IMPROVEMENTS IN APPARATUS USED FOR CALCINING AND ROASTING COPPER AND OTHER ORES, AND SUBSTANCES CONTAINING SULPHUR
Year: 1865

page_text: LETTERS PATENT to Thomas Bell and Thomas Lesslie Gregson Bell, of
Plaistow, in the County of Essex, for the Invention of "IMPROVEMENTS IN
APPARATUS USED FOR CALCINING AND ROASTING COPPER AND OTHER ORES, AND
SUBSTANCES CONTAINING SULPHUR."
Sealed the 9th March 1866, and dated the 14th September 1865.
PROVISIONAL SPECIFICATION left by the said Thomas Bell and Thomas
Lesslie Gregson Bell at the Office of the Commissioners of Patents, with
their Petition, on the 14th September 1865.
We, THOMAS BELL and THOMAS LESSLLE GREGSON BELL, of Plaistow, in
the County of Essex, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN APPARATUS USED FOR CALCINING AND ROASTING COPPER AND
OTHER ORES, AND SUBSTANCES CONTAINING SULPHUR," to be as follows:-
This Invention has for its object improvements in apparatus used for
calcining and roasting copper and other ores and substances containing
sulphur. For these purposes a rotating retort is employed, which is set in an
inclined position within a chamber wherein artificial heat may be applied to
the exterior of the retort should the material or substance which is being
treated not contain sufficient sulphur to maintain the combustion. On the
interior of the retort there are longitudinal ridges, so that as the retort is
caused to revolve slowly, the pulverized ore or substance as it descends in the

page_text: retort becomes turned over or changed in position, so as to present fresh
surfaces to the action of the current of atmospheric air which is caused to
pass through the retort. The lower end of the retort passes out of the
chamber, and delivers the calcined or roasted ore or substance into another
chamber or receiver, which has by preference an inclined floor. This receiving
chamber has openings for the passage of atmospheric air both above and
below the calcined or roasted ore in the chamber or receiver, and slides or
valves are applied to the openings or air passages to regulate the supply of air
into the chamber and to the interior of the retort. The other or upper end of
the retort also passes out of the chamber in which it is set, and has a hopper
applied to it, so as to deliver a constant and regulated stream of the pulverized
ore or substance into the revolving retort. This upper end of the retort is
connected by a pipe or passage with a sulphuric acid chamber, and by this
pipe the sulphurous acid evolved is conveyed away, and it is converted in the
chamber into sulphuric acid.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Bell and Thomas Lesslie Gregson Bell in the Great
Seal Patent Office on the 14th March 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, We, THOMAS
BELL and THOMAS LESSLIE GREGSON BELL, of Plaistow, in the County of
Essex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of September, in the year of our
Lord One thousand eight hundred and sixty-five, in the twenty-ninth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto us, the said Thomas Bell and Thomas Lesslie Gregson Bell, Her
special licence that we, the said Thomas Bell and Thomas Lesslie Gregson
Bell, our executors, administrators, and assigns, or such others as we, the
said Thomas Bell and Thomas Lesslie Gregson Bell, executors, adminis-
trators, and assigns, should at any time agree with, and no others, from time
to time and at 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 APPARATUS USED FOR CALCINING AND ROASTING
COPPER AND OTHER ORES, AND SUBSTANCES CONTAINING SULPKUE," upon the con-
dition (amongst others) that we, the said Thomas Bell and Thomas Lesslie

