IMPROVEMENTS IN FURNACES SPECIALLY ADAPTED TO THE GENERATION OF STEAM FOR MOTIVE POWER, BUT APPLICABLE TO FURNACES FOR ATHED PHDDASKS
Year: 1857

page_text: LETTERS PATENT to William Edward' Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Civil Engineer, for
the Invention of "IMPROVEMENTS IN FURNACES SPECIALLY ADAPTED TO THE
GENERATION OF STEAM FOR MOTIVE POWER, BUT APPLICABLE TO FURNACES FOR
ATHED PHDDASKS " & communication
PROVISIONAL SPECIFICATION left by the said William Edward Newton
at the Office of the Commissioners of Patents, with his Petition, on the
12th May 1857.
I, WILLIAM EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane,
in the County of Middlesex, Civil Engineer, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN FURNACES SPECIALLY ADAPTED, TO THE
GENERATION OF STEAM FOR MOTIVE POWER, BUT APPLICABLE TO FURNACES FOR OTHER
PURPOSES," to be as follows:--
The principal objects of the present Invention are to economise fuel in the
generation of steam for motive power, by burning most of the combustible
matter that usually escapes in the smoke.; to diminish the quantity of the
smoke, and thereby lessen its capacity for carrying off heat when it escapes
from the furnace; and to quench the sparks and prevent their escape.
These objects are accomplished by burning the fuel in a close furnace with
supply of fresh air forced in, and regulated by means of a pump, fan, or
other suitable contrivance,for, establishing through the furnace,above the fuel
on the grate, and through the flues of the boiler, a forced circulation of the
gaseous products of combustion, in combination with a regular admixture
of fresh air with, and a reheating of these gases until they are thoroughly
LD 077

page_text: oxidated, and have transferred most of the heat which they evolve during the
process of oxidation to the water in the boiler; after which they are so reduced
in bulk and increased in weight (the residuum being mainly carbonic acid),as
to settle by their own gravity into a receptacle in the bottom of a part of the
furnace, termed the smoke box, whence they escape through a small orifice
The sparks also collect in this receptacle, where they are at once quenched
by the carbonic acid in which they are immersed. By establishing this cir-
culation and combustion of the gases above the solid fuel on the grate, and
maintaining a constant stream of fresh air flowing beneath the grate into the
fire, the solid fuel is kept burning briskly, instead of the smouldering,deadened
and slow combustion which has resulted from all attempts to burn the smoke
by passing it through the solid fuel in a close furnace. By this means the
advantages of the open furnace, in burning the fuel briskly on the grate,
are combined with the advantages of the close furnace in consuming the
smoke, and the disadvantages of both classes of furnaces, as heretofore con
structed, are avoided:
A modification of the above may be produced by causing the gaseous
products of combustion to be exhausted from the flues, and mixed in the smoke
box with a suitable quantity of fresh air, and then the mixed gases may
be returned to the ash-pit.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Edward Newton in the Great Seal Patent Office
on the 12th November 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the County
of Middlesex, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twefth day of May, in the year of our Lord One
thousand eight hundred and fifty-seven, in the twentieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William Edward Newton, Her special license that I,the said William Edward
Newton, my executors, administrators, and assigns, or such others as I, the
said William Edward Newton, my executors, administrators, and assigns,
should at any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed,should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great Britain

