IMPROVEMENTS IN THE TREATMENT AND SEPARATION OF ORES AND OTHER SUBSTANCES, AND IN THE APPARATUS EMPLOYED THEREIN.
Year: 1877

page_text: LETTERS PATENT to Francis John Bolton, commonly called Frank Bolton, of 4,
Broad Sanctuary, Westminster, Major, late 12th Regiment, for the Invention
of "IMPROVEMENTS IN THE TREATMENT AND SEPARATION OF ORES AND OTHER
SUBSTANCES, AND IN THE APPARATUS EMPLOYED THEREIN.'
"
Sealed the 29th December 1877, and dated the 7th July 1877,
PROVISIONAL SPECIFICATION left by the said Francis John Bolton at the
Office of the Commissioners of Patents on the 7th July 1877.
FRANCIS JOHN BOLTON, commonly called Frank Bolton, of 4, Broad Sanctuary,
Westminster, Major, late 12th Regiment. "IMPROVEMENTS IN THE TREATMENT AND
SEPARATION OF ORES AND OTHER SUBSTANCES, AND IN THE APPARATUS EMPLOYED
THEREIN."
My Invention has for its object the separation of iron and minerals containing
iron from other substances with which they are mingled, but is more particularly
applicable to the separation of iron and copper pyrites from blende and other
substances.
The first part of my Invention consists in calcining or roasting mixed ores con-
taining pyrites in any suitable form of calciner, furnace, retort, or muffle in an
atmosphere of superheated steam, either with or without the admission of air or
gases, by which means I firstly convert the sulphide of iron or the iron in the
mingled sulphides of iron and copper into a highly magnetic oxide; and, secondly,
prevent almost entirely the formation of soluble sulphates of copper and zinc, which
are partly formed when the calcination is performed in atmospheric air, and which
would enter into solution in any subsequent treatment with water.
رو
The second part of my Invention relates to improvements in what are known as
magnetic separators," and consists,-
Istly. In employing a grooved form of electro-magnet in the construction of the
magnetic drum or cylinder, or endless band or chain of magnets, by which means
the attracting surfaces are greatly increased.

page_text: Secondly. In disengaging the particles of magnetic ore from the poles of the
electro-magnets by means of a reversed current of electricity.
Thirdly. In employing a blowing apparatus or a steam jet or rose of water, or of
imparting a shaking or jigging motion to the magnetic separator, in order to
disengage any particles of iron magnetic ore which may be mechanically mingled
with the magnetic particles adhering to the magnets.
It is obvious that the second part of my Invention is not only applicable to the
treatment of the ores referred to in the first part, but also to the separation of iron
from any substances in which it exists in a magnetic state, or has artificially been con-
verted into a magnetic state.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Francis John Bolton in the Great Seal Patent Office on the 7th January
1878.
FRANCIS JOHN BOLTON, commonly called Frank Bolton, of 4, Broad Sanctuary,
Westminster, Major, late 12th Regiment. "IMPROVEMENTS IN THE TREATMENT AND
SEPARATION OF ORES AND OTHER SUBSTANCES, AND IN THE APPARATUS EMPLOYED
THEREIN."
My said Invention has for its object the separation of iron and minerals con-
taining iron from other substances with which they are mingled, but is more
particularly applicable to the separation of iron and copper pyrites from blende and
other substances.
And it consists in calcining or roasting mixed ores containing pyrites in any
suitable form of calciner furnace, retort, or muffle in an atmosphere of superheated
steam, either with or without the admission of air or gases, by which means I firstly
convert the sulphide of iron or the iron in the mingled sulphides of iron and copper
into a highly magnetic oxide; and, secondly, prevent almost entirely the formation
of soluble sulphates of copper and zinc, which are partly formed when the calcina-
tion is performed in atmospheric air, and which would enter into solution in any
subsequent treatment with water.
In carrying out my Invention the mineral to be operated upon, after being
reduced to a convenient size for separation, is placed in a calciner or calcining
furnace of any suitable form, and heated in the ordinary manner, but in lieu of
allowing a large volume of undecomposed air, that is to say, air whose oxygen has
not been combined with the carbon of the fuel, to enter the calcining chamber, as is
done in the ordinary methods of calcination, I either exclude atmospheric, air
altogether, in which case I employ a close or muffle form of furnace, or I reduce
and regulate its admission as found most expedient, and I cause a jet or jets of dry
superheated steam to be introduced into the chamber of the furnace, by which
means the whole or a part of the iron present is converted into the black or magnetic
oxide. The particles of magnetic ore are then separated from the non-magnetic
particles by the employment of a "magnetic separator" of any usual or suitable
construction.
If, as is sometimes the case, especially when the material under treatment is in a
very fine state of division, the force of gravity is not sufficient to cause the non-
magnetic particles to disengage themselves, and fall from the magnets, I cause steam,

page_text: air, or water to play upon the magnetic surfaces with sufficient force and volume to
remove the non-magnetic particles but not so violently as to overcome the adhesion
of the magnetic particles.
Having now described and particularly ascertained the nature of my said Inven-
tion, and the manner in which the same is or may be used or carried into effect, I
would observe in conclusion that 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. Roasting or calcining minerals in an atmosphere wholly or partially of
superheated steam for the purpose of enabling the separation of the resulting
products to be subsequently effected by magnetic agency, substantially as herein-
before described.
Second. Effecting the removal of the non-magnetic particles from the magnetic
surfaces of the separator, substantially in the manner herein-before described.
In witness whereof, I, the said Francis John Bolton, commonly called Frank
Bolton, have to this my Specification set my hand and seal, this Fourth day
of January, One thousand eight hundred and seventy-eight.
FRAS. JNO. BOLTON. (L.S.)