page_text: Gregson Bell, our executors or administrators, by an instrument in writing
under our or their hands and seals, or under the hands and seals of one of us or
them, should particularly describe and ascertain the nature of the said Inven-
tion, and in what manner 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 Thomas Bell, on behalf of myself and
the said Thomas Lesslie Gregson Bell, do hereby declare the nature of the
said Invention, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement
thereof, that is to say :-
This Invention has for its object improvements in apparatus used for
calcining and roasting copper and other ores and substances containing
sulphur. For these purposes a rotating retort is employed, which is set in an
inclined position within a chamber, wherein heat may be applied to the
exterior of the retort, which is caused to revolve slowly, so that the pulverized
ore or substance as it descends in the retort becomes turned over or changed
in position, so as to present fresh surfaces to the action of the current of.
atmospheric air, which is caused to pass through the retort. The lower end
of the retort passes out of the chamber and delivers the calcined or roasted
ore or substance into another chamber or receiver, which has, by preference,
an inclined floor. This receiving chamber has openings for the passage of
atmospheric air, and slides or valves are applied to the openings or air passages
to regulate the supply of air into the chamber and to the interior of the retort.
The other or upper end of the retort also passes out of the chamber in which
it is set, and has a hopper applied to it, so as to deliver a constant and regulated
stream of the pulverized ore or substance into the revolving retort. This
upper end of the retort is connected by a pipe or passage with a sulphuric
acid chamber, and by this pipe the sulphurous acid evolved is conveyed away,
and it is converted in the chamber into sulphuric acid.
And in order that our said Invention may be most fully understood and
readily carried into effect, we will proceed to describe the Drawings hereunto
annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a longitudinal section, Figure 2 is a transverse section, and
Figure 3 is a front view partly in section of apparatus constructed according
to our Invention.
a, a, is a chamber heated by a fire on the fire bars 6, over which an arch of
fire-brick is turned; and in this arch perforations or pigeon holes are formed,

page_text: through which the heat escapes to heat the chamber uniformly from end to
end; c, c, are cast-iron conical retorts, but they might, if desired, be cylin-
drical so long as they are inclined. These retorts are, say, 3 ft. 6 ins. in
diameter, and inclined slightly at the bottom from front to back, and are lined
by preference with fire-brick, as is shewn. There may be also longitudinal
ridges running from end to end of the interior of each retort; but with 'most
materials these ridges are unnecessary, as the rotation of the retort alone is
sufficient to turn the material constantly over and over; d, d, are friction
pulleys, on which the retort rests at its two ends; c³, c', are worm wheels on
the front of the retorts; they gear with worms e, e, on the axis e¹; this axis
may be driven in any convenient manner at a velocity which can be regulated
at will, so as to pass the material through the retorts at a greater or less speed,
and the workman' will adjust the velocity of the axis e¹ until the ore or sulphur
material is discharged from the retort roasted to the extent desired. The ore
or material discharged by the retorts is received into a chamber f, in which is
a grated floor g, from beneath which the roasted ore or material is drawn from
time to time; h, h, are openings, furnished with regulating doors, by means of
which regulated currents of air may be admitted to the chamber f, to pass
from thence through the retorts; i, i, are passages by which the sulphurous
acid formed by the burning off of the sulphur from the ore or mineral is
conducted to sulphuric acid chambers situated at a higher level, so that there
may always be a sufficient draft of air through the retorts from back to front;
k, k, are hoppers, into which the pulverized ore or material to be roasted is
fed, and from these it descends into the retort at a speed regulated by the
rotation of the small rollers l, l, on which are cross arms, as is shewn; these
rollers receive motion from the axis e' with which they are geared by pinions.
This apparatus is applicable for roasting copper, tin, lead, zinc, and other ores
containing sulphur, also artificial pyrites (obtained by smelting soda waste
with oxide of iron or other processes), and also other materials containing
sulphur.
Having thus described the nature of our said Invention, and the manner
of performing the same, we would have it understood that we do not confine
ourselves to the exact details described; but we claim the combination of
apparatus as herein described for calcining and roasting copper, tin, and other
ores and substances containing sulphur. The said apparatus consisting
essentially of an ordinary sulphuric acid chamber combined with a rotating
retort, the bottom of which is inclined, and into which the material is fed
continuously at one end, and discharged at the other, provision being made for
a regulated supply of air being maintained in the retort, so that the

page_text: sulphurous acid formed in the calcining and roasting operation may be
led into the said sulphuric acid chamber, and there converted into sul-
phuric acid.
In witness whereof, I, the said Thomas Bell, have hereunto set my hand
and seal, this Thirteenth day of March, in the year of our Lord One™
thousand eight hundred and sixty-six.