page_text: commu-
and Ireland, the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN FURNACES SPECIALLY ADAPTED TO THE GENERATION OF STRAM FOR MOTIVE
POWER, BUT APPLICABLE TO FURNACES FOR OTHER PURPOSES," being a
nication from abroad; upon the condition (amongst others) that I, the said
William Edward Newton, by an instrument in writing under my hand and
seal, should particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office within six calendar months next
and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Edward Newton, do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the Drawings hereunto annexed,
and to the letters and figures marked thereon (that is to say):
This Invention of improvements in furnaces, and which has been commu-
nicated to me from abroad, is described by my foreign correspondent as being
specially to the generation of steam for engines for obtaining motive power;
but it is also applicable to furnaces for other purposes.
In the accompanying Drawings, Fig. 1 represents an elevation of the
side of a tubular steam boiler and furnace for a locomotive engine, and
embraces the improvements. Fig. 2 represents a vertical longitudinal section
of the same; Fig. 3 represents an elevation of the rear end of the boiler;
Fig. 4 represents a transverse section at the line x, x, of Fig. 2; and Fig. 5
represents a transverse section at the line X, X, of Fig 2..
The principal objects of the Invention are, to economise fuel in the
generation of steam for motive power, by burning or consuming a considerable
portion of the combustible matter that usually escapes in the smoke, thereby
diminishing the quantity of the smoke,and consequently lessening its capacity
for carrying off heat when it escapes from the furnace, and to quench the sparks
and prevent their escape.
These objects are accomplished by burning the fuel in a close furnace with
a supply of fresh air forced in by means of a pump, fan, or other suitable
contrivance, for establishing through the furnace, above the fuel on the grate,
and through the fluesof the boiler, a forced circulation of the gaseous products
of combustion, in combination with a regular admixture of fresh air with, and
a reheating of these gases until they are thoroughly oxidated, and have
transferred most of the heat, which theyevolve during the processof oxidation,
to the water in the boiler; after which they are so reduced in bulk and
increased in weight (the resiiuum being mainly carbonic acid), as to settle by

page_text: their own gravity into a receptacle in the bottom of a part of the furnace,
termed the smoke box, whence they escape through a small orifice. The
sparks also collect in this receptacle, where they are at once quenched by the
carbonic acid in which they are immersed.
By establishing this circulation and combustion of the gases above the solid
fuel on the grate, and maintaining a constant stream of fresh air flowing
beneath the grate into the fire, the solid fuel is kept burning briskly, instead
of the smouldering, deadened, and slowcombustion which has resulted from all
attempts to burn the smoke by passing it through the solid fuel in a close
furnace. Bythis means the advantages of the open furnace, in burning the fuel
briskly on the grate, are combined with the advantages of the close furnace in
consuming the smoke, and the disadvantages of both classes of furnaces,
as heretofore constructed, are avoided.
A modification of the above may be produced by causing the gaseous
productsof combustion to be exhausted from the flues,and mixed in the smoke
box with a suitable quantity of fresh air, and then the mixed gases may
be returned to the ash-pit.
By reference to the accompanying Drawings, which show the application of
the Invention to what is known as a "tubular" or "locomotive" boiler and
furnace, the precise nature of the Invention will more fully appear :-
This boiler consists of a cylindrical shell A, provided with the usual steam
domes a, a, and is connected at one end with a fire chamber B, and at the
other with a smoke box C. The fire chamber B is provided with an air-tight
ash-pit 6 and a valvular feeding hopper and tube 1), by which the fuel can be
supplied to the furnace from time to time, as required, without permitting the
air to enter the furnace or gas to escape from it. The fire chamber B is
further provided with suitable air-tight doors, whereby access may be obtained
to its interior both above and below the grate bars.
Instead of having but one tube sheet, and that placed at the oackof the fire
box, as in the ordinary horizontal tubular boiler, this fire box has one tube
sheet dat its back, and another eat its top; the back sheet d receives
a series of straight tubes E, that conduct the gases and heat from the fire
chamber into the smoke chamber C, and the top sheet e receives the ends of a
series of tubes F, that return the soot and lighter portion of the gases to the
fire chamber to be mixed with air and passed over the fire again, so as to con-
tinue the burning of such parts of them as are combustible, but which had
passed through the fire chamber without being burned.
These two series of tubes, at their ends which terminate in the smoke
amber, can only communicate through a rotary fan or pump H, or other

