Improved Method and Apparatus for Separating, Amalgamating, and Concentrating Ōres.
Year: 1893

page_text: Date of Application, 18th July, 1893-Accepted, 18th Aug., 1894
COMPLETE SPECIFICATION.
Improved Method and Apparatus for Separating, Amalgamating, and
Concentrating Ōres.
I, HENRY EDWARD KITTON, of 144 Barrow Street Brunswick in the Colony
of Victoria, Engineer (recently of 26 Milton Street West Melbourne) do hereby
declare the nature of my invention and in what manner the same is to be
performed, to be particularly described and ascertained, in and by the following
statement:
My invention consists of the application of centrifugal force, to the separation
and saving of gold, and to the concentration of metal-bearing material, by the
methods and in the manner shown, in the accompanying sheets of drawings, marked
Sheet I. II & III and as set forth and stated in this following statement and
description.
Fig. I. shows a half sectional elevation of my machine.
Fig. II. shows a half elevation of the machine.
The plan of my machine is (generally) circular.
Referring to Figs. 1 and II, A is a steel or iron vessel (virtually a cylinder) of
the general outline shown, attached to and revolving with the vertical shaft B.
C is a distributing dome, likewise attached to and working with the shaft B, but is
readily removable by taking off the cap D. C has on its upper and outer surface,
slightly raised involutes; the cap D is screwed to the end of the shaft B, and
contains a small lock to prevent its surreptitious removal. E is a cap or cover
attached to A, and carries a removable hard cast iron wearing ring F.
Gis a light stamped iron bottomless pan, supported in the ring H.
H may be carried or supported by light brackets springing from the base of the
machine, or may be supported from the staging erected for other purposes near the
machine. The pan G contains a sieve or fine grating J, with an unperforated
conically raised centre. This sieve is attached to a light iron ring, readily
removable from the pan G.
K is a cast iron stand or support for the machine, and carries in its upper part
the bearing L, and below, the bearing M. These two bearings are both supplied
with oil, at their lower ends. The overflow oil is carried from both bearings, to a
drip pan as indicated (below) by dotted lines. The oiling of the top bearing is
effected, by feeding the oil with an ordinary syphon feeder, into the ring running
round the outer lower end of the bearing L, and by inlet holes to a fine spiral
groove, passing up the inside of the bearing L, and overflowing its top into the
upper annular cavity, from which a small pipe (not shown in the drawing) passes
to the drip pan below, giving evidence, to the man in attendance, that the oiling is
being effected.
The upper bearing L is supported in the base K, by means of a heavy india-
rubber ring, (shown towards its top) and a pair of check nuts below.
The shaft B is set into the bearing M, and is tipped at its lower end with a
replacable hard steel pin, resting on a hard steel ball, free to revolve in the
bearing M. The ball supported on a pin in the upper end of a set screw,
to the bearing M by means of a locknut.
fixed
N shows a light rope pulley, for imparting motion to the shaft B. The motion
however may be imparted by gearing, or any other means, preferably, where
engine power is not readily available, by means of a steam turbine attached to
the shaft.
O is a circular mercury channel, running round in the casting K, having a slight
depression towards a locked iron outlet pipe.

page_text: P with its domeshaped lower wing, is a cover for the channel O, and is movable
upwards and downwards by means of raising rods (shown by dotted lines), but is
locked to prevent its rising higher than necessary to perform its functions. The
raising rods pass through holes in the casting K, and are each connected to a
lever (dotted).
These levers are weighted to nearly balance on the fulcrum, and are actuated
simultaneously by hand by one common lever. They are also actuated by a small
set of sensitive governors driven by the shaft B. Q is a light plate iron outer
circular channel the bottom having a deep fall to the outlet R, Fig. II.
5
The casing Q is supported by the casting K, and may be moved round to bring 1
the outlet R to any point of the compass. The bottom of the channel Q has across
the widened inner end of the projecting outlet R, depressions, into which mercury
troughs may be introduced as "ripples." S is a movable domeshaped cover for
the channel Q, and carries on its inside as shown by slight thickening in the
S may
sectioning, a replacable impact or wearing ring. The channel Q and its cap
in certain cases (to be explained further on), be removed and replaced by two or
more somewhat similar channels. The dotted lines T rising from P and passing
upwards through guide holes in the ring H, represent light iron rods, triangular in
section near their bases, with one angle turned to meet the tangent passing from
the vessel A in the direction of its motion to cut the rod. U is a turned groove
of the section shown passing round the inside of the vessel A. V shows a
replacable hard cast iron wearing ring.
✗ is a series of outlets nearly contiguous to each other in a horizontal plane,
and passing from inside outwards, slightly to meet the direction in which the
machine revolves. The shaft B carries a small worm screw not shown in the
drawing, into gear with which, a small wheel may be swung at pleasure, as a speed
indicator.
The working of the machine, is as follows:
The oiling being in a perfect condition, motive power is applied to revolve the
shaft B, which is, as in all centrifugal machinery, gradually brought up to its
working speed. The working speed may be varied to suit different classes of
material, and to any extent without affecting the principles of
my
invention.
The vessel represented at A is arranged for about twenty revolutions per second,
but can be run at a much higher or considerably lower speed, without altering its
shape in any degree.
When the speed is normal, which is readily tested by the speed indicator, a little
clean water is poured into the pan G, which at once passes outwards and downwards
between the parts marked C and E, and into the annular shaped space between the
outer surface of C, and the inner surface of A, where it remains filling up the
groove U, and the outer boundary of the space between A and C, until its inner
surface forms a paraboloid of revolution passing through the inner edge of the
ring V, and upwards nearly vertically, till its upper end meets the lower horizonta
bounding surface, of the upper part of A, as shown in section by the dotted line
any further addition of water overflows the lip of the ring V, and passes out and
tangentially across the cover P, into the channel Q, and through the outlet R. A
weighed quantity of mercury, sufficient to nearly displace the water in the machine
is now gently poured into the bottom of the pan G, from which it passes down int
the space occupied by the water, the water passing outwards across P, into Q a
before.
The screen J is now placed in the pan G, but is only intended as a safeguar
against the passage of large stones into the machine; and is of a mesh large enoug
to freely pass the grade of stuff to be worked.
In the case of material which carries a considerable proportion of large stone
such as coarse alluvial tailings, it must be screened as a preparatory process. T
material may be fed into the pan G by any fairly regular mode of feed; such a
water carriage,"
""belt and buckets," centrifugal pump," etc.
3966
Where water is scarce, the machine may be worked dry, in which case t

