IMPROVEMENTS IN THE METHOD OF UTILIZING the Heat OF FURNACES FOR BOILERS GENE- RATING STEAM AND FOR OTHER PURPOSES WHERE HEAT IS REQUIRED
Year: 1878

page_text: •
LETTERS PATENT to William Morgan-Brown, of the Firm of Brandon and
Morgan-Brown, Engineers and Patent Agents, of 38, Southampton Buildings,
London, and 1, Rue Laffitte, Paris, for the Invention of "IMPROVEMENTS
IN THE METHOD OF UTILIZING the Heat OF FURNACES FOR BOILERS GENE-
RATING STEAM AND FOR OTHER PURPOSES WHERE HEAT IS REQUIRED." A
communication from abroad by Obadiah Marland, of Boston, Massachusetts,
United States of America.
J
Scaled the 12th November 1878, and dated the 26th June 1878.
PROVISIONAL SPECIFICATION left by the said William Morgan-Brown at
the Office of the Commissioners of Patents on the 26th June 1878.
WILLIAM MORGAN-BROWN, of the Firm of Brandon and Morgan-Brown, Engineers
and Patent Agents, of 38, Southampton Buildings, London, and 1, Rue Laffitte,
Paris. "IMPROVEMENTS IN THE METHOD OF UTILIZING THE HEAT OF FURNACES
FOR BOILERS GENERATING STEAM AND FOR OTHER PURPOSES WHERE HEAT IS
REQUIRED." [A communication from abroad by Obadiah Marland, of Boston, Mas-
sachusetts, United States of America.]
"
This Invention of improvement in the method of utilizing the heat of furnaces
for boilers generating steam and for other purposes where heat is required is
designed to abstract and utilize the heat escaping in the volatile products of coin-
bustion of fuel in such manner as to reduce the temperature of the escaping volatile
products of combustion to an approximation with the temperature of the atmosphere,
thus economizing fuel, and to apply the heat so abstracted to the current of ordinary
atmosphere coming to the furnace, so as to improve the combustion of the solid fuel
and of the gases escaping therefrom.
In this Invention mechanical power is applied to draw the volatile products of
combustion from the furnace and furnace passages and chambers therewith con-
nected, the atmosphere passing by operation of the law of nature to supply the place
of that which has been abstracted from the furnace, the atmosphere being drawn
through flues, pipes, or passages into space, with other flues, pipes, or passages

page_text: through which the escaping volatile products of combustion are drawn, said flues,
pipes, or passages being made of sheets of metal or other good conducting material,
and so formed and shaped as to give large conducting surfaces as compared with the
cubic capacity of the flues.
While this Invention is applicable to all furnaces in which fuel is consumed for
generation of heat to be applied to any purpose, it will be herein explained as applied
to a furnace connected with the boiler used for generating steam.
The value of an artificial draught, as compared with the draught kept up by
combustion through the instrumentality of a chimney, is known to engineers, and is
variously stated by different authorities. In two instances decided by "Veclet,"
the gain given as ascertained was in one case about as 6 to 1, and in the other as
17 to one, and to this gain this Invention adds the gain due to the abstraction and
utilization of a very large per-centage of the heat contained in the escaping
volatile products of combustion, after they have passed the last point, where the
heat contained therein is applicable to any useful purpose, coupled with the gain to
be had from the introduction of highly heated pure air into the escaping products of
combustion at desirable points in the space occupied by them, until very nearly all
that is combustible therein is consumed; and made to give up the heat consequent
upon such combustion.
This Invention consists in the combination of a furnace and abstracter with a
mechanical exhauster.
Also, in the combination of an air-forcing device, furnace abstracter, and a
mechanical exhauster.
Also, in an abstracter composed of plates or sheets of conducting material formed
into chambers alternately arranged for passage of air and volatile products of com-
bustion and removable filling pieces, the abstracter being combined with the dis-
charging end of a furnace and with the furnace space over the grate bars.
Also, in an exhauster and an abstracter with passages formed and arranged in
combination with the discharging end of a furnace, and by means of a suitable
passage with the space under the grate bars.
