Improvements in Apparatus for Extracting Gold by Means of Mercury.
Year: 1895

page_text: Date of Application, 15th Aug., 1895
Complete Specification Left, 7th May, 1896-Accepted, 15th Sept., 1896
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Extracting Gold by Means of
Mercury.
I, JAMES WILLIAM BUTLER, of Blyth House, Humber Road, Blackheath, in
the County of Kent, Civil Engineer, do hereby declare the nature of this invention
to be as follows:-
My invention relates to apparatus for extracting gold by means of mercury
wherein the surface of the mercury is treated with hydrogen gas for the purpose
of preventing the mercury from sickening, oxidising or flouring. According to my
invention I construct such apparatus as follows.
A circular trough containing the requisite layer of mercury has a central shaft
carrying an annular gas holder of nearly the same size as the interior of the
mercury trough the bottom surface of which gas holder rests on the surface of the
mercury. This gas holder is supplied with hydrogen gas, either prepared
externally, or by preference generated within the same, for which purpose it con-
tains glass or earthenware vessels charged with zinc and dilute sulphuric acid.
Within the gas holder are arranged a number of inclined perforated pipes, the
lower open ends of which pass through the bottom of the gas holder so as to
deliver the hydrogen gas from the latter on to the surface of the mercury, the
pipes being made to incline towards the outer circumference of the gas holder, so
that on the rotation of the latter the gas will be ejected or drawn from the pipes
on to the mercury by centrifugal action.
There are provided a number of the said pipes so placed that their openings
pass over concentric circular paths of different diameters, so that collectively they
pass over the entire surface of the mercury with the exception of the central part
thereof.
In the central space surrounded by the annular gas holder a feed hopper for the
pulverised ore to be treated is attached to the central shaft, which hopper has a
number of openings round its periphery through which the ore mixed with water
issues on to a curved shield which guides it down to the inner periphery of the gas
holder. Here it is caused by centrifugal action to pass in a thin layer underneath
the gas holder, in close contact with the mercury, which takes up the gold there-
from as it travels towards the outer circumference of the mercury trough, over the
edge of which the spent slime escapes.
Thus by my above described invention, as the ground ore and water, or slime
is passed by centrifugal action between the mercury and the underside of the gas
holder, hydrogen gas is at the same time delivered from the latter on to the mercury
so as to keep it from oxidising.
Instead of generating the hydrogen gas within the gas holder as described, it
may be generated in separate apparatus, and conveyed into the gas holder through
a pipe having a revolving packed joint in the axial line thereof."
In order to keep the slime from settling in the trough, the periphery of the
gas holder may be made with serrations in such manner that the slime is forced
thereby against similar serrations on the wall of the trough.
The discharge of hydrogen from the gas holder on to the mercury can be
regulated or more or less cut off by providing the before mentioned perforated

page_text: pipes with valves or slides that are actuated by rods passing through stuffing boxes
in the sides of the gas holder.
The before mentioned vessels containing the materials for producing the hydrogen
within the gas holder, may be conveniently be introduced into the latter through
openings at top that are closed gas tight by suitable covers.
In the bottom of the mercury trough are provided discharge pipes with cocks
for discharging the mercury when it has become sufficiently amalgamated with
gold.
2 1005
ABEL & IMRAY,
Agents for the Applicant.
Improvements in Apparatus for Extracting Gold by Means of
Mercury.
I, JAMES WILLIAM BUTLER of Blyth House, Humber Road, Blackheath, in
the County of Kent, 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:-
My invention relates to apparatus for extracting gold by means of mercury
wherein the surface of the mercury is treated with hydrogen gas for the purpose
of preventing the mercury from sickening, oxidising or flouring. According to my
invention I construct such apparatus as follows:-
A circular trough containing the requisite layer of mercury has a central shaft
carrying an annular gas holder of nearly the sanie size as the interior of the
mercury trough the bottom surface of which gas holder rests on the surface of
the mercury. This gas holder is supplied with hydrogen gas, either prepared
externally, or by preference generated within the same, for which purpose it
contains glass or earthenware vessels charged with zinc and dilute sulphuric acid.
Within the gas holder are arranged a number of inclined perforated pipes, the
lower open ends of which pass through the bottom of the gas holder so as to
deliver the hydrogen gas from the latter on to the surface of the mercury, the
pipes being made to incline towards the outer circumference of the gas holder, so
that on the rotation of the latter the gas will be ejected or drawn from the pipes
on to the mercury by centrifugal action.
There are provided a number of the said pipes so placed that their openings
pass over concentric circular paths of different diameters, so that collectively they
pass over the entire surface of the mercury with the exception of the central part
thereof.
In the central space surrounded by the annular gas holder a feed hopper for
the pulverized ore to be treated is attached to the central shaft, which hopper has
a number of openings round its periphery through which the ore mixed with water
issues on to a curved shield which guides it down to the inner periphery of the
gas holder. Here it is caused by centrifugal action to pass in a thin layer under-
neath the gas holder, in close contact with the mercury, which takes up the gold
therefrom as it travels towards the outer circumference of the mercury trough,
over the edge of which the spent slime escapes.
Thus by my above described invention, as the ground ore and water, or slime
is passed by centrifugal action between the mercury and the underside of the gas
holder, hydrogen gas is at the same time delivered from the latter on to the
mercury so as to keep it from oxidising.
Instead of generating the hydrogen gas within the gas holder as described, it

