Improvements in and connected with Furnaces for Treating Ores containing Precious Metals and other Ores.
Year: 1897

page_text: Improvements in and connected with Furnaces for Treating Ores
containing Precious Metals and other Ores.
I, STEPHEN ALLEY, of the Sentinel Works, Polmadie Road, in the County of
Glasgow, North Britain, Engineer,
My said invention has for its object to provide improved furnace apparatus and
arrangements for treating ores, especially such as contain precious metals, with
gases. The gas or mixture of gases preferably employed in carrying out my
invention is what is known as water gas, but other gases may also be used in my
improved apparatus; or the furnace may be used for roasting ores without using
gas.
My improved apparatus comprises an oven of a circular form in plan, and the
bottom of which is of an annular dish-like construction. The oven is provided
with a cover of a curved form and having a downwardly projecting cylindrical
edge which dips into a trough formed round the edge of the oven bottom, and
filled with sand. The cover is provided with a valved opening for feeding in ore,
and with an outlet passage for gas. Fixed on a central vertical shaft there is,
within the oven an armed head to which are fixed by their shanks ploughs or
stirrers which on the shaft rotating turn over and stir the ores. The armed head
and shaft are supported by an annular series of castiron balls rolling round an
annular gutter formed at the upper part of a vertical flange encircling a central
opening in the oven bottom. The shaft is tubular the gas to act on the ores being
introduced up through it, and the armed head and the ploughs are made hollow
and so that the gas issues from the ploughs amongst the ores.
The shaft has
fixed to it just below the oven bottom, an outer cylindrical casting which dips into
an annular cup filled with sand. The gas reaches the tubular shaft by a fixed
vertical pipe which projects up into the shaft, and the communication is sealed
by water in an annular casing into which the lower end of the casting dips.
It is necessary to prevent air or other gas from entering the oven and mixing
with the water gas or other gas therein; and for this purpose the gas applied in
the oven is forced in by a pump or blower or the gas may be generated with some
pressure so as to maintain a pressure above that of the atmosphere, the gas outlet
being contracted or being provided with a suitably loaded valve to prevent lessening
of the internal pressure.
The rotating ploughs are shaped so as when moving in one direction to stir the
ores equally outwards and inwards and so as when moving in the other direction
to move the ores outwards and towards a discharge outlet. The armed head is
also provided with one or more adjustable deflecting blades to move the ores
inwards when tending to accumulate towards the outer part of the oven.
The oven is heated by means of flues under its bottom, and either by ordinary
fire gases or by ignited combustible gas.
An oven of the improved construction may be used for dealing with separate
charges of ores; or a continuous aotion may be obtained by combining a number

page_text: of the ovens in a descending series, the ore fed in at the highest of the series being
transferred through closed ducts from each oven to the next lower one.
In some cases provision is made for passing steam through the oven to expel
the gas before discharging ore that has been treated with gas.
Dated this Twenty fourth day of June 1897.
EDMUND HUNT,
Applicant's Agent.
Improvements in and connected with Furnaces for Treating Ores
containing Precious Metals and other Ores.
I, STEPPEN ALLEY, of the Sentinel Works, Polmadie Road, in the County of
Glasgow, North Britain, 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, that is to say:
My said invention has for its object to provide improved furnace apparatus and
arrangements: for treating ores, especially such as contain precious metals, with
gases. The
e gas or mixture of gases preferably employed in carrying out my
invention is what is known as water gas but other gases may also be used in my
improved apparatus; or the furnace may be used for roasting ores without using
gas.
are
My improved apparatus comprises an oven made with inlets and outlets for the
ores, and for the gas, and has turning centrally within it on a vertical tubular
shaft a hollow armed head to which ploughs or stirrers and deflecting blades an
fixed. The gas is forced or enters under pressure through the tubular vertical shaft
into the hollow armed head, from which it issues by passages formed in, the
ploughs or stirrers into the oven among the ores. The oven is heated by means
of flues under its bottom by ordinary fire gases or by ignited combustible gas.
Ovens of the kind described may be used separately or a continuous action may
be obtained by combining a number of ovens.:
And in order that my said invention and the manner of performing the same
inay be properly understood I hereunto append two sheets of explanatory drawings
to be hereinafter referred to and showing apparatus as made according to my
invention.
17 P
Figure, 1, on Sheet, 1, of the drawings is a vertical section of one modification
of the apparatus. Figures, 2, and 3, on Sheet, 2, are respectively a sectional eleva-
tion and a horizontal section of the same modification drawn to a smaller scale
and having some parts omitted for convenience. Figure, 4, is a sectional elevation
of a second modification of the apparatus. Figures, 5, and 6; are respectively a
sectional, elevation and a horizontal section of a detail. Figure, 7, is a vertical
section of a third modification of the apparatus. In these drawings the same
reference letters, are used to mark the same or like parts wherever they are
repeated.
My improved apparatus comprises an oven, A, of a circular form in plan, and
the bottom of which is of an annular dish-like construction. The oven, A, is
provided with a cover,. B, of a curved form, and having a downwardly projecting
cylindrical edge which dips into a trough, C, formed round the edge of, the oven
bottom and filled by preference with sand or other suitable material. The
cover, B, is provided with a valved opening, D, for feeding in ore, and with an
outlet passage, E, for gas. Fixed on a central vertical shaft, G, there is, within
the oven, A, an armed head, H, to which are fixed by their shanks, ploughs or