page_text: involutes on the upper surface of C, and the lower surface of E, are more
pronounced and form an air fan, to assist the passage of the material through the
machine. The material fed into the pan G, follows the course as described for
the water, viz.: onto the dome or distributor C, and. outwards and downwards,
between the upper surface of C and the lower surface E, and on to the paraboloidic
surface of the mercury, immediately below F, this is what I term the "feeding-
point," and any method of feeding, or bringing about contact between the material
and the paraboloidical mercurial surface which involves the passage of the material
downwards, towards an outlet at a lower level than its point of first contact with
the mercurial surface-I term a "top feed," as entirely distinct from machines,
which have their "feeding point" at a lower level than their outlet. In my
machine the material passes downwards from the feeding point near F, to the outlet
near V, and during its passage is under the influence of centrifugal force which
drives any particles, of a greater specific gravity than mercury, through the
mercury to the inner surface of A, where they are held quite irrespective of
amalgamation.
The waste material after leaving the mercurial surface, passes through the
outlets X across P, into the channel Q, and away through the outlet R. In
treating any material, (especially in dry working,) which carries a proportion of
pyrites, or other heavy material, worthy of special treatment, the channel Q is
made somewhat wider, with one or more divisions, according to the objects sought,
running down to the bottom and having seperate outlets, so that the heavy material
from the outermost divisions, may be retained for after treatment.
When the machine is to be stopped and has dropped considerably below its
normal velocity, the governors act on the dotted lever, divert the feed supply by
raising the dotted rods T, raise also the cover P, before the mercury commences to
leave its position, so that, on doing so the mercury passes out and against the
underside of the lower domeshaped wing of P, and is diverted into the channel O,
where it remains locked in safety until required. The objects of the groove U,
are to retain the amalgam in greater security, until
"clean up
a
is required when
the amalgam may be taken out and placed direct into the retort, without the
necessity of passing through chamois or canvas. When the machine is driven by
a steam turbine, the governors which act on the cover P are also made to act
earlier on the steam supply to the turbine. My machine may be varied in shape
or proportion without affecting my invention. The drawing represents a machine
with a mercurial diameter of sixteen inches.
"
Definition By the terms "paraboloid of revolution," "paraboloidic mercurial
surface" "mercurial paraboloid ""paraboloidic surface "-I refer to, and include
all forms which mercury may assume, while under the influence of "centrifugal
force," "gravity," and the varying influences of "shape of containing vessel
"quantity and manner of feeding," and all influences which may modify the effect
and 66
of “centrifugal force" ‘gravity." Or in other words :-The term
paraboloid is used to designate all the forms taken by mercury, while subject to
the forces that may be brought to bear on it, when used in a revolving vessel.
66
"
By the term "top feed I mean, any method whatsoever of bringing about
contact between the gold (or heavy metal) bearing substance, and the paraboloidic
mercurial surface, which involves the passage of the gold-bearing substance down-
wards, after its first contact with the paraboloidic surface, in short "the top feed
embraces any method in which the outlet for the gold-bearing substance, is below,
or nearer to the centre of the earth, than the position occupied by the mercury
employed.
The advantages of "the top feed "--over the old bottom feed, can be best
exemplified, by a diagramatic explanation.
In Figure III the curve a bg c, may be taken, as typical of the vertical section
of the mercury, while under the action of gravity and centrifugal force, in any of
the old forms of centrifugal gold savers, which have their "feeding point" (as
defined previously) at a lower level than their outlet.

