only a very largely increased heat duty from the fuel,
a large if not entire abatement of the smoke nuisance, but also the nearly complete
if not complete absence of the noxious and wasteful carbonic oxide gas at the exit
of the boiler flue.
In operation the fuel is thrown or fed into the furnace or furnaces upon the
burning fuel therein, a regulated amount of air being admitted preferably through
the bars of the furnace or furnaces, hydro carbon, carbonic oxide, and carbonic
acid gases being produced in the furnace or furnaces, and these gases passing through
the openings or ports of the furnace or furnaces into the air chamber or chambers
and supplied by the inlets there with such regulated amount of air as may be
required are passed into the combustion chamber or chambers where an additional
regulated amount of air may if required be admitted. In the air chamber or
chambers and in the combustion chamber or chambers the gases originally
produced in the furnace or furnaces undergo further or more complete combustion
and attain a much greater degree of heat than when they left the furnace or
furnaces the combustion being so perfect that little or no carbonic oxide is observ-
able at the exit end of the boiler flue or flues.
When the furnace or furnaces are in regular work there is little or no smoke
observable from the chimney, and further there is little or no smoke observable
from the chimney even when the furnace door or doors are opened for the purpose
of putting on fresh fuel or for clinkering owing to the mechanical or other con-
trivance adopted by means of which the air inlets to the air or combustion chambers
are opened to a greater extent when the furnace door or doors are opened, so that
the draught of the chimney acting but little upon the furnace or furnaces draws
but little additional air through the door or doors of the furnace such chimney
draught being mainly satisfied with the secondary air supplied for the time being
through the air inlets opened simultaneously or as nearly as possible simultaneously
by the mechanical or other means when the furnace door or doors are opened.
I further preferably cover the sides and top of the air chamber or chambers
and the combustion chamber or chambers with suitable materials to prevent radia-
tion and I preferably line part of the boiler flue or flues with fire bricks or tiles if
considered advisable.
If desired the furnace or furnaces may be constructed with a retort or retorts
placed above, and heated by the heat of the furnace or furnaces said retort or retorts
when so heated are first to receive the raw fuel. From said retorts the hydro-
carbon gases are passed on to the combustion chamber through a suitable opening
the partially coked fuel being raked down into the furnace or furnaces through an
aperture or apertures in the retort or retorts, and the gases generated in the furnace
or furnaces being allowed to pass into the combustion chamber or chambers, into
which latter a regulated supply of air heated or cold is admitted.

page_text: 1, WILLIAM BROTHERS, of Higher Clewes Chemical Works, Rawtenstall, in the
County of Lancaster, Manufacturing Chemist, 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 is designed to provide for the more complete combustion of fuel,
an increase of heat duty therefrom, the prevention or almost entire abatement of
smoke at the chimney and the absence or almost entire absence of the noxious
carbonic oxide gas at the exit of the flues.
It consists essentially in constructing a furnace with a furnace chamber or
chamber to receive the fuel, provided with outlets preferably at the sides, opening
into passages which lead into an air chamber or chambers preferably placed above,
to which the quantity of air admitted can be regulated, and a combustion chamber.
or chambers to which also air may be admitted, and in which secondary combustion
takes place, completely or almost completely consuming the combustible products,
and raising the gases to a high temperature.
It will be fully described by reference to the accompanying drawings.
Fig. 1. Front elevation.
Fig. 2. Transverse section on line x-x Fig. 4.
Fig. 3. Transverse section through the combustion chamber on line y-y Fig. 4.
Fig. 4. Longitudinal sectional elevation showing furnace in front of steam
generator flues.
Fig. 5. Sectional plan of same.
The furnace which is of fire bricks or other suitable material, and of any desired
size or dimensions is constructed preferably with two furnace chambers A to receive
the fuel. It is preferably of curved or dome shape at top, with a partition wall B
(when there are two furnace chambers) and grate or fire bars C placed over an
ashpan D, the said ashpan being kept supplied with water.
Behind the furnace chambers A (or in such a position as to be between the
furnace and the boiler,) are constructed combustion chrambers E. The combustion
chambers E are preferably dome shaped, similar to the furnace chambers, and
divided by a partition wall e, and provided with exit openings e¹, leading into the
flue of the boiler to be heated.
Above or around the furnace chambers A are formed air chambers or passages F,
through which all the products of combustion and also a supply of air to further
complete the combustion pass to the combustion chamber E. The air chambers F
being situated above or around the furnace, are heated by the heat passing through
the walls, as well as by the heated gases from the furnace A.
In the sides or walls of the furnace chambers A are provided a number of openings
or ports G (preferably situated at a level somewhat higher than the grate bars)
which connect the interior of the furnace chamber with passages H through which
the products of combustion pass into the air chambers F.
All the gases generated from the fuel in the furnace chambers A are caused to
pass through the openings and the passages H into the air chamber or cham-
bers F, where they mingle with a regulated supply of air, and in which the com-
bustion continues. The furnace chambers A have preferably no other outlet or
inlet with the exception of the charging doors K and the fire bars C, and the
openings G.
The air chambers F are provided with air inlets f placed in the front of the
furnace or other convenient position, through which any desired or regulated quan-
tity of air is admitted, sufficient to promote the more complete combustion of the