page_text: stirrers, J, which on the shaft rotating turn over and stir the ores. The shaft, G,
is driven through bevil wheels, G 1, by any well-known means. The armed head, H,
and shaft, (i, are supported by an annular series of castiron balls, K, rolling round
an annular gutter, L, formed at the upper part of a vertical flange, M, encircling
a central opening in the oven bottom. The shaft, G, is tubular the gas to act on the
ores being introduced up through it, and the armed head, H, and the ploughs, J,
are made hollow, and so that the gas issues from the ploughs amongst the ores.
The shaft, G, has fixed to it at about the level of the oven bottom, an outer
cylindrical casting, N, which dips into an annular cup, P, filled with sand or other
suitable material. The gas reaches the tubular shaft, G, by a fixed vertical pipe, Q,
which projects up into the shaft, and the communication is sealed by water in an
annular casing, R, into which the lower end of the shaft dips.
It is necessary to prevent air or other gas from entering the oven, A, and mixing
with the water gas or other gas therein; and for this purpose the gas applied in
the oven, A, is forced in by a pump or blower (not shown) or the gas may be
generated with some pressure so as to maintain a pressure above that of the
atmosphere, the gas outlet, E, being contracted or being provided with a suitably
loaded valve to prevent lessening of the internal pressure.
The rotating ploughs, J, are shaped so as when moving in one direction to stir
the ores equally outwards and inwards and so as when moving in the other
direction to move the ores outwards and towards a discharge outlet, S. The
armed head, H, is also provided with one or more adjustable deflecting blade,
to move the ores inwards when tending to accumulate towards the outer part of
the oven.
The oven,
A, is heated by means of flues, V, under its bottom and either by
ordinary fire gases or by ignited combustible gas.
An oven of the improved construction may be used for dealing with separate
charges of ores; or a continuous action may be obtained by combining a number
of the ovens, A, in a descending series, the ore fed in at the highest of the serios
being transferred through closed ducts, W, from each oven to the next lower one
as in the modification shown in Figure, 4.
In the modification shown in Figure, 7, to protect the iron work from fumes,
the oven, A, and cover, B, are lined with or composed of brickwork, the cover being
of curved form and having an outer metal flanged casing, X, on which it rests on
the top of the oven, A. The armed head, H, is covered with a coating of material
that is acid proof and is along with the shaft, G, supported by an annular series
of cast iron balls, K, rolling round a gutter, L, formed in a casing, Y, fixed to the
oven bottom, the shaft being fitted with a cone bearing piece, Z.
The other parts of this modification not referred to are to be understood to be
the same as or similar to the corresponding parts of the modification herein before
described.
In some cases provision is made for passing steam through the oven to expel
the gas before discharging ore that has been heated with gas.
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. An improved furnace for treating ores containing precious metals, and other
ores, comprising an externally heated oven having centrally within it a rotating
tubular shaft fast on which is a hollow armed head with ploughs or stirrers and
deflecting blades gas (preferably water gas) being forced or entering under pressure
into the oven amongst the ores through the vertical tubular shaft, hollow armed
head and ploughs, substantially as herein before described and as shown in the
accompanying drawings.
2. An improved furnace for treating ores containing precious metals, and other
ores, comprising an externally heated oven having centrally within it a vertical
$17

page_text: rotating tubular shaft fast on which is a hollow armed head with ploughs or
stirrers and deflecting blades substantially as hereinbefore described.
3. The treating of heated ores with water gas or other gas in apparatus sub-
stantially such as is hereinbefore described.
Dated this Thanty third day of March 1898.
EDMUND HUNT,
Applicant's Agent.