page_text: analogous contrivance, as the return flues F open into the case of the fan H,
and the direct flues E open into the smoke chamber C, so that the gases and
soot, in passing from the direct flues E,to the return flues F, must passthrough
the fan case, which they enter by the usual central openings i.
Within the smoke chamber on each side of the fan case, is placed a dia-
phragm or plate L, extending backward from the tube sheet above the lower
flues, about two-thirds of the way across the smoke box. These diaphragms
or plates incline downward and backward so as to deflect the sparks and
gases (as they enter) towards the bottom of the chamber, and by compelling
the gases on their passage to the fan to take a long circuit in the wide space
of the smoke box, sufficient time will be allowed for the heavier portions of
the gases, which are saturated with oxygen, to settle by reason of their gravity
to the bottom of the smoke box, and thence run out through an opening h
provided for the purpose. By means of the diaphragms L, the ashes and
cinders are in like manner precipitated to the bottom of the smoke box C.
The fan H is constructed like a common fan blower, and is placed in a suit-
able case, which occupies nearly the whole length and about half the depth
and width of the smoke box. The fan case terminates where it meets the
tube sheet f, the whole of the front of the case being open so as to com-
municate freely with the return tubes F. The front portion of this case
spreads out to include such of the return flues as are not directly in front of
the fan.
The axle m of this fan extends through both sides of the smoke box, and is
supported in bearings on the outside, where they are not liable to be affected
by the ashes and heat, which would quickly destroy bearings placed on the
inside of the smoke box. On each of the projecting ends of the axle m of
the gas fan H, an air fan I of smaller dimensions is placed, as shewn at Fig. 4.
The case of each of these air fans I communicates with a pipe or with pipes,
that communicate with the fire chamber above and below the grate, to
supply the air necessary for the combustion of the fuel.
The principal
opening for the admission of air into these fans is on the outside of each,
nearits axis,but a smaller opening is made in each case on the side adjacent to
the smoke box, to cause a draught of air to enter. round the shaft, to help
to keep it cool. The apertures in the sides of the smoke box, through which
the shaft of the fans pass, may each be fitted with a tube, in which a series
of diaphragms may be fitted to surround the shaft like collars, leaving spaces
between to permit the passage of gas ashes, &c.
The top of the smoke box is fitted with a short pipe K, with a lid on its
upper extremity. This pipe is opened to create a draught while the fire is

page_text: being kindled, and until sufficient steam has been generated to work the fans.
A door in the ash-pit is of course opened at the same time to admit air to
the fuel. When sufficient steam is raised to work the fans, the doors in the
pipe and ash-pit are both closed. The spent gases escape from the bottom
of the smoke chamber through a pipe turned upwards at its outer end, a
little more than its own diameter, so that it allows the heavy gases to flow
out freely without admitting atmospheric air. The fans are worked by a
belt put in motion by the engine, for which the boiler generates steam.
As soon as the fire has been kindled, and has generated steam enough to
work the engine and turn the air and gas fans H and I, the draught doors are
closed, and the air for the support of the combustion is forced into the furnace
through the pipesJ. The comparatively cool return gases and soot descending
from the tubes in the top of the fire chamber are heated by mixing with
the hot gases which are rising from the fuel, so that they readily inflame on
coming in contact with the jets of air injected above the fuel, and while in-
flamed they pass through the tubes E into the smoke box C. On their passage
through these tubes E, the gases impart to them a portion of their heat, which
they in turn impart to the water in contact with them. Such portion of the
gas, as has been thus cooled and is saturated with oxygen, becomes so heavy
that it readily falls by reason of its gravity to the bottom of the smoke box,
and runs out at the waste pipe h, while the lighter, hotter, and but partially
oxidated gases are drawn by the fan into the case, and forced through the
return tubes F back into the fire chamber, to be again heated and mixed with
air and inflamed to complete their combustion, when they repass to the smoke
chamber, where such portions of them, as are sufficientlycooled and saturated
with oxygen, settle to the bottom of the chamber and run off, while the re-
mainder is returned by the fan H and flues F to the fire chamber B, again to
undergo the process of heating andmixingwith air; whichprocess is repeated
until the whole of the combustible portion of the smoke is utilized.
The motion of the fan H, while producing this circulation, creates a partial
vacuum in the smoke box C, which extends to the lower tubes E, and causes
them to draw the gases from the fire box B, while at the same time a degree
of pressure, corresponding to the vacuum,isproduced in front of thefan, which
pressure drives the gases, drawn from the smoke chamber by the fan, through
the return tubes F to the fire chamber, on their passage to which the gases
impart a further portion of their heat to the tubes, which transfer it to the
water surrounding them. During this operation of the gas fan H within the
furnace, the air fans I without are forcing air into the fire chamber above the
fuel, so as to burn the gases, and also below the fuel to keep it burning