page_text: products from the furnace chambers A. The inlets f and the air regulators M
are preferably situated in front, but may be at the top or sides or other suitable
position.
The admission of air through the inlets f is regulated by pivoted doors or flap
valves or other regulators M. These pivoted doors or valves are regulated so as to
allow the desired amount of air as required to pass into the chamber F.
To provide against an inrush of air into the furnace or furnace chambers A,
when the furnace door or doors are opened for any purpose, the regulators M are
connected to the doors K by a chain O, passing around a pulley k on the pivot k¹
of the door, or by rods or other mechanical contrivance, so as to open more fully
with the opening of the furnace door K, and check the draught through the
furnace.
The air chamber or chambers F open into the combustion chambers E, into
which are delivered all the products or gases from the furnaces, as well as the air
admitted through the air chambers, and in this chamber E a more complete com-
bustion is effected at a very high temperature, the heated gases passing out through
the outlet openings el to the interior of the steam boiler P.
In addition to the inlets f for admitting air into the air chamber F, one or more
apertures f¹ may lead direct into the combustion chamber E. The apertures fl
may, be provided with regulators to admit a further supply of air direct into the
combustion chamber if required, but I do not restrict myself to the position in the
combustion chamber of the apertures f¹.
The main features of the invention consist in the construction of the furnace
and of the air chamber and combustion chamber with a regulated supply of air
sufficient to promote secondary combustion whereby a largely increased heat duty
from the fuel, and an entire or almost entire abatement of the smoke nuisance is
obtained, and also a nearly complete (if not wholly complete) absence of the noxious
and wasteful carbonic oxide gas at the exit of the flues.
In operation the fuel is thrown or fed into the furnace or furnace chambers A
upon the burning fuel therein, a regulated amount of air being admitted to the fuel
through the fire bars C. Hydrocarbon carbonic oxide and carbonic acid gases are
produced or generated, and these gases pass through the openings or ports G and
passages H into the air chamber or air chambers F, and are there supplied by the
inlets with such regulated amount of air as is necessary for the better combustion
of the heated gases. These gases are then passed into the combustion chamber or
chambers E, where an additional regulated amount of air may, if required, be
admitted. In the air chamber or chambers F, and in the combustion chamber or
chambers E, the gases originally produced in the furnace or furnace chambers A,
undergo secondary or more complete combustion, and attain a much greater degree
of heat than when they left the furnace or furnace chambers A, the combustion
being so perfect that little or no carbonic oxide is observable at the exit of the
flues. At the same time a much less quantity of excess air over the theoretical
amount required for combustion is admitted than is usual in firing boilers in the
ordinary way.
The fuller opening of the air inlets f simultaneously with the opening of the
furnace doors, when the latter are opened to supply fresh fuel or to remove clinkers,
permits of the chimney draught acting but little upon the furnace chambers A
during that time, and so draws but little additional air through the furnace, the
chimney, draught being mainly satisfied with the extra amount of air supplied
for the time being through the air inlets f, the consequence being that even when
adding fresh fuel or clinkering, little or no smoke is observable at the chimney.
Having now particularly. described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is :-
1. A furnace, applicable to steam boilers, constructed with interior furnace
chamber or chambers to receive the fuel, provided with outlet openings preferably

page_text: in the sides, through which the products of combustion pass to an air chamber or
chambers, placed above or around the furnace chambers, and provided with air
inlet openings with valves or shutters, which are caused to open when the furnace
doors are opened to prevent a rush of air through the furnace chambers, and a
combustion chamber or chambers in which secondary or more complete combustion
takes place, located between the air chamber and flue of the boiler, substantially as
described.
2. In a furnace for steam boilers the combination of interior furnace chamber
or chambers A to receive the fuel, provided with side openings G and passages H
through which the products of combustion pass into the air chamber or chambers F,
placed above or around the furnace, into which a regulated amount of
air is admitted, regulating doors or valves M connected to the furnace
doors E, which are opened simultaneously therewith to prevent an inrush of
air into the furnace chambers A when the furnace doors are opened, and a com-
bustion chamber E into which all the heated gases and products of combustion
along with the admitted air are passed, and in which secondary or more complete
combustion is effected, substantially as described.
3. A furnace for steam boilers constructed and arranged substantially as described
and shown.
Dated s
Two day
aquaMONT TO
HOST
WM. P. THOMPSON & Co.,
Manchester, Liverpool and London, Patent Agents.