Improved Method and Apparatus for Treating Refractory Ores containing Gold, Silver, Nickel, and the like.
Year: 1897

page_text: Date of Application, 8th Mar., 1897
Complete Specification Left, 8th Dec., 1897-Accepted, 8th Jan.,
1898.
PROVISIONAL SPECIFICATION.
Improved Method and Apparatus for Treating Refractory Ores
containing Gold, Silver, Nickel, and the like.
JOHN EDWARD PRESTON, 8 Burton Road, Brixton, London, S.W., Engineer, do
hereby declare the nature of this invention to be as follows:-
-
This Invention consists of a specially constructed Furnace to which the ore
is fed or conveyed in a finely pulverized condition by an air current which may be
used for the blast for raising the temperature.
This Furnace is constructed in a circular or other suitable shape and may be
tapered slightly to the top and may be built of fire bricks or an outer casing of
iron lined with fire bricks or other suitable fire resisting material, the bottom is
provided with an opening in the centre, over which is fixed a conical chamber
made of suitable fire resisting material perforated with holes inclined upwards
and a larger hole at the top, the fire space being between the outer surface of the
inside cone and the inner surface of the Furnace.
At a proper distance above the top of the conical chamber I place a large
circular plate or block of fire clay or other suitable substance so shaped as to retain
and partially deflect the heat leaving only a small annular space between the outer
edge of the fire clay plate or block and the inner surface of the Furnace.
In feeding the pulverized ore to this Furnace I fix the air pipe to the bottom of
the internal cone this air blast carrying the ore and inducing a draught through
the holes in the conical chamber causing the heat to ascend and incandesce the fire
clay plate or block at the top of the Furnace.
The pulverized ore being subjected to increasing heat until it reaches the fire
clay plate or block when it is reduced and deflected, the heavier metal remaining
in the furnace and the more volatile motals being carried over the fire clay plate
or block and caught by means of a water bath, water curtain or other suitable
means.
When constructing larger furnaces I may use some auxiliary air blast or blasts
placed at suitable intervals in or through the outside of Furnace.
Dated thie 8th day of March 1897
Improved Method and Apparatus for Treating Refractory Ores.
containing Gold, Silver, Nickel, and the like.
I, JOIN EDWARD PRESTON, of 8 Burton Road, Brixton, in the County of London,
W., Engineer, do hereby declare the nature of this invention and in what manner
Price &1.1

page_text: the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
My invention relates to a specially constructed furnace or apparatus for the treat-
ment of refractory ores, for the purpose of extracting or separating therefrom,
such precious or other metal or metals as they may contain, the object of my said
invention being to provide an apparatus and system that may attain the ends
stated more rapidly, effectively, and at less cost than has been possible by the
methods and means hitherto employed for the same purpose.
My invention consists of a suitably shaped furnace built of fire bricks or other
fire resisting material, or an outer casing of iron lined with fire bricks or other 1
suitable material, and so constructed and arranged that the base or bottom is
provided with a central opening surrounded by a fixed or integral conical perforated
chamber, extending upwardly, into the said furnace, the finely pulverized ore being
fed by the force of a blast from a suitable blower, through conduits terminating
in a nozzle fixed within the said chamber, from which the said pulverized ore is 1
caused to exude with great force out of the top of the said chamber, and to impinge
against the under surface of a block or diaphragm of fire clay or other suitable
substance, fixed in such a position, within the furnace as to become incandescent
by the heat, and by impinging against this, the said pulverized ore would become
atomized, and the metallic portions be deflected thereby, in a downward direction 2
into the body of the furnace, suitable exhausts being provided through which the
recovered metal may be led or drained from the furnace, while the fumes and
dust would be conveyed by convection in an upward direction through suitable
apertures in the said diaphragms into the atmosphere, or caused to traverse a con-
duit leading past a waler curtain or and into a suitable condenser, when such 2
fumes or dust may be impregnated with such volatile metallic particles as may
be worthy of recovery.
In order that my improved system and apparatus and the manner, or sub-
stantially so, in which I purpose constructing the latter, may be fully understood,
reference is hereinafter made to the accompanying drawings, in which the furnace 3
and certain of its conduits are shewn in section.
In carrying my invention into effect, I prefer to construct the furnace proper A
of circular formation in plan, and slightly coned or tapered from the bottom to
the top, and I may provide the said furnace wholly of fire bricks or other suitable
material or with an outer casing of iron lined with fire bricks or other material but 3
preferably the former, and in any convenient part of the said furnace I may pro-
vide an opening and door, or openings and doors (not shown) through which the fuel
may be fed, when solid fuel is used, but when petroleum or other liquid fuel is
employed this may be fed into the furnace by other means hereinafter explained.
By preference the said furnace would rest upon any number of suitable blocks B, 4
and between and within these the bottom of A would be provided with a central
aperture C, surrounded by a conical or tapered chamber 1), standing up within the
furnace, and provided with any number of perforations or holes E, inclined in an
upward direction from the outer to the inner surface. The said chamber may
conveniently be of the same material as A, when the latter is constructed without 4
a metallic casing, and may be either fixed in position by any suitable means, or
formed integrally with A, preferably the latter as shewn. The upper end of a
furnace is closed by a fire clay or other diaphragm F, having a central opening G,
and upon the said diaphragm rests the funnel shaped mouth of a fume and dust
conduit or exhaust H, which may bend and extend in any direction, its final end H¹, 5
leading to a suitable condenser, (not shewn) and in a direct line above the open-
ing G in the said conduit H is provided with a branch H³, leading to the
atmosphere, in which a suitable damper J. is provided, by means of which the said
branch may be opened or closed at will.
In any suitable position adjacent to the furnace and convenient for operation 5
by any available power, I provide a suitable blower K, the air current from which

