Improvements relating to the Separation of Magnetic Ores from Phosphorus and other Impurities and to Apparatus therefor.
Year: 1889

page_text: COMPLETE STECIFICATION.
[Communicated from abroad by CLINTON MANNING BALL, of 181 A Street, in the
City of Boston, County of Suffolk, and State of Massachusetts, Electrician and
.Manufacturer of Electrical Appliances, SHELDON NORTON, of Hokendauqua, in the
County of Lehigh, and State of Pennsylvania, Civil and Mining Engineer, and
ALEXANDER THOMAS PORTER, of 2, Russell Place, in the City of West Troy,
County of Albany, and State of New York, Contractor, all in the United States
of America.]
Improvements relating to the Separation of Magnetic Ores from
Phosphorus and other Impurities and to Apparatus therefor.
I, HENRY HARRIS LAKE of the firm of Haseltine, Lake & Co., Patent Agents,
Southampton Buildings, in the County of Middlesex, 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:-
This invention relates to a novel method or process of and apparatus for separating
magnetic ores from the impurities with which they are generally found associated,
such as phosphorous, sulphur in the form of pyrites, and the like.
Briefly the invention consists in forcibly causing the tumbling or rolling of the
particles of crushed ore through a compound magnetic field of alternating polarity
with or without the application of a current of air; and the invention further
consists in the specific processes and steps hereinafter described.
The invention further consists in an apparatus adapted to forcibly cause the
tumbling or rolling of the particles of material through a compound magnetic field
of alternating polarity, with or without the application of a current of air, and the
invention further consists in the arrangement or construction of devices for the fore-
going purposes all substantially as hereinafter fully described.
In the accompanying drawing
Fig. 1 is a vertical section of a complete apparatus constructed in accordance with
the principles of my invention;
Fig. 1 is a diagram illustrating the principle;
Fig. 2 is a sectional elevation of a modified form of the apparatus ;
Fig. 2 is a face view of the compound magnet illustrated in three different modes
of construction;
Fig. 3 is a longitudinal vertical section; and
Fig. 4 is a transverse vertical section of another modified form of the apparatus
constructed in accordance with my invention.
Referring now to Fig. 1: I construct the hopper 1 having an adjustable gate 2
adapted to spread the ore and gangue uniformly and to an even depth over an
inclined apron 3, which feeds into a vertical chute 4 whose lower end is connected
with the inlet of a rotary fan or blower 5 which may be conveniently operated by the
belt 6 and pulley 7 on the countershaft 14. Situated on a frame work of the structure
are the two parallel shafts 8, 9, and these carry the drums 10 and 11 over which is
passed an endless belt 12, or screen of preferably non-magnetic material, drum 11
being driven positively by means of a belt from any suitable source of power. Both
or either of the ends of the apparatus between the drums 10 and 11 and the face of
the inclined apron 3 may be open to the atmosphere so that in the operation of the
blower 5 currents of air are induced at these points and deflected downwardly into
cbute 4, as indicated by arrows in the figure. In the space between the drums 10
and 11 I place a series of magnets M, M 2, M3, M 4, and these magnets may be

page_text: either permanent or electro-magnets, and they are so arranged as to have their free
poles in close proximity to the inner face of belt 12 next the inclined apron 3. The
free poles are arranged in alternation as to polarity, that is, if the first pole is north
the second is south, the third north and the fourth south, and so on throughout the
series which may be of any desired number. The shape of the poles may vary
according to the will of the designer and may be either elongated to the full width of
the belt or to a less extent, or may be made up in groups of circular magnets, all of
which forms are indicated at Fig. 2".
3
The operation will be as follows: The ore and gangue passing down the apron
comes within the attractive influence of the first pole of the magnetic system and all
magnetic particles contained in the body of ore are immediately attracted and held
against the moving belt 12 which on this side is moving downwardly, as indicated
by the large arrow. All the magnetic particles are attracted first to the first pole but
as the belt compels them to move forward towards the second pole their positions are
reversed and leaving the second pole for the third pole their positions are again
reversed and so on past the series of magnets in succession so that all the magnetic
particles are not merely caused to adhere against the face of the belt but as they pass
along are compelled to, as it were, tumble or turn end for end, and in this manner are
very thoroughly agitated and their friction upon one another and upon the belt along
with the mechanical agitation effected by the alternations of magnetic polarity result
in a most thorough cleansing of the magnetic particles from all dust or other im-
purities which would otherwise cling to them. The peculiar action upon the magnetic
particles is graphically illustrated in Fig. 1a, where for the purpose of clearness a
single particle is shown in its successive positions as it travels past the alternating
poles of the magnetic system, the particle being exaggerated in size in order to make
the action clear. On inspection of this figure it will be observed that as the particle
first approaches the magnetic system it becomes polarized by induction and
one end becomes attracted more strongly than the other owing to this induced
polarity and as it passes such pole it stands on end in accordance with the
well known phenomena of the lines of force in magnetic substances. As it is
carried forcibly past this pole its outer and free end tends towards the next
pole of the magnetic field and midway between the two, the position of the particle is
parallel with the belt and when it reaches the second magnetic pole it again stands on
end, but this time on the opposite end from that on which it stood at the last stage.
And so on throughout the entire series of poles of the compound magnetic field, the
magnetic particle is drawn by the belt and at the same time compelled by the
magnetic attractions to tumble end over end, as it were, a sufficient number of times
to absolutely cleanse it of all foreign substances and dust which might be clinging to
its exterior.
As the gangue approaches the chute 4 most of the unmagnetizable portions fall into
the chute and are carried away by the current of air produced by the blower 5, and
as a final step towards perfectly cleansing the magnetic particles which are now past
the chute and are ready to be delivered, the induced current of air upwardly past
the lower end of apron 3 has the effect of blowing away the last traces of dust and
all other impurities which may possibly be still clinging to the particles of magnetic ore,
after which the belt carries them outside the magnetic field and as they are no longer
attracted they fall on the lower end of apron 3 and thus not merely separated from
the gangue but also perfectly cleaned. In Fig. 2 the inclined apron is replaced by
an endless belt 15 travelling on the drums 16 and supported by the rollers 17 the
hopper 1 and the gate 2 remaining substantially as in the previous construction. In
this case the belt 12 and drums 10 and 11 are arranged horizontally so that the
underside of the belt passes along in close proximity to belt 15 and the
magnets M, M 2 etc. are arranged as before between the two drums 10 and 11 with
their free poles in close proximity to the back of the belt 12. The hopper 4 remains.
unchanged as also the blower 5, but I have placed the guide plate 18, which forms the
front wall of the closed receiving chamber 22, in such position as to form a sort of

