IMPROVEMENTS IN BOILER FURNACES
Year: 1882

page_text: LETTERS PATENT to John Rankine Russell of Glasgow in the County of
Lanark, North Britain Engineer for an Invention of "IMPROVEMENTS IN
BOILER FURNACES."
PROVISIONAL SPECIFICATION left by the said John Rankine Russell at
the Office of the Commissioners of Patents on the 12th September 1882.
JOHN RANKINE RUSSELL, of Glasgow, in the County of Lanark, North Britain,
Engineer, "IMPROVEMENTS IN BOILER FURNACES,"
This Invention relates to improvements in steam boiler furnaces designed for
burning such fuel as husks of rice or paddy, sugar cane megass, wooden chips and
sawdust, or coal dross or dust.
The improved furnace which is particularly adapted for use in connection with
land boilers, is fitted or erected entirely outside the boiler, but connected with the
flue or flues or fire box of the boiler with which it is combined, which may be of
the ordinary Cornish, Lancashire, or Locomotive type, or of any special type.
According to one modification, the improved furnace comprises a large and
nearly rectangular chamber of brick work with an arched or flat roof through which
the loose rice husks or other similar fuel, is fed by one, two, or more hoppers.
The fire-grate is of semi-circular or highly curved and closely packed fire bars
arranged to form either a single longitudinal arch, or as is preferred, two or more
arches disposed in longitudinal and parallel lines, and extending from the front of
the furnace to a bridge near the back end. The ash-box is formed below the fire-
grate with sides sloping inwards to the front, where a deep recess is formed to
receive the ashes, and from which the ash may be removed by a stream of water or
by raking periodically. Between the fire-grate and the sloping sides of the ash-
box, binged or jointed doors are fitted, which may be opened or closed from the
outside by levers to clear the sides of the grate of burnt fuel. Combustion of the
fuel over the grate is forced and maintained by a blast of air admitted through a
perforated pipe fitted below the arch of each grate and projecting beyond the front
of the furnace, where the pipes are connected to a blowing fan or blower. Air
...

page_text: may however be blown direct into the ash pit. The flame and products of com-
bustion pass over the bridge into a combustion chamber, in which is by preference
formed a hanging bridge in order to prevent the direct outflow of the fire gases,
and cause the sparks or solid particles of the burning fuel to be deposited in the
bottom of this chamber, whence they may be removed periodically.
From the combustion chamber, the fire gases pass direct through openings or
passages into the flues or fire-box of the steam boiler, which is combined with the
furnace, and is fitted immediately behind it.
When there are two or more flues in the boiler, the openings or passages from
the combustion chamber are made to correspond, and a corresponding number of
fire grates may also be fitted within the furnace.
The hoppers through which the loose fuel is admitted to the furnace, are by
preference made to terminate in long narrow openings directly over the centre of
each longitudinal fire-grate, and the admission of the fuel is controlled and
regulated by means of valves, or by rollers fitted in such openings, or in the necks
of the hoppers and operated by hand levers or gearing outside. The perforated
pipes through which the air is forced to maintain combustion, are by preference
carried through the bridge behind the fire grate, and have an outlet into the
combustion chamber behind, a valve or similar device operated by a hand lever
from the front being provided to regulate the admission of the air to the com-
bustion chamber. A water pipe or tube also provided with a controlling valve, is
fitted in the lower part of the ash box by means of which the falling ash may be
floated away or periodically cleared out, while the water forms a seal or trap to
prevent the escape of the air which is forced in to maintain combustion.
When the furnace is intended to burn certain kinds of fuel, tubes or pipes are
led into the sides of the combustion chamber, through which petroleum or other
similar liquid hydro-carbon is forced by jets of steam in the form of spray, which
in contact with the hot fire gases ignites and produces an intensely hot flame.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Rankine Russell in the Great Seal Patent Office on the
10th March 1883.
JOHN RANKINE RUSSELL, of Glasgow, in the County of Lanark, North Britain,
Engineer. "IMPROVEMENTS IN BOILER FURNACES."
My said Invention relates to improvements in steam boiler furnaces designed
for burning such fuel as husks of rice, or paddy, sugar cane megass, wooden chips
and saw-dust or coal dross or dust.
