IMPROVEMENTS IN FURNACES AND APPARATUS FOR THE MANUFACTURE, AND FOR THE CONSUMPTION OR PREVENTION OF SMOKE
Year: 1859

page_text: LETTERS PATENT to William Richmond Alexander, of Glasgow, in the
County of Lanark, North Britain, Merchant, for the Invention of
"IMPROVEMENTS IN FURNACES AND APPARATUS FOR THE MANUFACTURE OF
Sealed the 29th April 1859, and dated the 26th January 1859.
PROVISIONAL SPECIFICATION left by the said William Richmond
Alexander at the Office of the Commissioners of Patents, with his
Petition, on the 26th January 1859.
1, WILLIAM RICHMOND ALEXANDER, of Glasgow, in the County of Lanark,
North Britain, Merchant, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN FURNACES AND APPARATUS FOR THE MANUFACTURE OF SUGAR,
AND FOR THE CONSUMPTION OR PREVENTION OF SMOKE," to be as follows, that is
to say:-
This Invention relates to the arrangement and construction of furnaces
and apparatus specially applicable to the manufacture of sugar, and also
suitable, to a greater or less extent, for consuming or preventing smoke in
furnaces generally. As adapted for the purposes of the sugar manufacture,
the arrangement consists of a long "fire mouth" or drying chamber, fitted up
iminediately in front of the furnace, such fire mouth or drying chamber being
formed with a double-bottom, perforated on the upper side for the discharge
into the chamber of the heated air. The "megass" or waste sugar cane is
deposited in this chamber, and pushed into the furuace frointime to time for
[Price 8d.]

page_text: use through a perforated door, which forms the communication between the
drying chamber and the furnace. The furnace bars are tubular, opening at
one end into a hollow fire-bridge at the back end of the furnace, and at the
other into the false bottom space of the front drying chamber. The grate
bars are also minutely perforated on their upper side for the discharge of air
amongst the burning fuel upon the bars. Air is forced into the furnace by a
blowing fan or other mechanical forcer at the extreme back end of the
structure of the furnace. The pipe from the fan conducts the air into and
through a set of heating cylinders or chambers studded with lateral spikes or
projecting pieces of metal inside and out, to enable the air to take up a
superior amount of heat; after leaving this heater, the air is forced along a
conducting pipe laid along the bottom of the main flue, and beneath the steam
boiler, usually fitted up at the after end of the structures, and beneath the
"teaches
or evaporating pans at the front. The air thus takes up heat as it
passes along until it is finally discharged into the hollow furnace bridge, whence
it passes partly into the furnace directly amongst the burning fuel, and partly
through the bars into the space of the false bottom of the drying chamber;
the latter portion dries the deposited megass, and then finds its way from the
chamber through the perforated division door into the furnace also; in this
way the full and efficient supply of highly heated air, subdivided into numerous
minute jets, effects the perfect combustion of the fuel, and prevents all or
nearly all discharge of smoke. The same arrangement or modifications of it
will answer for burning coal and other fuel.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Richmond Alexander in the Great Seal Patent
Office on the 13th July 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
RICHMOND ALEXANDER, of Glasgow, in the County of Lanark, North Britain,
Merchant, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of January, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said William Richmond Alexander, Her special license that I, the said
William Richmond Alexander, my executors, administrators, and assigns, or
.such others as I, the said William Richmond Alexander,my executors, adminis-

