Improvements in Milling all kinds of Ores Containing Gold or Silver, and Apparatus for this Purpose.
Year: 1895

page_text: Date of Application, 7th Mar., 1895-Accepted, 20th July, 1895
COMPLETE SPECIFICATION.
Improvements in Milling all kinds of Ores Containing Gold or Silver,
and Apparatus for this Purpose.
We, JOHN GLENVILLE MURPHY, Mining Engineer, and RICHARD WILLIAM
FRANK ABBÉ, Manufacturer, both of No. 60 New Street, in the City, County and
State of New York, 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 our invention is to provide a new or improved process of milling
all kinds of ores containing gold or silver in an effective and economical manner
and also to provide a new and improved apparatus for carrying out our process in
the most effective and expeditious manner.
In the accompanying drawing a vertical longitudinal sectional view of our
improved apparatus for treating ores containing gold or silver is shown.
The cylinder A is provided with the two end heads B and B each provided with
an exterior central bearing neck C and C¹ which necks are mounted to rotate in the
bearings D and D' secured on suitable supports.
Adjacent to the outer end of each supporting neck C and C¹ a fixed piece E
and E' is arranged which is provided with a circular groove for receiving a circular
spline or feather projecting from the outer end of the corresponding neck.
Each fixed piece E and E' is provided with an outwardly projecting neck F
and F respectively at the bottom part and in said necks the shafts G and G'
respectively are mounted to rotate which shafts support the conveyor screws H
and H which project a greater or less distance into the necks C and C¹.
b
The shafts and F¹ are provided at their outer ends with the belt pulleys over
which the driving belts pass for rotating said shafts and the screws thereon.
The neck C is the inlet neck and its fixed piece E is provided with an aperture I
in its upper part through which aperture the nozzle J projects into the cylinder
which nozzle has its inner end bevelled or cut off diagonally so that the current of
air passing through the same does not pass in a straight line through the cylinder
and directly out through the outlet neck Cl but on the contrary is thrown toward
the periphery of the cylinder so as to be thoroughly commingled with the dust or
finely pulverized ore in the cylinder.
The outer end of the nozzle J is connected with a compressed air supply pipe H
which is connected with a suitable air compressing device of any approved con-
struction not shown which compressed air supply pipe is provided with the damper
valve L and with the sliding gate M for closing more or less the relief opening N
in the compressed air supply pipe K and by means of said damper valve L and
gate M the quantity of compressed air passing into the cylinder can easily be
regulated.
The fixed piece E is provided in its bottom part with a horizontal neck O
extending outward and through which the conveyor screw H passes and said neck
is connected at its outer end with a feed pipe P through which the crushed ore is
conducted to the neck O.
The piece E' adjacent to the outlet neck C' is shaped to form the upwardly
curved duct Q with the lower end of which the discharge tube R is connected.
Said discharge tube R which may be of greater or less height as the nature of
the ore under treatment may require is provided at its upper end with a hood S
having a top outlet opening S¹ of less diameter than that of the discharge tube so
that the current of air is checked for a purpose that will appear hereinafter.

page_text: The cogwheels d and e serve for rotating the cylinder. The cylinder is provided
with a porcelain lining T and contains a greater or less quantity of porcelain balls
or flint pebbles V.
The crushed ore passing through the supply or feed pipe P drops into the neck O
and is conveyed by the screw H into the inlet neck C and into the cylinder where it
is pulverized by the porcelain balls or pebbles. The compressed air entering
through the nozzle J carries the particles of precious metal and gangue out through
the outlet neck and upward in the discharge tube R.
The lightest particles which have the desired degree of fineness are carried by
the current of air through the discharge tube and its hood and pass into a suitable
closed bin or receptacle and the coarser particles which strike against the top of
the hood S or are too heavy for the current of air to carry them to the top of the.
discharge tube drop down into the curved duct Q and are conveyed by the
screw H¹ back into the outlet neck C' and to the cylinder where they are re-ground
until they have the desired degree of fineness and can be carried by the current of
air into the above mentioned. bin.
The crushed ore is thus fed continuously and automatically into the cylinder and
the ore that has been pulverized to the desired degree of fineness is carried off
automatically so that the cylinder requires no attention whatever.
The pressure of the current of compressed air must be regulated according to
the nature of the ore under treatment as the gangue of some ores is heavier than
that of others.
The pulverized ore that accumulates in the bin is in the form of impalpable
powder and is of sufficient fineness to pass through a screen having from 200
to 250 meshes to the lineal inch.
This impalpable powder is blown from the bin into an amalgamating pan having
amalgamated copper plates and at the same time water is admitted into said pan to
form a paste.
The gold or silver contained in the impalpable powder adheres to the amalgamated
copper plates and the paste is washed into a settler in the usual manner.
The ore having been reduced to an impalpable powder cannot flour or in any
other way injuriously affect the mercury as the extremely fine condition into which
it has been reduced prevents the same from affecting the mercury by impact.

page_text: 2. The process of milling ores containing gold and silver consisting in pulverizing
the ore to an impalpable powder blowing this powder into an amalgamating pan
and adding water to form a paste whereby the gold and silver adheres to the
amalgamated plates in the pan substantially as herein shown and described.
3. The process of dry concentrating gold ores consisting in converting the ore
into an impalpable powder and blowing the powder produced from the pulverizer
into a vertical shoot and thus separating the lighter gangue from the heavier gold
by gravity substantially as herein shown and described.
4. The combination with a cylinder of an inlet neck on one head of the cylinder
an outlet neck on the other head of the cylinder and a conveyor screw mounted at
each of said necks to convey the material under treatment into the cylinder and
means for operating said screws substantially as set forth.
5. The combination with a cylinder of an inlet neck on one head of the cylinder
an outlet neck on the other head a conveyor or screw located at each neck for
conveying the material under treatment into the cylinder a pipe for supplying
material to be pulverized to the cylinder a compressed air supply tube for conducting
compressed air into the cylinder and an outlet tube connected with the outlet neck
of the cylinder substantially as herein shown and described.
6. The combination with a cylinder of an inlet neck on one head of the same an
outlet neck on the opposite head a conveyor screw located at each neck for
conveying the material under treatment into the cylinder a pipe for supplying
material to be pulverized a compressed air supply tube for conducting air under
pressure into the cylinder and a vertical outlet tube connected with the outlet neck
of the cylinder which outlet tube is provided at its upper end with an enlargement
substantially as herein shown and described.
7. The combination with a cylinder of an inlet neck on one head of the same an
outlet neck on the opposite head a conveyor screw located at each neck for
conveying the material under treatment into the cylinder a pipe for supplying
material to be pulverized a compressed air supply pipe for conducting air under
pressure into the cylinder and a vertical outlet tube connected with the outlet neck
of the cylinder and provided at its upper end with an enlargement the top of
which is reduced to less than the diameter of the outlet tube substantially as herein
shown and described and as shown in the drawings.
8. The combination with a cylinder of an inlet neck on one head of the same
and an outlet neck on the other head of a fixed piece adjacent to cach neck a
material supply or feed pipe and a compressed air supply pipe connected with one of
said fixed pieces a nozzle held in said piece and projecting into the cylinder and
having its end bevelled or cut off diagonally and an outlet tube connected with the
other fixed piece substantially as herein shown and described.
Dated this 7th day of March 1895.
TONGUE & BIRKBECK,
Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicants.