Improved Means of Extracting Precious Metals from Ores.
Year: 1889

page_text: Date of Application, 16th Jan., 1889
Complete Specification Left, 15th Oct., 1889-Accepted, 16th Nov., 1889
PROVISIONAL SPECIFICATION.
Improved Means of Extracting Precious Metals from Ores.
I, JAMES BALLANTYNE HANNAY of Cove Castle, Loch Long in the County of
Dunbarton, Chemical Engineer, do hereby declare the nature of this invention to be
as follows:
My invention relates to means of extracting from ores precious metals, especially
gold, in the form of chloride solution. For this purpose, I employ apparatus which
consists of a chlorinating vessel, a set of circulating pumps, a filter press, and a
chlorine pump, or sets of these, with suitable communicating pipes, cocks and valves
for operating in the following manner. Having reduced the ore to a fine powder, [
mix it with water or with chlorinated water to a condition of thin sludge which can
be pumped. I charge the chlorinating vessel with this sludge and apply the pumps
to cause its circulation therein, drawing from the upper part and discharging into
the lower part, while chlorine gas is pumped into the vessel preferably to a pressure
considerably above that of the atmosphere. After circulation has gone on for some
time until the metal in the ore is mostly dissolved by the chlorine, the sludge is
caused to flow into the filter press, the necessary pressure being given if required by
using the chlorine pump to force air into the upper part of the chlorinating vessel.
The liquid issuing from the filter press, containing in solution the metallic chloride,
is treated in any of the known ways for soparating the metal and recovering the
chlorine. In some cases the solution discharged from the filter press may be used
in a subsequent operation to form the sludge by its admixture with a fresh quantity
of pulverised ore, and this may be done repeatedly so as to obtain finally a filtered
liquor rich in chloride.
As it is advantageous to charge the chlorinating vessel with an excess of chlorine
above that which enters into combination with the metals, I prefer to collect such
excess, before discharging the sludge, by blowing in a little steain to warn the sludge
and allowing the free chlorine thus liberated to pass either into a gasometer or into
another chlorinating vessel; or an exhaust pump may be employed to draw off the
free chlorine.
When metals, such as silver, are present, having insoluble chlorides, the blocks
which are taken from the filter press and which contain these chlorides are reduced
to sludge as before mentioned and are subjected to the same treatment with a
suitable solvent instead of the chlorine.
Dand thi 19th Tome 1000
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improved Means of Extracting Precious Metals from Ores.
I, JAMES BALLANTYNE HANNAY of Cove Castle, Loch Long, in the County of
Dunbarton, Chemical Engineer, do hereby declare the nature of this invention
and in what manner the same to be performed to be particularly described
and ascertained in and by the following statement :—
My invention relates to means of extracting from ores precious metals especially
gold in the form of chloride solution. For this purpose I employ apparatus which
consists of a chlorinating vessel, a set of circulating pumps, a filter press, and a
chlorine pump, or sets of these with suitable communicating pipes, cocks and valves
for operating in the following manner. Having reduced the ore to a fine powder

page_text: I mix it with water or with chlorinated water to a condition of thin sludge which can
be pumped. I charge the chlorinating vessel with this sludge and apply the pumps
to cause its circulation therein, drawing from the upper part and discharging into
the lower part, while chlorine gas is pumped into the vessel preferably to a pressure
considerably above that of the atmosphere. After circulation has gone on for some
time, until the metal in the ore is mostly dissolved by the chlorine the sludge is
pumped by the circulating pumps into the filter press, additional pressure being given
if required by using the chlorine pump to force air into the upper part of the
chlorinating vessel. The liquid issuing from the filter press containing in solution
the metallic chloride is treated in any of the known ways for separating the metal
and recovering the chlorine. In some cases the solution discharged from the filter
press may be used in a subsequent operation to form the sludge by its admixture
with a fresh quantity of pulverized ore, and this may be done repeatedly, so as to
obtain-finally-a-filtered liquor rich in chloride.
As it is advantageous to charge the chlorinating vessel with an excess of chlorine
above that which enters into combination with the metals, I prefer to collect such
excess before discharging the sludge by blowing in a little steam to warm the sludge
and allowing the free chlorine thus liberated to pass either into a gasometer or
into another chlorinating vessel; or an exhaust pump may be employed to draw off
the free chlorine.
When metals such as silver are present having insoluble chlorides, the blocks, which
are taken from the filter press and which contain these chlorides, are reduced to
sludge as before mentioned and are subjected to the same treatment with a suitable
solvent instead of the chlorine.
-
Although I by preference employ a filter press in combination with the chlorinating
apparatus, oliviously the chlorinated sludge might be filtered by other means..
Such being the general character of my invention I shall describe the apparatus
which I employ, referring to the accompanying drawing which is an elevation partly
in section of the chlorinating apparatus.
-A is the chlorinating vessel, which is charged through the manhole A' with
comminuted ore, this ore being mixed, either externally or in the vessel, with water
or partly with the liquid resulting from previous operations, into the condition of
thin sludge that can be pumped. The vessel A communicates by a pipe B from its
bottom and a pipe C from its top with the suction in the valve box d of a set of
circulating pumps D each of those pipes being furnished with a cock or valve b
and c respectively. The pipe B also communicates through a cock or valve b¹ with
the discharge of the pumps D) and also communicates by a pipe E, having cock or
valve e, with a filter press F. By a pipe G gaseous chlorine, produced in any
known manner or evolved from a holder of liquefied chlorine, passes either directly
by opening a cock or valve g to a siphon bend G¹ opening into the upper part of
the vessel A, or by closing the cock or valve g it has to pass through an inverted
siphon bend G2 and a valve box H communicating with a pump P which is charged
with water. As the plunger of the pump P moves up and down displacing the
water contained in its barrel and in the upright pipe P₁, the chlorine is drawn in by
the pipe G and discharged under pressure by the siphon bend G¹ into the vessel A.
The pump P may also be used as an air compressing pump, the supply of chlorine
being cut off by closing a cock or valve g', and.air being admitted to the suction of
the pump by opening a cock or valve g². This apparatus operates in the following
manner: The vessel A being charged with the almost liquid ore sludge, and the
manhole being tightly closed, the several cocks or valves are set, c b₁ glopen
and beg y², closed, and the pumps D and P are worked. Chlorine is thus forced
into the sludge which is kept circulating from the top of A down the pipe C to the
pumps D, and thence by the pipe B to the bottom of A. When the 'metal is
dissolved or mostly dissolved by the chlorine, as may be ascertained by testing a
sample drawn from either of the pipes B or C, the cocks or valves are shifted c bigg¹
and being closed and be opened. By the pumps D the sludge is now drawn from
the bottom of A and forced into the filter press F while by opening g' and working P
t

page_text: air may be forced by the pump P into A expelling the contents of A. It is some-
times necessary to maintain the circulation of the sludge while a portion of it is
passing to the filter press. In order to provide for this there may be several branches
as CC at different levels communicating with C with stopcocks or valves. By
opening one or other of these while the cocks or valves and e are partially
opened closed and c opened, circulation will go on while part of the contents of A
pass to the filter press F. The liquid forced out from the filter press F containing
the gold in solution is then treated in any known manner for eliminating the gold,
the spent liquor or the liquor itself before subsequent treatment being employed
wholly or in part for making up the sludge for a subsequent operation.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is
1. Apparatus for applying chlorine to the extraction of gold from ores, consisting
of a chlorinating vessel, a set of circulating pumps, and chlorine pump, a filter
press and the connecting pipes and valves, operating in combination substantially as
described.
2. For chlorinating ores containing gold, the combination of a chlorinating vessel
supplied with chlorine under pressure and ore sludge and a set of pumps effecting
circulation of the sludge in the vessel, substantially as described.
Unted He Lath do of Cletober XRO
Dated me Lath dox of Clotober 1X80
ABEL & IMRAY,
Agents for the Applicant.
ABEL & IMRAY,
Agents for the Applicant.