Improvements in or relating to Apparatus Employed in the Recovery of Precious Metals from their Solutions.
Year: 1895

page_text: Date of Application, 7th Feb., 1890
Complete Specification Left, 7th Nov., 1895-Accepted, 7th Dec., 1895
PROVISIONAL SPECIFICATION.
Improvements in or relating to Apparatus Employed in the
Recovery of Precious Metals from their Solutions.
I, HENRY LIVINGSTONE SULMAN of 60 Gracechurch Street in the City of
London, Analytical Chemist, do hereby declare the nature of this invention to be
as follows:-
:―
This invention relates to apparatus which may be employed in recovering
precious metals, and particularly gold, from their solutions, and although the
apparatus could be employed with other precipitating agents, I have particularly
designed it for use where zinc is the precipitating agent, and for the present
I will so describe it. The zinc that I prefer to employ is in the state of a very fine
powder or fume, technically known as zinc dust, but the oxide of zinc it contains
somewhat delays or modifies its action upon the precious metal in solution and it
is therefore desirable to remove the coating of oxide on the minute particles
before applying the zine to the metallic solution; the first part of my apparatus
deals with this question.
I employ any suitable tank or vessel which may be provided with a hopper or
equivalent through which the zinc and liquor used in the process of removing the
oxide may be passed to the interior of the vessel, the bottom of which slopes to a
point from which extends a tube or pocket closed alternately at top or bottom by
a suitable valve arrangement, say two valves carried upon a wire or equivalent so
The
that when the bottom of the tube closed the top is opened and vice versa.
pocket or tube opens into a passage or channel which receives the gold solution
from another tank or vessel through a syphon, the vessel being supplied with
preferably a continuous stream of the gold solution, and having a ball float and
lever connected by any suitable mechanism with the previously described valve
mechanism of the first vessel, the arrangement being such that when the ball
float drops, the valve at the bottom of the pocket of the first vessel is opened and
that at the top closed, so that the charge of zinc powder contained in the pocket
is allowed to escape into the channel, the valve at the top of the pocket preventing
any more from entering. In operation, as soon as the second vessel is full of the
gold solution, with the ball float at the top and the bottom valve at the top of the
pocket, the syphon in the second vessel begins to operate, discharging the contents
of the second vessel into the channel already described. As the second vessel
empties, the ball float falls, altering the arrangement of the valves, lowering them,
and taking with them and discharging into the channel an amount of the zinc
equivalent to the capacity of the pocket. The charge from the pocket will be of
suitable proportions to deal with the charge of gold solution coming from the
second vessel, and is discharged into the channel meeting the solution, and carried
away with it.
From the previously described apparatus the solution and zinc pass by a
suitable pipe or channel to a cylindrical or preferably conical vessel around which
it swirls as it enters at one side and tangentially, thus effecting a very intimate
mixture of the solution and the zinc. This vessel also is provided with a syphon
which commences to act when the solution in it has risen to the proper level, the
syphon discharging the contents into an apparatus provided with a number of
inclined baffle plates down which the solution flows, thus effecting a further
admixture. It then rises between inclined plates placed in series close together of
any suitable material, say with advantage slate, upon which the gold and zinc

