A Process for Extracting Precious Metals from Refractory Ores.
Year: 1896

page_text: Date of Application, 3rd June, 1896
Complete Specification Left, 4th Aug., 1896-Accepted, 5th Sept., 1896
PROVISIONAL SPECIFICATION.
A Process for Extracting Precious Metals from Refractory Ores.
I, JAMES WOOLFORD, of No. 659 Commercial Road East, in the County of
Loudon, Metallurgist, do hereby declare the nature of this invention to be as
follows:--
My invention relates to the extraction of precious metals from refractory ores
which may be in their natural state or in the condition of clinkers after calcination
or other treatment.
For this purpose, I crush the ore, and to 2 parts of it by weight I add 2 parts of
antimony trioxide, 1 part of the residue from reduction of antimony oxide, and
1 part of finely pulverised coal or charcoal.
These substances thoroughly mixed are fused in any suitable furnace, the
antimony oxide becoming reduced and the antimony forming an alloy with the
precious metal. This alloy is tapped off and treated in a furnace the bed of which
is glazed with a mixture of borax and sulphate of soda. The antimony becomes
oxidised, the oxide passing away as fumes which can be collected and treated in
any known way. The precious metal remains on the furnace bed where it receives
additions from fresh batches of the alloy, until enough has accumulated for
removal.
Dated this 3rd day of June 1896.
ABEL & IMKAY,
Agents for the Applicant.
A Process for Extracting Precious Metals from Refractory Ores.
I, JAMES WOOLFORD, of No. 659 Commercial Road East, in the County of
London, Metallurgist, 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 the extraction of precious metals from refractory ores
by treating with antimony oxides, and to the recovery of the antimony employed
in this treatment.
The ore whether in its natural state or in the state of clinkers after roasting or
other treatment is crushed and thoroughly mixed with an equal weight of antimony
trioxide, with half its weight of the residue from reduction of antimony oxide,
and with half its weight of finely pulverised coal or charcoal. The mixture being
fused in a cupola or other suitable furnace, the antimony oxide is reduced and the
antimony forms an alloy with the precious metal.
This alloy is tapped off and treated in an oxidising furnace the bed of which
is glazed with a mixture of borax and sulphate of soda.
In this furnace the antimony becomes oxidised, the oxide passing away as fumes
while the precious inetal remains on the bed of the furnace.
Successive batches of the alloy may be treated until there is accumulation of the
precious metal sufficient for being run off.
D

page_text: The combustion gases with the fumes of antimony oxide may be drawn by a fan
through cooling passages and depositing chambers in which a large proportion of
the oxide is deposited. In order to recover the last portions of the oxide and clear
the gases from it, 1 employ in conjunction with the fan, which creates the draught
through the cooling passages and depositing chambers, a nozzle furnishing a water
spray which mingles with the gases and fumes and is effectually mixed up with
them by the blades of the fan. The water with the oxide suspended in it is drawn
away from the lower part of the fan while the gases pass away to a chimney or
elsewhere almost entirely free from fumes.
Fig. 1 of the accompanying drawings is an elevation partly in section and Fig. 2
is a transverse section of the fan and water nozzle, A is the conduit leading the
fumes from the depositing chambers and cooling passages to the suction fan B.
In the passage A is arranged a distributing nozzle E by which water is sent, in
spray, to mingle with the fumes as they enter the fan, the blades of which break
up the water and dash it about along with the fumes causing separation of the
particles suspended in them.
While the gases thus cleared of the suspended particles pass away by the
conduit C to a chimney or other discharge, the water mixed with the solid particles
collects in the lower part of the fan and flows out to depositing tanks D in which
the solid material is collected. Instead of sending water alone by the nozzle E,
water mingled with steam may be sent into the conduit, the steam being used as an
injector jet to cause the water to leave the nozzle with great speed and in a greatly
subdivided condition.
The oxide collected in the cooling passages and deposit chambers as well as
that removed from the depositing tanks D and dried may be used to treat fresh
batches of ore, or may be reduced in any known way so as to obtain metallic
antimony.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The herein described process for extracting precious metals from refractory ores
by fusing the crushed ore intimately mixed with antimony oxides and pulverised
fuel, thus producing an alloy of antimony with the precious metals, treating the
alloy in a suitable furnace thereby oxidising the antimony the oxide of which being
driven off as fumes leaves the precious metals on the furnace bed and may be
recovered for subsequent use by causing the combustion gases and fumes to pass
from the oxidising furnace through cooling passages and depositing chambers by
means of a fan, wherein the gases and residuary fumes are mixed with water and
whence the gases pass away while the oxide suspended in water is drawn off to
depositing chambers.
Dated this 4th dow of August 1806
ABEL & IMRAY,
Agents for the Applicant.