Also, in an exhauster and an abstracter formed in combination with a discharging
end of a furnace, and by means of a suitable passage with the combustion chamber
at or beyond the first bridge wall.
Also, in an extracter composed of metal plates or sheets placed with relation each
to the other to form chambers, and of removal filling pieces to permit the abstracter
to be cleaned.
This Invention is further designed to heat incoming atmosphere to a much higher
degree than can be effected by the escaping products of combustion alone, so that
the chemical union of the highly heated oxigen entering the furnace with the carbon
fuel will be quickened and perfected. This part of the Invention may be used alone
or in combination with the first part, as circumstances may require; and the Inven-
tion therefore further consists in a heating chamber or chambers located within the
combustion chamber and above the grate bars of a furnace, and arranged to receive
air to heat the same and to deliver it highly heated in fine streams to mingle with
and perfect the combustion of the gases escaping from the fuel.
Also, in combination with a furnace provided with chambers located within the
combustion chamber, of an abstracter and exhauster.
The combustion chamber above the grates has the boiler, as its crown or upper
boundry, the volatile products of combustion from the combustion chamber (which
in this case is the entire space under the boiler, including the rear "up-take")
escaping through the boiler tubes into the front smoke box.
Over the boiler setting is a device, which will herein be termed the abstracter,
its function being to allow the passage through one set of channels or passages
therein of pure air, so that the heat contained in the volatile products of combustion
passing through another set of channels or passages in the abstracter will be
absorbed through the division plates of the abstracter by the air going to support
-and improve the combustion of the fuel and of the gases liberated therefrom.

page_text: The arrangement of this abstracter in order to produce the best results is such as
to cause the outgoing gases to move in a direction contrary to the incoming air, the
latter entering near where the gases are escaping, and where consequently they are
coolest, and progressing toward the furnace, receiving constantly new increments of
heat.
There are two sets of passages in the abstracter, those conveying air and those
conveying gases from tho smoke box. The latter connect with an exhausting
device, the form of what is known as the "root blower;" but other forms of rotary
blowers or fans, or other devices for exhausting or for reducing pressure, would serve
the purpose.
The discharge from the exhausting device is through a conduit which, when
convenient or needed, may be coupled to a chimney.
In cases where in starting a fire to generate steam in the main boiler, no auxiliary
power is available for working the exhauster, a passage is provided to permit the
gases to pass off by their own lovity, a valve being arranged so as to make the
passage operative or inoperative at will. In such case, the air is shut off from the
passages so as not to cool the escaping gases, and the air is admitted under the
grates through the ash-pit door in the usual manner, until steam of sufficient
pressure is generated to work the motor which drives the exhauster, at which time
the motor being put in operation, the valve and the ash-pit door are closed, and air
is admitted to the passage to take up the heat existing in the gasos moving from
the furnace in the second passages.
The passages in the abstracter are made thin and flat so as to give large heating
and absorbing surfaces in proportion to their cubic capacity, and the whole assem-
blage of them is covered by a suitable non-conductor to prevent radiation of heat.
All of the first set of passages of the abstracter connect with an air pipe which
communicates with branch pipes, one of which having its controling valve, leads
one supply of heated air under the grates, another having its valve, admits air
directly into the furnace over the fuel, another having its valve, admits hot air
behind the first bridge wall, and another having its valve admits hot air behind
the second bridge wall into the space behind it, and into the rear up-take, there
completing combustion of the escaping gases. These bridge walls, with passages
arranged for emitting air in finely divided streams, may be as numerous as the
length of the furnace will allow; provisions are made for clearing out solid deposits
from between and beyond the bridge walls, and for peep holes for observing the
character of the combustion, while the valves afford means for regulating and con-
troling the character and rate of combustion.
The passages in the abstracter receiving only pure air to be licated, will not be
likely to become coated or obstructed with any deposit, as will the second passages
for the escaping gases. Both sets of passages can be cleared readily by removal of
a plate at the rear of the abstracter, and by removal of certain filling pieces.
In some cases, as in boilers for naval and marine use, and where on land large
power is located in confined space, and where usually small auxiliary or donkey
engines and boilers are kept in constant readiness for use, it may sometimes be
advisable to make use in connection with an exhauster of the waste gases of a
blower of any suitable form for forcing the pure air through the first set of passages
of the abstracter in re-inforcement of the exhauster, instead of simply allowing the
air to follow naturally the gases as removed by the exhauster.