page_text: trators, or assigns, should at any time agree with, and no others, from
time to time and all times thereafter during the term therein expressed,
should and lawfully might make, 'use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel' Islands, and Isle of
Man, an Invention for "IMPROVEMENTS IN FURNACES AND APPARATUS FOR THE
MANUFACTURE OF SUGAR, AND FOR THE CONSUMPTION OR PREVENTION OF SMOKE," upon
thecondition (amongst others) that I,the said William Richmond Alexander,
byaninstrumentinwritingundermyhand and seal,should particularlydescribe
and ascertain the nature of the said Invention, and in' what mauner 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 Riclimond Alexander, do
hereby declare the nature of my said Invention, and in what manner the
Same is to be performed, to be particularly described and ascertained in and
bythe followingstatement, reference being had to the accompanying Drawings,
and to the letters and figures marked thereon, that is to say :-
Mysaid Invention relates to the arrangement and construction of furnaces
and apparatus specially applicable to the manufacture of sugar, and also
suitable, to a greater or less extent, for consuming or preventing sinoke in
furnaces generally. As adapted for the purposes of the sugar manufacture,
the arrangement consists of a long "fire mouth" or drying'chamber,fitted up'
immediately in front of the furnace, such fire mouth or drying chamber being
formed with a double bottom, perforated on the upper side for the discharge
into the chamber of heated air. The "megass" or waste sugar cane is
deposited in this chamber, and pushed into the furnace from time to time for
use through a perforated door, which forms the communication between the
drying chamber and the furnace. The furnace bars are tubular, opening at
one end into a hollow fire-bridge at the back end of the furnace, and at the
other into the false bottom space of the front drying chamber. The grate
bars are also minutely perforated on their upper side, for the discharge of air
amongst the burning fuel upon the bars. Air is forced into the furnace by a'
blowing fan or other mechanical forcer at the extreme back end of the
structure of the furnace. The pipe from the fan conducts the air into and
througha setof heating cylinders or chambers studded with lateral spikes or
projecting pieces of metal inside and out, to enable the air to take up a
superior amount of heat. After leaving this heater, the air is forced along a
conducting pipe laid along the bottom of the main flue,and beneath the steam
boiler, usually fitted up at the after end of these structures, and beneath the"
"

page_text: "teaches" or evaporating pans at the front. The air thus takes up heat as it
passes along until it is finally discharged into the hollow furnace bridge,
whence it passes partlyinto the furnace directlyamongst theburning fueljand
partly through the bars, into the space of the false bottom of the drying
chamber; the latter portion dries the deposited megass, and then finds itsway
from the chamber through the perforated division door into the furnace also;
in this way the full and efficient supply of highly heated air, subdivided into
numerous minute jets,effects the perfect combustion of the fuel, and prevents
all or nearly all discharge of smoke. The same arrangement or modifications
of it will answer for burning coal and other fuel.
And in order that my said Invention may be properly understood, I shall
now proceed to describe the several illustrative Figures on the explanatory
Sheets of Drawings, which I have hereunto appended for the purpose of
showingcertainmodificationsunderwhichmyimprovementsmaybejudiciously
carried out in practice.
"
In Sheet 1 of the accompanying Drawings, Figure 1 is a longitudinal
sectional elevation of one modification or arrangement of my improvements in
furnaces.and apparatus for the manufacture of sugar and the consumption or
prevention of smoke; Figure 2 is a plan of the arrangement corresponding to
Figure 1; and Figure 3 is a transverse section of the drying chambers
in which the matters used as fuel are primarily placed. According to the
arrangement shown in Sheet 1 of the accompanying Drawings, the apparatus
is built in a structure of brickwork A, in which is constructed a flue B, that
extends from end to end of the apparatus. Above the flue a series of
evaporating pans or "teaches are placed, which in the accompanying
Drawing are numbered 1 to 5.
At the front end of the apparatus the
flue B opens into a furnace C, the fire bars D of which are made hollow
throughout, the upper surface being finelyperforated. The ash-pit E belowthe
bars D is closely shut by means of a door to prevent the admission of air
thereto; the chimney F in this Drawing is of the usual construction. The
supply of air for the combustion of the fuel in the furnace is forced bymeans
of a blowing fan or air-pump or other mechanical means through the pipe G,
into a compartment of the cylindrical heating chamber H, placed in the flue
leading to the chimney. In this Drawing the heating chamber is shown as
consisting of two cylinders arranged concentrically, the inner one being open
from end to end, and the space I between the inner and outer cylinders, which
serves as an air-heating chamber, being enclosed at each end with metal
plates. The surfaces of the cylinders are studded with spikes or flanges or
bosses of metal, which project in a radial direction from both sides of the

