Improvements in Rotating Furnaces for Roasting or Calcining Ores or other Substances.
Year: 1889

page_text: Date of Application, 5th Dec., 1889
Complete Specification Left, 3rd Sept., 1890-Accepted, 4th Oct., 1890
PROVISIONAL SPECIFICATION.
Improvements in Rotating Furnaces for Roasting or Calcining Ores
or other Substances.
I, STEPHEN ALLEY, of the Sentinel Works, Polmadie, in the County of Renfrew,
North Britain, Engineer, do hereby declare the nature of this invention to be as
follows, that is to say:
:-
My said invention has for its object the constructing of rotating furnaces in an
improved manner, and so that each furnace may be built up of a number of similar
parts of sizes convenient for stowage and conveyance, and any of which can be easily
replaced.
In carrying out my invention 1 construct the rotating part of the furnace of an
elongated cylindrical form by means of a number of iron segments of equal size and
formed with external segments by means of which they are bolted or riveted together.
It is convenient to have four segments circularly and as many longitudinally as will
make each about 30 inches long. Between the longitudinal joints narrow plates are
fixed and projecting inwards retain segmental firebrick lining pieces which are, by
preference, longitudinally corrugated on their inner surfaces. The furnace is encircled
by rings in suitable positions and by means of them rests on rollers some of which
are driven by gearing so as to make the furnace rotate. One end of the rotating
furnace communicates with a stationary fire place or fuel grate and the other end
with a stationary smoke box. A chimney extends up from the smoke box and is by
preference made with two shells between which the air for combustion is made to pass
so as to take up and utilise waste heat. The air may also be heated by passing
through stacks of tubes heated externally by the waste furnace gases.
The ores or materials to be operated on are introduced by means of a hopper beyond
the smoke box, from which hopper they are passed in across the smoke box by a
helical feeder working in a passage formed in a casting with a jacket space for water
to prevent premature heating of the materials. The rotating furnace is inclined
downwards from the smoke-bex end, and the ores or materials are by the rotation
made to move gradually towards the other end where they are delivered into a
chamber provided in the structure in which the fire place or fuel grate is formed
The air heated by the waste gases is led through pipes from the smoke box to
the fire place.
Dated this Fourth day of December 1889
EDMUND HUNT,
Applicant's Agent.
COMPLETE SPECIFICATION
Improvements in Rotating Furnaces for Roasting or Calcining Ores
or other Substances.
I, STEPHEN ALLEY, of the Sentinel Works, Polmadie, in the County of Renfrew,
North Britain, Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement, that is to say:
My said invention has for its object the constructing of rotating furnaces in an
improved manner, and so that each furnace may be built up of a number of
similar parts of sizes convenient for storage and conveyance, and any of which can
be easily replaced.
In carrying out my invention 1 construct the rotating part of the furnace of

page_text: an elongated cylindrical form by means of a number of iron segments of equal
size, and formed with external flanges, by means of which they are bolted or
riveted together. Between the longitudinal joints narrow plates are fixed, and
projecting inwards retain segmental firebrick lining pieces which are by preference
longitudinally corrugated on their inner surfaces. "One end of the rotating furnace
communicates with a stationary fire place in which solid or gaseous fuel may be
burned; and the other end communicates with a stationary sinoke box from which
a chimney extends upwards. The ores or materials to be operated on are intro-
duced by means of a hopper beyond the smoke box, from which hopper they are
passed in across the smoke box by a helical feeder working in a passage which
may be formed in a casting made with a jacket space for water to prevent pre-
mature heating of the materials. The rotating furnace is slightly inclined down-
wards from the smoke box end and the ores or materials are by the rotation made
to move gradually towards the other end where they are delivered into a chamber
provided in the structure in which the fire place is forined.
A roasting or calcining furnace as constructed according to my invention is
shown on three accompanying sheets of explanatory drawings-on which
Figure, 1, sheet, 1, is an outline small-scale side elevation, the remaining figures
being drawn to a larger scale.
Figure, 2, is a side elevation of the fire-place end;
Figure, 3, a transverse vertical section of the rotating part of the furnace ;
Figure, 4, a horizontal section of the fire-place end and part of the rotating piece,
Figure, 5, sheet. 2, a side elevation of the smoke-box end; and
Figure, 6, a sectional plan corresponding to Figure, 5.
Figures, 7, and 8, sheet, 3, are horizontal and vertical sections of the fire place as
modified for using gaseous fuel.
In these drawings the same reference numerals are used to mark the same or like
parts wherever they are repeated.
The rotating furnace is an elongated cylinder built up of segmental iron plates, 10,
formed with flanges by means of which they are bolted together. Long narrow
plates, 11, are inserted between the longitudinal joints of the segmental plates, 10,
and are placed radially and so as to project inwards. The radial plates, 11, hold
in position internal lining slabs, 12, of firebrick which are corrugated on their
surfaces so as to carry round the ores or materials passing through the furnace.
The cylindrical furnace, 10, is encircled at suitable points by stout iron rings, 13,
secured by means of flanges formed on them and inserted in circular joints of the
furnace segments, 10. By means of the rings, 13, the cylindrical furnace rests
and turns on rollers, 14, 15, some of which are driven, being on a shaft, 16, which
is driven from any suitable prime mover.
The fire place shown on sheet, 1, is provided with grate bars, 17, for solid fuel ;
it is built up of flanged iron plates, 18, of conveniently transportable sizes, and
is lined with firebricks or slabs. The fuel space is divided by a bridge or wall, 19,
indicated by dotted lines in Figure, 2, froni a space, 20, into which the ores or
materials which have passed through the furnace are received, and from which
they are withdrawn periodically through side doors, 21.
At the other end of the cylindrical furnace, 10, there is a smoke box, 22, built
up of iron plates of conveniently transportable sizes. It is provided with side
doors, 23, to give access to the interior, and is surmounted by a chimney, 24.
The ores or materials to be passed through the furnace are supplied into a
hopper, 25, at the smoke-box end; and from this hopper they are moved down
in a regulated manner by a rotating paddle, 26, into a horizontal feed pipe, 27.
Within this feed pipe, 27, which projects a short distance into the end of the
rotating cylindrical furnace, there is any suitable form of conveying screw or helix
(which, however, is not shown) which delivers the ore or materials into the furnace.
The conveying screw is worked by means of a pair of bevil wheels, 28, from a
shaft, 29, which receives motion by means of a belt, 30, and pulleys from a shaft, 31,

page_text: driven by a pair of bevil wheels, 32, from the shaft, 16, which turns the rotating
furnace, 10. The hopper paddle, 26, is driven by means of a belt, 33, and pulleys
from the shaft, 29.
In the arrangement for gaseous fuel shown in Figures 7 and 8, sheet, 3, the pro-
ducer gas or other combustible gas passes from a supply main, 34, by a branch flue, 35,
into the combustion chamber, 36; and the air for combustion which enters that
chamber by a port, 37, is heated by passing through a space or flue, 38, formed
between the outer shell of the fire place, 18, and an inner firebrick lining, 39, to which
space, 38, the air has access by an inlet hood, 40. If desired the air for combustion
may be heated by being made to pass through a jacket space constructed round the
chimney, 24, or through tubes heated by the used fire gases.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is :-
1. Constructing and combining the parts of rotating furnaces for roasting or
calcining ores or other substances, in the improved manner substantially as herein-
before described.
2. The improved construction of rotating furnace cylinder, the same being built up
of segmental plates with radial plates projecting inwards to hold firebrick lining slabs
substantially as hereinbefore described.
3. Forming the firebrick lining slabs of the rotating furnace cylinder with corru-
gated surfaces substantially as herein before described.
4. The combination with the rotating furnace cylinder, of a feeding pipe extending
thereinto across the smoke box, and having a conveying screw or helix working in it,
substantially as hereinbefore described.
Dated this Second day of September 1890.
EDMUND HUNI,
Applicant's Agent.