page_text: flat nozzle at the upper rear edge of hopper 4, so as to more energetically direct the
current of air induced at that point by the action of the blower drawing air through
the hopper 4 downwardly, and cause it to impinge upon the moving body of ore
before the latter is carried out of the field of magnetic attraction; and to avoid
carrying back the smaller particles of magnetic ore by the air current, and to prevent
their accumulation at the discharge, the ore is received into the closed chamber 22,
from which the flow of cleaned ore may be regulated by the sliding gate 23.
In Figs. 3 and 4 the form is again slightly modified and in this case the hopper 1
delivers into a narrow vertical chute 19 in which is arranged to rotate a disc of
diamagnetic material 20 carried by the shaft 21, and on the side opposite that in
which chute 19 is located we place the group of magnets M, M2, M3, M4. The
chute 4 is located at the lower end of the apparatus similarly to the previous forms
and the blower 5 is situated so as to act precisely the same as in the said previous
forms. While somewhat changed in form and arrangement all the foregoing modifi-
cations operate on precisely the same principles and effect the same results.
Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed, as communicated to me by my
foreign Correspondents I declare that what I claim is :
1st. The process of separating iron or its ore from impurities consisting in forcing
it in a state of division past a succession of two or more magnetic poles of
alternating polarity, whereby the particles are forcibly caused to tumble or rotate
end for end.
2nd. The process of separating iron or its-ore from impurities consisting in forcing
it in a state of division past a succession of two or more magnetic poles of
alternating polarity, while interposing a non-magnetic screen between the ore and
the poles.
3rd. The process of separating iron or its ore from impurities consisting in forcing
it in a divided state past a succession of magnetic poles of alternating polarity while
subjecting the material to the action of a current of air.
4th. The process of separating magnetic ore from its accompanying impurities
consisting in causing the movement of the particles of ore through a magnetic field
in a given direction by interposing a moving non-magnetic screen between the ore
and the magnet producing such field and at the same time subjecting the body of ore
and gangue to the action of a current or currents of air in an opposite direction to
that of the ore.
5th. The process of separating magnetic ore from its accompanying impurities
consisting in causing the movement of the particles of ore through a magnetic field,
while interposing a moving non-magnetic screen between the ore and the magnet
producing such field, and at the same time subjecting the ore and gangue to the action
of a current of air.
6th. The ore separator comprising a group of magnets of alternating polarity in
combination with means for forcibly conveying the ore past the said magnets
successively without contact therewith.
7th. The ore separator comprising in combination a group of magnets of alter-
nating polarity, a travelling screen adapted to move across the poles of said
magnets, and means for delivering the ore in proximity to the screen.
8th. The ore separator comprising in combination a group of magnets of alter-
nating polarity, a travelling screen of diamagnetic material adapted to move across
the poles of said magnets, and means for delivering the ore in proximity to
the screen.
9th. The ore separator comprising in combination, a group of magnets of alter-
nating polarity, a travelling diamagnetic screen adapted to move across the
poles of said magnets, means for delivering the ore to the outer side of said
screen and means for forcing a current of air through the space traversed by the
ore as it passes the magnet poles.

page_text: 10th. The ore separator comprising in combination a group of magnets of
alternating polarity, a travelling diamagnetic screen adapted to move across the
poles of said magnets and an apron adapted to confine the ore within inductive range
of said magnets and deliver it in close proximity to said screen.
Dated this o9th day of M... 1980
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicants.