Improved Amalgamating Apparatus for Extraction of Precious Metals from Minerals.
Year: 1898

page_text: Date of Application, 8th Dec., 1896
Complete Innrifination Inst 1ot Cont 1000
1000
Complete Specification Loft, 1st Sept., 1900 Accepted, 21st Oct.,
1000
1600
PROVIDIUNAL DIUINICATION.
...
Improved Amalgamating Apparatus for Extraction of Precious
Metals from Minerals.
I, ANTOINE LAVOIX, of 7, Rue Chateaudun, Paris, in the Republic of France,
Engineer do hereby declare the nature of this invention to be as follows:-
The different methods of amalgamation now employed for the extraction of
gold and silver leave a rather large proportion of precious metal in the minerals
after the operation, this being in consequence of the difficulty that there is in
bringing all the particles of the minerals into sufficiently long and intimate
contact with the quicksilver.
My invention relates to an amalgamating apparatus for large delivery allow-
ing of extracting all the gold or silver from the minerals and consists essen-
tially in passing the minerals in suspension in water from below to the top
through a ring like layer of quicksilver, not thick but comprised between two
cylinders, whilst the mass is fast stirred up by rotation of one of the cylinders
provided with pins covering its whole circumference in contact with the quick-
silver and while on the other hand the raising of the minerals is delayed by
circular ribs carried by the cylinders and arranged in convenient spaces one from
the other in order to thow back the minerals upon the pins of the rotating
cylinder to secure intimate and prolonged .contact of all the particles with the
quicksilver.
My apparatus comprises essentially two vertical concentric cylinders with
an annular space between them which is filled with quicksilver during action
and which forms the amalgamation field.
The outer cylinder may be composed of parts or sectors riveted or bolted
together along the whole height and it rests upon the ground on regulating
screws allowing in conjunction with water levels of the true vertical adjustment
of the apparatus.
Each bracket forming a nut for the regulating screw and also each water level
box may be of iron cast with one of the sectors of the cylinder so that the several
parts of this cylinder are identical and require only one pattern and mould.
The cylinder is closed below by a riveted bottom of cast iron with a ribbed
frame which forms a centre pedestal for supporting the shaft of the inner cylinder
and also carries the pipe for the inflow of the mixture of water and mineral and
the pipe for outflow of the residue. This latter pipe serves also during the
working of the apparatus for periodically evacuating the amalgam.
On its top end the cylinder has also a rivetted head perforated with windows
or holes and carrying the different organs for operating the rotation of the inner
cylinder.
The inner cylinder is open at its lower end and its inner border is at little
distance from the bottom of the outer cylinder; this cylinder has a plane bottom
at a convenient height from its lower end and rests upon the under frame by
means of a shaft. Upon the boss at the centre of the head of the inner cylinder

page_text: is keyed a bevelled wheel destined to revolve the cylinder. This wheel gears with
a bevelled pinion keyed on a horizontal shaft supported and guided by a long
bearing made of cast iron in the head of the outside cylinder. On the outside of
the apparatus this shaft carries a fast driving pulley and a loose pulley. When
the apparatus is working the thrust resulting from the flowing in under pressure
of the liquid in the inner cylinder tries to lift this cylinder so that it must be
provided on its top end with a very good bearing conveniently oiled. For this
purpose is keyed on the head a shaft whose top end: forms a socket and turns
upon a stationary pivot formed by a screw held in the head of the outer cylinder.
This screw carries keyed on it a worm wheel which gears with an endless screw
turning in supports carried by the head and which is put into action by means
of a hand wheel when the pivot is to be screwed down for compensating for wear.
The oiling of the socket is secured by an oiler from which passes a pipe
arranged in the axle of the pivot.
The inner cylinder carries upon its whole outer circumference metallic pins
screwed into its thickness or fastened in any other convenient manner to pro-
ject slightly less than the width of the annular space between the two cylinders.
This cylinder has also on its outside and from distance to distance circular ribs
making small flanges and the outer cylinder has on its inner circumference
circular ribs situated each about in the middle of the intermediate space between
each two ribs of the inner cylinder and forming a larger flange than the latter
ribs and very little inferior to the width of the annular space. In practice
for allowing the easy replacement of the pins after wear, these pins instead of
being fastened in the wall of the cylinder can be fastened in metallic rings or
jackets fitting on the cylinder and arranged each between two succeeding ribs.
Each ring itself must be of segments united by lugs and bolts, which allow
quick assemblage and dismounting. In this case the pins can be even of cast
iron with the ring segments covering the cylinder. The amalgamator works
as follows: The apparatus being first put in exactly vertical position and the
blow off cock being closed, one introduces quicksilver till its level arrives at the
height of a valve arranged on the inlet pipe. This quantity of quicksilver is
estimated as sufficient for filling the whole annular space between the two
cylinders when it is confined to that space.