The improved furnace, which is particularly adapted for use in connection with
land boilers, is fitted or erected entirely outside the boiler, but connected with the
flue or flues or fire-box of the boiler with which it is combined, which may be of
the ordinary Cornish, Lancashire, or Locomotive type, or of any special type.
My Invention is illustrated by the accompanying Drawings in which figure 1
is a longitudinal vertical section of a modification of my improved boiler furnace as
applied outside the boiler flue; And figure 2 is an end view of the same, partly in
elevation and partly in section. Figures 3 and 4 are corresponding views of
another modification of my improved boiler furnace partly fitted within the boiler
flue.
In the modification represented in figures 1 and 2, the improved furnace
comprises a large and nearly rectangular chamber A of brickwork, with an arched
or flat roof A¹ through which the loose rice husks, or other similar fuel, is fed by
one, two, or more hoppers B, B. The fire-grate C is of a semi-circular form of
highly curved and closely packed fire-bars c arranged to form either a single
longitudinal arch, or as is preferred, two or more arches C, C, disposed in
longitudinal and parallel lines, and extending from the front of the furnace
chamber A to a bridge D near the back end. The curved fire-bars c of which only
a few are shown, are supported at their ends by longitudinal bearing bars c¹, and.
at the centre by projections formed on the air admission pipes E hereinafter referred
to. The ash box F is formed below the fire-grate C with sides sloping inwards and
towards the front, where a deep recess F' is formed to receive the ashes, and from
which the ash may be removed by a stream of water, by a rotating screw, or by
raking periodically.
Between the fire-grate C and the sloping sides of the ash-box F, hinged or
jointed doors c² are fitted, which may be opened or closed from the outside of the
furnace by levers c³ to clear the sides of the grate C of burnt fuel. Combustion of
the fuel which lies in a thick layer over the grate C is forced and maintained by a
blast of air admitted through a perforated pipe E fitted below each arch of the
fire-grate C and projecting out through and beyond the front of the furnace, where
the pipes E are formed with branches E¹ by which they are connected to a blowing
fan or blower. Air may however be blown direct into the ash pit to pass through
the fire-grate C. The flame and hot products of combustion pass over the bridge D
into a combustion chamber G, in which is by preference formed a hanging bridge D¹
in order to prevent the direct outflow of the fire gases, and cause the sparks or
solid particles of the burning fuel to be deposited in the bottom G¹ of this chamber
whence they may be removed periodically through doorways which may be provided
for the purpose.
From the combustion chamber G which is built of brickwork, the fire gases
pass direct through openings or passages G into the flues or fire-box H of the
steam boiler I, which is combined with the furnace A, and is fitted immediately
bebind it.

page_text: When there are two or more flues in the boiler, the openings or passages G³ from the
combustion chamber G, are made to correspond, and a corresponding number of fire-
grates C may also be fitted within the furnace chamber A. The hoppers B, B through
which the loose fuel is admitted to the furnace chamber A, are by preference made to
terminate in long narrow openings B₁ directly over the centre of each longitudinal
arch of the fire-grate C, and the admission of the fuel is controlled and regulated by
means of valves, or by rollers b fitted in such openings B', or in the necks of the
hoppers B and operated by hand levers 62, 63, or by gearing outside. The perforated
pipes E through which the air is forced to maintain combustion, are by preference
carried through the bridge D behind the fire-grate C, and have an outlet into the
combustion chamber G behind. A valve or grating E2 or similar device connected
to a long bar e, and operated by a hand lever e' from the front is provided to
regulate the admission of the air to the combustion chamber G. A water pipe or
tube J also provided with a controlling valve J is fitted in a recess formed in the
sides or in the lower part of the ash box F, and out of this pipe J water is allowed
to flow into the ash-box F. By this means the falling ash may be floated away or
periodically cleared out of the bottom of the ash-box by an opening J2 in the front
wall of the furnace. The recess F into which the ashes are deposited and from
which they are ejected by the flowing water is covered by a door or doors J³, which
may be opened periodically for the passage of the ashes.
When the furnace is intended to burn certain kinds of fuel, injection tubes or
pipes are led into the sides of the combustion chamber G through which
petroleum or other similar liquid hydrocarbon is forced by jets of steam in the
form of spray, which in contact with the hot fire gases within the chamber G
ignites and produces an intensely hot flame flowing directly into the boiler-flue or
fire-box H.