page_text: deposit and sliding down them fall to the bottom of the vessel while the liquor
escapes by the upper part of the vessel and flows away preferably through a filter
cloth or other filtering medium. The liquor escapes to a well or pump from
which it may be pumped for re-use in the process, while the gold or other precious
metal or zinc can be removed through mud-holes or by other suitable means.
Dated this 7th day of February 1895.
BOULT & WADE,
Agents for the Applicant.
Improvements in or relating to Apparatus Employed in the
Recovery of Precious Metals from their Solutions.
I, HENRY LIVINGSTONE SULMAN of 60 Gracechurch Street, in the City of
London, Analytical Chemist, do hereby declare the nature of this invention and in
what manner the same is to he performed, to be particularly described and
ascertained in and by the following statement:-
This invention relates to apparatus which may be employed in recovering
precious metals and particularly gold from their solutions, and although the
apparatus could be employed with other precipitating agents, I have particularly
designed it for use where zinc is the precipitating agent and for the present I will
so describe it.
In the accompanying drawing I have diagrammatically represented the apparatus
in which I employ any suitable tank or vessel A which may be provided with a
hopper or equivalent A¹ through which the zine B and liquor used in the process
of removing the oxide may be passed to the interior of the vessel A the bottom of
which slopes to a point from which extends a tube or pocket A' closed alternately
at top or bottom by a suitable valve arrangement, say two valves D¹ D³ carried
upon a wire or equivalent D so that when the bottom of the tube A2 is closed the
top is opened and vice versa. The pocket or tube A2 opens into a passage or
channel E which receives the gold solution F from another tank or vessel G through
a syphon H the vessel G being supplied with preferably a continuous stream of the
gold solution (as conventionally shewn by the cock 1) and having a ball float and
Jever J connected by any suitable mechanism as for example the chains and sector
lever K with the rod D of the valves D D² the arrangement being such that when
the ball float J drops say from the position shown in dotted lines to that indicated
in full lines in the drawing, the valves D¹ D² are lowered into the position shewn
in full lines so that the charge of zinc dust or fume between the two valves D' D
is allowed to escape into the channel, the valve D' then at the bottom of the pocket
preventing any more than this predetermined quantity from entering the
channel E. In operation, as soon as the vessel G is full of the gold solution F
with the ball float J at the top, and the bottom valve D' at the top of the
pocket A2 all as shown in dotted lines in the drawing, the syphon H in the vessel G
begins to operate, discharging the contents of the vessel into the channel E. As
the vessel G empties, the ball float J falls and allows the valves D' D2 to descend
and take with them and discharge into the channel E a quantity of the zinc B
equivalent to the capacity of the pocket A2 or dependent upon the distance
between the valves D D². The charge from the pocket A2 will be of suitable
proportions to deal with the charge of gold solution F coming from the vessel G
and is discharged into the channel E meeting the solution and carried away with it.
From the previously described apparatus the solution and zinc pass by a suitable
pipe or channel E¹ to a cylindrical or preferably conical vessel L around which it
swirls as indicated by the arrow, as it enters at one side and tangentially, thus
effecting a very intimate mixture of the solution and the zinc. This vessel L is

page_text: provided with a syphon H¹ which commences to act when the solution in it has
risen to the proper level, the syphon discharging the contents of the vessel L into
an apparatus or vessel M provided with a number of inclined baffle plates M¹ down
which the solution flows, thus effecting a further admixture. The solution then
rises between inclined plates N placed in series close together, of any suitable
material say with advantage slate, upon which the gold and zinc deposit and slide
down to the bottom of the vessel M while the liquor escapes by the upper part of
the vessel and flows over the plate O and preferably through a filter cloth or other
filtering medium P finally leaving by way of the outlet Q. The liquor then flows
into a well or sump from which it may be pumped for re-use in the process, while
the gold or other precious metal or zinc can be removed through mud-holes M² or
by other suitable means.
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. In apparatus employed in the recovery of precious metals from their solutions
the combination with a device for automatically discharging a predetermined
quantity of the solution of another device for automatically delivering into the
solution thus discharged a predetermined quantity of the precipitating agent.
2. In apparatus employed in the recovery of precious metals from their solutions
the combination with a vessel having a syphon such as H and valve operating float
device such as J K of another vessel provided with a pocket such as A² and two
valves D D all operating substantially as and for the purpose described and
illustrated in the accompanying drawing.
3. In apparatus employed in the recovery of precious metals from their solutions
the combination and arrangement of parts constituting the complete apparatus for
automatically discharging predetermined quantities of the solution and automatically
delivering into each quantity of solution thus discharged a predetermined quantity
of precipitating agent substantially as described and illustrated in the accompanying
drawing.
4. In apparatus employed in the recovery of precious metals from their solutions
a vessel having its inlet arranged tangentially so as to cause the solution admitted
to swirl around the vessel substantially as and for the purpose described and
illustrated in the accompanying drawing.
5. In apparatus employed in the recovery of precious metals from their solutions
the combination with a vessel having its inlet arranged tangentially of a syphon
such as H substantially as and for the purpose described and illustrated in the
accompanying drawing.
6. In apparatus employed in the recovery of precious metals from their solutions
a series of inclined plates or deposit surfaces such as N amongst which the solution
rises and deposits the metal substantially as described and illustrated in the
accompanying drawing.
7. In apparatus employed in the recovery of precious metals from their solutions
the combination and arrangement of parts constituting the complete apparatus for
allowing the metals to deposit and the liquor to separate therefrom and be
subsequently strained substantially as described and illustrated in the accompanying
drawing.
8. The combination and arrangement of parts constituting the complete apparatus
for employment in the recovery of precious metals from their solutions substantially
as described and illustrated in the accompanying drawing.
Dated this 1st day of November 1895.
H. LIVINGSTONE SULMAN.
Boult & Wade,
Agents for the Applicant.