The inlet pipe being put in communication with a pump delivering the mixture
of water and mineral with a pressure of 4 to 5 kilograms or thereabouts per
square centimeter the tap of the inlet pipe is opened, the liquid laden with
minerals lifts the valve and falls back over the surface of the sheet of quicksilver
the level of the water rises and the air is compressed under the full bottom of
the inner cylinder, forming a bell whilst the level of the quicksilver goes down
in the inner cylinder and rises in the annular space between the two cylinders.
As soon as the quicksilver is gone down in the cylinder to a line below its
lower edge the water and the minerals pass the border of the cylinder and
traverse from below to the top the layer of quicksilver with a rapidity partly
depending upon the height of the quicksilver column. It will be understood that
it is useful for the border of the inner cylinder to be entirely horizontal in order
that the water and minerals escape along the whole circumference of this cylinder
and that the whole annular mass of quicksilver works at the same time.
The driving pulley of the inner cylinder being then engaged this cylinder
begins to turn. In accordance as the water and the minerals rise in traversing
the quicksilver a strong agitation is produced in the liquid along its whole
height by the pins so that the different particles of the minerals come into
intimate contact with the quicksilver and all the precious metal is dissolved.
The rising movement of the minerals is diminished or delayed moreover by
the circular ribs of the cylinders disposed so as to form a zigzag course; the
projection of the ribs of the outer cylinder being moreover larger than that of
the ribs of the inner cylinder the minerals are always thrown back towards the
inner cylinder to undergo the action of the pins on the spot where it is most felt

page_text: and which considerably increases the efficacy of the process, that is the detaching
or breaking up of the different particles or the detaching of the already formed
amalgam from the surface of these particles.
I may remark that the inner cylinder is also provided towards its lower end
on its inner surface with a certain number of pallets which rotating in the
midst of the water laden with minerals stir up the sediments therein so that the
process of amalgamation may act regularly.
The outside cylinder has near its top end a gauge level pipe showing at what
moment quicksilver must be supplied to the apparatus.
The mixture of water and residues arriving at the upper part of the apparatus
after the amalgamation, passes out through a pipe.
My amalgamating apparatus thus made is essentially industrial, will give a
considerable delivery, and extract the whole of the precious metals contained in
the minerals.
Dated thin 8th day of Danambar 1000
Improved Amalgamating Apparatus for Extraction of Precious
Metals from Minerals.
I, ANTOINE LAVOIX, of 7, Rue de Chateaudun, Paris, in the Republic of France,
Civil Engineer, 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 different methods of amalgamation now employed for the extraction of
gold and silver leave a rather large proportion of precious metal in the minerals
after the operation, this being in consequence of the difficulty that there is in
bringing all the particles of the minerals into sufficiently long and intimate
contact with the quicksilver.
My invention relates to an amalgamating apparatus for large delivery allow-
ing of extracting all the gold or silver from the minerals, and consists essen-
tially in passing the minerals in suspension in water from below the top
through a ring like layer of quicksilver of considerable height comprised between
two cylinders, whilst the mass is energetically stirred by the rotation of one of the
cylinders provided with pins or teeth projecting outward on its whole surface
in contact with the quicksilver, and while on the other hand the raising of the
minerals is delayed by other broad teeth arranged in rings placed one above the
other secured to the stationary cylinder and entering between the teeth of the
rotating cylinder, securing thus intimate and prolonged contact of all the particles
with the quicksilver.
The apparatus will give the same result if the rotating cylinder is alone
provided with pins or teeth in order to produce the stirring; in this case the
raising of the minerals is delayed by circular ribs provided on both cylinders
conveniently spaced, and alternating from one cylinder to the other so as to
form a zigzag course.
The accompanying drawing shows the amalgamating apparatus of my invention.
Fig. 1 is a vertical section of the apparatus.
Fig. 2 is a horizontal section on the line 1-2 of Fig. 1.
Fig. 3 is a sectional partial elevation of the apparatus in the construction of
which the interior rotating cylinder is alone provided with pins which are screwed

page_text: in its walls, while the two cylinders are made with circular ribs conveniently
spaced one from the other and arranged so as to form a zigzag course from one
cylinder to the other.
Fig. 4 is a modified construction of the lower part or bottom of the apparatus.
My apparatus comprises essentially two vertical concentric cylinders A and B
with an annular space between them which is filled with quicksilver during action
and which forms the amalgamation field.
