IMPROVEMENTS IN FURNACES FOR ROASTING ORES
Year: 1876

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"IMPROVEMENTS IN FURNACES FOR ROASTING ORES." A communication from
abroad by Henri Herrenschmidt, of Melbourne, Victoria, Australia, Civil
Engineer.
Sealed the 30th September 1876, and dated the 4th July 1876.
PROVISIONAL SPECIFICATION left, by the said William Robert Lake at the
Office of the Commissioners of Patents on the 4th July 1876.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN FURNACES FOR ROASTING
ORES." A communication.
This Invention consists, first, in making the roasting or purifying chamber of a
conical or taper form.
Secondly. In dividing the said chamber into longitudinal compartments throughout
a part or the whole of its length.
Thirdly. In making the fire-place and the receiver for the roasted ore movable.
And, Fourthly. In providing the said movable fire-place with a chamber above
for the generation of hydrogen gas when required.
The roasting chamber I set horizontally, the smaller end being the feed and the
larger the discharge end. The fire-place is at the latter end, and the chimney stack
at the former end.
In a forty feet chamber the larger end should be about three feet more in
diameter than the smaller end. It revolves on friction rollers supported on suitable
piers. The said chamber may be divided into two or more longitudinal compart-
ments, and the outer casing may be triangular, square, or polygonal. Passages
are provided for the admission of air to either the upper or lower half of the said
chamber. When the material requires to be treated with hydrogen gas the divisions
must extend the whole length of the chamber and terminate in separate ascending.
flues.

page_text: The fire-place is carried on wheels running on rails to admit of its easy removal
in the event of its becoming necessary to look into the body of the roasting chamber,
or to substitute one with a hydrogen gas generator for a fire-place without one, or
vice versa.
The roasted orc receptacle being made movable, as described, gives greater facility
for the removal of the ore treated.
The revolving motion is very slow, say, one revolution in five minutes, and it
may be either continuous or intermittent, the object being to subject the material
under treatment to the action of heat and atmospheric air, or heat and hydrogen
gas alternately.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Robert Lake in the Great Seal Patent Office on the 3rd
January 1877.
800
1:200
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN FURNACES FOR ROASTING
ORES." A communication from abroad by Henri Herrenschmidt, of Melbourne,
Victoria, Australia, Civil Engineer.
This Invention consists, first, in making the roasting or purifying chamber of a
conical or taper form.
Secondly. In dividing the said chamber into longitudinal compartments through-
out a part or the whole of its length.
Thirdly. In making the fire-place and the receiver for the roasted ore movable.
Fourthly. In providing the said movable fire-place with a chamber above it for
the generation of hydrogen gas when required.
The roasting chamber is set horizontally, the feed being at the smaller end and the
discharge at the larger end. The fire-place is at the latter end and the chimney
stack at the former end.
In a forty feet chamber the larger end should be about two feet more in diameter
than the smaller end. The said chamber revolves on friction rollers supported on
suitable piers. The material is fed through an inclined shoot, around the mouth of
which is a cast-iron plate working against a ring on the inner periphery of the
chamber to prevent the material falling backwards instead of forwards. Allowance
must be made in the brickwork for the expansion of the iron chamber by heat. The
said chamber may be divided into two or more longitudinal compartments, and the
outer casing may be triangular, square, or polygonal. Passages are provided for
the admission of air to either the upper or lower half of the said chamber.
the material requires to be treated with hydrogen gas the divisions must extend
the whole length of the chamber and terminate in separate ascending flues.
When
The fire-place is carried on wheels running on rails to admit of its easy removal
in the event of its becoming necessary to obtain access to the body of the roasting
chamber, or to substitute one with a hydrogen gas generator for a fire-place
without one, or vice versa.
The roasted ore receptacle being made movable, as described, gives great facility
for the removal of the ore treated.
The revolving motion is very slow, say, one revolution in five minutes, and it may
be either continuous or intermittent, the object being to subject the material under
treatment to the action of heat and atmospheric air, or heat and hydrogen gas alter-
nately.
Referring to the Drawing hereto attached, Figure 1 shows a longitudinal section
of a furnace constructed according to this Invention, in which only two longitudi-
nal compartments are inade in the roasting chamber, this being the number I prefer.
Figure 2 shows a cross section thereof.

page_text: Figure 3 shows the same roasting chamber but with a hydrogen gas generator
over the fire-place so as to supply hydrogen when required instead of atmospheric
air. Figure 4 shows a cross section thereof.
Figures 5 and 6 show cross sections of other tapering tubular roasting chambers
with more than two longitudinal compartments, being modifications of my
Invention.
an iron
A is the longitudinal division, which consists of two concave surfaces, the crown
of each meeting that of the other, while the end of spaces B is filled up by a
plate to prevent their acting as passages for the heat, air, or gas. This division is
inade of brick or brick earth, and is supported by wrought-iron plates or backing B¹,
which are pressed against the back of said division walls by means of wedges B³
screwed tight. Air holes are left at intervals to cool these wedges and plates. Cis
the fire-place, and D the opening for the entrance of the atmospheric air; these also
act as sight holes. E is the feeding shoot or hopper provided with a plate around its
mouth working against a ring. The roof of the fire-place must be built on a level
with the division so as to compel the heat to pass through that half of the revolving
roasting chamber which for the time being is the lower, although of course either
compartment can be made the heating one at pleasure by altering the arrangement
of the fire-place. In Figure 3, F is the hydrogen gas generator. In any case the
fire-place is made removable, as shown.
The mode of operation is as follows:-The material to be treated is supplied
through the shoot E, the atmospheric air holes D opened, and the fire lighted in the
fire-place C. The roasting chamber is then slowly revolved at a regular speed or
by a constant succession of partial revolutions, or it may vary in speed during each
revolution moving very slowly so long as the compartments are fairly exposed to
the action of the heat, atmosphere, or hydrogen, as the case may be, and travelling
much quicker when moving from one position to the other, or it may stop altogether
whilst being thus exposed so as to make it an intermittent motion. When the
material reaches the commencement of the divisions A it distributes itself between
the two compartments, part entering one half and part entering the other
half of the chamber, each half being alternately the upper and lower one respec-
tively. Whichever is the lower one has its contents exposed to the action of the
atmosphere.
During the process of revolution, however, both compartments are at times exposed
to the heat of the furnace. When treating sulphurets, which are difficult to roast
and easy to smelt, such as antimony sulphurets, I use a fire-place with hydrogen gas
generator, as shewn in Figure 3. I produce the gas by means of steam admitted
into the retort F containing iron, the result of which is (as is well known) the
retention of the oxygen of the steam by the iron and the setting free of the hydro-
This is then conducted into the upper half of the revolving roasting chamber,
the atmospheric air entrances D. having been previously closed. It is obvious that
the hydrogen might be conducted into the lower compartment if so desired by
altering the arrangement of the fire-place.
gen.
In the event of triangular or polygonal roasting chambers being used I should
provide them with a circular framing to support them and from which to impart
the necessary motion.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim―
First. In furnaces for roasting ores the roasting or purifying chamber of a conical
or tapering form set horizontally or nearly so, and which has imparted to it a
revolving or partially revolving motion.
Second. Dividing said conical or tapering roasting chambers into two or more
longitudinal compartments for a part or the whole of their length.
Third. Constructing such furnaces with a movable fire-place and receiver as
above described.

page_text: Fourth. Providing such movable fire-places with a hydrogen gas generator as
above described.
In witness whereof, I, the said William Robert Lake, have hereunto set my hand
and seal, this Third day of January, in the year of our Lord One thousand
eight hundred and seventy-seven.
XIZM DADT TAI-