Improvements relating to the Firing of Steam Boilers, and Dealing with the Products of Combustion.
Year: 1890

page_text: Date of Application, 29th Dec., 1890
Complete Specification Left, 29th Sept., 1891-Accepted, 7th Nov., 1891
PROVISIONAL SPECIFICATION.
Improvements relating to the Firing of Steam Boilers, and Dealing
with the Products of Combustion.
I, PETER LUCAS, of Ditchingham Street, Sheffield, in the County of York,
Furnace Builder, do hereby declare the nature of my invention to be as follows:-
This invention to the construction of the furnaces of steam boilers, and.to,other
parts and appliances connected with such furnaces, and to the method of dealing
with, and utilizing the products of combustion from the said furnaces..to the best
advantage for the rapid generation of steam.
It consists briefly of improvements relating to the supply of fuel to the fire; to
the construction of the furnace or fire space; to the arrangement of a regenerator
in the flue of the boiler; and to the supply of air to promote combustion.in.the
furnace, and also for the combustion of the gases after leaving: the regenerator.
In the application of my invention to a single flue boiler, for example, 1 prefer
to dispense with the usual fire bars (although I do not debar myself from the use
of them) and I support a raised pipe (or more than one if desirable,,extending
from the front of the boiler, to the bridge or thereabouts; the pipe is provided
with a series of holes or nozzles in its sides, and the front. end is connected, with a
steam jet, so that steam and air can be blown into the fuel from each side of the
pipe.
The top of the pipe is protected from the action of the fire by a covering of fire
bricks, and upon and around the said pipe or pipes, the fuel is placed..and
consumed.
The fuel is supplied to the furnace by means of a hopper fitted with sliding or
swing doors, and arranged to shoot the fuel upon the fire, and a door is also
provided to rake the fire, and withdraw the refuse, but the front of the furnace.can
be perfectly closed against the admission of air, except through.the.blast pipe. I
may however if found desirable dispense with the front feed hoppers.as described,
and make one.or more vertical fuel holes from the, crown of the boiler, through,the
upper water space and opening over the furnace.
Past the bridge which may be of ordinary construction I build a regenerator,
preferably consisting of open brickwork so arranged in sinuous passages that the
flame and gases will take an indirect course, and be delayed in their passage.to.the
far end of the flue.
At the end of the flue I construct a door or valve that closes the flue..to any
desired extent, by means of levers and conveniently arranged for the attendant.to
operate. From this point the flue is by preference returned under the boiler,to the
front, where it is divided, each branch passing down.opposite sides of boiler to the
chimney stack.
Just beyond the door or valve beforementioned is the mouth of an air supply
chamber or conduit which I prefer to carry under the flue to the front, of, boiler, or
may use a pipe passing down the interior of the flue,, and at the front end of this
pipe or conduit, I fix a door by which the admission of air can be:regulated, or
shut off altogether.
When the air so admitted and heated in its passage, emerges from the mouth of
the conduit and meets the volume of gases passing from the generator through the
door or valve, it is ignited, and the flame so formed passes through the- return
boiler flues, the products of combustion being thus utilised to their fullest extent.
Dated the 24th day of December 1890.
ROBT. F. DRURY, Fel.. Inst. P.A.,
Bank Buildings, George Street, Sheffield, Agent for Applicant,