The two cylinders are composed of portions united together by means of
strong flanges and bolts, and the exterior cylinder which carries the other one,
as will be hereinafter described, rests upon a large hollowed base, of cast iron S
by means of three regulating screws or threaded rods a allowing in conjunction
with three water-levels 6 the true vertical adjustment of the apparatus. Each
screw is set upon the base S by the collar a¹, the pin p and the lower nut q.
The screws or threaded rods pass loosely through brackets A¹ of the cylinder A
and nuts placed on the threaded parts of the rods below the brackets A¹ allow
the lifting and lowering of the cylinders. The jam-nut i' and the upper nuts jj¹
allow of the maintenance of the apparatus in a steady position.
The cylinder A is closed below by a riveted bottom Cof cast iron with a ribbed
frame D which forms a centre pedestal for supporting the shaft o of the cylinder B
and also carries the pipe e for the inflow of the mixture of water and mineral
and the pipe f for the outflow of the residue. This latter pipe serves also during
the working of the apparatus for periodically evacuating the amalgam.
On its top end the cylinder has also a rivetted head F perforated with windows
or holes and carrying the different organs for operating the rotation of the
inner cylinder B.
The inner cylinder B is open at its lower end and its inner border is a little
distance from the bottom C of the outer cylinder; the cylinder has a flat bottom h
at a convenient height from its lower end and rests upon the frame 1 by means
of its shaft o solidly fastened in the boss h¹ cast in one with the bottom / and
strengthened by ribs u.
At the upper part, the cylinder B is made with a riveted head G provided with
a central boss upon which is keyed a bevelled wheel & destined to revolve the
cylinder; this wheel gears with a bevelled pinion keyed on the horizontal
shaft supported and guided by a long bearing F made of cast iron in the
head F of the outside cylinder; on the outside of the apparatus the shaft
carries a fixed driving pulley m and a loose pulley m¹.
When the apparatus is working the thrust resulting from the flowing in under
pressure of the liquid in the cylinder B tries to lift this cylinder so that it must
be provided on its top end with a very good bearing B conveniently oiled. For
this purpose the bearing B' is bolted on the central boss of the head G and it
turns upon a stationary pivot formed by a screw n held in the head F of the
outer cylinder which forms a nut; this screw carries keyed on it a small hand
wheel V which allows to compensate for wear when it is necessary by lowering
the pivot, and a hand nut E placed on the screw above the head F forms a block-
ing jam-nut for keeping the screw in a fixed position.
The oiling of the socket is secured by an oiler r from which passes a pipe rl
arranged in the axle of the pivot.
On the inner cylinder and loosely passed over it, are provided rings of small
height secured to the cylinder by means of vertical keys z¹. Each ring z is
made of iron cast with a series of teeth s projecting on its outer surface, so that
by the union of the different rings z, the exterior surface of the rotating cylinder B
is provided with teeth or pins through its whole height which are arranged in
horizontal rows.
Besides, rings y of iron cast with inner teeth s¹ are arranged and introduced
one above the other in the cylinder A and are secured to this cylinder by a key.
The horizontal rows of teeth s¹ alternate with the rows of teeth.
In Fig. 3 I have represented a slightly modified construction of the cylinders.

page_text: The teeth & instead of being cast with the rings secured to the rotating cylinder B
are screwed into the walls of said cylinder; instead of having a flat or rectangular
section they may be cylindrical in this construction.
The teeth of the stationary cylinder are dispensed with and in order that the
rising movement of the minerals be properly delayed, the cylinder B is provided
on its outside from distance to distance, with annular ribs t, and the cylinder A'
is provided on its inside with annular ribs t¹ arranged about in the middle of the
space between two ribs t; the mineral is thus forced in its rising movement to
follow a zigzag course.
In Fig. 4 I have represented a modified construction of the lower part of the
apparatus, whereby the pipe e is provided on its vertical portion with ports e¹ to
facilitate the inflow of the mixture of water and mineral.
The amalgamator works as follows:-
The apparatus being first put in exactly vertical position and the blow off
cock being closed, quicksilver is introduced until its level approaches tho
outlet opening of the pipe e. This quantity of quicksilver is estimated as
sufficient for filling the whole annular space between the two cylinders when
it is confined to that space.
The pipe e being put in communication with the one of an elevated reservoir
or with a pump delivering the mixture of water and mineral with a pressure of 4
to 5 kilograms or thereabouts per square centimeter. the liquid laden with
mineral enters the apparatus over the surface of the sheet of quicksilver: the
level of the water rises and the air is compressed under the full bottom h form-
ing a bell, whilst the level of the quicksilver goes down in the cylinder B and
rises in the annular space between the two cylinders.