In most cases, the use of the exhauster alone is preferable, as then the gases and
dust are not forced out of the furnace through crevices or through the firing and
ash-pit doors, when these are opened for the duties of the fireman, and when a
pressure device in combination is used for supplying air, it is preferable to regulate
its action, so as to cause the pressure in the furnace not to exceed that of the
atmosphere, except in cases of emergency.
In the use of the abstracter, the supply of a small surplus of air to the furnace
does not result in a material loss, inasmuch as the heat which it takes up in the

page_text: furnace and carries away from it, is given back to the air passing to the furnace
through the medium of the abstracter.
In locomotives, the exhauster and abstracter may be used in connection with the
furnace which preferably should have its combustion chamber made as large as is
practicable. In such cases the exhaust steam should be let freely off from the
cylinder to relieve the pistons from back pressure.
In one form of the Invention for heating the incoming products of combustion to
a high degree, air either in its natural condition or heated in its passage through
the abstracter before described, flows through a conveyer either above the fuel on
the grates, or both above and below, as may be determined by the position of the
valves, which are subject to the control of the engineman or of the stoker, but when
conveyed above the grates, it passes into a heating chamber or chambers, instead of
into the combustion chamber over the fuel, as is the common practice.
The heating chambers are located within the space which would be, if not so
occupied, combustion chamber, and as they are subjected to a very high temperature,
will preferably be made of refractory material, such as fire-clay. Of course, such
heating chambers will vary in form and dimensions with the various forms and
sizes of the furnaces with which they are combined. In one example, the lower
chamber rests on a fire-brick ring resting on the grates, and supports an upper
chamber. The air entering from the conveyer flows past the valve into a heating
chamber which is highly heated by the combustion of the fuel in the grates, and
after passing about the fire chamber, or nearly so, enters a chamber through
suitable openings, and passes back through said chamber, from which it flows at a
temperature nearly coincident with the tomperature of the combustion chamber in
fine streams through perforations, and mingling with the gases escaping from the
incandescent fuel, combustion of an intense and rapid character is the result, con-
sequent upon the affinity between highly heated oxygen and carbon in a gaseous or
finely comminuted form.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Morgan-Brown in the Great Seal Patent Office on the 18th
December 1878.
WILLIAM MORGAN-BROWN, of the Firm of Brandon and Morgan-Brown, Engineers
and Patent Agents, of 38, Southampton Buildings, London, and 1, Rue Laffitte,
Paris. "IMPROVEMENTS IN THE METHOD OF UTILIZING THE HEAT OF FURNACES
FOR BOILERS GENERATING STEAM AND FOR OTHER PURPOSES WHERE HEAT IS
REQUIRED." A communication from abroad by Obadiah Marland, of Boston, Massa-
chusetts, United States of America.
This Invention of improvements in the method of utilizing the heat of furnaces,
for boilers generating steam, and for other purposes where heat is required is
designed to abstract and utilize the heat escaping in the volatile products of com-
bustion of fuel in such manner as to reduce the temperature of the escaping volatile
products of combustion to an approximation with the temperature of the atmosphere,
thus economizing fuel, and to apply the heat so abstracted to the current of ordinary
atmosphere coming to the furnace, so as to improve the combustion of the solid fuel
and of the gases escaping therefrom.
In this Invention mechanical power is applied to draw the valatile products of
combustion from the furnace and furnace passages and chambers therewith connected,
the atmosphere passing by operation of the laws of naturo to supply the place of
that which has been abstracted from the furnace, the atmosphere being drawn
through flues, pipes, or passages interspaced with other flues, pipes, or passages,
through which the escaping volatile products of combustion are drawn; said flues,
pipes, or passages being made of sheets of metal or other good conducting material,
and so formed and shaped as to give large conducting surfaces as compared with the
cubic capacity of the flues.
While this Invention is applicable to all furnaces in which fuel is consumed for
generation of heat to be applied to any purpose, it will be heroin explained and
illustrated as applied to a furnace connected with the boiler used for generating
steam.
