Improved Method of and Apparatus for Extracting Metals from their Ores, or other Compound Bodies containing them.
Year: 1897

page_text: Date of Application, 15th June, 1897-Accepted, 23rd Oct., 1897
COMPLETE SPECIFICATION.
Improved Method of and Apparatus for Extracting Metals from their
Ores, or other Compound Bodies containing them.
I, WILLIAM GEORGE MARSHALL FOOTE of 156 Vickery's Chambers 82 Pitt Street
Sydney in the Colony of New South Wales, 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 :-
1
This invention has for its object, an improvement in the method of and
apparatus for extracting metals from their ores or other compound bodies and
obtaining the said metals in a more or less pure state by liquation, and consists
essentially:-
First. f the peculiar construction of the retorts used for liquating. Second.
Of the construction of the furnace. Third. Of the fluxes used in the treatment.
In this improved method for extracting metals from their ores or other com-
pound bodies, the material to be treated is mixed with Lime, (CaO) either in an
anhydrous or Hydrated condition, and Carbon (C), or other such materials or
fluxes, as will under the influence of heat combine readily with the extraneous
matter associated or combined with the metal sought to be obtained. It is not
necessary that a fusable slag should be formed by the combination of the fluxes
used and the extraneous matter contained in the material under treatment. The
mixed material is then placed in closed retorts or other suitable vessels to the
exterior of which sufficient heat is applied to fuse the metal sought to be obtained,
the fluxes mixed with the materials as mentioned above combining with or retain-
ing the elements or compounds necessary to be removed from the metals sought
in order that the latter may be obtained in a liquid state.
The retorts used in this improved method are preferably constructed of fireclay,
but may be constructed of any other suitable material. The floor of these retorts is
raised in the centre so that there will be a fall from the raised centre to the sides.
A drain or channel runs longitudinally along the lower inner sides of the retorts,
so that the metals may flow along same towards a well provided at the
rear end of the retort, said well being placed below the retort floor level and into
this well the molten result of the material under treatment passes by gravitation,
and is kept in a molten state by the heat from the furnace. This well is provided
with a tap placed in such a position as will permit of the well being cleared or
drained off when required. In the outer wall of this well and above the tap a
small hole is made and a plug of any material or compound whose fusing point is
lower or equal to that of the metal sought to be obtained is inserted therein, this
for the purpose of ascertaining when the molten metal reaches the level of the
plug, when this happens the plug will fuse, and the attendant will then know it
is time to tap the well and draw off the molten results of the charge. The retorts
at each end are set in walls of the furnace (as shewn in Figure 2 of the drawings
herewith) in such a way that there is a slight fall towards the rear or well end,
two or more bars preferably of iron (may be water bars) run transversely across
the furnace and support the retorts.