page_text: COMPLETE SPECIFICATION.
Improvements relating to the Firing of Steam Boilers, and Dealing
with the Products of Combustion.
I, PETER LUCAS, of Ditchingham Street Sheffield in the County of York
Furnace Builder 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 the construction of the furnaces of steam-boilers, and
to other parts and appliances connected with such furnaces, and to the method of
dealing with and utilizing the products of combustion from the said furnaces to the
best advantage for the rapid generation of steam.
It consists briefly of improvements relating to the supply of fuel to the fire; to
the construction of the furnace or fire-space; to the arrangement of a regenerator
in the flue of a boiler, and to the supply of air to promote combustion in the
furnace, and also for the combustion of the gases after leaving the regenerator.
And in order that my invention may be clearly understood I have annexed a
sheet of drawings in which my improvements are shown as applied to a single flued
boiler, for example.
Fig. 1, is a longitudinal section of a single flue boiler, and a portion of its brick-
work setting.
Fig. 2, is an elevation of the front of the same boiler.
In carrying my improvements into effect as shown, I prefer to dispense with the
ordinary fire-bars (but may use them if desirable,) and support a raised pipe or air
conduit A, or more than one if desirable, extending from the front of the boiler to
the bridge B, or thereabouts. This pipe or conduit A, is provided with a series of
holes or nozzles C, down each side, and the front end is connected with one or more
steam jets D, constructed so that air and steam can be blown into the pipe and
issue from the holes or nozzles into the fuel on each side of the said pipe or
conduit.
Water may be supplied into the interior of the pipe and be carried away by an
overflow, or the pipe may have a jacket to receive a constant supply of cold water
to prevent burning, or to counteract as much as possible the action of the fire;
this is not shown as it would complicate the drawings, and obviously can be carried
out in many ways.
The fuel being placed both above and on each side of the pipe or conduit I find
it in practice advisable to further protect the top by a covering of firebricks E, and
firebricks may also be laid to form a floor upon the bottom of the flue.
The fuel is supplied to the furnace through a hopper F, fitted with sliding (or
swing) doors G, and H, and is arranged to shoot the fuel upon the fire, there is
also a door I, provided through which the fire may be raked or stirred, and the
refuse withdrawn; but the front of the furnace is when in use, perfectly closed
against the admission of air, except that forced through the holes or nozzles of the
pipe or air conduit A.
An alternative plan of supplying the fuel, is to dispense with the hopper before-
mentioned, and construct one or more vertical fuel tubes or shoots from the crown
of the boiler, through the upper water space, and opening into the furnace; these
fuel tubes would be provided with covers to close the aperture when not in use.
66
At any suitable distance past the bridge B (which may be of ordinary con-
struction) I build a regenerator "K, preferably of firebricks, arranged so as to
form sinuous passages, or in such other manner as to baffle or retard the passage of
the flame and gaseous products of combustion in their passage to the far end of
the flue.
At the end of the flue I construct a door or valve L, in connection with a hand
lever M, or other convenient means whereby the said door or valve L, may be
partially or entirely closed by the attendant.

page_text: From this point the flue is constructed by brickwork and is preferably returned
nder the boiler to the front where it is divided, each branch passing down
pposite sides of the boiler to the chimney stack, but this arrangement forms no
art of the invention.
Just beyond the door or valve L, I arrange the mouth of an air-supply
hamber N, which is carried under the flue to the front of boiler (or as an
ternative I may carry a pipe down the interior of the brick flue) and at the
ont end of this air supply chamber N, (or the pipe as the case may be) I
xa door P, by which the admission of air can be regulated or be shut off
Itogether.
The air so admitted, is heated during its passage from the front to the back, and
merges from the mouth of chamber N, meeting the volume of gases as they pass
om the regenerator through the door or valve L; the mixture being ignited, the
ame so produced passes through the return boiler flues, and the products of com-
ustion are thus utilised to their fullest extent.
As a modification of the above described method or system, I may dispense with
e regenerator, and in combination with the closed fire, and furnace constructed
s before described, I may bring the air in a conduit from the mouth of the air-
upply chamber before described, down the boiler flue to the bridge B, and either
dmit it into the ordinary split bridge or in any other way cause it to meet the
ases from the furnace at the bridge.
Having now particularly described and ascertained the nature of my said inven-
on and in what manner the same is or may be carried into practice, I declare
hat what I claim is :-
1 In connection with a steam boiler;
(a) Forming the furnace into a close fire, and feeding it with fuel through a
hopper F, or through special supply tubes passing through the crown of the
flue,
(b) With one or more air conduits A extending from the front to the back or
thereabouts of the furnace, provided with holes or nozzles through which
air is forced into the ignited fuel,
(c) In combination with a regenerator K, built in the flue of the boiler, past
the bridge, a valve L, to regulate the passage of the gases at the end of the
flue, and
(d) An air chamber N having its mouth or exit near the valve L, and provided
with a regulator or door P°; all substantially as hereinbefore described and
as shown.
2-Constructing the furnace of a boiler as a close fire, with one or more blast
ipes A, extending from the front towards the bridge B, and provided with holes
r nozzles C, air being preferably supplied by means of steam jets D, and fuel by
eans of a hopper F, or by vertical tubes through the crown of the flue; in
ombination with a supply of air conveyed by the air chamber N, or by equivalent
beans either into a double or hollow bridge, or close to the bridge so as to meet
he gases from the fire and cause their more perfect combustion, substantially as
ereinbefore described.
3-As a system of "firing" in steam boilers, the combination of a close fire fed
ith air to promote combustion, through one or more blast pipes, with an air
apply having means to regulate the amount of air admitted, and preferably
arried under or through the built flue, and having its mouth at the end or in the
terior of the boiler flue, to meet the products of combustion, substantially as
ereinbefore described.
ו
1
501
a
ROBT. F. DRURY, Fel. Inst. P.A.,
Bank Buildings, George Street, Sheffield, Agent for Applicant.