As soon as the quicksilver is gone down in the cylinder B to the line X-Y.
the water and the minerals pass the border of the cylinder B and traverse, from
below to top. the layer of quicksilver with a rapidity partly depending upon
the height of the quicksilver column. It will be understood that it is useful
for the border of the inner cylinder B to be entirely horizontal in order that the
water and minerals escape along the whole circumference of this cylinder and
that the whole annular mass of quicksilver works at the same time.
The driving pulley m of the cylinder B being then engaged, this cylinder
begins to turn. In accordance as the water and the minerals rise in traversing
the quicksilver a strong agitation is produced in the liquid along its whole
height by the teeth s so that the different particles of the minerals come into
intimate contact with the quicksilver and all the precious metal is dissolved.
The teeth of the rotating cylinder being alternatively opposite the stationary
teeth or the intervals between said teeth, the rising currents of water and
minerals which are liable of formation in the different intervals above each
other, are constantly broken and deviated sideways delaying thus the rising
movement of the minerals and facilitating their amalgamation.
In the case of Fig. 3, the teeth or pins s assure the energetic stirring of the
mass of mineral and quicksilver; as to the rising movement of the minerals, it is
delayed by the circular ribs t and t¹ of the cylinders arranged so as to form
a zigzag way.
I may remark that the cylinder B is also provided towards its lower end on
its inner surface with a certain number of pallets which, rotating in the midst
of water laden with minerals, stir up the sediments in this mass so that the
process of amalgamation may act regularly.
The outer cylinder A has besides near its top end an enlarged portion which
forms an annular chamber H in which will gather the water and residues which
are then cleared away by the tube R. If it be desired to clean the apparatus, a
small tube R¹ at the bottom of the annular chamber allows the emptying of the
residues.
Finally two gauge level pipes T and T allow constantly the working of the
liquid and the changes of level of the quicksilver as it gets used to be ascertained.

page_text: My amalgamating apparatus thus made is essentially industrial, will, give.a
considerable delivery, and, extract nearly the whole of the precious metals
contained in the minerals.
I reserve the right, should the apparatus be. employed. in very cold countries,
to provide it with a vapour jacket to. prevent the freezing, of the liquids. For
this purpose, the portions of the cylinder A may be constructed with a double
wall, or the apparatus may be kept as, shown in the drawing and enclosed, entirely
in a steam-tight sheet-iron casing in which steam would pass.
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. An improved amalgamating apparatus for the extraction of precious metals
from minerals wherein the minerals in suspension in. a mass of water traverse
under pressure from. below to top an annular layer of quicksilver of slight thick-
ness and of considerable height comprised between two cylinders, whilst the mass
is stirred by the rotating of one of the cylinders provided with teeth or pins
throughout its circumference in contact with the quicksilver, the rising move-
ment of the minerals being delayed either by rings with teeth carried by the
stationary cylinder or by circular, ribs carried by the two cylinders so as to
secure the intimate and prolonged contact of all the particles of the mineral
with the quicksilver.
.
-
2. In an.
amalgamating apparatus as in Claim 1, the arrangement of a
cylinder A resting upon a base S by three regulating screws allowing of its
vertical adjustment in combination with an inner concentric cylinder 13 pro-
vided with teeth or-pins on its outer circumference, open at the under part with
a perfectly horizontal edge resting upon. the bottom of the first cylinder by means
of a central pivot and receiving a rotating movement by means of a driving gear
carried by the head, or arranged above the outer cylinder A, substantially as
herein before described and illustrated. in the accompanying drawing.
3. In an amalgamating apparatus as in Claim 1 the arrangement of a cylinder A
resting upon a base S by three regulating screws in combination with an inner
concentric cylinder B open at its under part and receiving whilst the apparatus
is. at work a continuous rotating movement,in combination with rings of one
piece z. of iron cast with a horizontal row of pins or teeth s and..arranged one
above the other and keyed with the cylinder B, and in combination with rings
of one piece of iron cast with a horizontal row of teeth s¹ and arranged one
above the other .in the interior of the stationary cylinder B to which they are
keyed, so that the horizontal rows of teeth s¹ alternate with the horizontal rows
of teeth substantially as hereinbefore described and illustrated in the accom-
panying drawing.
"
4. In an amalgamating apparatus as in Claim- 1, a cylinder A resting upon a
base S by three regulating screws and having on its inner surface circular ribs t
conveniently spaced one from the other, in combination with .an, inner cou-
centric cylinder B open at its under part, receiving a continuous, rotating move-
ment and provided on its outer surface with screwed pins s and circular ribs t
alternating with the ribs. of the stationary cylinder substantially as herein-
before described and illustrated in the accompanying drawing..
HERBERT HADDAN & Co., •
Agents to Applicant, 18, Buckingham Street, Strand, W.C.,. London.