page_text: 66
The ends of these bars project beyond the brick work on each side, and may be
used as
tie rods." The furnace is of a rectangular form and preferably constructed
of brick with an arched roof, in which an opening is left (somewhat in the position
shewn in Figure 2 of the drawings herewith) for a chimney provided with a
damper so as to regulate the draught and also the escape of the products of
combustion of the fuel used.
In order that this Invention may be more fully understood reference will now
be made to the accompanying sheets of drawings in which:-
Figure 1 is a transverse sectioilal elevation of the furnace and retorts.
Figure 2 is a longitudinal sectional elevation.
Figure 3 is a transverse sectional view of the retort.
Figure 4 is a longitudinal sectional view of the retort.
In all figures similar letters are uscu to denote similar parts.
A is the brick work of the furnace, with the arched roof B. The refractory
cheeks a and the inner sides b and the flue end or breast c, are preferably lined
with fire-brick.
+5
C is the fire box provided with a suitable door. D is the ash pit. E are the
retorts with the sloping floors F, and the drains or channels G. H is the well
provided at the rear end of the retort and extending downwards below the level
of the retort floor into which the molten results of the materials under treatment:
pass being conveyed there by gravitation along the drains or channels G. The
floor of this well is so constructed that it has an upward slope from the tap I to
the back. I is the tap placed in the outer side of the well H, in such a position
that the whole of the contents of the well may be cleared or drawn off. L is a
"try hole" pierced at any required height in the outer face of the well H, aud
into this try hole" is inserted a small plug of any material or compound
whose fusing point is less or equal to that of the metals sought to be obtained.
J is a partition placed near the rear end of the retort,' extending from the floor
upwards almost to the roof and is provided with openings or gates, at the points
where the drains or channels G meet the said partition. The object of this partition
being, to prevent any of the material under treatment falling into the well H. A
stay block K is placed in the position shewn in Figure 4 for the purpose of
strengthening and supporting the partition J. The rails or bars M are built into
the brick work A, and pass transversely across the furnace. These bars or rails
are used to assist in supporting the retorts E. The ends of these rails or bars M
extend outwards and beyond the sides of the furnace, and may be used in any
suitable manner as tie rods," or stays to assist in supporting or securing the side
walls of the furnace. Other "tie rods" or stays may be inserted or used to
support or strengthen the brick work of the furnace wherever necessary and in any
suitable manner. N is the chimney provided with a damper in any
suitable position let into the roof B of the furnace somewhat in the position as
shewn in Figure 2 and secured to the roof of the furnace by the L shaped
brackets ( or in any suitable manner. The openings P in the brick work A
are simply left to reduce the quantity of bricks required, and to make the con-
struction lighter, but are not in any way essential in the working of the apparatus.
The upper or charging ends of the retorts will be received and seated in a
suitable frame of iron or other suitable material provided in the brick work A.
The method of gauging the fluxes may be gathered from the following example,
which is arranged for the extraction of Antimony (atomic weight 120) from
its' ore -
**
:
r.
The proportion the various materials charged into the retorts, each to each,
would be in the exact ratio to their atomic equivalents, the Lime (CaO) specified,
is for the purpose of arresting or absorbing the Sulphur (S) contained in the
antimony ore, say as a sulphide (Sb.,S3), consequently to effect this separation, a
sulphur base, the combining equivalent of 32, of Antimony 120, the proportion of
Lime (CaO) must be in ratio to the percentage of metallic Antimony (Sb) con-
tained in the charge; the Carbon (C) specified, is used to act as a de-oxidising

page_text: agent, not only upon the free air enclosed within the retorts at the time of charg-
ing, but also upon any that may be freed during the process of Liquation. It is
impossible to fix the exact proportion of this element (C), but it may be taken as
sufficient to combine with the Oxygen (0) of the material, Lime (CaO), plus the
estimated volume enclosed in free air in exact ratio to the combining equivalents
of Carbon (C) and Oxygen (O). It may be found in actual work, that a larger
percentage of Lime (CaO) or Carbon (C), or both, is required to ensure the absorp-
tion of all the Sulphur (S) and Oxygen (0) contained or set free in the retort
during the operation of Liquation.
It is always preferable that the ore being treated should be broken and graded
so that a fairly correct estimation may be obtained of the quantity of Lime (CaO)
and Carbon (C) required to successfully treat the charge.
Having now particularly described and ascertained the nature of this
invention and in what manner the same is to be performed I declare that what
I claim is:
1. The improved method of extracting metals from their ores or other compound
bodies, the mixing of Lime (Ca) either in an anhydrous or Hydrated condition, and
Carbon (C) either together or separately, with the materials under treatment
according to the requirements of the said material for the purpose of combining
with or retaining the elements or compounds necessary to be removed from the
metals sought to be obtained. The mixed materials being placed in retorts such
as E, and subjected to the influence of heat substantially as herein described
explained and for the purposes set forth.
2. In apparatus for extracting metals from their ores or other compound bodies,
a retort or retorts, such as E, in combination with a furnace structure such
as A, B, D, C, and N, and bars or rods, such as M, substantially as herein described
explained and illustrated in the drawings.
3. In apparatus for extracting metals from their ores or other compound bodies,
a retort or retorts, such as E in combination with the furnace having reverberatory
cheeks such as a. A reverberatory flue end or breast such as c, under a reverber-
atory roof such as b, and a chimney such as N, substantially as herein described
and illustrated in the drawings.
4. In closed retorts for the extraction of metals from their ores or other com-
pound bodies, a sloping floor such as F, drains or channels such as G, substantially
as herein described and illustrated in the drawings.
5. In closed retorts for extracting metals from their ores or other compound
bodies, a sloping floor such as F, drains or channels such as G, a partition such
as J, a stop block such as K a well such as H, with a tap hole such as I, and a
try hole" such as L, substantially as herein described and illustrated in the
drawings.
66
6. The combination and arrangement of the various parts herein described,
explained and illustrated all together forming the improved apparatus for the
extraction of metals from their ores or other compound bodies containing them.
Dated this 14th day of June 1897.
CHEESBROUGH & ROYSTON,
15 Water Street, Liverpool, Applicant's Patent Agents.