page_text: is conveyed by a pipe L to surround or partly surround the furnace A, and at
suitable intervals in this I provide any number of depending branches M, each con-
nected to a suitable fire clay or other nozzle or tuyere N, leading through
apertures in the wall of A into the fire space O, and by means of the said conduit
and nozzles the whole or part of the said blast may be employed, when needed,
for imparting extra draught to the furnace, suitable throttle or other valves being
provided in any part of the conduit L, when necessary, for opening and closing
this at will. The conduit L is provided with a branch pipe P, which terminates in a
nozzle R within the chamber D, and at any convenient part of the said branch
pipe P, a suitable adjustable hopper T is provided, which receives the finely
pulverized ore to be treated, and anywhere between the said hopper and the con-
duit L, the said pipe P is provided with a screw down or other suitable valve such
as S, by means of which the passage through P may be wholly or partly closed,
or opened at will, to regulate the force of the blast. The manner of operation
is as follows:
Given that the fire in the furnace has been lighted, and in a condition for work,
the air blast through L may be wholly or partly closed, when the ore, in a finely
pulverized condition, would be fed into the hopper T, and the valve S be opened,
when the current of air passing through 1', would convey with it the pulverized
ore, which would be thereby forced up through the nozzle R, and out at the top
of the chamber D, and this forced draught through D would create an updraught
of superheated air through the perforations E in D, thus superheating the powdered
ore, which would be caused to impinge upon the point a of the under surface of
a coned plate or diaphragm V, suspended beneath the diaphragm F, and now white
hot or incandescent from the heat of the furnace, and this being now the hottest
part of the furnace, such impact with V would vaporize or atomize the pulverized
ore, and deflect this in all directions from the centre of the furnace, when the
metallic portions would be melted and fall into the fire at O, and pass out through
suitable outlets b, while the fumes, dust, and more volatile portions would, by the
aid of convection, (and may be by assisted draught through the nozzles N,) pass
upwardly through apertures c in V, and through the opening G in F into the
conduit H, and by opening the damper J be allowed to pass out through H2 into
the atmosphere, or by closing the said damper to pass along the conduit H and H¹
into a suitable condenser, according to the constituents of the fumes, or as the ore
under treatment is known to contain metal of greater or lesser density, and for
the purpose of recovering from the said fumes such metallic portions as may be
valuable, I may, in lieu of, or in addition to the use of a condenser in the usual way,
provivide a water curtain at the end of the conduit H, (shewn by dotted lines at e)
by the means of a water conduit & having suitable perforations through which the
water may fall.
I may find it convenient to employ petroleum or other liquid fuel in lieu of
ordinary fuel, in which case I may employ means by which such liquid fuel may be
conveyed into the furnace O, by the use of certain of the nozzles or tuyeres N,
which, for this purpose, may be perforated at their final ends, so as to emit the said
liquid fuel in the form of a spray, suitable valves or taps being provided, where
necessary, to regulate the flow of the said liquid fuel.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is:-
1st. The improved method of and apparatus for treating refractory ores, sub-
stantially as herein described and shewn.
2nd. In the treatment of refractory ores, the combination of a reducing furnace,
and means for conveying the said ores in a finely powdered condition thereinto
by the use of a powerful air blast, substantially as herein described and shewn.
3rd. In the treatment of refractory ores, the combination of a furnace A, having
diaphragms F and V, and chamber D, with perforations E, with means for convey-

page_text: ing a blast of air to the said furnace from a suitable blower, and by the means of a
conduit such as P, and nozzle R, for utilizing the said blast for conveying finely
pulverized ore from a hopper such as T to the said furnace, and means such as a
conduit H H and H³ and water curtain e for exhausting the fumes from the
furnace, and recovering volatile metallic particles therefrom, substantially as 5
herein set forth and shewn.