Improvements in Apparatus for Treating Ore.
Year: 1891

page_text: Date of Application, 24th Feb., 1891-Accepted, 28th Mar., 1891
COMPLETE SPECIFICATION.
Improvements in Apparatus for Treating Ore.
I, JOHN KETCHAM HALLOWELL, Geologist, of 31, N. Ada Street, Chicago,
Illinois, United States of America, 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 :~-
The object of my invention is to provide means whereby the several successive
steps of pulverizing, separating and concentrating ore and saving the dust therefrom,
may be practised in a single continuous operation which shall be economical and
shall produce an exceptionally large yield from the ore.
In the accompanying drawings,
Figure 1 shows my improved system of apparatus diagrammatically in sectional
elevation.
Figures 2 and 3 are detail views relating to the rocking-screen concentrating
portion of my system of mechanism.
The moisture commonly contained in ore tends to increase its tenacity, sometimes
to such a degree as to prevent economical dry pulverization thereof. I overcome
this difficulty by forcing waste hot products of combustion from a furnace through
the material while being pulverized, employing to that end the apparatus A
represented in Figure 1 of the drawing, and comprising the following
construction :
A furnace, w, which may be in use for heating a steam-boiler or any other
purpose extraneous to mine, has a chimney, w', at any desired height from which
leads a conduit to a pulverizing machine of suitable construction, having a
desired number of cold-air inlets t, communication of which with the surrounding
atmosphere should be regulated by suitable removable covers. These inlets form
branches of hot-air inlet-passages u leading from the conduit w, near its permanently
closed end, into the pulverizer, and provided with dampers ². A suitable hopper a,
extending from a floor in the inclosure or house containing the furnace and
pulverizer as also the separating and concentrating mechanism hereinafter described,
communicates through a pipe al with the machine t, and affords means for feeding
to the latter the ore.
The chimney is provided with an interior false partition w², extending to a
cleaning opening w³, or hand-hole, at the base of the chimney.
At intervals along the horizontal portion of the conduit u are pockets s, each
provided with a slide-valve, as indicated, forming the removable closure for its base;
and near each pocket, at the farther side thereof in the conduit, is a damper s¹,
which I form of wire-screen.
The ore to be pulverized is fed to the machine t through the hopper . while hot
air from the chimney, which might otherwise be wasted and therefore serves my
purpose without expense for it, is forced into the pulverizer by way of the conduit
and its branches, the cold-air inlets t' being normally closed; and the hot products
of combustion from the furnace escaping into the chimney are thence directed into
conduit u by controlling the escape thereof from the top of the chimney by means
of a cover hinged to be extended over the top of the chimney and controlled from
a rope extending into accessible position.
Thus while the machine t is operating to pulverize the ore, the waste heated air
will be drawn into thorough contact with it and absorb and carry off the moisture
in its escape with the comminuted material. The screen-valves in the conduit
intercept soot, chimney dust and the like, from the furnace, causing entry thereof
into the pockets s, which may be emptied from time to time by opening the slide-
valves. Whatever of such matter is intercepted at a screen at the mouth of the

page_text: conduit where it proceeds from the chimney, falls inside the partition w², whence
it may be removed through the opening w³.
If the heat passed through the conduit and branches into the pulverizer
becomes excessive, it may be reduced, or entirely stopped, by opening to desired
extent the cover, removing the covers from the inlets to admit cold air into the
machine and closing, to desired extent, the dampers u².
In the same building with the mechanism thus far described is contained the
separating and concentrating mechanism in an apartment, 7, upon the top of which,
at the farthest extremity from the pulverizer, is a suction-fan p. The outlet
from the pulverizing machine communicates with the interior of the apartment q,
and the suction-fan tends to draw the pulverized material up an inclined course
through a screen, o, interposed in the passage, and which intercepts the insufficiently
comminuted particles, causing them to return by gravity to the chamber containing
the pulverizer whence they may be again subjected to the action of the machine t.