page_text: brightly. By means of hand valves in the air pipes the quantity of air dis-
charged into the furnace can be regulated at will; or, the valves may be
regulated by the governor of the engine, as may be deemed best. So also the
orifice h for the escape of the gases may be enlarged or diminished by means of
a suitable valve or register. The pressure produced within the furnace by the
influx of air accelerates the discharge of spent gases through the waste pipe h.
The portion of these gases which is lowest, and consequently nearest the dis-
charge pipe, is pressed upon and gradually displaced by that portion imme-
diately above. This pressure of one portion of the spent gases on the other
forces it,out much faster than it would be discharged by the action of gravity
alone, which would not carry it off through an aperture sufficiently small to
prevent the entrance of air, or the escape of combustible gas.
By this process the soot or smoke is effectually prevented from escaping,
and at the same time is utilized by burning it as fuel. The waste gases are
much diminished in volume by the thorough oxida tion which they undergo
and the heat carried out of the furnace by them is correspondingly diminished
and in this way an important saving is effected, not only without expense, but
by the burning of combustible matter, which effects another saving still more
important, by adding to the amount of heat-generating material utilized from
a given quantity of fuel. When the sparks fall to the bottom of the smoke
box C, they are immersed in an atmosphere chiefly of carbonic acid, which
will not support combustion, and they are consequently quenched at once, and
may be withdrawn.at suitable intervals through a door, and again fed into
the fire-box with fresh fuel, by which means they are also utilized.
For the purpose of still more effectually preventing the heat from being
carried off by the waste gases, the Inventor proposes to heat the feed water
for the boiler by passing it through pipes placed in the lower part of the
smoke box.
Figures 6, 7, 8, and 9 represent a modification of the above, the principal
difference being, that gases are mixed with air in the smoke box and are
returned to the fire box in a mingled state.
Fig. 6 represents a side elevation of a single flue steam boiler, arranged and
constructed for the purpose of carrying out this modification; Fig.7 represents
a horizontal longitudinal section through the same; Fig. 8 represents a trans-
verse section through the smoke box at the line X, X, of Fig. 6; and Fig. 9
represents a transverse section through the furnace, at the line o, o, of Fig. 6.
The principle of burning the fuel in a close furnace, through which a
regular current of fresh air mingled with the gaseous products of combustion
is constantly flowing, is the same in both cases.

page_text: the
In Figures 6, 7, 8, and 9, the current is established by connecting the
furnace and smoke box by two flues or series of flues, through one of which
gasses can pass from the furnace to the smoke box, and through the other
return from the smoke box to the furnace, a fan or other suitable pump being
arranged in the circuit to maintain the current at a proper velocity, as in the
former instance.
As the gases enter the smoke box, they are mingled with fresh air; thence
passing into the fan case D, they are forced by the fan F through the return
flue back into the furnace, where they are again inflamed, and pass through
the flues of the boiler into the smoke box to he again mingled with air. By
this operation the gaseous products are alternately mixed with fresh air and
reheated until they are thoroughly oxydated, transferring most of the heat,
which they evolve during the process of oxydation, to the water within the
boiler; after which they are so much reduced in bulk and increased in weight,
as to settle by their own gravity to the bottom of the smoke box, through
which they escape by a small opening provided for the purpose. The sparks
also settle to the bottom of this receptacle, and are extinguished by the burnt
and uninflammable gas in which they are immersed.
In the accompanying Drawing, the boiler, to which the improvement is
applied, consists of a cylindrical shell A and flue B, connected at one end
with a fire chamber C, and at the other with a smoke box D. The fire
chamber Cis provided with suitable air-tight doors E, E, Fig. 6, both above
and below the grate bars. The upper one E is used to supply the furnace
with fuel from time to time as required, and the lower one E' is to give access
to the ash-pit. A valvular feeding hopper may be used, instead of the
upper
door, to supply the furnace with fuel, as in Figures 1 and 2. The flue B forms
a communication between the fire chamber and smoke box, through which the
gaseous products of combustion pass with the sparks from the furnace to the
smoke box.
A fan F, constructed like the ordinary fan blower, is placed on one side of
the smoke box, with sufficient space around the fan case for the gases to enter
it freely. A pipe G, on the outside of the boiler (one end of which enters the
furnace beneath the grate bars, and the other passes through the smoke box
and terminates in the fan case), forms a communication between the smoke
box D and the furnace C through the fan case. This pipe after leaving the
fan case may be forked, one branch entering the fire box below the grate
bars, and the other entering the fire box just above the fuel on the grate, by
which means the unconsumed gases would enter the fire box both above and
below the grate bars.

page_text: Under the arrangement of the fan here adopted, its axle extends through
the sides of the smoke box, as shewn in Figures 7 and 8, and is supported in
suitable bearings H,formed in the sides of the box. On one of the projecting
ends of the axle is a pulley I, by which motion is given to the fan in the
usual manner. An air pipe J, whose outer end is trumpet-mouthed, enters
the upper part of the smoke box to supply the fresh air necessary for the
combustion of the fuel.
On the top of the smoke box there is a chimney, which is fitted with a
valve K; to be opened to create a draft while the fire is being kindled, and
also during the time fuel is being fed into the furnace, that the gases may
not he blown out at the furnace door. In order to avoid opening the valve K
in the chimney during the feeding of the furnace, a valve may be placed in
the return pipe leading from the fan, which the opening of the furnace door
will close; or, if the valvular feeding hopper is used, the opening of this valve
K while feeding will be unnecessary.
As soon as the fire has been well kindled, the furnace doors and chimney
valve are closed; the valve L, Fig. 7, of the air pipe J is opened, and the fan
put in motion. Air for the support of combustion is drawn into the smoke
box and mingled with the gases, and while thus mingled the two are forced
by the fan into the furnace beneath the grate bars, and as they pass through
the fuel lying on the grate bars, a portion of the oxygen of the air mixed
with the return gases is taken up by this fuel, and thus its combustion is
maintained, while the remainder of the oxygen of the air combines with the
gases as they are heated in passing through the furnace to complete their
combustion.
The motion of the fan, while producing this circulation; creates a partial
vacuum in the smoke box, which draws the gases from the fire box,and causes
the fresh air to rush in through the supply pipe. Owing to the entrance of
the air pipe in the upper part of the smoke box, the fresh air flows down
among and becomes intimately mixed with the gases before they enter the fan,
and the agitation produced by the rotation of the fan blends them still more.
intimately..
:
When these gases, intimately mingled with fresh air, pass through the
interstices between the pieces of solid fuel on the grate bars, a portion of the
oxygen, derived from the fresh air, goes to the support of the combustion of the
solid fuel,causing it to burn freely, while the remainder is graduaily combined
with the gases, as already mentioned.
It is obvious that the arrangement of the several parts, which constitute the

page_text: improved system above described, of circulating and reheating gases until their
oxidation is complete, may be modified to adapt them to different boilers,
and the varied circumstances in which it is necessary to generate steam for
motive power and other purposes; but I do not deem it necessary to enter
into details of such modifications, as they will be sufficiently obvious to
competent engineers.
Having thus describedthe improvements which have beencommunicated to
me from abroad, as aforesaid, I claim,-
First, the arrangement of the fire and the smoke chambers, the direct and
the return flues, the gas and the air pumps, the pipes to supply air above and
below the grate, and the waste pipe for the spent gases.
Second, the diaphragms or plates to direct the gases downward and back-
ward, as they enter the smoke chamber, to facilitate the precipitation of the
sparks and thoroughly oxidated gases from those gases which are but partially
burnt, and require for the completion of their combustion to be returned to
the fire chamber.
Third, the arrangement, at or near the bottom of the smoke chamber, of an
open orifice for the free and constant escape of the waste gases, as herein set
forth.
Fourth, the arrangement of the gas and air pumps, fans, or other analogous
contrivances upon a common shaft, whereby the mechanism is simplified, and
the journals of the shaft kept cool, as herein set forth.
Lastly, I claim the mode herein described, or any mere modification thereof,
for thoroughly mixing the combustible gases with air before they enter the
furnace to be reinflamed or consumed.
In witness whereof, I, the said William Edward Newton, have hereunto
set my hand and seal, the Twelfth day of November, in the year of
our Lord One thousand eight hundred and fifty-seven.
Witness,
• J. W. MOFFATT,
66, Chancery Lane.
W. E. NEWTON. (L.S.)