page_text: may be generated in separate apparatus, and conveyed into the gas holder through
a pipe having a revolving packed joint in the axial line thereof.
In order to keep the slime from settling in the trough, the periphery of the gas
holder may be made with serrations in such manner that the slime is forced thereby
against similar serrations on the wall of the trough.
The discharge of hydrogen from the gas holder on to the mercury can be
regulated, or more or less cut off by partially or entirely withdrawing the zino
from the acid or by providing the before mentioned perforated pipes with valves
or slides that are actuated by rods passing through stuffing boxes in the sides of
the gas holder.
The before mentioned vessels containing the materials for producing the hydrogen
within the gas holder, may be conveniently introduced into the latter through
openings at top that are closed gas tight by suitable covers.
In the bottom of the mercury trough are provided discharge pipes with cocks
for discharging the mercury when it has become sufficiently amalgamated with gold.
Figure 1 of the accompanying drawings shews a cross-section of the arrangement
of the above described improved apparatus which I prefer to employ ;
Figure 2 shews a part plan and part horizontal section.
A is a circular trough containing a charge of mercury B, which can be
discharged therefrom by pipes C with stop cocks.
In contact with the surface of the mercury is an annular gas holder D carried
by a shaft E supported at top and bottom in suitable bearings.
Through openings in the top of the gas holder are introduced any required
number of vessels F, charged with dilute acid and zinc in the well known manner
for producing hydrogen gas, which passes through openings f into the gas
holder D.
The vessels are fitted gas tight into the gas holder, either by a liquid or sand
lute as shewn or by other means.
In the bottom surface of the gas holder are formed a number of holes in which
are fixed the lower ends of perforated tubes G, through which consequently the
hydrogen gas produced issues on to the surface of the mercury.
The tubes G are arranged so as to incline outwards at their lower ends as
shewn so that by the centrifugal action thus produced on the rotation of the gas
holder the hydrogen is drawn or forced out of the latter on to the mercury with
increased force.
The said openings and their tubes are arranged in any suitable manner, such as
that shewn so that collectively they cover, in rotating, the entire annular surface
of the gas holder in contact with the mercury. For regulating and stopping the
supply of hydrogen when required, the zinc body H in the vessels is suspended
from a rack I that can be raised and lowered by a pinion and hand wheel J so as
to be raised more or less out of the acid. Or the zinc body may be attached to a
screwed vertical rod passing through a screwed hole and provided with a nut for
screwing it up and down.
The ore to be treated mixed with water is fed from a shoot K into a hopper L
carried by and revolving with the shaft E, whence it is distributed through holes
on to the curved shield M which guides it to the inner rounded edge of the gas-
holder D so as to be drawn by centrifugal action between the gas holder and the
mercury, the exhausted ore being discharged at the outer circumference of the gas
holder, over a spout A', below which is placed a vessel to retain any gold that may
escape. The shaft E is driven by a pulley N or other suitable gearing from a
motor engine or mill shaft. The gas holder D is provided with eyes Ọ by which
it can be suspended from a crane, when required to be removed from the mercury
trough.
When the hydrogen gas is supplied to the gas holder D from an extraneous
source, the upper end of the shaft E may be made tubular, as shewn at Figure 3,
and connected on the one hand by pipes P to the gas holder, and on the other hand
by a stuffing box Q to the supply pipe R.

page_text: 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 :-
1. Apparatus for extracting gold by means of mercury wherein an annular
chamber or gas holder charged with hydrogen gas is caused to revolve upon the
surface of mercury contained in a trough, the hydrogen gas being discharged
through openings in the bottom of the gas holder on to the surface of the mercury
while the ore to be treated supplied through the central space of the gas holder
is made to pass between the gas holder and the mercury, substantially as
.described.
2. In apparatus for extracting gold by means of mercury, such as is referred to
in the first claim, the combination with the revolving gas holder of appliances
for generating hydrogen gas within the same, substantially as described.
3. In apparatus for extracting gold by means of mercury such as is referred to
in the first claim, providing the discharge openings in the bottom of the gas holder
with outward inclined discharge tubes for the purpose of accelerating the discharge
of the hydrogen gas by the centrifugal action, produced by the inclination of the
said tubes, substantially as described.
4. In apparatus for extracting gold by means of mercury the combination with
a circular trough A containing mercury of a revolving annular gas holder D
carried by a central shaft E, vessels F for generating hydrogen gas within the gas
holder, and openings provided with inclined tubes for discharging the hydrogen
gas on to the mercury arranged and operating substantially as described with
reference to the drawings.
Dated this 7th dor of Mer 1806
ABEL & IMRAY,
Agents for the Applicant.