In the apartment are any desired number of vertical partitions n, n', nº, which rise
therein to different altitudes corresponding with the inclination of the course
indicated by the arrows, and form bins having hopper-bottoms, m, m³, m², containing
slide-valves m³. The first bin of the series has a screen m¹ over its hopper m and
communicates from near its base through an inclined pipe me with the outlet from
the pulverizer. By this construction, as the ore sufficiently pulverized to pass
through the screen o is forced along the inclined course, the heavier particles will
tend to fall below the plane thereof, and will be obstructed by the upwardly pro-
jecting partitions. Thus the heaviest particles will fall in the first bin, the finer
portions sifting through the screen me into the hopper m, and the coarser particles,
which require re-pulverization, returning through the pipe m³ to the pulverizer; the
next heavier particles fall into the hopper m'; the next heavier into the hopper m²,
and so on till, according to difference in specific gravity, all but the dust has
been separated from the product of pulverization. The dust is forced by the fan p
into the dust-collector D'hereinafter described.
Below each of the hoppers of the separating mechanism of my improved system
of apparatus is a concentrating device, B, of which all involve identically the same
construction; hence a description of one will explain each.
The material to be concentrated is fed, by opening a slide-valve in the respective
hopper of the separating mechanism, to the uppermost of a perpendicularly disposed
series of screens, the mesh of the members of which decreases in size toward the
lowermost of the series, which should be of the finest mesh. The screens slant
end wise successively in opposite directions on their supporting frame formed with
uprights between which the screens extend and which are pivotally supported to be
rocked and vibrate and thus separate the pulverized ore into its several degrees of
fineness, according to the number of screens employed of different mesh. As the
material is sifted that of too coarse a degree of trituration to pass through a screen
is automatically discharged therefrom.
The rocking frame is formed with upright bars (see Figure 2) connected at
their upper ends by a cross-bar ; and at their lower ends they are pivotally
supported in bearings k. On each upright are vertically adjustable arms
corresponding in number with the number of screens employed which the arms
serve to support. At the base of each upright, on opposite sides thereof at right-
angles to its pivot, are stops across which extend the opposite ends of an arm k?
secured transversely of the upright and permitted to rest against one of the stops
to prevent toppling of the frame when disconnected from the driving-shaft i.
Three screens are shown, though the number may be varied according to
requirement. Each comprises a rectangular frame (Figure 3) having stretched
over it woven wire h² of desired mesh. At one end of the screen is a metal plate /³
secured to the frame, and at the other end is the plate having sides converging
into a spout projecting beyond the end of the screen.
finer mesh of screens should be reinforced by diagonal
under side of the frame is secured the bottom ', slanting
The woven wire h² of the
cross wires 16. On the
downward and tapering

page_text: toward the discharge-end of the frame and having converging sides, near the
junction of which with the inclined end 49 is the outlet spout. The base of cach
screen is thus substantially synclinal; while the upper side of the frame is completely
covered by a plate having an inlet-opening at the end provided with
plate ³.
The several screens (which term includes the entire screen-structure) are
extended one below the other to incline respectively in opposite directions between
the rocking uprights 1, resting at opposite ends on the arms suitably adjusted in
relative positions for the purpose. In setting the several screens the discharge
opening of the uppermost coincides with the opening in the next lower, while
such discharge opening in the latter coincides with the inlet 12 of the lowermost
screen, the intercommunicating connection between each pair of the screens being a
flexible (canvas) pipe, of which one is also employed as the connection between
the respective hopper-bottom of the separating device and the inlet 12 to the upper-
most screen h. A receptacle such as the stand-pipe has spout-shaped inlets '
into which the discharge-spouts h from the screens lead, the screen having the
discharge-spout at its end farthest from the stand-pipe being led to an inlet 2 by a
chute *.
The driving shaft i is supported above the oscillatory screen-frame and is linked
by connecting-rods from crank-pins at its opposite ends to studs at the ends of
the cross-bar; and on the shaft is a driving-pulley to be geared to suitable
driving-power.
As the material from the separating mechanism falls upon the upper screen at its
plate 3, where the impact does no injury as it might if exerted directly on the wire-
mesh, the shaft is actuated to produce rapid rocking of the uprights, thereby
imparting to the screens one lateral oscillatory undulating motion which agitates
and induces sifting of the pulverized ore from the coarser to the finer screens, the
coarse remnant on each screen discharging from its spout into the receptacle z.
Inasmuch as the uprights are oscillated through the arcs of circles, the greatest
strain is exerted upon the uppermost screen owing to the greater weight of the
material fed to it, and the greater extent of its motion and agitation upon it of the
material. Hence it is formed the stronger; and the proportion of strength of
structure of the screens to the wear upon it under the conditions named is observed
throughout the series of screens in each rocking frame, thereby enhancing the
durability of the apparatus.