The value of an artificial draught as compared with a draught kept up by com-
bustion through the instrumentality of a chimney is known to engineers, and is
variously stated by different authorities. In two instances cited by "Peciet " the
gain given as ascertained was in one case about as six to one and in the other as
seventeen to one, and to this gain this Invention adds the gain due to the abstrac-
tion and utilization of a very large per-centage of the heat contained in the escaping
volatile products of combustion after they have passed the last point where the heat
contained therein is applicable to any useful purpose, coupled with the gain to be
had from the introduction of highly heated pure air into the escaping products of
combustion at desirable points in the space occupied by them until very neally all
that is combustible therein is consumed and made to give up the heat consequent
upon such combustion.
This Invention consists in the combination of a furnace and abstracter with a
mechanical exhauster, substantially such as described, to operate as and for-the-
purpose set forth.
Also, in the combination of an air-forcing device, furnace abstracter, and a
mechanical exhauster, substantially such as described, for the purpose specified.
Also, in an abstracter composed of plates or sheets of conducting material, formed
as described, into chambers alternately arranged for passage of air and volatile
products of combustion, and removeable filling pieces, the abstracter being combined
with the discharging end of a furnace, and with the furnace space over the
grate bars.
Also, in an exhauster and an abstracter with passages, formed and arranged as
described, in combination with the discharging end of a furnace, and by means of a
suitable passage with the space under the grate bars, for the purpose described.
•

page_text: Also, in an exhauster and an abstracter, formed and arranged as described, in
combination with the discharging end of a furnace, and by means of a suitable
passage with the combustion chamber at or beyond the first bridge wall, for the
purpose described.
Also, in an abstracter composed of metal plates or sheets placed with relation each
to the other as shown, to form chambers a, b, and of removeable filling pieces to
permit the abstracter to be cleaned, substantially as described.
This Invention is further designed to heat incoming atmosphere to a much higher
degree than can be effected by the escaping products of combustion alone, so that
the chemical union of the highly heated oxygen entering the furnace with the carbon
of the fuel will be quickened and perfected. This part of the Invention may be used
alone or in combination with the first part, as circumstances may require; and the
Invention therefore further consists in a heating chamber or chambers, substantially
such as herein-after described, located within the combustion chamber and above
the grate bars of a furnace, and arranged to receive air to heat the same, and to
deliver it highly heated in fine streams to mingle with and perfect the combustion
of the gases escaping from the fuel, substantially as herein-after described.
Also in the combination with a furnace provided with chambers e³ or g³, or both,
located within the combustion chamber of an abstracter and exhauster, to operate
substantially as described.
Of the Drawings showing an embodiment of this Invention as applied to a boiler
for generating steam, Figure 1 is a plan; Figure 2 is a side elevation; Figure 3 is
a front end elevation; Figure 4 is a horizontal section, taken on the line z, z,
Figure 2; Figure 5 is a cross vertical section, taken on the line y, y, Figure 1;
Figure 6 is a cross vertical section, taken on the line a, a, Figure 1; Figure 7 is a
longitudinal vertical section, taken on the line w, w, Figure 1; Figures 8, 9, and 10
are details, which will be specified beyond; and Figure 11 is a modification, to be
herein-after referred to.
v, Figures 5 and 7, shows the grate bars of a furnace which is set or made of
brickwork so as to support a horizontal tubular boiler, the walls being hollow, and
other well-known means of preventing loss of heat by radiation, being applied.
The combustion chamber above the grates has the boiler as its crown or upper
boundary, the volatile products of combustion from the combustion chamber (which
in this case is the entire space under the boiler, including the rear "up-take"),
escaping through the boiler tubes into the front smoke box.
Over the boiler setting is a device m², which will herein be termed the abstracter,
its function being to allow the passage through one set of channels or passages
therein of pure air, so that the heat contained in the volatile products of combustion
passing through another set of channels or passages in the abstracter will be absorbed
through the division plates of the abstracter by the air going to support and improve
the combustion of the fuel and of the gases liberated therefrom.
The arrangement of this abstracter m² in order to produce the best results is such
as to cause the outgoing gases to move in a direction contrary to the incoming air,
the latter entering near where the gases are escaping, and where consequently they are
coolest and progressing toward the furnace, receiving constantly new increments of
heat.
The passages marked a in the abstracter are those conveying air, and those
marked b are those conveying gases from the sinoke box c.
The passages b connect with the exhausting device d, which is shown in the
Drawings in the form of what is known as the "root blower," but other forms of
rotary blowers or fans, or other devices for exhausting or for reducing pressure
would serve the purpose.
The discharge from the exhausting device is through the conduit e, which when
convenient or needed may be coupled to a chimney.
In cases where in starting a fire to generate steam in the main boiler no auxiliary
power is available for working the exhauster da passage f is provided to permit
the gases to pass off by their own levity, a valve g being arranged so as to make

page_text: the passage operative or inoperative at will. In such case the air is shut off from
the passages a so as not to cool the escaping gases, and the air is admitted under
the grates through the ash-pit door in the usual manner until steam of sufficient
pressure is generated to work the motor which drives the exhauster, at which time
the motor being put in operation the valve g and the ash-pit door are closed, and
air is admitted to the passages a to take up the heat existing in the gases, moving
from the furnace in the passages b.
The passages a and b are made thin and flat so as to give large heating and
absorbing surfaces in proportion to their cubic capacity, and the whole assemblage
of them is covered by a suitable non-conductor to prevent radiation of heat.
Figure 8 shows a cross section of the abstracter; and Figure 9 is a detail in cross
section of a modification thereof.
All of the passages a connect with an air pipe h which communicates with branch
pipes, one of which, i, having its controling valve ', leads one supply of heated
air under the grates; another, j, having its valve j', admits air directly into the
furnace over the fuel; another, I, having its valve k, admits hot air behind the first
bridge wall a; and another, l, having its valve l, admits hot air behind the second
bridge wall a into the space behind it and into the rear up-take, there completing
combustion of the escaping gases. These bridge walls with passages arranged for
emitting air in finely divided streams may be as numerous as the length of the
furnace will allow, and there will be seen in the Drawings provisions for clearing
out solid deposits from between and beyond the bridge walls, and for peep holes for
observing the character of the combustion, while the valves i, j, k, l, afford means
for regulating and controling the character and rate of combustion.
The passages a in the abstracter, receiving only pure air to be heated, will not be
likely to become coated or obstructed with any deposit as will the passages b for
the escaping gasos. Both sets of passages can be cleared readily by removal of the
plato m at the rear of the abstracter, and by removal of the filling pieces a¹, b³,
seen in detail, Figure 10.
In some cases, as in boilers for naval and marine use, and whore on land large
power is located in confined space, and where usually small auxiliary or donkey
engines and boilers are kept in constant readiness for use, it may sometimes be
advisable to make use in connection with an exhauster of the waste gases of a
blower of any suitable form for forcing the pure air through the passages a in
re-inforcement of the exhauster, instead of simply allowing the air to follow naturally
the gases as removed by the exhauster.
In the Drawing n represents the device for forcing air into the passages a, it
being driven in any suitable manner. When the exhausting and forcing devices
are employed in combination, and when it is desirable to disuse the forcing device,
a valve or door o is made removeable to admit the air directly into the passages a.
In most cases the use of the exhaustor alone is preferable, as then the gases and
dust are not forced out of the furnace through crevices or through the firing and
ash-pit doors when these are opened for the duties of the firoman; and when the
pressure device in combination is used for supplying air it is preferable to regulate
its action so as to cause the pressure in the furnace not to exceed that of the atino-
sphere except in cases of emergency.
In the use of the abstracter the supply of a small surplus of air to the furnace
does not result in a material loss, inasmuch as the heat which it takes up in the
furnace and carries away from it is given back to the air passing to the furnace
through the medium of the abstracter.
In locomotives the exhauster and abstracter may be used in connection with the
furnace, which preferably should have its combustion chamber made as large as is
practicable. In such cases the exhaust steam should be let freely off from the
cylinder to relieve the pistons from back pressure.
The valves, i, are opened and closed through the valve rods ², and the
valves, k, through the rods, k³, see Figures 3 and 7. The heads of the rods j², ²,
•

page_text: are notched or otherwise suitably shaped to be locked in position, as are also the
sicms of the rods l² and k².