page_text: cylinders, these spikes beingthus arranged for the purpose of rapidly absorbing
heat from the gaseous products of combustion as it passes to the chimney,
and .of.imparting..the heat .to.. the. air as it is forced.through the air-
heating chamber. The air, after passing through the heating chamber I,
descends by the pipe J, which branches off laterally, is carried along the whole
length of the apparatus,and is discharged at the front extremity of the pipe J
into the hollow fire-bridge K, which forms the back part of the furnace C.
The fire-bridge K forms a chamber which extends across the furnace, the
front part being perforated to allow of the emission directly into the,furnace of
a portion of the stream of heated air that is forced through the pipe J. The
pipe J and the fire-bridge K are made of cast iron, but may be made of fire
clay or cast iron or other material, covered or protected from the action of the
fire by a covering of fire clay or other fire-resisting material. The other
portions of the heated air passes into the hollow fire-bars D, the backward
ends of which enter the lower part of the hollow fire-bridge K. The per-
forations made through the upper part of the fire-bars D permit a portion of
the heated air to pass through amongst the fuel lying on the, fire-bars, the
quantity thus conveyed to the fuel being sufficient to keep it in a state of
active combustion.
•
:
In the manufacture of sugar the waste cane after the juice has been
expressed therefrom, and which is termed "megass," is used as fuel, and in
the accompanying Drawing a chamber for drying the megass is shown as
arranged for use in conjunction with my improvements; this portion of the
apparatus consists of a drying chamber L, made of cast iron or other material;
the chamber is of a rectangular figure, and is divided into three oblong
chambers by the vertical partitions M, as shown in the plan, Figure 2, and the
transverse section of the chamber, Figure 3. The front ends of these several
chambers are closed by means of the doors N, which afford access to the
interior of each chamber for the purpose of filling it with megass, or discharging.
the same into the furnace. The bottom of the drying chamber L inclines
downwards to the level of the fire-bars D, the front ends of which enter the
lower part of the chamber L, so that that portion of the heated air which
does not pass into the furnace is carried into the chamber L, and serves to
dry the megass. The fuel to be dried rests upon the perforated diaphragm or
false bottom 0, which is arranged on a level a little above the furnace bars D.
In this manner the space below the false bottom O serves as a chamber for the
heated air, which rises and passes through the megass that is placed in the
compartments above it. The quantity of air thus admitted to the drying.
chamber Lis regulated a valvular door, which is moved by the hand..

page_text: of
any
lever D. The roof of the chamber L is furnished' with a short tubular
aperture P, which admits of steam that is driven' off from the damp megass
escaping into the air, or it may be carried into the chimney; this steam or
vapour is prevented from entering the furnace C by means of a damper Q
fitted in each compartment of the drying chamber L. The dampers Q are
severally connected by means of a shackle and chain to a counterweight Q¹; the
chains pass over pulleys, the spindles of which are carried in the framing R..
At the backward end of each of the compartments of the drying chamber Lis
fitted a hanging door S, swinging loosely; these doors are perforated to allow
combustible gaseous matters escaping into the furnace C, where they
become ignited. The dampers Q are only kept down during the preliminary
drying of the damp megass, and as the furnace C requires' replenishing
the charges of dried and highly heated fuel are successively pushed out of each
compartment into the furnace. Thus as the fuel in the compartments becomes
heated, the inflammable gases escape in minute gets through the perforations
in the hanging doors, and, mixed with air, these matters are deflected down-
wards amongst the highly incandescent fuel in the furnace, when they meet
a further supply of heated air discharged in jets from the front of the fire
bridge K, fit for immediate and rapid combustion; every particle of inflam-
mable matter is thus instantly flashed into flame, so that no visible smoke
escapes from the chimney F, whilst the fuel is economised in the highest
degree. The flame arising from the burning fuel'in the furnace C passes
along the flue B; and is carried to the backward extremity of the apparatus,
where the flue diverges laterally, and enters the shaft or chimney F. On
its passage through the flue the tame heats the several sugar pans l' to 5,
and also the multitubular boiler V, the steam of which serves to drive the
engine. To raise steam in the boiler V, at the commencement of operations
fire is lighted in the furnace U, but when the apparatus is in full operation,
the heat that flows through the flue B is sufficient to generate steam in tlie
boiler V. A door W is fitted in the brickwork to afford access to the boiler
for cleaning the tubes or other purposes, and the damper T serves to control
the velocity of the current of flame through the 'flue. These several parts
being, however, in all respects similar to those in ordinary use, it is unneces-
sary to enter into a more particular description.
In Sheet 2 of the accompanying Drawings my improvements are shown as
applied to an ordinary furnace of a steam boiler. Figure 1 on the said Sheet
is a longitudinal vertical section of the arrangement; 'and Figure 2 is an end
elevation, partially in section In this modification the brickwork A'in which
the boiler B is set; is modified to a 'very trifling extent from the ordinary

page_text: arrangement. The furnace doors C, instead of opening at once into the
furnace in the usual way, serve to enclose the elongated furnace mouth or
coking chamber D. This chamber is made with a perforated false bottom or
diaphragm E, on which the fuel rests, the space below the false bottom
serving to receive the heated air, in manner similar to the arrangement shown
on Sheet 1 of the accompanying Drawings. At the backward end of the
chamber D a perforated door F is suspended, swinging freely on its hinges,
for the purpose of deflecting downwards and thoroughly mixing the air and
gases as they pass into the furnace G, by means of the numerous orifices in
the hanging door, as already described. The furnace G is fitted with hollow
bars H, which serve to convey the current of heated air to the space below the
chamber D. A portion of the heated air is, however, allowed to escape
through the perforations made in the upper sides of the bars, this portion of
the heated air serving to support the combustion of the fuellying on the bars.
The stream of heated air is conveyed to the furnace and coking chamber by
the pipe I, which is carried along the lower part of the flue J. The front
extremity of the pipe I enters the hollow bridge K, which extends across the
furnace from side to side, and which may be made of metal or fire clay, as
already described. The front side of the fire bridge K is perforated, to allow
of the escape of a portion of the heated air directly into the furnace through
numerous orifices, so as to meet and combine with the gases evolved from
the fuel in the body of the furnace G and the coking chambers D. The
backward extremity of the pipe I enters the heating chamber L, which in
this modification is arranged in a vertical position in the chimney M; the
heating chamber consists of concentric cylinders having radially projecting
spikes of metal N, arranged in manner similar to the modification shown in
Figures 1 and 2 in Sheet 1 of my Drawings. The air for the supply of the
furnace is forced by a fan blast or other mechanical means into the pipe O, and
passes downwards between the outer and inner cylinders of the heating
apparatus, so that, as already described, the caloric from the escaping current
of the products of combustion is caught up by means of the radially projecting
spikes or flanges, and communicated to the ingoing current of pure air that is
being forced downwards. The back part of the flue J is furnished with a
damper P, by means of which the size of the aperture of the flue may be
increased or diminished as required. The ash-pit Q is closed by a tightly
fitting door, to prevent the admission of air in that direction. The quantity
of air admitted to the coking chamber D may be regulated by the valvular
apparatus R with the handle S.
In Sheet 3 of the accompanying Drawings is shown one mode of adapting

page_text: my improvements to the boilers of marine engines. Figure 1 on the said
Sheet is a front elevation of the boilers of a marine engine; the Figure is
drawn partially in section, to show the internal arrangement; the ac-
companying view, Figure 2, is a longitudinal vertical section corresponding
to Figure 1. In this modification of my improvements the boiler B is con-
structed in the usual manner. The furnace doors C open into the coking
.chambers D; the bottom of each chamber is perforated for the admission of
heated air from the chamber E. The gaseous matters as they are evolved
from the heated fuel escape through the perforations in the hanging door F
into the furnace G, where they are ignited as they pass over the incandescent
fuel. The steam of heated air passes into the chamber E along the hollow
bars H; a portion of the air escapes through the perforations in the bars,
which portion serves to maintain the combustion of the fuel in the furnace.
The full supply of air for the furnaces is conducted by means of the pipes I,
through the boiler and flue J, into the hollow fire bridge K, from whence a
portion of the air passes through the perforations in front directly into the
furnace, and the remaining portion goes through the hollow bars H. The
upward extremity of the pipe I enters the heating-chamber L, which in this
modification consists of duplex concentric cylinders, arranged so that the
-upward current of the products of combustion flows in two columns, passing
through the open-ends of the inner cylinder and between the inner and outer
-cylinders. The ingoing current of pure air is forced by the fan blast or air
-pump through the supply pipe-O, the inner part of which branches out
laterally into two pipes, which enter the outer cylindrical heating chamber at
opposite sides of the funnel M, as shown in Figure 1 on Sheet 3 of the
accompanying Drawings. The air as it is forced into the heating chamber
-passes, upwards between the walls of the outer cylinders and flows through
-the lateral openings at the upper part into the inner cylinder; it then passes
downwards to the pipe I, and is conducted to the furnaces. The ingoing
current of air in its passage through the heating chambers thus takes up, as
already described, in reference to the other modifications, that amount of
-caloric which is ordinarily allowed to escape into the atmosphere through the
funnel for the purpose of producing a draught. The admission of air through
the ash-pit N is prevented by means of the close door P, and, it necessary,
the quantity of air admitted to the coking-chamber D may be regulated by
the valve Q moved by the hand lever R.
In the foregoing description of my Invention I have spoken only of con-
veying a current of air through the entrance pipes G and O of the several
Drawings; but I propose when the nature of the fuel shall render it expedient