As will be understood the product of the concentration described may be reduced
according to any known or desired method.
The dust-saving apparatus D is shown to occupy a separate building (though it
may be in a separate compartment of the same building with the separating and
concentrating devices) with which the fan communicates through a conduit pl.
Generally stated the apparatus D involves a sifting chamber having an escape-
outlet and into which the dust-laden air is directed by the fan and forced upward
through sifting-cloths suspended concentrically in a collecting chamber g, accessible
through a door-way g
9
The conduit p¹ terminates in the chamber g with its mouth extending upward; and
a coney is suspended in inverted position over the conduit-mouth from a rod y¹
and is sufficiently heavy to resist displacement by the force of the blasts directed
against it from the conduit. In the upper part of the chamber are suspended
from the ceiling rectangular frames f, three of which are shown, though the number
Each
may be varied and they are supported one within the plane of the other.
frame has adjusted over it a filtering cloth, of suitable texture the cloths being
weighted at their lower edges by rods and forming several concentric cloth rooms
each closed on all sides except the base and coinciding at their common centre with
the mouth of the conduit p' which passes through one side of each of the outer ones
and is enveloped at its mouth by them to cause the dust-laden air forced by the fan p
to sift successively through all the cloths.
Below the cloths the chamberg is divided horizontally by a series of hoppers g

page_text: all leading at their discharge-ends, where they are provided with slide-valves, as
shown, into the bottom of the chamber in which the dust is collected.
The several frames are interconnected by links and the outermost frame is
connected with a side of the chamber g by a spring 3, and to the opposite side of
that frame is fastened a rope f*, leading over a pulley into accessible position from
which it may be jerked to shake the cloths f' from time to time and dislodge from
them the dust which clings to them in the sifting operation, which dust falls into
the hoppers.
At one side of the chambery is a tower E communicating therewith from above
the frames through a screen-covered opening e, at which is supported a pivotal
knocker e operated from a rope e accessible from the dust-collecting chamber
through an opening e. Within the tower from near the opening e upward are
provided to alternate with each other at opposite sides, shelves d preferably of sheet
metal pivotally supported near their centres on rods d', and all being controllable to
tip and empty them of dust-accumulations by a rope d2 secured to the outer
edge of. cach shelf and accessible from the opening
Above each hinged
shelf d is a stop-rod d³; and the upper end of the rope d' is fastened to a pivotal
knocker adapted to strike a screen c covering the tower near its upper end where
it should be protected by wire netting cagainst the entrance of birds and the like
or the accumulation of foreign matter on the screen e.
As will be apparent the dust-laden air forced by the fan p through the conduit pl
against the inverted cone y is spread in all directions causing an even distribution
thereof against the inner walls of the cloth chambers through which it is thoroughly
sifted and from the outermost of which the extremely fine particles of dust which
have passed through it are intercepted by the screen e and further on by the
screen in the tower. The matter in the tower which accumulates on the shelves
may readily be dislodged on tilting the shelves by pulling the rope d, the same
operation striking the knocker against the screen c to dislodge the material it
may hold, the knocker e¹ serving a similar purpose for the screen e; while jerking
the rope obviously dislodges the contents of the cloths f¹.
All the intercepted material from the sifting chamber is thus dropped into the
hoppers and base of the tower, whence it is admitted into the collecting chainber
below the hoppers.
While my improved system of apparatus is especially designed to have the
several devices for pulverizing, separating, concentrating and dust-saving used
successively and co-operatively, each may be used to advantage by itself to perform
its particular function, and involves novelty of construction. Hence I do not limit
my invention to the co-operative use of the several devices.
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. A device for drying ore while pulverizing it, having a pulverizing machine,
a furnace having a chimney, and a conduit connecting the pulverizing machine with
the chimney and leading the waste hot products of combustion from the furnace
into the pulverizer, substantially as described.
2. A device for drying ore while pulverizing it comprising, in combination, a
pulverizing machine t having air-inlets t, a furnace w having a chimney w¹ provided
with a false partition forming a passage in the chimney open near its base, a
cover on top of the chimney, a conduit a leading from the chimney and provided
with pockets s and internal screens st, and branches w¹ leading from the conduit
into the pulverizing machine and provided with dampers 2, substantially as
described.