The Drawing, Figure 11, showing one embodiment of this Invention, represents
in central vertical sectional elevation a vertical tubular boiler for generating steam,
wherein provision is made for heating the incoming products of combustion to a
very high degree. In such Drawing air, either in its natural condition, or heated
in its passage through the abstracter before described, flows through the conveyer a³,
either above the fuel on the grates 6%, or both above and below, as may be deter-
mined by the position of the valves and d³, which are subject to the control of
the engineman or of the stoker, but when conveyed above the grates it passes into
a heating chamber or chambers instead of into the combustion chamber over the
fuel, as is the common practice.
The heating chambers are located within the space which would be, if not so
occupied, combustion chamber, and as they are subjected to a very high temperature
will preferably be made of refractory material, such as fire-clay. Of course such
heating chambers will vary in form and dimensions with the various forms and
sizes of the furnaces with which they are combined.
In the example illustrated the lower chamber e rests on a fire-brick ring f³,
resting on the grates, and supports an upper chamber g³.
The air entering from the conveyer as flows past the valve into heating
chamber e³, which is highly heated by the combustion of the fuel on the grates b³,
and after passing about the fire chamber, or nearly so, enters the chamber g³ through
suitable openings, and passes back through said chamber g³, from which it flows at
a temperature nearly coincident with the temperature of the combustion chamber
in fine streams through the perforations marked h³, and mingling with the gases
escaping from the incandescent fuel combustion of an intense and rapid character
is the result, consequent upon the affinity between highly heated oxygen and
carbon in a gaseous or finely comminuted form.
In the circular form of furnace shown the fire-clay tile chambers g³ and e³¸ are
made as segments with socket joints, which may be made tight by luting with
clay.
The passage e terminates at its end at or near the sides of the door space, but
the passage, which receives the heated air from passage c³, extends entirely about
the combustion chamber, but at or near the door space such passage is divided by a
vertical partition.
Engineers will at once recognize that the substantial equivalents of the devices
shown in Figure 11 may be applied, varied only in form, to any type of boiler,
such, as for example, a marine and locomotive, or to any kind of furnace for con-
suming fuel.
Having now described and particularly set forth the nature of the said Invention,
and the manner of carrying the same into effect, I would have it understood that
what I claim is,―
First. The combination of a furnace and abstracter with a mechanical exhauster,
substantially such as described to operate as and for the purpose set forth.
Second. The combination of an air-forcing device, furnace, abstracter, and a
mechanical exhauster, substantially such as described for the purpose specified.
Third. An abstracter composed of plates or sheets of conducting material formed
as described into chambers a, b, alternately arranged for passage of air and volatile
products of combustion, and removeable filling pieces, the abstracter being com-
bined with the discharging end of a furnace, and with the furnace space over the
grate bars.
Fourth. An exhauster and an abstracter with passages a, b, formed and arranged
as described in combination with the discharging end of a furnace, and by means
of a suitable passage with the space under the grate bars for the purpose described.
Fifth. An exhauster and an abstracter with passages a, b, formed and arranged
as described in combination with the discharging end of a furnace, and by means

page_text: of a suitable passage with the combustion chamber at or beyond the first bridge
wall, for the purpose described.
Sixth. An abstracter composed of metal plates or sheets placed with relation each
to the other, as shown, to form chambers a, b, and of removeable filling pieces to
permit the abstracter to be cleaned, substantially as described.
Seventh. A heating chamber or chambers substantially such as described located
within the combustion chamber and above the grate bars of a furnace, and arranged
to receive air to heat the same, and to deliver it highly heated in fine streams to
mingle with and perfect the combustion of the gases escaping from the fuel, sub-
stantially as described.
Eighth. The combination with a furnace provided with chambers e³ or g³, or
both, located within the combustion chamber of an abstracter and exhauster to
operate substantially as described.
In witness whereof, I, the said William Morgan-Brown, have hereunto set my
hand and seal, this Eighteenth day of December, in the year of our Lord
One thousand eight hundred and seventy-eight.
WILLIAM MORGAN-BROWN.
(LS.)