page_text: to convey a jet of steam into the air pipe, and so cause the mingled air and
steam to enter the furnace. By this arrangement I provide that the pipes
are preserved to a great extent from being burnt, and as the steam escapes
through the various orifices into the furnace and amongst the incandescent
fuel on the bars at a very high temperature, it will become decomposed into
its gaseous elements, and thus assist in maintaining the vivid combustion of
the fuel.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, I may observe, in conclusion,that I do not confine or restrict myself
to the precise details or arrangements which I have had occasion to describe
or refer to, as many variations may be made therefrom without deviating
from the principles or main features of my Invention; but what I consider to
be novel and original, and therefore claim as the Invention secured to me by
the herein-before in part recited Letters Patent, is,-
First, the general arrangement and construction of furnaces and the
apparatus connected therewith, for the more effective combustion of the fuel
and the gaseous products arising therefrom, as herein-before described.
Second, the arrangement and construction of the drying or coking chambers
for effectually drying or coking fuel preparatory to introducing it in a highly
heated state into the furnace, as herein-before described.
Third, the application and use of a damper or valvular apparatus in each
drying chamber, for the purpose of preventing the admission of steam or
aqueous vapour into the furnace from the fresh charges of "megass," as
herein-before described.
Fourth, the application and use of the perforated hanging door, fitted to
the back extremity of each drying or coking chamber, for the purpose of
distributing and mixing the air with the gaseous products arising from the
fuel as it becomes heated in the drying or coking chambers, as herein-before
described.
"1
Fifth, the system or mode of applying and conveying a current of heated
air to the drying or coking chambers, for the purpose of drying the fuelwhere
megass" or spent or crushed sugar cane is used, and for the purpose of
heating and driving off its gaseous elements, and for the purpose of drying or
heating coal or other fuel, and driving off the gaseous matters arising there-
from, and conveying them into the furnace, as herein-before described and
shown in the accompanying Drawings, or any mere modification of the said
arrangement.
Sixth, the arrangement and construction of the hollow furnace bars per-

page_text: forated through their upper surfaces, for the purpose of conveying a current of
heated air, or a mingled current of heated air and steam to the fuel in the
furnace, so as to promote its active combustion, as herein-before, described.
Seventh, the application and use of the hollowfire bridge perforated through
its side next the fire, for the purpose of dividing the current of heated air or
of air and steam into numerous streams at the part of the apparatus where
these streams are brought into contact with the gaseous products of com-
bustion in the furnace, as herein-before described.
Eighth, the system or mode of combining or mingling and using, when
expedient, a current of air and steam, the latter being introduced for the
purpose of preserving the pipes, and by its decomposition promoting the com-
bustion of the fuel and gases in the furnace, as herein-before described.
Ninth, the arrangement and construction of the heating chamber or
apparatus through which the air or air and steam first passes; also the
system or mode of abstracting the last portion of heat from the uninflammable
gaseous products of combustion before they are allowed to escape through the
chimney, so as to utilize as far as possible the heat evolved from the fuel
consumed in the furnace, as herein-before described and shown in the
accompanying Drawings.
In witness whereof, I, the said William Richmond Alexander, have
hereunto set my hand and seal, this Twelfth day of July, One
thousand eight hundred and fifty-nine.
W. R. ALEXANDER. (L.S.)