3. An ore separating device comprising in combination with an inclosure con-
taining a pulverizer t, bins formed with partitions in the inclosure extended suc-
cessively higher from the pulverizer to define a gradually rising plane, an
exhaust-fan communicating with the inclosure containing the partitions near the

page_text: upper end of the inclined plane, a screen m³ in the lowermost bin, and a retura-
pipe m' leading from the screen m¹ back to the pulverizer, substantially as
described.
4. An ore concentrating device having a rocking frame formed with uprights!
pivotally supported at their bases and each provided with supporting arms, and
intercommunicating covered screens adapted to discharge from their ends and
supported to extend, one above the other lengthwise between the uprights on the
said arms to be rocked laterally in the plunes of the arcs described by the rocking
uprights, and inclining successively in opposite directions, substantially as
described.
5. An ore concentrating device comprising in combination a rocking frame formed.
of the pivotally supported uprights I connected together at their upper ends, a
driving-shaft i conected with the frame and adapted to be connected with suitable
driving power, supporting arms and stop-arms on the uprights, stops k¹ at the
bases of the uprights for the arms & intercommunicating inclosed screens supported
to extend between the uprights on the arms and inclining successively in opposite
directions, and a receptacle into which the screens discharge, substantially as
described.
P
6. A device for collecting the dust of pulverized ore, having, in combination,
with a fan communicating with the dust-supply, a chamber g into which the fan
discharges through a conduit p¹ and containing a series of hoppers g' dividing it
into an upper sifting chamber provided with an escape outlet and a lower collecting
chamber, the conduit p' leading into the sifting chamber and discharging therein in
an upward direction, and a series of cloth covered frames / suspended in the sifting-
chamber over the month of the conduit, substantially es described.
7. A device for collecting the dust of pulverized ore, comprising, in combination
with a fan p communicating with the dust supply, a chamber g into which the fan
discharges through a conduit p and containing a series of hoppers y dividing it
into an upper sifting chamber and a lower collecting chamber, the conduit pleading
into the sifting chamber and discharging therein in an upward direction, a series
of connected cloth-covered spring-controlled frames suspended over the mouth of
the conduit, and a screen-covered tower E communicating through a screen-covered
opening e with the sifting chamber and containing a knocker and alternating
hinged shelves d connected together and with said knocker, and a knocker e¹ for the
screen e, substantially as described.
8. An apparatus for treating ore to successively pulverize, separate and concen-
trate it and save the dust therefrom, comprising in combination an inclosure
containing a pulverizer communicating with the chimney of a furnace w', a separator
having a compartment into which the pulverizer discharges and containing parti-
tions rising to successively increasing altitudes and forming a series of bins adapted
to discharge from their bases, a fan p above the final bin operating to draw the
material from the pulverizer up an inclined course, a rocking-screen concentrator B
below the base of each bin, and a dust-saving apparatus D into which the fan
discharges, the whole being constructed and arranged to operate substantially as
described.
9. An apparatus for treating ore to successively pulverize, separate and concen-
trate it and save the dust therefrom, comprising, in combination, an inclosure
containing a pulverizer t, a furnace w with the chimney w¹ of which the pulverizer
communicates controllably through a conduit u having pockets s, and containing
screen dampers, and through branches u' leading from the conduit and having
cold-air inlets t, a separator having a compartment into which the pulverizer
discharges and containing partitions rising to successively increasing altitudes and
forming a series of bins having hopper-bottoms, the bin nearest the pulverizer
having a screen over its hopper and a return pipe leading to the pulverizer, a fan
above the final bin of the series operating to draw the material from the pulverizer
up an inclined course, a rocking-screen concentrator B below each said bin and
comprising intercommunicating screens supported one above the other to slant

page_text: alternately in opposite directions and extend lengthwise between uprights 1, pivoted
at their lower ends to rock the screens endwise, means for rocking the uprights,
and a receptacle into which each screen discharges, and a dust-saving apparatus D,
comprising a compartment y divided internally by hoppers g' forming below them a
dust-collecting chamber and having suspended above the hoppers concentric sifting
cloths on interconnected frames adapted to be jolted, a tower E communicating
with the chamber g above the cloths and containing tilting shelves d and knockers
for screens e and operated from suitable ropes, a conduit p¹ leading from the fan
into the chamber below the sifting cloths and having an upward extending mouth,
and a distributing cone y, suspended over the mouth of the conduit, substantially as
described.
Dated this 24th day of February 1891.
W. P. THOMPSON & BOULT,
Agents for the Applicant.