In the modification of the improved furnace shown in figures 3 and 4, the loose
fuel is fed through a hopper B fitted in front of the boiler I into a chamber A
formed in front of the boiler flue or fire-box H. The fuel falls on to a grating C
formed by an endless band of fire-bars which is traversed slowly over large end
rollers C¹, and over supporting rollers C² carried in bearings in frames C³ fitted
inside the flue H. A bridge D is formed at the end of the fire-grate C, and between
this bridge and the inner end of the fire-grate C, the burnt fuel falls, and is
withdrawn towards the front of the furnace by a long rotating screw K. The
traversing motion of the endless band forming the fire-grate is obtained from a
rotating worm L gearing into a worm wheel L¹ on the spindle of the front
roller C over which the band passes. Air is admitted for the combustion of the
fuel, through openings or regulating gratings M in the front of the chamber A, and
through openings m in front of the traversing band C. Air may be forced into the
space enclosed by the band C and caused to pass up through between the bars of
the band or fire-grate C to promote combustion of the fuel. The flame and hot
products of combustion passing over the bridge D into the flue H of the boiler I
return by return flues H¹ enclosed between the boiler shell and the supporting
brickwork I. In these flues H¹ recesses h are formed into which the sparks and
burnt particles which may collect in the flues H₁ are allowed to drop by opening
hinged or jointed valves or doors c² fitted over these recesses and provided with
hand levers outside. From these recesses the consumed material may be removed
periodically.
Having thus described the nature of my said Invention, and the manner of
performing the same, I have to state that I do not confine myself to the precise
details herein described or delineated, but what I consider novel and original, and
therefore claim as the Invention secured to me by the hereinbefore in part recited
Letters Patent is,―
First. The arrangement and combination of parts of boiler furnaces for burning
rice husks or paddy, sugar cane megass, saw-dust, dross, or similar fuel, substantially
as herein described and illustrated by the accompanying Drawings.
Second. A boiler furnace for burning rice husks, saw-dust, dross, or similar loose

page_text: or pulverulent fuel, consisting of a furnace chamber fitted with a single or multiple
arched fire-grate over a close ash-box, and a combustion chamber from which the
flames or fire-gases pass to the heating flues or fire-box of the boiler, substantially
as herein described and illustrated by the accompanying Drawings.
Third. In a boiler furnace for burning rice husks, saw-dust, dross, or similar
loose or pulverulent fuel, the construction and combination of one, two, or more
series of curved fire-bars forming a single or multiple arched fire-grate on which the
fuel is burned, and through which the air to support combustion is forced,
substantially as herein described and illustrated by the accompanying Drawings.
Fourth. The combination in a boiler furnace for burning rice husks, saw-dust,
dross, or similar loose or pulverulent fuel, of a single or multiple arched fire-grate
carrying the burning fuel, a hopper or hoppers supplying the fuel thereto, and a
close ash-box into which the burnt fuel is allowed to fall by the doorways formed
between the fire-grate and such ash-box, substantially as herein described and
illustrated by the accompanying Drawings.
Fifth. In a boiler furnace for burning rice husks, saw-dust, dross, or similar loose
or pulverulent fuel, the construction and arrangement under the fire-grate or within a
close ash-box of the perforated air admission pipe provided with a regulating outlet
valve orifice or grating beyond the bridge and operated by a hand lever outside,
substantially as herein described and illustrated in the accompanying Drawings.
Sixth. In a boiler furnace for burning rice husks, saw-dust, dross, or similar loose.
or pulverulent fuel, the combination with the furnace chamber, of a combustion
chamber provided with tubes or jets for the injection into such chamber of liquid
hydrocarbons and steam substantially as herein set forth.
In Witness Whereof, I the said John Rankine Russell, have hereunto set my
hand and seal this Eighth day of March, in the year of our Lord One
thousand eight hundred and eighty-three.
30
Witness
WALLACE FAIRWEATHER C.E. Fel. Inst. P.A.
of the firm of
W. R. M. Thomson & Co
Patent Agents
Glasgow
J. R. RUSSELL, (L.S.)