page_text: Let b, be the "feeding-point -Now in order to guard against loss of mercury, by
unsteadiness or slight variation in the speed, there must be some small recessment of
safety such as c d, if now an addition of mercury or, say water, be added, just to
overflow at d, the section of the new curve is represented by the curve dhe f, and
is in reality, simply the old curve c gba, pushed up through a distance af. Now
it is obvious that e b, is greater than d c, and from the properties of a parabola,
eb must be some multiple-greater than unity-of c, however small dc may be
made; assume that the ring caused by the revolution of the area dhe bc, about
the axis af, be occupied by water, if sand be now fed into the machine with plenty
of water to give it freedom, the ring dhe bc will be taken up by the sand, with
sufficient water to fill the interstices, any grain of this sand as at h will be in a
static state, in other words will have no tendency, to move up or down the
curve dhe, the direction of the curve at being at right angles to the resultant of
the forces acting on the particle h, now any addition of sand, will have a tendency
to pass over the static wedge of sand dhe bc, which already occupies the space,
and will at best only touch the mercurial surface near d, in other words, will have
but a very limited opportunity of giving up its gold,-worse still-if now the feed
material be paid steadily into the machine, it is obvious, that any particles of sand
coming in with this constant feed, can only receive its energy of motion from the
inner periphery of the containing vessel, by transmission of force through the body
of mercury and the wedge of sand, and consequently each successive layer, as you
move from the containing vessel inwards towards the centre of the machine,
receives its energy from the next outer layer, and as a consequence, makes a less
number of revolutions per time, than any layer which is nearer to the containing
vessel; so that the surface of the feed sand, as it passes up the surface of the
mercury, would tend towards forming a paraboloid of revolution such as i j, much
shallower than the paraboloid shown in section as d he.
There are also other minor causes, which tend towards thickening the layer of
sand, at the lower part of the machine, which all tend towards making the feed
sand, pass up over a thick compact layer of sand, instead of over the surface of
mercury. Further if the feed material contains particles (such as pyrites), of a
higher than average specific gravity, they work their way in, and completely
occupy the static wedge d heb c.
Further still, the centrifugal force of the mass of sand, accumulated near the
bottom of the machine, presses against the lower part of the mercurial paraboloid
and tends to make it overflow at d and thus accentuates all the defects of the
"bottom feed."
After long continued and repeated alterative attempts to overcome these defects,
of the bottom feed, I discovered "the top feed" and "bottom outlet" as a method
of overcoming all these defects.
On referring to the diagram which shows a suppositional "bottom-outlet," it
will be seen how completely the whole body of accumulated sand, is tapped by the
"bottom outlet."
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :
1st. In ore separators, amalgamators and concentrators.
The centrifugal descension treatment of gold (and heavy metal) bearing
material; substantially as, and for the purposes set forth.
2nd. In ore separators, amalgamators and concentrators.
A centrifugal machine constructed in such a manner, that the material to be
treated enters and flows downwards over a mercurial surface, the mercury being
held by centrifugal force in position, in an outer drum as "A," the lighter portion
of the material escaping at the bottom of the outer drum "A"; substantially as
and for the purposes set forth.

page_text: 3rd. In ore separators, amalgamators, and concentrators.
"
"The top feed and "bottom outlet' method of treating heavy metal bearing
material; substantially as explained, and for the purposes set forth.
4th. In ore separators, amalgamators and concentrators.
The combination with an outer revolving drum as "A" of an inner revolving
dome as "C," said drum and dome being set with an annular space between them,
and provided with outlet vents or passages at the bottom of such space, substantially
as and for the purposes set forth.
5th. In ore separators, amalgamators and concentrators.
The combination with a drum as "A," of au annular groove as "U" formed
therein, substantially as and for the purposes described, and in the manner illustrated
on the accompanying drawings.
6th. In ore separators, amalgamators and concentrators.
The top distributing dome as "C," its locking cap as "D," the cover as "E,"
and their combination to form an air pump or fan, substantially as and for the
purposes set forth.
7th. In ore separators amalgamators and concentrators.
A hopper or inlet duct as "G," provided with a sieve or screen "J," with a
conically raised unperforated centre as described.
8th. In ore separators, amalgamators and concentrators.
The combination of the annular channel as "O" with a movable annular
director plate as "P," substantially as explained, and in the manner illustrated.
9th. In ore separators, amalgamators and concentrators.
The combination of an annular director plate as "P," with an annular channel
or race as "Q," substantially as and for the purposes set forth, and in the manner
illustrated.
10th. In ore separators, amalgamators and concentrators.
The combination of annular divisions with the channel "Q," substantially as and
for the purposes set forth.
11th. In ore separators, amalgamators and concentrators.
The general construction, arrangement, and combination of the whole of the
parts described and as shown on the drawings, to form a combined ore separator,
amalgamator and concentrator.
Signed this the Fourteenth day of August 1893
HENRI E
V
KITTON.